1 //===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This file implements semantic analysis for declarations.
11 //===----------------------------------------------------------------------===//
13 #include "TypeLocBuilder.h"
14 #include "clang/AST/ASTConsumer.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/ASTLambda.h"
17 #include "clang/AST/CXXInheritance.h"
18 #include "clang/AST/CharUnits.h"
19 #include "clang/AST/CommentDiagnostic.h"
20 #include "clang/AST/DeclCXX.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/AST/DeclTemplate.h"
23 #include "clang/AST/EvaluatedExprVisitor.h"
24 #include "clang/AST/ExprCXX.h"
25 #include "clang/AST/NonTrivialTypeVisitor.h"
26 #include "clang/AST/StmtCXX.h"
27 #include "clang/Basic/Builtins.h"
28 #include "clang/Basic/PartialDiagnostic.h"
29 #include "clang/Basic/SourceManager.h"
30 #include "clang/Basic/TargetInfo.h"
31 #include "clang/Lex/HeaderSearch.h" // TODO: Sema shouldn't depend on Lex
32 #include "clang/Lex/Lexer.h" // TODO: Extract static functions to fix layering.
33 #include "clang/Lex/ModuleLoader.h" // TODO: Sema shouldn't depend on Lex
34 #include "clang/Lex/Preprocessor.h" // Included for isCodeCompletionEnabled()
35 #include "clang/Sema/CXXFieldCollector.h"
36 #include "clang/Sema/DeclSpec.h"
37 #include "clang/Sema/DelayedDiagnostic.h"
38 #include "clang/Sema/Initialization.h"
39 #include "clang/Sema/Lookup.h"
40 #include "clang/Sema/ParsedTemplate.h"
41 #include "clang/Sema/Scope.h"
42 #include "clang/Sema/ScopeInfo.h"
43 #include "clang/Sema/SemaInternal.h"
44 #include "clang/Sema/Template.h"
45 #include "llvm/ADT/SmallString.h"
46 #include "llvm/ADT/Triple.h"
51 using namespace clang;
54 Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType) {
56 Decl *Group[2] = { OwnedType, Ptr };
57 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, 2));
60 return DeclGroupPtrTy::make(DeclGroupRef(Ptr));
65 class TypeNameValidatorCCC final : public CorrectionCandidateCallback {
67 TypeNameValidatorCCC(bool AllowInvalid, bool WantClass = false,
68 bool AllowTemplates = false,
69 bool AllowNonTemplates = true)
70 : AllowInvalidDecl(AllowInvalid), WantClassName(WantClass),
71 AllowTemplates(AllowTemplates), AllowNonTemplates(AllowNonTemplates) {
72 WantExpressionKeywords = false;
73 WantCXXNamedCasts = false;
74 WantRemainingKeywords = false;
77 bool ValidateCandidate(const TypoCorrection &candidate) override {
78 if (NamedDecl *ND = candidate.getCorrectionDecl()) {
79 if (!AllowInvalidDecl && ND->isInvalidDecl())
82 if (getAsTypeTemplateDecl(ND))
83 return AllowTemplates;
85 bool IsType = isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND);
89 if (AllowNonTemplates)
92 // An injected-class-name of a class template (specialization) is valid
93 // as a template or as a non-template.
95 auto *RD = dyn_cast<CXXRecordDecl>(ND);
96 if (!RD || !RD->isInjectedClassName())
98 RD = cast<CXXRecordDecl>(RD->getDeclContext());
99 return RD->getDescribedClassTemplate() ||
100 isa<ClassTemplateSpecializationDecl>(RD);
106 return !WantClassName && candidate.isKeyword();
109 std::unique_ptr<CorrectionCandidateCallback> clone() override {
110 return llvm::make_unique<TypeNameValidatorCCC>(*this);
114 bool AllowInvalidDecl;
117 bool AllowNonTemplates;
120 } // end anonymous namespace
122 /// Determine whether the token kind starts a simple-type-specifier.
123 bool Sema::isSimpleTypeSpecifier(tok::TokenKind Kind) const {
125 // FIXME: Take into account the current language when deciding whether a
126 // token kind is a valid type specifier
129 case tok::kw___int64:
130 case tok::kw___int128:
132 case tok::kw_unsigned:
139 case tok::kw__Float16:
140 case tok::kw___float128:
141 case tok::kw_wchar_t:
143 case tok::kw___underlying_type:
144 case tok::kw___auto_type:
147 case tok::annot_typename:
148 case tok::kw_char16_t:
149 case tok::kw_char32_t:
151 case tok::annot_decltype:
152 case tok::kw_decltype:
153 return getLangOpts().CPlusPlus;
155 case tok::kw_char8_t:
156 return getLangOpts().Char8;
166 enum class UnqualifiedTypeNameLookupResult {
171 } // end anonymous namespace
173 /// Tries to perform unqualified lookup of the type decls in bases for
175 /// \return \a NotFound if no any decls is found, \a FoundNotType if found not a
176 /// type decl, \a FoundType if only type decls are found.
177 static UnqualifiedTypeNameLookupResult
178 lookupUnqualifiedTypeNameInBase(Sema &S, const IdentifierInfo &II,
179 SourceLocation NameLoc,
180 const CXXRecordDecl *RD) {
181 if (!RD->hasDefinition())
182 return UnqualifiedTypeNameLookupResult::NotFound;
183 // Look for type decls in base classes.
184 UnqualifiedTypeNameLookupResult FoundTypeDecl =
185 UnqualifiedTypeNameLookupResult::NotFound;
186 for (const auto &Base : RD->bases()) {
187 const CXXRecordDecl *BaseRD = nullptr;
188 if (auto *BaseTT = Base.getType()->getAs<TagType>())
189 BaseRD = BaseTT->getAsCXXRecordDecl();
190 else if (auto *TST = Base.getType()->getAs<TemplateSpecializationType>()) {
191 // Look for type decls in dependent base classes that have known primary
193 if (!TST || !TST->isDependentType())
195 auto *TD = TST->getTemplateName().getAsTemplateDecl();
198 if (auto *BasePrimaryTemplate =
199 dyn_cast_or_null<CXXRecordDecl>(TD->getTemplatedDecl())) {
200 if (BasePrimaryTemplate->getCanonicalDecl() != RD->getCanonicalDecl())
201 BaseRD = BasePrimaryTemplate;
202 else if (auto *CTD = dyn_cast<ClassTemplateDecl>(TD)) {
203 if (const ClassTemplatePartialSpecializationDecl *PS =
204 CTD->findPartialSpecialization(Base.getType()))
205 if (PS->getCanonicalDecl() != RD->getCanonicalDecl())
211 for (NamedDecl *ND : BaseRD->lookup(&II)) {
212 if (!isa<TypeDecl>(ND))
213 return UnqualifiedTypeNameLookupResult::FoundNonType;
214 FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
216 if (FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound) {
217 switch (lookupUnqualifiedTypeNameInBase(S, II, NameLoc, BaseRD)) {
218 case UnqualifiedTypeNameLookupResult::FoundNonType:
219 return UnqualifiedTypeNameLookupResult::FoundNonType;
220 case UnqualifiedTypeNameLookupResult::FoundType:
221 FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
223 case UnqualifiedTypeNameLookupResult::NotFound:
230 return FoundTypeDecl;
233 static ParsedType recoverFromTypeInKnownDependentBase(Sema &S,
234 const IdentifierInfo &II,
235 SourceLocation NameLoc) {
236 // Lookup in the parent class template context, if any.
237 const CXXRecordDecl *RD = nullptr;
238 UnqualifiedTypeNameLookupResult FoundTypeDecl =
239 UnqualifiedTypeNameLookupResult::NotFound;
240 for (DeclContext *DC = S.CurContext;
241 DC && FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound;
242 DC = DC->getParent()) {
243 // Look for type decls in dependent base classes that have known primary
245 RD = dyn_cast<CXXRecordDecl>(DC);
246 if (RD && RD->getDescribedClassTemplate())
247 FoundTypeDecl = lookupUnqualifiedTypeNameInBase(S, II, NameLoc, RD);
249 if (FoundTypeDecl != UnqualifiedTypeNameLookupResult::FoundType)
252 // We found some types in dependent base classes. Recover as if the user
253 // wrote 'typename MyClass::II' instead of 'II'. We'll fully resolve the
254 // lookup during template instantiation.
255 S.Diag(NameLoc, diag::ext_found_via_dependent_bases_lookup) << &II;
257 ASTContext &Context = S.Context;
258 auto *NNS = NestedNameSpecifier::Create(Context, nullptr, false,
259 cast<Type>(Context.getRecordType(RD)));
260 QualType T = Context.getDependentNameType(ETK_Typename, NNS, &II);
263 SS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
265 TypeLocBuilder Builder;
266 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
267 DepTL.setNameLoc(NameLoc);
268 DepTL.setElaboratedKeywordLoc(SourceLocation());
269 DepTL.setQualifierLoc(SS.getWithLocInContext(Context));
270 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
273 /// If the identifier refers to a type name within this scope,
274 /// return the declaration of that type.
276 /// This routine performs ordinary name lookup of the identifier II
277 /// within the given scope, with optional C++ scope specifier SS, to
278 /// determine whether the name refers to a type. If so, returns an
279 /// opaque pointer (actually a QualType) corresponding to that
280 /// type. Otherwise, returns NULL.
281 ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
282 Scope *S, CXXScopeSpec *SS,
283 bool isClassName, bool HasTrailingDot,
284 ParsedType ObjectTypePtr,
285 bool IsCtorOrDtorName,
286 bool WantNontrivialTypeSourceInfo,
287 bool IsClassTemplateDeductionContext,
288 IdentifierInfo **CorrectedII) {
289 // FIXME: Consider allowing this outside C++1z mode as an extension.
290 bool AllowDeducedTemplate = IsClassTemplateDeductionContext &&
291 getLangOpts().CPlusPlus17 && !IsCtorOrDtorName &&
292 !isClassName && !HasTrailingDot;
294 // Determine where we will perform name lookup.
295 DeclContext *LookupCtx = nullptr;
297 QualType ObjectType = ObjectTypePtr.get();
298 if (ObjectType->isRecordType())
299 LookupCtx = computeDeclContext(ObjectType);
300 } else if (SS && SS->isNotEmpty()) {
301 LookupCtx = computeDeclContext(*SS, false);
304 if (isDependentScopeSpecifier(*SS)) {
306 // A qualified-id that refers to a type and in which the
307 // nested-name-specifier depends on a template-parameter (14.6.2)
308 // shall be prefixed by the keyword typename to indicate that the
309 // qualified-id denotes a type, forming an
310 // elaborated-type-specifier (7.1.5.3).
312 // We therefore do not perform any name lookup if the result would
313 // refer to a member of an unknown specialization.
314 if (!isClassName && !IsCtorOrDtorName)
317 // We know from the grammar that this name refers to a type,
318 // so build a dependent node to describe the type.
319 if (WantNontrivialTypeSourceInfo)
320 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get();
322 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context);
323 QualType T = CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc,
325 return ParsedType::make(T);
331 if (!LookupCtx->isDependentContext() &&
332 RequireCompleteDeclContext(*SS, LookupCtx))
336 // FIXME: LookupNestedNameSpecifierName isn't the right kind of
337 // lookup for class-names.
338 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName :
340 LookupResult Result(*this, &II, NameLoc, Kind);
342 // Perform "qualified" name lookup into the declaration context we
343 // computed, which is either the type of the base of a member access
344 // expression or the declaration context associated with a prior
345 // nested-name-specifier.
346 LookupQualifiedName(Result, LookupCtx);
348 if (ObjectTypePtr && Result.empty()) {
349 // C++ [basic.lookup.classref]p3:
350 // If the unqualified-id is ~type-name, the type-name is looked up
351 // in the context of the entire postfix-expression. If the type T of
352 // the object expression is of a class type C, the type-name is also
353 // looked up in the scope of class C. At least one of the lookups shall
354 // find a name that refers to (possibly cv-qualified) T.
355 LookupName(Result, S);
358 // Perform unqualified name lookup.
359 LookupName(Result, S);
361 // For unqualified lookup in a class template in MSVC mode, look into
362 // dependent base classes where the primary class template is known.
363 if (Result.empty() && getLangOpts().MSVCCompat && (!SS || SS->isEmpty())) {
364 if (ParsedType TypeInBase =
365 recoverFromTypeInKnownDependentBase(*this, II, NameLoc))
370 NamedDecl *IIDecl = nullptr;
371 switch (Result.getResultKind()) {
372 case LookupResult::NotFound:
373 case LookupResult::NotFoundInCurrentInstantiation:
375 TypeNameValidatorCCC CCC(/*AllowInvalid=*/true, isClassName,
376 AllowDeducedTemplate);
377 TypoCorrection Correction = CorrectTypo(Result.getLookupNameInfo(), Kind,
378 S, SS, CCC, CTK_ErrorRecovery);
379 IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo();
381 bool MemberOfUnknownSpecialization;
382 UnqualifiedId TemplateName;
383 TemplateName.setIdentifier(NewII, NameLoc);
384 NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier();
385 CXXScopeSpec NewSS, *NewSSPtr = SS;
387 NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
390 if (Correction && (NNS || NewII != &II) &&
391 // Ignore a correction to a template type as the to-be-corrected
392 // identifier is not a template (typo correction for template names
393 // is handled elsewhere).
394 !(getLangOpts().CPlusPlus && NewSSPtr &&
395 isTemplateName(S, *NewSSPtr, false, TemplateName, nullptr, false,
396 Template, MemberOfUnknownSpecialization))) {
397 ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr,
398 isClassName, HasTrailingDot, ObjectTypePtr,
400 WantNontrivialTypeSourceInfo,
401 IsClassTemplateDeductionContext);
403 diagnoseTypo(Correction,
404 PDiag(diag::err_unknown_type_or_class_name_suggest)
405 << Result.getLookupName() << isClassName);
407 SS->MakeTrivial(Context, NNS, SourceRange(NameLoc));
408 *CorrectedII = NewII;
413 // If typo correction failed or was not performed, fall through
415 case LookupResult::FoundOverloaded:
416 case LookupResult::FoundUnresolvedValue:
417 Result.suppressDiagnostics();
420 case LookupResult::Ambiguous:
421 // Recover from type-hiding ambiguities by hiding the type. We'll
422 // do the lookup again when looking for an object, and we can
423 // diagnose the error then. If we don't do this, then the error
424 // about hiding the type will be immediately followed by an error
425 // that only makes sense if the identifier was treated like a type.
426 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) {
427 Result.suppressDiagnostics();
431 // Look to see if we have a type anywhere in the list of results.
432 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end();
433 Res != ResEnd; ++Res) {
434 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res) ||
435 (AllowDeducedTemplate && getAsTypeTemplateDecl(*Res))) {
437 (*Res)->getLocation().getRawEncoding() <
438 IIDecl->getLocation().getRawEncoding())
444 // None of the entities we found is a type, so there is no way
445 // to even assume that the result is a type. In this case, don't
446 // complain about the ambiguity. The parser will either try to
447 // perform this lookup again (e.g., as an object name), which
448 // will produce the ambiguity, or will complain that it expected
450 Result.suppressDiagnostics();
454 // We found a type within the ambiguous lookup; diagnose the
455 // ambiguity and then return that type. This might be the right
456 // answer, or it might not be, but it suppresses any attempt to
457 // perform the name lookup again.
460 case LookupResult::Found:
461 IIDecl = Result.getFoundDecl();
465 assert(IIDecl && "Didn't find decl");
468 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) {
469 // C++ [class.qual]p2: A lookup that would find the injected-class-name
470 // instead names the constructors of the class, except when naming a class.
471 // This is ill-formed when we're not actually forming a ctor or dtor name.
472 auto *LookupRD = dyn_cast_or_null<CXXRecordDecl>(LookupCtx);
473 auto *FoundRD = dyn_cast<CXXRecordDecl>(TD);
474 if (!isClassName && !IsCtorOrDtorName && LookupRD && FoundRD &&
475 FoundRD->isInjectedClassName() &&
476 declaresSameEntity(LookupRD, cast<Decl>(FoundRD->getParent())))
477 Diag(NameLoc, diag::err_out_of_line_qualified_id_type_names_constructor)
480 DiagnoseUseOfDecl(IIDecl, NameLoc);
482 T = Context.getTypeDeclType(TD);
483 MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
484 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) {
485 (void)DiagnoseUseOfDecl(IDecl, NameLoc);
487 T = Context.getObjCInterfaceType(IDecl);
488 } else if (AllowDeducedTemplate) {
489 if (auto *TD = getAsTypeTemplateDecl(IIDecl))
490 T = Context.getDeducedTemplateSpecializationType(TemplateName(TD),
495 // If it's not plausibly a type, suppress diagnostics.
496 Result.suppressDiagnostics();
500 // NOTE: avoid constructing an ElaboratedType(Loc) if this is a
501 // constructor or destructor name (in such a case, the scope specifier
502 // will be attached to the enclosing Expr or Decl node).
503 if (SS && SS->isNotEmpty() && !IsCtorOrDtorName &&
504 !isa<ObjCInterfaceDecl>(IIDecl)) {
505 if (WantNontrivialTypeSourceInfo) {
506 // Construct a type with type-source information.
507 TypeLocBuilder Builder;
508 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
510 T = getElaboratedType(ETK_None, *SS, T);
511 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
512 ElabTL.setElaboratedKeywordLoc(SourceLocation());
513 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context));
514 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
516 T = getElaboratedType(ETK_None, *SS, T);
520 return ParsedType::make(T);
523 // Builds a fake NNS for the given decl context.
524 static NestedNameSpecifier *
525 synthesizeCurrentNestedNameSpecifier(ASTContext &Context, DeclContext *DC) {
526 for (;; DC = DC->getLookupParent()) {
527 DC = DC->getPrimaryContext();
528 auto *ND = dyn_cast<NamespaceDecl>(DC);
529 if (ND && !ND->isInline() && !ND->isAnonymousNamespace())
530 return NestedNameSpecifier::Create(Context, nullptr, ND);
531 else if (auto *RD = dyn_cast<CXXRecordDecl>(DC))
532 return NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
533 RD->getTypeForDecl());
534 else if (isa<TranslationUnitDecl>(DC))
535 return NestedNameSpecifier::GlobalSpecifier(Context);
537 llvm_unreachable("something isn't in TU scope?");
540 /// Find the parent class with dependent bases of the innermost enclosing method
541 /// context. Do not look for enclosing CXXRecordDecls directly, or we will end
542 /// up allowing unqualified dependent type names at class-level, which MSVC
543 /// correctly rejects.
544 static const CXXRecordDecl *
545 findRecordWithDependentBasesOfEnclosingMethod(const DeclContext *DC) {
546 for (; DC && DC->isDependentContext(); DC = DC->getLookupParent()) {
547 DC = DC->getPrimaryContext();
548 if (const auto *MD = dyn_cast<CXXMethodDecl>(DC))
549 if (MD->getParent()->hasAnyDependentBases())
550 return MD->getParent();
555 ParsedType Sema::ActOnMSVCUnknownTypeName(const IdentifierInfo &II,
556 SourceLocation NameLoc,
557 bool IsTemplateTypeArg) {
558 assert(getLangOpts().MSVCCompat && "shouldn't be called in non-MSVC mode");
560 NestedNameSpecifier *NNS = nullptr;
561 if (IsTemplateTypeArg && getCurScope()->isTemplateParamScope()) {
562 // If we weren't able to parse a default template argument, delay lookup
563 // until instantiation time by making a non-dependent DependentTypeName. We
564 // pretend we saw a NestedNameSpecifier referring to the current scope, and
565 // lookup is retried.
566 // FIXME: This hurts our diagnostic quality, since we get errors like "no
567 // type named 'Foo' in 'current_namespace'" when the user didn't write any
569 NNS = synthesizeCurrentNestedNameSpecifier(Context, CurContext);
570 Diag(NameLoc, diag::ext_ms_delayed_template_argument) << &II;
571 } else if (const CXXRecordDecl *RD =
572 findRecordWithDependentBasesOfEnclosingMethod(CurContext)) {
573 // Build a DependentNameType that will perform lookup into RD at
574 // instantiation time.
575 NNS = NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
576 RD->getTypeForDecl());
578 // Diagnose that this identifier was undeclared, and retry the lookup during
579 // template instantiation.
580 Diag(NameLoc, diag::ext_undeclared_unqual_id_with_dependent_base) << &II
583 // This is not a situation that we should recover from.
587 QualType T = Context.getDependentNameType(ETK_None, NNS, &II);
589 // Build type location information. We synthesized the qualifier, so we have
590 // to build a fake NestedNameSpecifierLoc.
591 NestedNameSpecifierLocBuilder NNSLocBuilder;
592 NNSLocBuilder.MakeTrivial(Context, NNS, SourceRange(NameLoc));
593 NestedNameSpecifierLoc QualifierLoc = NNSLocBuilder.getWithLocInContext(Context);
595 TypeLocBuilder Builder;
596 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
597 DepTL.setNameLoc(NameLoc);
598 DepTL.setElaboratedKeywordLoc(SourceLocation());
599 DepTL.setQualifierLoc(QualifierLoc);
600 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
603 /// isTagName() - This method is called *for error recovery purposes only*
604 /// to determine if the specified name is a valid tag name ("struct foo"). If
605 /// so, this returns the TST for the tag corresponding to it (TST_enum,
606 /// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose
607 /// cases in C where the user forgot to specify the tag.
608 DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) {
609 // Do a tag name lookup in this scope.
610 LookupResult R(*this, &II, SourceLocation(), LookupTagName);
611 LookupName(R, S, false);
612 R.suppressDiagnostics();
613 if (R.getResultKind() == LookupResult::Found)
614 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) {
615 switch (TD->getTagKind()) {
616 case TTK_Struct: return DeclSpec::TST_struct;
617 case TTK_Interface: return DeclSpec::TST_interface;
618 case TTK_Union: return DeclSpec::TST_union;
619 case TTK_Class: return DeclSpec::TST_class;
620 case TTK_Enum: return DeclSpec::TST_enum;
624 return DeclSpec::TST_unspecified;
627 /// isMicrosoftMissingTypename - In Microsoft mode, within class scope,
628 /// if a CXXScopeSpec's type is equal to the type of one of the base classes
629 /// then downgrade the missing typename error to a warning.
630 /// This is needed for MSVC compatibility; Example:
632 /// template<class T> class A {
634 /// typedef int TYPE;
636 /// template<class T> class B : public A<T> {
638 /// A<T>::TYPE a; // no typename required because A<T> is a base class.
641 bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) {
642 if (CurContext->isRecord()) {
643 if (SS->getScopeRep()->getKind() == NestedNameSpecifier::Super)
646 const Type *Ty = SS->getScopeRep()->getAsType();
648 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext);
649 for (const auto &Base : RD->bases())
650 if (Ty && Context.hasSameUnqualifiedType(QualType(Ty, 1), Base.getType()))
652 return S->isFunctionPrototypeScope();
654 return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope();
657 void Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II,
658 SourceLocation IILoc,
661 ParsedType &SuggestedType,
662 bool IsTemplateName) {
663 // Don't report typename errors for editor placeholders.
664 if (II->isEditorPlaceholder())
666 // We don't have anything to suggest (yet).
667 SuggestedType = nullptr;
669 // There may have been a typo in the name of the type. Look up typo
670 // results, in case we have something that we can suggest.
671 TypeNameValidatorCCC CCC(/*AllowInvalid=*/false, /*WantClass=*/false,
672 /*AllowTemplates=*/IsTemplateName,
673 /*AllowNonTemplates=*/!IsTemplateName);
674 if (TypoCorrection Corrected =
675 CorrectTypo(DeclarationNameInfo(II, IILoc), LookupOrdinaryName, S, SS,
676 CCC, CTK_ErrorRecovery)) {
677 // FIXME: Support error recovery for the template-name case.
678 bool CanRecover = !IsTemplateName;
679 if (Corrected.isKeyword()) {
680 // We corrected to a keyword.
681 diagnoseTypo(Corrected,
682 PDiag(IsTemplateName ? diag::err_no_template_suggest
683 : diag::err_unknown_typename_suggest)
685 II = Corrected.getCorrectionAsIdentifierInfo();
687 // We found a similarly-named type or interface; suggest that.
688 if (!SS || !SS->isSet()) {
689 diagnoseTypo(Corrected,
690 PDiag(IsTemplateName ? diag::err_no_template_suggest
691 : diag::err_unknown_typename_suggest)
693 } else if (DeclContext *DC = computeDeclContext(*SS, false)) {
694 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
695 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
696 II->getName().equals(CorrectedStr);
697 diagnoseTypo(Corrected,
699 ? diag::err_no_member_template_suggest
700 : diag::err_unknown_nested_typename_suggest)
701 << II << DC << DroppedSpecifier << SS->getRange(),
704 llvm_unreachable("could not have corrected a typo here");
711 if (Corrected.getCorrectionSpecifier())
712 tmpSS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
714 // FIXME: Support class template argument deduction here.
716 getTypeName(*Corrected.getCorrectionAsIdentifierInfo(), IILoc, S,
717 tmpSS.isSet() ? &tmpSS : SS, false, false, nullptr,
718 /*IsCtorOrDtorName=*/false,
719 /*WantNontrivialTypeSourceInfo=*/true);
724 if (getLangOpts().CPlusPlus && !IsTemplateName) {
725 // See if II is a class template that the user forgot to pass arguments to.
727 Name.setIdentifier(II, IILoc);
728 CXXScopeSpec EmptySS;
729 TemplateTy TemplateResult;
730 bool MemberOfUnknownSpecialization;
731 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false,
732 Name, nullptr, true, TemplateResult,
733 MemberOfUnknownSpecialization) == TNK_Type_template) {
734 diagnoseMissingTemplateArguments(TemplateResult.get(), IILoc);
739 // FIXME: Should we move the logic that tries to recover from a missing tag
740 // (struct, union, enum) from Parser::ParseImplicitInt here, instead?
742 if (!SS || (!SS->isSet() && !SS->isInvalid()))
743 Diag(IILoc, IsTemplateName ? diag::err_no_template
744 : diag::err_unknown_typename)
746 else if (DeclContext *DC = computeDeclContext(*SS, false))
747 Diag(IILoc, IsTemplateName ? diag::err_no_member_template
748 : diag::err_typename_nested_not_found)
749 << II << DC << SS->getRange();
750 else if (isDependentScopeSpecifier(*SS)) {
751 unsigned DiagID = diag::err_typename_missing;
752 if (getLangOpts().MSVCCompat && isMicrosoftMissingTypename(SS, S))
753 DiagID = diag::ext_typename_missing;
755 Diag(SS->getRange().getBegin(), DiagID)
756 << SS->getScopeRep() << II->getName()
757 << SourceRange(SS->getRange().getBegin(), IILoc)
758 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename ");
759 SuggestedType = ActOnTypenameType(S, SourceLocation(),
760 *SS, *II, IILoc).get();
762 assert(SS && SS->isInvalid() &&
763 "Invalid scope specifier has already been diagnosed");
767 /// Determine whether the given result set contains either a type name
769 static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) {
770 bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus &&
771 NextToken.is(tok::less);
773 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) {
774 if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I))
777 if (CheckTemplate && isa<TemplateDecl>(*I))
784 static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result,
785 Scope *S, CXXScopeSpec &SS,
786 IdentifierInfo *&Name,
787 SourceLocation NameLoc) {
788 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName);
789 SemaRef.LookupParsedName(R, S, &SS);
790 if (TagDecl *Tag = R.getAsSingle<TagDecl>()) {
791 StringRef FixItTagName;
792 switch (Tag->getTagKind()) {
794 FixItTagName = "class ";
798 FixItTagName = "enum ";
802 FixItTagName = "struct ";
806 FixItTagName = "__interface ";
810 FixItTagName = "union ";
814 StringRef TagName = FixItTagName.drop_back();
815 SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag)
816 << Name << TagName << SemaRef.getLangOpts().CPlusPlus
817 << FixItHint::CreateInsertion(NameLoc, FixItTagName);
819 for (LookupResult::iterator I = Result.begin(), IEnd = Result.end();
821 SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type)
824 // Replace lookup results with just the tag decl.
825 Result.clear(Sema::LookupTagName);
826 SemaRef.LookupParsedName(Result, S, &SS);
833 /// Build a ParsedType for a simple-type-specifier with a nested-name-specifier.
834 static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS,
835 QualType T, SourceLocation NameLoc) {
836 ASTContext &Context = S.Context;
838 TypeLocBuilder Builder;
839 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
841 T = S.getElaboratedType(ETK_None, SS, T);
842 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
843 ElabTL.setElaboratedKeywordLoc(SourceLocation());
844 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
845 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
848 Sema::NameClassification
849 Sema::ClassifyName(Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name,
850 SourceLocation NameLoc, const Token &NextToken,
851 bool IsAddressOfOperand, CorrectionCandidateCallback *CCC) {
852 DeclarationNameInfo NameInfo(Name, NameLoc);
853 ObjCMethodDecl *CurMethod = getCurMethodDecl();
855 if (NextToken.is(tok::coloncolon)) {
856 NestedNameSpecInfo IdInfo(Name, NameLoc, NextToken.getLocation());
857 BuildCXXNestedNameSpecifier(S, IdInfo, false, SS, nullptr, false);
858 } else if (getLangOpts().CPlusPlus && SS.isSet() &&
859 isCurrentClassName(*Name, S, &SS)) {
860 // Per [class.qual]p2, this names the constructors of SS, not the
861 // injected-class-name. We don't have a classification for that.
862 // There's not much point caching this result, since the parser
863 // will reject it later.
864 return NameClassification::Unknown();
867 LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName);
868 LookupParsedName(Result, S, &SS, !CurMethod);
870 // For unqualified lookup in a class template in MSVC mode, look into
871 // dependent base classes where the primary class template is known.
872 if (Result.empty() && SS.isEmpty() && getLangOpts().MSVCCompat) {
873 if (ParsedType TypeInBase =
874 recoverFromTypeInKnownDependentBase(*this, *Name, NameLoc))
878 // Perform lookup for Objective-C instance variables (including automatically
879 // synthesized instance variables), if we're in an Objective-C method.
880 // FIXME: This lookup really, really needs to be folded in to the normal
881 // unqualified lookup mechanism.
882 if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) {
883 ExprResult E = LookupInObjCMethod(Result, S, Name, true);
884 if (E.get() || E.isInvalid())
888 bool SecondTry = false;
889 bool IsFilteredTemplateName = false;
892 switch (Result.getResultKind()) {
893 case LookupResult::NotFound:
894 // If an unqualified-id is followed by a '(', then we have a function
896 if (!SS.isSet() && NextToken.is(tok::l_paren)) {
897 // In C++, this is an ADL-only call.
899 if (getLangOpts().CPlusPlus)
900 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true);
903 // If the expression that precedes the parenthesized argument list in a
904 // function call consists solely of an identifier, and if no
905 // declaration is visible for this identifier, the identifier is
906 // implicitly declared exactly as if, in the innermost block containing
907 // the function call, the declaration
909 // extern int identifier ();
913 // We also allow this in C99 as an extension.
914 if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) {
916 Result.resolveKind();
917 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false);
921 if (getLangOpts().CPlusPlus2a && !SS.isSet() && NextToken.is(tok::less)) {
922 // In C++20 onwards, this could be an ADL-only call to a function
923 // template, and we're required to assume that this is a template name.
925 // FIXME: Find a way to still do typo correction in this case.
926 TemplateName Template =
927 Context.getAssumedTemplateName(NameInfo.getName());
928 return NameClassification::UndeclaredTemplate(Template);
931 // In C, we first see whether there is a tag type by the same name, in
932 // which case it's likely that the user just forgot to write "enum",
933 // "struct", or "union".
934 if (!getLangOpts().CPlusPlus && !SecondTry &&
935 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
939 // Perform typo correction to determine if there is another name that is
940 // close to this name.
941 if (!SecondTry && CCC) {
943 if (TypoCorrection Corrected =
944 CorrectTypo(Result.getLookupNameInfo(), Result.getLookupKind(), S,
945 &SS, *CCC, CTK_ErrorRecovery)) {
946 unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest;
947 unsigned QualifiedDiag = diag::err_no_member_suggest;
949 NamedDecl *FirstDecl = Corrected.getFoundDecl();
950 NamedDecl *UnderlyingFirstDecl = Corrected.getCorrectionDecl();
951 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
952 UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) {
953 UnqualifiedDiag = diag::err_no_template_suggest;
954 QualifiedDiag = diag::err_no_member_template_suggest;
955 } else if (UnderlyingFirstDecl &&
956 (isa<TypeDecl>(UnderlyingFirstDecl) ||
957 isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) ||
958 isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) {
959 UnqualifiedDiag = diag::err_unknown_typename_suggest;
960 QualifiedDiag = diag::err_unknown_nested_typename_suggest;
964 diagnoseTypo(Corrected, PDiag(UnqualifiedDiag) << Name);
965 } else {// FIXME: is this even reachable? Test it.
966 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
967 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
968 Name->getName().equals(CorrectedStr);
969 diagnoseTypo(Corrected, PDiag(QualifiedDiag)
970 << Name << computeDeclContext(SS, false)
971 << DroppedSpecifier << SS.getRange());
974 // Update the name, so that the caller has the new name.
975 Name = Corrected.getCorrectionAsIdentifierInfo();
977 // Typo correction corrected to a keyword.
978 if (Corrected.isKeyword())
981 // Also update the LookupResult...
982 // FIXME: This should probably go away at some point
984 Result.setLookupName(Corrected.getCorrection());
986 Result.addDecl(FirstDecl);
988 // If we found an Objective-C instance variable, let
989 // LookupInObjCMethod build the appropriate expression to
990 // reference the ivar.
991 // FIXME: This is a gross hack.
992 if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) {
994 ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier()));
1002 // We failed to correct; just fall through and let the parser deal with it.
1003 Result.suppressDiagnostics();
1004 return NameClassification::Unknown();
1006 case LookupResult::NotFoundInCurrentInstantiation: {
1007 // We performed name lookup into the current instantiation, and there were
1008 // dependent bases, so we treat this result the same way as any other
1009 // dependent nested-name-specifier.
1011 // C++ [temp.res]p2:
1012 // A name used in a template declaration or definition and that is
1013 // dependent on a template-parameter is assumed not to name a type
1014 // unless the applicable name lookup finds a type name or the name is
1015 // qualified by the keyword typename.
1017 // FIXME: If the next token is '<', we might want to ask the parser to
1018 // perform some heroics to see if we actually have a
1019 // template-argument-list, which would indicate a missing 'template'
1021 return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(),
1022 NameInfo, IsAddressOfOperand,
1023 /*TemplateArgs=*/nullptr);
1026 case LookupResult::Found:
1027 case LookupResult::FoundOverloaded:
1028 case LookupResult::FoundUnresolvedValue:
1031 case LookupResult::Ambiguous:
1032 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
1033 hasAnyAcceptableTemplateNames(Result, /*AllowFunctionTemplates=*/true,
1034 /*AllowDependent=*/false)) {
1035 // C++ [temp.local]p3:
1036 // A lookup that finds an injected-class-name (10.2) can result in an
1037 // ambiguity in certain cases (for example, if it is found in more than
1038 // one base class). If all of the injected-class-names that are found
1039 // refer to specializations of the same class template, and if the name
1040 // is followed by a template-argument-list, the reference refers to the
1041 // class template itself and not a specialization thereof, and is not
1044 // This filtering can make an ambiguous result into an unambiguous one,
1045 // so try again after filtering out template names.
1046 FilterAcceptableTemplateNames(Result);
1047 if (!Result.isAmbiguous()) {
1048 IsFilteredTemplateName = true;
1053 // Diagnose the ambiguity and return an error.
1054 return NameClassification::Error();
1057 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
1058 (IsFilteredTemplateName ||
1059 hasAnyAcceptableTemplateNames(
1060 Result, /*AllowFunctionTemplates=*/true,
1061 /*AllowDependent=*/false,
1062 /*AllowNonTemplateFunctions*/ !SS.isSet() &&
1063 getLangOpts().CPlusPlus2a))) {
1064 // C++ [temp.names]p3:
1065 // After name lookup (3.4) finds that a name is a template-name or that
1066 // an operator-function-id or a literal- operator-id refers to a set of
1067 // overloaded functions any member of which is a function template if
1068 // this is followed by a <, the < is always taken as the delimiter of a
1069 // template-argument-list and never as the less-than operator.
1070 // C++2a [temp.names]p2:
1071 // A name is also considered to refer to a template if it is an
1072 // unqualified-id followed by a < and name lookup finds either one
1073 // or more functions or finds nothing.
1074 if (!IsFilteredTemplateName)
1075 FilterAcceptableTemplateNames(Result);
1077 bool IsFunctionTemplate;
1079 TemplateName Template;
1080 if (Result.end() - Result.begin() > 1) {
1081 IsFunctionTemplate = true;
1082 Template = Context.getOverloadedTemplateName(Result.begin(),
1084 } else if (!Result.empty()) {
1085 auto *TD = cast<TemplateDecl>(getAsTemplateNameDecl(
1086 *Result.begin(), /*AllowFunctionTemplates=*/true,
1087 /*AllowDependent=*/false));
1088 IsFunctionTemplate = isa<FunctionTemplateDecl>(TD);
1089 IsVarTemplate = isa<VarTemplateDecl>(TD);
1091 if (SS.isSet() && !SS.isInvalid())
1093 Context.getQualifiedTemplateName(SS.getScopeRep(),
1094 /*TemplateKeyword=*/false, TD);
1096 Template = TemplateName(TD);
1098 // All results were non-template functions. This is a function template
1100 IsFunctionTemplate = true;
1101 Template = Context.getAssumedTemplateName(NameInfo.getName());
1104 if (IsFunctionTemplate) {
1105 // Function templates always go through overload resolution, at which
1106 // point we'll perform the various checks (e.g., accessibility) we need
1107 // to based on which function we selected.
1108 Result.suppressDiagnostics();
1110 return NameClassification::FunctionTemplate(Template);
1113 return IsVarTemplate ? NameClassification::VarTemplate(Template)
1114 : NameClassification::TypeTemplate(Template);
1117 NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl();
1118 if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) {
1119 DiagnoseUseOfDecl(Type, NameLoc);
1120 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
1121 QualType T = Context.getTypeDeclType(Type);
1122 if (SS.isNotEmpty())
1123 return buildNestedType(*this, SS, T, NameLoc);
1124 return ParsedType::make(T);
1127 ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl);
1129 // FIXME: It's unfortunate that we don't have a Type node for handling this.
1130 if (ObjCCompatibleAliasDecl *Alias =
1131 dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl))
1132 Class = Alias->getClassInterface();
1136 DiagnoseUseOfDecl(Class, NameLoc);
1138 if (NextToken.is(tok::period)) {
1139 // Interface. <something> is parsed as a property reference expression.
1140 // Just return "unknown" as a fall-through for now.
1141 Result.suppressDiagnostics();
1142 return NameClassification::Unknown();
1145 QualType T = Context.getObjCInterfaceType(Class);
1146 return ParsedType::make(T);
1149 // We can have a type template here if we're classifying a template argument.
1150 if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl) &&
1151 !isa<VarTemplateDecl>(FirstDecl))
1152 return NameClassification::TypeTemplate(
1153 TemplateName(cast<TemplateDecl>(FirstDecl)));
1155 // Check for a tag type hidden by a non-type decl in a few cases where it
1156 // seems likely a type is wanted instead of the non-type that was found.
1157 bool NextIsOp = NextToken.isOneOf(tok::amp, tok::star);
1158 if ((NextToken.is(tok::identifier) ||
1160 FirstDecl->getUnderlyingDecl()->isFunctionOrFunctionTemplate())) &&
1161 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
1162 TypeDecl *Type = Result.getAsSingle<TypeDecl>();
1163 DiagnoseUseOfDecl(Type, NameLoc);
1164 QualType T = Context.getTypeDeclType(Type);
1165 if (SS.isNotEmpty())
1166 return buildNestedType(*this, SS, T, NameLoc);
1167 return ParsedType::make(T);
1170 if (FirstDecl->isCXXClassMember())
1171 return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result,
1174 bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren));
1175 return BuildDeclarationNameExpr(SS, Result, ADL);
1178 Sema::TemplateNameKindForDiagnostics
1179 Sema::getTemplateNameKindForDiagnostics(TemplateName Name) {
1180 auto *TD = Name.getAsTemplateDecl();
1182 return TemplateNameKindForDiagnostics::DependentTemplate;
1183 if (isa<ClassTemplateDecl>(TD))
1184 return TemplateNameKindForDiagnostics::ClassTemplate;
1185 if (isa<FunctionTemplateDecl>(TD))
1186 return TemplateNameKindForDiagnostics::FunctionTemplate;
1187 if (isa<VarTemplateDecl>(TD))
1188 return TemplateNameKindForDiagnostics::VarTemplate;
1189 if (isa<TypeAliasTemplateDecl>(TD))
1190 return TemplateNameKindForDiagnostics::AliasTemplate;
1191 if (isa<TemplateTemplateParmDecl>(TD))
1192 return TemplateNameKindForDiagnostics::TemplateTemplateParam;
1193 if (isa<ConceptDecl>(TD))
1194 return TemplateNameKindForDiagnostics::Concept;
1195 return TemplateNameKindForDiagnostics::DependentTemplate;
1198 // Determines the context to return to after temporarily entering a
1199 // context. This depends in an unnecessarily complicated way on the
1200 // exact ordering of callbacks from the parser.
1201 DeclContext *Sema::getContainingDC(DeclContext *DC) {
1203 // Functions defined inline within classes aren't parsed until we've
1204 // finished parsing the top-level class, so the top-level class is
1205 // the context we'll need to return to.
1206 // A Lambda call operator whose parent is a class must not be treated
1207 // as an inline member function. A Lambda can be used legally
1208 // either as an in-class member initializer or a default argument. These
1209 // are parsed once the class has been marked complete and so the containing
1210 // context would be the nested class (when the lambda is defined in one);
1211 // If the class is not complete, then the lambda is being used in an
1212 // ill-formed fashion (such as to specify the width of a bit-field, or
1213 // in an array-bound) - in which case we still want to return the
1214 // lexically containing DC (which could be a nested class).
1215 if (isa<FunctionDecl>(DC) && !isLambdaCallOperator(DC)) {
1216 DC = DC->getLexicalParent();
1218 // A function not defined within a class will always return to its
1220 if (!isa<CXXRecordDecl>(DC))
1223 // A C++ inline method/friend is parsed *after* the topmost class
1224 // it was declared in is fully parsed ("complete"); the topmost
1225 // class is the context we need to return to.
1226 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent()))
1229 // Return the declaration context of the topmost class the inline method is
1234 return DC->getLexicalParent();
1237 void Sema::PushDeclContext(Scope *S, DeclContext *DC) {
1238 assert(getContainingDC(DC) == CurContext &&
1239 "The next DeclContext should be lexically contained in the current one.");
1244 void Sema::PopDeclContext() {
1245 assert(CurContext && "DeclContext imbalance!");
1247 CurContext = getContainingDC(CurContext);
1248 assert(CurContext && "Popped translation unit!");
1251 Sema::SkippedDefinitionContext Sema::ActOnTagStartSkippedDefinition(Scope *S,
1253 // Unlike PushDeclContext, the context to which we return is not necessarily
1254 // the containing DC of TD, because the new context will be some pre-existing
1255 // TagDecl definition instead of a fresh one.
1256 auto Result = static_cast<SkippedDefinitionContext>(CurContext);
1257 CurContext = cast<TagDecl>(D)->getDefinition();
1258 assert(CurContext && "skipping definition of undefined tag");
1259 // Start lookups from the parent of the current context; we don't want to look
1260 // into the pre-existing complete definition.
1261 S->setEntity(CurContext->getLookupParent());
1265 void Sema::ActOnTagFinishSkippedDefinition(SkippedDefinitionContext Context) {
1266 CurContext = static_cast<decltype(CurContext)>(Context);
1269 /// EnterDeclaratorContext - Used when we must lookup names in the context
1270 /// of a declarator's nested name specifier.
1272 void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) {
1273 // C++0x [basic.lookup.unqual]p13:
1274 // A name used in the definition of a static data member of class
1275 // X (after the qualified-id of the static member) is looked up as
1276 // if the name was used in a member function of X.
1277 // C++0x [basic.lookup.unqual]p14:
1278 // If a variable member of a namespace is defined outside of the
1279 // scope of its namespace then any name used in the definition of
1280 // the variable member (after the declarator-id) is looked up as
1281 // if the definition of the variable member occurred in its
1283 // Both of these imply that we should push a scope whose context
1284 // is the semantic context of the declaration. We can't use
1285 // PushDeclContext here because that context is not necessarily
1286 // lexically contained in the current context. Fortunately,
1287 // the containing scope should have the appropriate information.
1289 assert(!S->getEntity() && "scope already has entity");
1292 Scope *Ancestor = S->getParent();
1293 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1294 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch");
1301 void Sema::ExitDeclaratorContext(Scope *S) {
1302 assert(S->getEntity() == CurContext && "Context imbalance!");
1304 // Switch back to the lexical context. The safety of this is
1305 // enforced by an assert in EnterDeclaratorContext.
1306 Scope *Ancestor = S->getParent();
1307 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1308 CurContext = Ancestor->getEntity();
1310 // We don't need to do anything with the scope, which is going to
1314 void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) {
1315 // We assume that the caller has already called
1316 // ActOnReenterTemplateScope so getTemplatedDecl() works.
1317 FunctionDecl *FD = D->getAsFunction();
1321 // Same implementation as PushDeclContext, but enters the context
1322 // from the lexical parent, rather than the top-level class.
1323 assert(CurContext == FD->getLexicalParent() &&
1324 "The next DeclContext should be lexically contained in the current one.");
1326 S->setEntity(CurContext);
1328 for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) {
1329 ParmVarDecl *Param = FD->getParamDecl(P);
1330 // If the parameter has an identifier, then add it to the scope
1331 if (Param->getIdentifier()) {
1333 IdResolver.AddDecl(Param);
1338 void Sema::ActOnExitFunctionContext() {
1339 // Same implementation as PopDeclContext, but returns to the lexical parent,
1340 // rather than the top-level class.
1341 assert(CurContext && "DeclContext imbalance!");
1342 CurContext = CurContext->getLexicalParent();
1343 assert(CurContext && "Popped translation unit!");
1346 /// Determine whether we allow overloading of the function
1347 /// PrevDecl with another declaration.
1349 /// This routine determines whether overloading is possible, not
1350 /// whether some new function is actually an overload. It will return
1351 /// true in C++ (where we can always provide overloads) or, as an
1352 /// extension, in C when the previous function is already an
1353 /// overloaded function declaration or has the "overloadable"
1355 static bool AllowOverloadingOfFunction(LookupResult &Previous,
1356 ASTContext &Context,
1357 const FunctionDecl *New) {
1358 if (Context.getLangOpts().CPlusPlus)
1361 if (Previous.getResultKind() == LookupResult::FoundOverloaded)
1364 return Previous.getResultKind() == LookupResult::Found &&
1365 (Previous.getFoundDecl()->hasAttr<OverloadableAttr>() ||
1366 New->hasAttr<OverloadableAttr>());
1369 /// Add this decl to the scope shadowed decl chains.
1370 void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) {
1371 // Move up the scope chain until we find the nearest enclosing
1372 // non-transparent context. The declaration will be introduced into this
1374 while (S->getEntity() && S->getEntity()->isTransparentContext())
1377 // Add scoped declarations into their context, so that they can be
1378 // found later. Declarations without a context won't be inserted
1379 // into any context.
1381 CurContext->addDecl(D);
1383 // Out-of-line definitions shouldn't be pushed into scope in C++, unless they
1384 // are function-local declarations.
1385 if (getLangOpts().CPlusPlus && D->isOutOfLine() &&
1386 !D->getDeclContext()->getRedeclContext()->Equals(
1387 D->getLexicalDeclContext()->getRedeclContext()) &&
1388 !D->getLexicalDeclContext()->isFunctionOrMethod())
1391 // Template instantiations should also not be pushed into scope.
1392 if (isa<FunctionDecl>(D) &&
1393 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization())
1396 // If this replaces anything in the current scope,
1397 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()),
1398 IEnd = IdResolver.end();
1399 for (; I != IEnd; ++I) {
1400 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) {
1402 IdResolver.RemoveDecl(*I);
1404 // Should only need to replace one decl.
1411 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) {
1412 // Implicitly-generated labels may end up getting generated in an order that
1413 // isn't strictly lexical, which breaks name lookup. Be careful to insert
1414 // the label at the appropriate place in the identifier chain.
1415 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) {
1416 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext();
1417 if (IDC == CurContext) {
1418 if (!S->isDeclScope(*I))
1420 } else if (IDC->Encloses(CurContext))
1424 IdResolver.InsertDeclAfter(I, D);
1426 IdResolver.AddDecl(D);
1430 bool Sema::isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S,
1431 bool AllowInlineNamespace) {
1432 return IdResolver.isDeclInScope(D, Ctx, S, AllowInlineNamespace);
1435 Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) {
1436 DeclContext *TargetDC = DC->getPrimaryContext();
1438 if (DeclContext *ScopeDC = S->getEntity())
1439 if (ScopeDC->getPrimaryContext() == TargetDC)
1441 } while ((S = S->getParent()));
1446 static bool isOutOfScopePreviousDeclaration(NamedDecl *,
1450 /// Filters out lookup results that don't fall within the given scope
1451 /// as determined by isDeclInScope.
1452 void Sema::FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S,
1453 bool ConsiderLinkage,
1454 bool AllowInlineNamespace) {
1455 LookupResult::Filter F = R.makeFilter();
1456 while (F.hasNext()) {
1457 NamedDecl *D = F.next();
1459 if (isDeclInScope(D, Ctx, S, AllowInlineNamespace))
1462 if (ConsiderLinkage && isOutOfScopePreviousDeclaration(D, Ctx, Context))
1471 /// We've determined that \p New is a redeclaration of \p Old. Check that they
1472 /// have compatible owning modules.
1473 bool Sema::CheckRedeclarationModuleOwnership(NamedDecl *New, NamedDecl *Old) {
1474 // FIXME: The Modules TS is not clear about how friend declarations are
1475 // to be treated. It's not meaningful to have different owning modules for
1476 // linkage in redeclarations of the same entity, so for now allow the
1477 // redeclaration and change the owning modules to match.
1478 if (New->getFriendObjectKind() &&
1479 Old->getOwningModuleForLinkage() != New->getOwningModuleForLinkage()) {
1480 New->setLocalOwningModule(Old->getOwningModule());
1481 makeMergedDefinitionVisible(New);
1485 Module *NewM = New->getOwningModule();
1486 Module *OldM = Old->getOwningModule();
1488 if (NewM && NewM->Kind == Module::PrivateModuleFragment)
1489 NewM = NewM->Parent;
1490 if (OldM && OldM->Kind == Module::PrivateModuleFragment)
1491 OldM = OldM->Parent;
1496 bool NewIsModuleInterface = NewM && NewM->isModulePurview();
1497 bool OldIsModuleInterface = OldM && OldM->isModulePurview();
1498 if (NewIsModuleInterface || OldIsModuleInterface) {
1499 // C++ Modules TS [basic.def.odr] 6.2/6.7 [sic]:
1500 // if a declaration of D [...] appears in the purview of a module, all
1501 // other such declarations shall appear in the purview of the same module
1502 Diag(New->getLocation(), diag::err_mismatched_owning_module)
1504 << NewIsModuleInterface
1505 << (NewIsModuleInterface ? NewM->getFullModuleName() : "")
1506 << OldIsModuleInterface
1507 << (OldIsModuleInterface ? OldM->getFullModuleName() : "");
1508 Diag(Old->getLocation(), diag::note_previous_declaration);
1509 New->setInvalidDecl();
1516 static bool isUsingDecl(NamedDecl *D) {
1517 return isa<UsingShadowDecl>(D) ||
1518 isa<UnresolvedUsingTypenameDecl>(D) ||
1519 isa<UnresolvedUsingValueDecl>(D);
1522 /// Removes using shadow declarations from the lookup results.
1523 static void RemoveUsingDecls(LookupResult &R) {
1524 LookupResult::Filter F = R.makeFilter();
1526 if (isUsingDecl(F.next()))
1532 /// Check for this common pattern:
1535 /// S(const S&); // DO NOT IMPLEMENT
1536 /// void operator=(const S&); // DO NOT IMPLEMENT
1539 static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) {
1540 // FIXME: Should check for private access too but access is set after we get
1542 if (D->doesThisDeclarationHaveABody())
1545 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D))
1546 return CD->isCopyConstructor();
1547 return D->isCopyAssignmentOperator();
1550 // We need this to handle
1553 // void *foo() { return 0; }
1556 // When we see foo we don't know if after the typedef we will get 'A' or '*A'
1557 // for example. If 'A', foo will have external linkage. If we have '*A',
1558 // foo will have no linkage. Since we can't know until we get to the end
1559 // of the typedef, this function finds out if D might have non-external linkage.
1560 // Callers should verify at the end of the TU if it D has external linkage or
1562 bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) {
1563 const DeclContext *DC = D->getDeclContext();
1564 while (!DC->isTranslationUnit()) {
1565 if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){
1566 if (!RD->hasNameForLinkage())
1569 DC = DC->getParent();
1572 return !D->isExternallyVisible();
1575 // FIXME: This needs to be refactored; some other isInMainFile users want
1577 static bool isMainFileLoc(const Sema &S, SourceLocation Loc) {
1578 if (S.TUKind != TU_Complete)
1580 return S.SourceMgr.isInMainFile(Loc);
1583 bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
1586 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>())
1589 // Ignore all entities declared within templates, and out-of-line definitions
1590 // of members of class templates.
1591 if (D->getDeclContext()->isDependentContext() ||
1592 D->getLexicalDeclContext()->isDependentContext())
1595 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1596 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1598 // A non-out-of-line declaration of a member specialization was implicitly
1599 // instantiated; it's the out-of-line declaration that we're interested in.
1600 if (FD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization &&
1601 FD->getMemberSpecializationInfo() && !FD->isOutOfLine())
1604 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
1605 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD))
1608 // 'static inline' functions are defined in headers; don't warn.
1609 if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation()))
1613 if (FD->doesThisDeclarationHaveABody() &&
1614 Context.DeclMustBeEmitted(FD))
1616 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1617 // Constants and utility variables are defined in headers with internal
1618 // linkage; don't warn. (Unlike functions, there isn't a convenient marker
1620 if (!isMainFileLoc(*this, VD->getLocation()))
1623 if (Context.DeclMustBeEmitted(VD))
1626 if (VD->isStaticDataMember() &&
1627 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1629 if (VD->isStaticDataMember() &&
1630 VD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization &&
1631 VD->getMemberSpecializationInfo() && !VD->isOutOfLine())
1634 if (VD->isInline() && !isMainFileLoc(*this, VD->getLocation()))
1640 // Only warn for unused decls internal to the translation unit.
1641 // FIXME: This seems like a bogus check; it suppresses -Wunused-function
1642 // for inline functions defined in the main source file, for instance.
1643 return mightHaveNonExternalLinkage(D);
1646 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
1650 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1651 const FunctionDecl *First = FD->getFirstDecl();
1652 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1653 return; // First should already be in the vector.
1656 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1657 const VarDecl *First = VD->getFirstDecl();
1658 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1659 return; // First should already be in the vector.
1662 if (ShouldWarnIfUnusedFileScopedDecl(D))
1663 UnusedFileScopedDecls.push_back(D);
1666 static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
1667 if (D->isInvalidDecl())
1670 bool Referenced = false;
1671 if (auto *DD = dyn_cast<DecompositionDecl>(D)) {
1672 // For a decomposition declaration, warn if none of the bindings are
1673 // referenced, instead of if the variable itself is referenced (which
1674 // it is, by the bindings' expressions).
1675 for (auto *BD : DD->bindings()) {
1676 if (BD->isReferenced()) {
1681 } else if (!D->getDeclName()) {
1683 } else if (D->isReferenced() || D->isUsed()) {
1687 if (Referenced || D->hasAttr<UnusedAttr>() ||
1688 D->hasAttr<ObjCPreciseLifetimeAttr>())
1691 if (isa<LabelDecl>(D))
1694 // Except for labels, we only care about unused decls that are local to
1696 bool WithinFunction = D->getDeclContext()->isFunctionOrMethod();
1697 if (const auto *R = dyn_cast<CXXRecordDecl>(D->getDeclContext()))
1698 // For dependent types, the diagnostic is deferred.
1700 WithinFunction || (R->isLocalClass() && !R->isDependentType());
1701 if (!WithinFunction)
1704 if (isa<TypedefNameDecl>(D))
1707 // White-list anything that isn't a local variable.
1708 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D))
1711 // Types of valid local variables should be complete, so this should succeed.
1712 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1714 // White-list anything with an __attribute__((unused)) type.
1715 const auto *Ty = VD->getType().getTypePtr();
1717 // Only look at the outermost level of typedef.
1718 if (const TypedefType *TT = Ty->getAs<TypedefType>()) {
1719 if (TT->getDecl()->hasAttr<UnusedAttr>())
1723 // If we failed to complete the type for some reason, or if the type is
1724 // dependent, don't diagnose the variable.
1725 if (Ty->isIncompleteType() || Ty->isDependentType())
1728 // Look at the element type to ensure that the warning behaviour is
1729 // consistent for both scalars and arrays.
1730 Ty = Ty->getBaseElementTypeUnsafe();
1732 if (const TagType *TT = Ty->getAs<TagType>()) {
1733 const TagDecl *Tag = TT->getDecl();
1734 if (Tag->hasAttr<UnusedAttr>())
1737 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) {
1738 if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>())
1741 if (const Expr *Init = VD->getInit()) {
1742 if (const ExprWithCleanups *Cleanups =
1743 dyn_cast<ExprWithCleanups>(Init))
1744 Init = Cleanups->getSubExpr();
1745 const CXXConstructExpr *Construct =
1746 dyn_cast<CXXConstructExpr>(Init);
1747 if (Construct && !Construct->isElidable()) {
1748 CXXConstructorDecl *CD = Construct->getConstructor();
1749 if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>() &&
1750 (VD->getInit()->isValueDependent() || !VD->evaluateValue()))
1757 // TODO: __attribute__((unused)) templates?
1763 static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx,
1765 if (isa<LabelDecl>(D)) {
1766 SourceLocation AfterColon = Lexer::findLocationAfterToken(
1767 D->getEndLoc(), tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(),
1769 if (AfterColon.isInvalid())
1771 Hint = FixItHint::CreateRemoval(
1772 CharSourceRange::getCharRange(D->getBeginLoc(), AfterColon));
1776 void Sema::DiagnoseUnusedNestedTypedefs(const RecordDecl *D) {
1777 if (D->getTypeForDecl()->isDependentType())
1780 for (auto *TmpD : D->decls()) {
1781 if (const auto *T = dyn_cast<TypedefNameDecl>(TmpD))
1782 DiagnoseUnusedDecl(T);
1783 else if(const auto *R = dyn_cast<RecordDecl>(TmpD))
1784 DiagnoseUnusedNestedTypedefs(R);
1788 /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used
1789 /// unless they are marked attr(unused).
1790 void Sema::DiagnoseUnusedDecl(const NamedDecl *D) {
1791 if (!ShouldDiagnoseUnusedDecl(D))
1794 if (auto *TD = dyn_cast<TypedefNameDecl>(D)) {
1795 // typedefs can be referenced later on, so the diagnostics are emitted
1796 // at end-of-translation-unit.
1797 UnusedLocalTypedefNameCandidates.insert(TD);
1802 GenerateFixForUnusedDecl(D, Context, Hint);
1805 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable())
1806 DiagID = diag::warn_unused_exception_param;
1807 else if (isa<LabelDecl>(D))
1808 DiagID = diag::warn_unused_label;
1810 DiagID = diag::warn_unused_variable;
1812 Diag(D->getLocation(), DiagID) << D << Hint;
1815 static void CheckPoppedLabel(LabelDecl *L, Sema &S) {
1816 // Verify that we have no forward references left. If so, there was a goto
1817 // or address of a label taken, but no definition of it. Label fwd
1818 // definitions are indicated with a null substmt which is also not a resolved
1819 // MS inline assembly label name.
1820 bool Diagnose = false;
1821 if (L->isMSAsmLabel())
1822 Diagnose = !L->isResolvedMSAsmLabel();
1824 Diagnose = L->getStmt() == nullptr;
1826 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName();
1829 void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) {
1830 S->mergeNRVOIntoParent();
1832 if (S->decl_empty()) return;
1833 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) &&
1834 "Scope shouldn't contain decls!");
1836 for (auto *TmpD : S->decls()) {
1837 assert(TmpD && "This decl didn't get pushed??");
1839 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?");
1840 NamedDecl *D = cast<NamedDecl>(TmpD);
1842 // Diagnose unused variables in this scope.
1843 if (!S->hasUnrecoverableErrorOccurred()) {
1844 DiagnoseUnusedDecl(D);
1845 if (const auto *RD = dyn_cast<RecordDecl>(D))
1846 DiagnoseUnusedNestedTypedefs(RD);
1849 if (!D->getDeclName()) continue;
1851 // If this was a forward reference to a label, verify it was defined.
1852 if (LabelDecl *LD = dyn_cast<LabelDecl>(D))
1853 CheckPoppedLabel(LD, *this);
1855 // Remove this name from our lexical scope, and warn on it if we haven't
1857 IdResolver.RemoveDecl(D);
1858 auto ShadowI = ShadowingDecls.find(D);
1859 if (ShadowI != ShadowingDecls.end()) {
1860 if (const auto *FD = dyn_cast<FieldDecl>(ShadowI->second)) {
1861 Diag(D->getLocation(), diag::warn_ctor_parm_shadows_field)
1862 << D << FD << FD->getParent();
1863 Diag(FD->getLocation(), diag::note_previous_declaration);
1865 ShadowingDecls.erase(ShadowI);
1870 /// Look for an Objective-C class in the translation unit.
1872 /// \param Id The name of the Objective-C class we're looking for. If
1873 /// typo-correction fixes this name, the Id will be updated
1874 /// to the fixed name.
1876 /// \param IdLoc The location of the name in the translation unit.
1878 /// \param DoTypoCorrection If true, this routine will attempt typo correction
1879 /// if there is no class with the given name.
1881 /// \returns The declaration of the named Objective-C class, or NULL if the
1882 /// class could not be found.
1883 ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id,
1884 SourceLocation IdLoc,
1885 bool DoTypoCorrection) {
1886 // The third "scope" argument is 0 since we aren't enabling lazy built-in
1887 // creation from this context.
1888 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName);
1890 if (!IDecl && DoTypoCorrection) {
1891 // Perform typo correction at the given location, but only if we
1892 // find an Objective-C class name.
1893 DeclFilterCCC<ObjCInterfaceDecl> CCC{};
1894 if (TypoCorrection C =
1895 CorrectTypo(DeclarationNameInfo(Id, IdLoc), LookupOrdinaryName,
1896 TUScope, nullptr, CCC, CTK_ErrorRecovery)) {
1897 diagnoseTypo(C, PDiag(diag::err_undef_interface_suggest) << Id);
1898 IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>();
1899 Id = IDecl->getIdentifier();
1902 ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl);
1903 // This routine must always return a class definition, if any.
1904 if (Def && Def->getDefinition())
1905 Def = Def->getDefinition();
1909 /// getNonFieldDeclScope - Retrieves the innermost scope, starting
1910 /// from S, where a non-field would be declared. This routine copes
1911 /// with the difference between C and C++ scoping rules in structs and
1912 /// unions. For example, the following code is well-formed in C but
1913 /// ill-formed in C++:
1919 /// void test_S6() {
1924 /// For the declaration of BAR, this routine will return a different
1925 /// scope. The scope S will be the scope of the unnamed enumeration
1926 /// within S6. In C++, this routine will return the scope associated
1927 /// with S6, because the enumeration's scope is a transparent
1928 /// context but structures can contain non-field names. In C, this
1929 /// routine will return the translation unit scope, since the
1930 /// enumeration's scope is a transparent context and structures cannot
1931 /// contain non-field names.
1932 Scope *Sema::getNonFieldDeclScope(Scope *S) {
1933 while (((S->getFlags() & Scope::DeclScope) == 0) ||
1934 (S->getEntity() && S->getEntity()->isTransparentContext()) ||
1935 (S->isClassScope() && !getLangOpts().CPlusPlus))
1940 /// Looks up the declaration of "struct objc_super" and
1941 /// saves it for later use in building builtin declaration of
1942 /// objc_msgSendSuper and objc_msgSendSuper_stret. If no such
1943 /// pre-existing declaration exists no action takes place.
1944 static void LookupPredefedObjCSuperType(Sema &ThisSema, Scope *S,
1945 IdentifierInfo *II) {
1946 if (!II->isStr("objc_msgSendSuper"))
1948 ASTContext &Context = ThisSema.Context;
1950 LookupResult Result(ThisSema, &Context.Idents.get("objc_super"),
1951 SourceLocation(), Sema::LookupTagName);
1952 ThisSema.LookupName(Result, S);
1953 if (Result.getResultKind() == LookupResult::Found)
1954 if (const TagDecl *TD = Result.getAsSingle<TagDecl>())
1955 Context.setObjCSuperType(Context.getTagDeclType(TD));
1958 static StringRef getHeaderName(Builtin::Context &BuiltinInfo, unsigned ID,
1959 ASTContext::GetBuiltinTypeError Error) {
1961 case ASTContext::GE_None:
1963 case ASTContext::GE_Missing_type:
1964 return BuiltinInfo.getHeaderName(ID);
1965 case ASTContext::GE_Missing_stdio:
1967 case ASTContext::GE_Missing_setjmp:
1969 case ASTContext::GE_Missing_ucontext:
1970 return "ucontext.h";
1972 llvm_unreachable("unhandled error kind");
1975 /// LazilyCreateBuiltin - The specified Builtin-ID was first used at
1976 /// file scope. lazily create a decl for it. ForRedeclaration is true
1977 /// if we're creating this built-in in anticipation of redeclaring the
1979 NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID,
1980 Scope *S, bool ForRedeclaration,
1981 SourceLocation Loc) {
1982 LookupPredefedObjCSuperType(*this, S, II);
1984 ASTContext::GetBuiltinTypeError Error;
1985 QualType R = Context.GetBuiltinType(ID, Error);
1987 if (!ForRedeclaration)
1990 // If we have a builtin without an associated type we should not emit a
1991 // warning when we were not able to find a type for it.
1992 if (Error == ASTContext::GE_Missing_type)
1995 // If we could not find a type for setjmp it is because the jmp_buf type was
1996 // not defined prior to the setjmp declaration.
1997 if (Error == ASTContext::GE_Missing_setjmp) {
1998 Diag(Loc, diag::warn_implicit_decl_no_jmp_buf)
1999 << Context.BuiltinInfo.getName(ID);
2003 // Generally, we emit a warning that the declaration requires the
2004 // appropriate header.
2005 Diag(Loc, diag::warn_implicit_decl_requires_sysheader)
2006 << getHeaderName(Context.BuiltinInfo, ID, Error)
2007 << Context.BuiltinInfo.getName(ID);
2011 if (!ForRedeclaration &&
2012 (Context.BuiltinInfo.isPredefinedLibFunction(ID) ||
2013 Context.BuiltinInfo.isHeaderDependentFunction(ID))) {
2014 Diag(Loc, diag::ext_implicit_lib_function_decl)
2015 << Context.BuiltinInfo.getName(ID) << R;
2016 if (Context.BuiltinInfo.getHeaderName(ID) &&
2017 !Diags.isIgnored(diag::ext_implicit_lib_function_decl, Loc))
2018 Diag(Loc, diag::note_include_header_or_declare)
2019 << Context.BuiltinInfo.getHeaderName(ID)
2020 << Context.BuiltinInfo.getName(ID);
2026 DeclContext *Parent = Context.getTranslationUnitDecl();
2027 if (getLangOpts().CPlusPlus) {
2028 LinkageSpecDecl *CLinkageDecl =
2029 LinkageSpecDecl::Create(Context, Parent, Loc, Loc,
2030 LinkageSpecDecl::lang_c, false);
2031 CLinkageDecl->setImplicit();
2032 Parent->addDecl(CLinkageDecl);
2033 Parent = CLinkageDecl;
2036 FunctionDecl *New = FunctionDecl::Create(Context,
2038 Loc, Loc, II, R, /*TInfo=*/nullptr,
2041 R->isFunctionProtoType());
2044 // Create Decl objects for each parameter, adding them to the
2046 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) {
2047 SmallVector<ParmVarDecl*, 16> Params;
2048 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
2050 ParmVarDecl::Create(Context, New, SourceLocation(), SourceLocation(),
2051 nullptr, FT->getParamType(i), /*TInfo=*/nullptr,
2053 parm->setScopeInfo(0, i);
2054 Params.push_back(parm);
2056 New->setParams(Params);
2059 AddKnownFunctionAttributes(New);
2060 RegisterLocallyScopedExternCDecl(New, S);
2062 // TUScope is the translation-unit scope to insert this function into.
2063 // FIXME: This is hideous. We need to teach PushOnScopeChains to
2064 // relate Scopes to DeclContexts, and probably eliminate CurContext
2065 // entirely, but we're not there yet.
2066 DeclContext *SavedContext = CurContext;
2067 CurContext = Parent;
2068 PushOnScopeChains(New, TUScope);
2069 CurContext = SavedContext;
2073 /// Typedef declarations don't have linkage, but they still denote the same
2074 /// entity if their types are the same.
2075 /// FIXME: This is notionally doing the same thing as ASTReaderDecl's
2077 static void filterNonConflictingPreviousTypedefDecls(Sema &S,
2078 TypedefNameDecl *Decl,
2079 LookupResult &Previous) {
2080 // This is only interesting when modules are enabled.
2081 if (!S.getLangOpts().Modules && !S.getLangOpts().ModulesLocalVisibility)
2084 // Empty sets are uninteresting.
2085 if (Previous.empty())
2088 LookupResult::Filter Filter = Previous.makeFilter();
2089 while (Filter.hasNext()) {
2090 NamedDecl *Old = Filter.next();
2092 // Non-hidden declarations are never ignored.
2093 if (S.isVisible(Old))
2096 // Declarations of the same entity are not ignored, even if they have
2097 // different linkages.
2098 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
2099 if (S.Context.hasSameType(OldTD->getUnderlyingType(),
2100 Decl->getUnderlyingType()))
2103 // If both declarations give a tag declaration a typedef name for linkage
2104 // purposes, then they declare the same entity.
2105 if (OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true) &&
2106 Decl->getAnonDeclWithTypedefName())
2116 bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) {
2118 if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old))
2119 OldType = OldTypedef->getUnderlyingType();
2121 OldType = Context.getTypeDeclType(Old);
2122 QualType NewType = New->getUnderlyingType();
2124 if (NewType->isVariablyModifiedType()) {
2125 // Must not redefine a typedef with a variably-modified type.
2126 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
2127 Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef)
2129 if (Old->getLocation().isValid())
2130 notePreviousDefinition(Old, New->getLocation());
2131 New->setInvalidDecl();
2135 if (OldType != NewType &&
2136 !OldType->isDependentType() &&
2137 !NewType->isDependentType() &&
2138 !Context.hasSameType(OldType, NewType)) {
2139 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
2140 Diag(New->getLocation(), diag::err_redefinition_different_typedef)
2141 << Kind << NewType << OldType;
2142 if (Old->getLocation().isValid())
2143 notePreviousDefinition(Old, New->getLocation());
2144 New->setInvalidDecl();
2150 /// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the
2151 /// same name and scope as a previous declaration 'Old'. Figure out
2152 /// how to resolve this situation, merging decls or emitting
2153 /// diagnostics as appropriate. If there was an error, set New to be invalid.
2155 void Sema::MergeTypedefNameDecl(Scope *S, TypedefNameDecl *New,
2156 LookupResult &OldDecls) {
2157 // If the new decl is known invalid already, don't bother doing any
2159 if (New->isInvalidDecl()) return;
2161 // Allow multiple definitions for ObjC built-in typedefs.
2162 // FIXME: Verify the underlying types are equivalent!
2163 if (getLangOpts().ObjC) {
2164 const IdentifierInfo *TypeID = New->getIdentifier();
2165 switch (TypeID->getLength()) {
2169 if (!TypeID->isStr("id"))
2171 QualType T = New->getUnderlyingType();
2172 if (!T->isPointerType())
2174 if (!T->isVoidPointerType()) {
2175 QualType PT = T->getAs<PointerType>()->getPointeeType();
2176 if (!PT->isStructureType())
2179 Context.setObjCIdRedefinitionType(T);
2180 // Install the built-in type for 'id', ignoring the current definition.
2181 New->setTypeForDecl(Context.getObjCIdType().getTypePtr());
2185 if (!TypeID->isStr("Class"))
2187 Context.setObjCClassRedefinitionType(New->getUnderlyingType());
2188 // Install the built-in type for 'Class', ignoring the current definition.
2189 New->setTypeForDecl(Context.getObjCClassType().getTypePtr());
2192 if (!TypeID->isStr("SEL"))
2194 Context.setObjCSelRedefinitionType(New->getUnderlyingType());
2195 // Install the built-in type for 'SEL', ignoring the current definition.
2196 New->setTypeForDecl(Context.getObjCSelType().getTypePtr());
2199 // Fall through - the typedef name was not a builtin type.
2202 // Verify the old decl was also a type.
2203 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>();
2205 Diag(New->getLocation(), diag::err_redefinition_different_kind)
2206 << New->getDeclName();
2208 NamedDecl *OldD = OldDecls.getRepresentativeDecl();
2209 if (OldD->getLocation().isValid())
2210 notePreviousDefinition(OldD, New->getLocation());
2212 return New->setInvalidDecl();
2215 // If the old declaration is invalid, just give up here.
2216 if (Old->isInvalidDecl())
2217 return New->setInvalidDecl();
2219 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
2220 auto *OldTag = OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true);
2221 auto *NewTag = New->getAnonDeclWithTypedefName();
2222 NamedDecl *Hidden = nullptr;
2223 if (OldTag && NewTag &&
2224 OldTag->getCanonicalDecl() != NewTag->getCanonicalDecl() &&
2225 !hasVisibleDefinition(OldTag, &Hidden)) {
2226 // There is a definition of this tag, but it is not visible. Use it
2227 // instead of our tag.
2228 New->setTypeForDecl(OldTD->getTypeForDecl());
2229 if (OldTD->isModed())
2230 New->setModedTypeSourceInfo(OldTD->getTypeSourceInfo(),
2231 OldTD->getUnderlyingType());
2233 New->setTypeSourceInfo(OldTD->getTypeSourceInfo());
2235 // Make the old tag definition visible.
2236 makeMergedDefinitionVisible(Hidden);
2238 // If this was an unscoped enumeration, yank all of its enumerators
2239 // out of the scope.
2240 if (isa<EnumDecl>(NewTag)) {
2241 Scope *EnumScope = getNonFieldDeclScope(S);
2242 for (auto *D : NewTag->decls()) {
2243 auto *ED = cast<EnumConstantDecl>(D);
2244 assert(EnumScope->isDeclScope(ED));
2245 EnumScope->RemoveDecl(ED);
2246 IdResolver.RemoveDecl(ED);
2247 ED->getLexicalDeclContext()->removeDecl(ED);
2253 // If the typedef types are not identical, reject them in all languages and
2254 // with any extensions enabled.
2255 if (isIncompatibleTypedef(Old, New))
2258 // The types match. Link up the redeclaration chain and merge attributes if
2259 // the old declaration was a typedef.
2260 if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) {
2261 New->setPreviousDecl(Typedef);
2262 mergeDeclAttributes(New, Old);
2265 if (getLangOpts().MicrosoftExt)
2268 if (getLangOpts().CPlusPlus) {
2269 // C++ [dcl.typedef]p2:
2270 // In a given non-class scope, a typedef specifier can be used to
2271 // redefine the name of any type declared in that scope to refer
2272 // to the type to which it already refers.
2273 if (!isa<CXXRecordDecl>(CurContext))
2276 // C++0x [dcl.typedef]p4:
2277 // In a given class scope, a typedef specifier can be used to redefine
2278 // any class-name declared in that scope that is not also a typedef-name
2279 // to refer to the type to which it already refers.
2281 // This wording came in via DR424, which was a correction to the
2282 // wording in DR56, which accidentally banned code like:
2285 // typedef struct A { } A;
2288 // in the C++03 standard. We implement the C++0x semantics, which
2289 // allow the above but disallow
2296 // since that was the intent of DR56.
2297 if (!isa<TypedefNameDecl>(Old))
2300 Diag(New->getLocation(), diag::err_redefinition)
2301 << New->getDeclName();
2302 notePreviousDefinition(Old, New->getLocation());
2303 return New->setInvalidDecl();
2306 // Modules always permit redefinition of typedefs, as does C11.
2307 if (getLangOpts().Modules || getLangOpts().C11)
2310 // If we have a redefinition of a typedef in C, emit a warning. This warning
2311 // is normally mapped to an error, but can be controlled with
2312 // -Wtypedef-redefinition. If either the original or the redefinition is
2313 // in a system header, don't emit this for compatibility with GCC.
2314 if (getDiagnostics().getSuppressSystemWarnings() &&
2315 // Some standard types are defined implicitly in Clang (e.g. OpenCL).
2316 (Old->isImplicit() ||
2317 Context.getSourceManager().isInSystemHeader(Old->getLocation()) ||
2318 Context.getSourceManager().isInSystemHeader(New->getLocation())))
2321 Diag(New->getLocation(), diag::ext_redefinition_of_typedef)
2322 << New->getDeclName();
2323 notePreviousDefinition(Old, New->getLocation());
2326 /// DeclhasAttr - returns true if decl Declaration already has the target
2328 static bool DeclHasAttr(const Decl *D, const Attr *A) {
2329 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A);
2330 const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A);
2331 for (const auto *i : D->attrs())
2332 if (i->getKind() == A->getKind()) {
2334 if (Ann->getAnnotation() == cast<AnnotateAttr>(i)->getAnnotation())
2338 // FIXME: Don't hardcode this check
2339 if (OA && isa<OwnershipAttr>(i))
2340 return OA->getOwnKind() == cast<OwnershipAttr>(i)->getOwnKind();
2347 static bool isAttributeTargetADefinition(Decl *D) {
2348 if (VarDecl *VD = dyn_cast<VarDecl>(D))
2349 return VD->isThisDeclarationADefinition();
2350 if (TagDecl *TD = dyn_cast<TagDecl>(D))
2351 return TD->isCompleteDefinition() || TD->isBeingDefined();
2355 /// Merge alignment attributes from \p Old to \p New, taking into account the
2356 /// special semantics of C11's _Alignas specifier and C++11's alignas attribute.
2358 /// \return \c true if any attributes were added to \p New.
2359 static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) {
2360 // Look for alignas attributes on Old, and pick out whichever attribute
2361 // specifies the strictest alignment requirement.
2362 AlignedAttr *OldAlignasAttr = nullptr;
2363 AlignedAttr *OldStrictestAlignAttr = nullptr;
2364 unsigned OldAlign = 0;
2365 for (auto *I : Old->specific_attrs<AlignedAttr>()) {
2366 // FIXME: We have no way of representing inherited dependent alignments
2368 // template<int A, int B> struct alignas(A) X;
2369 // template<int A, int B> struct alignas(B) X {};
2370 // For now, we just ignore any alignas attributes which are not on the
2371 // definition in such a case.
2372 if (I->isAlignmentDependent())
2378 unsigned Align = I->getAlignment(S.Context);
2379 if (Align > OldAlign) {
2381 OldStrictestAlignAttr = I;
2385 // Look for alignas attributes on New.
2386 AlignedAttr *NewAlignasAttr = nullptr;
2387 unsigned NewAlign = 0;
2388 for (auto *I : New->specific_attrs<AlignedAttr>()) {
2389 if (I->isAlignmentDependent())
2395 unsigned Align = I->getAlignment(S.Context);
2396 if (Align > NewAlign)
2400 if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) {
2401 // Both declarations have 'alignas' attributes. We require them to match.
2402 // C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but
2403 // fall short. (If two declarations both have alignas, they must both match
2404 // every definition, and so must match each other if there is a definition.)
2406 // If either declaration only contains 'alignas(0)' specifiers, then it
2407 // specifies the natural alignment for the type.
2408 if (OldAlign == 0 || NewAlign == 0) {
2410 if (ValueDecl *VD = dyn_cast<ValueDecl>(New))
2413 Ty = S.Context.getTagDeclType(cast<TagDecl>(New));
2416 OldAlign = S.Context.getTypeAlign(Ty);
2418 NewAlign = S.Context.getTypeAlign(Ty);
2421 if (OldAlign != NewAlign) {
2422 S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch)
2423 << (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity()
2424 << (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity();
2425 S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration);
2429 if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) {
2430 // C++11 [dcl.align]p6:
2431 // if any declaration of an entity has an alignment-specifier,
2432 // every defining declaration of that entity shall specify an
2433 // equivalent alignment.
2435 // If the definition of an object does not have an alignment
2436 // specifier, any other declaration of that object shall also
2437 // have no alignment specifier.
2438 S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition)
2440 S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration)
2444 bool AnyAdded = false;
2446 // Ensure we have an attribute representing the strictest alignment.
2447 if (OldAlign > NewAlign) {
2448 AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context);
2449 Clone->setInherited(true);
2450 New->addAttr(Clone);
2454 // Ensure we have an alignas attribute if the old declaration had one.
2455 if (OldAlignasAttr && !NewAlignasAttr &&
2456 !(AnyAdded && OldStrictestAlignAttr->isAlignas())) {
2457 AlignedAttr *Clone = OldAlignasAttr->clone(S.Context);
2458 Clone->setInherited(true);
2459 New->addAttr(Clone);
2466 static bool mergeDeclAttribute(Sema &S, NamedDecl *D,
2467 const InheritableAttr *Attr,
2468 Sema::AvailabilityMergeKind AMK) {
2469 // This function copies an attribute Attr from a previous declaration to the
2470 // new declaration D if the new declaration doesn't itself have that attribute
2471 // yet or if that attribute allows duplicates.
2472 // If you're adding a new attribute that requires logic different from
2473 // "use explicit attribute on decl if present, else use attribute from
2474 // previous decl", for example if the attribute needs to be consistent
2475 // between redeclarations, you need to call a custom merge function here.
2476 InheritableAttr *NewAttr = nullptr;
2477 unsigned AttrSpellingListIndex = Attr->getSpellingListIndex();
2478 if (const auto *AA = dyn_cast<AvailabilityAttr>(Attr))
2479 NewAttr = S.mergeAvailabilityAttr(
2480 D, AA->getRange(), AA->getPlatform(), AA->isImplicit(),
2481 AA->getIntroduced(), AA->getDeprecated(), AA->getObsoleted(),
2482 AA->getUnavailable(), AA->getMessage(), AA->getStrict(),
2483 AA->getReplacement(), AMK, AA->getPriority(), AttrSpellingListIndex);
2484 else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr))
2485 NewAttr = S.mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2486 AttrSpellingListIndex);
2487 else if (const auto *VA = dyn_cast<TypeVisibilityAttr>(Attr))
2488 NewAttr = S.mergeTypeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2489 AttrSpellingListIndex);
2490 else if (const auto *ImportA = dyn_cast<DLLImportAttr>(Attr))
2491 NewAttr = S.mergeDLLImportAttr(D, ImportA->getRange(),
2492 AttrSpellingListIndex);
2493 else if (const auto *ExportA = dyn_cast<DLLExportAttr>(Attr))
2494 NewAttr = S.mergeDLLExportAttr(D, ExportA->getRange(),
2495 AttrSpellingListIndex);
2496 else if (const auto *FA = dyn_cast<FormatAttr>(Attr))
2497 NewAttr = S.mergeFormatAttr(D, FA->getRange(), FA->getType(),
2498 FA->getFormatIdx(), FA->getFirstArg(),
2499 AttrSpellingListIndex);
2500 else if (const auto *SA = dyn_cast<SectionAttr>(Attr))
2501 NewAttr = S.mergeSectionAttr(D, SA->getRange(), SA->getName(),
2502 AttrSpellingListIndex);
2503 else if (const auto *CSA = dyn_cast<CodeSegAttr>(Attr))
2504 NewAttr = S.mergeCodeSegAttr(D, CSA->getRange(), CSA->getName(),
2505 AttrSpellingListIndex);
2506 else if (const auto *IA = dyn_cast<MSInheritanceAttr>(Attr))
2507 NewAttr = S.mergeMSInheritanceAttr(D, IA->getRange(), IA->getBestCase(),
2508 AttrSpellingListIndex,
2509 IA->getSemanticSpelling());
2510 else if (const auto *AA = dyn_cast<AlwaysInlineAttr>(Attr))
2511 NewAttr = S.mergeAlwaysInlineAttr(D, AA->getRange(),
2512 &S.Context.Idents.get(AA->getSpelling()),
2513 AttrSpellingListIndex);
2514 else if (S.getLangOpts().CUDA && isa<FunctionDecl>(D) &&
2515 (isa<CUDAHostAttr>(Attr) || isa<CUDADeviceAttr>(Attr) ||
2516 isa<CUDAGlobalAttr>(Attr))) {
2517 // CUDA target attributes are part of function signature for
2518 // overloading purposes and must not be merged.
2520 } else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr))
2521 NewAttr = S.mergeMinSizeAttr(D, MA->getRange(), AttrSpellingListIndex);
2522 else if (const auto *OA = dyn_cast<OptimizeNoneAttr>(Attr))
2523 NewAttr = S.mergeOptimizeNoneAttr(D, OA->getRange(), AttrSpellingListIndex);
2524 else if (const auto *InternalLinkageA = dyn_cast<InternalLinkageAttr>(Attr))
2525 NewAttr = S.mergeInternalLinkageAttr(D, *InternalLinkageA);
2526 else if (const auto *CommonA = dyn_cast<CommonAttr>(Attr))
2527 NewAttr = S.mergeCommonAttr(D, *CommonA);
2528 else if (isa<AlignedAttr>(Attr))
2529 // AlignedAttrs are handled separately, because we need to handle all
2530 // such attributes on a declaration at the same time.
2532 else if ((isa<DeprecatedAttr>(Attr) || isa<UnavailableAttr>(Attr)) &&
2533 (AMK == Sema::AMK_Override ||
2534 AMK == Sema::AMK_ProtocolImplementation))
2536 else if (const auto *UA = dyn_cast<UuidAttr>(Attr))
2537 NewAttr = S.mergeUuidAttr(D, UA->getRange(), AttrSpellingListIndex,
2539 else if (const auto *SLHA = dyn_cast<SpeculativeLoadHardeningAttr>(Attr))
2540 NewAttr = S.mergeSpeculativeLoadHardeningAttr(D, *SLHA);
2541 else if (const auto *SLHA = dyn_cast<NoSpeculativeLoadHardeningAttr>(Attr))
2542 NewAttr = S.mergeNoSpeculativeLoadHardeningAttr(D, *SLHA);
2543 else if (Attr->shouldInheritEvenIfAlreadyPresent() || !DeclHasAttr(D, Attr))
2544 NewAttr = cast<InheritableAttr>(Attr->clone(S.Context));
2547 NewAttr->setInherited(true);
2548 D->addAttr(NewAttr);
2549 if (isa<MSInheritanceAttr>(NewAttr))
2550 S.Consumer.AssignInheritanceModel(cast<CXXRecordDecl>(D));
2557 static const NamedDecl *getDefinition(const Decl *D) {
2558 if (const TagDecl *TD = dyn_cast<TagDecl>(D))
2559 return TD->getDefinition();
2560 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
2561 const VarDecl *Def = VD->getDefinition();
2564 return VD->getActingDefinition();
2566 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
2567 return FD->getDefinition();
2571 static bool hasAttribute(const Decl *D, attr::Kind Kind) {
2572 for (const auto *Attribute : D->attrs())
2573 if (Attribute->getKind() == Kind)
2578 /// checkNewAttributesAfterDef - If we already have a definition, check that
2579 /// there are no new attributes in this declaration.
2580 static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) {
2581 if (!New->hasAttrs())
2584 const NamedDecl *Def = getDefinition(Old);
2585 if (!Def || Def == New)
2588 AttrVec &NewAttributes = New->getAttrs();
2589 for (unsigned I = 0, E = NewAttributes.size(); I != E;) {
2590 const Attr *NewAttribute = NewAttributes[I];
2592 if (isa<AliasAttr>(NewAttribute) || isa<IFuncAttr>(NewAttribute)) {
2593 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(New)) {
2594 Sema::SkipBodyInfo SkipBody;
2595 S.CheckForFunctionRedefinition(FD, cast<FunctionDecl>(Def), &SkipBody);
2597 // If we're skipping this definition, drop the "alias" attribute.
2598 if (SkipBody.ShouldSkip) {
2599 NewAttributes.erase(NewAttributes.begin() + I);
2604 VarDecl *VD = cast<VarDecl>(New);
2605 unsigned Diag = cast<VarDecl>(Def)->isThisDeclarationADefinition() ==
2606 VarDecl::TentativeDefinition
2607 ? diag::err_alias_after_tentative
2608 : diag::err_redefinition;
2609 S.Diag(VD->getLocation(), Diag) << VD->getDeclName();
2610 if (Diag == diag::err_redefinition)
2611 S.notePreviousDefinition(Def, VD->getLocation());
2613 S.Diag(Def->getLocation(), diag::note_previous_definition);
2614 VD->setInvalidDecl();
2620 if (const VarDecl *VD = dyn_cast<VarDecl>(Def)) {
2621 // Tentative definitions are only interesting for the alias check above.
2622 if (VD->isThisDeclarationADefinition() != VarDecl::Definition) {
2628 if (hasAttribute(Def, NewAttribute->getKind())) {
2630 continue; // regular attr merging will take care of validating this.
2633 if (isa<C11NoReturnAttr>(NewAttribute)) {
2634 // C's _Noreturn is allowed to be added to a function after it is defined.
2637 } else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) {
2638 if (AA->isAlignas()) {
2639 // C++11 [dcl.align]p6:
2640 // if any declaration of an entity has an alignment-specifier,
2641 // every defining declaration of that entity shall specify an
2642 // equivalent alignment.
2644 // If the definition of an object does not have an alignment
2645 // specifier, any other declaration of that object shall also
2646 // have no alignment specifier.
2647 S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition)
2649 S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration)
2651 NewAttributes.erase(NewAttributes.begin() + I);
2657 S.Diag(NewAttribute->getLocation(),
2658 diag::warn_attribute_precede_definition);
2659 S.Diag(Def->getLocation(), diag::note_previous_definition);
2660 NewAttributes.erase(NewAttributes.begin() + I);
2665 /// mergeDeclAttributes - Copy attributes from the Old decl to the New one.
2666 void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old,
2667 AvailabilityMergeKind AMK) {
2668 if (UsedAttr *OldAttr = Old->getMostRecentDecl()->getAttr<UsedAttr>()) {
2669 UsedAttr *NewAttr = OldAttr->clone(Context);
2670 NewAttr->setInherited(true);
2671 New->addAttr(NewAttr);
2674 if (!Old->hasAttrs() && !New->hasAttrs())
2677 // Attributes declared post-definition are currently ignored.
2678 checkNewAttributesAfterDef(*this, New, Old);
2680 if (AsmLabelAttr *NewA = New->getAttr<AsmLabelAttr>()) {
2681 if (AsmLabelAttr *OldA = Old->getAttr<AsmLabelAttr>()) {
2682 if (OldA->getLabel() != NewA->getLabel()) {
2683 // This redeclaration changes __asm__ label.
2684 Diag(New->getLocation(), diag::err_different_asm_label);
2685 Diag(OldA->getLocation(), diag::note_previous_declaration);
2687 } else if (Old->isUsed()) {
2688 // This redeclaration adds an __asm__ label to a declaration that has
2689 // already been ODR-used.
2690 Diag(New->getLocation(), diag::err_late_asm_label_name)
2691 << isa<FunctionDecl>(Old) << New->getAttr<AsmLabelAttr>()->getRange();
2695 // Re-declaration cannot add abi_tag's.
2696 if (const auto *NewAbiTagAttr = New->getAttr<AbiTagAttr>()) {
2697 if (const auto *OldAbiTagAttr = Old->getAttr<AbiTagAttr>()) {
2698 for (const auto &NewTag : NewAbiTagAttr->tags()) {
2699 if (std::find(OldAbiTagAttr->tags_begin(), OldAbiTagAttr->tags_end(),
2700 NewTag) == OldAbiTagAttr->tags_end()) {
2701 Diag(NewAbiTagAttr->getLocation(),
2702 diag::err_new_abi_tag_on_redeclaration)
2704 Diag(OldAbiTagAttr->getLocation(), diag::note_previous_declaration);
2708 Diag(NewAbiTagAttr->getLocation(), diag::err_abi_tag_on_redeclaration);
2709 Diag(Old->getLocation(), diag::note_previous_declaration);
2713 // This redeclaration adds a section attribute.
2714 if (New->hasAttr<SectionAttr>() && !Old->hasAttr<SectionAttr>()) {
2715 if (auto *VD = dyn_cast<VarDecl>(New)) {
2716 if (VD->isThisDeclarationADefinition() == VarDecl::DeclarationOnly) {
2717 Diag(New->getLocation(), diag::warn_attribute_section_on_redeclaration);
2718 Diag(Old->getLocation(), diag::note_previous_declaration);
2723 // Redeclaration adds code-seg attribute.
2724 const auto *NewCSA = New->getAttr<CodeSegAttr>();
2725 if (NewCSA && !Old->hasAttr<CodeSegAttr>() &&
2726 !NewCSA->isImplicit() && isa<CXXMethodDecl>(New)) {
2727 Diag(New->getLocation(), diag::warn_mismatched_section)
2729 Diag(Old->getLocation(), diag::note_previous_declaration);
2732 if (!Old->hasAttrs())
2735 bool foundAny = New->hasAttrs();
2737 // Ensure that any moving of objects within the allocated map is done before
2739 if (!foundAny) New->setAttrs(AttrVec());
2741 for (auto *I : Old->specific_attrs<InheritableAttr>()) {
2742 // Ignore deprecated/unavailable/availability attributes if requested.
2743 AvailabilityMergeKind LocalAMK = AMK_None;
2744 if (isa<DeprecatedAttr>(I) ||
2745 isa<UnavailableAttr>(I) ||
2746 isa<AvailabilityAttr>(I)) {
2751 case AMK_Redeclaration:
2753 case AMK_ProtocolImplementation:
2760 if (isa<UsedAttr>(I))
2763 if (mergeDeclAttribute(*this, New, I, LocalAMK))
2767 if (mergeAlignedAttrs(*this, New, Old))
2770 if (!foundAny) New->dropAttrs();
2773 /// mergeParamDeclAttributes - Copy attributes from the old parameter
2775 static void mergeParamDeclAttributes(ParmVarDecl *newDecl,
2776 const ParmVarDecl *oldDecl,
2778 // C++11 [dcl.attr.depend]p2:
2779 // The first declaration of a function shall specify the
2780 // carries_dependency attribute for its declarator-id if any declaration
2781 // of the function specifies the carries_dependency attribute.
2782 const CarriesDependencyAttr *CDA = newDecl->getAttr<CarriesDependencyAttr>();
2783 if (CDA && !oldDecl->hasAttr<CarriesDependencyAttr>()) {
2784 S.Diag(CDA->getLocation(),
2785 diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/;
2786 // Find the first declaration of the parameter.
2787 // FIXME: Should we build redeclaration chains for function parameters?
2788 const FunctionDecl *FirstFD =
2789 cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDecl();
2790 const ParmVarDecl *FirstVD =
2791 FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex());
2792 S.Diag(FirstVD->getLocation(),
2793 diag::note_carries_dependency_missing_first_decl) << 1/*Param*/;
2796 if (!oldDecl->hasAttrs())
2799 bool foundAny = newDecl->hasAttrs();
2801 // Ensure that any moving of objects within the allocated map is
2802 // done before we process them.
2803 if (!foundAny) newDecl->setAttrs(AttrVec());
2805 for (const auto *I : oldDecl->specific_attrs<InheritableParamAttr>()) {
2806 if (!DeclHasAttr(newDecl, I)) {
2807 InheritableAttr *newAttr =
2808 cast<InheritableParamAttr>(I->clone(S.Context));
2809 newAttr->setInherited(true);
2810 newDecl->addAttr(newAttr);
2815 if (!foundAny) newDecl->dropAttrs();
2818 static void mergeParamDeclTypes(ParmVarDecl *NewParam,
2819 const ParmVarDecl *OldParam,
2821 if (auto Oldnullability = OldParam->getType()->getNullability(S.Context)) {
2822 if (auto Newnullability = NewParam->getType()->getNullability(S.Context)) {
2823 if (*Oldnullability != *Newnullability) {
2824 S.Diag(NewParam->getLocation(), diag::warn_mismatched_nullability_attr)
2825 << DiagNullabilityKind(
2827 ((NewParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2829 << DiagNullabilityKind(
2831 ((OldParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2833 S.Diag(OldParam->getLocation(), diag::note_previous_declaration);
2836 QualType NewT = NewParam->getType();
2837 NewT = S.Context.getAttributedType(
2838 AttributedType::getNullabilityAttrKind(*Oldnullability),
2840 NewParam->setType(NewT);
2847 /// Used in MergeFunctionDecl to keep track of function parameters in
2849 struct GNUCompatibleParamWarning {
2850 ParmVarDecl *OldParm;
2851 ParmVarDecl *NewParm;
2852 QualType PromotedType;
2855 } // end anonymous namespace
2857 /// getSpecialMember - get the special member enum for a method.
2858 Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) {
2859 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
2860 if (Ctor->isDefaultConstructor())
2861 return Sema::CXXDefaultConstructor;
2863 if (Ctor->isCopyConstructor())
2864 return Sema::CXXCopyConstructor;
2866 if (Ctor->isMoveConstructor())
2867 return Sema::CXXMoveConstructor;
2868 } else if (isa<CXXDestructorDecl>(MD)) {
2869 return Sema::CXXDestructor;
2870 } else if (MD->isCopyAssignmentOperator()) {
2871 return Sema::CXXCopyAssignment;
2872 } else if (MD->isMoveAssignmentOperator()) {
2873 return Sema::CXXMoveAssignment;
2876 return Sema::CXXInvalid;
2879 // Determine whether the previous declaration was a definition, implicit
2880 // declaration, or a declaration.
2881 template <typename T>
2882 static std::pair<diag::kind, SourceLocation>
2883 getNoteDiagForInvalidRedeclaration(const T *Old, const T *New) {
2884 diag::kind PrevDiag;
2885 SourceLocation OldLocation = Old->getLocation();
2886 if (Old->isThisDeclarationADefinition())
2887 PrevDiag = diag::note_previous_definition;
2888 else if (Old->isImplicit()) {
2889 PrevDiag = diag::note_previous_implicit_declaration;
2890 if (OldLocation.isInvalid())
2891 OldLocation = New->getLocation();
2893 PrevDiag = diag::note_previous_declaration;
2894 return std::make_pair(PrevDiag, OldLocation);
2897 /// canRedefineFunction - checks if a function can be redefined. Currently,
2898 /// only extern inline functions can be redefined, and even then only in
2900 static bool canRedefineFunction(const FunctionDecl *FD,
2901 const LangOptions& LangOpts) {
2902 return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) &&
2903 !LangOpts.CPlusPlus &&
2904 FD->isInlineSpecified() &&
2905 FD->getStorageClass() == SC_Extern);
2908 const AttributedType *Sema::getCallingConvAttributedType(QualType T) const {
2909 const AttributedType *AT = T->getAs<AttributedType>();
2910 while (AT && !AT->isCallingConv())
2911 AT = AT->getModifiedType()->getAs<AttributedType>();
2915 template <typename T>
2916 static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) {
2917 const DeclContext *DC = Old->getDeclContext();
2921 LanguageLinkage OldLinkage = Old->getLanguageLinkage();
2922 if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext())
2924 if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext())
2929 template<typename T> static bool isExternC(T *D) { return D->isExternC(); }
2930 static bool isExternC(VarTemplateDecl *) { return false; }
2932 /// Check whether a redeclaration of an entity introduced by a
2933 /// using-declaration is valid, given that we know it's not an overload
2934 /// (nor a hidden tag declaration).
2935 template<typename ExpectedDecl>
2936 static bool checkUsingShadowRedecl(Sema &S, UsingShadowDecl *OldS,
2937 ExpectedDecl *New) {
2938 // C++11 [basic.scope.declarative]p4:
2939 // Given a set of declarations in a single declarative region, each of
2940 // which specifies the same unqualified name,
2941 // -- they shall all refer to the same entity, or all refer to functions
2942 // and function templates; or
2943 // -- exactly one declaration shall declare a class name or enumeration
2944 // name that is not a typedef name and the other declarations shall all
2945 // refer to the same variable or enumerator, or all refer to functions
2946 // and function templates; in this case the class name or enumeration
2947 // name is hidden (3.3.10).
2949 // C++11 [namespace.udecl]p14:
2950 // If a function declaration in namespace scope or block scope has the
2951 // same name and the same parameter-type-list as a function introduced
2952 // by a using-declaration, and the declarations do not declare the same
2953 // function, the program is ill-formed.
2955 auto *Old = dyn_cast<ExpectedDecl>(OldS->getTargetDecl());
2957 !Old->getDeclContext()->getRedeclContext()->Equals(
2958 New->getDeclContext()->getRedeclContext()) &&
2959 !(isExternC(Old) && isExternC(New)))
2963 S.Diag(New->getLocation(), diag::err_using_decl_conflict_reverse);
2964 S.Diag(OldS->getTargetDecl()->getLocation(), diag::note_using_decl_target);
2965 S.Diag(OldS->getUsingDecl()->getLocation(), diag::note_using_decl) << 0;
2971 static bool hasIdenticalPassObjectSizeAttrs(const FunctionDecl *A,
2972 const FunctionDecl *B) {
2973 assert(A->getNumParams() == B->getNumParams());
2975 auto AttrEq = [](const ParmVarDecl *A, const ParmVarDecl *B) {
2976 const auto *AttrA = A->getAttr<PassObjectSizeAttr>();
2977 const auto *AttrB = B->getAttr<PassObjectSizeAttr>();
2980 return AttrA && AttrB && AttrA->getType() == AttrB->getType() &&
2981 AttrA->isDynamic() == AttrB->isDynamic();
2984 return std::equal(A->param_begin(), A->param_end(), B->param_begin(), AttrEq);
2987 /// If necessary, adjust the semantic declaration context for a qualified
2988 /// declaration to name the correct inline namespace within the qualifier.
2989 static void adjustDeclContextForDeclaratorDecl(DeclaratorDecl *NewD,
2990 DeclaratorDecl *OldD) {
2991 // The only case where we need to update the DeclContext is when
2992 // redeclaration lookup for a qualified name finds a declaration
2993 // in an inline namespace within the context named by the qualifier:
2995 // inline namespace N { int f(); }
2996 // int ::f(); // Sema DC needs adjusting from :: to N::.
2998 // For unqualified declarations, the semantic context *can* change
2999 // along the redeclaration chain (for local extern declarations,
3000 // extern "C" declarations, and friend declarations in particular).
3001 if (!NewD->getQualifier())
3004 // NewD is probably already in the right context.
3005 auto *NamedDC = NewD->getDeclContext()->getRedeclContext();
3006 auto *SemaDC = OldD->getDeclContext()->getRedeclContext();
3007 if (NamedDC->Equals(SemaDC))
3010 assert((NamedDC->InEnclosingNamespaceSetOf(SemaDC) ||
3011 NewD->isInvalidDecl() || OldD->isInvalidDecl()) &&
3012 "unexpected context for redeclaration");
3014 auto *LexDC = NewD->getLexicalDeclContext();
3015 auto FixSemaDC = [=](NamedDecl *D) {
3018 D->setDeclContext(SemaDC);
3019 D->setLexicalDeclContext(LexDC);
3023 if (auto *FD = dyn_cast<FunctionDecl>(NewD))
3024 FixSemaDC(FD->getDescribedFunctionTemplate());
3025 else if (auto *VD = dyn_cast<VarDecl>(NewD))
3026 FixSemaDC(VD->getDescribedVarTemplate());
3029 /// MergeFunctionDecl - We just parsed a function 'New' from
3030 /// declarator D which has the same name and scope as a previous
3031 /// declaration 'Old'. Figure out how to resolve this situation,
3032 /// merging decls or emitting diagnostics as appropriate.
3034 /// In C++, New and Old must be declarations that are not
3035 /// overloaded. Use IsOverload to determine whether New and Old are
3036 /// overloaded, and to select the Old declaration that New should be
3039 /// Returns true if there was an error, false otherwise.
3040 bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
3041 Scope *S, bool MergeTypeWithOld) {
3042 // Verify the old decl was also a function.
3043 FunctionDecl *Old = OldD->getAsFunction();
3045 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) {
3046 if (New->getFriendObjectKind()) {
3047 Diag(New->getLocation(), diag::err_using_decl_friend);
3048 Diag(Shadow->getTargetDecl()->getLocation(),
3049 diag::note_using_decl_target);
3050 Diag(Shadow->getUsingDecl()->getLocation(),
3051 diag::note_using_decl) << 0;
3055 // Check whether the two declarations might declare the same function.
3056 if (checkUsingShadowRedecl<FunctionDecl>(*this, Shadow, New))
3058 OldD = Old = cast<FunctionDecl>(Shadow->getTargetDecl());
3060 Diag(New->getLocation(), diag::err_redefinition_different_kind)
3061 << New->getDeclName();
3062 notePreviousDefinition(OldD, New->getLocation());
3067 // If the old declaration is invalid, just give up here.
3068 if (Old->isInvalidDecl())
3071 // Disallow redeclaration of some builtins.
3072 if (!getASTContext().canBuiltinBeRedeclared(Old)) {
3073 Diag(New->getLocation(), diag::err_builtin_redeclare) << Old->getDeclName();
3074 Diag(Old->getLocation(), diag::note_previous_builtin_declaration)
3075 << Old << Old->getType();
3079 diag::kind PrevDiag;
3080 SourceLocation OldLocation;
3081 std::tie(PrevDiag, OldLocation) =
3082 getNoteDiagForInvalidRedeclaration(Old, New);
3084 // Don't complain about this if we're in GNU89 mode and the old function
3085 // is an extern inline function.
3086 // Don't complain about specializations. They are not supposed to have
3088 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) &&
3089 New->getStorageClass() == SC_Static &&
3090 Old->hasExternalFormalLinkage() &&
3091 !New->getTemplateSpecializationInfo() &&
3092 !canRedefineFunction(Old, getLangOpts())) {
3093 if (getLangOpts().MicrosoftExt) {
3094 Diag(New->getLocation(), diag::ext_static_non_static) << New;
3095 Diag(OldLocation, PrevDiag);
3097 Diag(New->getLocation(), diag::err_static_non_static) << New;
3098 Diag(OldLocation, PrevDiag);
3103 if (New->hasAttr<InternalLinkageAttr>() &&
3104 !Old->hasAttr<InternalLinkageAttr>()) {
3105 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
3106 << New->getDeclName();
3107 notePreviousDefinition(Old, New->getLocation());
3108 New->dropAttr<InternalLinkageAttr>();
3111 if (CheckRedeclarationModuleOwnership(New, Old))
3114 if (!getLangOpts().CPlusPlus) {
3115 bool OldOvl = Old->hasAttr<OverloadableAttr>();
3116 if (OldOvl != New->hasAttr<OverloadableAttr>() && !Old->isImplicit()) {
3117 Diag(New->getLocation(), diag::err_attribute_overloadable_mismatch)
3120 // Try our best to find a decl that actually has the overloadable
3121 // attribute for the note. In most cases (e.g. programs with only one
3122 // broken declaration/definition), this won't matter.
3124 // FIXME: We could do this if we juggled some extra state in
3125 // OverloadableAttr, rather than just removing it.
3126 const Decl *DiagOld = Old;
3128 auto OldIter = llvm::find_if(Old->redecls(), [](const Decl *D) {
3129 const auto *A = D->getAttr<OverloadableAttr>();
3130 return A && !A->isImplicit();
3132 // If we've implicitly added *all* of the overloadable attrs to this
3133 // chain, emitting a "previous redecl" note is pointless.
3134 DiagOld = OldIter == Old->redecls_end() ? nullptr : *OldIter;
3138 Diag(DiagOld->getLocation(),
3139 diag::note_attribute_overloadable_prev_overload)
3143 New->addAttr(OverloadableAttr::CreateImplicit(Context));
3145 New->dropAttr<OverloadableAttr>();
3149 // If a function is first declared with a calling convention, but is later
3150 // declared or defined without one, all following decls assume the calling
3151 // convention of the first.
3153 // It's OK if a function is first declared without a calling convention,
3154 // but is later declared or defined with the default calling convention.
3156 // To test if either decl has an explicit calling convention, we look for
3157 // AttributedType sugar nodes on the type as written. If they are missing or
3158 // were canonicalized away, we assume the calling convention was implicit.
3160 // Note also that we DO NOT return at this point, because we still have
3161 // other tests to run.
3162 QualType OldQType = Context.getCanonicalType(Old->getType());
3163 QualType NewQType = Context.getCanonicalType(New->getType());
3164 const FunctionType *OldType = cast<FunctionType>(OldQType);
3165 const FunctionType *NewType = cast<FunctionType>(NewQType);
3166 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo();
3167 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo();
3168 bool RequiresAdjustment = false;
3170 if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) {
3171 FunctionDecl *First = Old->getFirstDecl();
3172 const FunctionType *FT =
3173 First->getType().getCanonicalType()->castAs<FunctionType>();
3174 FunctionType::ExtInfo FI = FT->getExtInfo();
3175 bool NewCCExplicit = getCallingConvAttributedType(New->getType());
3176 if (!NewCCExplicit) {
3177 // Inherit the CC from the previous declaration if it was specified
3178 // there but not here.
3179 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
3180 RequiresAdjustment = true;
3181 } else if (New->getBuiltinID()) {
3182 // Calling Conventions on a Builtin aren't really useful and setting a
3183 // default calling convention and cdecl'ing some builtin redeclarations is
3184 // common, so warn and ignore the calling convention on the redeclaration.
3185 Diag(New->getLocation(), diag::warn_cconv_unsupported)
3186 << FunctionType::getNameForCallConv(NewTypeInfo.getCC())
3187 << (int)CallingConventionIgnoredReason::BuiltinFunction;
3188 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
3189 RequiresAdjustment = true;
3191 // Calling conventions aren't compatible, so complain.
3192 bool FirstCCExplicit = getCallingConvAttributedType(First->getType());
3193 Diag(New->getLocation(), diag::err_cconv_change)
3194 << FunctionType::getNameForCallConv(NewTypeInfo.getCC())
3196 << (!FirstCCExplicit ? "" :
3197 FunctionType::getNameForCallConv(FI.getCC()));
3199 // Put the note on the first decl, since it is the one that matters.
3200 Diag(First->getLocation(), diag::note_previous_declaration);
3205 // FIXME: diagnose the other way around?
3206 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) {
3207 NewTypeInfo = NewTypeInfo.withNoReturn(true);
3208 RequiresAdjustment = true;
3211 // Merge regparm attribute.
3212 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() ||
3213 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) {
3214 if (NewTypeInfo.getHasRegParm()) {
3215 Diag(New->getLocation(), diag::err_regparm_mismatch)
3216 << NewType->getRegParmType()
3217 << OldType->getRegParmType();
3218 Diag(OldLocation, diag::note_previous_declaration);
3222 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm());
3223 RequiresAdjustment = true;
3226 // Merge ns_returns_retained attribute.
3227 if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) {
3228 if (NewTypeInfo.getProducesResult()) {
3229 Diag(New->getLocation(), diag::err_function_attribute_mismatch)
3230 << "'ns_returns_retained'";
3231 Diag(OldLocation, diag::note_previous_declaration);
3235 NewTypeInfo = NewTypeInfo.withProducesResult(true);
3236 RequiresAdjustment = true;
3239 if (OldTypeInfo.getNoCallerSavedRegs() !=
3240 NewTypeInfo.getNoCallerSavedRegs()) {
3241 if (NewTypeInfo.getNoCallerSavedRegs()) {
3242 AnyX86NoCallerSavedRegistersAttr *Attr =
3243 New->getAttr<AnyX86NoCallerSavedRegistersAttr>();
3244 Diag(New->getLocation(), diag::err_function_attribute_mismatch) << Attr;
3245 Diag(OldLocation, diag::note_previous_declaration);
3249 NewTypeInfo = NewTypeInfo.withNoCallerSavedRegs(true);
3250 RequiresAdjustment = true;
3253 if (RequiresAdjustment) {
3254 const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>();
3255 AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo);
3256 New->setType(QualType(AdjustedType, 0));
3257 NewQType = Context.getCanonicalType(New->getType());
3260 // If this redeclaration makes the function inline, we may need to add it to
3261 // UndefinedButUsed.
3262 if (!Old->isInlined() && New->isInlined() &&
3263 !New->hasAttr<GNUInlineAttr>() &&
3264 !getLangOpts().GNUInline &&
3265 Old->isUsed(false) &&
3266 !Old->isDefined() && !New->isThisDeclarationADefinition())
3267 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
3270 // If this redeclaration makes it newly gnu_inline, we don't want to warn
3272 if (New->hasAttr<GNUInlineAttr>() &&
3273 Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) {
3274 UndefinedButUsed.erase(Old->getCanonicalDecl());
3277 // If pass_object_size params don't match up perfectly, this isn't a valid
3279 if (Old->getNumParams() > 0 && Old->getNumParams() == New->getNumParams() &&
3280 !hasIdenticalPassObjectSizeAttrs(Old, New)) {
3281 Diag(New->getLocation(), diag::err_different_pass_object_size_params)
3282 << New->getDeclName();
3283 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3287 if (getLangOpts().CPlusPlus) {
3288 // C++1z [over.load]p2
3289 // Certain function declarations cannot be overloaded:
3290 // -- Function declarations that differ only in the return type,
3291 // the exception specification, or both cannot be overloaded.
3293 // Check the exception specifications match. This may recompute the type of
3294 // both Old and New if it resolved exception specifications, so grab the
3295 // types again after this. Because this updates the type, we do this before
3296 // any of the other checks below, which may update the "de facto" NewQType
3297 // but do not necessarily update the type of New.
3298 if (CheckEquivalentExceptionSpec(Old, New))
3300 OldQType = Context.getCanonicalType(Old->getType());
3301 NewQType = Context.getCanonicalType(New->getType());
3303 // Go back to the type source info to compare the declared return types,
3304 // per C++1y [dcl.type.auto]p13:
3305 // Redeclarations or specializations of a function or function template
3306 // with a declared return type that uses a placeholder type shall also
3307 // use that placeholder, not a deduced type.
3308 QualType OldDeclaredReturnType = Old->getDeclaredReturnType();
3309 QualType NewDeclaredReturnType = New->getDeclaredReturnType();
3310 if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType) &&
3311 canFullyTypeCheckRedeclaration(New, Old, NewDeclaredReturnType,
3312 OldDeclaredReturnType)) {
3314 if (NewDeclaredReturnType->isObjCObjectPointerType() &&
3315 OldDeclaredReturnType->isObjCObjectPointerType())
3316 // FIXME: This does the wrong thing for a deduced return type.
3317 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType);
3318 if (ResQT.isNull()) {
3319 if (New->isCXXClassMember() && New->isOutOfLine())
3320 Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type)
3321 << New << New->getReturnTypeSourceRange();
3323 Diag(New->getLocation(), diag::err_ovl_diff_return_type)
3324 << New->getReturnTypeSourceRange();
3325 Diag(OldLocation, PrevDiag) << Old << Old->getType()
3326 << Old->getReturnTypeSourceRange();
3333 QualType OldReturnType = OldType->getReturnType();
3334 QualType NewReturnType = cast<FunctionType>(NewQType)->getReturnType();
3335 if (OldReturnType != NewReturnType) {
3336 // If this function has a deduced return type and has already been
3337 // defined, copy the deduced value from the old declaration.
3338 AutoType *OldAT = Old->getReturnType()->getContainedAutoType();
3339 if (OldAT && OldAT->isDeduced()) {
3341 SubstAutoType(New->getType(),
3342 OldAT->isDependentType() ? Context.DependentTy
3343 : OldAT->getDeducedType()));
3344 NewQType = Context.getCanonicalType(
3345 SubstAutoType(NewQType,
3346 OldAT->isDependentType() ? Context.DependentTy
3347 : OldAT->getDeducedType()));
3351 const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
3352 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
3353 if (OldMethod && NewMethod) {
3354 // Preserve triviality.
3355 NewMethod->setTrivial(OldMethod->isTrivial());
3357 // MSVC allows explicit template specialization at class scope:
3358 // 2 CXXMethodDecls referring to the same function will be injected.
3359 // We don't want a redeclaration error.
3360 bool IsClassScopeExplicitSpecialization =
3361 OldMethod->isFunctionTemplateSpecialization() &&
3362 NewMethod->isFunctionTemplateSpecialization();
3363 bool isFriend = NewMethod->getFriendObjectKind();
3365 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() &&
3366 !IsClassScopeExplicitSpecialization) {
3367 // -- Member function declarations with the same name and the
3368 // same parameter types cannot be overloaded if any of them
3369 // is a static member function declaration.
3370 if (OldMethod->isStatic() != NewMethod->isStatic()) {
3371 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
3372 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3376 // C++ [class.mem]p1:
3377 // [...] A member shall not be declared twice in the
3378 // member-specification, except that a nested class or member
3379 // class template can be declared and then later defined.
3380 if (!inTemplateInstantiation()) {
3382 if (isa<CXXConstructorDecl>(OldMethod))
3383 NewDiag = diag::err_constructor_redeclared;
3384 else if (isa<CXXDestructorDecl>(NewMethod))
3385 NewDiag = diag::err_destructor_redeclared;
3386 else if (isa<CXXConversionDecl>(NewMethod))
3387 NewDiag = diag::err_conv_function_redeclared;
3389 NewDiag = diag::err_member_redeclared;
3391 Diag(New->getLocation(), NewDiag);
3393 Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation)
3394 << New << New->getType();
3396 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3399 // Complain if this is an explicit declaration of a special
3400 // member that was initially declared implicitly.
3402 // As an exception, it's okay to befriend such methods in order
3403 // to permit the implicit constructor/destructor/operator calls.
3404 } else if (OldMethod->isImplicit()) {
3406 NewMethod->setImplicit();
3408 Diag(NewMethod->getLocation(),
3409 diag::err_definition_of_implicitly_declared_member)
3410 << New << getSpecialMember(OldMethod);
3413 } else if (OldMethod->getFirstDecl()->isExplicitlyDefaulted() && !isFriend) {
3414 Diag(NewMethod->getLocation(),
3415 diag::err_definition_of_explicitly_defaulted_member)
3416 << getSpecialMember(OldMethod);
3421 // C++11 [dcl.attr.noreturn]p1:
3422 // The first declaration of a function shall specify the noreturn
3423 // attribute if any declaration of that function specifies the noreturn
3425 const CXX11NoReturnAttr *NRA = New->getAttr<CXX11NoReturnAttr>();
3426 if (NRA && !Old->hasAttr<CXX11NoReturnAttr>()) {
3427 Diag(NRA->getLocation(), diag::err_noreturn_missing_on_first_decl);
3428 Diag(Old->getFirstDecl()->getLocation(),
3429 diag::note_noreturn_missing_first_decl);
3432 // C++11 [dcl.attr.depend]p2:
3433 // The first declaration of a function shall specify the
3434 // carries_dependency attribute for its declarator-id if any declaration
3435 // of the function specifies the carries_dependency attribute.
3436 const CarriesDependencyAttr *CDA = New->getAttr<CarriesDependencyAttr>();
3437 if (CDA && !Old->hasAttr<CarriesDependencyAttr>()) {
3438 Diag(CDA->getLocation(),
3439 diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/;
3440 Diag(Old->getFirstDecl()->getLocation(),
3441 diag::note_carries_dependency_missing_first_decl) << 0/*Function*/;
3445 // All declarations for a function shall agree exactly in both the
3446 // return type and the parameter-type-list.
3447 // We also want to respect all the extended bits except noreturn.
3449 // noreturn should now match unless the old type info didn't have it.
3450 QualType OldQTypeForComparison = OldQType;
3451 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) {
3452 auto *OldType = OldQType->castAs<FunctionProtoType>();
3453 const FunctionType *OldTypeForComparison
3454 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true));
3455 OldQTypeForComparison = QualType(OldTypeForComparison, 0);
3456 assert(OldQTypeForComparison.isCanonical());
3459 if (haveIncompatibleLanguageLinkages(Old, New)) {
3460 // As a special case, retain the language linkage from previous
3461 // declarations of a friend function as an extension.
3463 // This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC
3464 // and is useful because there's otherwise no way to specify language
3465 // linkage within class scope.
3467 // Check cautiously as the friend object kind isn't yet complete.
3468 if (New->getFriendObjectKind() != Decl::FOK_None) {
3469 Diag(New->getLocation(), diag::ext_retained_language_linkage) << New;
3470 Diag(OldLocation, PrevDiag);
3472 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3473 Diag(OldLocation, PrevDiag);
3478 if (OldQTypeForComparison == NewQType)
3479 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3481 // If the types are imprecise (due to dependent constructs in friends or
3482 // local extern declarations), it's OK if they differ. We'll check again
3483 // during instantiation.
3484 if (!canFullyTypeCheckRedeclaration(New, Old, NewQType, OldQType))
3487 // Fall through for conflicting redeclarations and redefinitions.
3490 // C: Function types need to be compatible, not identical. This handles
3491 // duplicate function decls like "void f(int); void f(enum X);" properly.
3492 if (!getLangOpts().CPlusPlus &&
3493 Context.typesAreCompatible(OldQType, NewQType)) {
3494 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>();
3495 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>();
3496 const FunctionProtoType *OldProto = nullptr;
3497 if (MergeTypeWithOld && isa<FunctionNoProtoType>(NewFuncType) &&
3498 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) {
3499 // The old declaration provided a function prototype, but the
3500 // new declaration does not. Merge in the prototype.
3501 assert(!OldProto->hasExceptionSpec() && "Exception spec in C");
3502 SmallVector<QualType, 16> ParamTypes(OldProto->param_types());
3504 Context.getFunctionType(NewFuncType->getReturnType(), ParamTypes,
3505 OldProto->getExtProtoInfo());
3506 New->setType(NewQType);
3507 New->setHasInheritedPrototype();
3509 // Synthesize parameters with the same types.
3510 SmallVector<ParmVarDecl*, 16> Params;
3511 for (const auto &ParamType : OldProto->param_types()) {
3512 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(),
3513 SourceLocation(), nullptr,
3514 ParamType, /*TInfo=*/nullptr,
3516 Param->setScopeInfo(0, Params.size());
3517 Param->setImplicit();
3518 Params.push_back(Param);
3521 New->setParams(Params);
3524 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3527 // GNU C permits a K&R definition to follow a prototype declaration
3528 // if the declared types of the parameters in the K&R definition
3529 // match the types in the prototype declaration, even when the
3530 // promoted types of the parameters from the K&R definition differ
3531 // from the types in the prototype. GCC then keeps the types from
3534 // If a variadic prototype is followed by a non-variadic K&R definition,
3535 // the K&R definition becomes variadic. This is sort of an edge case, but
3536 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and
3538 if (!getLangOpts().CPlusPlus &&
3539 Old->hasPrototype() && !New->hasPrototype() &&
3540 New->getType()->getAs<FunctionProtoType>() &&
3541 Old->getNumParams() == New->getNumParams()) {
3542 SmallVector<QualType, 16> ArgTypes;
3543 SmallVector<GNUCompatibleParamWarning, 16> Warnings;
3544 const FunctionProtoType *OldProto
3545 = Old->getType()->getAs<FunctionProtoType>();
3546 const FunctionProtoType *NewProto
3547 = New->getType()->getAs<FunctionProtoType>();
3549 // Determine whether this is the GNU C extension.
3550 QualType MergedReturn = Context.mergeTypes(OldProto->getReturnType(),
3551 NewProto->getReturnType());
3552 bool LooseCompatible = !MergedReturn.isNull();
3553 for (unsigned Idx = 0, End = Old->getNumParams();
3554 LooseCompatible && Idx != End; ++Idx) {
3555 ParmVarDecl *OldParm = Old->getParamDecl(Idx);
3556 ParmVarDecl *NewParm = New->getParamDecl(Idx);
3557 if (Context.typesAreCompatible(OldParm->getType(),
3558 NewProto->getParamType(Idx))) {
3559 ArgTypes.push_back(NewParm->getType());
3560 } else if (Context.typesAreCompatible(OldParm->getType(),
3562 /*CompareUnqualified=*/true)) {
3563 GNUCompatibleParamWarning Warn = { OldParm, NewParm,
3564 NewProto->getParamType(Idx) };
3565 Warnings.push_back(Warn);
3566 ArgTypes.push_back(NewParm->getType());
3568 LooseCompatible = false;
3571 if (LooseCompatible) {
3572 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) {
3573 Diag(Warnings[Warn].NewParm->getLocation(),
3574 diag::ext_param_promoted_not_compatible_with_prototype)
3575 << Warnings[Warn].PromotedType
3576 << Warnings[Warn].OldParm->getType();
3577 if (Warnings[Warn].OldParm->getLocation().isValid())
3578 Diag(Warnings[Warn].OldParm->getLocation(),
3579 diag::note_previous_declaration);
3582 if (MergeTypeWithOld)
3583 New->setType(Context.getFunctionType(MergedReturn, ArgTypes,
3584 OldProto->getExtProtoInfo()));
3585 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3588 // Fall through to diagnose conflicting types.
3591 // A function that has already been declared has been redeclared or
3592 // defined with a different type; show an appropriate diagnostic.
3594 // If the previous declaration was an implicitly-generated builtin
3595 // declaration, then at the very least we should use a specialized note.
3597 if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) {
3598 // If it's actually a library-defined builtin function like 'malloc'
3599 // or 'printf', just warn about the incompatible redeclaration.
3600 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) {
3601 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New;
3602 Diag(OldLocation, diag::note_previous_builtin_declaration)
3603 << Old << Old->getType();
3605 // If this is a global redeclaration, just forget hereafter
3606 // about the "builtin-ness" of the function.
3608 // Doing this for local extern declarations is problematic. If
3609 // the builtin declaration remains visible, a second invalid
3610 // local declaration will produce a hard error; if it doesn't
3611 // remain visible, a single bogus local redeclaration (which is
3612 // actually only a warning) could break all the downstream code.
3613 if (!New->getLexicalDeclContext()->isFunctionOrMethod())
3614 New->getIdentifier()->revertBuiltin();
3619 PrevDiag = diag::note_previous_builtin_declaration;
3622 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName();
3623 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3627 /// Completes the merge of two function declarations that are
3628 /// known to be compatible.
3630 /// This routine handles the merging of attributes and other
3631 /// properties of function declarations from the old declaration to
3632 /// the new declaration, once we know that New is in fact a
3633 /// redeclaration of Old.
3636 bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
3637 Scope *S, bool MergeTypeWithOld) {
3638 // Merge the attributes
3639 mergeDeclAttributes(New, Old);
3641 // Merge "pure" flag.
3645 // Merge "used" flag.
3646 if (Old->getMostRecentDecl()->isUsed(false))
3649 // Merge attributes from the parameters. These can mismatch with K&R
3651 if (New->getNumParams() == Old->getNumParams())
3652 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) {
3653 ParmVarDecl *NewParam = New->getParamDecl(i);
3654 ParmVarDecl *OldParam = Old->getParamDecl(i);
3655 mergeParamDeclAttributes(NewParam, OldParam, *this);
3656 mergeParamDeclTypes(NewParam, OldParam, *this);
3659 if (getLangOpts().CPlusPlus)
3660 return MergeCXXFunctionDecl(New, Old, S);
3662 // Merge the function types so the we get the composite types for the return
3663 // and argument types. Per C11 6.2.7/4, only update the type if the old decl
3665 QualType Merged = Context.mergeTypes(Old->getType(), New->getType());
3666 if (!Merged.isNull() && MergeTypeWithOld)
3667 New->setType(Merged);
3672 void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod,
3673 ObjCMethodDecl *oldMethod) {
3674 // Merge the attributes, including deprecated/unavailable
3675 AvailabilityMergeKind MergeKind =
3676 isa<ObjCProtocolDecl>(oldMethod->getDeclContext())
3677 ? AMK_ProtocolImplementation
3678 : isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration
3681 mergeDeclAttributes(newMethod, oldMethod, MergeKind);
3683 // Merge attributes from the parameters.
3684 ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(),
3685 oe = oldMethod->param_end();
3686 for (ObjCMethodDecl::param_iterator
3687 ni = newMethod->param_begin(), ne = newMethod->param_end();
3688 ni != ne && oi != oe; ++ni, ++oi)
3689 mergeParamDeclAttributes(*ni, *oi, *this);
3691 CheckObjCMethodOverride(newMethod, oldMethod);
3694 static void diagnoseVarDeclTypeMismatch(Sema &S, VarDecl *New, VarDecl* Old) {
3695 assert(!S.Context.hasSameType(New->getType(), Old->getType()));
3697 S.Diag(New->getLocation(), New->isThisDeclarationADefinition()
3698 ? diag::err_redefinition_different_type
3699 : diag::err_redeclaration_different_type)
3700 << New->getDeclName() << New->getType() << Old->getType();
3702 diag::kind PrevDiag;
3703 SourceLocation OldLocation;
3704 std::tie(PrevDiag, OldLocation)
3705 = getNoteDiagForInvalidRedeclaration(Old, New);
3706 S.Diag(OldLocation, PrevDiag);
3707 New->setInvalidDecl();
3710 /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and
3711 /// scope as a previous declaration 'Old'. Figure out how to merge their types,
3712 /// emitting diagnostics as appropriate.
3714 /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back
3715 /// to here in AddInitializerToDecl. We can't check them before the initializer
3717 void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old,
3718 bool MergeTypeWithOld) {
3719 if (New->isInvalidDecl() || Old->isInvalidDecl())
3723 if (getLangOpts().CPlusPlus) {
3724 if (New->getType()->isUndeducedType()) {
3725 // We don't know what the new type is until the initializer is attached.
3727 } else if (Context.hasSameType(New->getType(), Old->getType())) {
3728 // These could still be something that needs exception specs checked.
3729 return MergeVarDeclExceptionSpecs(New, Old);
3731 // C++ [basic.link]p10:
3732 // [...] the types specified by all declarations referring to a given
3733 // object or function shall be identical, except that declarations for an
3734 // array object can specify array types that differ by the presence or
3735 // absence of a major array bound (8.3.4).
3736 else if (Old->getType()->isArrayType() && New->getType()->isArrayType()) {
3737 const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
3738 const ArrayType *NewArray = Context.getAsArrayType(New->getType());
3740 // We are merging a variable declaration New into Old. If it has an array
3741 // bound, and that bound differs from Old's bound, we should diagnose the
3743 if (!NewArray->isIncompleteArrayType() && !NewArray->isDependentType()) {
3744 for (VarDecl *PrevVD = Old->getMostRecentDecl(); PrevVD;
3745 PrevVD = PrevVD->getPreviousDecl()) {
3746 const ArrayType *PrevVDTy = Context.getAsArrayType(PrevVD->getType());
3747 if (PrevVDTy->isIncompleteArrayType() || PrevVDTy->isDependentType())
3750 if (!Context.hasSameType(NewArray, PrevVDTy))
3751 return diagnoseVarDeclTypeMismatch(*this, New, PrevVD);
3755 if (OldArray->isIncompleteArrayType() && NewArray->isArrayType()) {
3756 if (Context.hasSameType(OldArray->getElementType(),
3757 NewArray->getElementType()))
3758 MergedT = New->getType();
3760 // FIXME: Check visibility. New is hidden but has a complete type. If New
3761 // has no array bound, it should not inherit one from Old, if Old is not
3763 else if (OldArray->isArrayType() && NewArray->isIncompleteArrayType()) {
3764 if (Context.hasSameType(OldArray->getElementType(),
3765 NewArray->getElementType()))
3766 MergedT = Old->getType();
3769 else if (New->getType()->isObjCObjectPointerType() &&
3770 Old->getType()->isObjCObjectPointerType()) {
3771 MergedT = Context.mergeObjCGCQualifiers(New->getType(),
3776 // All declarations that refer to the same object or function shall have
3778 MergedT = Context.mergeTypes(New->getType(), Old->getType());
3780 if (MergedT.isNull()) {
3781 // It's OK if we couldn't merge types if either type is dependent, for a
3782 // block-scope variable. In other cases (static data members of class
3783 // templates, variable templates, ...), we require the types to be
3785 // FIXME: The C++ standard doesn't say anything about this.
3786 if ((New->getType()->isDependentType() ||
3787 Old->getType()->isDependentType()) && New->isLocalVarDecl()) {
3788 // If the old type was dependent, we can't merge with it, so the new type
3789 // becomes dependent for now. We'll reproduce the original type when we
3790 // instantiate the TypeSourceInfo for the variable.
3791 if (!New->getType()->isDependentType() && MergeTypeWithOld)
3792 New->setType(Context.DependentTy);
3795 return diagnoseVarDeclTypeMismatch(*this, New, Old);
3798 // Don't actually update the type on the new declaration if the old
3799 // declaration was an extern declaration in a different scope.
3800 if (MergeTypeWithOld)
3801 New->setType(MergedT);
3804 static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD,
3805 LookupResult &Previous) {
3807 // For an identifier with internal or external linkage declared
3808 // in a scope in which a prior declaration of that identifier is
3809 // visible, if the prior declaration specifies internal or
3810 // external linkage, the type of the identifier at the later
3811 // declaration becomes the composite type.
3813 // If the variable isn't visible, we do not merge with its type.
3814 if (Previous.isShadowed())
3817 if (S.getLangOpts().CPlusPlus) {
3818 // C++11 [dcl.array]p3:
3819 // If there is a preceding declaration of the entity in the same
3820 // scope in which the bound was specified, an omitted array bound
3821 // is taken to be the same as in that earlier declaration.
3822 return NewVD->isPreviousDeclInSameBlockScope() ||
3823 (!OldVD->getLexicalDeclContext()->isFunctionOrMethod() &&
3824 !NewVD->getLexicalDeclContext()->isFunctionOrMethod());
3826 // If the old declaration was function-local, don't merge with its
3827 // type unless we're in the same function.
3828 return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() ||
3829 OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext();
3833 /// MergeVarDecl - We just parsed a variable 'New' which has the same name
3834 /// and scope as a previous declaration 'Old'. Figure out how to resolve this
3835 /// situation, merging decls or emitting diagnostics as appropriate.
3837 /// Tentative definition rules (C99 6.9.2p2) are checked by
3838 /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative
3839 /// definitions here, since the initializer hasn't been attached.
3841 void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
3842 // If the new decl is already invalid, don't do any other checking.
3843 if (New->isInvalidDecl())
3846 if (!shouldLinkPossiblyHiddenDecl(Previous, New))
3849 VarTemplateDecl *NewTemplate = New->getDescribedVarTemplate();
3851 // Verify the old decl was also a variable or variable template.
3852 VarDecl *Old = nullptr;
3853 VarTemplateDecl *OldTemplate = nullptr;
3854 if (Previous.isSingleResult()) {
3856 OldTemplate = dyn_cast<VarTemplateDecl>(Previous.getFoundDecl());
3857 Old = OldTemplate ? OldTemplate->getTemplatedDecl() : nullptr;
3860 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3861 if (checkUsingShadowRedecl<VarTemplateDecl>(*this, Shadow, NewTemplate))
3862 return New->setInvalidDecl();
3864 Old = dyn_cast<VarDecl>(Previous.getFoundDecl());
3867 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3868 if (checkUsingShadowRedecl<VarDecl>(*this, Shadow, New))
3869 return New->setInvalidDecl();
3873 Diag(New->getLocation(), diag::err_redefinition_different_kind)
3874 << New->getDeclName();
3875 notePreviousDefinition(Previous.getRepresentativeDecl(),
3876 New->getLocation());
3877 return New->setInvalidDecl();
3880 // Ensure the template parameters are compatible.
3882 !TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
3883 OldTemplate->getTemplateParameters(),
3884 /*Complain=*/true, TPL_TemplateMatch))
3885 return New->setInvalidDecl();
3887 // C++ [class.mem]p1:
3888 // A member shall not be declared twice in the member-specification [...]
3890 // Here, we need only consider static data members.
3891 if (Old->isStaticDataMember() && !New->isOutOfLine()) {
3892 Diag(New->getLocation(), diag::err_duplicate_member)
3893 << New->getIdentifier();
3894 Diag(Old->getLocation(), diag::note_previous_declaration);
3895 New->setInvalidDecl();
3898 mergeDeclAttributes(New, Old);
3899 // Warn if an already-declared variable is made a weak_import in a subsequent
3901 if (New->hasAttr<WeakImportAttr>() &&
3902 Old->getStorageClass() == SC_None &&
3903 !Old->hasAttr<WeakImportAttr>()) {
3904 Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName();
3905 notePreviousDefinition(Old, New->getLocation());
3906 // Remove weak_import attribute on new declaration.
3907 New->dropAttr<WeakImportAttr>();
3910 if (New->hasAttr<InternalLinkageAttr>() &&
3911 !Old->hasAttr<InternalLinkageAttr>()) {
3912 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
3913 << New->getDeclName();
3914 notePreviousDefinition(Old, New->getLocation());
3915 New->dropAttr<InternalLinkageAttr>();
3919 VarDecl *MostRecent = Old->getMostRecentDecl();
3920 if (MostRecent != Old) {
3921 MergeVarDeclTypes(New, MostRecent,
3922 mergeTypeWithPrevious(*this, New, MostRecent, Previous));
3923 if (New->isInvalidDecl())
3927 MergeVarDeclTypes(New, Old, mergeTypeWithPrevious(*this, New, Old, Previous));
3928 if (New->isInvalidDecl())
3931 diag::kind PrevDiag;
3932 SourceLocation OldLocation;
3933 std::tie(PrevDiag, OldLocation) =
3934 getNoteDiagForInvalidRedeclaration(Old, New);
3936 // [dcl.stc]p8: Check if we have a non-static decl followed by a static.
3937 if (New->getStorageClass() == SC_Static &&
3938 !New->isStaticDataMember() &&
3939 Old->hasExternalFormalLinkage()) {
3940 if (getLangOpts().MicrosoftExt) {
3941 Diag(New->getLocation(), diag::ext_static_non_static)
3942 << New->getDeclName();
3943 Diag(OldLocation, PrevDiag);
3945 Diag(New->getLocation(), diag::err_static_non_static)
3946 << New->getDeclName();
3947 Diag(OldLocation, PrevDiag);
3948 return New->setInvalidDecl();
3952 // For an identifier declared with the storage-class specifier
3953 // extern in a scope in which a prior declaration of that
3954 // identifier is visible,23) if the prior declaration specifies
3955 // internal or external linkage, the linkage of the identifier at
3956 // the later declaration is the same as the linkage specified at
3957 // the prior declaration. If no prior declaration is visible, or
3958 // if the prior declaration specifies no linkage, then the
3959 // identifier has external linkage.
3960 if (New->hasExternalStorage() && Old->hasLinkage())
3962 else if (New->getCanonicalDecl()->getStorageClass() != SC_Static &&
3963 !New->isStaticDataMember() &&
3964 Old->getCanonicalDecl()->getStorageClass() == SC_Static) {
3965 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName();
3966 Diag(OldLocation, PrevDiag);
3967 return New->setInvalidDecl();
3970 // Check if extern is followed by non-extern and vice-versa.
3971 if (New->hasExternalStorage() &&
3972 !Old->hasLinkage() && Old->isLocalVarDeclOrParm()) {
3973 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName();
3974 Diag(OldLocation, PrevDiag);
3975 return New->setInvalidDecl();
3977 if (Old->hasLinkage() && New->isLocalVarDeclOrParm() &&
3978 !New->hasExternalStorage()) {
3979 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName();
3980 Diag(OldLocation, PrevDiag);
3981 return New->setInvalidDecl();
3984 if (CheckRedeclarationModuleOwnership(New, Old))
3987 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup.
3989 // FIXME: The test for external storage here seems wrong? We still
3990 // need to check for mismatches.
3991 if (!New->hasExternalStorage() && !New->isFileVarDecl() &&
3992 // Don't complain about out-of-line definitions of static members.
3993 !(Old->getLexicalDeclContext()->isRecord() &&
3994 !New->getLexicalDeclContext()->isRecord())) {
3995 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName();
3996 Diag(OldLocation, PrevDiag);
3997 return New->setInvalidDecl();
4000 if (New->isInline() && !Old->getMostRecentDecl()->isInline()) {
4001 if (VarDecl *Def = Old->getDefinition()) {
4002 // C++1z [dcl.fcn.spec]p4:
4003 // If the definition of a variable appears in a translation unit before
4004 // its first declaration as inline, the program is ill-formed.
4005 Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
4006 Diag(Def->getLocation(), diag::note_previous_definition);
4010 // If this redeclaration makes the variable inline, we may need to add it to
4011 // UndefinedButUsed.
4012 if (!Old->isInline() && New->isInline() && Old->isUsed(false) &&
4013 !Old->getDefinition() && !New->isThisDeclarationADefinition())
4014 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
4017 if (New->getTLSKind() != Old->getTLSKind()) {
4018 if (!Old->getTLSKind()) {
4019 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName();
4020 Diag(OldLocation, PrevDiag);
4021 } else if (!New->getTLSKind()) {
4022 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName();
4023 Diag(OldLocation, PrevDiag);
4025 // Do not allow redeclaration to change the variable between requiring
4026 // static and dynamic initialization.
4027 // FIXME: GCC allows this, but uses the TLS keyword on the first
4028 // declaration to determine the kind. Do we need to be compatible here?
4029 Diag(New->getLocation(), diag::err_thread_thread_different_kind)
4030 << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic);
4031 Diag(OldLocation, PrevDiag);
4035 // C++ doesn't have tentative definitions, so go right ahead and check here.
4036 if (getLangOpts().CPlusPlus &&
4037 New->isThisDeclarationADefinition() == VarDecl::Definition) {
4038 if (Old->isStaticDataMember() && Old->getCanonicalDecl()->isInline() &&
4039 Old->getCanonicalDecl()->isConstexpr()) {
4040 // This definition won't be a definition any more once it's been merged.
4041 Diag(New->getLocation(),
4042 diag::warn_deprecated_redundant_constexpr_static_def);
4043 } else if (VarDecl *Def = Old->getDefinition()) {
4044 if (checkVarDeclRedefinition(Def, New))
4049 if (haveIncompatibleLanguageLinkages(Old, New)) {
4050 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
4051 Diag(OldLocation, PrevDiag);
4052 New->setInvalidDecl();
4056 // Merge "used" flag.
4057 if (Old->getMostRecentDecl()->isUsed(false))
4060 // Keep a chain of previous declarations.
4061 New->setPreviousDecl(Old);
4063 NewTemplate->setPreviousDecl(OldTemplate);
4064 adjustDeclContextForDeclaratorDecl(New, Old);
4066 // Inherit access appropriately.
4067 New->setAccess(Old->getAccess());
4069 NewTemplate->setAccess(New->getAccess());
4071 if (Old->isInline())
4072 New->setImplicitlyInline();
4075 void Sema::notePreviousDefinition(const NamedDecl *Old, SourceLocation New) {
4076 SourceManager &SrcMgr = getSourceManager();
4077 auto FNewDecLoc = SrcMgr.getDecomposedLoc(New);
4078 auto FOldDecLoc = SrcMgr.getDecomposedLoc(Old->getLocation());
4079 auto *FNew = SrcMgr.getFileEntryForID(FNewDecLoc.first);
4080 auto *FOld = SrcMgr.getFileEntryForID(FOldDecLoc.first);
4081 auto &HSI = PP.getHeaderSearchInfo();
4082 StringRef HdrFilename =
4083 SrcMgr.getFilename(SrcMgr.getSpellingLoc(Old->getLocation()));
4085 auto noteFromModuleOrInclude = [&](Module *Mod,
4086 SourceLocation IncLoc) -> bool {
4087 // Redefinition errors with modules are common with non modular mapped
4088 // headers, example: a non-modular header H in module A that also gets
4089 // included directly in a TU. Pointing twice to the same header/definition
4090 // is confusing, try to get better diagnostics when modules is on.
4091 if (IncLoc.isValid()) {
4093 Diag(IncLoc, diag::note_redefinition_modules_same_file)
4094 << HdrFilename.str() << Mod->getFullModuleName();
4095 if (!Mod->DefinitionLoc.isInvalid())
4096 Diag(Mod->DefinitionLoc, diag::note_defined_here)
4097 << Mod->getFullModuleName();
4099 Diag(IncLoc, diag::note_redefinition_include_same_file)
4100 << HdrFilename.str();
4108 // Is it the same file and same offset? Provide more information on why
4109 // this leads to a redefinition error.
4110 bool EmittedDiag = false;
4111 if (FNew == FOld && FNewDecLoc.second == FOldDecLoc.second) {
4112 SourceLocation OldIncLoc = SrcMgr.getIncludeLoc(FOldDecLoc.first);
4113 SourceLocation NewIncLoc = SrcMgr.getIncludeLoc(FNewDecLoc.first);
4114 EmittedDiag = noteFromModuleOrInclude(Old->getOwningModule(), OldIncLoc);
4115 EmittedDiag |= noteFromModuleOrInclude(getCurrentModule(), NewIncLoc);
4117 // If the header has no guards, emit a note suggesting one.
4118 if (FOld && !HSI.isFileMultipleIncludeGuarded(FOld))
4119 Diag(Old->getLocation(), diag::note_use_ifdef_guards);
4125 // Redefinition coming from different files or couldn't do better above.
4126 if (Old->getLocation().isValid())
4127 Diag(Old->getLocation(), diag::note_previous_definition);
4130 /// We've just determined that \p Old and \p New both appear to be definitions
4131 /// of the same variable. Either diagnose or fix the problem.
4132 bool Sema::checkVarDeclRedefinition(VarDecl *Old, VarDecl *New) {
4133 if (!hasVisibleDefinition(Old) &&
4134 (New->getFormalLinkage() == InternalLinkage ||
4136 New->getDescribedVarTemplate() ||
4137 New->getNumTemplateParameterLists() ||
4138 New->getDeclContext()->isDependentContext())) {
4139 // The previous definition is hidden, and multiple definitions are
4140 // permitted (in separate TUs). Demote this to a declaration.
4141 New->demoteThisDefinitionToDeclaration();
4143 // Make the canonical definition visible.
4144 if (auto *OldTD = Old->getDescribedVarTemplate())
4145 makeMergedDefinitionVisible(OldTD);
4146 makeMergedDefinitionVisible(Old);
4149 Diag(New->getLocation(), diag::err_redefinition) << New;
4150 notePreviousDefinition(Old, New->getLocation());
4151 New->setInvalidDecl();
4156 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
4157 /// no declarator (e.g. "struct foo;") is parsed.
4159 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
4160 RecordDecl *&AnonRecord) {
4161 return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg(), false,
4165 // The MS ABI changed between VS2013 and VS2015 with regard to numbers used to
4166 // disambiguate entities defined in different scopes.
4167 // While the VS2015 ABI fixes potential miscompiles, it is also breaks
4169 // We will pick our mangling number depending on which version of MSVC is being
4171 static unsigned getMSManglingNumber(const LangOptions &LO, Scope *S) {
4172 return LO.isCompatibleWithMSVC(LangOptions::MSVC2015)
4173 ? S->getMSCurManglingNumber()
4174 : S->getMSLastManglingNumber();
4177 void Sema::handleTagNumbering(const TagDecl *Tag, Scope *TagScope) {
4178 if (!Context.getLangOpts().CPlusPlus)
4181 if (isa<CXXRecordDecl>(Tag->getParent())) {
4182 // If this tag is the direct child of a class, number it if
4184 if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl())
4186 MangleNumberingContext &MCtx =
4187 Context.getManglingNumberContext(Tag->getParent());
4188 Context.setManglingNumber(
4189 Tag, MCtx.getManglingNumber(
4190 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
4194 // If this tag isn't a direct child of a class, number it if it is local.
4195 Decl *ManglingContextDecl;
4196 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
4197 Tag->getDeclContext(), ManglingContextDecl)) {
4198 Context.setManglingNumber(
4199 Tag, MCtx->getManglingNumber(
4200 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
4204 void Sema::setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,
4205 TypedefNameDecl *NewTD) {
4206 if (TagFromDeclSpec->isInvalidDecl())
4209 // Do nothing if the tag already has a name for linkage purposes.
4210 if (TagFromDeclSpec->hasNameForLinkage())
4213 // A well-formed anonymous tag must always be a TUK_Definition.
4214 assert(TagFromDeclSpec->isThisDeclarationADefinition());
4216 // The type must match the tag exactly; no qualifiers allowed.
4217 if (!Context.hasSameType(NewTD->getUnderlyingType(),
4218 Context.getTagDeclType(TagFromDeclSpec))) {
4219 if (getLangOpts().CPlusPlus)
4220 Context.addTypedefNameForUnnamedTagDecl(TagFromDeclSpec, NewTD);
4224 // If we've already computed linkage for the anonymous tag, then
4225 // adding a typedef name for the anonymous decl can change that
4226 // linkage, which might be a serious problem. Diagnose this as
4227 // unsupported and ignore the typedef name. TODO: we should
4228 // pursue this as a language defect and establish a formal rule
4229 // for how to handle it.
4230 if (TagFromDeclSpec->hasLinkageBeenComputed()) {
4231 Diag(NewTD->getLocation(), diag::err_typedef_changes_linkage);
4233 SourceLocation tagLoc = TagFromDeclSpec->getInnerLocStart();
4234 tagLoc = getLocForEndOfToken(tagLoc);
4236 llvm::SmallString<40> textToInsert;
4237 textToInsert += ' ';
4238 textToInsert += NewTD->getIdentifier()->getName();
4239 Diag(tagLoc, diag::note_typedef_changes_linkage)
4240 << FixItHint::CreateInsertion(tagLoc, textToInsert);
4244 // Otherwise, set this is the anon-decl typedef for the tag.
4245 TagFromDeclSpec->setTypedefNameForAnonDecl(NewTD);
4248 static unsigned GetDiagnosticTypeSpecifierID(DeclSpec::TST T) {
4250 case DeclSpec::TST_class:
4252 case DeclSpec::TST_struct:
4254 case DeclSpec::TST_interface:
4256 case DeclSpec::TST_union:
4258 case DeclSpec::TST_enum:
4261 llvm_unreachable("unexpected type specifier");
4265 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
4266 /// no declarator (e.g. "struct foo;") is parsed. It also accepts template
4267 /// parameters to cope with template friend declarations.
4269 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
4270 MultiTemplateParamsArg TemplateParams,
4271 bool IsExplicitInstantiation,
4272 RecordDecl *&AnonRecord) {
4273 Decl *TagD = nullptr;
4274 TagDecl *Tag = nullptr;
4275 if (DS.getTypeSpecType() == DeclSpec::TST_class ||
4276 DS.getTypeSpecType() == DeclSpec::TST_struct ||
4277 DS.getTypeSpecType() == DeclSpec::TST_interface ||
4278 DS.getTypeSpecType() == DeclSpec::TST_union ||
4279 DS.getTypeSpecType() == DeclSpec::TST_enum) {
4280 TagD = DS.getRepAsDecl();
4282 if (!TagD) // We probably had an error
4285 // Note that the above type specs guarantee that the
4286 // type rep is a Decl, whereas in many of the others
4288 if (isa<TagDecl>(TagD))
4289 Tag = cast<TagDecl>(TagD);
4290 else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD))
4291 Tag = CTD->getTemplatedDecl();
4295 handleTagNumbering(Tag, S);
4296 Tag->setFreeStanding();
4297 if (Tag->isInvalidDecl())
4301 if (unsigned TypeQuals = DS.getTypeQualifiers()) {
4302 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object
4303 // or incomplete types shall not be restrict-qualified."
4304 if (TypeQuals & DeclSpec::TQ_restrict)
4305 Diag(DS.getRestrictSpecLoc(),
4306 diag::err_typecheck_invalid_restrict_not_pointer_noarg)
4307 << DS.getSourceRange();
4310 if (DS.isInlineSpecified())
4311 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
4312 << getLangOpts().CPlusPlus17;
4314 if (DS.hasConstexprSpecifier()) {
4315 // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations
4316 // and definitions of functions and variables.
4317 // C++2a [dcl.constexpr]p1: The consteval specifier shall be applied only to
4318 // the declaration of a function or function template
4319 bool IsConsteval = DS.getConstexprSpecifier() == CSK_consteval;
4321 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag)
4322 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) << IsConsteval;
4324 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_wrong_decl_kind)
4326 // Don't emit warnings after this error.
4330 DiagnoseFunctionSpecifiers(DS);
4332 if (DS.isFriendSpecified()) {
4333 // If we're dealing with a decl but not a TagDecl, assume that
4334 // whatever routines created it handled the friendship aspect.
4337 return ActOnFriendTypeDecl(S, DS, TemplateParams);
4340 const CXXScopeSpec &SS = DS.getTypeSpecScope();
4341 bool IsExplicitSpecialization =
4342 !TemplateParams.empty() && TemplateParams.back()->size() == 0;
4343 if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() &&
4344 !IsExplicitInstantiation && !IsExplicitSpecialization &&
4345 !isa<ClassTemplatePartialSpecializationDecl>(Tag)) {
4346 // Per C++ [dcl.type.elab]p1, a class declaration cannot have a
4347 // nested-name-specifier unless it is an explicit instantiation
4348 // or an explicit specialization.
4350 // FIXME: We allow class template partial specializations here too, per the
4351 // obvious intent of DR1819.
4353 // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either.
4354 Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier)
4355 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) << SS.getRange();
4359 // Track whether this decl-specifier declares anything.
4360 bool DeclaresAnything = true;
4362 // Handle anonymous struct definitions.
4363 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
4364 if (!Record->getDeclName() && Record->isCompleteDefinition() &&
4365 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) {
4366 if (getLangOpts().CPlusPlus ||
4367 Record->getDeclContext()->isRecord()) {
4368 // If CurContext is a DeclContext that can contain statements,
4369 // RecursiveASTVisitor won't visit the decls that
4370 // BuildAnonymousStructOrUnion() will put into CurContext.
4371 // Also store them here so that they can be part of the
4372 // DeclStmt that gets created in this case.
4373 // FIXME: Also return the IndirectFieldDecls created by
4374 // BuildAnonymousStructOr union, for the same reason?
4375 if (CurContext->isFunctionOrMethod())
4376 AnonRecord = Record;
4377 return BuildAnonymousStructOrUnion(S, DS, AS, Record,
4378 Context.getPrintingPolicy());
4381 DeclaresAnything = false;
4386 // A struct-declaration that does not declare an anonymous structure or
4387 // anonymous union shall contain a struct-declarator-list.
4389 // This rule also existed in C89 and C99; the grammar for struct-declaration
4390 // did not permit a struct-declaration without a struct-declarator-list.
4391 if (!getLangOpts().CPlusPlus && CurContext->isRecord() &&
4392 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) {
4393 // Check for Microsoft C extension: anonymous struct/union member.
4394 // Handle 2 kinds of anonymous struct/union:
4398 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct.
4399 // UNION_TYPE; <- where UNION_TYPE is a typedef union.
4400 if ((Tag && Tag->getDeclName()) ||
4401 DS.getTypeSpecType() == DeclSpec::TST_typename) {
4402 RecordDecl *Record = nullptr;
4404 Record = dyn_cast<RecordDecl>(Tag);
4405 else if (const RecordType *RT =
4406 DS.getRepAsType().get()->getAsStructureType())
4407 Record = RT->getDecl();
4408 else if (const RecordType *UT = DS.getRepAsType().get()->getAsUnionType())
4409 Record = UT->getDecl();
4411 if (Record && getLangOpts().MicrosoftExt) {
4412 Diag(DS.getBeginLoc(), diag::ext_ms_anonymous_record)
4413 << Record->isUnion() << DS.getSourceRange();
4414 return BuildMicrosoftCAnonymousStruct(S, DS, Record);
4417 DeclaresAnything = false;
4421 // Skip all the checks below if we have a type error.
4422 if (DS.getTypeSpecType() == DeclSpec::TST_error ||
4423 (TagD && TagD->isInvalidDecl()))
4426 if (getLangOpts().CPlusPlus &&
4427 DS.getStorageClassSpec() != DeclSpec::SCS_typedef)
4428 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag))
4429 if (Enum->enumerator_begin() == Enum->enumerator_end() &&
4430 !Enum->getIdentifier() && !Enum->isInvalidDecl())
4431 DeclaresAnything = false;
4433 if (!DS.isMissingDeclaratorOk()) {
4434 // Customize diagnostic for a typedef missing a name.
4435 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
4436 Diag(DS.getBeginLoc(), diag::ext_typedef_without_a_name)
4437 << DS.getSourceRange();
4439 DeclaresAnything = false;
4442 if (DS.isModulePrivateSpecified() &&
4443 Tag && Tag->getDeclContext()->isFunctionOrMethod())
4444 Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class)
4445 << Tag->getTagKind()
4446 << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc());
4448 ActOnDocumentableDecl(TagD);
4451 // A declaration [...] shall declare at least a declarator [...], a tag,
4452 // or the members of an enumeration.
4454 // [If there are no declarators], and except for the declaration of an
4455 // unnamed bit-field, the decl-specifier-seq shall introduce one or more
4456 // names into the program, or shall redeclare a name introduced by a
4457 // previous declaration.
4458 if (!DeclaresAnything) {
4459 // In C, we allow this as a (popular) extension / bug. Don't bother
4460 // producing further diagnostics for redundant qualifiers after this.
4461 Diag(DS.getBeginLoc(), diag::ext_no_declarators) << DS.getSourceRange();
4466 // If a storage-class-specifier appears in a decl-specifier-seq, [...] the
4467 // init-declarator-list of the declaration shall not be empty.
4468 // C++ [dcl.fct.spec]p1:
4469 // If a cv-qualifier appears in a decl-specifier-seq, the
4470 // init-declarator-list of the declaration shall not be empty.
4472 // Spurious qualifiers here appear to be valid in C.
4473 unsigned DiagID = diag::warn_standalone_specifier;
4474 if (getLangOpts().CPlusPlus)
4475 DiagID = diag::ext_standalone_specifier;
4477 // Note that a linkage-specification sets a storage class, but
4478 // 'extern "C" struct foo;' is actually valid and not theoretically
4480 if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
4481 if (SCS == DeclSpec::SCS_mutable)
4482 // Since mutable is not a viable storage class specifier in C, there is
4483 // no reason to treat it as an extension. Instead, diagnose as an error.
4484 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_nonmember);
4485 else if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef)
4486 Diag(DS.getStorageClassSpecLoc(), DiagID)
4487 << DeclSpec::getSpecifierName(SCS);
4490 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
4491 Diag(DS.getThreadStorageClassSpecLoc(), DiagID)
4492 << DeclSpec::getSpecifierName(TSCS);
4493 if (DS.getTypeQualifiers()) {
4494 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4495 Diag(DS.getConstSpecLoc(), DiagID) << "const";
4496 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4497 Diag(DS.getConstSpecLoc(), DiagID) << "volatile";
4498 // Restrict is covered above.
4499 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4500 Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic";
4501 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4502 Diag(DS.getUnalignedSpecLoc(), DiagID) << "__unaligned";
4505 // Warn about ignored type attributes, for example:
4506 // __attribute__((aligned)) struct A;
4507 // Attributes should be placed after tag to apply to type declaration.
4508 if (!DS.getAttributes().empty()) {
4509 DeclSpec::TST TypeSpecType = DS.getTypeSpecType();
4510 if (TypeSpecType == DeclSpec::TST_class ||
4511 TypeSpecType == DeclSpec::TST_struct ||
4512 TypeSpecType == DeclSpec::TST_interface ||
4513 TypeSpecType == DeclSpec::TST_union ||
4514 TypeSpecType == DeclSpec::TST_enum) {
4515 for (const ParsedAttr &AL : DS.getAttributes())
4516 Diag(AL.getLoc(), diag::warn_declspec_attribute_ignored)
4517 << AL.getName() << GetDiagnosticTypeSpecifierID(TypeSpecType);
4524 /// We are trying to inject an anonymous member into the given scope;
4525 /// check if there's an existing declaration that can't be overloaded.
4527 /// \return true if this is a forbidden redeclaration
4528 static bool CheckAnonMemberRedeclaration(Sema &SemaRef,
4531 DeclarationName Name,
4532 SourceLocation NameLoc,
4534 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName,
4535 Sema::ForVisibleRedeclaration);
4536 if (!SemaRef.LookupName(R, S)) return false;
4538 // Pick a representative declaration.
4539 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl();
4540 assert(PrevDecl && "Expected a non-null Decl");
4542 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S))
4545 SemaRef.Diag(NameLoc, diag::err_anonymous_record_member_redecl)
4547 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
4552 /// InjectAnonymousStructOrUnionMembers - Inject the members of the
4553 /// anonymous struct or union AnonRecord into the owning context Owner
4554 /// and scope S. This routine will be invoked just after we realize
4555 /// that an unnamed union or struct is actually an anonymous union or
4562 /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and
4563 /// // f into the surrounding scope.x
4566 /// This routine is recursive, injecting the names of nested anonymous
4567 /// structs/unions into the owning context and scope as well.
4569 InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, DeclContext *Owner,
4570 RecordDecl *AnonRecord, AccessSpecifier AS,
4571 SmallVectorImpl<NamedDecl *> &Chaining) {
4572 bool Invalid = false;
4574 // Look every FieldDecl and IndirectFieldDecl with a name.
4575 for (auto *D : AnonRecord->decls()) {
4576 if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) &&
4577 cast<NamedDecl>(D)->getDeclName()) {
4578 ValueDecl *VD = cast<ValueDecl>(D);
4579 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(),
4581 AnonRecord->isUnion())) {
4582 // C++ [class.union]p2:
4583 // The names of the members of an anonymous union shall be
4584 // distinct from the names of any other entity in the
4585 // scope in which the anonymous union is declared.
4588 // C++ [class.union]p2:
4589 // For the purpose of name lookup, after the anonymous union
4590 // definition, the members of the anonymous union are
4591 // considered to have been defined in the scope in which the
4592 // anonymous union is declared.
4593 unsigned OldChainingSize = Chaining.size();
4594 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD))
4595 Chaining.append(IF->chain_begin(), IF->chain_end());
4597 Chaining.push_back(VD);
4599 assert(Chaining.size() >= 2);
4600 NamedDecl **NamedChain =
4601 new (SemaRef.Context)NamedDecl*[Chaining.size()];
4602 for (unsigned i = 0; i < Chaining.size(); i++)
4603 NamedChain[i] = Chaining[i];
4605 IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
4606 SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(),
4607 VD->getType(), {NamedChain, Chaining.size()});
4609 for (const auto *Attr : VD->attrs())
4610 IndirectField->addAttr(Attr->clone(SemaRef.Context));
4612 IndirectField->setAccess(AS);
4613 IndirectField->setImplicit();
4614 SemaRef.PushOnScopeChains(IndirectField, S);
4616 // That includes picking up the appropriate access specifier.
4617 if (AS != AS_none) IndirectField->setAccess(AS);
4619 Chaining.resize(OldChainingSize);
4627 /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to
4628 /// a VarDecl::StorageClass. Any error reporting is up to the caller:
4629 /// illegal input values are mapped to SC_None.
4631 StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) {
4632 DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec();
4633 assert(StorageClassSpec != DeclSpec::SCS_typedef &&
4634 "Parser allowed 'typedef' as storage class VarDecl.");
4635 switch (StorageClassSpec) {
4636 case DeclSpec::SCS_unspecified: return SC_None;
4637 case DeclSpec::SCS_extern:
4638 if (DS.isExternInLinkageSpec())
4641 case DeclSpec::SCS_static: return SC_Static;
4642 case DeclSpec::SCS_auto: return SC_Auto;
4643 case DeclSpec::SCS_register: return SC_Register;
4644 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
4645 // Illegal SCSs map to None: error reporting is up to the caller.
4646 case DeclSpec::SCS_mutable: // Fall through.
4647 case DeclSpec::SCS_typedef: return SC_None;
4649 llvm_unreachable("unknown storage class specifier");
4652 static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) {
4653 assert(Record->hasInClassInitializer());
4655 for (const auto *I : Record->decls()) {
4656 const auto *FD = dyn_cast<FieldDecl>(I);
4657 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
4658 FD = IFD->getAnonField();
4659 if (FD && FD->hasInClassInitializer())
4660 return FD->getLocation();
4663 llvm_unreachable("couldn't find in-class initializer");
4666 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4667 SourceLocation DefaultInitLoc) {
4668 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4671 S.Diag(DefaultInitLoc, diag::err_multiple_mem_union_initialization);
4672 S.Diag(findDefaultInitializer(Parent), diag::note_previous_initializer) << 0;
4675 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4676 CXXRecordDecl *AnonUnion) {
4677 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4680 checkDuplicateDefaultInit(S, Parent, findDefaultInitializer(AnonUnion));
4683 /// BuildAnonymousStructOrUnion - Handle the declaration of an
4684 /// anonymous structure or union. Anonymous unions are a C++ feature
4685 /// (C++ [class.union]) and a C11 feature; anonymous structures
4686 /// are a C11 feature and GNU C++ extension.
4687 Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
4690 const PrintingPolicy &Policy) {
4691 DeclContext *Owner = Record->getDeclContext();
4693 // Diagnose whether this anonymous struct/union is an extension.
4694 if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11)
4695 Diag(Record->getLocation(), diag::ext_anonymous_union);
4696 else if (!Record->isUnion() && getLangOpts().CPlusPlus)
4697 Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct);
4698 else if (!Record->isUnion() && !getLangOpts().C11)
4699 Diag(Record->getLocation(), diag::ext_c11_anonymous_struct);
4701 // C and C++ require different kinds of checks for anonymous
4703 bool Invalid = false;
4704 if (getLangOpts().CPlusPlus) {
4705 const char *PrevSpec = nullptr;
4707 if (Record->isUnion()) {
4708 // C++ [class.union]p6:
4709 // C++17 [class.union.anon]p2:
4710 // Anonymous unions declared in a named namespace or in the
4711 // global namespace shall be declared static.
4712 DeclContext *OwnerScope = Owner->getRedeclContext();
4713 if (DS.getStorageClassSpec() != DeclSpec::SCS_static &&
4714 (OwnerScope->isTranslationUnit() ||
4715 (OwnerScope->isNamespace() &&
4716 !cast<NamespaceDecl>(OwnerScope)->isAnonymousNamespace()))) {
4717 Diag(Record->getLocation(), diag::err_anonymous_union_not_static)
4718 << FixItHint::CreateInsertion(Record->getLocation(), "static ");
4720 // Recover by adding 'static'.
4721 DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(),
4722 PrevSpec, DiagID, Policy);
4724 // C++ [class.union]p6:
4725 // A storage class is not allowed in a declaration of an
4726 // anonymous union in a class scope.
4727 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
4728 isa<RecordDecl>(Owner)) {
4729 Diag(DS.getStorageClassSpecLoc(),
4730 diag::err_anonymous_union_with_storage_spec)
4731 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
4733 // Recover by removing the storage specifier.
4734 DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified,
4736 PrevSpec, DiagID, Context.getPrintingPolicy());
4740 // Ignore const/volatile/restrict qualifiers.
4741 if (DS.getTypeQualifiers()) {
4742 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4743 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified)
4744 << Record->isUnion() << "const"
4745 << FixItHint::CreateRemoval(DS.getConstSpecLoc());
4746 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4747 Diag(DS.getVolatileSpecLoc(),
4748 diag::ext_anonymous_struct_union_qualified)
4749 << Record->isUnion() << "volatile"
4750 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc());
4751 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
4752 Diag(DS.getRestrictSpecLoc(),
4753 diag::ext_anonymous_struct_union_qualified)
4754 << Record->isUnion() << "restrict"
4755 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc());
4756 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4757 Diag(DS.getAtomicSpecLoc(),
4758 diag::ext_anonymous_struct_union_qualified)
4759 << Record->isUnion() << "_Atomic"
4760 << FixItHint::CreateRemoval(DS.getAtomicSpecLoc());
4761 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4762 Diag(DS.getUnalignedSpecLoc(),
4763 diag::ext_anonymous_struct_union_qualified)
4764 << Record->isUnion() << "__unaligned"
4765 << FixItHint::CreateRemoval(DS.getUnalignedSpecLoc());
4767 DS.ClearTypeQualifiers();
4770 // C++ [class.union]p2:
4771 // The member-specification of an anonymous union shall only
4772 // define non-static data members. [Note: nested types and
4773 // functions cannot be declared within an anonymous union. ]
4774 for (auto *Mem : Record->decls()) {
4775 if (auto *FD = dyn_cast<FieldDecl>(Mem)) {
4776 // C++ [class.union]p3:
4777 // An anonymous union shall not have private or protected
4778 // members (clause 11).
4779 assert(FD->getAccess() != AS_none);
4780 if (FD->getAccess() != AS_public) {
4781 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member)
4782 << Record->isUnion() << (FD->getAccess() == AS_protected);
4786 // C++ [class.union]p1
4787 // An object of a class with a non-trivial constructor, a non-trivial
4788 // copy constructor, a non-trivial destructor, or a non-trivial copy
4789 // assignment operator cannot be a member of a union, nor can an
4790 // array of such objects.
4791 if (CheckNontrivialField(FD))
4793 } else if (Mem->isImplicit()) {
4794 // Any implicit members are fine.
4795 } else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) {
4796 // This is a type that showed up in an
4797 // elaborated-type-specifier inside the anonymous struct or
4798 // union, but which actually declares a type outside of the
4799 // anonymous struct or union. It's okay.
4800 } else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) {
4801 if (!MemRecord->isAnonymousStructOrUnion() &&
4802 MemRecord->getDeclName()) {
4803 // Visual C++ allows type definition in anonymous struct or union.
4804 if (getLangOpts().MicrosoftExt)
4805 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type)
4806 << Record->isUnion();
4808 // This is a nested type declaration.
4809 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type)
4810 << Record->isUnion();
4814 // This is an anonymous type definition within another anonymous type.
4815 // This is a popular extension, provided by Plan9, MSVC and GCC, but
4816 // not part of standard C++.
4817 Diag(MemRecord->getLocation(),
4818 diag::ext_anonymous_record_with_anonymous_type)
4819 << Record->isUnion();
4821 } else if (isa<AccessSpecDecl>(Mem)) {
4822 // Any access specifier is fine.
4823 } else if (isa<StaticAssertDecl>(Mem)) {
4824 // In C++1z, static_assert declarations are also fine.
4826 // We have something that isn't a non-static data
4827 // member. Complain about it.
4828 unsigned DK = diag::err_anonymous_record_bad_member;
4829 if (isa<TypeDecl>(Mem))
4830 DK = diag::err_anonymous_record_with_type;
4831 else if (isa<FunctionDecl>(Mem))
4832 DK = diag::err_anonymous_record_with_function;
4833 else if (isa<VarDecl>(Mem))
4834 DK = diag::err_anonymous_record_with_static;
4836 // Visual C++ allows type definition in anonymous struct or union.
4837 if (getLangOpts().MicrosoftExt &&
4838 DK == diag::err_anonymous_record_with_type)
4839 Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type)
4840 << Record->isUnion();
4842 Diag(Mem->getLocation(), DK) << Record->isUnion();
4848 // C++11 [class.union]p8 (DR1460):
4849 // At most one variant member of a union may have a
4850 // brace-or-equal-initializer.
4851 if (cast<CXXRecordDecl>(Record)->hasInClassInitializer() &&
4853 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Owner),
4854 cast<CXXRecordDecl>(Record));
4857 if (!Record->isUnion() && !Owner->isRecord()) {
4858 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member)
4859 << getLangOpts().CPlusPlus;
4864 // [If there are no declarators], and except for the declaration of an
4865 // unnamed bit-field, the decl-specifier-seq shall introduce one or more
4866 // names into the program
4867 // C++ [class.mem]p2:
4868 // each such member-declaration shall either declare at least one member
4869 // name of the class or declare at least one unnamed bit-field
4871 // For C this is an error even for a named struct, and is diagnosed elsewhere.
4872 if (getLangOpts().CPlusPlus && Record->field_empty())
4873 Diag(DS.getBeginLoc(), diag::ext_no_declarators) << DS.getSourceRange();
4875 // Mock up a declarator.
4876 Declarator Dc(DS, DeclaratorContext::MemberContext);
4877 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4878 assert(TInfo && "couldn't build declarator info for anonymous struct/union");
4880 // Create a declaration for this anonymous struct/union.
4881 NamedDecl *Anon = nullptr;
4882 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) {
4883 Anon = FieldDecl::Create(
4884 Context, OwningClass, DS.getBeginLoc(), Record->getLocation(),
4885 /*IdentifierInfo=*/nullptr, Context.getTypeDeclType(Record), TInfo,
4886 /*BitWidth=*/nullptr, /*Mutable=*/false,
4887 /*InitStyle=*/ICIS_NoInit);
4888 Anon->setAccess(AS);
4889 if (getLangOpts().CPlusPlus)
4890 FieldCollector->Add(cast<FieldDecl>(Anon));
4892 DeclSpec::SCS SCSpec = DS.getStorageClassSpec();
4893 StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS);
4894 if (SCSpec == DeclSpec::SCS_mutable) {
4895 // mutable can only appear on non-static class members, so it's always
4897 Diag(Record->getLocation(), diag::err_mutable_nonmember);
4902 Anon = VarDecl::Create(Context, Owner, DS.getBeginLoc(),
4903 Record->getLocation(), /*IdentifierInfo=*/nullptr,
4904 Context.getTypeDeclType(Record), TInfo, SC);
4906 // Default-initialize the implicit variable. This initialization will be
4907 // trivial in almost all cases, except if a union member has an in-class
4909 // union { int n = 0; };
4910 ActOnUninitializedDecl(Anon);
4912 Anon->setImplicit();
4914 // Mark this as an anonymous struct/union type.
4915 Record->setAnonymousStructOrUnion(true);
4917 // Add the anonymous struct/union object to the current
4918 // context. We'll be referencing this object when we refer to one of
4920 Owner->addDecl(Anon);
4922 // Inject the members of the anonymous struct/union into the owning
4923 // context and into the identifier resolver chain for name lookup
4925 SmallVector<NamedDecl*, 2> Chain;
4926 Chain.push_back(Anon);
4928 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, Chain))
4931 if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) {
4932 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
4933 Decl *ManglingContextDecl;
4934 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
4935 NewVD->getDeclContext(), ManglingContextDecl)) {
4936 Context.setManglingNumber(
4937 NewVD, MCtx->getManglingNumber(
4938 NewVD, getMSManglingNumber(getLangOpts(), S)));
4939 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
4945 Anon->setInvalidDecl();
4950 /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an
4951 /// Microsoft C anonymous structure.
4952 /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx
4955 /// struct A { int a; };
4956 /// struct B { struct A; int b; };
4963 Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
4964 RecordDecl *Record) {
4965 assert(Record && "expected a record!");
4967 // Mock up a declarator.
4968 Declarator Dc(DS, DeclaratorContext::TypeNameContext);
4969 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4970 assert(TInfo && "couldn't build declarator info for anonymous struct");
4972 auto *ParentDecl = cast<RecordDecl>(CurContext);
4973 QualType RecTy = Context.getTypeDeclType(Record);
4975 // Create a declaration for this anonymous struct.
4977 FieldDecl::Create(Context, ParentDecl, DS.getBeginLoc(), DS.getBeginLoc(),
4978 /*IdentifierInfo=*/nullptr, RecTy, TInfo,
4979 /*BitWidth=*/nullptr, /*Mutable=*/false,
4980 /*InitStyle=*/ICIS_NoInit);
4981 Anon->setImplicit();
4983 // Add the anonymous struct object to the current context.
4984 CurContext->addDecl(Anon);
4986 // Inject the members of the anonymous struct into the current
4987 // context and into the identifier resolver chain for name lookup
4989 SmallVector<NamedDecl*, 2> Chain;
4990 Chain.push_back(Anon);
4992 RecordDecl *RecordDef = Record->getDefinition();
4993 if (RequireCompleteType(Anon->getLocation(), RecTy,
4994 diag::err_field_incomplete) ||
4995 InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef,
4997 Anon->setInvalidDecl();
4998 ParentDecl->setInvalidDecl();
5004 /// GetNameForDeclarator - Determine the full declaration name for the
5005 /// given Declarator.
5006 DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) {
5007 return GetNameFromUnqualifiedId(D.getName());
5010 /// Retrieves the declaration name from a parsed unqualified-id.
5012 Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
5013 DeclarationNameInfo NameInfo;
5014 NameInfo.setLoc(Name.StartLocation);
5016 switch (Name.getKind()) {
5018 case UnqualifiedIdKind::IK_ImplicitSelfParam:
5019 case UnqualifiedIdKind::IK_Identifier:
5020 NameInfo.setName(Name.Identifier);
5023 case UnqualifiedIdKind::IK_DeductionGuideName: {
5024 // C++ [temp.deduct.guide]p3:
5025 // The simple-template-id shall name a class template specialization.
5026 // The template-name shall be the same identifier as the template-name
5027 // of the simple-template-id.
5028 // These together intend to imply that the template-name shall name a
5030 // FIXME: template<typename T> struct X {};
5031 // template<typename T> using Y = X<T>;
5032 // Y(int) -> Y<int>;
5033 // satisfies these rules but does not name a class template.
5034 TemplateName TN = Name.TemplateName.get().get();
5035 auto *Template = TN.getAsTemplateDecl();
5036 if (!Template || !isa<ClassTemplateDecl>(Template)) {
5037 Diag(Name.StartLocation,
5038 diag::err_deduction_guide_name_not_class_template)
5039 << (int)getTemplateNameKindForDiagnostics(TN) << TN;
5041 Diag(Template->getLocation(), diag::note_template_decl_here);
5042 return DeclarationNameInfo();
5046 Context.DeclarationNames.getCXXDeductionGuideName(Template));
5050 case UnqualifiedIdKind::IK_OperatorFunctionId:
5051 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName(
5052 Name.OperatorFunctionId.Operator));
5053 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc
5054 = Name.OperatorFunctionId.SymbolLocations[0];
5055 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc
5056 = Name.EndLocation.getRawEncoding();
5059 case UnqualifiedIdKind::IK_LiteralOperatorId:
5060 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName(
5062 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation);
5065 case UnqualifiedIdKind::IK_ConversionFunctionId: {
5066 TypeSourceInfo *TInfo;
5067 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo);
5069 return DeclarationNameInfo();
5070 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName(
5071 Context.getCanonicalType(Ty)));
5072 NameInfo.setNamedTypeInfo(TInfo);
5076 case UnqualifiedIdKind::IK_ConstructorName: {
5077 TypeSourceInfo *TInfo;
5078 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo);
5080 return DeclarationNameInfo();
5081 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
5082 Context.getCanonicalType(Ty)));
5083 NameInfo.setNamedTypeInfo(TInfo);
5087 case UnqualifiedIdKind::IK_ConstructorTemplateId: {
5088 // In well-formed code, we can only have a constructor
5089 // template-id that refers to the current context, so go there
5090 // to find the actual type being constructed.
5091 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext);
5092 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name)
5093 return DeclarationNameInfo();
5095 // Determine the type of the class being constructed.
5096 QualType CurClassType = Context.getTypeDeclType(CurClass);
5098 // FIXME: Check two things: that the template-id names the same type as
5099 // CurClassType, and that the template-id does not occur when the name
5102 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
5103 Context.getCanonicalType(CurClassType)));
5104 // FIXME: should we retrieve TypeSourceInfo?
5105 NameInfo.setNamedTypeInfo(nullptr);
5109 case UnqualifiedIdKind::IK_DestructorName: {
5110 TypeSourceInfo *TInfo;
5111 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo);
5113 return DeclarationNameInfo();
5114 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName(
5115 Context.getCanonicalType(Ty)));
5116 NameInfo.setNamedTypeInfo(TInfo);
5120 case UnqualifiedIdKind::IK_TemplateId: {
5121 TemplateName TName = Name.TemplateId->Template.get();
5122 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc;
5123 return Context.getNameForTemplate(TName, TNameLoc);
5126 } // switch (Name.getKind())
5128 llvm_unreachable("Unknown name kind");
5131 static QualType getCoreType(QualType Ty) {
5133 if (Ty->isPointerType() || Ty->isReferenceType())
5134 Ty = Ty->getPointeeType();
5135 else if (Ty->isArrayType())
5136 Ty = Ty->castAsArrayTypeUnsafe()->getElementType();
5138 return Ty.withoutLocalFastQualifiers();
5142 /// hasSimilarParameters - Determine whether the C++ functions Declaration
5143 /// and Definition have "nearly" matching parameters. This heuristic is
5144 /// used to improve diagnostics in the case where an out-of-line function
5145 /// definition doesn't match any declaration within the class or namespace.
5146 /// Also sets Params to the list of indices to the parameters that differ
5147 /// between the declaration and the definition. If hasSimilarParameters
5148 /// returns true and Params is empty, then all of the parameters match.
5149 static bool hasSimilarParameters(ASTContext &Context,
5150 FunctionDecl *Declaration,
5151 FunctionDecl *Definition,
5152 SmallVectorImpl<unsigned> &Params) {
5154 if (Declaration->param_size() != Definition->param_size())
5156 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) {
5157 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType();
5158 QualType DefParamTy = Definition->getParamDecl(Idx)->getType();
5160 // The parameter types are identical
5161 if (Context.hasSameUnqualifiedType(DefParamTy, DeclParamTy))
5164 QualType DeclParamBaseTy = getCoreType(DeclParamTy);
5165 QualType DefParamBaseTy = getCoreType(DefParamTy);
5166 const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier();
5167 const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier();
5169 if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) ||
5170 (DeclTyName && DeclTyName == DefTyName))
5171 Params.push_back(Idx);
5172 else // The two parameters aren't even close
5179 /// NeedsRebuildingInCurrentInstantiation - Checks whether the given
5180 /// declarator needs to be rebuilt in the current instantiation.
5181 /// Any bits of declarator which appear before the name are valid for
5182 /// consideration here. That's specifically the type in the decl spec
5183 /// and the base type in any member-pointer chunks.
5184 static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D,
5185 DeclarationName Name) {
5186 // The types we specifically need to rebuild are:
5187 // - typenames, typeofs, and decltypes
5188 // - types which will become injected class names
5189 // Of course, we also need to rebuild any type referencing such a
5190 // type. It's safest to just say "dependent", but we call out a
5193 DeclSpec &DS = D.getMutableDeclSpec();
5194 switch (DS.getTypeSpecType()) {
5195 case DeclSpec::TST_typename:
5196 case DeclSpec::TST_typeofType:
5197 case DeclSpec::TST_underlyingType:
5198 case DeclSpec::TST_atomic: {
5199 // Grab the type from the parser.
5200 TypeSourceInfo *TSI = nullptr;
5201 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI);
5202 if (T.isNull() || !T->isDependentType()) break;
5204 // Make sure there's a type source info. This isn't really much
5205 // of a waste; most dependent types should have type source info
5206 // attached already.
5208 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc());
5210 // Rebuild the type in the current instantiation.
5211 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name);
5212 if (!TSI) return true;
5214 // Store the new type back in the decl spec.
5215 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI);
5216 DS.UpdateTypeRep(LocType);
5220 case DeclSpec::TST_decltype:
5221 case DeclSpec::TST_typeofExpr: {
5222 Expr *E = DS.getRepAsExpr();
5223 ExprResult Result = S.RebuildExprInCurrentInstantiation(E);
5224 if (Result.isInvalid()) return true;
5225 DS.UpdateExprRep(Result.get());
5230 // Nothing to do for these decl specs.
5234 // It doesn't matter what order we do this in.
5235 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
5236 DeclaratorChunk &Chunk = D.getTypeObject(I);
5238 // The only type information in the declarator which can come
5239 // before the declaration name is the base type of a member
5241 if (Chunk.Kind != DeclaratorChunk::MemberPointer)
5244 // Rebuild the scope specifier in-place.
5245 CXXScopeSpec &SS = Chunk.Mem.Scope();
5246 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS))
5253 Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) {
5254 D.setFunctionDefinitionKind(FDK_Declaration);
5255 Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg());
5257 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() &&
5258 Dcl && Dcl->getDeclContext()->isFileContext())
5259 Dcl->setTopLevelDeclInObjCContainer();
5261 if (getLangOpts().OpenCL)
5262 setCurrentOpenCLExtensionForDecl(Dcl);
5267 /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13:
5268 /// If T is the name of a class, then each of the following shall have a
5269 /// name different from T:
5270 /// - every static data member of class T;
5271 /// - every member function of class T
5272 /// - every member of class T that is itself a type;
5273 /// \returns true if the declaration name violates these rules.
5274 bool Sema::DiagnoseClassNameShadow(DeclContext *DC,
5275 DeclarationNameInfo NameInfo) {
5276 DeclarationName Name = NameInfo.getName();
5278 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC);
5279 while (Record && Record->isAnonymousStructOrUnion())
5280 Record = dyn_cast<CXXRecordDecl>(Record->getParent());
5281 if (Record && Record->getIdentifier() && Record->getDeclName() == Name) {
5282 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name;
5289 /// Diagnose a declaration whose declarator-id has the given
5290 /// nested-name-specifier.
5292 /// \param SS The nested-name-specifier of the declarator-id.
5294 /// \param DC The declaration context to which the nested-name-specifier
5297 /// \param Name The name of the entity being declared.
5299 /// \param Loc The location of the name of the entity being declared.
5301 /// \param IsTemplateId Whether the name is a (simple-)template-id, and thus
5302 /// we're declaring an explicit / partial specialization / instantiation.
5304 /// \returns true if we cannot safely recover from this error, false otherwise.
5305 bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
5306 DeclarationName Name,
5307 SourceLocation Loc, bool IsTemplateId) {
5308 DeclContext *Cur = CurContext;
5309 while (isa<LinkageSpecDecl>(Cur) || isa<CapturedDecl>(Cur))
5310 Cur = Cur->getParent();
5312 // If the user provided a superfluous scope specifier that refers back to the
5313 // class in which the entity is already declared, diagnose and ignore it.
5319 // Note, it was once ill-formed to give redundant qualification in all
5320 // contexts, but that rule was removed by DR482.
5321 if (Cur->Equals(DC)) {
5322 if (Cur->isRecord()) {
5323 Diag(Loc, LangOpts.MicrosoftExt ? diag::warn_member_extra_qualification
5324 : diag::err_member_extra_qualification)
5325 << Name << FixItHint::CreateRemoval(SS.getRange());
5328 Diag(Loc, diag::warn_namespace_member_extra_qualification) << Name;
5333 // Check whether the qualifying scope encloses the scope of the original
5334 // declaration. For a template-id, we perform the checks in
5335 // CheckTemplateSpecializationScope.
5336 if (!Cur->Encloses(DC) && !IsTemplateId) {
5337 if (Cur->isRecord())
5338 Diag(Loc, diag::err_member_qualification)
5339 << Name << SS.getRange();
5340 else if (isa<TranslationUnitDecl>(DC))
5341 Diag(Loc, diag::err_invalid_declarator_global_scope)
5342 << Name << SS.getRange();
5343 else if (isa<FunctionDecl>(Cur))
5344 Diag(Loc, diag::err_invalid_declarator_in_function)
5345 << Name << SS.getRange();
5346 else if (isa<BlockDecl>(Cur))
5347 Diag(Loc, diag::err_invalid_declarator_in_block)
5348 << Name << SS.getRange();
5350 Diag(Loc, diag::err_invalid_declarator_scope)
5351 << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange();
5356 if (Cur->isRecord()) {
5357 // Cannot qualify members within a class.
5358 Diag(Loc, diag::err_member_qualification)
5359 << Name << SS.getRange();
5362 // C++ constructors and destructors with incorrect scopes can break
5363 // our AST invariants by having the wrong underlying types. If
5364 // that's the case, then drop this declaration entirely.
5365 if ((Name.getNameKind() == DeclarationName::CXXConstructorName ||
5366 Name.getNameKind() == DeclarationName::CXXDestructorName) &&
5367 !Context.hasSameType(Name.getCXXNameType(),
5368 Context.getTypeDeclType(cast<CXXRecordDecl>(Cur))))
5374 // C++11 [dcl.meaning]p1:
5375 // [...] "The nested-name-specifier of the qualified declarator-id shall
5376 // not begin with a decltype-specifer"
5377 NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data());
5378 while (SpecLoc.getPrefix())
5379 SpecLoc = SpecLoc.getPrefix();
5380 if (dyn_cast_or_null<DecltypeType>(
5381 SpecLoc.getNestedNameSpecifier()->getAsType()))
5382 Diag(Loc, diag::err_decltype_in_declarator)
5383 << SpecLoc.getTypeLoc().getSourceRange();
5388 NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
5389 MultiTemplateParamsArg TemplateParamLists) {
5390 // TODO: consider using NameInfo for diagnostic.
5391 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
5392 DeclarationName Name = NameInfo.getName();
5394 // All of these full declarators require an identifier. If it doesn't have
5395 // one, the ParsedFreeStandingDeclSpec action should be used.
5396 if (D.isDecompositionDeclarator()) {
5397 return ActOnDecompositionDeclarator(S, D, TemplateParamLists);
5399 if (!D.isInvalidType()) // Reject this if we think it is valid.
5400 Diag(D.getDeclSpec().getBeginLoc(), diag::err_declarator_need_ident)
5401 << D.getDeclSpec().getSourceRange() << D.getSourceRange();
5403 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType))
5406 // The scope passed in may not be a decl scope. Zip up the scope tree until
5407 // we find one that is.
5408 while ((S->getFlags() & Scope::DeclScope) == 0 ||
5409 (S->getFlags() & Scope::TemplateParamScope) != 0)
5412 DeclContext *DC = CurContext;
5413 if (D.getCXXScopeSpec().isInvalid())
5415 else if (D.getCXXScopeSpec().isSet()) {
5416 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(),
5417 UPPC_DeclarationQualifier))
5420 bool EnteringContext = !D.getDeclSpec().isFriendSpecified();
5421 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext);
5422 if (!DC || isa<EnumDecl>(DC)) {
5423 // If we could not compute the declaration context, it's because the
5424 // declaration context is dependent but does not refer to a class,
5425 // class template, or class template partial specialization. Complain
5426 // and return early, to avoid the coming semantic disaster.
5427 Diag(D.getIdentifierLoc(),
5428 diag::err_template_qualified_declarator_no_match)
5429 << D.getCXXScopeSpec().getScopeRep()
5430 << D.getCXXScopeSpec().getRange();
5433 bool IsDependentContext = DC->isDependentContext();
5435 if (!IsDependentContext &&
5436 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC))
5439 // If a class is incomplete, do not parse entities inside it.
5440 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) {
5441 Diag(D.getIdentifierLoc(),
5442 diag::err_member_def_undefined_record)
5443 << Name << DC << D.getCXXScopeSpec().getRange();
5446 if (!D.getDeclSpec().isFriendSpecified()) {
5447 if (diagnoseQualifiedDeclaration(
5448 D.getCXXScopeSpec(), DC, Name, D.getIdentifierLoc(),
5449 D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId)) {
5457 // Check whether we need to rebuild the type of the given
5458 // declaration in the current instantiation.
5459 if (EnteringContext && IsDependentContext &&
5460 TemplateParamLists.size() != 0) {
5461 ContextRAII SavedContext(*this, DC);
5462 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name))
5467 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
5468 QualType R = TInfo->getType();
5470 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
5471 UPPC_DeclarationType))
5474 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
5475 forRedeclarationInCurContext());
5477 // See if this is a redefinition of a variable in the same scope.
5478 if (!D.getCXXScopeSpec().isSet()) {
5479 bool IsLinkageLookup = false;
5480 bool CreateBuiltins = false;
5482 // If the declaration we're planning to build will be a function
5483 // or object with linkage, then look for another declaration with
5484 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6).
5486 // If the declaration we're planning to build will be declared with
5487 // external linkage in the translation unit, create any builtin with
5489 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
5491 else if (CurContext->isFunctionOrMethod() &&
5492 (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern ||
5493 R->isFunctionType())) {
5494 IsLinkageLookup = true;
5496 CurContext->getEnclosingNamespaceContext()->isTranslationUnit();
5497 } else if (CurContext->getRedeclContext()->isTranslationUnit() &&
5498 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
5499 CreateBuiltins = true;
5501 if (IsLinkageLookup) {
5502 Previous.clear(LookupRedeclarationWithLinkage);
5503 Previous.setRedeclarationKind(ForExternalRedeclaration);
5506 LookupName(Previous, S, CreateBuiltins);
5507 } else { // Something like "int foo::x;"
5508 LookupQualifiedName(Previous, DC);
5510 // C++ [dcl.meaning]p1:
5511 // When the declarator-id is qualified, the declaration shall refer to a
5512 // previously declared member of the class or namespace to which the
5513 // qualifier refers (or, in the case of a namespace, of an element of the
5514 // inline namespace set of that namespace (7.3.1)) or to a specialization
5517 // Note that we already checked the context above, and that we do not have
5518 // enough information to make sure that Previous contains the declaration
5519 // we want to match. For example, given:
5526 // void X::f(int) { } // ill-formed
5528 // In this case, Previous will point to the overload set
5529 // containing the two f's declared in X, but neither of them
5532 // C++ [dcl.meaning]p1:
5533 // [...] the member shall not merely have been introduced by a
5534 // using-declaration in the scope of the class or namespace nominated by
5535 // the nested-name-specifier of the declarator-id.
5536 RemoveUsingDecls(Previous);
5539 if (Previous.isSingleResult() &&
5540 Previous.getFoundDecl()->isTemplateParameter()) {
5541 // Maybe we will complain about the shadowed template parameter.
5542 if (!D.isInvalidType())
5543 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
5544 Previous.getFoundDecl());
5546 // Just pretend that we didn't see the previous declaration.
5550 if (!R->isFunctionType() && DiagnoseClassNameShadow(DC, NameInfo))
5551 // Forget that the previous declaration is the injected-class-name.
5554 // In C++, the previous declaration we find might be a tag type
5555 // (class or enum). In this case, the new declaration will hide the
5556 // tag type. Note that this applies to functions, function templates, and
5557 // variables, but not to typedefs (C++ [dcl.typedef]p4) or variable templates.
5558 if (Previous.isSingleTagDecl() &&
5559 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
5560 (TemplateParamLists.size() == 0 || R->isFunctionType()))
5563 // Check that there are no default arguments other than in the parameters
5564 // of a function declaration (C++ only).
5565 if (getLangOpts().CPlusPlus)
5566 CheckExtraCXXDefaultArguments(D);
5570 bool AddToScope = true;
5571 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
5572 if (TemplateParamLists.size()) {
5573 Diag(D.getIdentifierLoc(), diag::err_template_typedef);
5577 New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous);
5578 } else if (R->isFunctionType()) {
5579 New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous,
5583 New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists,
5590 // If this has an identifier and is not a function template specialization,
5591 // add it to the scope stack.
5592 if (New->getDeclName() && AddToScope)
5593 PushOnScopeChains(New, S);
5595 if (isInOpenMPDeclareTargetContext())
5596 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
5601 /// Helper method to turn variable array types into constant array
5602 /// types in certain situations which would otherwise be errors (for
5603 /// GCC compatibility).
5604 static QualType TryToFixInvalidVariablyModifiedType(QualType T,
5605 ASTContext &Context,
5606 bool &SizeIsNegative,
5607 llvm::APSInt &Oversized) {
5608 // This method tries to turn a variable array into a constant
5609 // array even when the size isn't an ICE. This is necessary
5610 // for compatibility with code that depends on gcc's buggy
5611 // constant expression folding, like struct {char x[(int)(char*)2];}
5612 SizeIsNegative = false;
5615 if (T->isDependentType())
5618 QualifierCollector Qs;
5619 const Type *Ty = Qs.strip(T);
5621 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) {
5622 QualType Pointee = PTy->getPointeeType();
5623 QualType FixedType =
5624 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative,
5626 if (FixedType.isNull()) return FixedType;
5627 FixedType = Context.getPointerType(FixedType);
5628 return Qs.apply(Context, FixedType);
5630 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) {
5631 QualType Inner = PTy->getInnerType();
5632 QualType FixedType =
5633 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative,
5635 if (FixedType.isNull()) return FixedType;
5636 FixedType = Context.getParenType(FixedType);
5637 return Qs.apply(Context, FixedType);
5640 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T);
5643 // FIXME: We should probably handle this case
5644 if (VLATy->getElementType()->isVariablyModifiedType())
5647 Expr::EvalResult Result;
5648 if (!VLATy->getSizeExpr() ||
5649 !VLATy->getSizeExpr()->EvaluateAsInt(Result, Context))
5652 llvm::APSInt Res = Result.Val.getInt();
5654 // Check whether the array size is negative.
5655 if (Res.isSigned() && Res.isNegative()) {
5656 SizeIsNegative = true;
5660 // Check whether the array is too large to be addressed.
5661 unsigned ActiveSizeBits
5662 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(),
5664 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
5669 return Context.getConstantArrayType(VLATy->getElementType(),
5670 Res, ArrayType::Normal, 0);
5674 FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) {
5675 SrcTL = SrcTL.getUnqualifiedLoc();
5676 DstTL = DstTL.getUnqualifiedLoc();
5677 if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) {
5678 PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>();
5679 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(),
5680 DstPTL.getPointeeLoc());
5681 DstPTL.setStarLoc(SrcPTL.getStarLoc());
5684 if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) {
5685 ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>();
5686 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(),
5687 DstPTL.getInnerLoc());
5688 DstPTL.setLParenLoc(SrcPTL.getLParenLoc());
5689 DstPTL.setRParenLoc(SrcPTL.getRParenLoc());
5692 ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>();
5693 ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>();
5694 TypeLoc SrcElemTL = SrcATL.getElementLoc();
5695 TypeLoc DstElemTL = DstATL.getElementLoc();
5696 DstElemTL.initializeFullCopy(SrcElemTL);
5697 DstATL.setLBracketLoc(SrcATL.getLBracketLoc());
5698 DstATL.setSizeExpr(SrcATL.getSizeExpr());
5699 DstATL.setRBracketLoc(SrcATL.getRBracketLoc());
5702 /// Helper method to turn variable array types into constant array
5703 /// types in certain situations which would otherwise be errors (for
5704 /// GCC compatibility).
5705 static TypeSourceInfo*
5706 TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo,
5707 ASTContext &Context,
5708 bool &SizeIsNegative,
5709 llvm::APSInt &Oversized) {
5711 = TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context,
5712 SizeIsNegative, Oversized);
5713 if (FixedTy.isNull())
5715 TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy);
5716 FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(),
5717 FixedTInfo->getTypeLoc());
5721 /// Register the given locally-scoped extern "C" declaration so
5722 /// that it can be found later for redeclarations. We include any extern "C"
5723 /// declaration that is not visible in the translation unit here, not just
5724 /// function-scope declarations.
5726 Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) {
5727 if (!getLangOpts().CPlusPlus &&
5728 ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit())
5729 // Don't need to track declarations in the TU in C.
5732 // Note that we have a locally-scoped external with this name.
5733 Context.getExternCContextDecl()->makeDeclVisibleInContext(ND);
5736 NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) {
5737 // FIXME: We can have multiple results via __attribute__((overloadable)).
5738 auto Result = Context.getExternCContextDecl()->lookup(Name);
5739 return Result.empty() ? nullptr : *Result.begin();
5742 /// Diagnose function specifiers on a declaration of an identifier that
5743 /// does not identify a function.
5744 void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) {
5745 // FIXME: We should probably indicate the identifier in question to avoid
5746 // confusion for constructs like "virtual int a(), b;"
5747 if (DS.isVirtualSpecified())
5748 Diag(DS.getVirtualSpecLoc(),
5749 diag::err_virtual_non_function);
5751 if (DS.hasExplicitSpecifier())
5752 Diag(DS.getExplicitSpecLoc(),
5753 diag::err_explicit_non_function);
5755 if (DS.isNoreturnSpecified())
5756 Diag(DS.getNoreturnSpecLoc(),
5757 diag::err_noreturn_non_function);
5761 Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
5762 TypeSourceInfo *TInfo, LookupResult &Previous) {
5763 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1).
5764 if (D.getCXXScopeSpec().isSet()) {
5765 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator)
5766 << D.getCXXScopeSpec().getRange();
5768 // Pretend we didn't see the scope specifier.
5773 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5775 if (D.getDeclSpec().isInlineSpecified())
5776 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
5777 << getLangOpts().CPlusPlus17;
5778 if (D.getDeclSpec().hasConstexprSpecifier())
5779 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr)
5780 << 1 << (D.getDeclSpec().getConstexprSpecifier() == CSK_consteval);
5782 if (D.getName().Kind != UnqualifiedIdKind::IK_Identifier) {
5783 if (D.getName().Kind == UnqualifiedIdKind::IK_DeductionGuideName)
5784 Diag(D.getName().StartLocation,
5785 diag::err_deduction_guide_invalid_specifier)
5788 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier)
5789 << D.getName().getSourceRange();
5793 TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo);
5794 if (!NewTD) return nullptr;
5796 // Handle attributes prior to checking for duplicates in MergeVarDecl
5797 ProcessDeclAttributes(S, NewTD, D);
5799 CheckTypedefForVariablyModifiedType(S, NewTD);
5801 bool Redeclaration = D.isRedeclaration();
5802 NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration);
5803 D.setRedeclaration(Redeclaration);
5808 Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) {
5809 // C99 6.7.7p2: If a typedef name specifies a variably modified type
5810 // then it shall have block scope.
5811 // Note that variably modified types must be fixed before merging the decl so
5812 // that redeclarations will match.
5813 TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo();
5814 QualType T = TInfo->getType();
5815 if (T->isVariablyModifiedType()) {
5816 setFunctionHasBranchProtectedScope();
5818 if (S->getFnParent() == nullptr) {
5819 bool SizeIsNegative;
5820 llvm::APSInt Oversized;
5821 TypeSourceInfo *FixedTInfo =
5822 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
5826 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size);
5827 NewTD->setTypeSourceInfo(FixedTInfo);
5830 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size);
5831 else if (T->isVariableArrayType())
5832 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope);
5833 else if (Oversized.getBoolValue())
5834 Diag(NewTD->getLocation(), diag::err_array_too_large)
5835 << Oversized.toString(10);
5837 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope);
5838 NewTD->setInvalidDecl();
5844 /// ActOnTypedefNameDecl - Perform semantic checking for a declaration which
5845 /// declares a typedef-name, either using the 'typedef' type specifier or via
5846 /// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'.
5848 Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD,
5849 LookupResult &Previous, bool &Redeclaration) {
5851 // Find the shadowed declaration before filtering for scope.
5852 NamedDecl *ShadowedDecl = getShadowedDeclaration(NewTD, Previous);
5854 // Merge the decl with the existing one if appropriate. If the decl is
5855 // in an outer scope, it isn't the same thing.
5856 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/false,
5857 /*AllowInlineNamespace*/false);
5858 filterNonConflictingPreviousTypedefDecls(*this, NewTD, Previous);
5859 if (!Previous.empty()) {
5860 Redeclaration = true;
5861 MergeTypedefNameDecl(S, NewTD, Previous);
5864 if (ShadowedDecl && !Redeclaration)
5865 CheckShadow(NewTD, ShadowedDecl, Previous);
5867 // If this is the C FILE type, notify the AST context.
5868 if (IdentifierInfo *II = NewTD->getIdentifier())
5869 if (!NewTD->isInvalidDecl() &&
5870 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
5871 if (II->isStr("FILE"))
5872 Context.setFILEDecl(NewTD);
5873 else if (II->isStr("jmp_buf"))
5874 Context.setjmp_bufDecl(NewTD);
5875 else if (II->isStr("sigjmp_buf"))
5876 Context.setsigjmp_bufDecl(NewTD);
5877 else if (II->isStr("ucontext_t"))
5878 Context.setucontext_tDecl(NewTD);
5884 /// Determines whether the given declaration is an out-of-scope
5885 /// previous declaration.
5887 /// This routine should be invoked when name lookup has found a
5888 /// previous declaration (PrevDecl) that is not in the scope where a
5889 /// new declaration by the same name is being introduced. If the new
5890 /// declaration occurs in a local scope, previous declarations with
5891 /// linkage may still be considered previous declarations (C99
5892 /// 6.2.2p4-5, C++ [basic.link]p6).
5894 /// \param PrevDecl the previous declaration found by name
5897 /// \param DC the context in which the new declaration is being
5900 /// \returns true if PrevDecl is an out-of-scope previous declaration
5901 /// for a new delcaration with the same name.
5903 isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC,
5904 ASTContext &Context) {
5908 if (!PrevDecl->hasLinkage())
5911 if (Context.getLangOpts().CPlusPlus) {
5912 // C++ [basic.link]p6:
5913 // If there is a visible declaration of an entity with linkage
5914 // having the same name and type, ignoring entities declared
5915 // outside the innermost enclosing namespace scope, the block
5916 // scope declaration declares that same entity and receives the
5917 // linkage of the previous declaration.
5918 DeclContext *OuterContext = DC->getRedeclContext();
5919 if (!OuterContext->isFunctionOrMethod())
5920 // This rule only applies to block-scope declarations.
5923 DeclContext *PrevOuterContext = PrevDecl->getDeclContext();
5924 if (PrevOuterContext->isRecord())
5925 // We found a member function: ignore it.
5928 // Find the innermost enclosing namespace for the new and
5929 // previous declarations.
5930 OuterContext = OuterContext->getEnclosingNamespaceContext();
5931 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext();
5933 // The previous declaration is in a different namespace, so it
5934 // isn't the same function.
5935 if (!OuterContext->Equals(PrevOuterContext))
5942 static void SetNestedNameSpecifier(Sema &S, DeclaratorDecl *DD, Declarator &D) {
5943 CXXScopeSpec &SS = D.getCXXScopeSpec();
5944 if (!SS.isSet()) return;
5945 DD->setQualifierInfo(SS.getWithLocInContext(S.Context));
5948 bool Sema::inferObjCARCLifetime(ValueDecl *decl) {
5949 QualType type = decl->getType();
5950 Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime();
5951 if (lifetime == Qualifiers::OCL_Autoreleasing) {
5952 // Various kinds of declaration aren't allowed to be __autoreleasing.
5953 unsigned kind = -1U;
5954 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5955 if (var->hasAttr<BlocksAttr>())
5956 kind = 0; // __block
5957 else if (!var->hasLocalStorage())
5959 } else if (isa<ObjCIvarDecl>(decl)) {
5961 } else if (isa<FieldDecl>(decl)) {
5966 Diag(decl->getLocation(), diag::err_arc_autoreleasing_var)
5969 } else if (lifetime == Qualifiers::OCL_None) {
5970 // Try to infer lifetime.
5971 if (!type->isObjCLifetimeType())
5974 lifetime = type->getObjCARCImplicitLifetime();
5975 type = Context.getLifetimeQualifiedType(type, lifetime);
5976 decl->setType(type);
5979 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5980 // Thread-local variables cannot have lifetime.
5981 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone &&
5982 var->getTLSKind()) {
5983 Diag(var->getLocation(), diag::err_arc_thread_ownership)
5992 static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) {
5993 // Ensure that an auto decl is deduced otherwise the checks below might cache
5994 // the wrong linkage.
5995 assert(S.ParsingInitForAutoVars.count(&ND) == 0);
5997 // 'weak' only applies to declarations with external linkage.
5998 if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) {
5999 if (!ND.isExternallyVisible()) {
6000 S.Diag(Attr->getLocation(), diag::err_attribute_weak_static);
6001 ND.dropAttr<WeakAttr>();
6004 if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) {
6005 if (ND.isExternallyVisible()) {
6006 S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static);
6007 ND.dropAttr<WeakRefAttr>();
6008 ND.dropAttr<AliasAttr>();
6012 if (auto *VD = dyn_cast<VarDecl>(&ND)) {
6013 if (VD->hasInit()) {
6014 if (const auto *Attr = VD->getAttr<AliasAttr>()) {
6015 assert(VD->isThisDeclarationADefinition() &&
6016 !VD->isExternallyVisible() && "Broken AliasAttr handled late!");
6017 S.Diag(Attr->getLocation(), diag::err_alias_is_definition) << VD << 0;
6018 VD->dropAttr<AliasAttr>();
6023 // 'selectany' only applies to externally visible variable declarations.
6024 // It does not apply to functions.
6025 if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) {
6026 if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) {
6027 S.Diag(Attr->getLocation(),
6028 diag::err_attribute_selectany_non_extern_data);
6029 ND.dropAttr<SelectAnyAttr>();
6033 if (const InheritableAttr *Attr = getDLLAttr(&ND)) {
6034 auto *VD = dyn_cast<VarDecl>(&ND);
6035 bool IsAnonymousNS = false;
6036 bool IsMicrosoft = S.Context.getTargetInfo().getCXXABI().isMicrosoft();
6038 const NamespaceDecl *NS = dyn_cast<NamespaceDecl>(VD->getDeclContext());
6039 while (NS && !IsAnonymousNS) {
6040 IsAnonymousNS = NS->isAnonymousNamespace();
6041 NS = dyn_cast<NamespaceDecl>(NS->getParent());
6044 // dll attributes require external linkage. Static locals may have external
6045 // linkage but still cannot be explicitly imported or exported.
6046 // In Microsoft mode, a variable defined in anonymous namespace must have
6047 // external linkage in order to be exported.
6048 bool AnonNSInMicrosoftMode = IsAnonymousNS && IsMicrosoft;
6049 if ((ND.isExternallyVisible() && AnonNSInMicrosoftMode) ||
6050 (!AnonNSInMicrosoftMode &&
6051 (!ND.isExternallyVisible() || (VD && VD->isStaticLocal())))) {
6052 S.Diag(ND.getLocation(), diag::err_attribute_dll_not_extern)
6054 ND.setInvalidDecl();
6058 // Virtual functions cannot be marked as 'notail'.
6059 if (auto *Attr = ND.getAttr<NotTailCalledAttr>())
6060 if (auto *MD = dyn_cast<CXXMethodDecl>(&ND))
6061 if (MD->isVirtual()) {
6062 S.Diag(ND.getLocation(),
6063 diag::err_invalid_attribute_on_virtual_function)
6065 ND.dropAttr<NotTailCalledAttr>();
6068 // Check the attributes on the function type, if any.
6069 if (const auto *FD = dyn_cast<FunctionDecl>(&ND)) {
6070 // Don't declare this variable in the second operand of the for-statement;
6071 // GCC miscompiles that by ending its lifetime before evaluating the
6072 // third operand. See gcc.gnu.org/PR86769.
6073 AttributedTypeLoc ATL;
6074 for (TypeLoc TL = FD->getTypeSourceInfo()->getTypeLoc();
6075 (ATL = TL.getAsAdjusted<AttributedTypeLoc>());
6076 TL = ATL.getModifiedLoc()) {
6077 // The [[lifetimebound]] attribute can be applied to the implicit object
6078 // parameter of a non-static member function (other than a ctor or dtor)
6079 // by applying it to the function type.
6080 if (const auto *A = ATL.getAttrAs<LifetimeBoundAttr>()) {
6081 const auto *MD = dyn_cast<CXXMethodDecl>(FD);
6082 if (!MD || MD->isStatic()) {
6083 S.Diag(A->getLocation(), diag::err_lifetimebound_no_object_param)
6084 << !MD << A->getRange();
6085 } else if (isa<CXXConstructorDecl>(MD) || isa<CXXDestructorDecl>(MD)) {
6086 S.Diag(A->getLocation(), diag::err_lifetimebound_ctor_dtor)
6087 << isa<CXXDestructorDecl>(MD) << A->getRange();
6094 static void checkDLLAttributeRedeclaration(Sema &S, NamedDecl *OldDecl,
6096 bool IsSpecialization,
6097 bool IsDefinition) {
6098 if (OldDecl->isInvalidDecl() || NewDecl->isInvalidDecl())
6101 bool IsTemplate = false;
6102 if (TemplateDecl *OldTD = dyn_cast<TemplateDecl>(OldDecl)) {
6103 OldDecl = OldTD->getTemplatedDecl();
6105 if (!IsSpecialization)
6106 IsDefinition = false;
6108 if (TemplateDecl *NewTD = dyn_cast<TemplateDecl>(NewDecl)) {
6109 NewDecl = NewTD->getTemplatedDecl();
6113 if (!OldDecl || !NewDecl)
6116 const DLLImportAttr *OldImportAttr = OldDecl->getAttr<DLLImportAttr>();
6117 const DLLExportAttr *OldExportAttr = OldDecl->getAttr<DLLExportAttr>();
6118 const DLLImportAttr *NewImportAttr = NewDecl->getAttr<DLLImportAttr>();
6119 const DLLExportAttr *NewExportAttr = NewDecl->getAttr<DLLExportAttr>();
6121 // dllimport and dllexport are inheritable attributes so we have to exclude
6122 // inherited attribute instances.
6123 bool HasNewAttr = (NewImportAttr && !NewImportAttr->isInherited()) ||
6124 (NewExportAttr && !NewExportAttr->isInherited());
6126 // A redeclaration is not allowed to add a dllimport or dllexport attribute,
6127 // the only exception being explicit specializations.
6128 // Implicitly generated declarations are also excluded for now because there
6129 // is no other way to switch these to use dllimport or dllexport.
6130 bool AddsAttr = !(OldImportAttr || OldExportAttr) && HasNewAttr;
6132 if (AddsAttr && !IsSpecialization && !OldDecl->isImplicit()) {
6133 // Allow with a warning for free functions and global variables.
6134 bool JustWarn = false;
6135 if (!OldDecl->isCXXClassMember()) {
6136 auto *VD = dyn_cast<VarDecl>(OldDecl);
6137 if (VD && !VD->getDescribedVarTemplate())
6139 auto *FD = dyn_cast<FunctionDecl>(OldDecl);
6140 if (FD && FD->getTemplatedKind() == FunctionDecl::TK_NonTemplate)
6144 // We cannot change a declaration that's been used because IR has already
6145 // been emitted. Dllimported functions will still work though (modulo
6146 // address equality) as they can use the thunk.
6147 if (OldDecl->isUsed())
6148 if (!isa<FunctionDecl>(OldDecl) || !NewImportAttr)
6151 unsigned DiagID = JustWarn ? diag::warn_attribute_dll_redeclaration
6152 : diag::err_attribute_dll_redeclaration;
6153 S.Diag(NewDecl->getLocation(), DiagID)
6155 << (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr);
6156 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
6158 NewDecl->setInvalidDecl();
6163 // A redeclaration is not allowed to drop a dllimport attribute, the only
6164 // exceptions being inline function definitions (except for function
6165 // templates), local extern declarations, qualified friend declarations or
6166 // special MSVC extension: in the last case, the declaration is treated as if
6167 // it were marked dllexport.
6168 bool IsInline = false, IsStaticDataMember = false, IsQualifiedFriend = false;
6169 bool IsMicrosoft = S.Context.getTargetInfo().getCXXABI().isMicrosoft();
6170 if (const auto *VD = dyn_cast<VarDecl>(NewDecl)) {
6171 // Ignore static data because out-of-line definitions are diagnosed
6173 IsStaticDataMember = VD->isStaticDataMember();
6174 IsDefinition = VD->isThisDeclarationADefinition(S.Context) !=
6175 VarDecl::DeclarationOnly;
6176 } else if (const auto *FD = dyn_cast<FunctionDecl>(NewDecl)) {
6177 IsInline = FD->isInlined();
6178 IsQualifiedFriend = FD->getQualifier() &&
6179 FD->getFriendObjectKind() == Decl::FOK_Declared;
6182 if (OldImportAttr && !HasNewAttr &&
6183 (!IsInline || (IsMicrosoft && IsTemplate)) && !IsStaticDataMember &&
6184 !NewDecl->isLocalExternDecl() && !IsQualifiedFriend) {
6185 if (IsMicrosoft && IsDefinition) {
6186 S.Diag(NewDecl->getLocation(),
6187 diag::warn_redeclaration_without_import_attribute)
6189 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
6190 NewDecl->dropAttr<DLLImportAttr>();
6191 NewDecl->addAttr(::new (S.Context) DLLExportAttr(
6192 NewImportAttr->getRange(), S.Context,
6193 NewImportAttr->getSpellingListIndex()));
6195 S.Diag(NewDecl->getLocation(),
6196 diag::warn_redeclaration_without_attribute_prev_attribute_ignored)
6197 << NewDecl << OldImportAttr;
6198 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
6199 S.Diag(OldImportAttr->getLocation(), diag::note_previous_attribute);
6200 OldDecl->dropAttr<DLLImportAttr>();
6201 NewDecl->dropAttr<DLLImportAttr>();
6203 } else if (IsInline && OldImportAttr && !IsMicrosoft) {
6204 // In MinGW, seeing a function declared inline drops the dllimport
6206 OldDecl->dropAttr<DLLImportAttr>();
6207 NewDecl->dropAttr<DLLImportAttr>();
6208 S.Diag(NewDecl->getLocation(),
6209 diag::warn_dllimport_dropped_from_inline_function)
6210 << NewDecl << OldImportAttr;
6213 // A specialization of a class template member function is processed here
6214 // since it's a redeclaration. If the parent class is dllexport, the
6215 // specialization inherits that attribute. This doesn't happen automatically
6216 // since the parent class isn't instantiated until later.
6217 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDecl)) {
6218 if (MD->getTemplatedKind() == FunctionDecl::TK_MemberSpecialization &&
6219 !NewImportAttr && !NewExportAttr) {
6220 if (const DLLExportAttr *ParentExportAttr =
6221 MD->getParent()->getAttr<DLLExportAttr>()) {
6222 DLLExportAttr *NewAttr = ParentExportAttr->clone(S.Context);
6223 NewAttr->setInherited(true);
6224 NewDecl->addAttr(NewAttr);
6230 /// Given that we are within the definition of the given function,
6231 /// will that definition behave like C99's 'inline', where the
6232 /// definition is discarded except for optimization purposes?
6233 static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) {
6234 // Try to avoid calling GetGVALinkageForFunction.
6236 // All cases of this require the 'inline' keyword.
6237 if (!FD->isInlined()) return false;
6239 // This is only possible in C++ with the gnu_inline attribute.
6240 if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>())
6243 // Okay, go ahead and call the relatively-more-expensive function.
6244 return S.Context.GetGVALinkageForFunction(FD) == GVA_AvailableExternally;
6247 /// Determine whether a variable is extern "C" prior to attaching
6248 /// an initializer. We can't just call isExternC() here, because that
6249 /// will also compute and cache whether the declaration is externally
6250 /// visible, which might change when we attach the initializer.
6252 /// This can only be used if the declaration is known to not be a
6253 /// redeclaration of an internal linkage declaration.
6259 /// Attaching the initializer here makes this declaration not externally
6260 /// visible, because its type has internal linkage.
6262 /// FIXME: This is a hack.
6263 template<typename T>
6264 static bool isIncompleteDeclExternC(Sema &S, const T *D) {
6265 if (S.getLangOpts().CPlusPlus) {
6266 // In C++, the overloadable attribute negates the effects of extern "C".
6267 if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>())
6270 // So do CUDA's host/device attributes.
6271 if (S.getLangOpts().CUDA && (D->template hasAttr<CUDADeviceAttr>() ||
6272 D->template hasAttr<CUDAHostAttr>()))
6275 return D->isExternC();
6278 static bool shouldConsiderLinkage(const VarDecl *VD) {
6279 const DeclContext *DC = VD->getDeclContext()->getRedeclContext();
6280 if (DC->isFunctionOrMethod() || isa<OMPDeclareReductionDecl>(DC) ||
6281 isa<OMPDeclareMapperDecl>(DC))
6282 return VD->hasExternalStorage();
6283 if (DC->isFileContext())
6287 llvm_unreachable("Unexpected context");
6290 static bool shouldConsiderLinkage(const FunctionDecl *FD) {
6291 const DeclContext *DC = FD->getDeclContext()->getRedeclContext();
6292 if (DC->isFileContext() || DC->isFunctionOrMethod() ||
6293 isa<OMPDeclareReductionDecl>(DC) || isa<OMPDeclareMapperDecl>(DC))
6297 llvm_unreachable("Unexpected context");
6300 static bool hasParsedAttr(Scope *S, const Declarator &PD,
6301 ParsedAttr::Kind Kind) {
6302 // Check decl attributes on the DeclSpec.
6303 if (PD.getDeclSpec().getAttributes().hasAttribute(Kind))
6306 // Walk the declarator structure, checking decl attributes that were in a type
6307 // position to the decl itself.
6308 for (unsigned I = 0, E = PD.getNumTypeObjects(); I != E; ++I) {
6309 if (PD.getTypeObject(I).getAttrs().hasAttribute(Kind))
6313 // Finally, check attributes on the decl itself.
6314 return PD.getAttributes().hasAttribute(Kind);
6317 /// Adjust the \c DeclContext for a function or variable that might be a
6318 /// function-local external declaration.
6319 bool Sema::adjustContextForLocalExternDecl(DeclContext *&DC) {
6320 if (!DC->isFunctionOrMethod())
6323 // If this is a local extern function or variable declared within a function
6324 // template, don't add it into the enclosing namespace scope until it is
6325 // instantiated; it might have a dependent type right now.
6326 if (DC->isDependentContext())
6329 // C++11 [basic.link]p7:
6330 // When a block scope declaration of an entity with linkage is not found to
6331 // refer to some other declaration, then that entity is a member of the
6332 // innermost enclosing namespace.
6334 // Per C++11 [namespace.def]p6, the innermost enclosing namespace is a
6335 // semantically-enclosing namespace, not a lexically-enclosing one.
6336 while (!DC->isFileContext() && !isa<LinkageSpecDecl>(DC))
6337 DC = DC->getParent();
6341 /// Returns true if given declaration has external C language linkage.
6342 static bool isDeclExternC(const Decl *D) {
6343 if (const auto *FD = dyn_cast<FunctionDecl>(D))
6344 return FD->isExternC();
6345 if (const auto *VD = dyn_cast<VarDecl>(D))
6346 return VD->isExternC();
6348 llvm_unreachable("Unknown type of decl!");
6351 NamedDecl *Sema::ActOnVariableDeclarator(
6352 Scope *S, Declarator &D, DeclContext *DC, TypeSourceInfo *TInfo,
6353 LookupResult &Previous, MultiTemplateParamsArg TemplateParamLists,
6354 bool &AddToScope, ArrayRef<BindingDecl *> Bindings) {
6355 QualType R = TInfo->getType();
6356 DeclarationName Name = GetNameForDeclarator(D).getName();
6358 IdentifierInfo *II = Name.getAsIdentifierInfo();
6360 if (D.isDecompositionDeclarator()) {
6361 // Take the name of the first declarator as our name for diagnostic
6363 auto &Decomp = D.getDecompositionDeclarator();
6364 if (!Decomp.bindings().empty()) {
6365 II = Decomp.bindings()[0].Name;
6369 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) << Name;
6373 if (getLangOpts().OpenCL) {
6374 // OpenCL v2.0 s6.9.b - Image type can only be used as a function argument.
6375 // OpenCL v2.0 s6.13.16.1 - Pipe type can only be used as a function
6377 if (R->isImageType() || R->isPipeType()) {
6378 Diag(D.getIdentifierLoc(),
6379 diag::err_opencl_type_can_only_be_used_as_function_parameter)
6385 // OpenCL v1.2 s6.9.r:
6386 // The event type cannot be used to declare a program scope variable.
6387 // OpenCL v2.0 s6.9.q:
6388 // The clk_event_t and reserve_id_t types cannot be declared in program scope.
6389 if (NULL == S->getParent()) {
6390 if (R->isReserveIDT() || R->isClkEventT() || R->isEventT()) {
6391 Diag(D.getIdentifierLoc(),
6392 diag::err_invalid_type_for_program_scope_var) << R;
6398 // OpenCL v1.0 s6.8.a.3: Pointers to functions are not allowed.
6400 while (NR->isPointerType()) {
6401 if (NR->isFunctionPointerType()) {
6402 Diag(D.getIdentifierLoc(), diag::err_opencl_function_pointer);
6406 NR = NR->getPointeeType();
6409 if (!getOpenCLOptions().isEnabled("cl_khr_fp16")) {
6410 // OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and
6411 // half array type (unless the cl_khr_fp16 extension is enabled).
6412 if (Context.getBaseElementType(R)->isHalfType()) {
6413 Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R;
6418 if (R->isSamplerT()) {
6419 // OpenCL v1.2 s6.9.b p4:
6420 // The sampler type cannot be used with the __local and __global address
6421 // space qualifiers.
6422 if (R.getAddressSpace() == LangAS::opencl_local ||
6423 R.getAddressSpace() == LangAS::opencl_global) {
6424 Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace);
6427 // OpenCL v1.2 s6.12.14.1:
6428 // A global sampler must be declared with either the constant address
6429 // space qualifier or with the const qualifier.
6430 if (DC->isTranslationUnit() &&
6431 !(R.getAddressSpace() == LangAS::opencl_constant ||
6432 R.isConstQualified())) {
6433 Diag(D.getIdentifierLoc(), diag::err_opencl_nonconst_global_sampler);
6438 // OpenCL v1.2 s6.9.r:
6439 // The event type cannot be used with the __local, __constant and __global
6440 // address space qualifiers.
6441 if (R->isEventT()) {
6442 if (R.getAddressSpace() != LangAS::opencl_private) {
6443 Diag(D.getBeginLoc(), diag::err_event_t_addr_space_qual);
6448 // C++ for OpenCL does not allow the thread_local storage qualifier.
6449 // OpenCL C does not support thread_local either, and
6450 // also reject all other thread storage class specifiers.
6451 DeclSpec::TSCS TSC = D.getDeclSpec().getThreadStorageClassSpec();
6452 if (TSC != TSCS_unspecified) {
6453 bool IsCXX = getLangOpts().OpenCLCPlusPlus;
6454 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6455 diag::err_opencl_unknown_type_specifier)
6456 << IsCXX << getLangOpts().getOpenCLVersionTuple().getAsString()
6457 << DeclSpec::getSpecifierName(TSC) << 1;
6463 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec();
6464 StorageClass SC = StorageClassSpecToVarDeclStorageClass(D.getDeclSpec());
6466 // dllimport globals without explicit storage class are treated as extern. We
6467 // have to change the storage class this early to get the right DeclContext.
6468 if (SC == SC_None && !DC->isRecord() &&
6469 hasParsedAttr(S, D, ParsedAttr::AT_DLLImport) &&
6470 !hasParsedAttr(S, D, ParsedAttr::AT_DLLExport))
6473 DeclContext *OriginalDC = DC;
6474 bool IsLocalExternDecl = SC == SC_Extern &&
6475 adjustContextForLocalExternDecl(DC);
6477 if (SCSpec == DeclSpec::SCS_mutable) {
6478 // mutable can only appear on non-static class members, so it's always
6480 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember);
6485 if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register &&
6486 !D.getAsmLabel() && !getSourceManager().isInSystemMacro(
6487 D.getDeclSpec().getStorageClassSpecLoc())) {
6488 // In C++11, the 'register' storage class specifier is deprecated.
6489 // Suppress the warning in system macros, it's used in macros in some
6490 // popular C system headers, such as in glibc's htonl() macro.
6491 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6492 getLangOpts().CPlusPlus17 ? diag::ext_register_storage_class
6493 : diag::warn_deprecated_register)
6494 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6497 DiagnoseFunctionSpecifiers(D.getDeclSpec());
6499 if (!DC->isRecord() && S->getFnParent() == nullptr) {
6500 // C99 6.9p2: The storage-class specifiers auto and register shall not
6501 // appear in the declaration specifiers in an external declaration.
6502 // Global Register+Asm is a GNU extension we support.
6503 if (SC == SC_Auto || (SC == SC_Register && !D.getAsmLabel())) {
6504 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope);
6509 bool IsMemberSpecialization = false;
6510 bool IsVariableTemplateSpecialization = false;
6511 bool IsPartialSpecialization = false;
6512 bool IsVariableTemplate = false;
6513 VarDecl *NewVD = nullptr;
6514 VarTemplateDecl *NewTemplate = nullptr;
6515 TemplateParameterList *TemplateParams = nullptr;
6516 if (!getLangOpts().CPlusPlus) {
6517 NewVD = VarDecl::Create(Context, DC, D.getBeginLoc(), D.getIdentifierLoc(),
6520 if (R->getContainedDeducedType())
6521 ParsingInitForAutoVars.insert(NewVD);
6523 if (D.isInvalidType())
6524 NewVD->setInvalidDecl();
6526 if (NewVD->getType().hasNonTrivialToPrimitiveDestructCUnion() &&
6527 NewVD->hasLocalStorage())
6528 checkNonTrivialCUnion(NewVD->getType(), NewVD->getLocation(),
6529 NTCUC_AutoVar, NTCUK_Destruct);
6531 bool Invalid = false;
6533 if (DC->isRecord() && !CurContext->isRecord()) {
6534 // This is an out-of-line definition of a static data member.
6539 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6540 diag::err_static_out_of_line)
6541 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6546 // [dcl.stc] p2: The auto or register specifiers shall be applied only
6547 // to names of variables declared in a block or to function parameters.
6548 // [dcl.stc] p6: The extern specifier cannot be used in the declaration
6551 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6552 diag::err_storage_class_for_static_member)
6553 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6555 case SC_PrivateExtern:
6556 llvm_unreachable("C storage class in c++!");
6560 if (SC == SC_Static && CurContext->isRecord()) {
6561 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) {
6562 if (RD->isLocalClass())
6563 Diag(D.getIdentifierLoc(),
6564 diag::err_static_data_member_not_allowed_in_local_class)
6565 << Name << RD->getDeclName();
6567 // C++98 [class.union]p1: If a union contains a static data member,
6568 // the program is ill-formed. C++11 drops this restriction.
6570 Diag(D.getIdentifierLoc(),
6571 getLangOpts().CPlusPlus11
6572 ? diag::warn_cxx98_compat_static_data_member_in_union
6573 : diag::ext_static_data_member_in_union) << Name;
6574 // We conservatively disallow static data members in anonymous structs.
6575 else if (!RD->getDeclName())
6576 Diag(D.getIdentifierLoc(),
6577 diag::err_static_data_member_not_allowed_in_anon_struct)
6578 << Name << RD->isUnion();
6582 // Match up the template parameter lists with the scope specifier, then
6583 // determine whether we have a template or a template specialization.
6584 TemplateParams = MatchTemplateParametersToScopeSpecifier(
6585 D.getDeclSpec().getBeginLoc(), D.getIdentifierLoc(),
6586 D.getCXXScopeSpec(),
6587 D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId
6588 ? D.getName().TemplateId
6591 /*never a friend*/ false, IsMemberSpecialization, Invalid);
6593 if (TemplateParams) {
6594 if (!TemplateParams->size() &&
6595 D.getName().getKind() != UnqualifiedIdKind::IK_TemplateId) {
6596 // There is an extraneous 'template<>' for this variable. Complain
6597 // about it, but allow the declaration of the variable.
6598 Diag(TemplateParams->getTemplateLoc(),
6599 diag::err_template_variable_noparams)
6601 << SourceRange(TemplateParams->getTemplateLoc(),
6602 TemplateParams->getRAngleLoc());
6603 TemplateParams = nullptr;
6605 if (D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId) {
6606 // This is an explicit specialization or a partial specialization.
6607 // FIXME: Check that we can declare a specialization here.
6608 IsVariableTemplateSpecialization = true;
6609 IsPartialSpecialization = TemplateParams->size() > 0;
6610 } else { // if (TemplateParams->size() > 0)
6611 // This is a template declaration.
6612 IsVariableTemplate = true;
6614 // Check that we can declare a template here.
6615 if (CheckTemplateDeclScope(S, TemplateParams))
6618 // Only C++1y supports variable templates (N3651).
6619 Diag(D.getIdentifierLoc(),
6620 getLangOpts().CPlusPlus14
6621 ? diag::warn_cxx11_compat_variable_template
6622 : diag::ext_variable_template);
6627 D.getName().getKind() != UnqualifiedIdKind::IK_TemplateId) &&
6628 "should have a 'template<>' for this decl");
6631 if (IsVariableTemplateSpecialization) {
6632 SourceLocation TemplateKWLoc =
6633 TemplateParamLists.size() > 0
6634 ? TemplateParamLists[0]->getTemplateLoc()
6636 DeclResult Res = ActOnVarTemplateSpecialization(
6637 S, D, TInfo, TemplateKWLoc, TemplateParams, SC,
6638 IsPartialSpecialization);
6639 if (Res.isInvalid())
6641 NewVD = cast<VarDecl>(Res.get());
6643 } else if (D.isDecompositionDeclarator()) {
6644 NewVD = DecompositionDecl::Create(Context, DC, D.getBeginLoc(),
6645 D.getIdentifierLoc(), R, TInfo, SC,
6648 NewVD = VarDecl::Create(Context, DC, D.getBeginLoc(),
6649 D.getIdentifierLoc(), II, R, TInfo, SC);
6651 // If this is supposed to be a variable template, create it as such.
6652 if (IsVariableTemplate) {
6654 VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name,
6655 TemplateParams, NewVD);
6656 NewVD->setDescribedVarTemplate(NewTemplate);
6659 // If this decl has an auto type in need of deduction, make a note of the
6660 // Decl so we can diagnose uses of it in its own initializer.
6661 if (R->getContainedDeducedType())
6662 ParsingInitForAutoVars.insert(NewVD);
6664 if (D.isInvalidType() || Invalid) {
6665 NewVD->setInvalidDecl();
6667 NewTemplate->setInvalidDecl();
6670 SetNestedNameSpecifier(*this, NewVD, D);
6672 // If we have any template parameter lists that don't directly belong to
6673 // the variable (matching the scope specifier), store them.
6674 unsigned VDTemplateParamLists = TemplateParams ? 1 : 0;
6675 if (TemplateParamLists.size() > VDTemplateParamLists)
6676 NewVD->setTemplateParameterListsInfo(
6677 Context, TemplateParamLists.drop_back(VDTemplateParamLists));
6679 if (D.getDeclSpec().hasConstexprSpecifier()) {
6680 NewVD->setConstexpr(true);
6681 // C++1z [dcl.spec.constexpr]p1:
6682 // A static data member declared with the constexpr specifier is
6683 // implicitly an inline variable.
6684 if (NewVD->isStaticDataMember() && getLangOpts().CPlusPlus17)
6685 NewVD->setImplicitlyInline();
6686 if (D.getDeclSpec().getConstexprSpecifier() == CSK_consteval)
6687 Diag(D.getDeclSpec().getConstexprSpecLoc(),
6688 diag::err_constexpr_wrong_decl_kind)
6693 if (D.getDeclSpec().isInlineSpecified()) {
6694 if (!getLangOpts().CPlusPlus) {
6695 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
6697 } else if (CurContext->isFunctionOrMethod()) {
6698 // 'inline' is not allowed on block scope variable declaration.
6699 Diag(D.getDeclSpec().getInlineSpecLoc(),
6700 diag::err_inline_declaration_block_scope) << Name
6701 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
6703 Diag(D.getDeclSpec().getInlineSpecLoc(),
6704 getLangOpts().CPlusPlus17 ? diag::warn_cxx14_compat_inline_variable
6705 : diag::ext_inline_variable);
6706 NewVD->setInlineSpecified();
6710 // Set the lexical context. If the declarator has a C++ scope specifier, the
6711 // lexical context will be different from the semantic context.
6712 NewVD->setLexicalDeclContext(CurContext);
6714 NewTemplate->setLexicalDeclContext(CurContext);
6716 if (IsLocalExternDecl) {
6717 if (D.isDecompositionDeclarator())
6718 for (auto *B : Bindings)
6719 B->setLocalExternDecl();
6721 NewVD->setLocalExternDecl();
6724 bool EmitTLSUnsupportedError = false;
6725 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) {
6726 // C++11 [dcl.stc]p4:
6727 // When thread_local is applied to a variable of block scope the
6728 // storage-class-specifier static is implied if it does not appear
6730 // Core issue: 'static' is not implied if the variable is declared
6732 if (NewVD->hasLocalStorage() &&
6733 (SCSpec != DeclSpec::SCS_unspecified ||
6734 TSCS != DeclSpec::TSCS_thread_local ||
6735 !DC->isFunctionOrMethod()))
6736 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6737 diag::err_thread_non_global)
6738 << DeclSpec::getSpecifierName(TSCS);
6739 else if (!Context.getTargetInfo().isTLSSupported()) {
6740 if (getLangOpts().CUDA || getLangOpts().OpenMPIsDevice) {
6741 // Postpone error emission until we've collected attributes required to
6742 // figure out whether it's a host or device variable and whether the
6743 // error should be ignored.
6744 EmitTLSUnsupportedError = true;
6745 // We still need to mark the variable as TLS so it shows up in AST with
6746 // proper storage class for other tools to use even if we're not going
6747 // to emit any code for it.
6748 NewVD->setTSCSpec(TSCS);
6750 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6751 diag::err_thread_unsupported);
6753 NewVD->setTSCSpec(TSCS);
6757 // An inline definition of a function with external linkage shall
6758 // not contain a definition of a modifiable object with static or
6759 // thread storage duration...
6760 // We only apply this when the function is required to be defined
6761 // elsewhere, i.e. when the function is not 'extern inline'. Note
6762 // that a local variable with thread storage duration still has to
6763 // be marked 'static'. Also note that it's possible to get these
6764 // semantics in C++ using __attribute__((gnu_inline)).
6765 if (SC == SC_Static && S->getFnParent() != nullptr &&
6766 !NewVD->getType().isConstQualified()) {
6767 FunctionDecl *CurFD = getCurFunctionDecl();
6768 if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) {
6769 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6770 diag::warn_static_local_in_extern_inline);
6771 MaybeSuggestAddingStaticToDecl(CurFD);
6775 if (D.getDeclSpec().isModulePrivateSpecified()) {
6776 if (IsVariableTemplateSpecialization)
6777 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6778 << (IsPartialSpecialization ? 1 : 0)
6779 << FixItHint::CreateRemoval(
6780 D.getDeclSpec().getModulePrivateSpecLoc());
6781 else if (IsMemberSpecialization)
6782 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6784 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6785 else if (NewVD->hasLocalStorage())
6786 Diag(NewVD->getLocation(), diag::err_module_private_local)
6787 << 0 << NewVD->getDeclName()
6788 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
6789 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6791 NewVD->setModulePrivate();
6793 NewTemplate->setModulePrivate();
6794 for (auto *B : Bindings)
6795 B->setModulePrivate();
6799 // Handle attributes prior to checking for duplicates in MergeVarDecl
6800 ProcessDeclAttributes(S, NewVD, D);
6802 if (getLangOpts().CUDA || getLangOpts().OpenMPIsDevice) {
6803 if (EmitTLSUnsupportedError &&
6804 ((getLangOpts().CUDA && DeclAttrsMatchCUDAMode(getLangOpts(), NewVD)) ||
6805 (getLangOpts().OpenMPIsDevice &&
6806 NewVD->hasAttr<OMPDeclareTargetDeclAttr>())))
6807 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6808 diag::err_thread_unsupported);
6809 // CUDA B.2.5: "__shared__ and __constant__ variables have implied static
6810 // storage [duration]."
6811 if (SC == SC_None && S->getFnParent() != nullptr &&
6812 (NewVD->hasAttr<CUDASharedAttr>() ||
6813 NewVD->hasAttr<CUDAConstantAttr>())) {
6814 NewVD->setStorageClass(SC_Static);
6818 // Ensure that dllimport globals without explicit storage class are treated as
6819 // extern. The storage class is set above using parsed attributes. Now we can
6820 // check the VarDecl itself.
6821 assert(!NewVD->hasAttr<DLLImportAttr>() ||
6822 NewVD->getAttr<DLLImportAttr>()->isInherited() ||
6823 NewVD->isStaticDataMember() || NewVD->getStorageClass() != SC_None);
6825 // In auto-retain/release, infer strong retension for variables of
6827 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD))
6828 NewVD->setInvalidDecl();
6830 // Handle GNU asm-label extension (encoded as an attribute).
6831 if (Expr *E = (Expr*)D.getAsmLabel()) {
6832 // The parser guarantees this is a string.
6833 StringLiteral *SE = cast<StringLiteral>(E);
6834 StringRef Label = SE->getString();
6835 if (S->getFnParent() != nullptr) {
6839 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label;
6842 // Local Named register
6843 if (!Context.getTargetInfo().isValidGCCRegisterName(Label) &&
6844 DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl()))
6845 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6849 case SC_PrivateExtern:
6852 } else if (SC == SC_Register) {
6853 // Global Named register
6854 if (DeclAttrsMatchCUDAMode(getLangOpts(), NewVD)) {
6855 const auto &TI = Context.getTargetInfo();
6856 bool HasSizeMismatch;
6858 if (!TI.isValidGCCRegisterName(Label))
6859 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6860 else if (!TI.validateGlobalRegisterVariable(Label,
6861 Context.getTypeSize(R),
6863 Diag(E->getExprLoc(), diag::err_asm_invalid_global_var_reg) << Label;
6864 else if (HasSizeMismatch)
6865 Diag(E->getExprLoc(), diag::err_asm_register_size_mismatch) << Label;
6868 if (!R->isIntegralType(Context) && !R->isPointerType()) {
6869 Diag(D.getBeginLoc(), diag::err_asm_bad_register_type);
6870 NewVD->setInvalidDecl(true);
6874 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0),
6875 Context, Label, 0));
6876 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
6877 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
6878 ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier());
6879 if (I != ExtnameUndeclaredIdentifiers.end()) {
6880 if (isDeclExternC(NewVD)) {
6881 NewVD->addAttr(I->second);
6882 ExtnameUndeclaredIdentifiers.erase(I);
6884 Diag(NewVD->getLocation(), diag::warn_redefine_extname_not_applied)
6885 << /*Variable*/1 << NewVD;
6889 // Find the shadowed declaration before filtering for scope.
6890 NamedDecl *ShadowedDecl = D.getCXXScopeSpec().isEmpty()
6891 ? getShadowedDeclaration(NewVD, Previous)
6894 // Don't consider existing declarations that are in a different
6895 // scope and are out-of-semantic-context declarations (if the new
6896 // declaration has linkage).
6897 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewVD),
6898 D.getCXXScopeSpec().isNotEmpty() ||
6899 IsMemberSpecialization ||
6900 IsVariableTemplateSpecialization);
6902 // Check whether the previous declaration is in the same block scope. This
6903 // affects whether we merge types with it, per C++11 [dcl.array]p3.
6904 if (getLangOpts().CPlusPlus &&
6905 NewVD->isLocalVarDecl() && NewVD->hasExternalStorage())
6906 NewVD->setPreviousDeclInSameBlockScope(
6907 Previous.isSingleResult() && !Previous.isShadowed() &&
6908 isDeclInScope(Previous.getFoundDecl(), OriginalDC, S, false));
6910 if (!getLangOpts().CPlusPlus) {
6911 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6913 // If this is an explicit specialization of a static data member, check it.
6914 if (IsMemberSpecialization && !NewVD->isInvalidDecl() &&
6915 CheckMemberSpecialization(NewVD, Previous))
6916 NewVD->setInvalidDecl();
6918 // Merge the decl with the existing one if appropriate.
6919 if (!Previous.empty()) {
6920 if (Previous.isSingleResult() &&
6921 isa<FieldDecl>(Previous.getFoundDecl()) &&
6922 D.getCXXScopeSpec().isSet()) {
6923 // The user tried to define a non-static data member
6924 // out-of-line (C++ [dcl.meaning]p1).
6925 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line)
6926 << D.getCXXScopeSpec().getRange();
6928 NewVD->setInvalidDecl();
6930 } else if (D.getCXXScopeSpec().isSet()) {
6931 // No previous declaration in the qualifying scope.
6932 Diag(D.getIdentifierLoc(), diag::err_no_member)
6933 << Name << computeDeclContext(D.getCXXScopeSpec(), true)
6934 << D.getCXXScopeSpec().getRange();
6935 NewVD->setInvalidDecl();
6938 if (!IsVariableTemplateSpecialization)
6939 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6942 VarTemplateDecl *PrevVarTemplate =
6943 NewVD->getPreviousDecl()
6944 ? NewVD->getPreviousDecl()->getDescribedVarTemplate()
6947 // Check the template parameter list of this declaration, possibly
6948 // merging in the template parameter list from the previous variable
6949 // template declaration.
6950 if (CheckTemplateParameterList(
6952 PrevVarTemplate ? PrevVarTemplate->getTemplateParameters()
6954 (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() &&
6955 DC->isDependentContext())
6956 ? TPC_ClassTemplateMember
6958 NewVD->setInvalidDecl();
6960 // If we are providing an explicit specialization of a static variable
6961 // template, make a note of that.
6962 if (PrevVarTemplate &&
6963 PrevVarTemplate->getInstantiatedFromMemberTemplate())
6964 PrevVarTemplate->setMemberSpecialization();
6968 // Diagnose shadowed variables iff this isn't a redeclaration.
6969 if (ShadowedDecl && !D.isRedeclaration())
6970 CheckShadow(NewVD, ShadowedDecl, Previous);
6972 ProcessPragmaWeak(S, NewVD);
6974 // If this is the first declaration of an extern C variable, update
6975 // the map of such variables.
6976 if (NewVD->isFirstDecl() && !NewVD->isInvalidDecl() &&
6977 isIncompleteDeclExternC(*this, NewVD))
6978 RegisterLocallyScopedExternCDecl(NewVD, S);
6980 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
6981 Decl *ManglingContextDecl;
6982 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
6983 NewVD->getDeclContext(), ManglingContextDecl)) {
6984 Context.setManglingNumber(
6985 NewVD, MCtx->getManglingNumber(
6986 NewVD, getMSManglingNumber(getLangOpts(), S)));
6987 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
6991 // Special handling of variable named 'main'.
6992 if (Name.getAsIdentifierInfo() && Name.getAsIdentifierInfo()->isStr("main") &&
6993 NewVD->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
6994 !getLangOpts().Freestanding && !NewVD->getDescribedVarTemplate()) {
6996 // C++ [basic.start.main]p3
6997 // A program that declares a variable main at global scope is ill-formed.
6998 if (getLangOpts().CPlusPlus)
6999 Diag(D.getBeginLoc(), diag::err_main_global_variable);
7001 // In C, and external-linkage variable named main results in undefined
7003 else if (NewVD->hasExternalFormalLinkage())
7004 Diag(D.getBeginLoc(), diag::warn_main_redefined);
7007 if (D.isRedeclaration() && !Previous.empty()) {
7008 NamedDecl *Prev = Previous.getRepresentativeDecl();
7009 checkDLLAttributeRedeclaration(*this, Prev, NewVD, IsMemberSpecialization,
7010 D.isFunctionDefinition());
7014 if (NewVD->isInvalidDecl())
7015 NewTemplate->setInvalidDecl();
7016 ActOnDocumentableDecl(NewTemplate);
7020 if (IsMemberSpecialization && !NewVD->isInvalidDecl())
7021 CompleteMemberSpecialization(NewVD, Previous);
7026 /// Enum describing the %select options in diag::warn_decl_shadow.
7027 enum ShadowedDeclKind {
7036 /// Determine what kind of declaration we're shadowing.
7037 static ShadowedDeclKind computeShadowedDeclKind(const NamedDecl *ShadowedDecl,
7038 const DeclContext *OldDC) {
7039 if (isa<TypeAliasDecl>(ShadowedDecl))
7041 else if (isa<TypedefDecl>(ShadowedDecl))
7043 else if (isa<RecordDecl>(OldDC))
7044 return isa<FieldDecl>(ShadowedDecl) ? SDK_Field : SDK_StaticMember;
7046 return OldDC->isFileContext() ? SDK_Global : SDK_Local;
7049 /// Return the location of the capture if the given lambda captures the given
7050 /// variable \p VD, or an invalid source location otherwise.
7051 static SourceLocation getCaptureLocation(const LambdaScopeInfo *LSI,
7052 const VarDecl *VD) {
7053 for (const Capture &Capture : LSI->Captures) {
7054 if (Capture.isVariableCapture() && Capture.getVariable() == VD)
7055 return Capture.getLocation();
7057 return SourceLocation();
7060 static bool shouldWarnIfShadowedDecl(const DiagnosticsEngine &Diags,
7061 const LookupResult &R) {
7062 // Only diagnose if we're shadowing an unambiguous field or variable.
7063 if (R.getResultKind() != LookupResult::Found)
7066 // Return false if warning is ignored.
7067 return !Diags.isIgnored(diag::warn_decl_shadow, R.getNameLoc());
7070 /// Return the declaration shadowed by the given variable \p D, or null
7071 /// if it doesn't shadow any declaration or shadowing warnings are disabled.
7072 NamedDecl *Sema::getShadowedDeclaration(const VarDecl *D,
7073 const LookupResult &R) {
7074 if (!shouldWarnIfShadowedDecl(Diags, R))
7077 // Don't diagnose declarations at file scope.
7078 if (D->hasGlobalStorage())
7081 NamedDecl *ShadowedDecl = R.getFoundDecl();
7082 return isa<VarDecl>(ShadowedDecl) || isa<FieldDecl>(ShadowedDecl)
7087 /// Return the declaration shadowed by the given typedef \p D, or null
7088 /// if it doesn't shadow any declaration or shadowing warnings are disabled.
7089 NamedDecl *Sema::getShadowedDeclaration(const TypedefNameDecl *D,
7090 const LookupResult &R) {
7091 // Don't warn if typedef declaration is part of a class
7092 if (D->getDeclContext()->isRecord())
7095 if (!shouldWarnIfShadowedDecl(Diags, R))
7098 NamedDecl *ShadowedDecl = R.getFoundDecl();
7099 return isa<TypedefNameDecl>(ShadowedDecl) ? ShadowedDecl : nullptr;
7102 /// Diagnose variable or built-in function shadowing. Implements
7105 /// This method is called whenever a VarDecl is added to a "useful"
7108 /// \param ShadowedDecl the declaration that is shadowed by the given variable
7109 /// \param R the lookup of the name
7111 void Sema::CheckShadow(NamedDecl *D, NamedDecl *ShadowedDecl,
7112 const LookupResult &R) {
7113 DeclContext *NewDC = D->getDeclContext();
7115 if (FieldDecl *FD = dyn_cast<FieldDecl>(ShadowedDecl)) {
7116 // Fields are not shadowed by variables in C++ static methods.
7117 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC))
7121 // Fields shadowed by constructor parameters are a special case. Usually
7122 // the constructor initializes the field with the parameter.
7123 if (isa<CXXConstructorDecl>(NewDC))
7124 if (const auto PVD = dyn_cast<ParmVarDecl>(D)) {
7125 // Remember that this was shadowed so we can either warn about its
7126 // modification or its existence depending on warning settings.
7127 ShadowingDecls.insert({PVD->getCanonicalDecl(), FD});
7132 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl))
7133 if (shadowedVar->isExternC()) {
7134 // For shadowing external vars, make sure that we point to the global
7135 // declaration, not a locally scoped extern declaration.
7136 for (auto I : shadowedVar->redecls())
7137 if (I->isFileVarDecl()) {
7143 DeclContext *OldDC = ShadowedDecl->getDeclContext()->getRedeclContext();
7145 unsigned WarningDiag = diag::warn_decl_shadow;
7146 SourceLocation CaptureLoc;
7147 if (isa<VarDecl>(D) && isa<VarDecl>(ShadowedDecl) && NewDC &&
7148 isa<CXXMethodDecl>(NewDC)) {
7149 if (const auto *RD = dyn_cast<CXXRecordDecl>(NewDC->getParent())) {
7150 if (RD->isLambda() && OldDC->Encloses(NewDC->getLexicalParent())) {
7151 if (RD->getLambdaCaptureDefault() == LCD_None) {
7152 // Try to avoid warnings for lambdas with an explicit capture list.
7153 const auto *LSI = cast<LambdaScopeInfo>(getCurFunction());
7154 // Warn only when the lambda captures the shadowed decl explicitly.
7155 CaptureLoc = getCaptureLocation(LSI, cast<VarDecl>(ShadowedDecl));
7156 if (CaptureLoc.isInvalid())
7157 WarningDiag = diag::warn_decl_shadow_uncaptured_local;
7159 // Remember that this was shadowed so we can avoid the warning if the
7160 // shadowed decl isn't captured and the warning settings allow it.
7161 cast<LambdaScopeInfo>(getCurFunction())
7162 ->ShadowingDecls.push_back(
7163 {cast<VarDecl>(D), cast<VarDecl>(ShadowedDecl)});
7168 if (cast<VarDecl>(ShadowedDecl)->hasLocalStorage()) {
7169 // A variable can't shadow a local variable in an enclosing scope, if
7170 // they are separated by a non-capturing declaration context.
7171 for (DeclContext *ParentDC = NewDC;
7172 ParentDC && !ParentDC->Equals(OldDC);
7173 ParentDC = getLambdaAwareParentOfDeclContext(ParentDC)) {
7174 // Only block literals, captured statements, and lambda expressions
7175 // can capture; other scopes don't.
7176 if (!isa<BlockDecl>(ParentDC) && !isa<CapturedDecl>(ParentDC) &&
7177 !isLambdaCallOperator(ParentDC)) {
7185 // Only warn about certain kinds of shadowing for class members.
7186 if (NewDC && NewDC->isRecord()) {
7187 // In particular, don't warn about shadowing non-class members.
7188 if (!OldDC->isRecord())
7191 // TODO: should we warn about static data members shadowing
7192 // static data members from base classes?
7194 // TODO: don't diagnose for inaccessible shadowed members.
7195 // This is hard to do perfectly because we might friend the
7196 // shadowing context, but that's just a false negative.
7200 DeclarationName Name = R.getLookupName();
7202 // Emit warning and note.
7203 if (getSourceManager().isInSystemMacro(R.getNameLoc()))
7205 ShadowedDeclKind Kind = computeShadowedDeclKind(ShadowedDecl, OldDC);
7206 Diag(R.getNameLoc(), WarningDiag) << Name << Kind << OldDC;
7207 if (!CaptureLoc.isInvalid())
7208 Diag(CaptureLoc, diag::note_var_explicitly_captured_here)
7209 << Name << /*explicitly*/ 1;
7210 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
7213 /// Diagnose shadowing for variables shadowed in the lambda record \p LambdaRD
7214 /// when these variables are captured by the lambda.
7215 void Sema::DiagnoseShadowingLambdaDecls(const LambdaScopeInfo *LSI) {
7216 for (const auto &Shadow : LSI->ShadowingDecls) {
7217 const VarDecl *ShadowedDecl = Shadow.ShadowedDecl;
7218 // Try to avoid the warning when the shadowed decl isn't captured.
7219 SourceLocation CaptureLoc = getCaptureLocation(LSI, ShadowedDecl);
7220 const DeclContext *OldDC = ShadowedDecl->getDeclContext();
7221 Diag(Shadow.VD->getLocation(), CaptureLoc.isInvalid()
7222 ? diag::warn_decl_shadow_uncaptured_local
7223 : diag::warn_decl_shadow)
7224 << Shadow.VD->getDeclName()
7225 << computeShadowedDeclKind(ShadowedDecl, OldDC) << OldDC;
7226 if (!CaptureLoc.isInvalid())
7227 Diag(CaptureLoc, diag::note_var_explicitly_captured_here)
7228 << Shadow.VD->getDeclName() << /*explicitly*/ 0;
7229 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
7233 /// Check -Wshadow without the advantage of a previous lookup.
7234 void Sema::CheckShadow(Scope *S, VarDecl *D) {
7235 if (Diags.isIgnored(diag::warn_decl_shadow, D->getLocation()))
7238 LookupResult R(*this, D->getDeclName(), D->getLocation(),
7239 Sema::LookupOrdinaryName, Sema::ForVisibleRedeclaration);
7241 if (NamedDecl *ShadowedDecl = getShadowedDeclaration(D, R))
7242 CheckShadow(D, ShadowedDecl, R);
7245 /// Check if 'E', which is an expression that is about to be modified, refers
7246 /// to a constructor parameter that shadows a field.
7247 void Sema::CheckShadowingDeclModification(Expr *E, SourceLocation Loc) {
7248 // Quickly ignore expressions that can't be shadowing ctor parameters.
7249 if (!getLangOpts().CPlusPlus || ShadowingDecls.empty())
7251 E = E->IgnoreParenImpCasts();
7252 auto *DRE = dyn_cast<DeclRefExpr>(E);
7255 const NamedDecl *D = cast<NamedDecl>(DRE->getDecl()->getCanonicalDecl());
7256 auto I = ShadowingDecls.find(D);
7257 if (I == ShadowingDecls.end())
7259 const NamedDecl *ShadowedDecl = I->second;
7260 const DeclContext *OldDC = ShadowedDecl->getDeclContext();
7261 Diag(Loc, diag::warn_modifying_shadowing_decl) << D << OldDC;
7262 Diag(D->getLocation(), diag::note_var_declared_here) << D;
7263 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
7265 // Avoid issuing multiple warnings about the same decl.
7266 ShadowingDecls.erase(I);
7269 /// Check for conflict between this global or extern "C" declaration and
7270 /// previous global or extern "C" declarations. This is only used in C++.
7271 template<typename T>
7272 static bool checkGlobalOrExternCConflict(
7273 Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) {
7274 assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\"");
7275 NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName());
7277 if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) {
7278 // The common case: this global doesn't conflict with any extern "C"
7284 if (!IsGlobal || isIncompleteDeclExternC(S, ND)) {
7285 // Both the old and new declarations have C language linkage. This is a
7288 Previous.addDecl(Prev);
7292 // This is a global, non-extern "C" declaration, and there is a previous
7293 // non-global extern "C" declaration. Diagnose if this is a variable
7295 if (!isa<VarDecl>(ND))
7298 // The declaration is extern "C". Check for any declaration in the
7299 // translation unit which might conflict.
7301 // We have already performed the lookup into the translation unit.
7303 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
7305 if (isa<VarDecl>(*I)) {
7311 DeclContext::lookup_result R =
7312 S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName());
7313 for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end();
7315 if (isa<VarDecl>(*I)) {
7319 // FIXME: If we have any other entity with this name in global scope,
7320 // the declaration is ill-formed, but that is a defect: it breaks the
7321 // 'stat' hack, for instance. Only variables can have mangled name
7322 // clashes with extern "C" declarations, so only they deserve a
7331 // Use the first declaration's location to ensure we point at something which
7332 // is lexically inside an extern "C" linkage-spec.
7333 assert(Prev && "should have found a previous declaration to diagnose");
7334 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev))
7335 Prev = FD->getFirstDecl();
7337 Prev = cast<VarDecl>(Prev)->getFirstDecl();
7339 S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict)
7341 S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict)
7346 /// Apply special rules for handling extern "C" declarations. Returns \c true
7347 /// if we have found that this is a redeclaration of some prior entity.
7349 /// Per C++ [dcl.link]p6:
7350 /// Two declarations [for a function or variable] with C language linkage
7351 /// with the same name that appear in different scopes refer to the same
7352 /// [entity]. An entity with C language linkage shall not be declared with
7353 /// the same name as an entity in global scope.
7354 template<typename T>
7355 static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND,
7356 LookupResult &Previous) {
7357 if (!S.getLangOpts().CPlusPlus) {
7358 // In C, when declaring a global variable, look for a corresponding 'extern'
7359 // variable declared in function scope. We don't need this in C++, because
7360 // we find local extern decls in the surrounding file-scope DeclContext.
7361 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
7362 if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) {
7364 Previous.addDecl(Prev);
7371 // A declaration in the translation unit can conflict with an extern "C"
7373 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit())
7374 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous);
7376 // An extern "C" declaration can conflict with a declaration in the
7377 // translation unit or can be a redeclaration of an extern "C" declaration
7378 // in another scope.
7379 if (isIncompleteDeclExternC(S,ND))
7380 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous);
7382 // Neither global nor extern "C": nothing to do.
7386 void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
7387 // If the decl is already known invalid, don't check it.
7388 if (NewVD->isInvalidDecl())
7391 QualType T = NewVD->getType();
7393 // Defer checking an 'auto' type until its initializer is attached.
7394 if (T->isUndeducedType())
7397 if (NewVD->hasAttrs())
7398 CheckAlignasUnderalignment(NewVD);
7400 if (T->isObjCObjectType()) {
7401 Diag(NewVD->getLocation(), diag::err_statically_allocated_object)
7402 << FixItHint::CreateInsertion(NewVD->getLocation(), "*");
7403 T = Context.getObjCObjectPointerType(T);
7407 // Emit an error if an address space was applied to decl with local storage.
7408 // This includes arrays of objects with address space qualifiers, but not
7409 // automatic variables that point to other address spaces.
7410 // ISO/IEC TR 18037 S5.1.2
7411 if (!getLangOpts().OpenCL && NewVD->hasLocalStorage() &&
7412 T.getAddressSpace() != LangAS::Default) {
7413 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl) << 0;
7414 NewVD->setInvalidDecl();
7418 // OpenCL v1.2 s6.8 - The static qualifier is valid only in program
7420 if (getLangOpts().OpenCLVersion == 120 &&
7421 !getOpenCLOptions().isEnabled("cl_clang_storage_class_specifiers") &&
7422 NewVD->isStaticLocal()) {
7423 Diag(NewVD->getLocation(), diag::err_static_function_scope);
7424 NewVD->setInvalidDecl();
7428 if (getLangOpts().OpenCL) {
7429 // OpenCL v2.0 s6.12.5 - The __block storage type is not supported.
7430 if (NewVD->hasAttr<BlocksAttr>()) {
7431 Diag(NewVD->getLocation(), diag::err_opencl_block_storage_type);
7435 if (T->isBlockPointerType()) {
7436 // OpenCL v2.0 s6.12.5 - Any block declaration must be const qualified and
7437 // can't use 'extern' storage class.
7438 if (!T.isConstQualified()) {
7439 Diag(NewVD->getLocation(), diag::err_opencl_invalid_block_declaration)
7441 NewVD->setInvalidDecl();
7444 if (NewVD->hasExternalStorage()) {
7445 Diag(NewVD->getLocation(), diag::err_opencl_extern_block_declaration);
7446 NewVD->setInvalidDecl();
7450 // OpenCL C v1.2 s6.5 - All program scope variables must be declared in the
7451 // __constant address space.
7452 // OpenCL C v2.0 s6.5.1 - Variables defined at program scope and static
7453 // variables inside a function can also be declared in the global
7455 // C++ for OpenCL inherits rule from OpenCL C v2.0.
7456 // FIXME: Adding local AS in C++ for OpenCL might make sense.
7457 if (NewVD->isFileVarDecl() || NewVD->isStaticLocal() ||
7458 NewVD->hasExternalStorage()) {
7459 if (!T->isSamplerT() &&
7460 !(T.getAddressSpace() == LangAS::opencl_constant ||
7461 (T.getAddressSpace() == LangAS::opencl_global &&
7462 (getLangOpts().OpenCLVersion == 200 ||
7463 getLangOpts().OpenCLCPlusPlus)))) {
7464 int Scope = NewVD->isStaticLocal() | NewVD->hasExternalStorage() << 1;
7465 if (getLangOpts().OpenCLVersion == 200 || getLangOpts().OpenCLCPlusPlus)
7466 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
7467 << Scope << "global or constant";
7469 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
7470 << Scope << "constant";
7471 NewVD->setInvalidDecl();
7475 if (T.getAddressSpace() == LangAS::opencl_global) {
7476 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
7477 << 1 /*is any function*/ << "global";
7478 NewVD->setInvalidDecl();
7481 if (T.getAddressSpace() == LangAS::opencl_constant ||
7482 T.getAddressSpace() == LangAS::opencl_local) {
7483 FunctionDecl *FD = getCurFunctionDecl();
7484 // OpenCL v1.1 s6.5.2 and s6.5.3: no local or constant variables
7486 if (FD && !FD->hasAttr<OpenCLKernelAttr>()) {
7487 if (T.getAddressSpace() == LangAS::opencl_constant)
7488 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
7489 << 0 /*non-kernel only*/ << "constant";
7491 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
7492 << 0 /*non-kernel only*/ << "local";
7493 NewVD->setInvalidDecl();
7496 // OpenCL v2.0 s6.5.2 and s6.5.3: local and constant variables must be
7497 // in the outermost scope of a kernel function.
7498 if (FD && FD->hasAttr<OpenCLKernelAttr>()) {
7499 if (!getCurScope()->isFunctionScope()) {
7500 if (T.getAddressSpace() == LangAS::opencl_constant)
7501 Diag(NewVD->getLocation(), diag::err_opencl_addrspace_scope)
7504 Diag(NewVD->getLocation(), diag::err_opencl_addrspace_scope)
7506 NewVD->setInvalidDecl();
7510 } else if (T.getAddressSpace() != LangAS::opencl_private &&
7511 // If we are parsing a template we didn't deduce an addr
7513 T.getAddressSpace() != LangAS::Default) {
7514 // Do not allow other address spaces on automatic variable.
7515 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl) << 1;
7516 NewVD->setInvalidDecl();
7522 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()
7523 && !NewVD->hasAttr<BlocksAttr>()) {
7524 if (getLangOpts().getGC() != LangOptions::NonGC)
7525 Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local);
7527 assert(!getLangOpts().ObjCAutoRefCount);
7528 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
7532 bool isVM = T->isVariablyModifiedType();
7533 if (isVM || NewVD->hasAttr<CleanupAttr>() ||
7534 NewVD->hasAttr<BlocksAttr>())
7535 setFunctionHasBranchProtectedScope();
7537 if ((isVM && NewVD->hasLinkage()) ||
7538 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) {
7539 bool SizeIsNegative;
7540 llvm::APSInt Oversized;
7541 TypeSourceInfo *FixedTInfo = TryToFixInvalidVariablyModifiedTypeSourceInfo(
7542 NewVD->getTypeSourceInfo(), Context, SizeIsNegative, Oversized);
7544 if (FixedTInfo && T == NewVD->getTypeSourceInfo()->getType())
7545 FixedT = FixedTInfo->getType();
7546 else if (FixedTInfo) {
7547 // Type and type-as-written are canonically different. We need to fix up
7548 // both types separately.
7549 FixedT = TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative,
7552 if ((!FixedTInfo || FixedT.isNull()) && T->isVariableArrayType()) {
7553 const VariableArrayType *VAT = Context.getAsVariableArrayType(T);
7554 // FIXME: This won't give the correct result for
7556 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange();
7558 if (NewVD->isFileVarDecl())
7559 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope)
7561 else if (NewVD->isStaticLocal())
7562 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage)
7565 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage)
7567 NewVD->setInvalidDecl();
7572 if (NewVD->isFileVarDecl())
7573 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope);
7575 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage);
7576 NewVD->setInvalidDecl();
7580 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size);
7581 NewVD->setType(FixedT);
7582 NewVD->setTypeSourceInfo(FixedTInfo);
7585 if (T->isVoidType()) {
7586 // C++98 [dcl.stc]p5: The extern specifier can be applied only to the names
7587 // of objects and functions.
7588 if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) {
7589 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type)
7591 NewVD->setInvalidDecl();
7596 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) {
7597 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal);
7598 NewVD->setInvalidDecl();
7602 if (isVM && NewVD->hasAttr<BlocksAttr>()) {
7603 Diag(NewVD->getLocation(), diag::err_block_on_vm);
7604 NewVD->setInvalidDecl();
7608 if (NewVD->isConstexpr() && !T->isDependentType() &&
7609 RequireLiteralType(NewVD->getLocation(), T,
7610 diag::err_constexpr_var_non_literal)) {
7611 NewVD->setInvalidDecl();
7616 /// Perform semantic checking on a newly-created variable
7619 /// This routine performs all of the type-checking required for a
7620 /// variable declaration once it has been built. It is used both to
7621 /// check variables after they have been parsed and their declarators
7622 /// have been translated into a declaration, and to check variables
7623 /// that have been instantiated from a template.
7625 /// Sets NewVD->isInvalidDecl() if an error was encountered.
7627 /// Returns true if the variable declaration is a redeclaration.
7628 bool Sema::CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous) {
7629 CheckVariableDeclarationType(NewVD);
7631 // If the decl is already known invalid, don't check it.
7632 if (NewVD->isInvalidDecl())
7635 // If we did not find anything by this name, look for a non-visible
7636 // extern "C" declaration with the same name.
7637 if (Previous.empty() &&
7638 checkForConflictWithNonVisibleExternC(*this, NewVD, Previous))
7639 Previous.setShadowed();
7641 if (!Previous.empty()) {
7642 MergeVarDecl(NewVD, Previous);
7649 struct FindOverriddenMethod {
7651 CXXMethodDecl *Method;
7653 /// Member lookup function that determines whether a given C++
7654 /// method overrides a method in a base class, to be used with
7655 /// CXXRecordDecl::lookupInBases().
7656 bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
7657 RecordDecl *BaseRecord =
7658 Specifier->getType()->getAs<RecordType>()->getDecl();
7660 DeclarationName Name = Method->getDeclName();
7662 // FIXME: Do we care about other names here too?
7663 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7664 // We really want to find the base class destructor here.
7665 QualType T = S->Context.getTypeDeclType(BaseRecord);
7666 CanQualType CT = S->Context.getCanonicalType(T);
7668 Name = S->Context.DeclarationNames.getCXXDestructorName(CT);
7671 for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
7672 Path.Decls = Path.Decls.slice(1)) {
7673 NamedDecl *D = Path.Decls.front();
7674 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
7675 if (MD->isVirtual() && !S->IsOverload(Method, MD, false))
7684 enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted };
7685 } // end anonymous namespace
7687 /// Report an error regarding overriding, along with any relevant
7688 /// overridden methods.
7690 /// \param DiagID the primary error to report.
7691 /// \param MD the overriding method.
7692 /// \param OEK which overrides to include as notes.
7693 static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD,
7694 OverrideErrorKind OEK = OEK_All) {
7695 S.Diag(MD->getLocation(), DiagID) << MD->getDeclName();
7696 for (const CXXMethodDecl *O : MD->overridden_methods()) {
7697 // This check (& the OEK parameter) could be replaced by a predicate, but
7698 // without lambdas that would be overkill. This is still nicer than writing
7699 // out the diag loop 3 times.
7700 if ((OEK == OEK_All) ||
7701 (OEK == OEK_NonDeleted && !O->isDeleted()) ||
7702 (OEK == OEK_Deleted && O->isDeleted()))
7703 S.Diag(O->getLocation(), diag::note_overridden_virtual_function);
7707 /// AddOverriddenMethods - See if a method overrides any in the base classes,
7708 /// and if so, check that it's a valid override and remember it.
7709 bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) {
7710 // Look for methods in base classes that this method might override.
7712 FindOverriddenMethod FOM;
7715 bool hasDeletedOverridenMethods = false;
7716 bool hasNonDeletedOverridenMethods = false;
7717 bool AddedAny = false;
7718 if (DC->lookupInBases(FOM, Paths)) {
7719 for (auto *I : Paths.found_decls()) {
7720 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(I)) {
7721 MD->addOverriddenMethod(OldMD->getCanonicalDecl());
7722 if (!CheckOverridingFunctionReturnType(MD, OldMD) &&
7723 !CheckOverridingFunctionAttributes(MD, OldMD) &&
7724 !CheckOverridingFunctionExceptionSpec(MD, OldMD) &&
7725 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) {
7726 hasDeletedOverridenMethods |= OldMD->isDeleted();
7727 hasNonDeletedOverridenMethods |= !OldMD->isDeleted();
7734 if (hasDeletedOverridenMethods && !MD->isDeleted()) {
7735 ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted);
7737 if (hasNonDeletedOverridenMethods && MD->isDeleted()) {
7738 ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted);
7745 // Struct for holding all of the extra arguments needed by
7746 // DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator.
7747 struct ActOnFDArgs {
7750 MultiTemplateParamsArg TemplateParamLists;
7753 } // end anonymous namespace
7757 // Callback to only accept typo corrections that have a non-zero edit distance.
7758 // Also only accept corrections that have the same parent decl.
7759 class DifferentNameValidatorCCC final : public CorrectionCandidateCallback {
7761 DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD,
7762 CXXRecordDecl *Parent)
7763 : Context(Context), OriginalFD(TypoFD),
7764 ExpectedParent(Parent ? Parent->getCanonicalDecl() : nullptr) {}
7766 bool ValidateCandidate(const TypoCorrection &candidate) override {
7767 if (candidate.getEditDistance() == 0)
7770 SmallVector<unsigned, 1> MismatchedParams;
7771 for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(),
7772 CDeclEnd = candidate.end();
7773 CDecl != CDeclEnd; ++CDecl) {
7774 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7776 if (FD && !FD->hasBody() &&
7777 hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) {
7778 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
7779 CXXRecordDecl *Parent = MD->getParent();
7780 if (Parent && Parent->getCanonicalDecl() == ExpectedParent)
7782 } else if (!ExpectedParent) {
7791 std::unique_ptr<CorrectionCandidateCallback> clone() override {
7792 return llvm::make_unique<DifferentNameValidatorCCC>(*this);
7796 ASTContext &Context;
7797 FunctionDecl *OriginalFD;
7798 CXXRecordDecl *ExpectedParent;
7801 } // end anonymous namespace
7803 void Sema::MarkTypoCorrectedFunctionDefinition(const NamedDecl *F) {
7804 TypoCorrectedFunctionDefinitions.insert(F);
7807 /// Generate diagnostics for an invalid function redeclaration.
7809 /// This routine handles generating the diagnostic messages for an invalid
7810 /// function redeclaration, including finding possible similar declarations
7811 /// or performing typo correction if there are no previous declarations with
7814 /// Returns a NamedDecl iff typo correction was performed and substituting in
7815 /// the new declaration name does not cause new errors.
7816 static NamedDecl *DiagnoseInvalidRedeclaration(
7817 Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD,
7818 ActOnFDArgs &ExtraArgs, bool IsLocalFriend, Scope *S) {
7819 DeclarationName Name = NewFD->getDeclName();
7820 DeclContext *NewDC = NewFD->getDeclContext();
7821 SmallVector<unsigned, 1> MismatchedParams;
7822 SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches;
7823 TypoCorrection Correction;
7824 bool IsDefinition = ExtraArgs.D.isFunctionDefinition();
7826 IsLocalFriend ? diag::err_no_matching_local_friend :
7827 NewFD->getFriendObjectKind() ? diag::err_qualified_friend_no_match :
7828 diag::err_member_decl_does_not_match;
7829 LookupResult Prev(SemaRef, Name, NewFD->getLocation(),
7830 IsLocalFriend ? Sema::LookupLocalFriendName
7831 : Sema::LookupOrdinaryName,
7832 Sema::ForVisibleRedeclaration);
7834 NewFD->setInvalidDecl();
7836 SemaRef.LookupName(Prev, S);
7838 SemaRef.LookupQualifiedName(Prev, NewDC);
7839 assert(!Prev.isAmbiguous() &&
7840 "Cannot have an ambiguity in previous-declaration lookup");
7841 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
7842 DifferentNameValidatorCCC CCC(SemaRef.Context, NewFD,
7843 MD ? MD->getParent() : nullptr);
7844 if (!Prev.empty()) {
7845 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end();
7846 Func != FuncEnd; ++Func) {
7847 FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func);
7849 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7850 // Add 1 to the index so that 0 can mean the mismatch didn't
7851 // involve a parameter
7853 MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1;
7854 NearMatches.push_back(std::make_pair(FD, ParamNum));
7857 // If the qualified name lookup yielded nothing, try typo correction
7858 } else if ((Correction = SemaRef.CorrectTypo(
7859 Prev.getLookupNameInfo(), Prev.getLookupKind(), S,
7860 &ExtraArgs.D.getCXXScopeSpec(), CCC, Sema::CTK_ErrorRecovery,
7861 IsLocalFriend ? nullptr : NewDC))) {
7862 // Set up everything for the call to ActOnFunctionDeclarator
7863 ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(),
7864 ExtraArgs.D.getIdentifierLoc());
7866 Previous.setLookupName(Correction.getCorrection());
7867 for (TypoCorrection::decl_iterator CDecl = Correction.begin(),
7868 CDeclEnd = Correction.end();
7869 CDecl != CDeclEnd; ++CDecl) {
7870 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7871 if (FD && !FD->hasBody() &&
7872 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7873 Previous.addDecl(FD);
7876 bool wasRedeclaration = ExtraArgs.D.isRedeclaration();
7879 // Retry building the function declaration with the new previous
7880 // declarations, and with errors suppressed.
7883 Sema::SFINAETrap Trap(SemaRef);
7885 // TODO: Refactor ActOnFunctionDeclarator so that we can call only the
7886 // pieces need to verify the typo-corrected C++ declaration and hopefully
7887 // eliminate the need for the parameter pack ExtraArgs.
7888 Result = SemaRef.ActOnFunctionDeclarator(
7889 ExtraArgs.S, ExtraArgs.D,
7890 Correction.getCorrectionDecl()->getDeclContext(),
7891 NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists,
7892 ExtraArgs.AddToScope);
7894 if (Trap.hasErrorOccurred())
7899 // Determine which correction we picked.
7900 Decl *Canonical = Result->getCanonicalDecl();
7901 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
7903 if ((*I)->getCanonicalDecl() == Canonical)
7904 Correction.setCorrectionDecl(*I);
7906 // Let Sema know about the correction.
7907 SemaRef.MarkTypoCorrectedFunctionDefinition(Result);
7908 SemaRef.diagnoseTypo(
7910 SemaRef.PDiag(IsLocalFriend
7911 ? diag::err_no_matching_local_friend_suggest
7912 : diag::err_member_decl_does_not_match_suggest)
7913 << Name << NewDC << IsDefinition);
7917 // Pretend the typo correction never occurred
7918 ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(),
7919 ExtraArgs.D.getIdentifierLoc());
7920 ExtraArgs.D.setRedeclaration(wasRedeclaration);
7922 Previous.setLookupName(Name);
7925 SemaRef.Diag(NewFD->getLocation(), DiagMsg)
7926 << Name << NewDC << IsDefinition << NewFD->getLocation();
7928 bool NewFDisConst = false;
7929 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD))
7930 NewFDisConst = NewMD->isConst();
7932 for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator
7933 NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end();
7934 NearMatch != NearMatchEnd; ++NearMatch) {
7935 FunctionDecl *FD = NearMatch->first;
7936 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
7937 bool FDisConst = MD && MD->isConst();
7938 bool IsMember = MD || !IsLocalFriend;
7940 // FIXME: These notes are poorly worded for the local friend case.
7941 if (unsigned Idx = NearMatch->second) {
7942 ParmVarDecl *FDParam = FD->getParamDecl(Idx-1);
7943 SourceLocation Loc = FDParam->getTypeSpecStartLoc();
7944 if (Loc.isInvalid()) Loc = FD->getLocation();
7945 SemaRef.Diag(Loc, IsMember ? diag::note_member_def_close_param_match
7946 : diag::note_local_decl_close_param_match)
7947 << Idx << FDParam->getType()
7948 << NewFD->getParamDecl(Idx - 1)->getType();
7949 } else if (FDisConst != NewFDisConst) {
7950 SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match)
7951 << NewFDisConst << FD->getSourceRange().getEnd();
7953 SemaRef.Diag(FD->getLocation(),
7954 IsMember ? diag::note_member_def_close_match
7955 : diag::note_local_decl_close_match);
7960 static StorageClass getFunctionStorageClass(Sema &SemaRef, Declarator &D) {
7961 switch (D.getDeclSpec().getStorageClassSpec()) {
7962 default: llvm_unreachable("Unknown storage class!");
7963 case DeclSpec::SCS_auto:
7964 case DeclSpec::SCS_register:
7965 case DeclSpec::SCS_mutable:
7966 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7967 diag::err_typecheck_sclass_func);
7968 D.getMutableDeclSpec().ClearStorageClassSpecs();
7971 case DeclSpec::SCS_unspecified: break;
7972 case DeclSpec::SCS_extern:
7973 if (D.getDeclSpec().isExternInLinkageSpec())
7976 case DeclSpec::SCS_static: {
7977 if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) {
7979 // The declaration of an identifier for a function that has
7980 // block scope shall have no explicit storage-class specifier
7981 // other than extern
7982 // See also (C++ [dcl.stc]p4).
7983 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7984 diag::err_static_block_func);
7989 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
7992 // No explicit storage class has already been returned
7996 static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
7997 DeclContext *DC, QualType &R,
7998 TypeSourceInfo *TInfo,
8000 bool &IsVirtualOkay) {
8001 DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D);
8002 DeclarationName Name = NameInfo.getName();
8004 FunctionDecl *NewFD = nullptr;
8005 bool isInline = D.getDeclSpec().isInlineSpecified();
8007 if (!SemaRef.getLangOpts().CPlusPlus) {
8008 // Determine whether the function was written with a
8009 // prototype. This true when:
8010 // - there is a prototype in the declarator, or
8011 // - the type R of the function is some kind of typedef or other non-
8012 // attributed reference to a type name (which eventually refers to a
8015 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) ||
8016 (!R->getAsAdjusted<FunctionType>() && R->isFunctionProtoType());
8018 NewFD = FunctionDecl::Create(SemaRef.Context, DC, D.getBeginLoc(), NameInfo,
8019 R, TInfo, SC, isInline, HasPrototype,
8021 if (D.isInvalidType())
8022 NewFD->setInvalidDecl();
8027 ExplicitSpecifier ExplicitSpecifier = D.getDeclSpec().getExplicitSpecifier();
8028 ConstexprSpecKind ConstexprKind = D.getDeclSpec().getConstexprSpecifier();
8029 // Check that the return type is not an abstract class type.
8030 // For record types, this is done by the AbstractClassUsageDiagnoser once
8031 // the class has been completely parsed.
8032 if (!DC->isRecord() &&
8033 SemaRef.RequireNonAbstractType(
8034 D.getIdentifierLoc(), R->getAs<FunctionType>()->getReturnType(),
8035 diag::err_abstract_type_in_decl, SemaRef.AbstractReturnType))
8038 if (Name.getNameKind() == DeclarationName::CXXConstructorName) {
8039 // This is a C++ constructor declaration.
8040 assert(DC->isRecord() &&
8041 "Constructors can only be declared in a member context");
8043 R = SemaRef.CheckConstructorDeclarator(D, R, SC);
8044 return CXXConstructorDecl::Create(
8045 SemaRef.Context, cast<CXXRecordDecl>(DC), D.getBeginLoc(), NameInfo, R,
8046 TInfo, ExplicitSpecifier, isInline,
8047 /*isImplicitlyDeclared=*/false, ConstexprKind);
8049 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
8050 // This is a C++ destructor declaration.
8051 if (DC->isRecord()) {
8052 R = SemaRef.CheckDestructorDeclarator(D, R, SC);
8053 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
8054 CXXDestructorDecl *NewDD =
8055 CXXDestructorDecl::Create(SemaRef.Context, Record, D.getBeginLoc(),
8056 NameInfo, R, TInfo, isInline,
8057 /*isImplicitlyDeclared=*/false);
8059 // If the destructor needs an implicit exception specification, set it
8060 // now. FIXME: It'd be nice to be able to create the right type to start
8061 // with, but the type needs to reference the destructor declaration.
8062 if (SemaRef.getLangOpts().CPlusPlus11)
8063 SemaRef.AdjustDestructorExceptionSpec(NewDD);
8065 IsVirtualOkay = true;
8069 SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member);
8072 // Create a FunctionDecl to satisfy the function definition parsing
8074 return FunctionDecl::Create(SemaRef.Context, DC, D.getBeginLoc(),
8075 D.getIdentifierLoc(), Name, R, TInfo, SC,
8077 /*hasPrototype=*/true, ConstexprKind);
8080 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
8081 if (!DC->isRecord()) {
8082 SemaRef.Diag(D.getIdentifierLoc(),
8083 diag::err_conv_function_not_member);
8087 SemaRef.CheckConversionDeclarator(D, R, SC);
8088 IsVirtualOkay = true;
8089 return CXXConversionDecl::Create(
8090 SemaRef.Context, cast<CXXRecordDecl>(DC), D.getBeginLoc(), NameInfo, R,
8091 TInfo, isInline, ExplicitSpecifier, ConstexprKind, SourceLocation());
8093 } else if (Name.getNameKind() == DeclarationName::CXXDeductionGuideName) {
8094 SemaRef.CheckDeductionGuideDeclarator(D, R, SC);
8096 return CXXDeductionGuideDecl::Create(SemaRef.Context, DC, D.getBeginLoc(),
8097 ExplicitSpecifier, NameInfo, R, TInfo,
8099 } else if (DC->isRecord()) {
8100 // If the name of the function is the same as the name of the record,
8101 // then this must be an invalid constructor that has a return type.
8102 // (The parser checks for a return type and makes the declarator a
8103 // constructor if it has no return type).
8104 if (Name.getAsIdentifierInfo() &&
8105 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){
8106 SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type)
8107 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
8108 << SourceRange(D.getIdentifierLoc());
8112 // This is a C++ method declaration.
8113 CXXMethodDecl *Ret = CXXMethodDecl::Create(
8114 SemaRef.Context, cast<CXXRecordDecl>(DC), D.getBeginLoc(), NameInfo, R,
8115 TInfo, SC, isInline, ConstexprKind, SourceLocation());
8116 IsVirtualOkay = !Ret->isStatic();
8120 SemaRef.getLangOpts().CPlusPlus && D.getDeclSpec().isFriendSpecified();
8121 if (!isFriend && SemaRef.CurContext->isRecord())
8124 // Determine whether the function was written with a
8125 // prototype. This true when:
8126 // - we're in C++ (where every function has a prototype),
8127 return FunctionDecl::Create(SemaRef.Context, DC, D.getBeginLoc(), NameInfo,
8128 R, TInfo, SC, isInline, true /*HasPrototype*/,
8133 enum OpenCLParamType {
8137 InvalidAddrSpacePtrKernelParam,
8142 static bool isOpenCLSizeDependentType(ASTContext &C, QualType Ty) {
8143 // Size dependent types are just typedefs to normal integer types
8144 // (e.g. unsigned long), so we cannot distinguish them from other typedefs to
8145 // integers other than by their names.
8146 StringRef SizeTypeNames[] = {"size_t", "intptr_t", "uintptr_t", "ptrdiff_t"};
8148 // Remove typedefs one by one until we reach a typedef
8149 // for a size dependent type.
8150 QualType DesugaredTy = Ty;
8152 ArrayRef<StringRef> Names(SizeTypeNames);
8153 auto Match = llvm::find(Names, DesugaredTy.getAsString());
8154 if (Names.end() != Match)
8158 DesugaredTy = Ty.getSingleStepDesugaredType(C);
8159 } while (DesugaredTy != Ty);
8164 static OpenCLParamType getOpenCLKernelParameterType(Sema &S, QualType PT) {
8165 if (PT->isPointerType()) {
8166 QualType PointeeType = PT->getPointeeType();
8167 if (PointeeType->isPointerType())
8168 return PtrPtrKernelParam;
8169 if (PointeeType.getAddressSpace() == LangAS::opencl_generic ||
8170 PointeeType.getAddressSpace() == LangAS::opencl_private ||
8171 PointeeType.getAddressSpace() == LangAS::Default)
8172 return InvalidAddrSpacePtrKernelParam;
8173 return PtrKernelParam;
8176 // OpenCL v1.2 s6.9.k:
8177 // Arguments to kernel functions in a program cannot be declared with the
8178 // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and
8179 // uintptr_t or a struct and/or union that contain fields declared to be one
8180 // of these built-in scalar types.
8181 if (isOpenCLSizeDependentType(S.getASTContext(), PT))
8182 return InvalidKernelParam;
8184 if (PT->isImageType())
8185 return PtrKernelParam;
8187 if (PT->isBooleanType() || PT->isEventT() || PT->isReserveIDT())
8188 return InvalidKernelParam;
8190 // OpenCL extension spec v1.2 s9.5:
8191 // This extension adds support for half scalar and vector types as built-in
8192 // types that can be used for arithmetic operations, conversions etc.
8193 if (!S.getOpenCLOptions().isEnabled("cl_khr_fp16") && PT->isHalfType())
8194 return InvalidKernelParam;
8196 if (PT->isRecordType())
8197 return RecordKernelParam;
8199 // Look into an array argument to check if it has a forbidden type.
8200 if (PT->isArrayType()) {
8201 const Type *UnderlyingTy = PT->getPointeeOrArrayElementType();
8202 // Call ourself to check an underlying type of an array. Since the
8203 // getPointeeOrArrayElementType returns an innermost type which is not an
8204 // array, this recursive call only happens once.
8205 return getOpenCLKernelParameterType(S, QualType(UnderlyingTy, 0));
8208 return ValidKernelParam;
8211 static void checkIsValidOpenCLKernelParameter(
8215 llvm::SmallPtrSetImpl<const Type *> &ValidTypes) {
8216 QualType PT = Param->getType();
8218 // Cache the valid types we encounter to avoid rechecking structs that are
8220 if (ValidTypes.count(PT.getTypePtr()))
8223 switch (getOpenCLKernelParameterType(S, PT)) {
8224 case PtrPtrKernelParam:
8225 // OpenCL v1.2 s6.9.a:
8226 // A kernel function argument cannot be declared as a
8227 // pointer to a pointer type.
8228 S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param);
8232 case InvalidAddrSpacePtrKernelParam:
8233 // OpenCL v1.0 s6.5:
8234 // __kernel function arguments declared to be a pointer of a type can point
8235 // to one of the following address spaces only : __global, __local or
8237 S.Diag(Param->getLocation(), diag::err_kernel_arg_address_space);
8241 // OpenCL v1.2 s6.9.k:
8242 // Arguments to kernel functions in a program cannot be declared with the
8243 // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and
8244 // uintptr_t or a struct and/or union that contain fields declared to be
8245 // one of these built-in scalar types.
8247 case InvalidKernelParam:
8248 // OpenCL v1.2 s6.8 n:
8249 // A kernel function argument cannot be declared
8251 // Do not diagnose half type since it is diagnosed as invalid argument
8252 // type for any function elsewhere.
8253 if (!PT->isHalfType()) {
8254 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
8256 // Explain what typedefs are involved.
8257 const TypedefType *Typedef = nullptr;
8258 while ((Typedef = PT->getAs<TypedefType>())) {
8259 SourceLocation Loc = Typedef->getDecl()->getLocation();
8260 // SourceLocation may be invalid for a built-in type.
8262 S.Diag(Loc, diag::note_entity_declared_at) << PT;
8263 PT = Typedef->desugar();
8270 case PtrKernelParam:
8271 case ValidKernelParam:
8272 ValidTypes.insert(PT.getTypePtr());
8275 case RecordKernelParam:
8279 // Track nested structs we will inspect
8280 SmallVector<const Decl *, 4> VisitStack;
8282 // Track where we are in the nested structs. Items will migrate from
8283 // VisitStack to HistoryStack as we do the DFS for bad field.
8284 SmallVector<const FieldDecl *, 4> HistoryStack;
8285 HistoryStack.push_back(nullptr);
8287 // At this point we already handled everything except of a RecordType or
8288 // an ArrayType of a RecordType.
8289 assert((PT->isArrayType() || PT->isRecordType()) && "Unexpected type.");
8290 const RecordType *RecTy =
8291 PT->getPointeeOrArrayElementType()->getAs<RecordType>();
8292 const RecordDecl *OrigRecDecl = RecTy->getDecl();
8294 VisitStack.push_back(RecTy->getDecl());
8295 assert(VisitStack.back() && "First decl null?");
8298 const Decl *Next = VisitStack.pop_back_val();
8300 assert(!HistoryStack.empty());
8301 // Found a marker, we have gone up a level
8302 if (const FieldDecl *Hist = HistoryStack.pop_back_val())
8303 ValidTypes.insert(Hist->getType().getTypePtr());
8308 // Adds everything except the original parameter declaration (which is not a
8309 // field itself) to the history stack.
8310 const RecordDecl *RD;
8311 if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) {
8312 HistoryStack.push_back(Field);
8314 QualType FieldTy = Field->getType();
8315 // Other field types (known to be valid or invalid) are handled while we
8316 // walk around RecordDecl::fields().
8317 assert((FieldTy->isArrayType() || FieldTy->isRecordType()) &&
8318 "Unexpected type.");
8319 const Type *FieldRecTy = FieldTy->getPointeeOrArrayElementType();
8321 RD = FieldRecTy->castAs<RecordType>()->getDecl();
8323 RD = cast<RecordDecl>(Next);
8326 // Add a null marker so we know when we've gone back up a level
8327 VisitStack.push_back(nullptr);
8329 for (const auto *FD : RD->fields()) {
8330 QualType QT = FD->getType();
8332 if (ValidTypes.count(QT.getTypePtr()))
8335 OpenCLParamType ParamType = getOpenCLKernelParameterType(S, QT);
8336 if (ParamType == ValidKernelParam)
8339 if (ParamType == RecordKernelParam) {
8340 VisitStack.push_back(FD);
8344 // OpenCL v1.2 s6.9.p:
8345 // Arguments to kernel functions that are declared to be a struct or union
8346 // do not allow OpenCL objects to be passed as elements of the struct or
8348 if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam ||
8349 ParamType == InvalidAddrSpacePtrKernelParam) {
8350 S.Diag(Param->getLocation(),
8351 diag::err_record_with_pointers_kernel_param)
8352 << PT->isUnionType()
8355 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
8358 S.Diag(OrigRecDecl->getLocation(), diag::note_within_field_of_type)
8359 << OrigRecDecl->getDeclName();
8361 // We have an error, now let's go back up through history and show where
8362 // the offending field came from
8363 for (ArrayRef<const FieldDecl *>::const_iterator
8364 I = HistoryStack.begin() + 1,
8365 E = HistoryStack.end();
8367 const FieldDecl *OuterField = *I;
8368 S.Diag(OuterField->getLocation(), diag::note_within_field_of_type)
8369 << OuterField->getType();
8372 S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here)
8373 << QT->isPointerType()
8378 } while (!VisitStack.empty());
8381 /// Find the DeclContext in which a tag is implicitly declared if we see an
8382 /// elaborated type specifier in the specified context, and lookup finds
8384 static DeclContext *getTagInjectionContext(DeclContext *DC) {
8385 while (!DC->isFileContext() && !DC->isFunctionOrMethod())
8386 DC = DC->getParent();
8390 /// Find the Scope in which a tag is implicitly declared if we see an
8391 /// elaborated type specifier in the specified context, and lookup finds
8393 static Scope *getTagInjectionScope(Scope *S, const LangOptions &LangOpts) {
8394 while (S->isClassScope() ||
8395 (LangOpts.CPlusPlus &&
8396 S->isFunctionPrototypeScope()) ||
8397 ((S->getFlags() & Scope::DeclScope) == 0) ||
8398 (S->getEntity() && S->getEntity()->isTransparentContext()))
8404 Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
8405 TypeSourceInfo *TInfo, LookupResult &Previous,
8406 MultiTemplateParamsArg TemplateParamLists,
8408 QualType R = TInfo->getType();
8410 assert(R->isFunctionType());
8412 // TODO: consider using NameInfo for diagnostic.
8413 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
8414 DeclarationName Name = NameInfo.getName();
8415 StorageClass SC = getFunctionStorageClass(*this, D);
8417 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
8418 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
8419 diag::err_invalid_thread)
8420 << DeclSpec::getSpecifierName(TSCS);
8422 if (D.isFirstDeclarationOfMember())
8423 adjustMemberFunctionCC(R, D.isStaticMember(), D.isCtorOrDtor(),
8424 D.getIdentifierLoc());
8426 bool isFriend = false;
8427 FunctionTemplateDecl *FunctionTemplate = nullptr;
8428 bool isMemberSpecialization = false;
8429 bool isFunctionTemplateSpecialization = false;
8431 bool isDependentClassScopeExplicitSpecialization = false;
8432 bool HasExplicitTemplateArgs = false;
8433 TemplateArgumentListInfo TemplateArgs;
8435 bool isVirtualOkay = false;
8437 DeclContext *OriginalDC = DC;
8438 bool IsLocalExternDecl = adjustContextForLocalExternDecl(DC);
8440 FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC,
8442 if (!NewFD) return nullptr;
8444 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer())
8445 NewFD->setTopLevelDeclInObjCContainer();
8447 // Set the lexical context. If this is a function-scope declaration, or has a
8448 // C++ scope specifier, or is the object of a friend declaration, the lexical
8449 // context will be different from the semantic context.
8450 NewFD->setLexicalDeclContext(CurContext);
8452 if (IsLocalExternDecl)
8453 NewFD->setLocalExternDecl();
8455 if (getLangOpts().CPlusPlus) {
8456 bool isInline = D.getDeclSpec().isInlineSpecified();
8457 bool isVirtual = D.getDeclSpec().isVirtualSpecified();
8458 bool hasExplicit = D.getDeclSpec().hasExplicitSpecifier();
8459 ConstexprSpecKind ConstexprKind = D.getDeclSpec().getConstexprSpecifier();
8460 isFriend = D.getDeclSpec().isFriendSpecified();
8461 if (isFriend && !isInline && D.isFunctionDefinition()) {
8462 // C++ [class.friend]p5
8463 // A function can be defined in a friend declaration of a
8464 // class . . . . Such a function is implicitly inline.
8465 NewFD->setImplicitlyInline();
8468 // If this is a method defined in an __interface, and is not a constructor
8469 // or an overloaded operator, then set the pure flag (isVirtual will already
8471 if (const CXXRecordDecl *Parent =
8472 dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) {
8473 if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided())
8474 NewFD->setPure(true);
8476 // C++ [class.union]p2
8477 // A union can have member functions, but not virtual functions.
8478 if (isVirtual && Parent->isUnion())
8479 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_in_union);
8482 SetNestedNameSpecifier(*this, NewFD, D);
8483 isMemberSpecialization = false;
8484 isFunctionTemplateSpecialization = false;
8485 if (D.isInvalidType())
8486 NewFD->setInvalidDecl();
8488 // Match up the template parameter lists with the scope specifier, then
8489 // determine whether we have a template or a template specialization.
8490 bool Invalid = false;
8491 if (TemplateParameterList *TemplateParams =
8492 MatchTemplateParametersToScopeSpecifier(
8493 D.getDeclSpec().getBeginLoc(), D.getIdentifierLoc(),
8494 D.getCXXScopeSpec(),
8495 D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId
8496 ? D.getName().TemplateId
8498 TemplateParamLists, isFriend, isMemberSpecialization,
8500 if (TemplateParams->size() > 0) {
8501 // This is a function template
8503 // Check that we can declare a template here.
8504 if (CheckTemplateDeclScope(S, TemplateParams))
8505 NewFD->setInvalidDecl();
8507 // A destructor cannot be a template.
8508 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
8509 Diag(NewFD->getLocation(), diag::err_destructor_template);
8510 NewFD->setInvalidDecl();
8513 // If we're adding a template to a dependent context, we may need to
8514 // rebuilding some of the types used within the template parameter list,
8515 // now that we know what the current instantiation is.
8516 if (DC->isDependentContext()) {
8517 ContextRAII SavedContext(*this, DC);
8518 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
8522 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC,
8523 NewFD->getLocation(),
8524 Name, TemplateParams,
8526 FunctionTemplate->setLexicalDeclContext(CurContext);
8527 NewFD->setDescribedFunctionTemplate(FunctionTemplate);
8529 // For source fidelity, store the other template param lists.
8530 if (TemplateParamLists.size() > 1) {
8531 NewFD->setTemplateParameterListsInfo(Context,
8532 TemplateParamLists.drop_back(1));
8535 // This is a function template specialization.
8536 isFunctionTemplateSpecialization = true;
8537 // For source fidelity, store all the template param lists.
8538 if (TemplateParamLists.size() > 0)
8539 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
8541 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);".
8543 // We want to remove the "template<>", found here.
8544 SourceRange RemoveRange = TemplateParams->getSourceRange();
8546 // If we remove the template<> and the name is not a
8547 // template-id, we're actually silently creating a problem:
8548 // the friend declaration will refer to an untemplated decl,
8549 // and clearly the user wants a template specialization. So
8550 // we need to insert '<>' after the name.
8551 SourceLocation InsertLoc;
8552 if (D.getName().getKind() != UnqualifiedIdKind::IK_TemplateId) {
8553 InsertLoc = D.getName().getSourceRange().getEnd();
8554 InsertLoc = getLocForEndOfToken(InsertLoc);
8557 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend)
8558 << Name << RemoveRange
8559 << FixItHint::CreateRemoval(RemoveRange)
8560 << FixItHint::CreateInsertion(InsertLoc, "<>");
8564 // All template param lists were matched against the scope specifier:
8565 // this is NOT (an explicit specialization of) a template.
8566 if (TemplateParamLists.size() > 0)
8567 // For source fidelity, store all the template param lists.
8568 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
8572 NewFD->setInvalidDecl();
8573 if (FunctionTemplate)
8574 FunctionTemplate->setInvalidDecl();
8577 // C++ [dcl.fct.spec]p5:
8578 // The virtual specifier shall only be used in declarations of
8579 // nonstatic class member functions that appear within a
8580 // member-specification of a class declaration; see 10.3.
8582 if (isVirtual && !NewFD->isInvalidDecl()) {
8583 if (!isVirtualOkay) {
8584 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8585 diag::err_virtual_non_function);
8586 } else if (!CurContext->isRecord()) {
8587 // 'virtual' was specified outside of the class.
8588 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8589 diag::err_virtual_out_of_class)
8590 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
8591 } else if (NewFD->getDescribedFunctionTemplate()) {
8592 // C++ [temp.mem]p3:
8593 // A member function template shall not be virtual.
8594 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8595 diag::err_virtual_member_function_template)
8596 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
8598 // Okay: Add virtual to the method.
8599 NewFD->setVirtualAsWritten(true);
8602 if (getLangOpts().CPlusPlus14 &&
8603 NewFD->getReturnType()->isUndeducedType())
8604 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual);
8607 if (getLangOpts().CPlusPlus14 &&
8608 (NewFD->isDependentContext() ||
8609 (isFriend && CurContext->isDependentContext())) &&
8610 NewFD->getReturnType()->isUndeducedType()) {
8611 // If the function template is referenced directly (for instance, as a
8612 // member of the current instantiation), pretend it has a dependent type.
8613 // This is not really justified by the standard, but is the only sane
8615 // FIXME: For a friend function, we have not marked the function as being
8616 // a friend yet, so 'isDependentContext' on the FD doesn't work.
8617 const FunctionProtoType *FPT =
8618 NewFD->getType()->castAs<FunctionProtoType>();
8620 SubstAutoType(FPT->getReturnType(), Context.DependentTy);
8621 NewFD->setType(Context.getFunctionType(Result, FPT->getParamTypes(),
8622 FPT->getExtProtoInfo()));
8625 // C++ [dcl.fct.spec]p3:
8626 // The inline specifier shall not appear on a block scope function
8628 if (isInline && !NewFD->isInvalidDecl()) {
8629 if (CurContext->isFunctionOrMethod()) {
8630 // 'inline' is not allowed on block scope function declaration.
8631 Diag(D.getDeclSpec().getInlineSpecLoc(),
8632 diag::err_inline_declaration_block_scope) << Name
8633 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
8637 // C++ [dcl.fct.spec]p6:
8638 // The explicit specifier shall be used only in the declaration of a
8639 // constructor or conversion function within its class definition;
8640 // see 12.3.1 and 12.3.2.
8641 if (hasExplicit && !NewFD->isInvalidDecl() &&
8642 !isa<CXXDeductionGuideDecl>(NewFD)) {
8643 if (!CurContext->isRecord()) {
8644 // 'explicit' was specified outside of the class.
8645 Diag(D.getDeclSpec().getExplicitSpecLoc(),
8646 diag::err_explicit_out_of_class)
8647 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecRange());
8648 } else if (!isa<CXXConstructorDecl>(NewFD) &&
8649 !isa<CXXConversionDecl>(NewFD)) {
8650 // 'explicit' was specified on a function that wasn't a constructor
8651 // or conversion function.
8652 Diag(D.getDeclSpec().getExplicitSpecLoc(),
8653 diag::err_explicit_non_ctor_or_conv_function)
8654 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecRange());
8658 if (ConstexprKind != CSK_unspecified) {
8659 // C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors
8660 // are implicitly inline.
8661 NewFD->setImplicitlyInline();
8663 // C++11 [dcl.constexpr]p3: functions declared constexpr are required to
8664 // be either constructors or to return a literal type. Therefore,
8665 // destructors cannot be declared constexpr.
8666 if (isa<CXXDestructorDecl>(NewFD))
8667 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor)
8668 << (ConstexprKind == CSK_consteval);
8671 // If __module_private__ was specified, mark the function accordingly.
8672 if (D.getDeclSpec().isModulePrivateSpecified()) {
8673 if (isFunctionTemplateSpecialization) {
8674 SourceLocation ModulePrivateLoc
8675 = D.getDeclSpec().getModulePrivateSpecLoc();
8676 Diag(ModulePrivateLoc, diag::err_module_private_specialization)
8678 << FixItHint::CreateRemoval(ModulePrivateLoc);
8680 NewFD->setModulePrivate();
8681 if (FunctionTemplate)
8682 FunctionTemplate->setModulePrivate();
8687 if (FunctionTemplate) {
8688 FunctionTemplate->setObjectOfFriendDecl();
8689 FunctionTemplate->setAccess(AS_public);
8691 NewFD->setObjectOfFriendDecl();
8692 NewFD->setAccess(AS_public);
8695 // If a function is defined as defaulted or deleted, mark it as such now.
8696 // FIXME: Does this ever happen? ActOnStartOfFunctionDef forces the function
8697 // definition kind to FDK_Definition.
8698 switch (D.getFunctionDefinitionKind()) {
8699 case FDK_Declaration:
8700 case FDK_Definition:
8704 NewFD->setDefaulted();
8708 NewFD->setDeletedAsWritten();
8712 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext &&
8713 D.isFunctionDefinition()) {
8714 // C++ [class.mfct]p2:
8715 // A member function may be defined (8.4) in its class definition, in
8716 // which case it is an inline member function (7.1.2)
8717 NewFD->setImplicitlyInline();
8720 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) &&
8721 !CurContext->isRecord()) {
8722 // C++ [class.static]p1:
8723 // A data or function member of a class may be declared static
8724 // in a class definition, in which case it is a static member of
8727 // Complain about the 'static' specifier if it's on an out-of-line
8728 // member function definition.
8730 // MSVC permits the use of a 'static' storage specifier on an out-of-line
8731 // member function template declaration and class member template
8732 // declaration (MSVC versions before 2015), warn about this.
8733 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
8734 ((!getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
8735 cast<CXXRecordDecl>(DC)->getDescribedClassTemplate()) ||
8736 (getLangOpts().MSVCCompat && NewFD->getDescribedFunctionTemplate()))
8737 ? diag::ext_static_out_of_line : diag::err_static_out_of_line)
8738 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
8741 // C++11 [except.spec]p15:
8742 // A deallocation function with no exception-specification is treated
8743 // as if it were specified with noexcept(true).
8744 const FunctionProtoType *FPT = R->getAs<FunctionProtoType>();
8745 if ((Name.getCXXOverloadedOperator() == OO_Delete ||
8746 Name.getCXXOverloadedOperator() == OO_Array_Delete) &&
8747 getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec())
8748 NewFD->setType(Context.getFunctionType(
8749 FPT->getReturnType(), FPT->getParamTypes(),
8750 FPT->getExtProtoInfo().withExceptionSpec(EST_BasicNoexcept)));
8753 // Filter out previous declarations that don't match the scope.
8754 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewFD),
8755 D.getCXXScopeSpec().isNotEmpty() ||
8756 isMemberSpecialization ||
8757 isFunctionTemplateSpecialization);
8759 // Handle GNU asm-label extension (encoded as an attribute).
8760 if (Expr *E = (Expr*) D.getAsmLabel()) {
8761 // The parser guarantees this is a string.
8762 StringLiteral *SE = cast<StringLiteral>(E);
8763 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context,
8764 SE->getString(), 0));
8765 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
8766 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
8767 ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier());
8768 if (I != ExtnameUndeclaredIdentifiers.end()) {
8769 if (isDeclExternC(NewFD)) {
8770 NewFD->addAttr(I->second);
8771 ExtnameUndeclaredIdentifiers.erase(I);
8773 Diag(NewFD->getLocation(), diag::warn_redefine_extname_not_applied)
8774 << /*Variable*/0 << NewFD;
8778 // Copy the parameter declarations from the declarator D to the function
8779 // declaration NewFD, if they are available. First scavenge them into Params.
8780 SmallVector<ParmVarDecl*, 16> Params;
8782 if (D.isFunctionDeclarator(FTIIdx)) {
8783 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(FTIIdx).Fun;
8785 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs
8786 // function that takes no arguments, not a function that takes a
8787 // single void argument.
8788 // We let through "const void" here because Sema::GetTypeForDeclarator
8789 // already checks for that case.
8790 if (FTIHasNonVoidParameters(FTI) && FTI.Params[0].Param) {
8791 for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) {
8792 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
8793 assert(Param->getDeclContext() != NewFD && "Was set before ?");
8794 Param->setDeclContext(NewFD);
8795 Params.push_back(Param);
8797 if (Param->isInvalidDecl())
8798 NewFD->setInvalidDecl();
8802 if (!getLangOpts().CPlusPlus) {
8803 // In C, find all the tag declarations from the prototype and move them
8804 // into the function DeclContext. Remove them from the surrounding tag
8805 // injection context of the function, which is typically but not always
8807 DeclContext *PrototypeTagContext =
8808 getTagInjectionContext(NewFD->getLexicalDeclContext());
8809 for (NamedDecl *NonParmDecl : FTI.getDeclsInPrototype()) {
8810 auto *TD = dyn_cast<TagDecl>(NonParmDecl);
8812 // We don't want to reparent enumerators. Look at their parent enum
8815 if (auto *ECD = dyn_cast<EnumConstantDecl>(NonParmDecl))
8816 TD = cast<EnumDecl>(ECD->getDeclContext());
8820 DeclContext *TagDC = TD->getLexicalDeclContext();
8821 if (!TagDC->containsDecl(TD))
8823 TagDC->removeDecl(TD);
8824 TD->setDeclContext(NewFD);
8827 // Preserve the lexical DeclContext if it is not the surrounding tag
8828 // injection context of the FD. In this example, the semantic context of
8829 // E will be f and the lexical context will be S, while both the
8830 // semantic and lexical contexts of S will be f:
8831 // void f(struct S { enum E { a } f; } s);
8832 if (TagDC != PrototypeTagContext)
8833 TD->setLexicalDeclContext(TagDC);
8836 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) {
8837 // When we're declaring a function with a typedef, typeof, etc as in the
8838 // following example, we'll need to synthesize (unnamed)
8839 // parameters for use in the declaration.
8842 // typedef void fn(int);
8846 // Synthesize a parameter for each argument type.
8847 for (const auto &AI : FT->param_types()) {
8848 ParmVarDecl *Param =
8849 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), AI);
8850 Param->setScopeInfo(0, Params.size());
8851 Params.push_back(Param);
8854 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 &&
8855 "Should not need args for typedef of non-prototype fn");
8858 // Finally, we know we have the right number of parameters, install them.
8859 NewFD->setParams(Params);
8861 if (D.getDeclSpec().isNoreturnSpecified())
8863 ::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(),
8866 // Functions returning a variably modified type violate C99 6.7.5.2p2
8867 // because all functions have linkage.
8868 if (!NewFD->isInvalidDecl() &&
8869 NewFD->getReturnType()->isVariablyModifiedType()) {
8870 Diag(NewFD->getLocation(), diag::err_vm_func_decl);
8871 NewFD->setInvalidDecl();
8874 // Apply an implicit SectionAttr if '#pragma clang section text' is active
8875 if (PragmaClangTextSection.Valid && D.isFunctionDefinition() &&
8876 !NewFD->hasAttr<SectionAttr>()) {
8877 NewFD->addAttr(PragmaClangTextSectionAttr::CreateImplicit(Context,
8878 PragmaClangTextSection.SectionName,
8879 PragmaClangTextSection.PragmaLocation));
8882 // Apply an implicit SectionAttr if #pragma code_seg is active.
8883 if (CodeSegStack.CurrentValue && D.isFunctionDefinition() &&
8884 !NewFD->hasAttr<SectionAttr>()) {
8886 SectionAttr::CreateImplicit(Context, SectionAttr::Declspec_allocate,
8887 CodeSegStack.CurrentValue->getString(),
8888 CodeSegStack.CurrentPragmaLocation));
8889 if (UnifySection(CodeSegStack.CurrentValue->getString(),
8890 ASTContext::PSF_Implicit | ASTContext::PSF_Execute |
8891 ASTContext::PSF_Read,
8893 NewFD->dropAttr<SectionAttr>();
8896 // Apply an implicit CodeSegAttr from class declspec or
8897 // apply an implicit SectionAttr from #pragma code_seg if active.
8898 if (!NewFD->hasAttr<CodeSegAttr>()) {
8899 if (Attr *SAttr = getImplicitCodeSegOrSectionAttrForFunction(NewFD,
8900 D.isFunctionDefinition())) {
8901 NewFD->addAttr(SAttr);
8905 // Handle attributes.
8906 ProcessDeclAttributes(S, NewFD, D);
8908 if (getLangOpts().OpenCL) {
8909 // OpenCL v1.1 s6.5: Using an address space qualifier in a function return
8910 // type declaration will generate a compilation error.
8911 LangAS AddressSpace = NewFD->getReturnType().getAddressSpace();
8912 if (AddressSpace != LangAS::Default) {
8913 Diag(NewFD->getLocation(),
8914 diag::err_opencl_return_value_with_address_space);
8915 NewFD->setInvalidDecl();
8919 if (!getLangOpts().CPlusPlus) {
8920 // Perform semantic checking on the function declaration.
8921 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8922 CheckMain(NewFD, D.getDeclSpec());
8924 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8925 CheckMSVCRTEntryPoint(NewFD);
8927 if (!NewFD->isInvalidDecl())
8928 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8929 isMemberSpecialization));
8930 else if (!Previous.empty())
8931 // Recover gracefully from an invalid redeclaration.
8932 D.setRedeclaration(true);
8933 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8934 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8935 "previous declaration set still overloaded");
8937 // Diagnose no-prototype function declarations with calling conventions that
8938 // don't support variadic calls. Only do this in C and do it after merging
8939 // possibly prototyped redeclarations.
8940 const FunctionType *FT = NewFD->getType()->castAs<FunctionType>();
8941 if (isa<FunctionNoProtoType>(FT) && !D.isFunctionDefinition()) {
8942 CallingConv CC = FT->getExtInfo().getCC();
8943 if (!supportsVariadicCall(CC)) {
8944 // Windows system headers sometimes accidentally use stdcall without
8945 // (void) parameters, so we relax this to a warning.
8947 CC == CC_X86StdCall ? diag::warn_cconv_knr : diag::err_cconv_knr;
8948 Diag(NewFD->getLocation(), DiagID)
8949 << FunctionType::getNameForCallConv(CC);
8953 if (NewFD->getReturnType().hasNonTrivialToPrimitiveDestructCUnion() ||
8954 NewFD->getReturnType().hasNonTrivialToPrimitiveCopyCUnion())
8955 checkNonTrivialCUnion(NewFD->getReturnType(),
8956 NewFD->getReturnTypeSourceRange().getBegin(),
8957 NTCUC_FunctionReturn, NTCUK_Destruct|NTCUK_Copy);
8959 // C++11 [replacement.functions]p3:
8960 // The program's definitions shall not be specified as inline.
8962 // N.B. We diagnose declarations instead of definitions per LWG issue 2340.
8964 // Suppress the diagnostic if the function is __attribute__((used)), since
8965 // that forces an external definition to be emitted.
8966 if (D.getDeclSpec().isInlineSpecified() &&
8967 NewFD->isReplaceableGlobalAllocationFunction() &&
8968 !NewFD->hasAttr<UsedAttr>())
8969 Diag(D.getDeclSpec().getInlineSpecLoc(),
8970 diag::ext_operator_new_delete_declared_inline)
8971 << NewFD->getDeclName();
8973 // If the declarator is a template-id, translate the parser's template
8974 // argument list into our AST format.
8975 if (D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId) {
8976 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
8977 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
8978 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
8979 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
8980 TemplateId->NumArgs);
8981 translateTemplateArguments(TemplateArgsPtr,
8984 HasExplicitTemplateArgs = true;
8986 if (NewFD->isInvalidDecl()) {
8987 HasExplicitTemplateArgs = false;
8988 } else if (FunctionTemplate) {
8989 // Function template with explicit template arguments.
8990 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec)
8991 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc);
8993 HasExplicitTemplateArgs = false;
8995 assert((isFunctionTemplateSpecialization ||
8996 D.getDeclSpec().isFriendSpecified()) &&
8997 "should have a 'template<>' for this decl");
8998 // "friend void foo<>(int);" is an implicit specialization decl.
8999 isFunctionTemplateSpecialization = true;
9001 } else if (isFriend && isFunctionTemplateSpecialization) {
9002 // This combination is only possible in a recovery case; the user
9003 // wrote something like:
9004 // template <> friend void foo(int);
9005 // which we're recovering from as if the user had written:
9006 // friend void foo<>(int);
9007 // Go ahead and fake up a template id.
9008 HasExplicitTemplateArgs = true;
9009 TemplateArgs.setLAngleLoc(D.getIdentifierLoc());
9010 TemplateArgs.setRAngleLoc(D.getIdentifierLoc());
9013 // We do not add HD attributes to specializations here because
9014 // they may have different constexpr-ness compared to their
9015 // templates and, after maybeAddCUDAHostDeviceAttrs() is applied,
9016 // may end up with different effective targets. Instead, a
9017 // specialization inherits its target attributes from its template
9018 // in the CheckFunctionTemplateSpecialization() call below.
9019 if (getLangOpts().CUDA & !isFunctionTemplateSpecialization)
9020 maybeAddCUDAHostDeviceAttrs(NewFD, Previous);
9022 // If it's a friend (and only if it's a friend), it's possible
9023 // that either the specialized function type or the specialized
9024 // template is dependent, and therefore matching will fail. In
9025 // this case, don't check the specialization yet.
9026 bool InstantiationDependent = false;
9027 if (isFunctionTemplateSpecialization && isFriend &&
9028 (NewFD->getType()->isDependentType() || DC->isDependentContext() ||
9029 TemplateSpecializationType::anyDependentTemplateArguments(
9031 InstantiationDependent))) {
9032 assert(HasExplicitTemplateArgs &&
9033 "friend function specialization without template args");
9034 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs,
9036 NewFD->setInvalidDecl();
9037 } else if (isFunctionTemplateSpecialization) {
9038 if (CurContext->isDependentContext() && CurContext->isRecord()
9040 isDependentClassScopeExplicitSpecialization = true;
9041 } else if (!NewFD->isInvalidDecl() &&
9042 CheckFunctionTemplateSpecialization(
9043 NewFD, (HasExplicitTemplateArgs ? &TemplateArgs : nullptr),
9045 NewFD->setInvalidDecl();
9048 // A storage-class-specifier shall not be specified in an explicit
9049 // specialization (14.7.3)
9050 FunctionTemplateSpecializationInfo *Info =
9051 NewFD->getTemplateSpecializationInfo();
9052 if (Info && SC != SC_None) {
9053 if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass())
9054 Diag(NewFD->getLocation(),
9055 diag::err_explicit_specialization_inconsistent_storage_class)
9057 << FixItHint::CreateRemoval(
9058 D.getDeclSpec().getStorageClassSpecLoc());
9061 Diag(NewFD->getLocation(),
9062 diag::ext_explicit_specialization_storage_class)
9063 << FixItHint::CreateRemoval(
9064 D.getDeclSpec().getStorageClassSpecLoc());
9066 } else if (isMemberSpecialization && isa<CXXMethodDecl>(NewFD)) {
9067 if (CheckMemberSpecialization(NewFD, Previous))
9068 NewFD->setInvalidDecl();
9071 // Perform semantic checking on the function declaration.
9072 if (!isDependentClassScopeExplicitSpecialization) {
9073 if (!NewFD->isInvalidDecl() && NewFD->isMain())
9074 CheckMain(NewFD, D.getDeclSpec());
9076 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
9077 CheckMSVCRTEntryPoint(NewFD);
9079 if (!NewFD->isInvalidDecl())
9080 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
9081 isMemberSpecialization));
9082 else if (!Previous.empty())
9083 // Recover gracefully from an invalid redeclaration.
9084 D.setRedeclaration(true);
9087 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
9088 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
9089 "previous declaration set still overloaded");
9091 NamedDecl *PrincipalDecl = (FunctionTemplate
9092 ? cast<NamedDecl>(FunctionTemplate)
9095 if (isFriend && NewFD->getPreviousDecl()) {
9096 AccessSpecifier Access = AS_public;
9097 if (!NewFD->isInvalidDecl())
9098 Access = NewFD->getPreviousDecl()->getAccess();
9100 NewFD->setAccess(Access);
9101 if (FunctionTemplate) FunctionTemplate->setAccess(Access);
9104 if (NewFD->isOverloadedOperator() && !DC->isRecord() &&
9105 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
9106 PrincipalDecl->setNonMemberOperator();
9108 // If we have a function template, check the template parameter
9109 // list. This will check and merge default template arguments.
9110 if (FunctionTemplate) {
9111 FunctionTemplateDecl *PrevTemplate =
9112 FunctionTemplate->getPreviousDecl();
9113 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(),
9114 PrevTemplate ? PrevTemplate->getTemplateParameters()
9116 D.getDeclSpec().isFriendSpecified()
9117 ? (D.isFunctionDefinition()
9118 ? TPC_FriendFunctionTemplateDefinition
9119 : TPC_FriendFunctionTemplate)
9120 : (D.getCXXScopeSpec().isSet() &&
9121 DC && DC->isRecord() &&
9122 DC->isDependentContext())
9123 ? TPC_ClassTemplateMember
9124 : TPC_FunctionTemplate);
9127 if (NewFD->isInvalidDecl()) {
9128 // Ignore all the rest of this.
9129 } else if (!D.isRedeclaration()) {
9130 struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists,
9132 // Fake up an access specifier if it's supposed to be a class member.
9133 if (isa<CXXRecordDecl>(NewFD->getDeclContext()))
9134 NewFD->setAccess(AS_public);
9136 // Qualified decls generally require a previous declaration.
9137 if (D.getCXXScopeSpec().isSet()) {
9138 // ...with the major exception of templated-scope or
9139 // dependent-scope friend declarations.
9141 // TODO: we currently also suppress this check in dependent
9142 // contexts because (1) the parameter depth will be off when
9143 // matching friend templates and (2) we might actually be
9144 // selecting a friend based on a dependent factor. But there
9145 // are situations where these conditions don't apply and we
9146 // can actually do this check immediately.
9148 // Unless the scope is dependent, it's always an error if qualified
9149 // redeclaration lookup found nothing at all. Diagnose that now;
9150 // nothing will diagnose that error later.
9152 (D.getCXXScopeSpec().getScopeRep()->isDependent() ||
9153 (!Previous.empty() && CurContext->isDependentContext()))) {
9156 // The user tried to provide an out-of-line definition for a
9157 // function that is a member of a class or namespace, but there
9158 // was no such member function declared (C++ [class.mfct]p2,
9159 // C++ [namespace.memdef]p2). For example:
9165 // void X::f() { } // ill-formed
9167 // Complain about this problem, and attempt to suggest close
9168 // matches (e.g., those that differ only in cv-qualifiers and
9169 // whether the parameter types are references).
9171 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
9172 *this, Previous, NewFD, ExtraArgs, false, nullptr)) {
9173 AddToScope = ExtraArgs.AddToScope;
9178 // Unqualified local friend declarations are required to resolve
9180 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) {
9181 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
9182 *this, Previous, NewFD, ExtraArgs, true, S)) {
9183 AddToScope = ExtraArgs.AddToScope;
9187 } else if (!D.isFunctionDefinition() &&
9188 isa<CXXMethodDecl>(NewFD) && NewFD->isOutOfLine() &&
9189 !isFriend && !isFunctionTemplateSpecialization &&
9190 !isMemberSpecialization) {
9191 // An out-of-line member function declaration must also be a
9192 // definition (C++ [class.mfct]p2).
9193 // Note that this is not the case for explicit specializations of
9194 // function templates or member functions of class templates, per
9195 // C++ [temp.expl.spec]p2. We also allow these declarations as an
9196 // extension for compatibility with old SWIG code which likes to
9198 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration)
9199 << D.getCXXScopeSpec().getRange();
9203 ProcessPragmaWeak(S, NewFD);
9204 checkAttributesAfterMerging(*this, *NewFD);
9206 AddKnownFunctionAttributes(NewFD);
9208 if (NewFD->hasAttr<OverloadableAttr>() &&
9209 !NewFD->getType()->getAs<FunctionProtoType>()) {
9210 Diag(NewFD->getLocation(),
9211 diag::err_attribute_overloadable_no_prototype)
9214 // Turn this into a variadic function with no parameters.
9215 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>();
9216 FunctionProtoType::ExtProtoInfo EPI(
9217 Context.getDefaultCallingConvention(true, false));
9218 EPI.Variadic = true;
9219 EPI.ExtInfo = FT->getExtInfo();
9221 QualType R = Context.getFunctionType(FT->getReturnType(), None, EPI);
9225 // If there's a #pragma GCC visibility in scope, and this isn't a class
9226 // member, set the visibility of this function.
9227 if (!DC->isRecord() && NewFD->isExternallyVisible())
9228 AddPushedVisibilityAttribute(NewFD);
9230 // If there's a #pragma clang arc_cf_code_audited in scope, consider
9231 // marking the function.
9232 AddCFAuditedAttribute(NewFD);
9234 // If this is a function definition, check if we have to apply optnone due to
9236 if(D.isFunctionDefinition())
9237 AddRangeBasedOptnone(NewFD);
9239 // If this is the first declaration of an extern C variable, update
9240 // the map of such variables.
9241 if (NewFD->isFirstDecl() && !NewFD->isInvalidDecl() &&
9242 isIncompleteDeclExternC(*this, NewFD))
9243 RegisterLocallyScopedExternCDecl(NewFD, S);
9245 // Set this FunctionDecl's range up to the right paren.
9246 NewFD->setRangeEnd(D.getSourceRange().getEnd());
9248 if (D.isRedeclaration() && !Previous.empty()) {
9249 NamedDecl *Prev = Previous.getRepresentativeDecl();
9250 checkDLLAttributeRedeclaration(*this, Prev, NewFD,
9251 isMemberSpecialization ||
9252 isFunctionTemplateSpecialization,
9253 D.isFunctionDefinition());
9256 if (getLangOpts().CUDA) {
9257 IdentifierInfo *II = NewFD->getIdentifier();
9258 if (II && II->isStr(getCudaConfigureFuncName()) &&
9259 !NewFD->isInvalidDecl() &&
9260 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
9261 if (!R->getAs<FunctionType>()->getReturnType()->isScalarType())
9262 Diag(NewFD->getLocation(), diag::err_config_scalar_return)
9263 << getCudaConfigureFuncName();
9264 Context.setcudaConfigureCallDecl(NewFD);
9267 // Variadic functions, other than a *declaration* of printf, are not allowed
9268 // in device-side CUDA code, unless someone passed
9269 // -fcuda-allow-variadic-functions.
9270 if (!getLangOpts().CUDAAllowVariadicFunctions && NewFD->isVariadic() &&
9271 (NewFD->hasAttr<CUDADeviceAttr>() ||
9272 NewFD->hasAttr<CUDAGlobalAttr>()) &&
9273 !(II && II->isStr("printf") && NewFD->isExternC() &&
9274 !D.isFunctionDefinition())) {
9275 Diag(NewFD->getLocation(), diag::err_variadic_device_fn);
9279 MarkUnusedFileScopedDecl(NewFD);
9283 if (getLangOpts().OpenCL && NewFD->hasAttr<OpenCLKernelAttr>()) {
9284 // OpenCL v1.2 s6.8 static is invalid for kernel functions.
9285 if ((getLangOpts().OpenCLVersion >= 120)
9286 && (SC == SC_Static)) {
9287 Diag(D.getIdentifierLoc(), diag::err_static_kernel);
9291 // OpenCL v1.2, s6.9 -- Kernels can only have return type void.
9292 if (!NewFD->getReturnType()->isVoidType()) {
9293 SourceRange RTRange = NewFD->getReturnTypeSourceRange();
9294 Diag(D.getIdentifierLoc(), diag::err_expected_kernel_void_return_type)
9295 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "void")
9300 llvm::SmallPtrSet<const Type *, 16> ValidTypes;
9301 for (auto Param : NewFD->parameters())
9302 checkIsValidOpenCLKernelParameter(*this, D, Param, ValidTypes);
9304 if (getLangOpts().OpenCLCPlusPlus) {
9305 if (DC->isRecord()) {
9306 Diag(D.getIdentifierLoc(), diag::err_method_kernel);
9309 if (FunctionTemplate) {
9310 Diag(D.getIdentifierLoc(), diag::err_template_kernel);
9316 if (getLangOpts().CPlusPlus) {
9317 if (FunctionTemplate) {
9318 if (NewFD->isInvalidDecl())
9319 FunctionTemplate->setInvalidDecl();
9320 return FunctionTemplate;
9323 if (isMemberSpecialization && !NewFD->isInvalidDecl())
9324 CompleteMemberSpecialization(NewFD, Previous);
9327 for (const ParmVarDecl *Param : NewFD->parameters()) {
9328 QualType PT = Param->getType();
9330 // OpenCL 2.0 pipe restrictions forbids pipe packet types to be non-value
9332 if (getLangOpts().OpenCLVersion >= 200 || getLangOpts().OpenCLCPlusPlus) {
9333 if(const PipeType *PipeTy = PT->getAs<PipeType>()) {
9334 QualType ElemTy = PipeTy->getElementType();
9335 if (ElemTy->isReferenceType() || ElemTy->isPointerType()) {
9336 Diag(Param->getTypeSpecStartLoc(), diag::err_reference_pipe_type );
9343 // Here we have an function template explicit specialization at class scope.
9344 // The actual specialization will be postponed to template instatiation
9345 // time via the ClassScopeFunctionSpecializationDecl node.
9346 if (isDependentClassScopeExplicitSpecialization) {
9347 ClassScopeFunctionSpecializationDecl *NewSpec =
9348 ClassScopeFunctionSpecializationDecl::Create(
9349 Context, CurContext, NewFD->getLocation(),
9350 cast<CXXMethodDecl>(NewFD),
9351 HasExplicitTemplateArgs, TemplateArgs);
9352 CurContext->addDecl(NewSpec);
9356 // Diagnose availability attributes. Availability cannot be used on functions
9357 // that are run during load/unload.
9358 if (const auto *attr = NewFD->getAttr<AvailabilityAttr>()) {
9359 if (NewFD->hasAttr<ConstructorAttr>()) {
9360 Diag(attr->getLocation(), diag::warn_availability_on_static_initializer)
9362 NewFD->dropAttr<AvailabilityAttr>();
9364 if (NewFD->hasAttr<DestructorAttr>()) {
9365 Diag(attr->getLocation(), diag::warn_availability_on_static_initializer)
9367 NewFD->dropAttr<AvailabilityAttr>();
9374 /// Return a CodeSegAttr from a containing class. The Microsoft docs say
9375 /// when __declspec(code_seg) "is applied to a class, all member functions of
9376 /// the class and nested classes -- this includes compiler-generated special
9377 /// member functions -- are put in the specified segment."
9378 /// The actual behavior is a little more complicated. The Microsoft compiler
9379 /// won't check outer classes if there is an active value from #pragma code_seg.
9380 /// The CodeSeg is always applied from the direct parent but only from outer
9381 /// classes when the #pragma code_seg stack is empty. See:
9382 /// https://reviews.llvm.org/D22931, the Microsoft feedback page is no longer
9383 /// available since MS has removed the page.
9384 static Attr *getImplicitCodeSegAttrFromClass(Sema &S, const FunctionDecl *FD) {
9385 const auto *Method = dyn_cast<CXXMethodDecl>(FD);
9388 const CXXRecordDecl *Parent = Method->getParent();
9389 if (const auto *SAttr = Parent->getAttr<CodeSegAttr>()) {
9390 Attr *NewAttr = SAttr->clone(S.getASTContext());
9391 NewAttr->setImplicit(true);
9395 // The Microsoft compiler won't check outer classes for the CodeSeg
9396 // when the #pragma code_seg stack is active.
9397 if (S.CodeSegStack.CurrentValue)
9400 while ((Parent = dyn_cast<CXXRecordDecl>(Parent->getParent()))) {
9401 if (const auto *SAttr = Parent->getAttr<CodeSegAttr>()) {
9402 Attr *NewAttr = SAttr->clone(S.getASTContext());
9403 NewAttr->setImplicit(true);
9410 /// Returns an implicit CodeSegAttr if a __declspec(code_seg) is found on a
9411 /// containing class. Otherwise it will return implicit SectionAttr if the
9412 /// function is a definition and there is an active value on CodeSegStack
9413 /// (from the current #pragma code-seg value).
9415 /// \param FD Function being declared.
9416 /// \param IsDefinition Whether it is a definition or just a declarartion.
9417 /// \returns A CodeSegAttr or SectionAttr to apply to the function or
9418 /// nullptr if no attribute should be added.
9419 Attr *Sema::getImplicitCodeSegOrSectionAttrForFunction(const FunctionDecl *FD,
9420 bool IsDefinition) {
9421 if (Attr *A = getImplicitCodeSegAttrFromClass(*this, FD))
9423 if (!FD->hasAttr<SectionAttr>() && IsDefinition &&
9424 CodeSegStack.CurrentValue) {
9425 return SectionAttr::CreateImplicit(getASTContext(),
9426 SectionAttr::Declspec_allocate,
9427 CodeSegStack.CurrentValue->getString(),
9428 CodeSegStack.CurrentPragmaLocation);
9433 /// Determines if we can perform a correct type check for \p D as a
9434 /// redeclaration of \p PrevDecl. If not, we can generally still perform a
9435 /// best-effort check.
9437 /// \param NewD The new declaration.
9438 /// \param OldD The old declaration.
9439 /// \param NewT The portion of the type of the new declaration to check.
9440 /// \param OldT The portion of the type of the old declaration to check.
9441 bool Sema::canFullyTypeCheckRedeclaration(ValueDecl *NewD, ValueDecl *OldD,
9442 QualType NewT, QualType OldT) {
9443 if (!NewD->getLexicalDeclContext()->isDependentContext())
9446 // For dependently-typed local extern declarations and friends, we can't
9447 // perform a correct type check in general until instantiation:
9450 // template<typename T> void g() { T f(); }
9452 // (valid if g() is only instantiated with T = int).
9453 if (NewT->isDependentType() &&
9454 (NewD->isLocalExternDecl() || NewD->getFriendObjectKind()))
9457 // Similarly, if the previous declaration was a dependent local extern
9458 // declaration, we don't really know its type yet.
9459 if (OldT->isDependentType() && OldD->isLocalExternDecl())
9465 /// Checks if the new declaration declared in dependent context must be
9466 /// put in the same redeclaration chain as the specified declaration.
9468 /// \param D Declaration that is checked.
9469 /// \param PrevDecl Previous declaration found with proper lookup method for the
9470 /// same declaration name.
9471 /// \returns True if D must be added to the redeclaration chain which PrevDecl
9474 bool Sema::shouldLinkDependentDeclWithPrevious(Decl *D, Decl *PrevDecl) {
9475 if (!D->getLexicalDeclContext()->isDependentContext())
9478 // Don't chain dependent friend function definitions until instantiation, to
9479 // permit cases like
9482 // template<typename T> class C1 { friend void func() {} };
9483 // template<typename T> class C2 { friend void func() {} };
9485 // ... which is valid if only one of C1 and C2 is ever instantiated.
9487 // FIXME: This need only apply to function definitions. For now, we proxy
9488 // this by checking for a file-scope function. We do not want this to apply
9489 // to friend declarations nominating member functions, because that gets in
9490 // the way of access checks.
9491 if (D->getFriendObjectKind() && D->getDeclContext()->isFileContext())
9494 auto *VD = dyn_cast<ValueDecl>(D);
9495 auto *PrevVD = dyn_cast<ValueDecl>(PrevDecl);
9496 return !VD || !PrevVD ||
9497 canFullyTypeCheckRedeclaration(VD, PrevVD, VD->getType(),
9501 /// Check the target attribute of the function for MultiVersion
9504 /// Returns true if there was an error, false otherwise.
9505 static bool CheckMultiVersionValue(Sema &S, const FunctionDecl *FD) {
9506 const auto *TA = FD->getAttr<TargetAttr>();
9507 assert(TA && "MultiVersion Candidate requires a target attribute");
9508 TargetAttr::ParsedTargetAttr ParseInfo = TA->parse();
9509 const TargetInfo &TargetInfo = S.Context.getTargetInfo();
9510 enum ErrType { Feature = 0, Architecture = 1 };
9512 if (!ParseInfo.Architecture.empty() &&
9513 !TargetInfo.validateCpuIs(ParseInfo.Architecture)) {
9514 S.Diag(FD->getLocation(), diag::err_bad_multiversion_option)
9515 << Architecture << ParseInfo.Architecture;
9519 for (const auto &Feat : ParseInfo.Features) {
9520 auto BareFeat = StringRef{Feat}.substr(1);
9521 if (Feat[0] == '-') {
9522 S.Diag(FD->getLocation(), diag::err_bad_multiversion_option)
9523 << Feature << ("no-" + BareFeat).str();
9527 if (!TargetInfo.validateCpuSupports(BareFeat) ||
9528 !TargetInfo.isValidFeatureName(BareFeat)) {
9529 S.Diag(FD->getLocation(), diag::err_bad_multiversion_option)
9530 << Feature << BareFeat;
9537 static bool HasNonMultiVersionAttributes(const FunctionDecl *FD,
9538 MultiVersionKind MVType) {
9539 for (const Attr *A : FD->attrs()) {
9540 switch (A->getKind()) {
9541 case attr::CPUDispatch:
9542 case attr::CPUSpecific:
9543 if (MVType != MultiVersionKind::CPUDispatch &&
9544 MVType != MultiVersionKind::CPUSpecific)
9548 if (MVType != MultiVersionKind::Target)
9558 static bool CheckMultiVersionAdditionalRules(Sema &S, const FunctionDecl *OldFD,
9559 const FunctionDecl *NewFD,
9561 MultiVersionKind MVType) {
9562 enum DoesntSupport {
9582 bool IsCPUSpecificCPUDispatchMVType =
9583 MVType == MultiVersionKind::CPUDispatch ||
9584 MVType == MultiVersionKind::CPUSpecific;
9586 if (OldFD && !OldFD->getType()->getAs<FunctionProtoType>()) {
9587 S.Diag(OldFD->getLocation(), diag::err_multiversion_noproto);
9588 S.Diag(NewFD->getLocation(), diag::note_multiversioning_caused_here);
9592 if (!NewFD->getType()->getAs<FunctionProtoType>())
9593 return S.Diag(NewFD->getLocation(), diag::err_multiversion_noproto);
9595 if (!S.getASTContext().getTargetInfo().supportsMultiVersioning()) {
9596 S.Diag(NewFD->getLocation(), diag::err_multiversion_not_supported);
9598 S.Diag(OldFD->getLocation(), diag::note_previous_declaration);
9602 // For now, disallow all other attributes. These should be opt-in, but
9603 // an analysis of all of them is a future FIXME.
9604 if (CausesMV && OldFD && HasNonMultiVersionAttributes(OldFD, MVType)) {
9605 S.Diag(OldFD->getLocation(), diag::err_multiversion_no_other_attrs)
9606 << IsCPUSpecificCPUDispatchMVType;
9607 S.Diag(NewFD->getLocation(), diag::note_multiversioning_caused_here);
9611 if (HasNonMultiVersionAttributes(NewFD, MVType))
9612 return S.Diag(NewFD->getLocation(), diag::err_multiversion_no_other_attrs)
9613 << IsCPUSpecificCPUDispatchMVType;
9615 if (NewFD->getTemplatedKind() == FunctionDecl::TK_FunctionTemplate)
9616 return S.Diag(NewFD->getLocation(), diag::err_multiversion_doesnt_support)
9617 << IsCPUSpecificCPUDispatchMVType << FuncTemplates;
9619 if (const auto *NewCXXFD = dyn_cast<CXXMethodDecl>(NewFD)) {
9620 if (NewCXXFD->isVirtual())
9621 return S.Diag(NewCXXFD->getLocation(),
9622 diag::err_multiversion_doesnt_support)
9623 << IsCPUSpecificCPUDispatchMVType << VirtFuncs;
9625 if (const auto *NewCXXCtor = dyn_cast<CXXConstructorDecl>(NewFD))
9626 return S.Diag(NewCXXCtor->getLocation(),
9627 diag::err_multiversion_doesnt_support)
9628 << IsCPUSpecificCPUDispatchMVType << Constructors;
9630 if (const auto *NewCXXDtor = dyn_cast<CXXDestructorDecl>(NewFD))
9631 return S.Diag(NewCXXDtor->getLocation(),
9632 diag::err_multiversion_doesnt_support)
9633 << IsCPUSpecificCPUDispatchMVType << Destructors;
9636 if (NewFD->isDeleted())
9637 return S.Diag(NewFD->getLocation(), diag::err_multiversion_doesnt_support)
9638 << IsCPUSpecificCPUDispatchMVType << DeletedFuncs;
9640 if (NewFD->isDefaulted())
9641 return S.Diag(NewFD->getLocation(), diag::err_multiversion_doesnt_support)
9642 << IsCPUSpecificCPUDispatchMVType << DefaultedFuncs;
9644 if (NewFD->isConstexpr() && (MVType == MultiVersionKind::CPUDispatch ||
9645 MVType == MultiVersionKind::CPUSpecific))
9646 return S.Diag(NewFD->getLocation(), diag::err_multiversion_doesnt_support)
9647 << IsCPUSpecificCPUDispatchMVType
9648 << (NewFD->isConsteval() ? ConstevalFuncs : ConstexprFuncs);
9650 QualType NewQType = S.getASTContext().getCanonicalType(NewFD->getType());
9651 const auto *NewType = cast<FunctionType>(NewQType);
9652 QualType NewReturnType = NewType->getReturnType();
9654 if (NewReturnType->isUndeducedType())
9655 return S.Diag(NewFD->getLocation(), diag::err_multiversion_doesnt_support)
9656 << IsCPUSpecificCPUDispatchMVType << DeducedReturn;
9658 // Only allow transition to MultiVersion if it hasn't been used.
9659 if (OldFD && CausesMV && OldFD->isUsed(false))
9660 return S.Diag(NewFD->getLocation(), diag::err_multiversion_after_used);
9662 // Ensure the return type is identical.
9664 QualType OldQType = S.getASTContext().getCanonicalType(OldFD->getType());
9665 const auto *OldType = cast<FunctionType>(OldQType);
9666 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo();
9667 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo();
9669 if (OldTypeInfo.getCC() != NewTypeInfo.getCC())
9670 return S.Diag(NewFD->getLocation(), diag::err_multiversion_diff)
9673 QualType OldReturnType = OldType->getReturnType();
9675 if (OldReturnType != NewReturnType)
9676 return S.Diag(NewFD->getLocation(), diag::err_multiversion_diff)
9679 if (OldFD->getConstexprKind() != NewFD->getConstexprKind())
9680 return S.Diag(NewFD->getLocation(), diag::err_multiversion_diff)
9683 if (OldFD->isInlineSpecified() != NewFD->isInlineSpecified())
9684 return S.Diag(NewFD->getLocation(), diag::err_multiversion_diff)
9687 if (OldFD->getStorageClass() != NewFD->getStorageClass())
9688 return S.Diag(NewFD->getLocation(), diag::err_multiversion_diff)
9691 if (OldFD->isExternC() != NewFD->isExternC())
9692 return S.Diag(NewFD->getLocation(), diag::err_multiversion_diff)
9695 if (S.CheckEquivalentExceptionSpec(
9696 OldFD->getType()->getAs<FunctionProtoType>(), OldFD->getLocation(),
9697 NewFD->getType()->getAs<FunctionProtoType>(), NewFD->getLocation()))
9703 /// Check the validity of a multiversion function declaration that is the
9704 /// first of its kind. Also sets the multiversion'ness' of the function itself.
9706 /// This sets NewFD->isInvalidDecl() to true if there was an error.
9708 /// Returns true if there was an error, false otherwise.
9709 static bool CheckMultiVersionFirstFunction(Sema &S, FunctionDecl *FD,
9710 MultiVersionKind MVType,
9711 const TargetAttr *TA) {
9712 assert(MVType != MultiVersionKind::None &&
9713 "Function lacks multiversion attribute");
9715 // Target only causes MV if it is default, otherwise this is a normal
9717 if (MVType == MultiVersionKind::Target && !TA->isDefaultVersion())
9720 if (MVType == MultiVersionKind::Target && CheckMultiVersionValue(S, FD)) {
9721 FD->setInvalidDecl();
9725 if (CheckMultiVersionAdditionalRules(S, nullptr, FD, true, MVType)) {
9726 FD->setInvalidDecl();
9730 FD->setIsMultiVersion();
9734 static bool PreviousDeclsHaveMultiVersionAttribute(const FunctionDecl *FD) {
9735 for (const Decl *D = FD->getPreviousDecl(); D; D = D->getPreviousDecl()) {
9736 if (D->getAsFunction()->getMultiVersionKind() != MultiVersionKind::None)
9743 static bool CheckTargetCausesMultiVersioning(
9744 Sema &S, FunctionDecl *OldFD, FunctionDecl *NewFD, const TargetAttr *NewTA,
9745 bool &Redeclaration, NamedDecl *&OldDecl, bool &MergeTypeWithPrevious,
9746 LookupResult &Previous) {
9747 const auto *OldTA = OldFD->getAttr<TargetAttr>();
9748 TargetAttr::ParsedTargetAttr NewParsed = NewTA->parse();
9749 // Sort order doesn't matter, it just needs to be consistent.
9750 llvm::sort(NewParsed.Features);
9752 // If the old decl is NOT MultiVersioned yet, and we don't cause that
9753 // to change, this is a simple redeclaration.
9754 if (!NewTA->isDefaultVersion() &&
9755 (!OldTA || OldTA->getFeaturesStr() == NewTA->getFeaturesStr()))
9758 // Otherwise, this decl causes MultiVersioning.
9759 if (!S.getASTContext().getTargetInfo().supportsMultiVersioning()) {
9760 S.Diag(NewFD->getLocation(), diag::err_multiversion_not_supported);
9761 S.Diag(OldFD->getLocation(), diag::note_previous_declaration);
9762 NewFD->setInvalidDecl();
9766 if (CheckMultiVersionAdditionalRules(S, OldFD, NewFD, true,
9767 MultiVersionKind::Target)) {
9768 NewFD->setInvalidDecl();
9772 if (CheckMultiVersionValue(S, NewFD)) {
9773 NewFD->setInvalidDecl();
9777 // If this is 'default', permit the forward declaration.
9778 if (!OldFD->isMultiVersion() && !OldTA && NewTA->isDefaultVersion()) {
9779 Redeclaration = true;
9781 OldFD->setIsMultiVersion();
9782 NewFD->setIsMultiVersion();
9786 if (CheckMultiVersionValue(S, OldFD)) {
9787 S.Diag(NewFD->getLocation(), diag::note_multiversioning_caused_here);
9788 NewFD->setInvalidDecl();
9792 TargetAttr::ParsedTargetAttr OldParsed =
9793 OldTA->parse(std::less<std::string>());
9795 if (OldParsed == NewParsed) {
9796 S.Diag(NewFD->getLocation(), diag::err_multiversion_duplicate);
9797 S.Diag(OldFD->getLocation(), diag::note_previous_declaration);
9798 NewFD->setInvalidDecl();
9802 for (const auto *FD : OldFD->redecls()) {
9803 const auto *CurTA = FD->getAttr<TargetAttr>();
9804 // We allow forward declarations before ANY multiversioning attributes, but
9805 // nothing after the fact.
9806 if (PreviousDeclsHaveMultiVersionAttribute(FD) &&
9807 (!CurTA || CurTA->isInherited())) {
9808 S.Diag(FD->getLocation(), diag::err_multiversion_required_in_redecl)
9810 S.Diag(NewFD->getLocation(), diag::note_multiversioning_caused_here);
9811 NewFD->setInvalidDecl();
9816 OldFD->setIsMultiVersion();
9817 NewFD->setIsMultiVersion();
9818 Redeclaration = false;
9819 MergeTypeWithPrevious = false;
9825 /// Check the validity of a new function declaration being added to an existing
9826 /// multiversioned declaration collection.
9827 static bool CheckMultiVersionAdditionalDecl(
9828 Sema &S, FunctionDecl *OldFD, FunctionDecl *NewFD,
9829 MultiVersionKind NewMVType, const TargetAttr *NewTA,
9830 const CPUDispatchAttr *NewCPUDisp, const CPUSpecificAttr *NewCPUSpec,
9831 bool &Redeclaration, NamedDecl *&OldDecl, bool &MergeTypeWithPrevious,
9832 LookupResult &Previous) {
9834 MultiVersionKind OldMVType = OldFD->getMultiVersionKind();
9835 // Disallow mixing of multiversioning types.
9836 if ((OldMVType == MultiVersionKind::Target &&
9837 NewMVType != MultiVersionKind::Target) ||
9838 (NewMVType == MultiVersionKind::Target &&
9839 OldMVType != MultiVersionKind::Target)) {
9840 S.Diag(NewFD->getLocation(), diag::err_multiversion_types_mixed);
9841 S.Diag(OldFD->getLocation(), diag::note_previous_declaration);
9842 NewFD->setInvalidDecl();
9846 TargetAttr::ParsedTargetAttr NewParsed;
9848 NewParsed = NewTA->parse();
9849 llvm::sort(NewParsed.Features);
9852 bool UseMemberUsingDeclRules =
9853 S.CurContext->isRecord() && !NewFD->getFriendObjectKind();
9855 // Next, check ALL non-overloads to see if this is a redeclaration of a
9856 // previous member of the MultiVersion set.
9857 for (NamedDecl *ND : Previous) {
9858 FunctionDecl *CurFD = ND->getAsFunction();
9861 if (S.IsOverload(NewFD, CurFD, UseMemberUsingDeclRules))
9864 if (NewMVType == MultiVersionKind::Target) {
9865 const auto *CurTA = CurFD->getAttr<TargetAttr>();
9866 if (CurTA->getFeaturesStr() == NewTA->getFeaturesStr()) {
9867 NewFD->setIsMultiVersion();
9868 Redeclaration = true;
9873 TargetAttr::ParsedTargetAttr CurParsed =
9874 CurTA->parse(std::less<std::string>());
9875 if (CurParsed == NewParsed) {
9876 S.Diag(NewFD->getLocation(), diag::err_multiversion_duplicate);
9877 S.Diag(CurFD->getLocation(), diag::note_previous_declaration);
9878 NewFD->setInvalidDecl();
9882 const auto *CurCPUSpec = CurFD->getAttr<CPUSpecificAttr>();
9883 const auto *CurCPUDisp = CurFD->getAttr<CPUDispatchAttr>();
9884 // Handle CPUDispatch/CPUSpecific versions.
9885 // Only 1 CPUDispatch function is allowed, this will make it go through
9886 // the redeclaration errors.
9887 if (NewMVType == MultiVersionKind::CPUDispatch &&
9888 CurFD->hasAttr<CPUDispatchAttr>()) {
9889 if (CurCPUDisp->cpus_size() == NewCPUDisp->cpus_size() &&
9891 CurCPUDisp->cpus_begin(), CurCPUDisp->cpus_end(),
9892 NewCPUDisp->cpus_begin(),
9893 [](const IdentifierInfo *Cur, const IdentifierInfo *New) {
9894 return Cur->getName() == New->getName();
9896 NewFD->setIsMultiVersion();
9897 Redeclaration = true;
9902 // If the declarations don't match, this is an error condition.
9903 S.Diag(NewFD->getLocation(), diag::err_cpu_dispatch_mismatch);
9904 S.Diag(CurFD->getLocation(), diag::note_previous_declaration);
9905 NewFD->setInvalidDecl();
9908 if (NewMVType == MultiVersionKind::CPUSpecific && CurCPUSpec) {
9910 if (CurCPUSpec->cpus_size() == NewCPUSpec->cpus_size() &&
9912 CurCPUSpec->cpus_begin(), CurCPUSpec->cpus_end(),
9913 NewCPUSpec->cpus_begin(),
9914 [](const IdentifierInfo *Cur, const IdentifierInfo *New) {
9915 return Cur->getName() == New->getName();
9917 NewFD->setIsMultiVersion();
9918 Redeclaration = true;
9923 // Only 1 version of CPUSpecific is allowed for each CPU.
9924 for (const IdentifierInfo *CurII : CurCPUSpec->cpus()) {
9925 for (const IdentifierInfo *NewII : NewCPUSpec->cpus()) {
9926 if (CurII == NewII) {
9927 S.Diag(NewFD->getLocation(), diag::err_cpu_specific_multiple_defs)
9929 S.Diag(CurFD->getLocation(), diag::note_previous_declaration);
9930 NewFD->setInvalidDecl();
9936 // If the two decls aren't the same MVType, there is no possible error
9941 // Else, this is simply a non-redecl case. Checking the 'value' is only
9942 // necessary in the Target case, since The CPUSpecific/Dispatch cases are
9943 // handled in the attribute adding step.
9944 if (NewMVType == MultiVersionKind::Target &&
9945 CheckMultiVersionValue(S, NewFD)) {
9946 NewFD->setInvalidDecl();
9950 if (CheckMultiVersionAdditionalRules(S, OldFD, NewFD,
9951 !OldFD->isMultiVersion(), NewMVType)) {
9952 NewFD->setInvalidDecl();
9956 // Permit forward declarations in the case where these two are compatible.
9957 if (!OldFD->isMultiVersion()) {
9958 OldFD->setIsMultiVersion();
9959 NewFD->setIsMultiVersion();
9960 Redeclaration = true;
9965 NewFD->setIsMultiVersion();
9966 Redeclaration = false;
9967 MergeTypeWithPrevious = false;
9974 /// Check the validity of a mulitversion function declaration.
9975 /// Also sets the multiversion'ness' of the function itself.
9977 /// This sets NewFD->isInvalidDecl() to true if there was an error.
9979 /// Returns true if there was an error, false otherwise.
9980 static bool CheckMultiVersionFunction(Sema &S, FunctionDecl *NewFD,
9981 bool &Redeclaration, NamedDecl *&OldDecl,
9982 bool &MergeTypeWithPrevious,
9983 LookupResult &Previous) {
9984 const auto *NewTA = NewFD->getAttr<TargetAttr>();
9985 const auto *NewCPUDisp = NewFD->getAttr<CPUDispatchAttr>();
9986 const auto *NewCPUSpec = NewFD->getAttr<CPUSpecificAttr>();
9988 // Mixing Multiversioning types is prohibited.
9989 if ((NewTA && NewCPUDisp) || (NewTA && NewCPUSpec) ||
9990 (NewCPUDisp && NewCPUSpec)) {
9991 S.Diag(NewFD->getLocation(), diag::err_multiversion_types_mixed);
9992 NewFD->setInvalidDecl();
9996 MultiVersionKind MVType = NewFD->getMultiVersionKind();
9998 // Main isn't allowed to become a multiversion function, however it IS
9999 // permitted to have 'main' be marked with the 'target' optimization hint.
10000 if (NewFD->isMain()) {
10001 if ((MVType == MultiVersionKind::Target && NewTA->isDefaultVersion()) ||
10002 MVType == MultiVersionKind::CPUDispatch ||
10003 MVType == MultiVersionKind::CPUSpecific) {
10004 S.Diag(NewFD->getLocation(), diag::err_multiversion_not_allowed_on_main);
10005 NewFD->setInvalidDecl();
10011 if (!OldDecl || !OldDecl->getAsFunction() ||
10012 OldDecl->getDeclContext()->getRedeclContext() !=
10013 NewFD->getDeclContext()->getRedeclContext()) {
10014 // If there's no previous declaration, AND this isn't attempting to cause
10015 // multiversioning, this isn't an error condition.
10016 if (MVType == MultiVersionKind::None)
10018 return CheckMultiVersionFirstFunction(S, NewFD, MVType, NewTA);
10021 FunctionDecl *OldFD = OldDecl->getAsFunction();
10023 if (!OldFD->isMultiVersion() && MVType == MultiVersionKind::None)
10026 if (OldFD->isMultiVersion() && MVType == MultiVersionKind::None) {
10027 S.Diag(NewFD->getLocation(), diag::err_multiversion_required_in_redecl)
10028 << (OldFD->getMultiVersionKind() != MultiVersionKind::Target);
10029 NewFD->setInvalidDecl();
10033 // Handle the target potentially causes multiversioning case.
10034 if (!OldFD->isMultiVersion() && MVType == MultiVersionKind::Target)
10035 return CheckTargetCausesMultiVersioning(S, OldFD, NewFD, NewTA,
10036 Redeclaration, OldDecl,
10037 MergeTypeWithPrevious, Previous);
10039 // At this point, we have a multiversion function decl (in OldFD) AND an
10040 // appropriate attribute in the current function decl. Resolve that these are
10041 // still compatible with previous declarations.
10042 return CheckMultiVersionAdditionalDecl(
10043 S, OldFD, NewFD, MVType, NewTA, NewCPUDisp, NewCPUSpec, Redeclaration,
10044 OldDecl, MergeTypeWithPrevious, Previous);
10047 /// Perform semantic checking of a new function declaration.
10049 /// Performs semantic analysis of the new function declaration
10050 /// NewFD. This routine performs all semantic checking that does not
10051 /// require the actual declarator involved in the declaration, and is
10052 /// used both for the declaration of functions as they are parsed
10053 /// (called via ActOnDeclarator) and for the declaration of functions
10054 /// that have been instantiated via C++ template instantiation (called
10055 /// via InstantiateDecl).
10057 /// \param IsMemberSpecialization whether this new function declaration is
10058 /// a member specialization (that replaces any definition provided by the
10059 /// previous declaration).
10061 /// This sets NewFD->isInvalidDecl() to true if there was an error.
10063 /// \returns true if the function declaration is a redeclaration.
10064 bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
10065 LookupResult &Previous,
10066 bool IsMemberSpecialization) {
10067 assert(!NewFD->getReturnType()->isVariablyModifiedType() &&
10068 "Variably modified return types are not handled here");
10070 // Determine whether the type of this function should be merged with
10071 // a previous visible declaration. This never happens for functions in C++,
10072 // and always happens in C if the previous declaration was visible.
10073 bool MergeTypeWithPrevious = !getLangOpts().CPlusPlus &&
10074 !Previous.isShadowed();
10076 bool Redeclaration = false;
10077 NamedDecl *OldDecl = nullptr;
10078 bool MayNeedOverloadableChecks = false;
10080 // Merge or overload the declaration with an existing declaration of
10081 // the same name, if appropriate.
10082 if (!Previous.empty()) {
10083 // Determine whether NewFD is an overload of PrevDecl or
10084 // a declaration that requires merging. If it's an overload,
10085 // there's no more work to do here; we'll just add the new
10086 // function to the scope.
10087 if (!AllowOverloadingOfFunction(Previous, Context, NewFD)) {
10088 NamedDecl *Candidate = Previous.getRepresentativeDecl();
10089 if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) {
10090 Redeclaration = true;
10091 OldDecl = Candidate;
10094 MayNeedOverloadableChecks = true;
10095 switch (CheckOverload(S, NewFD, Previous, OldDecl,
10096 /*NewIsUsingDecl*/ false)) {
10098 Redeclaration = true;
10101 case Ovl_NonFunction:
10102 Redeclaration = true;
10106 Redeclaration = false;
10112 // Check for a previous extern "C" declaration with this name.
10113 if (!Redeclaration &&
10114 checkForConflictWithNonVisibleExternC(*this, NewFD, Previous)) {
10115 if (!Previous.empty()) {
10116 // This is an extern "C" declaration with the same name as a previous
10117 // declaration, and thus redeclares that entity...
10118 Redeclaration = true;
10119 OldDecl = Previous.getFoundDecl();
10120 MergeTypeWithPrevious = false;
10122 // ... except in the presence of __attribute__((overloadable)).
10123 if (OldDecl->hasAttr<OverloadableAttr>() ||
10124 NewFD->hasAttr<OverloadableAttr>()) {
10125 if (IsOverload(NewFD, cast<FunctionDecl>(OldDecl), false)) {
10126 MayNeedOverloadableChecks = true;
10127 Redeclaration = false;
10134 if (CheckMultiVersionFunction(*this, NewFD, Redeclaration, OldDecl,
10135 MergeTypeWithPrevious, Previous))
10136 return Redeclaration;
10138 // C++11 [dcl.constexpr]p8:
10139 // A constexpr specifier for a non-static member function that is not
10140 // a constructor declares that member function to be const.
10142 // This needs to be delayed until we know whether this is an out-of-line
10143 // definition of a static member function.
10145 // This rule is not present in C++1y, so we produce a backwards
10146 // compatibility warning whenever it happens in C++11.
10147 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
10148 if (!getLangOpts().CPlusPlus14 && MD && MD->isConstexpr() &&
10149 !MD->isStatic() && !isa<CXXConstructorDecl>(MD) &&
10150 !MD->getMethodQualifiers().hasConst()) {
10151 CXXMethodDecl *OldMD = nullptr;
10153 OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl->getAsFunction());
10154 if (!OldMD || !OldMD->isStatic()) {
10155 const FunctionProtoType *FPT =
10156 MD->getType()->castAs<FunctionProtoType>();
10157 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
10158 EPI.TypeQuals.addConst();
10159 MD->setType(Context.getFunctionType(FPT->getReturnType(),
10160 FPT->getParamTypes(), EPI));
10162 // Warn that we did this, if we're not performing template instantiation.
10163 // In that case, we'll have warned already when the template was defined.
10164 if (!inTemplateInstantiation()) {
10165 SourceLocation AddConstLoc;
10166 if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
10167 .IgnoreParens().getAs<FunctionTypeLoc>())
10168 AddConstLoc = getLocForEndOfToken(FTL.getRParenLoc());
10170 Diag(MD->getLocation(), diag::warn_cxx14_compat_constexpr_not_const)
10171 << FixItHint::CreateInsertion(AddConstLoc, " const");
10176 if (Redeclaration) {
10177 // NewFD and OldDecl represent declarations that need to be
10179 if (MergeFunctionDecl(NewFD, OldDecl, S, MergeTypeWithPrevious)) {
10180 NewFD->setInvalidDecl();
10181 return Redeclaration;
10185 Previous.addDecl(OldDecl);
10187 if (FunctionTemplateDecl *OldTemplateDecl =
10188 dyn_cast<FunctionTemplateDecl>(OldDecl)) {
10189 auto *OldFD = OldTemplateDecl->getTemplatedDecl();
10190 FunctionTemplateDecl *NewTemplateDecl
10191 = NewFD->getDescribedFunctionTemplate();
10192 assert(NewTemplateDecl && "Template/non-template mismatch");
10194 // The call to MergeFunctionDecl above may have created some state in
10195 // NewTemplateDecl that needs to be merged with OldTemplateDecl before we
10196 // can add it as a redeclaration.
10197 NewTemplateDecl->mergePrevDecl(OldTemplateDecl);
10199 NewFD->setPreviousDeclaration(OldFD);
10200 adjustDeclContextForDeclaratorDecl(NewFD, OldFD);
10201 if (NewFD->isCXXClassMember()) {
10202 NewFD->setAccess(OldTemplateDecl->getAccess());
10203 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess());
10206 // If this is an explicit specialization of a member that is a function
10207 // template, mark it as a member specialization.
10208 if (IsMemberSpecialization &&
10209 NewTemplateDecl->getInstantiatedFromMemberTemplate()) {
10210 NewTemplateDecl->setMemberSpecialization();
10211 assert(OldTemplateDecl->isMemberSpecialization());
10212 // Explicit specializations of a member template do not inherit deleted
10213 // status from the parent member template that they are specializing.
10214 if (OldFD->isDeleted()) {
10215 // FIXME: This assert will not hold in the presence of modules.
10216 assert(OldFD->getCanonicalDecl() == OldFD);
10217 // FIXME: We need an update record for this AST mutation.
10218 OldFD->setDeletedAsWritten(false);
10223 if (shouldLinkDependentDeclWithPrevious(NewFD, OldDecl)) {
10224 auto *OldFD = cast<FunctionDecl>(OldDecl);
10225 // This needs to happen first so that 'inline' propagates.
10226 NewFD->setPreviousDeclaration(OldFD);
10227 adjustDeclContextForDeclaratorDecl(NewFD, OldFD);
10228 if (NewFD->isCXXClassMember())
10229 NewFD->setAccess(OldFD->getAccess());
10232 } else if (!getLangOpts().CPlusPlus && MayNeedOverloadableChecks &&
10233 !NewFD->getAttr<OverloadableAttr>()) {
10234 assert((Previous.empty() ||
10235 llvm::any_of(Previous,
10236 [](const NamedDecl *ND) {
10237 return ND->hasAttr<OverloadableAttr>();
10239 "Non-redecls shouldn't happen without overloadable present");
10241 auto OtherUnmarkedIter = llvm::find_if(Previous, [](const NamedDecl *ND) {
10242 const auto *FD = dyn_cast<FunctionDecl>(ND);
10243 return FD && !FD->hasAttr<OverloadableAttr>();
10246 if (OtherUnmarkedIter != Previous.end()) {
10247 Diag(NewFD->getLocation(),
10248 diag::err_attribute_overloadable_multiple_unmarked_overloads);
10249 Diag((*OtherUnmarkedIter)->getLocation(),
10250 diag::note_attribute_overloadable_prev_overload)
10253 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
10257 // Semantic checking for this function declaration (in isolation).
10259 if (getLangOpts().CPlusPlus) {
10260 // C++-specific checks.
10261 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) {
10262 CheckConstructor(Constructor);
10263 } else if (CXXDestructorDecl *Destructor =
10264 dyn_cast<CXXDestructorDecl>(NewFD)) {
10265 CXXRecordDecl *Record = Destructor->getParent();
10266 QualType ClassType = Context.getTypeDeclType(Record);
10268 // FIXME: Shouldn't we be able to perform this check even when the class
10269 // type is dependent? Both gcc and edg can handle that.
10270 if (!ClassType->isDependentType()) {
10271 DeclarationName Name
10272 = Context.DeclarationNames.getCXXDestructorName(
10273 Context.getCanonicalType(ClassType));
10274 if (NewFD->getDeclName() != Name) {
10275 Diag(NewFD->getLocation(), diag::err_destructor_name);
10276 NewFD->setInvalidDecl();
10277 return Redeclaration;
10280 } else if (CXXConversionDecl *Conversion
10281 = dyn_cast<CXXConversionDecl>(NewFD)) {
10282 ActOnConversionDeclarator(Conversion);
10283 } else if (auto *Guide = dyn_cast<CXXDeductionGuideDecl>(NewFD)) {
10284 if (auto *TD = Guide->getDescribedFunctionTemplate())
10285 CheckDeductionGuideTemplate(TD);
10287 // A deduction guide is not on the list of entities that can be
10288 // explicitly specialized.
10289 if (Guide->getTemplateSpecializationKind() == TSK_ExplicitSpecialization)
10290 Diag(Guide->getBeginLoc(), diag::err_deduction_guide_specialized)
10291 << /*explicit specialization*/ 1;
10294 // Find any virtual functions that this function overrides.
10295 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) {
10296 if (!Method->isFunctionTemplateSpecialization() &&
10297 !Method->getDescribedFunctionTemplate() &&
10298 Method->isCanonicalDecl()) {
10299 if (AddOverriddenMethods(Method->getParent(), Method)) {
10300 // If the function was marked as "static", we have a problem.
10301 if (NewFD->getStorageClass() == SC_Static) {
10302 ReportOverrides(*this, diag::err_static_overrides_virtual, Method);
10307 if (Method->isStatic())
10308 checkThisInStaticMemberFunctionType(Method);
10311 // Extra checking for C++ overloaded operators (C++ [over.oper]).
10312 if (NewFD->isOverloadedOperator() &&
10313 CheckOverloadedOperatorDeclaration(NewFD)) {
10314 NewFD->setInvalidDecl();
10315 return Redeclaration;
10318 // Extra checking for C++0x literal operators (C++0x [over.literal]).
10319 if (NewFD->getLiteralIdentifier() &&
10320 CheckLiteralOperatorDeclaration(NewFD)) {
10321 NewFD->setInvalidDecl();
10322 return Redeclaration;
10325 // In C++, check default arguments now that we have merged decls. Unless
10326 // the lexical context is the class, because in this case this is done
10327 // during delayed parsing anyway.
10328 if (!CurContext->isRecord())
10329 CheckCXXDefaultArguments(NewFD);
10331 // If this function declares a builtin function, check the type of this
10332 // declaration against the expected type for the builtin.
10333 if (unsigned BuiltinID = NewFD->getBuiltinID()) {
10334 ASTContext::GetBuiltinTypeError Error;
10335 LookupPredefedObjCSuperType(*this, S, NewFD->getIdentifier());
10336 QualType T = Context.GetBuiltinType(BuiltinID, Error);
10337 // If the type of the builtin differs only in its exception
10338 // specification, that's OK.
10339 // FIXME: If the types do differ in this way, it would be better to
10340 // retain the 'noexcept' form of the type.
10342 !Context.hasSameFunctionTypeIgnoringExceptionSpec(T,
10344 // The type of this function differs from the type of the builtin,
10345 // so forget about the builtin entirely.
10346 Context.BuiltinInfo.forgetBuiltin(BuiltinID, Context.Idents);
10349 // If this function is declared as being extern "C", then check to see if
10350 // the function returns a UDT (class, struct, or union type) that is not C
10351 // compatible, and if it does, warn the user.
10352 // But, issue any diagnostic on the first declaration only.
10353 if (Previous.empty() && NewFD->isExternC()) {
10354 QualType R = NewFD->getReturnType();
10355 if (R->isIncompleteType() && !R->isVoidType())
10356 Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete)
10358 else if (!R.isPODType(Context) && !R->isVoidType() &&
10359 !R->isObjCObjectPointerType())
10360 Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R;
10363 // C++1z [dcl.fct]p6:
10364 // [...] whether the function has a non-throwing exception-specification
10365 // [is] part of the function type
10367 // This results in an ABI break between C++14 and C++17 for functions whose
10368 // declared type includes an exception-specification in a parameter or
10369 // return type. (Exception specifications on the function itself are OK in
10370 // most cases, and exception specifications are not permitted in most other
10371 // contexts where they could make it into a mangling.)
10372 if (!getLangOpts().CPlusPlus17 && !NewFD->getPrimaryTemplate()) {
10373 auto HasNoexcept = [&](QualType T) -> bool {
10374 // Strip off declarator chunks that could be between us and a function
10375 // type. We don't need to look far, exception specifications are very
10376 // restricted prior to C++17.
10377 if (auto *RT = T->getAs<ReferenceType>())
10378 T = RT->getPointeeType();
10379 else if (T->isAnyPointerType())
10380 T = T->getPointeeType();
10381 else if (auto *MPT = T->getAs<MemberPointerType>())
10382 T = MPT->getPointeeType();
10383 if (auto *FPT = T->getAs<FunctionProtoType>())
10384 if (FPT->isNothrow())
10389 auto *FPT = NewFD->getType()->castAs<FunctionProtoType>();
10390 bool AnyNoexcept = HasNoexcept(FPT->getReturnType());
10391 for (QualType T : FPT->param_types())
10392 AnyNoexcept |= HasNoexcept(T);
10394 Diag(NewFD->getLocation(),
10395 diag::warn_cxx17_compat_exception_spec_in_signature)
10399 if (!Redeclaration && LangOpts.CUDA)
10400 checkCUDATargetOverload(NewFD, Previous);
10402 return Redeclaration;
10405 void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) {
10406 // C++11 [basic.start.main]p3:
10407 // A program that [...] declares main to be inline, static or
10408 // constexpr is ill-formed.
10409 // C11 6.7.4p4: In a hosted environment, no function specifier(s) shall
10410 // appear in a declaration of main.
10411 // static main is not an error under C99, but we should warn about it.
10412 // We accept _Noreturn main as an extension.
10413 if (FD->getStorageClass() == SC_Static)
10414 Diag(DS.getStorageClassSpecLoc(), getLangOpts().CPlusPlus
10415 ? diag::err_static_main : diag::warn_static_main)
10416 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
10417 if (FD->isInlineSpecified())
10418 Diag(DS.getInlineSpecLoc(), diag::err_inline_main)
10419 << FixItHint::CreateRemoval(DS.getInlineSpecLoc());
10420 if (DS.isNoreturnSpecified()) {
10421 SourceLocation NoreturnLoc = DS.getNoreturnSpecLoc();
10422 SourceRange NoreturnRange(NoreturnLoc, getLocForEndOfToken(NoreturnLoc));
10423 Diag(NoreturnLoc, diag::ext_noreturn_main);
10424 Diag(NoreturnLoc, diag::note_main_remove_noreturn)
10425 << FixItHint::CreateRemoval(NoreturnRange);
10427 if (FD->isConstexpr()) {
10428 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_main)
10429 << FD->isConsteval()
10430 << FixItHint::CreateRemoval(DS.getConstexprSpecLoc());
10431 FD->setConstexprKind(CSK_unspecified);
10434 if (getLangOpts().OpenCL) {
10435 Diag(FD->getLocation(), diag::err_opencl_no_main)
10436 << FD->hasAttr<OpenCLKernelAttr>();
10437 FD->setInvalidDecl();
10441 QualType T = FD->getType();
10442 assert(T->isFunctionType() && "function decl is not of function type");
10443 const FunctionType* FT = T->castAs<FunctionType>();
10445 // Set default calling convention for main()
10446 if (FT->getCallConv() != CC_C) {
10447 FT = Context.adjustFunctionType(FT, FT->getExtInfo().withCallingConv(CC_C));
10448 FD->setType(QualType(FT, 0));
10449 T = Context.getCanonicalType(FD->getType());
10452 if (getLangOpts().GNUMode && !getLangOpts().CPlusPlus) {
10453 // In C with GNU extensions we allow main() to have non-integer return
10454 // type, but we should warn about the extension, and we disable the
10455 // implicit-return-zero rule.
10457 // GCC in C mode accepts qualified 'int'.
10458 if (Context.hasSameUnqualifiedType(FT->getReturnType(), Context.IntTy))
10459 FD->setHasImplicitReturnZero(true);
10461 Diag(FD->getTypeSpecStartLoc(), diag::ext_main_returns_nonint);
10462 SourceRange RTRange = FD->getReturnTypeSourceRange();
10463 if (RTRange.isValid())
10464 Diag(RTRange.getBegin(), diag::note_main_change_return_type)
10465 << FixItHint::CreateReplacement(RTRange, "int");
10468 // In C and C++, main magically returns 0 if you fall off the end;
10469 // set the flag which tells us that.
10470 // This is C++ [basic.start.main]p5 and C99 5.1.2.2.3.
10472 // All the standards say that main() should return 'int'.
10473 if (Context.hasSameType(FT->getReturnType(), Context.IntTy))
10474 FD->setHasImplicitReturnZero(true);
10476 // Otherwise, this is just a flat-out error.
10477 SourceRange RTRange = FD->getReturnTypeSourceRange();
10478 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint)
10479 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "int")
10481 FD->setInvalidDecl(true);
10485 // Treat protoless main() as nullary.
10486 if (isa<FunctionNoProtoType>(FT)) return;
10488 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT);
10489 unsigned nparams = FTP->getNumParams();
10490 assert(FD->getNumParams() == nparams);
10492 bool HasExtraParameters = (nparams > 3);
10494 if (FTP->isVariadic()) {
10495 Diag(FD->getLocation(), diag::ext_variadic_main);
10496 // FIXME: if we had information about the location of the ellipsis, we
10497 // could add a FixIt hint to remove it as a parameter.
10500 // Darwin passes an undocumented fourth argument of type char**. If
10501 // other platforms start sprouting these, the logic below will start
10503 if (nparams == 4 && Context.getTargetInfo().getTriple().isOSDarwin())
10504 HasExtraParameters = false;
10506 if (HasExtraParameters) {
10507 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams;
10508 FD->setInvalidDecl(true);
10512 // FIXME: a lot of the following diagnostics would be improved
10513 // if we had some location information about types.
10516 Context.getPointerType(Context.getPointerType(Context.CharTy));
10517 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP };
10519 for (unsigned i = 0; i < nparams; ++i) {
10520 QualType AT = FTP->getParamType(i);
10522 bool mismatch = true;
10524 if (Context.hasSameUnqualifiedType(AT, Expected[i]))
10526 else if (Expected[i] == CharPP) {
10527 // As an extension, the following forms are okay:
10529 // char const * const *
10532 QualifierCollector qs;
10533 const PointerType* PT;
10534 if ((PT = qs.strip(AT)->getAs<PointerType>()) &&
10535 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) &&
10536 Context.hasSameType(QualType(qs.strip(PT->getPointeeType()), 0),
10539 mismatch = !qs.empty();
10544 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i];
10545 // TODO: suggest replacing given type with expected type
10546 FD->setInvalidDecl(true);
10550 if (nparams == 1 && !FD->isInvalidDecl()) {
10551 Diag(FD->getLocation(), diag::warn_main_one_arg);
10554 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
10555 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
10556 FD->setInvalidDecl();
10560 void Sema::CheckMSVCRTEntryPoint(FunctionDecl *FD) {
10561 QualType T = FD->getType();
10562 assert(T->isFunctionType() && "function decl is not of function type");
10563 const FunctionType *FT = T->castAs<FunctionType>();
10565 // Set an implicit return of 'zero' if the function can return some integral,
10566 // enumeration, pointer or nullptr type.
10567 if (FT->getReturnType()->isIntegralOrEnumerationType() ||
10568 FT->getReturnType()->isAnyPointerType() ||
10569 FT->getReturnType()->isNullPtrType())
10570 // DllMain is exempt because a return value of zero means it failed.
10571 if (FD->getName() != "DllMain")
10572 FD->setHasImplicitReturnZero(true);
10574 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
10575 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
10576 FD->setInvalidDecl();
10580 bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
10581 // FIXME: Need strict checking. In C89, we need to check for
10582 // any assignment, increment, decrement, function-calls, or
10583 // commas outside of a sizeof. In C99, it's the same list,
10584 // except that the aforementioned are allowed in unevaluated
10585 // expressions. Everything else falls under the
10586 // "may accept other forms of constant expressions" exception.
10587 // (We never end up here for C++, so the constant expression
10588 // rules there don't matter.)
10589 const Expr *Culprit;
10590 if (Init->isConstantInitializer(Context, false, &Culprit))
10592 Diag(Culprit->getExprLoc(), diag::err_init_element_not_constant)
10593 << Culprit->getSourceRange();
10598 // Visits an initialization expression to see if OrigDecl is evaluated in
10599 // its own initialization and throws a warning if it does.
10600 class SelfReferenceChecker
10601 : public EvaluatedExprVisitor<SelfReferenceChecker> {
10606 bool isReferenceType;
10609 llvm::SmallVector<unsigned, 4> InitFieldIndex;
10612 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited;
10614 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context),
10615 S(S), OrigDecl(OrigDecl) {
10617 isRecordType = false;
10618 isReferenceType = false;
10619 isInitList = false;
10620 if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) {
10621 isPODType = VD->getType().isPODType(S.Context);
10622 isRecordType = VD->getType()->isRecordType();
10623 isReferenceType = VD->getType()->isReferenceType();
10627 // For most expressions, just call the visitor. For initializer lists,
10628 // track the index of the field being initialized since fields are
10629 // initialized in order allowing use of previously initialized fields.
10630 void CheckExpr(Expr *E) {
10631 InitListExpr *InitList = dyn_cast<InitListExpr>(E);
10637 // Track and increment the index here.
10639 InitFieldIndex.push_back(0);
10640 for (auto Child : InitList->children()) {
10641 CheckExpr(cast<Expr>(Child));
10642 ++InitFieldIndex.back();
10644 InitFieldIndex.pop_back();
10647 // Returns true if MemberExpr is checked and no further checking is needed.
10648 // Returns false if additional checking is required.
10649 bool CheckInitListMemberExpr(MemberExpr *E, bool CheckReference) {
10650 llvm::SmallVector<FieldDecl*, 4> Fields;
10652 bool ReferenceField = false;
10654 // Get the field members used.
10655 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
10656 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
10659 Fields.push_back(FD);
10660 if (FD->getType()->isReferenceType())
10661 ReferenceField = true;
10662 Base = ME->getBase()->IgnoreParenImpCasts();
10665 // Keep checking only if the base Decl is the same.
10666 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base);
10667 if (!DRE || DRE->getDecl() != OrigDecl)
10670 // A reference field can be bound to an unininitialized field.
10671 if (CheckReference && !ReferenceField)
10674 // Convert FieldDecls to their index number.
10675 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
10676 for (const FieldDecl *I : llvm::reverse(Fields))
10677 UsedFieldIndex.push_back(I->getFieldIndex());
10679 // See if a warning is needed by checking the first difference in index
10680 // numbers. If field being used has index less than the field being
10681 // initialized, then the use is safe.
10682 for (auto UsedIter = UsedFieldIndex.begin(),
10683 UsedEnd = UsedFieldIndex.end(),
10684 OrigIter = InitFieldIndex.begin(),
10685 OrigEnd = InitFieldIndex.end();
10686 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
10687 if (*UsedIter < *OrigIter)
10689 if (*UsedIter > *OrigIter)
10693 // TODO: Add a different warning which will print the field names.
10694 HandleDeclRefExpr(DRE);
10698 // For most expressions, the cast is directly above the DeclRefExpr.
10699 // For conditional operators, the cast can be outside the conditional
10700 // operator if both expressions are DeclRefExpr's.
10701 void HandleValue(Expr *E) {
10702 E = E->IgnoreParens();
10703 if (DeclRefExpr* DRE = dyn_cast<DeclRefExpr>(E)) {
10704 HandleDeclRefExpr(DRE);
10708 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
10709 Visit(CO->getCond());
10710 HandleValue(CO->getTrueExpr());
10711 HandleValue(CO->getFalseExpr());
10715 if (BinaryConditionalOperator *BCO =
10716 dyn_cast<BinaryConditionalOperator>(E)) {
10717 Visit(BCO->getCond());
10718 HandleValue(BCO->getFalseExpr());
10722 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
10723 HandleValue(OVE->getSourceExpr());
10727 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
10728 if (BO->getOpcode() == BO_Comma) {
10729 Visit(BO->getLHS());
10730 HandleValue(BO->getRHS());
10735 if (isa<MemberExpr>(E)) {
10737 if (CheckInitListMemberExpr(cast<MemberExpr>(E),
10738 false /*CheckReference*/))
10742 Expr *Base = E->IgnoreParenImpCasts();
10743 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
10744 // Check for static member variables and don't warn on them.
10745 if (!isa<FieldDecl>(ME->getMemberDecl()))
10747 Base = ME->getBase()->IgnoreParenImpCasts();
10749 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base))
10750 HandleDeclRefExpr(DRE);
10757 // Reference types not handled in HandleValue are handled here since all
10758 // uses of references are bad, not just r-value uses.
10759 void VisitDeclRefExpr(DeclRefExpr *E) {
10760 if (isReferenceType)
10761 HandleDeclRefExpr(E);
10764 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
10765 if (E->getCastKind() == CK_LValueToRValue) {
10766 HandleValue(E->getSubExpr());
10770 Inherited::VisitImplicitCastExpr(E);
10773 void VisitMemberExpr(MemberExpr *E) {
10775 if (CheckInitListMemberExpr(E, true /*CheckReference*/))
10779 // Don't warn on arrays since they can be treated as pointers.
10780 if (E->getType()->canDecayToPointerType()) return;
10782 // Warn when a non-static method call is followed by non-static member
10783 // field accesses, which is followed by a DeclRefExpr.
10784 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl());
10785 bool Warn = (MD && !MD->isStatic());
10786 Expr *Base = E->getBase()->IgnoreParenImpCasts();
10787 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
10788 if (!isa<FieldDecl>(ME->getMemberDecl()))
10790 Base = ME->getBase()->IgnoreParenImpCasts();
10793 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
10795 HandleDeclRefExpr(DRE);
10799 // The base of a MemberExpr is not a MemberExpr or a DeclRefExpr.
10800 // Visit that expression.
10804 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
10805 Expr *Callee = E->getCallee();
10807 if (isa<UnresolvedLookupExpr>(Callee))
10808 return Inherited::VisitCXXOperatorCallExpr(E);
10811 for (auto Arg: E->arguments())
10812 HandleValue(Arg->IgnoreParenImpCasts());
10815 void VisitUnaryOperator(UnaryOperator *E) {
10816 // For POD record types, addresses of its own members are well-defined.
10817 if (E->getOpcode() == UO_AddrOf && isRecordType &&
10818 isa<MemberExpr>(E->getSubExpr()->IgnoreParens())) {
10820 HandleValue(E->getSubExpr());
10824 if (E->isIncrementDecrementOp()) {
10825 HandleValue(E->getSubExpr());
10829 Inherited::VisitUnaryOperator(E);
10832 void VisitObjCMessageExpr(ObjCMessageExpr *E) {}
10834 void VisitCXXConstructExpr(CXXConstructExpr *E) {
10835 if (E->getConstructor()->isCopyConstructor()) {
10836 Expr *ArgExpr = E->getArg(0);
10837 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
10838 if (ILE->getNumInits() == 1)
10839 ArgExpr = ILE->getInit(0);
10840 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
10841 if (ICE->getCastKind() == CK_NoOp)
10842 ArgExpr = ICE->getSubExpr();
10843 HandleValue(ArgExpr);
10846 Inherited::VisitCXXConstructExpr(E);
10849 void VisitCallExpr(CallExpr *E) {
10850 // Treat std::move as a use.
10851 if (E->isCallToStdMove()) {
10852 HandleValue(E->getArg(0));
10856 Inherited::VisitCallExpr(E);
10859 void VisitBinaryOperator(BinaryOperator *E) {
10860 if (E->isCompoundAssignmentOp()) {
10861 HandleValue(E->getLHS());
10862 Visit(E->getRHS());
10866 Inherited::VisitBinaryOperator(E);
10869 // A custom visitor for BinaryConditionalOperator is needed because the
10870 // regular visitor would check the condition and true expression separately
10871 // but both point to the same place giving duplicate diagnostics.
10872 void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
10873 Visit(E->getCond());
10874 Visit(E->getFalseExpr());
10877 void HandleDeclRefExpr(DeclRefExpr *DRE) {
10878 Decl* ReferenceDecl = DRE->getDecl();
10879 if (OrigDecl != ReferenceDecl) return;
10881 if (isReferenceType) {
10882 diag = diag::warn_uninit_self_reference_in_reference_init;
10883 } else if (cast<VarDecl>(OrigDecl)->isStaticLocal()) {
10884 diag = diag::warn_static_self_reference_in_init;
10885 } else if (isa<TranslationUnitDecl>(OrigDecl->getDeclContext()) ||
10886 isa<NamespaceDecl>(OrigDecl->getDeclContext()) ||
10887 DRE->getDecl()->getType()->isRecordType()) {
10888 diag = diag::warn_uninit_self_reference_in_init;
10890 // Local variables will be handled by the CFG analysis.
10894 S.DiagRuntimeBehavior(DRE->getBeginLoc(), DRE,
10896 << DRE->getDecl() << OrigDecl->getLocation()
10897 << DRE->getSourceRange());
10901 /// CheckSelfReference - Warns if OrigDecl is used in expression E.
10902 static void CheckSelfReference(Sema &S, Decl* OrigDecl, Expr *E,
10904 // Parameters arguments are occassionially constructed with itself,
10905 // for instance, in recursive functions. Skip them.
10906 if (isa<ParmVarDecl>(OrigDecl))
10909 E = E->IgnoreParens();
10911 // Skip checking T a = a where T is not a record or reference type.
10912 // Doing so is a way to silence uninitialized warnings.
10913 if (!DirectInit && !cast<VarDecl>(OrigDecl)->getType()->isRecordType())
10914 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
10915 if (ICE->getCastKind() == CK_LValueToRValue)
10916 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()))
10917 if (DRE->getDecl() == OrigDecl)
10920 SelfReferenceChecker(S, OrigDecl).CheckExpr(E);
10922 } // end anonymous namespace
10925 // Simple wrapper to add the name of a variable or (if no variable is
10926 // available) a DeclarationName into a diagnostic.
10927 struct VarDeclOrName {
10929 DeclarationName Name;
10931 friend const Sema::SemaDiagnosticBuilder &
10932 operator<<(const Sema::SemaDiagnosticBuilder &Diag, VarDeclOrName VN) {
10933 return VN.VDecl ? Diag << VN.VDecl : Diag << VN.Name;
10936 } // end anonymous namespace
10938 QualType Sema::deduceVarTypeFromInitializer(VarDecl *VDecl,
10939 DeclarationName Name, QualType Type,
10940 TypeSourceInfo *TSI,
10941 SourceRange Range, bool DirectInit,
10943 bool IsInitCapture = !VDecl;
10944 assert((!VDecl || !VDecl->isInitCapture()) &&
10945 "init captures are expected to be deduced prior to initialization");
10947 VarDeclOrName VN{VDecl, Name};
10949 DeducedType *Deduced = Type->getContainedDeducedType();
10950 assert(Deduced && "deduceVarTypeFromInitializer for non-deduced type");
10952 // C++11 [dcl.spec.auto]p3
10954 assert(VDecl && "no init for init capture deduction?");
10956 // Except for class argument deduction, and then for an initializing
10957 // declaration only, i.e. no static at class scope or extern.
10958 if (!isa<DeducedTemplateSpecializationType>(Deduced) ||
10959 VDecl->hasExternalStorage() ||
10960 VDecl->isStaticDataMember()) {
10961 Diag(VDecl->getLocation(), diag::err_auto_var_requires_init)
10962 << VDecl->getDeclName() << Type;
10967 ArrayRef<Expr*> DeduceInits;
10969 DeduceInits = Init;
10972 if (auto *PL = dyn_cast_or_null<ParenListExpr>(Init))
10973 DeduceInits = PL->exprs();
10976 if (isa<DeducedTemplateSpecializationType>(Deduced)) {
10977 assert(VDecl && "non-auto type for init capture deduction?");
10978 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
10979 InitializationKind Kind = InitializationKind::CreateForInit(
10980 VDecl->getLocation(), DirectInit, Init);
10981 // FIXME: Initialization should not be taking a mutable list of inits.
10982 SmallVector<Expr*, 8> InitsCopy(DeduceInits.begin(), DeduceInits.end());
10983 return DeduceTemplateSpecializationFromInitializer(TSI, Entity, Kind,
10988 if (auto *IL = dyn_cast<InitListExpr>(Init))
10989 DeduceInits = IL->inits();
10992 // Deduction only works if we have exactly one source expression.
10993 if (DeduceInits.empty()) {
10994 // It isn't possible to write this directly, but it is possible to
10995 // end up in this situation with "auto x(some_pack...);"
10996 Diag(Init->getBeginLoc(), IsInitCapture
10997 ? diag::err_init_capture_no_expression
10998 : diag::err_auto_var_init_no_expression)
10999 << VN << Type << Range;
11003 if (DeduceInits.size() > 1) {
11004 Diag(DeduceInits[1]->getBeginLoc(),
11005 IsInitCapture ? diag::err_init_capture_multiple_expressions
11006 : diag::err_auto_var_init_multiple_expressions)
11007 << VN << Type << Range;
11011 Expr *DeduceInit = DeduceInits[0];
11012 if (DirectInit && isa<InitListExpr>(DeduceInit)) {
11013 Diag(Init->getBeginLoc(), IsInitCapture
11014 ? diag::err_init_capture_paren_braces
11015 : diag::err_auto_var_init_paren_braces)
11016 << isa<InitListExpr>(Init) << VN << Type << Range;
11020 // Expressions default to 'id' when we're in a debugger.
11021 bool DefaultedAnyToId = false;
11022 if (getLangOpts().DebuggerCastResultToId &&
11023 Init->getType() == Context.UnknownAnyTy && !IsInitCapture) {
11024 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
11025 if (Result.isInvalid()) {
11028 Init = Result.get();
11029 DefaultedAnyToId = true;
11032 // C++ [dcl.decomp]p1:
11033 // If the assignment-expression [...] has array type A and no ref-qualifier
11034 // is present, e has type cv A
11035 if (VDecl && isa<DecompositionDecl>(VDecl) &&
11036 Context.hasSameUnqualifiedType(Type, Context.getAutoDeductType()) &&
11037 DeduceInit->getType()->isConstantArrayType())
11038 return Context.getQualifiedType(DeduceInit->getType(),
11039 Type.getQualifiers());
11041 QualType DeducedType;
11042 if (DeduceAutoType(TSI, DeduceInit, DeducedType) == DAR_Failed) {
11043 if (!IsInitCapture)
11044 DiagnoseAutoDeductionFailure(VDecl, DeduceInit);
11045 else if (isa<InitListExpr>(Init))
11046 Diag(Range.getBegin(),
11047 diag::err_init_capture_deduction_failure_from_init_list)
11049 << (DeduceInit->getType().isNull() ? TSI->getType()
11050 : DeduceInit->getType())
11051 << DeduceInit->getSourceRange();
11053 Diag(Range.getBegin(), diag::err_init_capture_deduction_failure)
11054 << VN << TSI->getType()
11055 << (DeduceInit->getType().isNull() ? TSI->getType()
11056 : DeduceInit->getType())
11057 << DeduceInit->getSourceRange();
11060 // Warn if we deduced 'id'. 'auto' usually implies type-safety, but using
11061 // 'id' instead of a specific object type prevents most of our usual
11063 // We only want to warn outside of template instantiations, though:
11064 // inside a template, the 'id' could have come from a parameter.
11065 if (!inTemplateInstantiation() && !DefaultedAnyToId && !IsInitCapture &&
11066 !DeducedType.isNull() && DeducedType->isObjCIdType()) {
11067 SourceLocation Loc = TSI->getTypeLoc().getBeginLoc();
11068 Diag(Loc, diag::warn_auto_var_is_id) << VN << Range;
11071 return DeducedType;
11074 bool Sema::DeduceVariableDeclarationType(VarDecl *VDecl, bool DirectInit,
11076 QualType DeducedType = deduceVarTypeFromInitializer(
11077 VDecl, VDecl->getDeclName(), VDecl->getType(), VDecl->getTypeSourceInfo(),
11078 VDecl->getSourceRange(), DirectInit, Init);
11079 if (DeducedType.isNull()) {
11080 VDecl->setInvalidDecl();
11084 VDecl->setType(DeducedType);
11085 assert(VDecl->isLinkageValid());
11087 // In ARC, infer lifetime.
11088 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(VDecl))
11089 VDecl->setInvalidDecl();
11091 // If this is a redeclaration, check that the type we just deduced matches
11092 // the previously declared type.
11093 if (VarDecl *Old = VDecl->getPreviousDecl()) {
11094 // We never need to merge the type, because we cannot form an incomplete
11095 // array of auto, nor deduce such a type.
11096 MergeVarDeclTypes(VDecl, Old, /*MergeTypeWithPrevious*/ false);
11099 // Check the deduced type is valid for a variable declaration.
11100 CheckVariableDeclarationType(VDecl);
11101 return VDecl->isInvalidDecl();
11104 void Sema::checkNonTrivialCUnionInInitializer(const Expr *Init,
11105 SourceLocation Loc) {
11106 if (auto *CE = dyn_cast<ConstantExpr>(Init))
11107 Init = CE->getSubExpr();
11109 QualType InitType = Init->getType();
11110 assert((InitType.hasNonTrivialToPrimitiveDefaultInitializeCUnion() ||
11111 InitType.hasNonTrivialToPrimitiveCopyCUnion()) &&
11112 "shouldn't be called if type doesn't have a non-trivial C struct");
11113 if (auto *ILE = dyn_cast<InitListExpr>(Init)) {
11114 for (auto I : ILE->inits()) {
11115 if (!I->getType().hasNonTrivialToPrimitiveDefaultInitializeCUnion() &&
11116 !I->getType().hasNonTrivialToPrimitiveCopyCUnion())
11118 SourceLocation SL = I->getExprLoc();
11119 checkNonTrivialCUnionInInitializer(I, SL.isValid() ? SL : Loc);
11124 if (isa<ImplicitValueInitExpr>(Init)) {
11125 if (InitType.hasNonTrivialToPrimitiveDefaultInitializeCUnion())
11126 checkNonTrivialCUnion(InitType, Loc, NTCUC_DefaultInitializedObject,
11129 // Assume all other explicit initializers involving copying some existing
11131 // TODO: ignore any explicit initializers where we can guarantee
11133 if (InitType.hasNonTrivialToPrimitiveCopyCUnion())
11134 checkNonTrivialCUnion(InitType, Loc, NTCUC_CopyInit, NTCUK_Copy);
11140 struct DiagNonTrivalCUnionDefaultInitializeVisitor
11141 : DefaultInitializedTypeVisitor<DiagNonTrivalCUnionDefaultInitializeVisitor,
11144 DefaultInitializedTypeVisitor<DiagNonTrivalCUnionDefaultInitializeVisitor,
11147 DiagNonTrivalCUnionDefaultInitializeVisitor(
11148 QualType OrigTy, SourceLocation OrigLoc,
11149 Sema::NonTrivialCUnionContext UseContext, Sema &S)
11150 : OrigTy(OrigTy), OrigLoc(OrigLoc), UseContext(UseContext), S(S) {}
11152 void visitWithKind(QualType::PrimitiveDefaultInitializeKind PDIK, QualType QT,
11153 const FieldDecl *FD, bool InNonTrivialUnion) {
11154 if (const auto *AT = S.Context.getAsArrayType(QT))
11155 return this->asDerived().visit(S.Context.getBaseElementType(AT), FD,
11156 InNonTrivialUnion);
11157 return Super::visitWithKind(PDIK, QT, FD, InNonTrivialUnion);
11160 void visitARCStrong(QualType QT, const FieldDecl *FD,
11161 bool InNonTrivialUnion) {
11162 if (InNonTrivialUnion)
11163 S.Diag(FD->getLocation(), diag::note_non_trivial_c_union)
11164 << 1 << 0 << QT << FD->getName();
11167 void visitARCWeak(QualType QT, const FieldDecl *FD, bool InNonTrivialUnion) {
11168 if (InNonTrivialUnion)
11169 S.Diag(FD->getLocation(), diag::note_non_trivial_c_union)
11170 << 1 << 0 << QT << FD->getName();
11173 void visitStruct(QualType QT, const FieldDecl *FD, bool InNonTrivialUnion) {
11174 const RecordDecl *RD = QT->castAs<RecordType>()->getDecl();
11175 if (RD->isUnion()) {
11176 if (OrigLoc.isValid()) {
11177 bool IsUnion = false;
11178 if (auto *OrigRD = OrigTy->getAsRecordDecl())
11179 IsUnion = OrigRD->isUnion();
11180 S.Diag(OrigLoc, diag::err_non_trivial_c_union_in_invalid_context)
11181 << 0 << OrigTy << IsUnion << UseContext;
11182 // Reset OrigLoc so that this diagnostic is emitted only once.
11183 OrigLoc = SourceLocation();
11185 InNonTrivialUnion = true;
11188 if (InNonTrivialUnion)
11189 S.Diag(RD->getLocation(), diag::note_non_trivial_c_union)
11190 << 0 << 0 << QT.getUnqualifiedType() << "";
11192 for (const FieldDecl *FD : RD->fields())
11193 asDerived().visit(FD->getType(), FD, InNonTrivialUnion);
11196 void visitTrivial(QualType QT, const FieldDecl *FD, bool InNonTrivialUnion) {}
11198 // The non-trivial C union type or the struct/union type that contains a
11199 // non-trivial C union.
11201 SourceLocation OrigLoc;
11202 Sema::NonTrivialCUnionContext UseContext;
11206 struct DiagNonTrivalCUnionDestructedTypeVisitor
11207 : DestructedTypeVisitor<DiagNonTrivalCUnionDestructedTypeVisitor, void> {
11209 DestructedTypeVisitor<DiagNonTrivalCUnionDestructedTypeVisitor, void>;
11211 DiagNonTrivalCUnionDestructedTypeVisitor(
11212 QualType OrigTy, SourceLocation OrigLoc,
11213 Sema::NonTrivialCUnionContext UseContext, Sema &S)
11214 : OrigTy(OrigTy), OrigLoc(OrigLoc), UseContext(UseContext), S(S) {}
11216 void visitWithKind(QualType::DestructionKind DK, QualType QT,
11217 const FieldDecl *FD, bool InNonTrivialUnion) {
11218 if (const auto *AT = S.Context.getAsArrayType(QT))
11219 return this->asDerived().visit(S.Context.getBaseElementType(AT), FD,
11220 InNonTrivialUnion);
11221 return Super::visitWithKind(DK, QT, FD, InNonTrivialUnion);
11224 void visitARCStrong(QualType QT, const FieldDecl *FD,
11225 bool InNonTrivialUnion) {
11226 if (InNonTrivialUnion)
11227 S.Diag(FD->getLocation(), diag::note_non_trivial_c_union)
11228 << 1 << 1 << QT << FD->getName();
11231 void visitARCWeak(QualType QT, const FieldDecl *FD, bool InNonTrivialUnion) {
11232 if (InNonTrivialUnion)
11233 S.Diag(FD->getLocation(), diag::note_non_trivial_c_union)
11234 << 1 << 1 << QT << FD->getName();
11237 void visitStruct(QualType QT, const FieldDecl *FD, bool InNonTrivialUnion) {
11238 const RecordDecl *RD = QT->castAs<RecordType>()->getDecl();
11239 if (RD->isUnion()) {
11240 if (OrigLoc.isValid()) {
11241 bool IsUnion = false;
11242 if (auto *OrigRD = OrigTy->getAsRecordDecl())
11243 IsUnion = OrigRD->isUnion();
11244 S.Diag(OrigLoc, diag::err_non_trivial_c_union_in_invalid_context)
11245 << 1 << OrigTy << IsUnion << UseContext;
11246 // Reset OrigLoc so that this diagnostic is emitted only once.
11247 OrigLoc = SourceLocation();
11249 InNonTrivialUnion = true;
11252 if (InNonTrivialUnion)
11253 S.Diag(RD->getLocation(), diag::note_non_trivial_c_union)
11254 << 0 << 1 << QT.getUnqualifiedType() << "";
11256 for (const FieldDecl *FD : RD->fields())
11257 asDerived().visit(FD->getType(), FD, InNonTrivialUnion);
11260 void visitTrivial(QualType QT, const FieldDecl *FD, bool InNonTrivialUnion) {}
11261 void visitCXXDestructor(QualType QT, const FieldDecl *FD,
11262 bool InNonTrivialUnion) {}
11264 // The non-trivial C union type or the struct/union type that contains a
11265 // non-trivial C union.
11267 SourceLocation OrigLoc;
11268 Sema::NonTrivialCUnionContext UseContext;
11272 struct DiagNonTrivalCUnionCopyVisitor
11273 : CopiedTypeVisitor<DiagNonTrivalCUnionCopyVisitor, false, void> {
11274 using Super = CopiedTypeVisitor<DiagNonTrivalCUnionCopyVisitor, false, void>;
11276 DiagNonTrivalCUnionCopyVisitor(QualType OrigTy, SourceLocation OrigLoc,
11277 Sema::NonTrivialCUnionContext UseContext,
11279 : OrigTy(OrigTy), OrigLoc(OrigLoc), UseContext(UseContext), S(S) {}
11281 void visitWithKind(QualType::PrimitiveCopyKind PCK, QualType QT,
11282 const FieldDecl *FD, bool InNonTrivialUnion) {
11283 if (const auto *AT = S.Context.getAsArrayType(QT))
11284 return this->asDerived().visit(S.Context.getBaseElementType(AT), FD,
11285 InNonTrivialUnion);
11286 return Super::visitWithKind(PCK, QT, FD, InNonTrivialUnion);
11289 void visitARCStrong(QualType QT, const FieldDecl *FD,
11290 bool InNonTrivialUnion) {
11291 if (InNonTrivialUnion)
11292 S.Diag(FD->getLocation(), diag::note_non_trivial_c_union)
11293 << 1 << 2 << QT << FD->getName();
11296 void visitARCWeak(QualType QT, const FieldDecl *FD, bool InNonTrivialUnion) {
11297 if (InNonTrivialUnion)
11298 S.Diag(FD->getLocation(), diag::note_non_trivial_c_union)
11299 << 1 << 2 << QT << FD->getName();
11302 void visitStruct(QualType QT, const FieldDecl *FD, bool InNonTrivialUnion) {
11303 const RecordDecl *RD = QT->castAs<RecordType>()->getDecl();
11304 if (RD->isUnion()) {
11305 if (OrigLoc.isValid()) {
11306 bool IsUnion = false;
11307 if (auto *OrigRD = OrigTy->getAsRecordDecl())
11308 IsUnion = OrigRD->isUnion();
11309 S.Diag(OrigLoc, diag::err_non_trivial_c_union_in_invalid_context)
11310 << 2 << OrigTy << IsUnion << UseContext;
11311 // Reset OrigLoc so that this diagnostic is emitted only once.
11312 OrigLoc = SourceLocation();
11314 InNonTrivialUnion = true;
11317 if (InNonTrivialUnion)
11318 S.Diag(RD->getLocation(), diag::note_non_trivial_c_union)
11319 << 0 << 2 << QT.getUnqualifiedType() << "";
11321 for (const FieldDecl *FD : RD->fields())
11322 asDerived().visit(FD->getType(), FD, InNonTrivialUnion);
11325 void preVisit(QualType::PrimitiveCopyKind PCK, QualType QT,
11326 const FieldDecl *FD, bool InNonTrivialUnion) {}
11327 void visitTrivial(QualType QT, const FieldDecl *FD, bool InNonTrivialUnion) {}
11328 void visitVolatileTrivial(QualType QT, const FieldDecl *FD,
11329 bool InNonTrivialUnion) {}
11331 // The non-trivial C union type or the struct/union type that contains a
11332 // non-trivial C union.
11334 SourceLocation OrigLoc;
11335 Sema::NonTrivialCUnionContext UseContext;
11341 void Sema::checkNonTrivialCUnion(QualType QT, SourceLocation Loc,
11342 NonTrivialCUnionContext UseContext,
11343 unsigned NonTrivialKind) {
11344 assert((QT.hasNonTrivialToPrimitiveDefaultInitializeCUnion() ||
11345 QT.hasNonTrivialToPrimitiveDestructCUnion() ||
11346 QT.hasNonTrivialToPrimitiveCopyCUnion()) &&
11347 "shouldn't be called if type doesn't have a non-trivial C union");
11349 if ((NonTrivialKind & NTCUK_Init) &&
11350 QT.hasNonTrivialToPrimitiveDefaultInitializeCUnion())
11351 DiagNonTrivalCUnionDefaultInitializeVisitor(QT, Loc, UseContext, *this)
11352 .visit(QT, nullptr, false);
11353 if ((NonTrivialKind & NTCUK_Destruct) &&
11354 QT.hasNonTrivialToPrimitiveDestructCUnion())
11355 DiagNonTrivalCUnionDestructedTypeVisitor(QT, Loc, UseContext, *this)
11356 .visit(QT, nullptr, false);
11357 if ((NonTrivialKind & NTCUK_Copy) && QT.hasNonTrivialToPrimitiveCopyCUnion())
11358 DiagNonTrivalCUnionCopyVisitor(QT, Loc, UseContext, *this)
11359 .visit(QT, nullptr, false);
11362 /// AddInitializerToDecl - Adds the initializer Init to the
11363 /// declaration dcl. If DirectInit is true, this is C++ direct
11364 /// initialization rather than copy initialization.
11365 void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) {
11366 // If there is no declaration, there was an error parsing it. Just ignore
11367 // the initializer.
11368 if (!RealDecl || RealDecl->isInvalidDecl()) {
11369 CorrectDelayedTyposInExpr(Init, dyn_cast_or_null<VarDecl>(RealDecl));
11373 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) {
11374 // Pure-specifiers are handled in ActOnPureSpecifier.
11375 Diag(Method->getLocation(), diag::err_member_function_initialization)
11376 << Method->getDeclName() << Init->getSourceRange();
11377 Method->setInvalidDecl();
11381 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl);
11383 assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here");
11384 Diag(RealDecl->getLocation(), diag::err_illegal_initializer);
11385 RealDecl->setInvalidDecl();
11389 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for.
11390 if (VDecl->getType()->isUndeducedType()) {
11391 // Attempt typo correction early so that the type of the init expression can
11392 // be deduced based on the chosen correction if the original init contains a
11394 ExprResult Res = CorrectDelayedTyposInExpr(Init, VDecl);
11395 if (!Res.isUsable()) {
11396 RealDecl->setInvalidDecl();
11401 if (DeduceVariableDeclarationType(VDecl, DirectInit, Init))
11405 // dllimport cannot be used on variable definitions.
11406 if (VDecl->hasAttr<DLLImportAttr>() && !VDecl->isStaticDataMember()) {
11407 Diag(VDecl->getLocation(), diag::err_attribute_dllimport_data_definition);
11408 VDecl->setInvalidDecl();
11412 if (VDecl->isLocalVarDecl() && VDecl->hasExternalStorage()) {
11413 // C99 6.7.8p5. C++ has no such restriction, but that is a defect.
11414 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init);
11415 VDecl->setInvalidDecl();
11419 if (!VDecl->getType()->isDependentType()) {
11420 // A definition must end up with a complete type, which means it must be
11421 // complete with the restriction that an array type might be completed by
11422 // the initializer; note that later code assumes this restriction.
11423 QualType BaseDeclType = VDecl->getType();
11424 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType))
11425 BaseDeclType = Array->getElementType();
11426 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType,
11427 diag::err_typecheck_decl_incomplete_type)) {
11428 RealDecl->setInvalidDecl();
11432 // The variable can not have an abstract class type.
11433 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(),
11434 diag::err_abstract_type_in_decl,
11435 AbstractVariableType))
11436 VDecl->setInvalidDecl();
11439 // If adding the initializer will turn this declaration into a definition,
11440 // and we already have a definition for this variable, diagnose or otherwise
11441 // handle the situation.
11443 if ((Def = VDecl->getDefinition()) && Def != VDecl &&
11444 (!VDecl->isStaticDataMember() || VDecl->isOutOfLine()) &&
11445 !VDecl->isThisDeclarationADemotedDefinition() &&
11446 checkVarDeclRedefinition(Def, VDecl))
11449 if (getLangOpts().CPlusPlus) {
11450 // C++ [class.static.data]p4
11451 // If a static data member is of const integral or const
11452 // enumeration type, its declaration in the class definition can
11453 // specify a constant-initializer which shall be an integral
11454 // constant expression (5.19). In that case, the member can appear
11455 // in integral constant expressions. The member shall still be
11456 // defined in a namespace scope if it is used in the program and the
11457 // namespace scope definition shall not contain an initializer.
11459 // We already performed a redefinition check above, but for static
11460 // data members we also need to check whether there was an in-class
11461 // declaration with an initializer.
11462 if (VDecl->isStaticDataMember() && VDecl->getCanonicalDecl()->hasInit()) {
11463 Diag(Init->getExprLoc(), diag::err_static_data_member_reinitialization)
11464 << VDecl->getDeclName();
11465 Diag(VDecl->getCanonicalDecl()->getInit()->getExprLoc(),
11466 diag::note_previous_initializer)
11471 if (VDecl->hasLocalStorage())
11472 setFunctionHasBranchProtectedScope();
11474 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) {
11475 VDecl->setInvalidDecl();
11480 // OpenCL 1.1 6.5.2: "Variables allocated in the __local address space inside
11481 // a kernel function cannot be initialized."
11482 if (VDecl->getType().getAddressSpace() == LangAS::opencl_local) {
11483 Diag(VDecl->getLocation(), diag::err_local_cant_init);
11484 VDecl->setInvalidDecl();
11488 // Get the decls type and save a reference for later, since
11489 // CheckInitializerTypes may change it.
11490 QualType DclT = VDecl->getType(), SavT = DclT;
11492 // Expressions default to 'id' when we're in a debugger
11493 // and we are assigning it to a variable of Objective-C pointer type.
11494 if (getLangOpts().DebuggerCastResultToId && DclT->isObjCObjectPointerType() &&
11495 Init->getType() == Context.UnknownAnyTy) {
11496 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
11497 if (Result.isInvalid()) {
11498 VDecl->setInvalidDecl();
11501 Init = Result.get();
11504 // Perform the initialization.
11505 ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
11506 if (!VDecl->isInvalidDecl()) {
11507 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
11508 InitializationKind Kind = InitializationKind::CreateForInit(
11509 VDecl->getLocation(), DirectInit, Init);
11511 MultiExprArg Args = Init;
11513 Args = MultiExprArg(CXXDirectInit->getExprs(),
11514 CXXDirectInit->getNumExprs());
11516 // Try to correct any TypoExprs in the initialization arguments.
11517 for (size_t Idx = 0; Idx < Args.size(); ++Idx) {
11518 ExprResult Res = CorrectDelayedTyposInExpr(
11519 Args[Idx], VDecl, [this, Entity, Kind](Expr *E) {
11520 InitializationSequence Init(*this, Entity, Kind, MultiExprArg(E));
11521 return Init.Failed() ? ExprError() : E;
11523 if (Res.isInvalid()) {
11524 VDecl->setInvalidDecl();
11525 } else if (Res.get() != Args[Idx]) {
11526 Args[Idx] = Res.get();
11529 if (VDecl->isInvalidDecl())
11532 InitializationSequence InitSeq(*this, Entity, Kind, Args,
11533 /*TopLevelOfInitList=*/false,
11534 /*TreatUnavailableAsInvalid=*/false);
11535 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
11536 if (Result.isInvalid()) {
11537 VDecl->setInvalidDecl();
11541 Init = Result.getAs<Expr>();
11544 // Check for self-references within variable initializers.
11545 // Variables declared within a function/method body (except for references)
11546 // are handled by a dataflow analysis.
11547 // This is undefined behavior in C++, but valid in C.
11548 if (getLangOpts().CPlusPlus) {
11549 if (!VDecl->hasLocalStorage() || VDecl->getType()->isRecordType() ||
11550 VDecl->getType()->isReferenceType()) {
11551 CheckSelfReference(*this, RealDecl, Init, DirectInit);
11555 // If the type changed, it means we had an incomplete type that was
11556 // completed by the initializer. For example:
11557 // int ary[] = { 1, 3, 5 };
11558 // "ary" transitions from an IncompleteArrayType to a ConstantArrayType.
11559 if (!VDecl->isInvalidDecl() && (DclT != SavT))
11560 VDecl->setType(DclT);
11562 if (!VDecl->isInvalidDecl()) {
11563 checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init);
11565 if (VDecl->hasAttr<BlocksAttr>())
11566 checkRetainCycles(VDecl, Init);
11568 // It is safe to assign a weak reference into a strong variable.
11569 // Although this code can still have problems:
11570 // id x = self.weakProp;
11571 // id y = self.weakProp;
11572 // we do not warn to warn spuriously when 'x' and 'y' are on separate
11573 // paths through the function. This should be revisited if
11574 // -Wrepeated-use-of-weak is made flow-sensitive.
11575 if (FunctionScopeInfo *FSI = getCurFunction())
11576 if ((VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong ||
11577 VDecl->getType().isNonWeakInMRRWithObjCWeak(Context)) &&
11578 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
11579 Init->getBeginLoc()))
11580 FSI->markSafeWeakUse(Init);
11583 // The initialization is usually a full-expression.
11585 // FIXME: If this is a braced initialization of an aggregate, it is not
11586 // an expression, and each individual field initializer is a separate
11587 // full-expression. For instance, in:
11589 // struct Temp { ~Temp(); };
11590 // struct S { S(Temp); };
11591 // struct T { S a, b; } t = { Temp(), Temp() }
11593 // we should destroy the first Temp before constructing the second.
11594 ExprResult Result =
11595 ActOnFinishFullExpr(Init, VDecl->getLocation(),
11596 /*DiscardedValue*/ false, VDecl->isConstexpr());
11597 if (Result.isInvalid()) {
11598 VDecl->setInvalidDecl();
11601 Init = Result.get();
11603 // Attach the initializer to the decl.
11604 VDecl->setInit(Init);
11606 if (VDecl->isLocalVarDecl()) {
11607 // Don't check the initializer if the declaration is malformed.
11608 if (VDecl->isInvalidDecl()) {
11611 // OpenCL v1.2 s6.5.3: __constant locals must be constant-initialized.
11612 // This is true even in C++ for OpenCL.
11613 } else if (VDecl->getType().getAddressSpace() == LangAS::opencl_constant) {
11614 CheckForConstantInitializer(Init, DclT);
11616 // Otherwise, C++ does not restrict the initializer.
11617 } else if (getLangOpts().CPlusPlus) {
11620 // C99 6.7.8p4: All the expressions in an initializer for an object that has
11621 // static storage duration shall be constant expressions or string literals.
11622 } else if (VDecl->getStorageClass() == SC_Static) {
11623 CheckForConstantInitializer(Init, DclT);
11625 // C89 is stricter than C99 for aggregate initializers.
11626 // C89 6.5.7p3: All the expressions [...] in an initializer list
11627 // for an object that has aggregate or union type shall be
11628 // constant expressions.
11629 } else if (!getLangOpts().C99 && VDecl->getType()->isAggregateType() &&
11630 isa<InitListExpr>(Init)) {
11631 const Expr *Culprit;
11632 if (!Init->isConstantInitializer(Context, false, &Culprit)) {
11633 Diag(Culprit->getExprLoc(),
11634 diag::ext_aggregate_init_not_constant)
11635 << Culprit->getSourceRange();
11639 if (auto *E = dyn_cast<ExprWithCleanups>(Init))
11640 if (auto *BE = dyn_cast<BlockExpr>(E->getSubExpr()->IgnoreParens()))
11641 if (VDecl->hasLocalStorage())
11642 BE->getBlockDecl()->setCanAvoidCopyToHeap();
11643 } else if (VDecl->isStaticDataMember() && !VDecl->isInline() &&
11644 VDecl->getLexicalDeclContext()->isRecord()) {
11645 // This is an in-class initialization for a static data member, e.g.,
11648 // static const int value = 17;
11651 // C++ [class.mem]p4:
11652 // A member-declarator can contain a constant-initializer only
11653 // if it declares a static member (9.4) of const integral or
11654 // const enumeration type, see 9.4.2.
11656 // C++11 [class.static.data]p3:
11657 // If a non-volatile non-inline const static data member is of integral
11658 // or enumeration type, its declaration in the class definition can
11659 // specify a brace-or-equal-initializer in which every initializer-clause
11660 // that is an assignment-expression is a constant expression. A static
11661 // data member of literal type can be declared in the class definition
11662 // with the constexpr specifier; if so, its declaration shall specify a
11663 // brace-or-equal-initializer in which every initializer-clause that is
11664 // an assignment-expression is a constant expression.
11666 // Do nothing on dependent types.
11667 if (DclT->isDependentType()) {
11669 // Allow any 'static constexpr' members, whether or not they are of literal
11670 // type. We separately check that every constexpr variable is of literal
11672 } else if (VDecl->isConstexpr()) {
11674 // Require constness.
11675 } else if (!DclT.isConstQualified()) {
11676 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const)
11677 << Init->getSourceRange();
11678 VDecl->setInvalidDecl();
11680 // We allow integer constant expressions in all cases.
11681 } else if (DclT->isIntegralOrEnumerationType()) {
11682 // Check whether the expression is a constant expression.
11683 SourceLocation Loc;
11684 if (getLangOpts().CPlusPlus11 && DclT.isVolatileQualified())
11685 // In C++11, a non-constexpr const static data member with an
11686 // in-class initializer cannot be volatile.
11687 Diag(VDecl->getLocation(), diag::err_in_class_initializer_volatile);
11688 else if (Init->isValueDependent())
11689 ; // Nothing to check.
11690 else if (Init->isIntegerConstantExpr(Context, &Loc))
11691 ; // Ok, it's an ICE!
11692 else if (Init->getType()->isScopedEnumeralType() &&
11693 Init->isCXX11ConstantExpr(Context))
11694 ; // Ok, it is a scoped-enum constant expression.
11695 else if (Init->isEvaluatable(Context)) {
11696 // If we can constant fold the initializer through heroics, accept it,
11697 // but report this as a use of an extension for -pedantic.
11698 Diag(Loc, diag::ext_in_class_initializer_non_constant)
11699 << Init->getSourceRange();
11701 // Otherwise, this is some crazy unknown case. Report the issue at the
11702 // location provided by the isIntegerConstantExpr failed check.
11703 Diag(Loc, diag::err_in_class_initializer_non_constant)
11704 << Init->getSourceRange();
11705 VDecl->setInvalidDecl();
11708 // We allow foldable floating-point constants as an extension.
11709 } else if (DclT->isFloatingType()) { // also permits complex, which is ok
11710 // In C++98, this is a GNU extension. In C++11, it is not, but we support
11711 // it anyway and provide a fixit to add the 'constexpr'.
11712 if (getLangOpts().CPlusPlus11) {
11713 Diag(VDecl->getLocation(),
11714 diag::ext_in_class_initializer_float_type_cxx11)
11715 << DclT << Init->getSourceRange();
11716 Diag(VDecl->getBeginLoc(),
11717 diag::note_in_class_initializer_float_type_cxx11)
11718 << FixItHint::CreateInsertion(VDecl->getBeginLoc(), "constexpr ");
11720 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type)
11721 << DclT << Init->getSourceRange();
11723 if (!Init->isValueDependent() && !Init->isEvaluatable(Context)) {
11724 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant)
11725 << Init->getSourceRange();
11726 VDecl->setInvalidDecl();
11730 // Suggest adding 'constexpr' in C++11 for literal types.
11731 } else if (getLangOpts().CPlusPlus11 && DclT->isLiteralType(Context)) {
11732 Diag(VDecl->getLocation(), diag::err_in_class_initializer_literal_type)
11733 << DclT << Init->getSourceRange()
11734 << FixItHint::CreateInsertion(VDecl->getBeginLoc(), "constexpr ");
11735 VDecl->setConstexpr(true);
11738 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type)
11739 << DclT << Init->getSourceRange();
11740 VDecl->setInvalidDecl();
11742 } else if (VDecl->isFileVarDecl()) {
11743 // In C, extern is typically used to avoid tentative definitions when
11744 // declaring variables in headers, but adding an intializer makes it a
11745 // definition. This is somewhat confusing, so GCC and Clang both warn on it.
11746 // In C++, extern is often used to give implictly static const variables
11747 // external linkage, so don't warn in that case. If selectany is present,
11748 // this might be header code intended for C and C++ inclusion, so apply the
11750 if (VDecl->getStorageClass() == SC_Extern &&
11751 ((!getLangOpts().CPlusPlus && !VDecl->hasAttr<SelectAnyAttr>()) ||
11752 !Context.getBaseElementType(VDecl->getType()).isConstQualified()) &&
11753 !(getLangOpts().CPlusPlus && VDecl->isExternC()) &&
11754 !isTemplateInstantiation(VDecl->getTemplateSpecializationKind()))
11755 Diag(VDecl->getLocation(), diag::warn_extern_init);
11757 // In Microsoft C++ mode, a const variable defined in namespace scope has
11758 // external linkage by default if the variable is declared with
11759 // __declspec(dllexport).
11760 if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
11761 getLangOpts().CPlusPlus && VDecl->getType().isConstQualified() &&
11762 VDecl->hasAttr<DLLExportAttr>() && VDecl->getDefinition())
11763 VDecl->setStorageClass(SC_Extern);
11765 // C99 6.7.8p4. All file scoped initializers need to be constant.
11766 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl())
11767 CheckForConstantInitializer(Init, DclT);
11770 QualType InitType = Init->getType();
11771 if (!InitType.isNull() &&
11772 (InitType.hasNonTrivialToPrimitiveDefaultInitializeCUnion() ||
11773 InitType.hasNonTrivialToPrimitiveCopyCUnion()))
11774 checkNonTrivialCUnionInInitializer(Init, Init->getExprLoc());
11776 // We will represent direct-initialization similarly to copy-initialization:
11777 // int x(1); -as-> int x = 1;
11778 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c);
11780 // Clients that want to distinguish between the two forms, can check for
11781 // direct initializer using VarDecl::getInitStyle().
11782 // A major benefit is that clients that don't particularly care about which
11783 // exactly form was it (like the CodeGen) can handle both cases without
11784 // special case code.
11787 // The form of initialization (using parentheses or '=') is generally
11788 // insignificant, but does matter when the entity being initialized has a
11790 if (CXXDirectInit) {
11791 assert(DirectInit && "Call-style initializer must be direct init.");
11792 VDecl->setInitStyle(VarDecl::CallInit);
11793 } else if (DirectInit) {
11794 // This must be list-initialization. No other way is direct-initialization.
11795 VDecl->setInitStyle(VarDecl::ListInit);
11798 CheckCompleteVariableDeclaration(VDecl);
11801 /// ActOnInitializerError - Given that there was an error parsing an
11802 /// initializer for the given declaration, try to return to some form
11804 void Sema::ActOnInitializerError(Decl *D) {
11805 // Our main concern here is re-establishing invariants like "a
11806 // variable's type is either dependent or complete".
11807 if (!D || D->isInvalidDecl()) return;
11809 VarDecl *VD = dyn_cast<VarDecl>(D);
11812 // Bindings are not usable if we can't make sense of the initializer.
11813 if (auto *DD = dyn_cast<DecompositionDecl>(D))
11814 for (auto *BD : DD->bindings())
11815 BD->setInvalidDecl();
11817 // Auto types are meaningless if we can't make sense of the initializer.
11818 if (ParsingInitForAutoVars.count(D)) {
11819 D->setInvalidDecl();
11823 QualType Ty = VD->getType();
11824 if (Ty->isDependentType()) return;
11826 // Require a complete type.
11827 if (RequireCompleteType(VD->getLocation(),
11828 Context.getBaseElementType(Ty),
11829 diag::err_typecheck_decl_incomplete_type)) {
11830 VD->setInvalidDecl();
11834 // Require a non-abstract type.
11835 if (RequireNonAbstractType(VD->getLocation(), Ty,
11836 diag::err_abstract_type_in_decl,
11837 AbstractVariableType)) {
11838 VD->setInvalidDecl();
11842 // Don't bother complaining about constructors or destructors,
11846 void Sema::ActOnUninitializedDecl(Decl *RealDecl) {
11847 // If there is no declaration, there was an error parsing it. Just ignore it.
11851 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) {
11852 QualType Type = Var->getType();
11854 // C++1z [dcl.dcl]p1 grammar implies that an initializer is mandatory.
11855 if (isa<DecompositionDecl>(RealDecl)) {
11856 Diag(Var->getLocation(), diag::err_decomp_decl_requires_init) << Var;
11857 Var->setInvalidDecl();
11861 if (Type->isUndeducedType() &&
11862 DeduceVariableDeclarationType(Var, false, nullptr))
11865 // C++11 [class.static.data]p3: A static data member can be declared with
11866 // the constexpr specifier; if so, its declaration shall specify
11867 // a brace-or-equal-initializer.
11868 // C++11 [dcl.constexpr]p1: The constexpr specifier shall be applied only to
11869 // the definition of a variable [...] or the declaration of a static data
11871 if (Var->isConstexpr() && !Var->isThisDeclarationADefinition() &&
11872 !Var->isThisDeclarationADemotedDefinition()) {
11873 if (Var->isStaticDataMember()) {
11874 // C++1z removes the relevant rule; the in-class declaration is always
11875 // a definition there.
11876 if (!getLangOpts().CPlusPlus17) {
11877 Diag(Var->getLocation(),
11878 diag::err_constexpr_static_mem_var_requires_init)
11879 << Var->getDeclName();
11880 Var->setInvalidDecl();
11884 Diag(Var->getLocation(), diag::err_invalid_constexpr_var_decl);
11885 Var->setInvalidDecl();
11890 // OpenCL v1.1 s6.5.3: variables declared in the constant address space must
11892 if (!Var->isInvalidDecl() &&
11893 Var->getType().getAddressSpace() == LangAS::opencl_constant &&
11894 Var->getStorageClass() != SC_Extern && !Var->getInit()) {
11895 Diag(Var->getLocation(), diag::err_opencl_constant_no_init);
11896 Var->setInvalidDecl();
11900 VarDecl::DefinitionKind DefKind = Var->isThisDeclarationADefinition();
11901 if (!Var->isInvalidDecl() && DefKind != VarDecl::DeclarationOnly &&
11902 Var->getType().hasNonTrivialToPrimitiveDefaultInitializeCUnion())
11903 checkNonTrivialCUnion(Var->getType(), Var->getLocation(),
11904 NTCUC_DefaultInitializedObject, NTCUK_Init);
11908 case VarDecl::Definition:
11909 if (!Var->isStaticDataMember() || !Var->getAnyInitializer())
11912 // We have an out-of-line definition of a static data member
11913 // that has an in-class initializer, so we type-check this like
11918 case VarDecl::DeclarationOnly:
11919 // It's only a declaration.
11921 // Block scope. C99 6.7p7: If an identifier for an object is
11922 // declared with no linkage (C99 6.2.2p6), the type for the
11923 // object shall be complete.
11924 if (!Type->isDependentType() && Var->isLocalVarDecl() &&
11925 !Var->hasLinkage() && !Var->isInvalidDecl() &&
11926 RequireCompleteType(Var->getLocation(), Type,
11927 diag::err_typecheck_decl_incomplete_type))
11928 Var->setInvalidDecl();
11930 // Make sure that the type is not abstract.
11931 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
11932 RequireNonAbstractType(Var->getLocation(), Type,
11933 diag::err_abstract_type_in_decl,
11934 AbstractVariableType))
11935 Var->setInvalidDecl();
11936 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
11937 Var->getStorageClass() == SC_PrivateExtern) {
11938 Diag(Var->getLocation(), diag::warn_private_extern);
11939 Diag(Var->getLocation(), diag::note_private_extern);
11944 case VarDecl::TentativeDefinition:
11945 // File scope. C99 6.9.2p2: A declaration of an identifier for an
11946 // object that has file scope without an initializer, and without a
11947 // storage-class specifier or with the storage-class specifier "static",
11948 // constitutes a tentative definition. Note: A tentative definition with
11949 // external linkage is valid (C99 6.2.2p5).
11950 if (!Var->isInvalidDecl()) {
11951 if (const IncompleteArrayType *ArrayT
11952 = Context.getAsIncompleteArrayType(Type)) {
11953 if (RequireCompleteType(Var->getLocation(),
11954 ArrayT->getElementType(),
11955 diag::err_illegal_decl_array_incomplete_type))
11956 Var->setInvalidDecl();
11957 } else if (Var->getStorageClass() == SC_Static) {
11958 // C99 6.9.2p3: If the declaration of an identifier for an object is
11959 // a tentative definition and has internal linkage (C99 6.2.2p3), the
11960 // declared type shall not be an incomplete type.
11961 // NOTE: code such as the following
11962 // static struct s;
11963 // struct s { int a; };
11964 // is accepted by gcc. Hence here we issue a warning instead of
11965 // an error and we do not invalidate the static declaration.
11966 // NOTE: to avoid multiple warnings, only check the first declaration.
11967 if (Var->isFirstDecl())
11968 RequireCompleteType(Var->getLocation(), Type,
11969 diag::ext_typecheck_decl_incomplete_type);
11973 // Record the tentative definition; we're done.
11974 if (!Var->isInvalidDecl())
11975 TentativeDefinitions.push_back(Var);
11979 // Provide a specific diagnostic for uninitialized variable
11980 // definitions with incomplete array type.
11981 if (Type->isIncompleteArrayType()) {
11982 Diag(Var->getLocation(),
11983 diag::err_typecheck_incomplete_array_needs_initializer);
11984 Var->setInvalidDecl();
11988 // Provide a specific diagnostic for uninitialized variable
11989 // definitions with reference type.
11990 if (Type->isReferenceType()) {
11991 Diag(Var->getLocation(), diag::err_reference_var_requires_init)
11992 << Var->getDeclName()
11993 << SourceRange(Var->getLocation(), Var->getLocation());
11994 Var->setInvalidDecl();
11998 // Do not attempt to type-check the default initializer for a
11999 // variable with dependent type.
12000 if (Type->isDependentType())
12003 if (Var->isInvalidDecl())
12006 if (!Var->hasAttr<AliasAttr>()) {
12007 if (RequireCompleteType(Var->getLocation(),
12008 Context.getBaseElementType(Type),
12009 diag::err_typecheck_decl_incomplete_type)) {
12010 Var->setInvalidDecl();
12017 // The variable can not have an abstract class type.
12018 if (RequireNonAbstractType(Var->getLocation(), Type,
12019 diag::err_abstract_type_in_decl,
12020 AbstractVariableType)) {
12021 Var->setInvalidDecl();
12025 // Check for jumps past the implicit initializer. C++0x
12026 // clarifies that this applies to a "variable with automatic
12027 // storage duration", not a "local variable".
12028 // C++11 [stmt.dcl]p3
12029 // A program that jumps from a point where a variable with automatic
12030 // storage duration is not in scope to a point where it is in scope is
12031 // ill-formed unless the variable has scalar type, class type with a
12032 // trivial default constructor and a trivial destructor, a cv-qualified
12033 // version of one of these types, or an array of one of the preceding
12034 // types and is declared without an initializer.
12035 if (getLangOpts().CPlusPlus && Var->hasLocalStorage()) {
12036 if (const RecordType *Record
12037 = Context.getBaseElementType(Type)->getAs<RecordType>()) {
12038 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl());
12039 // Mark the function (if we're in one) for further checking even if the
12040 // looser rules of C++11 do not require such checks, so that we can
12041 // diagnose incompatibilities with C++98.
12042 if (!CXXRecord->isPOD())
12043 setFunctionHasBranchProtectedScope();
12046 // In OpenCL, we can't initialize objects in the __local address space,
12047 // even implicitly, so don't synthesize an implicit initializer.
12048 if (getLangOpts().OpenCL &&
12049 Var->getType().getAddressSpace() == LangAS::opencl_local)
12051 // C++03 [dcl.init]p9:
12052 // If no initializer is specified for an object, and the
12053 // object is of (possibly cv-qualified) non-POD class type (or
12054 // array thereof), the object shall be default-initialized; if
12055 // the object is of const-qualified type, the underlying class
12056 // type shall have a user-declared default
12057 // constructor. Otherwise, if no initializer is specified for
12058 // a non- static object, the object and its subobjects, if
12059 // any, have an indeterminate initial value); if the object
12060 // or any of its subobjects are of const-qualified type, the
12061 // program is ill-formed.
12062 // C++0x [dcl.init]p11:
12063 // If no initializer is specified for an object, the object is
12064 // default-initialized; [...].
12065 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var);
12066 InitializationKind Kind
12067 = InitializationKind::CreateDefault(Var->getLocation());
12069 InitializationSequence InitSeq(*this, Entity, Kind, None);
12070 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, None);
12071 if (Init.isInvalid())
12072 Var->setInvalidDecl();
12073 else if (Init.get()) {
12074 Var->setInit(MaybeCreateExprWithCleanups(Init.get()));
12075 // This is important for template substitution.
12076 Var->setInitStyle(VarDecl::CallInit);
12079 CheckCompleteVariableDeclaration(Var);
12083 void Sema::ActOnCXXForRangeDecl(Decl *D) {
12084 // If there is no declaration, there was an error parsing it. Ignore it.
12088 VarDecl *VD = dyn_cast<VarDecl>(D);
12090 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var);
12091 D->setInvalidDecl();
12095 VD->setCXXForRangeDecl(true);
12097 // for-range-declaration cannot be given a storage class specifier.
12099 switch (VD->getStorageClass()) {
12108 case SC_PrivateExtern:
12119 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class)
12120 << VD->getDeclName() << Error;
12121 D->setInvalidDecl();
12126 Sema::ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
12127 IdentifierInfo *Ident,
12128 ParsedAttributes &Attrs,
12129 SourceLocation AttrEnd) {
12130 // C++1y [stmt.iter]p1:
12131 // A range-based for statement of the form
12132 // for ( for-range-identifier : for-range-initializer ) statement
12133 // is equivalent to
12134 // for ( auto&& for-range-identifier : for-range-initializer ) statement
12135 DeclSpec DS(Attrs.getPool().getFactory());
12137 const char *PrevSpec;
12139 DS.SetTypeSpecType(DeclSpec::TST_auto, IdentLoc, PrevSpec, DiagID,
12140 getPrintingPolicy());
12142 Declarator D(DS, DeclaratorContext::ForContext);
12143 D.SetIdentifier(Ident, IdentLoc);
12144 D.takeAttributes(Attrs, AttrEnd);
12146 D.AddTypeInfo(DeclaratorChunk::getReference(0, IdentLoc, /*lvalue*/ false),
12148 Decl *Var = ActOnDeclarator(S, D);
12149 cast<VarDecl>(Var)->setCXXForRangeDecl(true);
12150 FinalizeDeclaration(Var);
12151 return ActOnDeclStmt(FinalizeDeclaratorGroup(S, DS, Var), IdentLoc,
12152 AttrEnd.isValid() ? AttrEnd : IdentLoc);
12155 void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
12156 if (var->isInvalidDecl()) return;
12158 if (getLangOpts().OpenCL) {
12159 // OpenCL v2.0 s6.12.5 - Every block variable declaration must have an
12161 if (var->getTypeSourceInfo()->getType()->isBlockPointerType() &&
12163 Diag(var->getLocation(), diag::err_opencl_invalid_block_declaration)
12165 var->setInvalidDecl();
12170 // In Objective-C, don't allow jumps past the implicit initialization of a
12171 // local retaining variable.
12172 if (getLangOpts().ObjC &&
12173 var->hasLocalStorage()) {
12174 switch (var->getType().getObjCLifetime()) {
12175 case Qualifiers::OCL_None:
12176 case Qualifiers::OCL_ExplicitNone:
12177 case Qualifiers::OCL_Autoreleasing:
12180 case Qualifiers::OCL_Weak:
12181 case Qualifiers::OCL_Strong:
12182 setFunctionHasBranchProtectedScope();
12187 if (var->hasLocalStorage() &&
12188 var->getType().isDestructedType() == QualType::DK_nontrivial_c_struct)
12189 setFunctionHasBranchProtectedScope();
12191 // Warn about externally-visible variables being defined without a
12192 // prior declaration. We only want to do this for global
12193 // declarations, but we also specifically need to avoid doing it for
12194 // class members because the linkage of an anonymous class can
12195 // change if it's later given a typedef name.
12196 if (var->isThisDeclarationADefinition() &&
12197 var->getDeclContext()->getRedeclContext()->isFileContext() &&
12198 var->isExternallyVisible() && var->hasLinkage() &&
12199 !var->isInline() && !var->getDescribedVarTemplate() &&
12200 !isTemplateInstantiation(var->getTemplateSpecializationKind()) &&
12201 !getDiagnostics().isIgnored(diag::warn_missing_variable_declarations,
12202 var->getLocation())) {
12203 // Find a previous declaration that's not a definition.
12204 VarDecl *prev = var->getPreviousDecl();
12205 while (prev && prev->isThisDeclarationADefinition())
12206 prev = prev->getPreviousDecl();
12209 Diag(var->getLocation(), diag::warn_missing_variable_declarations) << var;
12210 Diag(var->getTypeSpecStartLoc(), diag::note_static_for_internal_linkage)
12211 << /* variable */ 0;
12215 // Cache the result of checking for constant initialization.
12216 Optional<bool> CacheHasConstInit;
12217 const Expr *CacheCulprit = nullptr;
12218 auto checkConstInit = [&]() mutable {
12219 if (!CacheHasConstInit)
12220 CacheHasConstInit = var->getInit()->isConstantInitializer(
12221 Context, var->getType()->isReferenceType(), &CacheCulprit);
12222 return *CacheHasConstInit;
12225 if (var->getTLSKind() == VarDecl::TLS_Static) {
12226 if (var->getType().isDestructedType()) {
12227 // GNU C++98 edits for __thread, [basic.start.term]p3:
12228 // The type of an object with thread storage duration shall not
12229 // have a non-trivial destructor.
12230 Diag(var->getLocation(), diag::err_thread_nontrivial_dtor);
12231 if (getLangOpts().CPlusPlus11)
12232 Diag(var->getLocation(), diag::note_use_thread_local);
12233 } else if (getLangOpts().CPlusPlus && var->hasInit()) {
12234 if (!checkConstInit()) {
12235 // GNU C++98 edits for __thread, [basic.start.init]p4:
12236 // An object of thread storage duration shall not require dynamic
12238 // FIXME: Need strict checking here.
12239 Diag(CacheCulprit->getExprLoc(), diag::err_thread_dynamic_init)
12240 << CacheCulprit->getSourceRange();
12241 if (getLangOpts().CPlusPlus11)
12242 Diag(var->getLocation(), diag::note_use_thread_local);
12247 // Apply section attributes and pragmas to global variables.
12248 bool GlobalStorage = var->hasGlobalStorage();
12249 if (GlobalStorage && var->isThisDeclarationADefinition() &&
12250 !inTemplateInstantiation()) {
12251 PragmaStack<StringLiteral *> *Stack = nullptr;
12252 int SectionFlags = ASTContext::PSF_Implicit | ASTContext::PSF_Read;
12253 if (var->getType().isConstQualified())
12254 Stack = &ConstSegStack;
12255 else if (!var->getInit()) {
12256 Stack = &BSSSegStack;
12257 SectionFlags |= ASTContext::PSF_Write;
12259 Stack = &DataSegStack;
12260 SectionFlags |= ASTContext::PSF_Write;
12262 if (Stack->CurrentValue && !var->hasAttr<SectionAttr>()) {
12263 var->addAttr(SectionAttr::CreateImplicit(
12264 Context, SectionAttr::Declspec_allocate,
12265 Stack->CurrentValue->getString(), Stack->CurrentPragmaLocation));
12267 if (const SectionAttr *SA = var->getAttr<SectionAttr>())
12268 if (UnifySection(SA->getName(), SectionFlags, var))
12269 var->dropAttr<SectionAttr>();
12271 // Apply the init_seg attribute if this has an initializer. If the
12272 // initializer turns out to not be dynamic, we'll end up ignoring this
12274 if (CurInitSeg && var->getInit())
12275 var->addAttr(InitSegAttr::CreateImplicit(Context, CurInitSeg->getString(),
12279 // All the following checks are C++ only.
12280 if (!getLangOpts().CPlusPlus) {
12281 // If this variable must be emitted, add it as an initializer for the
12283 if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
12284 Context.addModuleInitializer(ModuleScopes.back().Module, var);
12288 if (auto *DD = dyn_cast<DecompositionDecl>(var))
12289 CheckCompleteDecompositionDeclaration(DD);
12291 QualType type = var->getType();
12292 if (type->isDependentType()) return;
12294 if (var->hasAttr<BlocksAttr>())
12295 getCurFunction()->addByrefBlockVar(var);
12297 Expr *Init = var->getInit();
12298 bool IsGlobal = GlobalStorage && !var->isStaticLocal();
12299 QualType baseType = Context.getBaseElementType(type);
12301 if (Init && !Init->isValueDependent()) {
12302 if (var->isConstexpr()) {
12303 SmallVector<PartialDiagnosticAt, 8> Notes;
12304 if (!var->evaluateValue(Notes) || !var->isInitICE()) {
12305 SourceLocation DiagLoc = var->getLocation();
12306 // If the note doesn't add any useful information other than a source
12307 // location, fold it into the primary diagnostic.
12308 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
12309 diag::note_invalid_subexpr_in_const_expr) {
12310 DiagLoc = Notes[0].first;
12313 Diag(DiagLoc, diag::err_constexpr_var_requires_const_init)
12314 << var << Init->getSourceRange();
12315 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
12316 Diag(Notes[I].first, Notes[I].second);
12318 } else if (var->mightBeUsableInConstantExpressions(Context)) {
12319 // Check whether the initializer of a const variable of integral or
12320 // enumeration type is an ICE now, since we can't tell whether it was
12321 // initialized by a constant expression if we check later.
12322 var->checkInitIsICE();
12325 // Don't emit further diagnostics about constexpr globals since they
12326 // were just diagnosed.
12327 if (!var->isConstexpr() && GlobalStorage &&
12328 var->hasAttr<RequireConstantInitAttr>()) {
12329 // FIXME: Need strict checking in C++03 here.
12330 bool DiagErr = getLangOpts().CPlusPlus11
12331 ? !var->checkInitIsICE() : !checkConstInit();
12333 auto attr = var->getAttr<RequireConstantInitAttr>();
12334 Diag(var->getLocation(), diag::err_require_constant_init_failed)
12335 << Init->getSourceRange();
12336 Diag(attr->getLocation(), diag::note_declared_required_constant_init_here)
12337 << attr->getRange();
12338 if (getLangOpts().CPlusPlus11) {
12340 SmallVector<PartialDiagnosticAt, 8> Notes;
12341 Init->EvaluateAsInitializer(Value, getASTContext(), var, Notes);
12342 for (auto &it : Notes)
12343 Diag(it.first, it.second);
12345 Diag(CacheCulprit->getExprLoc(),
12346 diag::note_invalid_subexpr_in_const_expr)
12347 << CacheCulprit->getSourceRange();
12351 else if (!var->isConstexpr() && IsGlobal &&
12352 !getDiagnostics().isIgnored(diag::warn_global_constructor,
12353 var->getLocation())) {
12354 // Warn about globals which don't have a constant initializer. Don't
12355 // warn about globals with a non-trivial destructor because we already
12356 // warned about them.
12357 CXXRecordDecl *RD = baseType->getAsCXXRecordDecl();
12358 if (!(RD && !RD->hasTrivialDestructor())) {
12359 if (!checkConstInit())
12360 Diag(var->getLocation(), diag::warn_global_constructor)
12361 << Init->getSourceRange();
12366 // Require the destructor.
12367 if (const RecordType *recordType = baseType->getAs<RecordType>())
12368 FinalizeVarWithDestructor(var, recordType);
12370 // If this variable must be emitted, add it as an initializer for the current
12372 if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
12373 Context.addModuleInitializer(ModuleScopes.back().Module, var);
12376 /// Determines if a variable's alignment is dependent.
12377 static bool hasDependentAlignment(VarDecl *VD) {
12378 if (VD->getType()->isDependentType())
12380 for (auto *I : VD->specific_attrs<AlignedAttr>())
12381 if (I->isAlignmentDependent())
12386 /// Check if VD needs to be dllexport/dllimport due to being in a
12387 /// dllexport/import function.
12388 void Sema::CheckStaticLocalForDllExport(VarDecl *VD) {
12389 assert(VD->isStaticLocal());
12391 auto *FD = dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod());
12393 // Find outermost function when VD is in lambda function.
12394 while (FD && !getDLLAttr(FD) &&
12395 !FD->hasAttr<DLLExportStaticLocalAttr>() &&
12396 !FD->hasAttr<DLLImportStaticLocalAttr>()) {
12397 FD = dyn_cast_or_null<FunctionDecl>(FD->getParentFunctionOrMethod());
12403 // Static locals inherit dll attributes from their function.
12404 if (Attr *A = getDLLAttr(FD)) {
12405 auto *NewAttr = cast<InheritableAttr>(A->clone(getASTContext()));
12406 NewAttr->setInherited(true);
12407 VD->addAttr(NewAttr);
12408 } else if (Attr *A = FD->getAttr<DLLExportStaticLocalAttr>()) {
12409 auto *NewAttr = ::new (getASTContext()) DLLExportAttr(A->getRange(),
12411 A->getSpellingListIndex());
12412 NewAttr->setInherited(true);
12413 VD->addAttr(NewAttr);
12415 // Export this function to enforce exporting this static variable even
12416 // if it is not used in this compilation unit.
12417 if (!FD->hasAttr<DLLExportAttr>())
12418 FD->addAttr(NewAttr);
12420 } else if (Attr *A = FD->getAttr<DLLImportStaticLocalAttr>()) {
12421 auto *NewAttr = ::new (getASTContext()) DLLImportAttr(A->getRange(),
12423 A->getSpellingListIndex());
12424 NewAttr->setInherited(true);
12425 VD->addAttr(NewAttr);
12429 /// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform
12430 /// any semantic actions necessary after any initializer has been attached.
12431 void Sema::FinalizeDeclaration(Decl *ThisDecl) {
12432 // Note that we are no longer parsing the initializer for this declaration.
12433 ParsingInitForAutoVars.erase(ThisDecl);
12435 VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDecl);
12439 // Apply an implicit SectionAttr if '#pragma clang section bss|data|rodata' is active
12440 if (VD->hasGlobalStorage() && VD->isThisDeclarationADefinition() &&
12441 !inTemplateInstantiation() && !VD->hasAttr<SectionAttr>()) {
12442 if (PragmaClangBSSSection.Valid)
12443 VD->addAttr(PragmaClangBSSSectionAttr::CreateImplicit(Context,
12444 PragmaClangBSSSection.SectionName,
12445 PragmaClangBSSSection.PragmaLocation));
12446 if (PragmaClangDataSection.Valid)
12447 VD->addAttr(PragmaClangDataSectionAttr::CreateImplicit(Context,
12448 PragmaClangDataSection.SectionName,
12449 PragmaClangDataSection.PragmaLocation));
12450 if (PragmaClangRodataSection.Valid)
12451 VD->addAttr(PragmaClangRodataSectionAttr::CreateImplicit(Context,
12452 PragmaClangRodataSection.SectionName,
12453 PragmaClangRodataSection.PragmaLocation));
12456 if (auto *DD = dyn_cast<DecompositionDecl>(ThisDecl)) {
12457 for (auto *BD : DD->bindings()) {
12458 FinalizeDeclaration(BD);
12462 checkAttributesAfterMerging(*this, *VD);
12464 // Perform TLS alignment check here after attributes attached to the variable
12465 // which may affect the alignment have been processed. Only perform the check
12466 // if the target has a maximum TLS alignment (zero means no constraints).
12467 if (unsigned MaxAlign = Context.getTargetInfo().getMaxTLSAlign()) {
12468 // Protect the check so that it's not performed on dependent types and
12469 // dependent alignments (we can't determine the alignment in that case).
12470 if (VD->getTLSKind() && !hasDependentAlignment(VD) &&
12471 !VD->isInvalidDecl()) {
12472 CharUnits MaxAlignChars = Context.toCharUnitsFromBits(MaxAlign);
12473 if (Context.getDeclAlign(VD) > MaxAlignChars) {
12474 Diag(VD->getLocation(), diag::err_tls_var_aligned_over_maximum)
12475 << (unsigned)Context.getDeclAlign(VD).getQuantity() << VD
12476 << (unsigned)MaxAlignChars.getQuantity();
12481 if (VD->isStaticLocal()) {
12482 CheckStaticLocalForDllExport(VD);
12484 if (dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod())) {
12485 // CUDA 8.0 E.3.9.4: Within the body of a __device__ or __global__
12486 // function, only __shared__ variables or variables without any device
12487 // memory qualifiers may be declared with static storage class.
12488 // Note: It is unclear how a function-scope non-const static variable
12489 // without device memory qualifier is implemented, therefore only static
12490 // const variable without device memory qualifier is allowed.
12492 if (!getLangOpts().CUDA)
12494 if (VD->hasAttr<CUDASharedAttr>())
12496 if (VD->getType().isConstQualified() &&
12497 !(VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>()))
12499 if (CUDADiagIfDeviceCode(VD->getLocation(),
12500 diag::err_device_static_local_var)
12501 << CurrentCUDATarget())
12502 VD->setInvalidDecl();
12507 // Perform check for initializers of device-side global variables.
12508 // CUDA allows empty constructors as initializers (see E.2.3.1, CUDA
12509 // 7.5). We must also apply the same checks to all __shared__
12510 // variables whether they are local or not. CUDA also allows
12511 // constant initializers for __constant__ and __device__ variables.
12512 if (getLangOpts().CUDA)
12513 checkAllowedCUDAInitializer(VD);
12515 // Grab the dllimport or dllexport attribute off of the VarDecl.
12516 const InheritableAttr *DLLAttr = getDLLAttr(VD);
12518 // Imported static data members cannot be defined out-of-line.
12519 if (const auto *IA = dyn_cast_or_null<DLLImportAttr>(DLLAttr)) {
12520 if (VD->isStaticDataMember() && VD->isOutOfLine() &&
12521 VD->isThisDeclarationADefinition()) {
12522 // We allow definitions of dllimport class template static data members
12524 CXXRecordDecl *Context =
12525 cast<CXXRecordDecl>(VD->getFirstDecl()->getDeclContext());
12526 bool IsClassTemplateMember =
12527 isa<ClassTemplatePartialSpecializationDecl>(Context) ||
12528 Context->getDescribedClassTemplate();
12530 Diag(VD->getLocation(),
12531 IsClassTemplateMember
12532 ? diag::warn_attribute_dllimport_static_field_definition
12533 : diag::err_attribute_dllimport_static_field_definition);
12534 Diag(IA->getLocation(), diag::note_attribute);
12535 if (!IsClassTemplateMember)
12536 VD->setInvalidDecl();
12540 // dllimport/dllexport variables cannot be thread local, their TLS index
12541 // isn't exported with the variable.
12542 if (DLLAttr && VD->getTLSKind()) {
12543 auto *F = dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod());
12544 if (F && getDLLAttr(F)) {
12545 assert(VD->isStaticLocal());
12546 // But if this is a static local in a dlimport/dllexport function, the
12547 // function will never be inlined, which means the var would never be
12548 // imported, so having it marked import/export is safe.
12550 Diag(VD->getLocation(), diag::err_attribute_dll_thread_local) << VD
12552 VD->setInvalidDecl();
12556 if (UsedAttr *Attr = VD->getAttr<UsedAttr>()) {
12557 if (!Attr->isInherited() && !VD->isThisDeclarationADefinition()) {
12558 Diag(Attr->getLocation(), diag::warn_attribute_ignored) << Attr;
12559 VD->dropAttr<UsedAttr>();
12563 const DeclContext *DC = VD->getDeclContext();
12564 // If there's a #pragma GCC visibility in scope, and this isn't a class
12565 // member, set the visibility of this variable.
12566 if (DC->getRedeclContext()->isFileContext() && VD->isExternallyVisible())
12567 AddPushedVisibilityAttribute(VD);
12569 // FIXME: Warn on unused var template partial specializations.
12570 if (VD->isFileVarDecl() && !isa<VarTemplatePartialSpecializationDecl>(VD))
12571 MarkUnusedFileScopedDecl(VD);
12573 // Now we have parsed the initializer and can update the table of magic
12575 if (!VD->hasAttr<TypeTagForDatatypeAttr>() ||
12576 !VD->getType()->isIntegralOrEnumerationType())
12579 for (const auto *I : ThisDecl->specific_attrs<TypeTagForDatatypeAttr>()) {
12580 const Expr *MagicValueExpr = VD->getInit();
12581 if (!MagicValueExpr) {
12584 llvm::APSInt MagicValueInt;
12585 if (!MagicValueExpr->isIntegerConstantExpr(MagicValueInt, Context)) {
12586 Diag(I->getRange().getBegin(),
12587 diag::err_type_tag_for_datatype_not_ice)
12588 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
12591 if (MagicValueInt.getActiveBits() > 64) {
12592 Diag(I->getRange().getBegin(),
12593 diag::err_type_tag_for_datatype_too_large)
12594 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
12597 uint64_t MagicValue = MagicValueInt.getZExtValue();
12598 RegisterTypeTagForDatatype(I->getArgumentKind(),
12600 I->getMatchingCType(),
12601 I->getLayoutCompatible(),
12602 I->getMustBeNull());
12606 static bool hasDeducedAuto(DeclaratorDecl *DD) {
12607 auto *VD = dyn_cast<VarDecl>(DD);
12608 return VD && !VD->getType()->hasAutoForTrailingReturnType();
12611 Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
12612 ArrayRef<Decl *> Group) {
12613 SmallVector<Decl*, 8> Decls;
12615 if (DS.isTypeSpecOwned())
12616 Decls.push_back(DS.getRepAsDecl());
12618 DeclaratorDecl *FirstDeclaratorInGroup = nullptr;
12619 DecompositionDecl *FirstDecompDeclaratorInGroup = nullptr;
12620 bool DiagnosedMultipleDecomps = false;
12621 DeclaratorDecl *FirstNonDeducedAutoInGroup = nullptr;
12622 bool DiagnosedNonDeducedAuto = false;
12624 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
12625 if (Decl *D = Group[i]) {
12626 // For declarators, there are some additional syntactic-ish checks we need
12628 if (auto *DD = dyn_cast<DeclaratorDecl>(D)) {
12629 if (!FirstDeclaratorInGroup)
12630 FirstDeclaratorInGroup = DD;
12631 if (!FirstDecompDeclaratorInGroup)
12632 FirstDecompDeclaratorInGroup = dyn_cast<DecompositionDecl>(D);
12633 if (!FirstNonDeducedAutoInGroup && DS.hasAutoTypeSpec() &&
12634 !hasDeducedAuto(DD))
12635 FirstNonDeducedAutoInGroup = DD;
12637 if (FirstDeclaratorInGroup != DD) {
12638 // A decomposition declaration cannot be combined with any other
12639 // declaration in the same group.
12640 if (FirstDecompDeclaratorInGroup && !DiagnosedMultipleDecomps) {
12641 Diag(FirstDecompDeclaratorInGroup->getLocation(),
12642 diag::err_decomp_decl_not_alone)
12643 << FirstDeclaratorInGroup->getSourceRange()
12644 << DD->getSourceRange();
12645 DiagnosedMultipleDecomps = true;
12648 // A declarator that uses 'auto' in any way other than to declare a
12649 // variable with a deduced type cannot be combined with any other
12650 // declarator in the same group.
12651 if (FirstNonDeducedAutoInGroup && !DiagnosedNonDeducedAuto) {
12652 Diag(FirstNonDeducedAutoInGroup->getLocation(),
12653 diag::err_auto_non_deduced_not_alone)
12654 << FirstNonDeducedAutoInGroup->getType()
12655 ->hasAutoForTrailingReturnType()
12656 << FirstDeclaratorInGroup->getSourceRange()
12657 << DD->getSourceRange();
12658 DiagnosedNonDeducedAuto = true;
12663 Decls.push_back(D);
12667 if (DeclSpec::isDeclRep(DS.getTypeSpecType())) {
12668 if (TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) {
12669 handleTagNumbering(Tag, S);
12670 if (FirstDeclaratorInGroup && !Tag->hasNameForLinkage() &&
12671 getLangOpts().CPlusPlus)
12672 Context.addDeclaratorForUnnamedTagDecl(Tag, FirstDeclaratorInGroup);
12676 return BuildDeclaratorGroup(Decls);
12679 /// BuildDeclaratorGroup - convert a list of declarations into a declaration
12680 /// group, performing any necessary semantic checking.
12681 Sema::DeclGroupPtrTy
12682 Sema::BuildDeclaratorGroup(MutableArrayRef<Decl *> Group) {
12683 // C++14 [dcl.spec.auto]p7: (DR1347)
12684 // If the type that replaces the placeholder type is not the same in each
12685 // deduction, the program is ill-formed.
12686 if (Group.size() > 1) {
12688 VarDecl *DeducedDecl = nullptr;
12689 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
12690 VarDecl *D = dyn_cast<VarDecl>(Group[i]);
12691 if (!D || D->isInvalidDecl())
12693 DeducedType *DT = D->getType()->getContainedDeducedType();
12694 if (!DT || DT->getDeducedType().isNull())
12696 if (Deduced.isNull()) {
12697 Deduced = DT->getDeducedType();
12699 } else if (!Context.hasSameType(DT->getDeducedType(), Deduced)) {
12700 auto *AT = dyn_cast<AutoType>(DT);
12701 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(),
12702 diag::err_auto_different_deductions)
12703 << (AT ? (unsigned)AT->getKeyword() : 3)
12704 << Deduced << DeducedDecl->getDeclName()
12705 << DT->getDeducedType() << D->getDeclName()
12706 << DeducedDecl->getInit()->getSourceRange()
12707 << D->getInit()->getSourceRange();
12708 D->setInvalidDecl();
12714 ActOnDocumentableDecls(Group);
12716 return DeclGroupPtrTy::make(
12717 DeclGroupRef::Create(Context, Group.data(), Group.size()));
12720 void Sema::ActOnDocumentableDecl(Decl *D) {
12721 ActOnDocumentableDecls(D);
12724 void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) {
12725 // Don't parse the comment if Doxygen diagnostics are ignored.
12726 if (Group.empty() || !Group[0])
12729 if (Diags.isIgnored(diag::warn_doc_param_not_found,
12730 Group[0]->getLocation()) &&
12731 Diags.isIgnored(diag::warn_unknown_comment_command_name,
12732 Group[0]->getLocation()))
12735 if (Group.size() >= 2) {
12736 // This is a decl group. Normally it will contain only declarations
12737 // produced from declarator list. But in case we have any definitions or
12738 // additional declaration references:
12739 // 'typedef struct S {} S;'
12740 // 'typedef struct S *S;'
12742 // FinalizeDeclaratorGroup adds these as separate declarations.
12743 Decl *MaybeTagDecl = Group[0];
12744 if (MaybeTagDecl && isa<TagDecl>(MaybeTagDecl)) {
12745 Group = Group.slice(1);
12749 // See if there are any new comments that are not attached to a decl.
12750 ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments();
12751 if (!Comments.empty() &&
12752 !Comments.back()->isAttached()) {
12753 // There is at least one comment that not attached to a decl.
12754 // Maybe it should be attached to one of these decls?
12756 // Note that this way we pick up not only comments that precede the
12757 // declaration, but also comments that *follow* the declaration -- thanks to
12758 // the lookahead in the lexer: we've consumed the semicolon and looked
12759 // ahead through comments.
12760 for (unsigned i = 0, e = Group.size(); i != e; ++i)
12761 Context.getCommentForDecl(Group[i], &PP);
12765 /// Common checks for a parameter-declaration that should apply to both function
12766 /// parameters and non-type template parameters.
12767 void Sema::CheckFunctionOrTemplateParamDeclarator(Scope *S, Declarator &D) {
12768 // Check that there are no default arguments inside the type of this
12770 if (getLangOpts().CPlusPlus)
12771 CheckExtraCXXDefaultArguments(D);
12773 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
12774 if (D.getCXXScopeSpec().isSet()) {
12775 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator)
12776 << D.getCXXScopeSpec().getRange();
12779 // [dcl.meaning]p1: An unqualified-id occurring in a declarator-id shall be a
12780 // simple identifier except [...irrelevant cases...].
12781 switch (D.getName().getKind()) {
12782 case UnqualifiedIdKind::IK_Identifier:
12785 case UnqualifiedIdKind::IK_OperatorFunctionId:
12786 case UnqualifiedIdKind::IK_ConversionFunctionId:
12787 case UnqualifiedIdKind::IK_LiteralOperatorId:
12788 case UnqualifiedIdKind::IK_ConstructorName:
12789 case UnqualifiedIdKind::IK_DestructorName:
12790 case UnqualifiedIdKind::IK_ImplicitSelfParam:
12791 case UnqualifiedIdKind::IK_DeductionGuideName:
12792 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name)
12793 << GetNameForDeclarator(D).getName();
12796 case UnqualifiedIdKind::IK_TemplateId:
12797 case UnqualifiedIdKind::IK_ConstructorTemplateId:
12798 // GetNameForDeclarator would not produce a useful name in this case.
12799 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name_template_id);
12804 /// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator()
12805 /// to introduce parameters into function prototype scope.
12806 Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) {
12807 const DeclSpec &DS = D.getDeclSpec();
12809 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'.
12811 // C++03 [dcl.stc]p2 also permits 'auto'.
12812 StorageClass SC = SC_None;
12813 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
12815 // In C++11, the 'register' storage class specifier is deprecated.
12816 // In C++17, it is not allowed, but we tolerate it as an extension.
12817 if (getLangOpts().CPlusPlus11) {
12818 Diag(DS.getStorageClassSpecLoc(),
12819 getLangOpts().CPlusPlus17 ? diag::ext_register_storage_class
12820 : diag::warn_deprecated_register)
12821 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
12823 } else if (getLangOpts().CPlusPlus &&
12824 DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
12826 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) {
12827 Diag(DS.getStorageClassSpecLoc(),
12828 diag::err_invalid_storage_class_in_func_decl);
12829 D.getMutableDeclSpec().ClearStorageClassSpecs();
12832 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
12833 Diag(DS.getThreadStorageClassSpecLoc(), diag::err_invalid_thread)
12834 << DeclSpec::getSpecifierName(TSCS);
12835 if (DS.isInlineSpecified())
12836 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
12837 << getLangOpts().CPlusPlus17;
12838 if (DS.hasConstexprSpecifier())
12839 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr)
12840 << 0 << (D.getDeclSpec().getConstexprSpecifier() == CSK_consteval);
12842 DiagnoseFunctionSpecifiers(DS);
12844 CheckFunctionOrTemplateParamDeclarator(S, D);
12846 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
12847 QualType parmDeclType = TInfo->getType();
12849 // Check for redeclaration of parameters, e.g. int foo(int x, int x);
12850 IdentifierInfo *II = D.getIdentifier();
12852 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName,
12853 ForVisibleRedeclaration);
12855 if (R.isSingleResult()) {
12856 NamedDecl *PrevDecl = R.getFoundDecl();
12857 if (PrevDecl->isTemplateParameter()) {
12858 // Maybe we will complain about the shadowed template parameter.
12859 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
12860 // Just pretend that we didn't see the previous declaration.
12861 PrevDecl = nullptr;
12862 } else if (S->isDeclScope(PrevDecl)) {
12863 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II;
12864 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
12866 // Recover by removing the name
12868 D.SetIdentifier(nullptr, D.getIdentifierLoc());
12869 D.setInvalidType(true);
12874 // Temporarily put parameter variables in the translation unit, not
12875 // the enclosing context. This prevents them from accidentally
12876 // looking like class members in C++.
12878 CheckParameter(Context.getTranslationUnitDecl(), D.getBeginLoc(),
12879 D.getIdentifierLoc(), II, parmDeclType, TInfo, SC);
12881 if (D.isInvalidType())
12882 New->setInvalidDecl();
12884 assert(S->isFunctionPrototypeScope());
12885 assert(S->getFunctionPrototypeDepth() >= 1);
12886 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1,
12887 S->getNextFunctionPrototypeIndex());
12889 // Add the parameter declaration into this scope.
12892 IdResolver.AddDecl(New);
12894 ProcessDeclAttributes(S, New, D);
12896 if (D.getDeclSpec().isModulePrivateSpecified())
12897 Diag(New->getLocation(), diag::err_module_private_local)
12898 << 1 << New->getDeclName()
12899 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
12900 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
12902 if (New->hasAttr<BlocksAttr>()) {
12903 Diag(New->getLocation(), diag::err_block_on_nonlocal);
12908 /// Synthesizes a variable for a parameter arising from a
12910 ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC,
12911 SourceLocation Loc,
12913 /* FIXME: setting StartLoc == Loc.
12914 Would it be worth to modify callers so as to provide proper source
12915 location for the unnamed parameters, embedding the parameter's type? */
12916 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, nullptr,
12917 T, Context.getTrivialTypeSourceInfo(T, Loc),
12919 Param->setImplicit();
12923 void Sema::DiagnoseUnusedParameters(ArrayRef<ParmVarDecl *> Parameters) {
12924 // Don't diagnose unused-parameter errors in template instantiations; we
12925 // will already have done so in the template itself.
12926 if (inTemplateInstantiation())
12929 for (const ParmVarDecl *Parameter : Parameters) {
12930 if (!Parameter->isReferenced() && Parameter->getDeclName() &&
12931 !Parameter->hasAttr<UnusedAttr>()) {
12932 Diag(Parameter->getLocation(), diag::warn_unused_parameter)
12933 << Parameter->getDeclName();
12938 void Sema::DiagnoseSizeOfParametersAndReturnValue(
12939 ArrayRef<ParmVarDecl *> Parameters, QualType ReturnTy, NamedDecl *D) {
12940 if (LangOpts.NumLargeByValueCopy == 0) // No check.
12943 // Warn if the return value is pass-by-value and larger than the specified
12945 if (!ReturnTy->isDependentType() && ReturnTy.isPODType(Context)) {
12946 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity();
12947 if (Size > LangOpts.NumLargeByValueCopy)
12948 Diag(D->getLocation(), diag::warn_return_value_size)
12949 << D->getDeclName() << Size;
12952 // Warn if any parameter is pass-by-value and larger than the specified
12954 for (const ParmVarDecl *Parameter : Parameters) {
12955 QualType T = Parameter->getType();
12956 if (T->isDependentType() || !T.isPODType(Context))
12958 unsigned Size = Context.getTypeSizeInChars(T).getQuantity();
12959 if (Size > LangOpts.NumLargeByValueCopy)
12960 Diag(Parameter->getLocation(), diag::warn_parameter_size)
12961 << Parameter->getDeclName() << Size;
12965 ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc,
12966 SourceLocation NameLoc, IdentifierInfo *Name,
12967 QualType T, TypeSourceInfo *TSInfo,
12969 // In ARC, infer a lifetime qualifier for appropriate parameter types.
12970 if (getLangOpts().ObjCAutoRefCount &&
12971 T.getObjCLifetime() == Qualifiers::OCL_None &&
12972 T->isObjCLifetimeType()) {
12974 Qualifiers::ObjCLifetime lifetime;
12976 // Special cases for arrays:
12977 // - if it's const, use __unsafe_unretained
12978 // - otherwise, it's an error
12979 if (T->isArrayType()) {
12980 if (!T.isConstQualified()) {
12981 if (DelayedDiagnostics.shouldDelayDiagnostics())
12982 DelayedDiagnostics.add(
12983 sema::DelayedDiagnostic::makeForbiddenType(
12984 NameLoc, diag::err_arc_array_param_no_ownership, T, false));
12986 Diag(NameLoc, diag::err_arc_array_param_no_ownership)
12987 << TSInfo->getTypeLoc().getSourceRange();
12989 lifetime = Qualifiers::OCL_ExplicitNone;
12991 lifetime = T->getObjCARCImplicitLifetime();
12993 T = Context.getLifetimeQualifiedType(T, lifetime);
12996 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name,
12997 Context.getAdjustedParameterType(T),
12998 TSInfo, SC, nullptr);
13000 if (New->getType().hasNonTrivialToPrimitiveDestructCUnion() ||
13001 New->getType().hasNonTrivialToPrimitiveCopyCUnion())
13002 checkNonTrivialCUnion(New->getType(), New->getLocation(),
13003 NTCUC_FunctionParam, NTCUK_Destruct|NTCUK_Copy);
13005 // Parameters can not be abstract class types.
13006 // For record types, this is done by the AbstractClassUsageDiagnoser once
13007 // the class has been completely parsed.
13008 if (!CurContext->isRecord() &&
13009 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl,
13010 AbstractParamType))
13011 New->setInvalidDecl();
13013 // Parameter declarators cannot be interface types. All ObjC objects are
13014 // passed by reference.
13015 if (T->isObjCObjectType()) {
13016 SourceLocation TypeEndLoc =
13017 getLocForEndOfToken(TSInfo->getTypeLoc().getEndLoc());
13019 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T
13020 << FixItHint::CreateInsertion(TypeEndLoc, "*");
13021 T = Context.getObjCObjectPointerType(T);
13025 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
13026 // duration shall not be qualified by an address-space qualifier."
13027 // Since all parameters have automatic store duration, they can not have
13028 // an address space.
13029 if (T.getAddressSpace() != LangAS::Default &&
13030 // OpenCL allows function arguments declared to be an array of a type
13031 // to be qualified with an address space.
13032 !(getLangOpts().OpenCL &&
13033 (T->isArrayType() || T.getAddressSpace() == LangAS::opencl_private))) {
13034 Diag(NameLoc, diag::err_arg_with_address_space);
13035 New->setInvalidDecl();
13041 void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
13042 SourceLocation LocAfterDecls) {
13043 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
13045 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared'
13046 // for a K&R function.
13047 if (!FTI.hasPrototype) {
13048 for (int i = FTI.NumParams; i != 0; /* decrement in loop */) {
13050 if (FTI.Params[i].Param == nullptr) {
13051 SmallString<256> Code;
13052 llvm::raw_svector_ostream(Code)
13053 << " int " << FTI.Params[i].Ident->getName() << ";\n";
13054 Diag(FTI.Params[i].IdentLoc, diag::ext_param_not_declared)
13055 << FTI.Params[i].Ident
13056 << FixItHint::CreateInsertion(LocAfterDecls, Code);
13058 // Implicitly declare the argument as type 'int' for lack of a better
13060 AttributeFactory attrs;
13061 DeclSpec DS(attrs);
13062 const char* PrevSpec; // unused
13063 unsigned DiagID; // unused
13064 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.Params[i].IdentLoc, PrevSpec,
13065 DiagID, Context.getPrintingPolicy());
13066 // Use the identifier location for the type source range.
13067 DS.SetRangeStart(FTI.Params[i].IdentLoc);
13068 DS.SetRangeEnd(FTI.Params[i].IdentLoc);
13069 Declarator ParamD(DS, DeclaratorContext::KNRTypeListContext);
13070 ParamD.SetIdentifier(FTI.Params[i].Ident, FTI.Params[i].IdentLoc);
13071 FTI.Params[i].Param = ActOnParamDeclarator(S, ParamD);
13078 Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D,
13079 MultiTemplateParamsArg TemplateParameterLists,
13080 SkipBodyInfo *SkipBody) {
13081 assert(getCurFunctionDecl() == nullptr && "Function parsing confused");
13082 assert(D.isFunctionDeclarator() && "Not a function declarator!");
13083 Scope *ParentScope = FnBodyScope->getParent();
13085 D.setFunctionDefinitionKind(FDK_Definition);
13086 Decl *DP = HandleDeclarator(ParentScope, D, TemplateParameterLists);
13087 return ActOnStartOfFunctionDef(FnBodyScope, DP, SkipBody);
13090 void Sema::ActOnFinishInlineFunctionDef(FunctionDecl *D) {
13091 Consumer.HandleInlineFunctionDefinition(D);
13095 ShouldWarnAboutMissingPrototype(const FunctionDecl *FD,
13096 const FunctionDecl *&PossiblePrototype) {
13097 // Don't warn about invalid declarations.
13098 if (FD->isInvalidDecl())
13101 // Or declarations that aren't global.
13102 if (!FD->isGlobal())
13105 // Don't warn about C++ member functions.
13106 if (isa<CXXMethodDecl>(FD))
13109 // Don't warn about 'main'.
13113 // Don't warn about inline functions.
13114 if (FD->isInlined())
13117 // Don't warn about function templates.
13118 if (FD->getDescribedFunctionTemplate())
13121 // Don't warn about function template specializations.
13122 if (FD->isFunctionTemplateSpecialization())
13125 // Don't warn for OpenCL kernels.
13126 if (FD->hasAttr<OpenCLKernelAttr>())
13129 // Don't warn on explicitly deleted functions.
13130 if (FD->isDeleted())
13133 for (const FunctionDecl *Prev = FD->getPreviousDecl();
13134 Prev; Prev = Prev->getPreviousDecl()) {
13135 // Ignore any declarations that occur in function or method
13136 // scope, because they aren't visible from the header.
13137 if (Prev->getLexicalDeclContext()->isFunctionOrMethod())
13140 PossiblePrototype = Prev;
13141 return Prev->getType()->isFunctionNoProtoType();
13148 Sema::CheckForFunctionRedefinition(FunctionDecl *FD,
13149 const FunctionDecl *EffectiveDefinition,
13150 SkipBodyInfo *SkipBody) {
13151 const FunctionDecl *Definition = EffectiveDefinition;
13152 if (!Definition && !FD->isDefined(Definition) && !FD->isCXXClassMember()) {
13153 // If this is a friend function defined in a class template, it does not
13154 // have a body until it is used, nevertheless it is a definition, see
13157 // ... for the purpose of determining whether an instantiated redeclaration
13158 // is valid according to [basic.def.odr] and [class.mem], a declaration that
13159 // corresponds to a definition in the template is considered to be a
13162 // The following code must produce redefinition error:
13164 // template<typename T> struct C20 { friend void func_20() {} };
13166 // void func_20() {}
13168 for (auto I : FD->redecls()) {
13169 if (I != FD && !I->isInvalidDecl() &&
13170 I->getFriendObjectKind() != Decl::FOK_None) {
13171 if (FunctionDecl *Original = I->getInstantiatedFromMemberFunction()) {
13172 if (FunctionDecl *OrigFD = FD->getInstantiatedFromMemberFunction()) {
13173 // A merged copy of the same function, instantiated as a member of
13174 // the same class, is OK.
13175 if (declaresSameEntity(OrigFD, Original) &&
13176 declaresSameEntity(cast<Decl>(I->getLexicalDeclContext()),
13177 cast<Decl>(FD->getLexicalDeclContext())))
13181 if (Original->isThisDeclarationADefinition()) {
13191 // Similar to friend functions a friend function template may be a
13192 // definition and do not have a body if it is instantiated in a class
13194 if (FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate()) {
13195 for (auto I : FTD->redecls()) {
13196 auto D = cast<FunctionTemplateDecl>(I);
13198 assert(!D->isThisDeclarationADefinition() &&
13199 "More than one definition in redeclaration chain");
13200 if (D->getFriendObjectKind() != Decl::FOK_None)
13201 if (FunctionTemplateDecl *FT =
13202 D->getInstantiatedFromMemberTemplate()) {
13203 if (FT->isThisDeclarationADefinition()) {
13204 Definition = D->getTemplatedDecl();
13215 if (canRedefineFunction(Definition, getLangOpts()))
13218 // Don't emit an error when this is redefinition of a typo-corrected
13220 if (TypoCorrectedFunctionDefinitions.count(Definition))
13223 // If we don't have a visible definition of the function, and it's inline or
13224 // a template, skip the new definition.
13225 if (SkipBody && !hasVisibleDefinition(Definition) &&
13226 (Definition->getFormalLinkage() == InternalLinkage ||
13227 Definition->isInlined() ||
13228 Definition->getDescribedFunctionTemplate() ||
13229 Definition->getNumTemplateParameterLists())) {
13230 SkipBody->ShouldSkip = true;
13231 SkipBody->Previous = const_cast<FunctionDecl*>(Definition);
13232 if (auto *TD = Definition->getDescribedFunctionTemplate())
13233 makeMergedDefinitionVisible(TD);
13234 makeMergedDefinitionVisible(const_cast<FunctionDecl*>(Definition));
13238 if (getLangOpts().GNUMode && Definition->isInlineSpecified() &&
13239 Definition->getStorageClass() == SC_Extern)
13240 Diag(FD->getLocation(), diag::err_redefinition_extern_inline)
13241 << FD->getDeclName() << getLangOpts().CPlusPlus;
13243 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName();
13245 Diag(Definition->getLocation(), diag::note_previous_definition);
13246 FD->setInvalidDecl();
13249 static void RebuildLambdaScopeInfo(CXXMethodDecl *CallOperator,
13251 CXXRecordDecl *const LambdaClass = CallOperator->getParent();
13253 LambdaScopeInfo *LSI = S.PushLambdaScope();
13254 LSI->CallOperator = CallOperator;
13255 LSI->Lambda = LambdaClass;
13256 LSI->ReturnType = CallOperator->getReturnType();
13257 const LambdaCaptureDefault LCD = LambdaClass->getLambdaCaptureDefault();
13259 if (LCD == LCD_None)
13260 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_None;
13261 else if (LCD == LCD_ByCopy)
13262 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByval;
13263 else if (LCD == LCD_ByRef)
13264 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByref;
13265 DeclarationNameInfo DNI = CallOperator->getNameInfo();
13267 LSI->IntroducerRange = DNI.getCXXOperatorNameRange();
13268 LSI->Mutable = !CallOperator->isConst();
13270 // Add the captures to the LSI so they can be noted as already
13271 // captured within tryCaptureVar.
13272 auto I = LambdaClass->field_begin();
13273 for (const auto &C : LambdaClass->captures()) {
13274 if (C.capturesVariable()) {
13275 VarDecl *VD = C.getCapturedVar();
13276 if (VD->isInitCapture())
13277 S.CurrentInstantiationScope->InstantiatedLocal(VD, VD);
13278 QualType CaptureType = VD->getType();
13279 const bool ByRef = C.getCaptureKind() == LCK_ByRef;
13280 LSI->addCapture(VD, /*IsBlock*/false, ByRef,
13281 /*RefersToEnclosingVariableOrCapture*/true, C.getLocation(),
13282 /*EllipsisLoc*/C.isPackExpansion()
13283 ? C.getEllipsisLoc() : SourceLocation(),
13284 CaptureType, /*Invalid*/false);
13286 } else if (C.capturesThis()) {
13287 LSI->addThisCapture(/*Nested*/ false, C.getLocation(), I->getType(),
13288 C.getCaptureKind() == LCK_StarThis);
13290 LSI->addVLATypeCapture(C.getLocation(), I->getCapturedVLAType(),
13297 Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D,
13298 SkipBodyInfo *SkipBody) {
13300 // Parsing the function declaration failed in some way. Push on a fake scope
13301 // anyway so we can try to parse the function body.
13302 PushFunctionScope();
13303 PushExpressionEvaluationContext(ExprEvalContexts.back().Context);
13307 FunctionDecl *FD = nullptr;
13309 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D))
13310 FD = FunTmpl->getTemplatedDecl();
13312 FD = cast<FunctionDecl>(D);
13314 // Do not push if it is a lambda because one is already pushed when building
13315 // the lambda in ActOnStartOfLambdaDefinition().
13316 if (!isLambdaCallOperator(FD))
13317 PushExpressionEvaluationContext(ExprEvalContexts.back().Context);
13319 // Check for defining attributes before the check for redefinition.
13320 if (const auto *Attr = FD->getAttr<AliasAttr>()) {
13321 Diag(Attr->getLocation(), diag::err_alias_is_definition) << FD << 0;
13322 FD->dropAttr<AliasAttr>();
13323 FD->setInvalidDecl();
13325 if (const auto *Attr = FD->getAttr<IFuncAttr>()) {
13326 Diag(Attr->getLocation(), diag::err_alias_is_definition) << FD << 1;
13327 FD->dropAttr<IFuncAttr>();
13328 FD->setInvalidDecl();
13331 // See if this is a redefinition. If 'will have body' is already set, then
13332 // these checks were already performed when it was set.
13333 if (!FD->willHaveBody() && !FD->isLateTemplateParsed()) {
13334 CheckForFunctionRedefinition(FD, nullptr, SkipBody);
13336 // If we're skipping the body, we're done. Don't enter the scope.
13337 if (SkipBody && SkipBody->ShouldSkip)
13341 // Mark this function as "will have a body eventually". This lets users to
13342 // call e.g. isInlineDefinitionExternallyVisible while we're still parsing
13344 FD->setWillHaveBody();
13346 // If we are instantiating a generic lambda call operator, push
13347 // a LambdaScopeInfo onto the function stack. But use the information
13348 // that's already been calculated (ActOnLambdaExpr) to prime the current
13349 // LambdaScopeInfo.
13350 // When the template operator is being specialized, the LambdaScopeInfo,
13351 // has to be properly restored so that tryCaptureVariable doesn't try
13352 // and capture any new variables. In addition when calculating potential
13353 // captures during transformation of nested lambdas, it is necessary to
13354 // have the LSI properly restored.
13355 if (isGenericLambdaCallOperatorSpecialization(FD)) {
13356 assert(inTemplateInstantiation() &&
13357 "There should be an active template instantiation on the stack "
13358 "when instantiating a generic lambda!");
13359 RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this);
13361 // Enter a new function scope
13362 PushFunctionScope();
13365 // Builtin functions cannot be defined.
13366 if (unsigned BuiltinID = FD->getBuiltinID()) {
13367 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) &&
13368 !Context.BuiltinInfo.isPredefinedRuntimeFunction(BuiltinID)) {
13369 Diag(FD->getLocation(), diag::err_builtin_definition) << FD;
13370 FD->setInvalidDecl();
13374 // The return type of a function definition must be complete
13375 // (C99 6.9.1p3, C++ [dcl.fct]p6).
13376 QualType ResultType = FD->getReturnType();
13377 if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
13378 !FD->isInvalidDecl() &&
13379 RequireCompleteType(FD->getLocation(), ResultType,
13380 diag::err_func_def_incomplete_result))
13381 FD->setInvalidDecl();
13384 PushDeclContext(FnBodyScope, FD);
13386 // Check the validity of our function parameters
13387 CheckParmsForFunctionDef(FD->parameters(),
13388 /*CheckParameterNames=*/true);
13390 // Add non-parameter declarations already in the function to the current
13393 for (Decl *NPD : FD->decls()) {
13394 auto *NonParmDecl = dyn_cast<NamedDecl>(NPD);
13397 assert(!isa<ParmVarDecl>(NonParmDecl) &&
13398 "parameters should not be in newly created FD yet");
13400 // If the decl has a name, make it accessible in the current scope.
13401 if (NonParmDecl->getDeclName())
13402 PushOnScopeChains(NonParmDecl, FnBodyScope, /*AddToContext=*/false);
13404 // Similarly, dive into enums and fish their constants out, making them
13405 // accessible in this scope.
13406 if (auto *ED = dyn_cast<EnumDecl>(NonParmDecl)) {
13407 for (auto *EI : ED->enumerators())
13408 PushOnScopeChains(EI, FnBodyScope, /*AddToContext=*/false);
13413 // Introduce our parameters into the function scope
13414 for (auto Param : FD->parameters()) {
13415 Param->setOwningFunction(FD);
13417 // If this has an identifier, add it to the scope stack.
13418 if (Param->getIdentifier() && FnBodyScope) {
13419 CheckShadow(FnBodyScope, Param);
13421 PushOnScopeChains(Param, FnBodyScope);
13425 // Ensure that the function's exception specification is instantiated.
13426 if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>())
13427 ResolveExceptionSpec(D->getLocation(), FPT);
13429 // dllimport cannot be applied to non-inline function definitions.
13430 if (FD->hasAttr<DLLImportAttr>() && !FD->isInlined() &&
13431 !FD->isTemplateInstantiation()) {
13432 assert(!FD->hasAttr<DLLExportAttr>());
13433 Diag(FD->getLocation(), diag::err_attribute_dllimport_function_definition);
13434 FD->setInvalidDecl();
13437 // We want to attach documentation to original Decl (which might be
13438 // a function template).
13439 ActOnDocumentableDecl(D);
13440 if (getCurLexicalContext()->isObjCContainer() &&
13441 getCurLexicalContext()->getDeclKind() != Decl::ObjCCategoryImpl &&
13442 getCurLexicalContext()->getDeclKind() != Decl::ObjCImplementation)
13443 Diag(FD->getLocation(), diag::warn_function_def_in_objc_container);
13448 /// Given the set of return statements within a function body,
13449 /// compute the variables that are subject to the named return value
13452 /// Each of the variables that is subject to the named return value
13453 /// optimization will be marked as NRVO variables in the AST, and any
13454 /// return statement that has a marked NRVO variable as its NRVO candidate can
13455 /// use the named return value optimization.
13457 /// This function applies a very simplistic algorithm for NRVO: if every return
13458 /// statement in the scope of a variable has the same NRVO candidate, that
13459 /// candidate is an NRVO variable.
13460 void Sema::computeNRVO(Stmt *Body, FunctionScopeInfo *Scope) {
13461 ReturnStmt **Returns = Scope->Returns.data();
13463 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) {
13464 if (const VarDecl *NRVOCandidate = Returns[I]->getNRVOCandidate()) {
13465 if (!NRVOCandidate->isNRVOVariable())
13466 Returns[I]->setNRVOCandidate(nullptr);
13471 bool Sema::canDelayFunctionBody(const Declarator &D) {
13472 // We can't delay parsing the body of a constexpr function template (yet).
13473 if (D.getDeclSpec().hasConstexprSpecifier())
13476 // We can't delay parsing the body of a function template with a deduced
13477 // return type (yet).
13478 if (D.getDeclSpec().hasAutoTypeSpec()) {
13479 // If the placeholder introduces a non-deduced trailing return type,
13480 // we can still delay parsing it.
13481 if (D.getNumTypeObjects()) {
13482 const auto &Outer = D.getTypeObject(D.getNumTypeObjects() - 1);
13483 if (Outer.Kind == DeclaratorChunk::Function &&
13484 Outer.Fun.hasTrailingReturnType()) {
13485 QualType Ty = GetTypeFromParser(Outer.Fun.getTrailingReturnType());
13486 return Ty.isNull() || !Ty->isUndeducedType();
13495 bool Sema::canSkipFunctionBody(Decl *D) {
13496 // We cannot skip the body of a function (or function template) which is
13497 // constexpr, since we may need to evaluate its body in order to parse the
13498 // rest of the file.
13499 // We cannot skip the body of a function with an undeduced return type,
13500 // because any callers of that function need to know the type.
13501 if (const FunctionDecl *FD = D->getAsFunction()) {
13502 if (FD->isConstexpr())
13504 // We can't simply call Type::isUndeducedType here, because inside template
13505 // auto can be deduced to a dependent type, which is not considered
13507 if (FD->getReturnType()->getContainedDeducedType())
13510 return Consumer.shouldSkipFunctionBody(D);
13513 Decl *Sema::ActOnSkippedFunctionBody(Decl *Decl) {
13516 if (FunctionDecl *FD = Decl->getAsFunction())
13517 FD->setHasSkippedBody();
13518 else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(Decl))
13519 MD->setHasSkippedBody();
13523 Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) {
13524 return ActOnFinishFunctionBody(D, BodyArg, false);
13527 /// RAII object that pops an ExpressionEvaluationContext when exiting a function
13529 class ExitFunctionBodyRAII {
13531 ExitFunctionBodyRAII(Sema &S, bool IsLambda) : S(S), IsLambda(IsLambda) {}
13532 ~ExitFunctionBodyRAII() {
13534 S.PopExpressionEvaluationContext();
13539 bool IsLambda = false;
13542 static void diagnoseImplicitlyRetainedSelf(Sema &S) {
13543 llvm::DenseMap<const BlockDecl *, bool> EscapeInfo;
13545 auto IsOrNestedInEscapingBlock = [&](const BlockDecl *BD) {
13546 if (EscapeInfo.count(BD))
13547 return EscapeInfo[BD];
13550 const BlockDecl *CurBD = BD;
13553 R = !CurBD->doesNotEscape();
13556 CurBD = CurBD->getParent()->getInnermostBlockDecl();
13559 return EscapeInfo[BD] = R;
13562 // If the location where 'self' is implicitly retained is inside a escaping
13563 // block, emit a diagnostic.
13564 for (const std::pair<SourceLocation, const BlockDecl *> &P :
13565 S.ImplicitlyRetainedSelfLocs)
13566 if (IsOrNestedInEscapingBlock(P.second))
13567 S.Diag(P.first, diag::warn_implicitly_retains_self)
13568 << FixItHint::CreateInsertion(P.first, "self->");
13571 Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
13572 bool IsInstantiation) {
13573 FunctionDecl *FD = dcl ? dcl->getAsFunction() : nullptr;
13575 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
13576 sema::AnalysisBasedWarnings::Policy *ActivePolicy = nullptr;
13578 if (getLangOpts().Coroutines && getCurFunction()->isCoroutine())
13579 CheckCompletedCoroutineBody(FD, Body);
13581 // Do not call PopExpressionEvaluationContext() if it is a lambda because one
13582 // is already popped when finishing the lambda in BuildLambdaExpr(). This is
13583 // meant to pop the context added in ActOnStartOfFunctionDef().
13584 ExitFunctionBodyRAII ExitRAII(*this, isLambdaCallOperator(FD));
13588 FD->setWillHaveBody(false);
13590 if (getLangOpts().CPlusPlus14) {
13591 if (!FD->isInvalidDecl() && Body && !FD->isDependentContext() &&
13592 FD->getReturnType()->isUndeducedType()) {
13593 // If the function has a deduced result type but contains no 'return'
13594 // statements, the result type as written must be exactly 'auto', and
13595 // the deduced result type is 'void'.
13596 if (!FD->getReturnType()->getAs<AutoType>()) {
13597 Diag(dcl->getLocation(), diag::err_auto_fn_no_return_but_not_auto)
13598 << FD->getReturnType();
13599 FD->setInvalidDecl();
13601 // Substitute 'void' for the 'auto' in the type.
13602 TypeLoc ResultType = getReturnTypeLoc(FD);
13603 Context.adjustDeducedFunctionResultType(
13604 FD, SubstAutoType(ResultType.getType(), Context.VoidTy));
13607 } else if (getLangOpts().CPlusPlus11 && isLambdaCallOperator(FD)) {
13608 // In C++11, we don't use 'auto' deduction rules for lambda call
13609 // operators because we don't support return type deduction.
13610 auto *LSI = getCurLambda();
13611 if (LSI->HasImplicitReturnType) {
13612 deduceClosureReturnType(*LSI);
13614 // C++11 [expr.prim.lambda]p4:
13615 // [...] if there are no return statements in the compound-statement
13616 // [the deduced type is] the type void
13618 LSI->ReturnType.isNull() ? Context.VoidTy : LSI->ReturnType;
13620 // Update the return type to the deduced type.
13621 const FunctionProtoType *Proto =
13622 FD->getType()->getAs<FunctionProtoType>();
13623 FD->setType(Context.getFunctionType(RetType, Proto->getParamTypes(),
13624 Proto->getExtProtoInfo()));
13628 // If the function implicitly returns zero (like 'main') or is naked,
13629 // don't complain about missing return statements.
13630 if (FD->hasImplicitReturnZero() || FD->hasAttr<NakedAttr>())
13631 WP.disableCheckFallThrough();
13633 // MSVC permits the use of pure specifier (=0) on function definition,
13634 // defined at class scope, warn about this non-standard construct.
13635 if (getLangOpts().MicrosoftExt && FD->isPure() && !FD->isOutOfLine())
13636 Diag(FD->getLocation(), diag::ext_pure_function_definition);
13638 if (!FD->isInvalidDecl()) {
13639 // Don't diagnose unused parameters of defaulted or deleted functions.
13640 if (!FD->isDeleted() && !FD->isDefaulted() && !FD->hasSkippedBody())
13641 DiagnoseUnusedParameters(FD->parameters());
13642 DiagnoseSizeOfParametersAndReturnValue(FD->parameters(),
13643 FD->getReturnType(), FD);
13645 // If this is a structor, we need a vtable.
13646 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD))
13647 MarkVTableUsed(FD->getLocation(), Constructor->getParent());
13648 else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(FD))
13649 MarkVTableUsed(FD->getLocation(), Destructor->getParent());
13651 // Try to apply the named return value optimization. We have to check
13652 // if we can do this here because lambdas keep return statements around
13653 // to deduce an implicit return type.
13654 if (FD->getReturnType()->isRecordType() &&
13655 (!getLangOpts().CPlusPlus || !FD->isDependentContext()))
13656 computeNRVO(Body, getCurFunction());
13659 // GNU warning -Wmissing-prototypes:
13660 // Warn if a global function is defined without a previous
13661 // prototype declaration. This warning is issued even if the
13662 // definition itself provides a prototype. The aim is to detect
13663 // global functions that fail to be declared in header files.
13664 const FunctionDecl *PossiblePrototype = nullptr;
13665 if (ShouldWarnAboutMissingPrototype(FD, PossiblePrototype)) {
13666 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD;
13668 if (PossiblePrototype) {
13669 // We found a declaration that is not a prototype,
13670 // but that could be a zero-parameter prototype
13671 if (TypeSourceInfo *TI = PossiblePrototype->getTypeSourceInfo()) {
13672 TypeLoc TL = TI->getTypeLoc();
13673 if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>())
13674 Diag(PossiblePrototype->getLocation(),
13675 diag::note_declaration_not_a_prototype)
13676 << (FD->getNumParams() != 0)
13677 << (FD->getNumParams() == 0
13678 ? FixItHint::CreateInsertion(FTL.getRParenLoc(), "void")
13682 Diag(FD->getTypeSpecStartLoc(), diag::note_static_for_internal_linkage)
13683 << /* function */ 1
13684 << (FD->getStorageClass() == SC_None
13685 ? FixItHint::CreateInsertion(FD->getTypeSpecStartLoc(),
13690 // GNU warning -Wstrict-prototypes
13691 // Warn if K&R function is defined without a previous declaration.
13692 // This warning is issued only if the definition itself does not provide
13693 // a prototype. Only K&R definitions do not provide a prototype.
13694 // An empty list in a function declarator that is part of a definition
13695 // of that function specifies that the function has no parameters
13696 // (C99 6.7.5.3p14)
13697 if (!FD->hasWrittenPrototype() && FD->getNumParams() > 0 &&
13698 !LangOpts.CPlusPlus) {
13699 TypeSourceInfo *TI = FD->getTypeSourceInfo();
13700 TypeLoc TL = TI->getTypeLoc();
13701 FunctionTypeLoc FTL = TL.getAsAdjusted<FunctionTypeLoc>();
13702 Diag(FTL.getLParenLoc(), diag::warn_strict_prototypes) << 2;
13706 // Warn on CPUDispatch with an actual body.
13707 if (FD->isMultiVersion() && FD->hasAttr<CPUDispatchAttr>() && Body)
13708 if (const auto *CmpndBody = dyn_cast<CompoundStmt>(Body))
13709 if (!CmpndBody->body_empty())
13710 Diag(CmpndBody->body_front()->getBeginLoc(),
13711 diag::warn_dispatch_body_ignored);
13713 if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) {
13714 const CXXMethodDecl *KeyFunction;
13715 if (MD->isOutOfLine() && (MD = MD->getCanonicalDecl()) &&
13717 (KeyFunction = Context.getCurrentKeyFunction(MD->getParent())) &&
13718 MD == KeyFunction->getCanonicalDecl()) {
13719 // Update the key-function state if necessary for this ABI.
13720 if (FD->isInlined() &&
13721 !Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
13722 Context.setNonKeyFunction(MD);
13724 // If the newly-chosen key function is already defined, then we
13725 // need to mark the vtable as used retroactively.
13726 KeyFunction = Context.getCurrentKeyFunction(MD->getParent());
13727 const FunctionDecl *Definition;
13728 if (KeyFunction && KeyFunction->isDefined(Definition))
13729 MarkVTableUsed(Definition->getLocation(), MD->getParent(), true);
13731 // We just defined they key function; mark the vtable as used.
13732 MarkVTableUsed(FD->getLocation(), MD->getParent(), true);
13737 assert((FD == getCurFunctionDecl() || getCurLambda()->CallOperator == FD) &&
13738 "Function parsing confused");
13739 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) {
13740 assert(MD == getCurMethodDecl() && "Method parsing confused");
13742 if (!MD->isInvalidDecl()) {
13743 DiagnoseSizeOfParametersAndReturnValue(MD->parameters(),
13744 MD->getReturnType(), MD);
13747 computeNRVO(Body, getCurFunction());
13749 if (getCurFunction()->ObjCShouldCallSuper) {
13750 Diag(MD->getEndLoc(), diag::warn_objc_missing_super_call)
13751 << MD->getSelector().getAsString();
13752 getCurFunction()->ObjCShouldCallSuper = false;
13754 if (getCurFunction()->ObjCWarnForNoDesignatedInitChain) {
13755 const ObjCMethodDecl *InitMethod = nullptr;
13756 bool isDesignated =
13757 MD->isDesignatedInitializerForTheInterface(&InitMethod);
13758 assert(isDesignated && InitMethod);
13759 (void)isDesignated;
13761 auto superIsNSObject = [&](const ObjCMethodDecl *MD) {
13762 auto IFace = MD->getClassInterface();
13765 auto SuperD = IFace->getSuperClass();
13768 return SuperD->getIdentifier() ==
13769 NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject);
13771 // Don't issue this warning for unavailable inits or direct subclasses
13773 if (!MD->isUnavailable() && !superIsNSObject(MD)) {
13774 Diag(MD->getLocation(),
13775 diag::warn_objc_designated_init_missing_super_call);
13776 Diag(InitMethod->getLocation(),
13777 diag::note_objc_designated_init_marked_here);
13779 getCurFunction()->ObjCWarnForNoDesignatedInitChain = false;
13781 if (getCurFunction()->ObjCWarnForNoInitDelegation) {
13782 // Don't issue this warning for unavaialable inits.
13783 if (!MD->isUnavailable())
13784 Diag(MD->getLocation(),
13785 diag::warn_objc_secondary_init_missing_init_call);
13786 getCurFunction()->ObjCWarnForNoInitDelegation = false;
13789 diagnoseImplicitlyRetainedSelf(*this);
13791 // Parsing the function declaration failed in some way. Pop the fake scope
13793 PopFunctionScopeInfo(ActivePolicy, dcl);
13797 if (Body && getCurFunction()->HasPotentialAvailabilityViolations)
13798 DiagnoseUnguardedAvailabilityViolations(dcl);
13800 assert(!getCurFunction()->ObjCShouldCallSuper &&
13801 "This should only be set for ObjC methods, which should have been "
13802 "handled in the block above.");
13804 // Verify and clean out per-function state.
13805 if (Body && (!FD || !FD->isDefaulted())) {
13806 // C++ constructors that have function-try-blocks can't have return
13807 // statements in the handlers of that block. (C++ [except.handle]p14)
13809 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body))
13810 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body));
13812 // Verify that gotos and switch cases don't jump into scopes illegally.
13813 if (getCurFunction()->NeedsScopeChecking() &&
13814 !PP.isCodeCompletionEnabled())
13815 DiagnoseInvalidJumps(Body);
13817 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) {
13818 if (!Destructor->getParent()->isDependentType())
13819 CheckDestructor(Destructor);
13821 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
13822 Destructor->getParent());
13825 // If any errors have occurred, clear out any temporaries that may have
13826 // been leftover. This ensures that these temporaries won't be picked up for
13827 // deletion in some later function.
13828 if (getDiagnostics().hasErrorOccurred() ||
13829 getDiagnostics().getSuppressAllDiagnostics()) {
13830 DiscardCleanupsInEvaluationContext();
13832 if (!getDiagnostics().hasUncompilableErrorOccurred() &&
13833 !isa<FunctionTemplateDecl>(dcl)) {
13834 // Since the body is valid, issue any analysis-based warnings that are
13836 ActivePolicy = &WP;
13839 if (!IsInstantiation && FD && FD->isConstexpr() && !FD->isInvalidDecl() &&
13840 (!CheckConstexprFunctionDecl(FD) ||
13841 !CheckConstexprFunctionBody(FD, Body)))
13842 FD->setInvalidDecl();
13844 if (FD && FD->hasAttr<NakedAttr>()) {
13845 for (const Stmt *S : Body->children()) {
13846 // Allow local register variables without initializer as they don't
13847 // require prologue.
13848 bool RegisterVariables = false;
13849 if (auto *DS = dyn_cast<DeclStmt>(S)) {
13850 for (const auto *Decl : DS->decls()) {
13851 if (const auto *Var = dyn_cast<VarDecl>(Decl)) {
13852 RegisterVariables =
13853 Var->hasAttr<AsmLabelAttr>() && !Var->hasInit();
13854 if (!RegisterVariables)
13859 if (RegisterVariables)
13861 if (!isa<AsmStmt>(S) && !isa<NullStmt>(S)) {
13862 Diag(S->getBeginLoc(), diag::err_non_asm_stmt_in_naked_function);
13863 Diag(FD->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
13864 FD->setInvalidDecl();
13870 assert(ExprCleanupObjects.size() ==
13871 ExprEvalContexts.back().NumCleanupObjects &&
13872 "Leftover temporaries in function");
13873 assert(!Cleanup.exprNeedsCleanups() && "Unaccounted cleanups in function");
13874 assert(MaybeODRUseExprs.empty() &&
13875 "Leftover expressions for odr-use checking");
13878 if (!IsInstantiation)
13881 PopFunctionScopeInfo(ActivePolicy, dcl);
13882 // If any errors have occurred, clear out any temporaries that may have
13883 // been leftover. This ensures that these temporaries won't be picked up for
13884 // deletion in some later function.
13885 if (getDiagnostics().hasErrorOccurred()) {
13886 DiscardCleanupsInEvaluationContext();
13892 /// When we finish delayed parsing of an attribute, we must attach it to the
13894 void Sema::ActOnFinishDelayedAttribute(Scope *S, Decl *D,
13895 ParsedAttributes &Attrs) {
13896 // Always attach attributes to the underlying decl.
13897 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
13898 D = TD->getTemplatedDecl();
13899 ProcessDeclAttributeList(S, D, Attrs);
13901 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(D))
13902 if (Method->isStatic())
13903 checkThisInStaticMemberFunctionAttributes(Method);
13906 /// ImplicitlyDefineFunction - An undeclared identifier was used in a function
13907 /// call, forming a call to an implicitly defined function (per C99 6.5.1p2).
13908 NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
13909 IdentifierInfo &II, Scope *S) {
13910 // Find the scope in which the identifier is injected and the corresponding
13912 // FIXME: C89 does not say what happens if there is no enclosing block scope.
13913 // In that case, we inject the declaration into the translation unit scope
13915 Scope *BlockScope = S;
13916 while (!BlockScope->isCompoundStmtScope() && BlockScope->getParent())
13917 BlockScope = BlockScope->getParent();
13919 Scope *ContextScope = BlockScope;
13920 while (!ContextScope->getEntity())
13921 ContextScope = ContextScope->getParent();
13922 ContextRAII SavedContext(*this, ContextScope->getEntity());
13924 // Before we produce a declaration for an implicitly defined
13925 // function, see whether there was a locally-scoped declaration of
13926 // this name as a function or variable. If so, use that
13927 // (non-visible) declaration, and complain about it.
13928 NamedDecl *ExternCPrev = findLocallyScopedExternCDecl(&II);
13930 // We still need to inject the function into the enclosing block scope so
13931 // that later (non-call) uses can see it.
13932 PushOnScopeChains(ExternCPrev, BlockScope, /*AddToContext*/false);
13934 // C89 footnote 38:
13935 // If in fact it is not defined as having type "function returning int",
13936 // the behavior is undefined.
13937 if (!isa<FunctionDecl>(ExternCPrev) ||
13938 !Context.typesAreCompatible(
13939 cast<FunctionDecl>(ExternCPrev)->getType(),
13940 Context.getFunctionNoProtoType(Context.IntTy))) {
13941 Diag(Loc, diag::ext_use_out_of_scope_declaration)
13942 << ExternCPrev << !getLangOpts().C99;
13943 Diag(ExternCPrev->getLocation(), diag::note_previous_declaration);
13944 return ExternCPrev;
13948 // Extension in C99. Legal in C90, but warn about it.
13950 if (II.getName().startswith("__builtin_"))
13951 diag_id = diag::warn_builtin_unknown;
13952 // OpenCL v2.0 s6.9.u - Implicit function declaration is not supported.
13953 else if (getLangOpts().OpenCL)
13954 diag_id = diag::err_opencl_implicit_function_decl;
13955 else if (getLangOpts().C99)
13956 diag_id = diag::ext_implicit_function_decl;
13958 diag_id = diag::warn_implicit_function_decl;
13959 Diag(Loc, diag_id) << &II;
13961 // If we found a prior declaration of this function, don't bother building
13962 // another one. We've already pushed that one into scope, so there's nothing
13965 return ExternCPrev;
13967 // Because typo correction is expensive, only do it if the implicit
13968 // function declaration is going to be treated as an error.
13969 if (Diags.getDiagnosticLevel(diag_id, Loc) >= DiagnosticsEngine::Error) {
13970 TypoCorrection Corrected;
13971 DeclFilterCCC<FunctionDecl> CCC{};
13972 if (S && (Corrected =
13973 CorrectTypo(DeclarationNameInfo(&II, Loc), LookupOrdinaryName,
13974 S, nullptr, CCC, CTK_NonError)))
13975 diagnoseTypo(Corrected, PDiag(diag::note_function_suggestion),
13976 /*ErrorRecovery*/false);
13979 // Set a Declarator for the implicit definition: int foo();
13981 AttributeFactory attrFactory;
13982 DeclSpec DS(attrFactory);
13984 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID,
13985 Context.getPrintingPolicy());
13986 (void)Error; // Silence warning.
13987 assert(!Error && "Error setting up implicit decl!");
13988 SourceLocation NoLoc;
13989 Declarator D(DS, DeclaratorContext::BlockContext);
13990 D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false,
13991 /*IsAmbiguous=*/false,
13992 /*LParenLoc=*/NoLoc,
13993 /*Params=*/nullptr,
13995 /*EllipsisLoc=*/NoLoc,
13996 /*RParenLoc=*/NoLoc,
13997 /*RefQualifierIsLvalueRef=*/true,
13998 /*RefQualifierLoc=*/NoLoc,
13999 /*MutableLoc=*/NoLoc, EST_None,
14000 /*ESpecRange=*/SourceRange(),
14001 /*Exceptions=*/nullptr,
14002 /*ExceptionRanges=*/nullptr,
14003 /*NumExceptions=*/0,
14004 /*NoexceptExpr=*/nullptr,
14005 /*ExceptionSpecTokens=*/nullptr,
14006 /*DeclsInPrototype=*/None, Loc,
14008 std::move(DS.getAttributes()), SourceLocation());
14009 D.SetIdentifier(&II, Loc);
14011 // Insert this function into the enclosing block scope.
14012 FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(BlockScope, D));
14015 AddKnownFunctionAttributes(FD);
14020 /// Adds any function attributes that we know a priori based on
14021 /// the declaration of this function.
14023 /// These attributes can apply both to implicitly-declared builtins
14024 /// (like __builtin___printf_chk) or to library-declared functions
14025 /// like NSLog or printf.
14027 /// We need to check for duplicate attributes both here and where user-written
14028 /// attributes are applied to declarations.
14029 void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) {
14030 if (FD->isInvalidDecl())
14033 // If this is a built-in function, map its builtin attributes to
14034 // actual attributes.
14035 if (unsigned BuiltinID = FD->getBuiltinID()) {
14036 // Handle printf-formatting attributes.
14037 unsigned FormatIdx;
14039 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) {
14040 if (!FD->hasAttr<FormatAttr>()) {
14041 const char *fmt = "printf";
14042 unsigned int NumParams = FD->getNumParams();
14043 if (FormatIdx < NumParams && // NumParams may be 0 (e.g. vfprintf)
14044 FD->getParamDecl(FormatIdx)->getType()->isObjCObjectPointerType())
14046 FD->addAttr(FormatAttr::CreateImplicit(Context,
14047 &Context.Idents.get(fmt),
14049 HasVAListArg ? 0 : FormatIdx+2,
14050 FD->getLocation()));
14053 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx,
14055 if (!FD->hasAttr<FormatAttr>())
14056 FD->addAttr(FormatAttr::CreateImplicit(Context,
14057 &Context.Idents.get("scanf"),
14059 HasVAListArg ? 0 : FormatIdx+2,
14060 FD->getLocation()));
14063 // Handle automatically recognized callbacks.
14064 SmallVector<int, 4> Encoding;
14065 if (!FD->hasAttr<CallbackAttr>() &&
14066 Context.BuiltinInfo.performsCallback(BuiltinID, Encoding))
14067 FD->addAttr(CallbackAttr::CreateImplicit(
14068 Context, Encoding.data(), Encoding.size(), FD->getLocation()));
14070 // Mark const if we don't care about errno and that is the only thing
14071 // preventing the function from being const. This allows IRgen to use LLVM
14072 // intrinsics for such functions.
14073 if (!getLangOpts().MathErrno && !FD->hasAttr<ConstAttr>() &&
14074 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID))
14075 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
14077 // We make "fma" on some platforms const because we know it does not set
14078 // errno in those environments even though it could set errno based on the
14080 const llvm::Triple &Trip = Context.getTargetInfo().getTriple();
14081 if ((Trip.isGNUEnvironment() || Trip.isAndroid() || Trip.isOSMSVCRT()) &&
14082 !FD->hasAttr<ConstAttr>()) {
14083 switch (BuiltinID) {
14084 case Builtin::BI__builtin_fma:
14085 case Builtin::BI__builtin_fmaf:
14086 case Builtin::BI__builtin_fmal:
14087 case Builtin::BIfma:
14088 case Builtin::BIfmaf:
14089 case Builtin::BIfmal:
14090 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
14097 if (Context.BuiltinInfo.isReturnsTwice(BuiltinID) &&
14098 !FD->hasAttr<ReturnsTwiceAttr>())
14099 FD->addAttr(ReturnsTwiceAttr::CreateImplicit(Context,
14100 FD->getLocation()));
14101 if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->hasAttr<NoThrowAttr>())
14102 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
14103 if (Context.BuiltinInfo.isPure(BuiltinID) && !FD->hasAttr<PureAttr>())
14104 FD->addAttr(PureAttr::CreateImplicit(Context, FD->getLocation()));
14105 if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->hasAttr<ConstAttr>())
14106 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
14107 if (getLangOpts().CUDA && Context.BuiltinInfo.isTSBuiltin(BuiltinID) &&
14108 !FD->hasAttr<CUDADeviceAttr>() && !FD->hasAttr<CUDAHostAttr>()) {
14109 // Add the appropriate attribute, depending on the CUDA compilation mode
14110 // and which target the builtin belongs to. For example, during host
14111 // compilation, aux builtins are __device__, while the rest are __host__.
14112 if (getLangOpts().CUDAIsDevice !=
14113 Context.BuiltinInfo.isAuxBuiltinID(BuiltinID))
14114 FD->addAttr(CUDADeviceAttr::CreateImplicit(Context, FD->getLocation()));
14116 FD->addAttr(CUDAHostAttr::CreateImplicit(Context, FD->getLocation()));
14120 // If C++ exceptions are enabled but we are told extern "C" functions cannot
14121 // throw, add an implicit nothrow attribute to any extern "C" function we come
14123 if (getLangOpts().CXXExceptions && getLangOpts().ExternCNoUnwind &&
14124 FD->isExternC() && !FD->hasAttr<NoThrowAttr>()) {
14125 const auto *FPT = FD->getType()->getAs<FunctionProtoType>();
14126 if (!FPT || FPT->getExceptionSpecType() == EST_None)
14127 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
14130 IdentifierInfo *Name = FD->getIdentifier();
14133 if ((!getLangOpts().CPlusPlus &&
14134 FD->getDeclContext()->isTranslationUnit()) ||
14135 (isa<LinkageSpecDecl>(FD->getDeclContext()) &&
14136 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() ==
14137 LinkageSpecDecl::lang_c)) {
14138 // Okay: this could be a libc/libm/Objective-C function we know
14143 if (Name->isStr("asprintf") || Name->isStr("vasprintf")) {
14144 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be
14145 // target-specific builtins, perhaps?
14146 if (!FD->hasAttr<FormatAttr>())
14147 FD->addAttr(FormatAttr::CreateImplicit(Context,
14148 &Context.Idents.get("printf"), 2,
14149 Name->isStr("vasprintf") ? 0 : 3,
14150 FD->getLocation()));
14153 if (Name->isStr("__CFStringMakeConstantString")) {
14154 // We already have a __builtin___CFStringMakeConstantString,
14155 // but builds that use -fno-constant-cfstrings don't go through that.
14156 if (!FD->hasAttr<FormatArgAttr>())
14157 FD->addAttr(FormatArgAttr::CreateImplicit(Context, ParamIdx(1, FD),
14158 FD->getLocation()));
14162 TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
14163 TypeSourceInfo *TInfo) {
14164 assert(D.getIdentifier() && "Wrong callback for declspec without declarator");
14165 assert(!T.isNull() && "GetTypeForDeclarator() returned null type");
14168 assert(D.isInvalidType() && "no declarator info for valid type");
14169 TInfo = Context.getTrivialTypeSourceInfo(T);
14172 // Scope manipulation handled by caller.
14173 TypedefDecl *NewTD =
14174 TypedefDecl::Create(Context, CurContext, D.getBeginLoc(),
14175 D.getIdentifierLoc(), D.getIdentifier(), TInfo);
14177 // Bail out immediately if we have an invalid declaration.
14178 if (D.isInvalidType()) {
14179 NewTD->setInvalidDecl();
14183 if (D.getDeclSpec().isModulePrivateSpecified()) {
14184 if (CurContext->isFunctionOrMethod())
14185 Diag(NewTD->getLocation(), diag::err_module_private_local)
14186 << 2 << NewTD->getDeclName()
14187 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
14188 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
14190 NewTD->setModulePrivate();
14193 // C++ [dcl.typedef]p8:
14194 // If the typedef declaration defines an unnamed class (or
14195 // enum), the first typedef-name declared by the declaration
14196 // to be that class type (or enum type) is used to denote the
14197 // class type (or enum type) for linkage purposes only.
14198 // We need to check whether the type was declared in the declaration.
14199 switch (D.getDeclSpec().getTypeSpecType()) {
14202 case TST_interface:
14205 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
14206 setTagNameForLinkagePurposes(tagFromDeclSpec, NewTD);
14217 /// Check that this is a valid underlying type for an enum declaration.
14218 bool Sema::CheckEnumUnderlyingType(TypeSourceInfo *TI) {
14219 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
14220 QualType T = TI->getType();
14222 if (T->isDependentType())
14225 if (const BuiltinType *BT = T->getAs<BuiltinType>())
14226 if (BT->isInteger())
14229 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) << T;
14233 /// Check whether this is a valid redeclaration of a previous enumeration.
14234 /// \return true if the redeclaration was invalid.
14235 bool Sema::CheckEnumRedeclaration(SourceLocation EnumLoc, bool IsScoped,
14236 QualType EnumUnderlyingTy, bool IsFixed,
14237 const EnumDecl *Prev) {
14238 if (IsScoped != Prev->isScoped()) {
14239 Diag(EnumLoc, diag::err_enum_redeclare_scoped_mismatch)
14240 << Prev->isScoped();
14241 Diag(Prev->getLocation(), diag::note_previous_declaration);
14245 if (IsFixed && Prev->isFixed()) {
14246 if (!EnumUnderlyingTy->isDependentType() &&
14247 !Prev->getIntegerType()->isDependentType() &&
14248 !Context.hasSameUnqualifiedType(EnumUnderlyingTy,
14249 Prev->getIntegerType())) {
14250 // TODO: Highlight the underlying type of the redeclaration.
14251 Diag(EnumLoc, diag::err_enum_redeclare_type_mismatch)
14252 << EnumUnderlyingTy << Prev->getIntegerType();
14253 Diag(Prev->getLocation(), diag::note_previous_declaration)
14254 << Prev->getIntegerTypeRange();
14257 } else if (IsFixed != Prev->isFixed()) {
14258 Diag(EnumLoc, diag::err_enum_redeclare_fixed_mismatch)
14259 << Prev->isFixed();
14260 Diag(Prev->getLocation(), diag::note_previous_declaration);
14267 /// Get diagnostic %select index for tag kind for
14268 /// redeclaration diagnostic message.
14269 /// WARNING: Indexes apply to particular diagnostics only!
14271 /// \returns diagnostic %select index.
14272 static unsigned getRedeclDiagFromTagKind(TagTypeKind Tag) {
14274 case TTK_Struct: return 0;
14275 case TTK_Interface: return 1;
14276 case TTK_Class: return 2;
14277 default: llvm_unreachable("Invalid tag kind for redecl diagnostic!");
14281 /// Determine if tag kind is a class-key compatible with
14282 /// class for redeclaration (class, struct, or __interface).
14284 /// \returns true iff the tag kind is compatible.
14285 static bool isClassCompatTagKind(TagTypeKind Tag)
14287 return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface;
14290 Sema::NonTagKind Sema::getNonTagTypeDeclKind(const Decl *PrevDecl,
14292 if (isa<TypedefDecl>(PrevDecl))
14293 return NTK_Typedef;
14294 else if (isa<TypeAliasDecl>(PrevDecl))
14295 return NTK_TypeAlias;
14296 else if (isa<ClassTemplateDecl>(PrevDecl))
14297 return NTK_Template;
14298 else if (isa<TypeAliasTemplateDecl>(PrevDecl))
14299 return NTK_TypeAliasTemplate;
14300 else if (isa<TemplateTemplateParmDecl>(PrevDecl))
14301 return NTK_TemplateTemplateArgument;
14304 case TTK_Interface:
14306 return getLangOpts().CPlusPlus ? NTK_NonClass : NTK_NonStruct;
14308 return NTK_NonUnion;
14310 return NTK_NonEnum;
14312 llvm_unreachable("invalid TTK");
14315 /// Determine whether a tag with a given kind is acceptable
14316 /// as a redeclaration of the given tag declaration.
14318 /// \returns true if the new tag kind is acceptable, false otherwise.
14319 bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous,
14320 TagTypeKind NewTag, bool isDefinition,
14321 SourceLocation NewTagLoc,
14322 const IdentifierInfo *Name) {
14323 // C++ [dcl.type.elab]p3:
14324 // The class-key or enum keyword present in the
14325 // elaborated-type-specifier shall agree in kind with the
14326 // declaration to which the name in the elaborated-type-specifier
14327 // refers. This rule also applies to the form of
14328 // elaborated-type-specifier that declares a class-name or
14329 // friend class since it can be construed as referring to the
14330 // definition of the class. Thus, in any
14331 // elaborated-type-specifier, the enum keyword shall be used to
14332 // refer to an enumeration (7.2), the union class-key shall be
14333 // used to refer to a union (clause 9), and either the class or
14334 // struct class-key shall be used to refer to a class (clause 9)
14335 // declared using the class or struct class-key.
14336 TagTypeKind OldTag = Previous->getTagKind();
14337 if (OldTag != NewTag &&
14338 !(isClassCompatTagKind(OldTag) && isClassCompatTagKind(NewTag)))
14341 // Tags are compatible, but we might still want to warn on mismatched tags.
14342 // Non-class tags can't be mismatched at this point.
14343 if (!isClassCompatTagKind(NewTag))
14346 // Declarations for which -Wmismatched-tags is disabled are entirely ignored
14347 // by our warning analysis. We don't want to warn about mismatches with (eg)
14348 // declarations in system headers that are designed to be specialized, but if
14349 // a user asks us to warn, we should warn if their code contains mismatched
14351 auto IsIgnoredLoc = [&](SourceLocation Loc) {
14352 return getDiagnostics().isIgnored(diag::warn_struct_class_tag_mismatch,
14355 if (IsIgnoredLoc(NewTagLoc))
14358 auto IsIgnored = [&](const TagDecl *Tag) {
14359 return IsIgnoredLoc(Tag->getLocation());
14361 while (IsIgnored(Previous)) {
14362 Previous = Previous->getPreviousDecl();
14365 OldTag = Previous->getTagKind();
14368 bool isTemplate = false;
14369 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous))
14370 isTemplate = Record->getDescribedClassTemplate();
14372 if (inTemplateInstantiation()) {
14373 if (OldTag != NewTag) {
14374 // In a template instantiation, do not offer fix-its for tag mismatches
14375 // since they usually mess up the template instead of fixing the problem.
14376 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
14377 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
14378 << getRedeclDiagFromTagKind(OldTag);
14379 // FIXME: Note previous location?
14384 if (isDefinition) {
14385 // On definitions, check all previous tags and issue a fix-it for each
14386 // one that doesn't match the current tag.
14387 if (Previous->getDefinition()) {
14388 // Don't suggest fix-its for redefinitions.
14392 bool previousMismatch = false;
14393 for (const TagDecl *I : Previous->redecls()) {
14394 if (I->getTagKind() != NewTag) {
14395 // Ignore previous declarations for which the warning was disabled.
14399 if (!previousMismatch) {
14400 previousMismatch = true;
14401 Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch)
14402 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
14403 << getRedeclDiagFromTagKind(I->getTagKind());
14405 Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion)
14406 << getRedeclDiagFromTagKind(NewTag)
14407 << FixItHint::CreateReplacement(I->getInnerLocStart(),
14408 TypeWithKeyword::getTagTypeKindName(NewTag));
14414 // Identify the prevailing tag kind: this is the kind of the definition (if
14415 // there is a non-ignored definition), or otherwise the kind of the prior
14416 // (non-ignored) declaration.
14417 const TagDecl *PrevDef = Previous->getDefinition();
14418 if (PrevDef && IsIgnored(PrevDef))
14420 const TagDecl *Redecl = PrevDef ? PrevDef : Previous;
14421 if (Redecl->getTagKind() != NewTag) {
14422 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
14423 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
14424 << getRedeclDiagFromTagKind(OldTag);
14425 Diag(Redecl->getLocation(), diag::note_previous_use);
14427 // If there is a previous definition, suggest a fix-it.
14429 Diag(NewTagLoc, diag::note_struct_class_suggestion)
14430 << getRedeclDiagFromTagKind(Redecl->getTagKind())
14431 << FixItHint::CreateReplacement(SourceRange(NewTagLoc),
14432 TypeWithKeyword::getTagTypeKindName(Redecl->getTagKind()));
14439 /// Add a minimal nested name specifier fixit hint to allow lookup of a tag name
14440 /// from an outer enclosing namespace or file scope inside a friend declaration.
14441 /// This should provide the commented out code in the following snippet:
14445 /// struct Y { friend struct /*N::*/ X; };
14448 static FixItHint createFriendTagNNSFixIt(Sema &SemaRef, NamedDecl *ND, Scope *S,
14449 SourceLocation NameLoc) {
14450 // While the decl is in a namespace, do repeated lookup of that name and see
14451 // if we get the same namespace back. If we do not, continue until
14452 // translation unit scope, at which point we have a fully qualified NNS.
14453 SmallVector<IdentifierInfo *, 4> Namespaces;
14454 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
14455 for (; !DC->isTranslationUnit(); DC = DC->getParent()) {
14456 // This tag should be declared in a namespace, which can only be enclosed by
14457 // other namespaces. Bail if there's an anonymous namespace in the chain.
14458 NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(DC);
14459 if (!Namespace || Namespace->isAnonymousNamespace())
14460 return FixItHint();
14461 IdentifierInfo *II = Namespace->getIdentifier();
14462 Namespaces.push_back(II);
14463 NamedDecl *Lookup = SemaRef.LookupSingleName(
14464 S, II, NameLoc, Sema::LookupNestedNameSpecifierName);
14465 if (Lookup == Namespace)
14469 // Once we have all the namespaces, reverse them to go outermost first, and
14471 SmallString<64> Insertion;
14472 llvm::raw_svector_ostream OS(Insertion);
14473 if (DC->isTranslationUnit())
14475 std::reverse(Namespaces.begin(), Namespaces.end());
14476 for (auto *II : Namespaces)
14477 OS << II->getName() << "::";
14478 return FixItHint::CreateInsertion(NameLoc, Insertion);
14481 /// Determine whether a tag originally declared in context \p OldDC can
14482 /// be redeclared with an unqualified name in \p NewDC (assuming name lookup
14483 /// found a declaration in \p OldDC as a previous decl, perhaps through a
14484 /// using-declaration).
14485 static bool isAcceptableTagRedeclContext(Sema &S, DeclContext *OldDC,
14486 DeclContext *NewDC) {
14487 OldDC = OldDC->getRedeclContext();
14488 NewDC = NewDC->getRedeclContext();
14490 if (OldDC->Equals(NewDC))
14493 // In MSVC mode, we allow a redeclaration if the contexts are related (either
14494 // encloses the other).
14495 if (S.getLangOpts().MSVCCompat &&
14496 (OldDC->Encloses(NewDC) || NewDC->Encloses(OldDC)))
14502 /// This is invoked when we see 'struct foo' or 'struct {'. In the
14503 /// former case, Name will be non-null. In the later case, Name will be null.
14504 /// TagSpec indicates what kind of tag this is. TUK indicates whether this is a
14505 /// reference/declaration/definition of a tag.
14507 /// \param IsTypeSpecifier \c true if this is a type-specifier (or
14508 /// trailing-type-specifier) other than one in an alias-declaration.
14510 /// \param SkipBody If non-null, will be set to indicate if the caller should
14511 /// skip the definition of this tag and treat it as if it were a declaration.
14512 Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
14513 SourceLocation KWLoc, CXXScopeSpec &SS,
14514 IdentifierInfo *Name, SourceLocation NameLoc,
14515 const ParsedAttributesView &Attrs, AccessSpecifier AS,
14516 SourceLocation ModulePrivateLoc,
14517 MultiTemplateParamsArg TemplateParameterLists,
14518 bool &OwnedDecl, bool &IsDependent,
14519 SourceLocation ScopedEnumKWLoc,
14520 bool ScopedEnumUsesClassTag, TypeResult UnderlyingType,
14521 bool IsTypeSpecifier, bool IsTemplateParamOrArg,
14522 SkipBodyInfo *SkipBody) {
14523 // If this is not a definition, it must have a name.
14524 IdentifierInfo *OrigName = Name;
14525 assert((Name != nullptr || TUK == TUK_Definition) &&
14526 "Nameless record must be a definition!");
14527 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference);
14530 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
14531 bool ScopedEnum = ScopedEnumKWLoc.isValid();
14533 // FIXME: Check member specializations more carefully.
14534 bool isMemberSpecialization = false;
14535 bool Invalid = false;
14537 // We only need to do this matching if we have template parameters
14538 // or a scope specifier, which also conveniently avoids this work
14539 // for non-C++ cases.
14540 if (TemplateParameterLists.size() > 0 ||
14541 (SS.isNotEmpty() && TUK != TUK_Reference)) {
14542 if (TemplateParameterList *TemplateParams =
14543 MatchTemplateParametersToScopeSpecifier(
14544 KWLoc, NameLoc, SS, nullptr, TemplateParameterLists,
14545 TUK == TUK_Friend, isMemberSpecialization, Invalid)) {
14546 if (Kind == TTK_Enum) {
14547 Diag(KWLoc, diag::err_enum_template);
14551 if (TemplateParams->size() > 0) {
14552 // This is a declaration or definition of a class template (which may
14553 // be a member of another template).
14559 DeclResult Result = CheckClassTemplate(
14560 S, TagSpec, TUK, KWLoc, SS, Name, NameLoc, Attrs, TemplateParams,
14561 AS, ModulePrivateLoc,
14562 /*FriendLoc*/ SourceLocation(), TemplateParameterLists.size() - 1,
14563 TemplateParameterLists.data(), SkipBody);
14564 return Result.get();
14566 // The "template<>" header is extraneous.
14567 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
14568 << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
14569 isMemberSpecialization = true;
14574 // Figure out the underlying type if this a enum declaration. We need to do
14575 // this early, because it's needed to detect if this is an incompatible
14577 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying;
14578 bool IsFixed = !UnderlyingType.isUnset() || ScopedEnum;
14580 if (Kind == TTK_Enum) {
14581 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) {
14582 // No underlying type explicitly specified, or we failed to parse the
14583 // type, default to int.
14584 EnumUnderlying = Context.IntTy.getTypePtr();
14585 } else if (UnderlyingType.get()) {
14586 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
14587 // integral type; any cv-qualification is ignored.
14588 TypeSourceInfo *TI = nullptr;
14589 GetTypeFromParser(UnderlyingType.get(), &TI);
14590 EnumUnderlying = TI;
14592 if (CheckEnumUnderlyingType(TI))
14593 // Recover by falling back to int.
14594 EnumUnderlying = Context.IntTy.getTypePtr();
14596 if (DiagnoseUnexpandedParameterPack(TI->getTypeLoc().getBeginLoc(), TI,
14597 UPPC_FixedUnderlyingType))
14598 EnumUnderlying = Context.IntTy.getTypePtr();
14600 } else if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
14601 // For MSVC ABI compatibility, unfixed enums must use an underlying type
14602 // of 'int'. However, if this is an unfixed forward declaration, don't set
14603 // the underlying type unless the user enables -fms-compatibility. This
14604 // makes unfixed forward declared enums incomplete and is more conforming.
14605 if (TUK == TUK_Definition || getLangOpts().MSVCCompat)
14606 EnumUnderlying = Context.IntTy.getTypePtr();
14610 DeclContext *SearchDC = CurContext;
14611 DeclContext *DC = CurContext;
14612 bool isStdBadAlloc = false;
14613 bool isStdAlignValT = false;
14615 RedeclarationKind Redecl = forRedeclarationInCurContext();
14616 if (TUK == TUK_Friend || TUK == TUK_Reference)
14617 Redecl = NotForRedeclaration;
14619 /// Create a new tag decl in C/ObjC. Since the ODR-like semantics for ObjC/C
14620 /// implemented asks for structural equivalence checking, the returned decl
14621 /// here is passed back to the parser, allowing the tag body to be parsed.
14622 auto createTagFromNewDecl = [&]() -> TagDecl * {
14623 assert(!getLangOpts().CPlusPlus && "not meant for C++ usage");
14624 // If there is an identifier, use the location of the identifier as the
14625 // location of the decl, otherwise use the location of the struct/union
14627 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc;
14628 TagDecl *New = nullptr;
14630 if (Kind == TTK_Enum) {
14631 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name, nullptr,
14632 ScopedEnum, ScopedEnumUsesClassTag, IsFixed);
14633 // If this is an undefined enum, bail.
14634 if (TUK != TUK_Definition && !Invalid)
14636 if (EnumUnderlying) {
14637 EnumDecl *ED = cast<EnumDecl>(New);
14638 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo *>())
14639 ED->setIntegerTypeSourceInfo(TI);
14641 ED->setIntegerType(QualType(EnumUnderlying.get<const Type *>(), 0));
14642 ED->setPromotionType(ED->getIntegerType());
14644 } else { // struct/union
14645 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
14649 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) {
14650 // Add alignment attributes if necessary; these attributes are checked
14651 // when the ASTContext lays out the structure.
14653 // It is important for implementing the correct semantics that this
14654 // happen here (in ActOnTag). The #pragma pack stack is
14655 // maintained as a result of parser callbacks which can occur at
14656 // many points during the parsing of a struct declaration (because
14657 // the #pragma tokens are effectively skipped over during the
14658 // parsing of the struct).
14659 if (TUK == TUK_Definition && (!SkipBody || !SkipBody->ShouldSkip)) {
14660 AddAlignmentAttributesForRecord(RD);
14661 AddMsStructLayoutForRecord(RD);
14664 New->setLexicalDeclContext(CurContext);
14668 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl);
14669 if (Name && SS.isNotEmpty()) {
14670 // We have a nested-name tag ('struct foo::bar').
14672 // Check for invalid 'foo::'.
14673 if (SS.isInvalid()) {
14675 goto CreateNewDecl;
14678 // If this is a friend or a reference to a class in a dependent
14679 // context, don't try to make a decl for it.
14680 if (TUK == TUK_Friend || TUK == TUK_Reference) {
14681 DC = computeDeclContext(SS, false);
14683 IsDependent = true;
14687 DC = computeDeclContext(SS, true);
14689 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec)
14695 if (RequireCompleteDeclContext(SS, DC))
14699 // Look-up name inside 'foo::'.
14700 LookupQualifiedName(Previous, DC);
14702 if (Previous.isAmbiguous())
14705 if (Previous.empty()) {
14706 // Name lookup did not find anything. However, if the
14707 // nested-name-specifier refers to the current instantiation,
14708 // and that current instantiation has any dependent base
14709 // classes, we might find something at instantiation time: treat
14710 // this as a dependent elaborated-type-specifier.
14711 // But this only makes any sense for reference-like lookups.
14712 if (Previous.wasNotFoundInCurrentInstantiation() &&
14713 (TUK == TUK_Reference || TUK == TUK_Friend)) {
14714 IsDependent = true;
14718 // A tag 'foo::bar' must already exist.
14719 Diag(NameLoc, diag::err_not_tag_in_scope)
14720 << Kind << Name << DC << SS.getRange();
14723 goto CreateNewDecl;
14726 // C++14 [class.mem]p14:
14727 // If T is the name of a class, then each of the following shall have a
14728 // name different from T:
14729 // -- every member of class T that is itself a type
14730 if (TUK != TUK_Reference && TUK != TUK_Friend &&
14731 DiagnoseClassNameShadow(SearchDC, DeclarationNameInfo(Name, NameLoc)))
14734 // If this is a named struct, check to see if there was a previous forward
14735 // declaration or definition.
14736 // FIXME: We're looking into outer scopes here, even when we
14737 // shouldn't be. Doing so can result in ambiguities that we
14738 // shouldn't be diagnosing.
14739 LookupName(Previous, S);
14741 // When declaring or defining a tag, ignore ambiguities introduced
14742 // by types using'ed into this scope.
14743 if (Previous.isAmbiguous() &&
14744 (TUK == TUK_Definition || TUK == TUK_Declaration)) {
14745 LookupResult::Filter F = Previous.makeFilter();
14746 while (F.hasNext()) {
14747 NamedDecl *ND = F.next();
14748 if (!ND->getDeclContext()->getRedeclContext()->Equals(
14749 SearchDC->getRedeclContext()))
14755 // C++11 [namespace.memdef]p3:
14756 // If the name in a friend declaration is neither qualified nor
14757 // a template-id and the declaration is a function or an
14758 // elaborated-type-specifier, the lookup to determine whether
14759 // the entity has been previously declared shall not consider
14760 // any scopes outside the innermost enclosing namespace.
14762 // MSVC doesn't implement the above rule for types, so a friend tag
14763 // declaration may be a redeclaration of a type declared in an enclosing
14764 // scope. They do implement this rule for friend functions.
14766 // Does it matter that this should be by scope instead of by
14767 // semantic context?
14768 if (!Previous.empty() && TUK == TUK_Friend) {
14769 DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext();
14770 LookupResult::Filter F = Previous.makeFilter();
14771 bool FriendSawTagOutsideEnclosingNamespace = false;
14772 while (F.hasNext()) {
14773 NamedDecl *ND = F.next();
14774 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
14775 if (DC->isFileContext() &&
14776 !EnclosingNS->Encloses(ND->getDeclContext())) {
14777 if (getLangOpts().MSVCCompat)
14778 FriendSawTagOutsideEnclosingNamespace = true;
14785 // Diagnose this MSVC extension in the easy case where lookup would have
14786 // unambiguously found something outside the enclosing namespace.
14787 if (Previous.isSingleResult() && FriendSawTagOutsideEnclosingNamespace) {
14788 NamedDecl *ND = Previous.getFoundDecl();
14789 Diag(NameLoc, diag::ext_friend_tag_redecl_outside_namespace)
14790 << createFriendTagNNSFixIt(*this, ND, S, NameLoc);
14794 // Note: there used to be some attempt at recovery here.
14795 if (Previous.isAmbiguous())
14798 if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) {
14799 // FIXME: This makes sure that we ignore the contexts associated
14800 // with C structs, unions, and enums when looking for a matching
14801 // tag declaration or definition. See the similar lookup tweak
14802 // in Sema::LookupName; is there a better way to deal with this?
14803 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
14804 SearchDC = SearchDC->getParent();
14808 if (Previous.isSingleResult() &&
14809 Previous.getFoundDecl()->isTemplateParameter()) {
14810 // Maybe we will complain about the shadowed template parameter.
14811 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
14812 // Just pretend that we didn't see the previous declaration.
14816 if (getLangOpts().CPlusPlus && Name && DC && StdNamespace &&
14817 DC->Equals(getStdNamespace())) {
14818 if (Name->isStr("bad_alloc")) {
14819 // This is a declaration of or a reference to "std::bad_alloc".
14820 isStdBadAlloc = true;
14822 // If std::bad_alloc has been implicitly declared (but made invisible to
14823 // name lookup), fill in this implicit declaration as the previous
14824 // declaration, so that the declarations get chained appropriately.
14825 if (Previous.empty() && StdBadAlloc)
14826 Previous.addDecl(getStdBadAlloc());
14827 } else if (Name->isStr("align_val_t")) {
14828 isStdAlignValT = true;
14829 if (Previous.empty() && StdAlignValT)
14830 Previous.addDecl(getStdAlignValT());
14834 // If we didn't find a previous declaration, and this is a reference
14835 // (or friend reference), move to the correct scope. In C++, we
14836 // also need to do a redeclaration lookup there, just in case
14837 // there's a shadow friend decl.
14838 if (Name && Previous.empty() &&
14839 (TUK == TUK_Reference || TUK == TUK_Friend || IsTemplateParamOrArg)) {
14840 if (Invalid) goto CreateNewDecl;
14841 assert(SS.isEmpty());
14843 if (TUK == TUK_Reference || IsTemplateParamOrArg) {
14844 // C++ [basic.scope.pdecl]p5:
14845 // -- for an elaborated-type-specifier of the form
14847 // class-key identifier
14849 // if the elaborated-type-specifier is used in the
14850 // decl-specifier-seq or parameter-declaration-clause of a
14851 // function defined in namespace scope, the identifier is
14852 // declared as a class-name in the namespace that contains
14853 // the declaration; otherwise, except as a friend
14854 // declaration, the identifier is declared in the smallest
14855 // non-class, non-function-prototype scope that contains the
14858 // C99 6.7.2.3p8 has a similar (but not identical!) provision for
14859 // C structs and unions.
14861 // It is an error in C++ to declare (rather than define) an enum
14862 // type, including via an elaborated type specifier. We'll
14863 // diagnose that later; for now, declare the enum in the same
14864 // scope as we would have picked for any other tag type.
14866 // GNU C also supports this behavior as part of its incomplete
14867 // enum types extension, while GNU C++ does not.
14869 // Find the context where we'll be declaring the tag.
14870 // FIXME: We would like to maintain the current DeclContext as the
14871 // lexical context,
14872 SearchDC = getTagInjectionContext(SearchDC);
14874 // Find the scope where we'll be declaring the tag.
14875 S = getTagInjectionScope(S, getLangOpts());
14877 assert(TUK == TUK_Friend);
14878 // C++ [namespace.memdef]p3:
14879 // If a friend declaration in a non-local class first declares a
14880 // class or function, the friend class or function is a member of
14881 // the innermost enclosing namespace.
14882 SearchDC = SearchDC->getEnclosingNamespaceContext();
14885 // In C++, we need to do a redeclaration lookup to properly
14886 // diagnose some problems.
14887 // FIXME: redeclaration lookup is also used (with and without C++) to find a
14888 // hidden declaration so that we don't get ambiguity errors when using a
14889 // type declared by an elaborated-type-specifier. In C that is not correct
14890 // and we should instead merge compatible types found by lookup.
14891 if (getLangOpts().CPlusPlus) {
14892 Previous.setRedeclarationKind(forRedeclarationInCurContext());
14893 LookupQualifiedName(Previous, SearchDC);
14895 Previous.setRedeclarationKind(forRedeclarationInCurContext());
14896 LookupName(Previous, S);
14900 // If we have a known previous declaration to use, then use it.
14901 if (Previous.empty() && SkipBody && SkipBody->Previous)
14902 Previous.addDecl(SkipBody->Previous);
14904 if (!Previous.empty()) {
14905 NamedDecl *PrevDecl = Previous.getFoundDecl();
14906 NamedDecl *DirectPrevDecl = Previous.getRepresentativeDecl();
14908 // It's okay to have a tag decl in the same scope as a typedef
14909 // which hides a tag decl in the same scope. Finding this
14910 // insanity with a redeclaration lookup can only actually happen
14913 // This is also okay for elaborated-type-specifiers, which is
14914 // technically forbidden by the current standard but which is
14915 // okay according to the likely resolution of an open issue;
14916 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
14917 if (getLangOpts().CPlusPlus) {
14918 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
14919 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
14920 TagDecl *Tag = TT->getDecl();
14921 if (Tag->getDeclName() == Name &&
14922 Tag->getDeclContext()->getRedeclContext()
14923 ->Equals(TD->getDeclContext()->getRedeclContext())) {
14926 Previous.addDecl(Tag);
14927 Previous.resolveKind();
14933 // If this is a redeclaration of a using shadow declaration, it must
14934 // declare a tag in the same context. In MSVC mode, we allow a
14935 // redefinition if either context is within the other.
14936 if (auto *Shadow = dyn_cast<UsingShadowDecl>(DirectPrevDecl)) {
14937 auto *OldTag = dyn_cast<TagDecl>(PrevDecl);
14938 if (SS.isEmpty() && TUK != TUK_Reference && TUK != TUK_Friend &&
14939 isDeclInScope(Shadow, SearchDC, S, isMemberSpecialization) &&
14940 !(OldTag && isAcceptableTagRedeclContext(
14941 *this, OldTag->getDeclContext(), SearchDC))) {
14942 Diag(KWLoc, diag::err_using_decl_conflict_reverse);
14943 Diag(Shadow->getTargetDecl()->getLocation(),
14944 diag::note_using_decl_target);
14945 Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl)
14947 // Recover by ignoring the old declaration.
14949 goto CreateNewDecl;
14953 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
14954 // If this is a use of a previous tag, or if the tag is already declared
14955 // in the same scope (so that the definition/declaration completes or
14956 // rementions the tag), reuse the decl.
14957 if (TUK == TUK_Reference || TUK == TUK_Friend ||
14958 isDeclInScope(DirectPrevDecl, SearchDC, S,
14959 SS.isNotEmpty() || isMemberSpecialization)) {
14960 // Make sure that this wasn't declared as an enum and now used as a
14961 // struct or something similar.
14962 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind,
14963 TUK == TUK_Definition, KWLoc,
14965 bool SafeToContinue
14966 = (PrevTagDecl->getTagKind() != TTK_Enum &&
14968 if (SafeToContinue)
14969 Diag(KWLoc, diag::err_use_with_wrong_tag)
14971 << FixItHint::CreateReplacement(SourceRange(KWLoc),
14972 PrevTagDecl->getKindName());
14974 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
14975 Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
14977 if (SafeToContinue)
14978 Kind = PrevTagDecl->getTagKind();
14980 // Recover by making this an anonymous redefinition.
14987 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
14988 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);
14990 // If this is an elaborated-type-specifier for a scoped enumeration,
14991 // the 'class' keyword is not necessary and not permitted.
14992 if (TUK == TUK_Reference || TUK == TUK_Friend) {
14994 Diag(ScopedEnumKWLoc, diag::err_enum_class_reference)
14995 << PrevEnum->isScoped()
14996 << FixItHint::CreateRemoval(ScopedEnumKWLoc);
14997 return PrevTagDecl;
15000 QualType EnumUnderlyingTy;
15001 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
15002 EnumUnderlyingTy = TI->getType().getUnqualifiedType();
15003 else if (const Type *T = EnumUnderlying.dyn_cast<const Type*>())
15004 EnumUnderlyingTy = QualType(T, 0);
15006 // All conflicts with previous declarations are recovered by
15007 // returning the previous declaration, unless this is a definition,
15008 // in which case we want the caller to bail out.
15009 if (CheckEnumRedeclaration(NameLoc.isValid() ? NameLoc : KWLoc,
15010 ScopedEnum, EnumUnderlyingTy,
15011 IsFixed, PrevEnum))
15012 return TUK == TUK_Declaration ? PrevTagDecl : nullptr;
15015 // C++11 [class.mem]p1:
15016 // A member shall not be declared twice in the member-specification,
15017 // except that a nested class or member class template can be declared
15018 // and then later defined.
15019 if (TUK == TUK_Declaration && PrevDecl->isCXXClassMember() &&
15020 S->isDeclScope(PrevDecl)) {
15021 Diag(NameLoc, diag::ext_member_redeclared);
15022 Diag(PrevTagDecl->getLocation(), diag::note_previous_declaration);
15026 // If this is a use, just return the declaration we found, unless
15027 // we have attributes.
15028 if (TUK == TUK_Reference || TUK == TUK_Friend) {
15029 if (!Attrs.empty()) {
15030 // FIXME: Diagnose these attributes. For now, we create a new
15031 // declaration to hold them.
15032 } else if (TUK == TUK_Reference &&
15033 (PrevTagDecl->getFriendObjectKind() ==
15034 Decl::FOK_Undeclared ||
15035 PrevDecl->getOwningModule() != getCurrentModule()) &&
15037 // This declaration is a reference to an existing entity, but
15038 // has different visibility from that entity: it either makes
15039 // a friend visible or it makes a type visible in a new module.
15040 // In either case, create a new declaration. We only do this if
15041 // the declaration would have meant the same thing if no prior
15042 // declaration were found, that is, if it was found in the same
15043 // scope where we would have injected a declaration.
15044 if (!getTagInjectionContext(CurContext)->getRedeclContext()
15045 ->Equals(PrevDecl->getDeclContext()->getRedeclContext()))
15046 return PrevTagDecl;
15047 // This is in the injected scope, create a new declaration in
15049 S = getTagInjectionScope(S, getLangOpts());
15051 return PrevTagDecl;
15055 // Diagnose attempts to redefine a tag.
15056 if (TUK == TUK_Definition) {
15057 if (NamedDecl *Def = PrevTagDecl->getDefinition()) {
15058 // If we're defining a specialization and the previous definition
15059 // is from an implicit instantiation, don't emit an error
15060 // here; we'll catch this in the general case below.
15061 bool IsExplicitSpecializationAfterInstantiation = false;
15062 if (isMemberSpecialization) {
15063 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Def))
15064 IsExplicitSpecializationAfterInstantiation =
15065 RD->getTemplateSpecializationKind() !=
15066 TSK_ExplicitSpecialization;
15067 else if (EnumDecl *ED = dyn_cast<EnumDecl>(Def))
15068 IsExplicitSpecializationAfterInstantiation =
15069 ED->getTemplateSpecializationKind() !=
15070 TSK_ExplicitSpecialization;
15073 // Note that clang allows ODR-like semantics for ObjC/C, i.e., do
15074 // not keep more that one definition around (merge them). However,
15075 // ensure the decl passes the structural compatibility check in
15076 // C11 6.2.7/1 (or 6.1.2.6/1 in C89).
15077 NamedDecl *Hidden = nullptr;
15078 if (SkipBody && !hasVisibleDefinition(Def, &Hidden)) {
15079 // There is a definition of this tag, but it is not visible. We
15080 // explicitly make use of C++'s one definition rule here, and
15081 // assume that this definition is identical to the hidden one
15082 // we already have. Make the existing definition visible and
15083 // use it in place of this one.
15084 if (!getLangOpts().CPlusPlus) {
15085 // Postpone making the old definition visible until after we
15086 // complete parsing the new one and do the structural
15088 SkipBody->CheckSameAsPrevious = true;
15089 SkipBody->New = createTagFromNewDecl();
15090 SkipBody->Previous = Def;
15093 SkipBody->ShouldSkip = true;
15094 SkipBody->Previous = Def;
15095 makeMergedDefinitionVisible(Hidden);
15096 // Carry on and handle it like a normal definition. We'll
15097 // skip starting the definitiion later.
15099 } else if (!IsExplicitSpecializationAfterInstantiation) {
15100 // A redeclaration in function prototype scope in C isn't
15101 // visible elsewhere, so merely issue a warning.
15102 if (!getLangOpts().CPlusPlus && S->containedInPrototypeScope())
15103 Diag(NameLoc, diag::warn_redefinition_in_param_list) << Name;
15105 Diag(NameLoc, diag::err_redefinition) << Name;
15106 notePreviousDefinition(Def,
15107 NameLoc.isValid() ? NameLoc : KWLoc);
15108 // If this is a redefinition, recover by making this
15109 // struct be anonymous, which will make any later
15110 // references get the previous definition.
15116 // If the type is currently being defined, complain
15117 // about a nested redefinition.
15118 auto *TD = Context.getTagDeclType(PrevTagDecl)->getAsTagDecl();
15119 if (TD->isBeingDefined()) {
15120 Diag(NameLoc, diag::err_nested_redefinition) << Name;
15121 Diag(PrevTagDecl->getLocation(),
15122 diag::note_previous_definition);
15129 // Okay, this is definition of a previously declared or referenced
15130 // tag. We're going to create a new Decl for it.
15133 // Okay, we're going to make a redeclaration. If this is some kind
15134 // of reference, make sure we build the redeclaration in the same DC
15135 // as the original, and ignore the current access specifier.
15136 if (TUK == TUK_Friend || TUK == TUK_Reference) {
15137 SearchDC = PrevTagDecl->getDeclContext();
15141 // If we get here we have (another) forward declaration or we
15142 // have a definition. Just create a new decl.
15145 // If we get here, this is a definition of a new tag type in a nested
15146 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a
15147 // new decl/type. We set PrevDecl to NULL so that the entities
15148 // have distinct types.
15151 // If we get here, we're going to create a new Decl. If PrevDecl
15152 // is non-NULL, it's a definition of the tag declared by
15153 // PrevDecl. If it's NULL, we have a new definition.
15155 // Otherwise, PrevDecl is not a tag, but was found with tag
15156 // lookup. This is only actually possible in C++, where a few
15157 // things like templates still live in the tag namespace.
15159 // Use a better diagnostic if an elaborated-type-specifier
15160 // found the wrong kind of type on the first
15161 // (non-redeclaration) lookup.
15162 if ((TUK == TUK_Reference || TUK == TUK_Friend) &&
15163 !Previous.isForRedeclaration()) {
15164 NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl, Kind);
15165 Diag(NameLoc, diag::err_tag_reference_non_tag) << PrevDecl << NTK
15167 Diag(PrevDecl->getLocation(), diag::note_declared_at);
15170 // Otherwise, only diagnose if the declaration is in scope.
15171 } else if (!isDeclInScope(DirectPrevDecl, SearchDC, S,
15172 SS.isNotEmpty() || isMemberSpecialization)) {
15175 // Diagnose implicit declarations introduced by elaborated types.
15176 } else if (TUK == TUK_Reference || TUK == TUK_Friend) {
15177 NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl, Kind);
15178 Diag(NameLoc, diag::err_tag_reference_conflict) << NTK;
15179 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
15182 // Otherwise it's a declaration. Call out a particularly common
15184 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
15186 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
15187 Diag(NameLoc, diag::err_tag_definition_of_typedef)
15188 << Name << Kind << TND->getUnderlyingType();
15189 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
15192 // Otherwise, diagnose.
15194 // The tag name clashes with something else in the target scope,
15195 // issue an error and recover by making this tag be anonymous.
15196 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
15197 notePreviousDefinition(PrevDecl, NameLoc);
15202 // The existing declaration isn't relevant to us; we're in a
15203 // new scope, so clear out the previous declaration.
15210 TagDecl *PrevDecl = nullptr;
15211 if (Previous.isSingleResult())
15212 PrevDecl = cast<TagDecl>(Previous.getFoundDecl());
15214 // If there is an identifier, use the location of the identifier as the
15215 // location of the decl, otherwise use the location of the struct/union
15217 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc;
15219 // Otherwise, create a new declaration. If there is a previous
15220 // declaration of the same entity, the two will be linked via
15224 if (Kind == TTK_Enum) {
15225 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
15226 // enum X { A, B, C } D; D should chain to X.
15227 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name,
15228 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum,
15229 ScopedEnumUsesClassTag, IsFixed);
15231 if (isStdAlignValT && (!StdAlignValT || getStdAlignValT()->isImplicit()))
15232 StdAlignValT = cast<EnumDecl>(New);
15234 // If this is an undefined enum, warn.
15235 if (TUK != TUK_Definition && !Invalid) {
15237 if (IsFixed && cast<EnumDecl>(New)->isFixed()) {
15238 // C++0x: 7.2p2: opaque-enum-declaration.
15239 // Conflicts are diagnosed above. Do nothing.
15241 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) {
15242 Diag(Loc, diag::ext_forward_ref_enum_def)
15244 Diag(Def->getLocation(), diag::note_previous_definition);
15246 unsigned DiagID = diag::ext_forward_ref_enum;
15247 if (getLangOpts().MSVCCompat)
15248 DiagID = diag::ext_ms_forward_ref_enum;
15249 else if (getLangOpts().CPlusPlus)
15250 DiagID = diag::err_forward_ref_enum;
15255 if (EnumUnderlying) {
15256 EnumDecl *ED = cast<EnumDecl>(New);
15257 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
15258 ED->setIntegerTypeSourceInfo(TI);
15260 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
15261 ED->setPromotionType(ED->getIntegerType());
15262 assert(ED->isComplete() && "enum with type should be complete");
15265 // struct/union/class
15267 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
15268 // struct X { int A; } D; D should chain to X.
15269 if (getLangOpts().CPlusPlus) {
15270 // FIXME: Look for a way to use RecordDecl for simple structs.
15271 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
15272 cast_or_null<CXXRecordDecl>(PrevDecl));
15274 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit()))
15275 StdBadAlloc = cast<CXXRecordDecl>(New);
15277 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
15278 cast_or_null<RecordDecl>(PrevDecl));
15281 // C++11 [dcl.type]p3:
15282 // A type-specifier-seq shall not define a class or enumeration [...].
15283 if (getLangOpts().CPlusPlus && (IsTypeSpecifier || IsTemplateParamOrArg) &&
15284 TUK == TUK_Definition) {
15285 Diag(New->getLocation(), diag::err_type_defined_in_type_specifier)
15286 << Context.getTagDeclType(New);
15290 if (!Invalid && getLangOpts().CPlusPlus && TUK == TUK_Definition &&
15291 DC->getDeclKind() == Decl::Enum) {
15292 Diag(New->getLocation(), diag::err_type_defined_in_enum)
15293 << Context.getTagDeclType(New);
15297 // Maybe add qualifier info.
15298 if (SS.isNotEmpty()) {
15300 // If this is either a declaration or a definition, check the
15301 // nested-name-specifier against the current context.
15302 if ((TUK == TUK_Definition || TUK == TUK_Declaration) &&
15303 diagnoseQualifiedDeclaration(SS, DC, OrigName, Loc,
15304 isMemberSpecialization))
15307 New->setQualifierInfo(SS.getWithLocInContext(Context));
15308 if (TemplateParameterLists.size() > 0) {
15309 New->setTemplateParameterListsInfo(Context, TemplateParameterLists);
15316 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) {
15317 // Add alignment attributes if necessary; these attributes are checked when
15318 // the ASTContext lays out the structure.
15320 // It is important for implementing the correct semantics that this
15321 // happen here (in ActOnTag). The #pragma pack stack is
15322 // maintained as a result of parser callbacks which can occur at
15323 // many points during the parsing of a struct declaration (because
15324 // the #pragma tokens are effectively skipped over during the
15325 // parsing of the struct).
15326 if (TUK == TUK_Definition && (!SkipBody || !SkipBody->ShouldSkip)) {
15327 AddAlignmentAttributesForRecord(RD);
15328 AddMsStructLayoutForRecord(RD);
15332 if (ModulePrivateLoc.isValid()) {
15333 if (isMemberSpecialization)
15334 Diag(New->getLocation(), diag::err_module_private_specialization)
15336 << FixItHint::CreateRemoval(ModulePrivateLoc);
15337 // __module_private__ does not apply to local classes. However, we only
15338 // diagnose this as an error when the declaration specifiers are
15339 // freestanding. Here, we just ignore the __module_private__.
15340 else if (!SearchDC->isFunctionOrMethod())
15341 New->setModulePrivate();
15344 // If this is a specialization of a member class (of a class template),
15345 // check the specialization.
15346 if (isMemberSpecialization && CheckMemberSpecialization(New, Previous))
15349 // If we're declaring or defining a tag in function prototype scope in C,
15350 // note that this type can only be used within the function and add it to
15351 // the list of decls to inject into the function definition scope.
15352 if ((Name || Kind == TTK_Enum) &&
15353 getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
15354 if (getLangOpts().CPlusPlus) {
15355 // C++ [dcl.fct]p6:
15356 // Types shall not be defined in return or parameter types.
15357 if (TUK == TUK_Definition && !IsTypeSpecifier) {
15358 Diag(Loc, diag::err_type_defined_in_param_type)
15362 } else if (!PrevDecl) {
15363 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
15368 New->setInvalidDecl();
15370 // Set the lexical context. If the tag has a C++ scope specifier, the
15371 // lexical context will be different from the semantic context.
15372 New->setLexicalDeclContext(CurContext);
15374 // Mark this as a friend decl if applicable.
15375 // In Microsoft mode, a friend declaration also acts as a forward
15376 // declaration so we always pass true to setObjectOfFriendDecl to make
15377 // the tag name visible.
15378 if (TUK == TUK_Friend)
15379 New->setObjectOfFriendDecl(getLangOpts().MSVCCompat);
15381 // Set the access specifier.
15382 if (!Invalid && SearchDC->isRecord())
15383 SetMemberAccessSpecifier(New, PrevDecl, AS);
15386 CheckRedeclarationModuleOwnership(New, PrevDecl);
15388 if (TUK == TUK_Definition && (!SkipBody || !SkipBody->ShouldSkip))
15389 New->startDefinition();
15391 ProcessDeclAttributeList(S, New, Attrs);
15392 AddPragmaAttributes(S, New);
15394 // If this has an identifier, add it to the scope stack.
15395 if (TUK == TUK_Friend) {
15396 // We might be replacing an existing declaration in the lookup tables;
15397 // if so, borrow its access specifier.
15399 New->setAccess(PrevDecl->getAccess());
15401 DeclContext *DC = New->getDeclContext()->getRedeclContext();
15402 DC->makeDeclVisibleInContext(New);
15403 if (Name) // can be null along some error paths
15404 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
15405 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false);
15407 S = getNonFieldDeclScope(S);
15408 PushOnScopeChains(New, S, true);
15410 CurContext->addDecl(New);
15413 // If this is the C FILE type, notify the AST context.
15414 if (IdentifierInfo *II = New->getIdentifier())
15415 if (!New->isInvalidDecl() &&
15416 New->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
15418 Context.setFILEDecl(New);
15421 mergeDeclAttributes(New, PrevDecl);
15423 // If there's a #pragma GCC visibility in scope, set the visibility of this
15425 AddPushedVisibilityAttribute(New);
15427 if (isMemberSpecialization && !New->isInvalidDecl())
15428 CompleteMemberSpecialization(New, Previous);
15431 // In C++, don't return an invalid declaration. We can't recover well from
15432 // the cases where we make the type anonymous.
15433 if (Invalid && getLangOpts().CPlusPlus) {
15434 if (New->isBeingDefined())
15435 if (auto RD = dyn_cast<RecordDecl>(New))
15436 RD->completeDefinition();
15438 } else if (SkipBody && SkipBody->ShouldSkip) {
15439 return SkipBody->Previous;
15445 void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) {
15446 AdjustDeclIfTemplate(TagD);
15447 TagDecl *Tag = cast<TagDecl>(TagD);
15449 // Enter the tag context.
15450 PushDeclContext(S, Tag);
15452 ActOnDocumentableDecl(TagD);
15454 // If there's a #pragma GCC visibility in scope, set the visibility of this
15456 AddPushedVisibilityAttribute(Tag);
15459 bool Sema::ActOnDuplicateDefinition(DeclSpec &DS, Decl *Prev,
15460 SkipBodyInfo &SkipBody) {
15461 if (!hasStructuralCompatLayout(Prev, SkipBody.New))
15464 // Make the previous decl visible.
15465 makeMergedDefinitionVisible(SkipBody.Previous);
15469 Decl *Sema::ActOnObjCContainerStartDefinition(Decl *IDecl) {
15470 assert(isa<ObjCContainerDecl>(IDecl) &&
15471 "ActOnObjCContainerStartDefinition - Not ObjCContainerDecl");
15472 DeclContext *OCD = cast<DeclContext>(IDecl);
15473 assert(getContainingDC(OCD) == CurContext &&
15474 "The next DeclContext should be lexically contained in the current one.");
15479 void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD,
15480 SourceLocation FinalLoc,
15481 bool IsFinalSpelledSealed,
15482 SourceLocation LBraceLoc) {
15483 AdjustDeclIfTemplate(TagD);
15484 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD);
15486 FieldCollector->StartClass();
15488 if (!Record->getIdentifier())
15491 if (FinalLoc.isValid())
15492 Record->addAttr(new (Context)
15493 FinalAttr(FinalLoc, Context, IsFinalSpelledSealed));
15496 // [...] The class-name is also inserted into the scope of the
15497 // class itself; this is known as the injected-class-name. For
15498 // purposes of access checking, the injected-class-name is treated
15499 // as if it were a public member name.
15500 CXXRecordDecl *InjectedClassName = CXXRecordDecl::Create(
15501 Context, Record->getTagKind(), CurContext, Record->getBeginLoc(),
15502 Record->getLocation(), Record->getIdentifier(),
15503 /*PrevDecl=*/nullptr,
15504 /*DelayTypeCreation=*/true);
15505 Context.getTypeDeclType(InjectedClassName, Record);
15506 InjectedClassName->setImplicit();
15507 InjectedClassName->setAccess(AS_public);
15508 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate())
15509 InjectedClassName->setDescribedClassTemplate(Template);
15510 PushOnScopeChains(InjectedClassName, S);
15511 assert(InjectedClassName->isInjectedClassName() &&
15512 "Broken injected-class-name");
15515 void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD,
15516 SourceRange BraceRange) {
15517 AdjustDeclIfTemplate(TagD);
15518 TagDecl *Tag = cast<TagDecl>(TagD);
15519 Tag->setBraceRange(BraceRange);
15521 // Make sure we "complete" the definition even it is invalid.
15522 if (Tag->isBeingDefined()) {
15523 assert(Tag->isInvalidDecl() && "We should already have completed it");
15524 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
15525 RD->completeDefinition();
15528 if (isa<CXXRecordDecl>(Tag)) {
15529 FieldCollector->FinishClass();
15532 // Exit this scope of this tag's definition.
15535 if (getCurLexicalContext()->isObjCContainer() &&
15536 Tag->getDeclContext()->isFileContext())
15537 Tag->setTopLevelDeclInObjCContainer();
15539 // Notify the consumer that we've defined a tag.
15540 if (!Tag->isInvalidDecl())
15541 Consumer.HandleTagDeclDefinition(Tag);
15544 void Sema::ActOnObjCContainerFinishDefinition() {
15545 // Exit this scope of this interface definition.
15549 void Sema::ActOnObjCTemporaryExitContainerContext(DeclContext *DC) {
15550 assert(DC == CurContext && "Mismatch of container contexts");
15551 OriginalLexicalContext = DC;
15552 ActOnObjCContainerFinishDefinition();
15555 void Sema::ActOnObjCReenterContainerContext(DeclContext *DC) {
15556 ActOnObjCContainerStartDefinition(cast<Decl>(DC));
15557 OriginalLexicalContext = nullptr;
15560 void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) {
15561 AdjustDeclIfTemplate(TagD);
15562 TagDecl *Tag = cast<TagDecl>(TagD);
15563 Tag->setInvalidDecl();
15565 // Make sure we "complete" the definition even it is invalid.
15566 if (Tag->isBeingDefined()) {
15567 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
15568 RD->completeDefinition();
15571 // We're undoing ActOnTagStartDefinition here, not
15572 // ActOnStartCXXMemberDeclarations, so we don't have to mess with
15573 // the FieldCollector.
15578 // Note that FieldName may be null for anonymous bitfields.
15579 ExprResult Sema::VerifyBitField(SourceLocation FieldLoc,
15580 IdentifierInfo *FieldName,
15581 QualType FieldTy, bool IsMsStruct,
15582 Expr *BitWidth, bool *ZeroWidth) {
15583 // Default to true; that shouldn't confuse checks for emptiness
15587 // C99 6.7.2.1p4 - verify the field type.
15588 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
15589 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) {
15590 // Handle incomplete types with specific error.
15591 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete))
15592 return ExprError();
15594 return Diag(FieldLoc, diag::err_not_integral_type_bitfield)
15595 << FieldName << FieldTy << BitWidth->getSourceRange();
15596 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield)
15597 << FieldTy << BitWidth->getSourceRange();
15598 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth),
15599 UPPC_BitFieldWidth))
15600 return ExprError();
15602 // If the bit-width is type- or value-dependent, don't try to check
15604 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent())
15607 llvm::APSInt Value;
15608 ExprResult ICE = VerifyIntegerConstantExpression(BitWidth, &Value);
15609 if (ICE.isInvalid())
15611 BitWidth = ICE.get();
15613 if (Value != 0 && ZeroWidth)
15614 *ZeroWidth = false;
15616 // Zero-width bitfield is ok for anonymous field.
15617 if (Value == 0 && FieldName)
15618 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName;
15620 if (Value.isSigned() && Value.isNegative()) {
15622 return Diag(FieldLoc, diag::err_bitfield_has_negative_width)
15623 << FieldName << Value.toString(10);
15624 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width)
15625 << Value.toString(10);
15628 if (!FieldTy->isDependentType()) {
15629 uint64_t TypeStorageSize = Context.getTypeSize(FieldTy);
15630 uint64_t TypeWidth = Context.getIntWidth(FieldTy);
15631 bool BitfieldIsOverwide = Value.ugt(TypeWidth);
15633 // Over-wide bitfields are an error in C or when using the MSVC bitfield
15635 bool CStdConstraintViolation =
15636 BitfieldIsOverwide && !getLangOpts().CPlusPlus;
15637 bool MSBitfieldViolation =
15638 Value.ugt(TypeStorageSize) &&
15639 (IsMsStruct || Context.getTargetInfo().getCXXABI().isMicrosoft());
15640 if (CStdConstraintViolation || MSBitfieldViolation) {
15641 unsigned DiagWidth =
15642 CStdConstraintViolation ? TypeWidth : TypeStorageSize;
15644 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_width)
15645 << FieldName << (unsigned)Value.getZExtValue()
15646 << !CStdConstraintViolation << DiagWidth;
15648 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_width)
15649 << (unsigned)Value.getZExtValue() << !CStdConstraintViolation
15653 // Warn on types where the user might conceivably expect to get all
15654 // specified bits as value bits: that's all integral types other than
15656 if (BitfieldIsOverwide && !FieldTy->isBooleanType()) {
15658 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_width)
15659 << FieldName << (unsigned)Value.getZExtValue()
15660 << (unsigned)TypeWidth;
15662 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_width)
15663 << (unsigned)Value.getZExtValue() << (unsigned)TypeWidth;
15670 /// ActOnField - Each field of a C struct/union is passed into this in order
15671 /// to create a FieldDecl object for it.
15672 Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
15673 Declarator &D, Expr *BitfieldWidth) {
15674 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD),
15675 DeclStart, D, static_cast<Expr*>(BitfieldWidth),
15676 /*InitStyle=*/ICIS_NoInit, AS_public);
15680 /// HandleField - Analyze a field of a C struct or a C++ data member.
15682 FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
15683 SourceLocation DeclStart,
15684 Declarator &D, Expr *BitWidth,
15685 InClassInitStyle InitStyle,
15686 AccessSpecifier AS) {
15687 if (D.isDecompositionDeclarator()) {
15688 const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
15689 Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
15690 << Decomp.getSourceRange();
15694 IdentifierInfo *II = D.getIdentifier();
15695 SourceLocation Loc = DeclStart;
15696 if (II) Loc = D.getIdentifierLoc();
15698 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
15699 QualType T = TInfo->getType();
15700 if (getLangOpts().CPlusPlus) {
15701 CheckExtraCXXDefaultArguments(D);
15703 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
15704 UPPC_DataMemberType)) {
15705 D.setInvalidType();
15707 TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
15711 DiagnoseFunctionSpecifiers(D.getDeclSpec());
15713 if (D.getDeclSpec().isInlineSpecified())
15714 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
15715 << getLangOpts().CPlusPlus17;
15716 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
15717 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
15718 diag::err_invalid_thread)
15719 << DeclSpec::getSpecifierName(TSCS);
15721 // Check to see if this name was declared as a member previously
15722 NamedDecl *PrevDecl = nullptr;
15723 LookupResult Previous(*this, II, Loc, LookupMemberName,
15724 ForVisibleRedeclaration);
15725 LookupName(Previous, S);
15726 switch (Previous.getResultKind()) {
15727 case LookupResult::Found:
15728 case LookupResult::FoundUnresolvedValue:
15729 PrevDecl = Previous.getAsSingle<NamedDecl>();
15732 case LookupResult::FoundOverloaded:
15733 PrevDecl = Previous.getRepresentativeDecl();
15736 case LookupResult::NotFound:
15737 case LookupResult::NotFoundInCurrentInstantiation:
15738 case LookupResult::Ambiguous:
15741 Previous.suppressDiagnostics();
15743 if (PrevDecl && PrevDecl->isTemplateParameter()) {
15744 // Maybe we will complain about the shadowed template parameter.
15745 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
15746 // Just pretend that we didn't see the previous declaration.
15747 PrevDecl = nullptr;
15750 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
15751 PrevDecl = nullptr;
15754 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable);
15755 SourceLocation TSSL = D.getBeginLoc();
15757 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, InitStyle,
15758 TSSL, AS, PrevDecl, &D);
15760 if (NewFD->isInvalidDecl())
15761 Record->setInvalidDecl();
15763 if (D.getDeclSpec().isModulePrivateSpecified())
15764 NewFD->setModulePrivate();
15766 if (NewFD->isInvalidDecl() && PrevDecl) {
15767 // Don't introduce NewFD into scope; there's already something
15768 // with the same name in the same scope.
15770 PushOnScopeChains(NewFD, S);
15772 Record->addDecl(NewFD);
15777 /// Build a new FieldDecl and check its well-formedness.
15779 /// This routine builds a new FieldDecl given the fields name, type,
15780 /// record, etc. \p PrevDecl should refer to any previous declaration
15781 /// with the same name and in the same scope as the field to be
15784 /// \returns a new FieldDecl.
15786 /// \todo The Declarator argument is a hack. It will be removed once
15787 FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T,
15788 TypeSourceInfo *TInfo,
15789 RecordDecl *Record, SourceLocation Loc,
15790 bool Mutable, Expr *BitWidth,
15791 InClassInitStyle InitStyle,
15792 SourceLocation TSSL,
15793 AccessSpecifier AS, NamedDecl *PrevDecl,
15795 IdentifierInfo *II = Name.getAsIdentifierInfo();
15796 bool InvalidDecl = false;
15797 if (D) InvalidDecl = D->isInvalidType();
15799 // If we receive a broken type, recover by assuming 'int' and
15800 // marking this declaration as invalid.
15802 InvalidDecl = true;
15806 QualType EltTy = Context.getBaseElementType(T);
15807 if (!EltTy->isDependentType()) {
15808 if (RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) {
15809 // Fields of incomplete type force their record to be invalid.
15810 Record->setInvalidDecl();
15811 InvalidDecl = true;
15814 EltTy->isIncompleteType(&Def);
15815 if (Def && Def->isInvalidDecl()) {
15816 Record->setInvalidDecl();
15817 InvalidDecl = true;
15822 // TR 18037 does not allow fields to be declared with address space
15823 if (T.getQualifiers().hasAddressSpace() || T->isDependentAddressSpaceType() ||
15824 T->getBaseElementTypeUnsafe()->isDependentAddressSpaceType()) {
15825 Diag(Loc, diag::err_field_with_address_space);
15826 Record->setInvalidDecl();
15827 InvalidDecl = true;
15830 if (LangOpts.OpenCL) {
15831 // OpenCL v1.2 s6.9b,r & OpenCL v2.0 s6.12.5 - The following types cannot be
15832 // used as structure or union field: image, sampler, event or block types.
15833 if (T->isEventT() || T->isImageType() || T->isSamplerT() ||
15834 T->isBlockPointerType()) {
15835 Diag(Loc, diag::err_opencl_type_struct_or_union_field) << T;
15836 Record->setInvalidDecl();
15837 InvalidDecl = true;
15839 // OpenCL v1.2 s6.9.c: bitfields are not supported.
15841 Diag(Loc, diag::err_opencl_bitfields);
15842 InvalidDecl = true;
15846 // Anonymous bit-fields cannot be cv-qualified (CWG 2229).
15847 if (!InvalidDecl && getLangOpts().CPlusPlus && !II && BitWidth &&
15848 T.hasQualifiers()) {
15849 InvalidDecl = true;
15850 Diag(Loc, diag::err_anon_bitfield_qualifiers);
15853 // C99 6.7.2.1p8: A member of a structure or union may have any type other
15854 // than a variably modified type.
15855 if (!InvalidDecl && T->isVariablyModifiedType()) {
15856 bool SizeIsNegative;
15857 llvm::APSInt Oversized;
15859 TypeSourceInfo *FixedTInfo =
15860 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
15864 Diag(Loc, diag::warn_illegal_constant_array_size);
15865 TInfo = FixedTInfo;
15866 T = FixedTInfo->getType();
15868 if (SizeIsNegative)
15869 Diag(Loc, diag::err_typecheck_negative_array_size);
15870 else if (Oversized.getBoolValue())
15871 Diag(Loc, diag::err_array_too_large)
15872 << Oversized.toString(10);
15874 Diag(Loc, diag::err_typecheck_field_variable_size);
15875 InvalidDecl = true;
15879 // Fields can not have abstract class types
15880 if (!InvalidDecl && RequireNonAbstractType(Loc, T,
15881 diag::err_abstract_type_in_decl,
15882 AbstractFieldType))
15883 InvalidDecl = true;
15885 bool ZeroWidth = false;
15887 BitWidth = nullptr;
15888 // If this is declared as a bit-field, check the bit-field.
15890 BitWidth = VerifyBitField(Loc, II, T, Record->isMsStruct(Context), BitWidth,
15893 InvalidDecl = true;
15894 BitWidth = nullptr;
15899 // Check that 'mutable' is consistent with the type of the declaration.
15900 if (!InvalidDecl && Mutable) {
15901 unsigned DiagID = 0;
15902 if (T->isReferenceType())
15903 DiagID = getLangOpts().MSVCCompat ? diag::ext_mutable_reference
15904 : diag::err_mutable_reference;
15905 else if (T.isConstQualified())
15906 DiagID = diag::err_mutable_const;
15909 SourceLocation ErrLoc = Loc;
15910 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid())
15911 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc();
15912 Diag(ErrLoc, DiagID);
15913 if (DiagID != diag::ext_mutable_reference) {
15915 InvalidDecl = true;
15920 // C++11 [class.union]p8 (DR1460):
15921 // At most one variant member of a union may have a
15922 // brace-or-equal-initializer.
15923 if (InitStyle != ICIS_NoInit)
15924 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Record), Loc);
15926 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo,
15927 BitWidth, Mutable, InitStyle);
15929 NewFD->setInvalidDecl();
15931 if (PrevDecl && !isa<TagDecl>(PrevDecl)) {
15932 Diag(Loc, diag::err_duplicate_member) << II;
15933 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
15934 NewFD->setInvalidDecl();
15937 if (!InvalidDecl && getLangOpts().CPlusPlus) {
15938 if (Record->isUnion()) {
15939 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
15940 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl());
15941 if (RDecl->getDefinition()) {
15942 // C++ [class.union]p1: An object of a class with a non-trivial
15943 // constructor, a non-trivial copy constructor, a non-trivial
15944 // destructor, or a non-trivial copy assignment operator
15945 // cannot be a member of a union, nor can an array of such
15947 if (CheckNontrivialField(NewFD))
15948 NewFD->setInvalidDecl();
15952 // C++ [class.union]p1: If a union contains a member of reference type,
15953 // the program is ill-formed, except when compiling with MSVC extensions
15955 if (EltTy->isReferenceType()) {
15956 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
15957 diag::ext_union_member_of_reference_type :
15958 diag::err_union_member_of_reference_type)
15959 << NewFD->getDeclName() << EltTy;
15960 if (!getLangOpts().MicrosoftExt)
15961 NewFD->setInvalidDecl();
15966 // FIXME: We need to pass in the attributes given an AST
15967 // representation, not a parser representation.
15969 // FIXME: The current scope is almost... but not entirely... correct here.
15970 ProcessDeclAttributes(getCurScope(), NewFD, *D);
15972 if (NewFD->hasAttrs())
15973 CheckAlignasUnderalignment(NewFD);
15976 // In auto-retain/release, infer strong retension for fields of
15977 // retainable type.
15978 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewFD))
15979 NewFD->setInvalidDecl();
15981 if (T.isObjCGCWeak())
15982 Diag(Loc, diag::warn_attribute_weak_on_field);
15984 NewFD->setAccess(AS);
15988 bool Sema::CheckNontrivialField(FieldDecl *FD) {
15990 assert(getLangOpts().CPlusPlus && "valid check only for C++");
15992 if (FD->isInvalidDecl() || FD->getType()->isDependentType())
15995 QualType EltTy = Context.getBaseElementType(FD->getType());
15996 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
15997 CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl());
15998 if (RDecl->getDefinition()) {
15999 // We check for copy constructors before constructors
16000 // because otherwise we'll never get complaints about
16001 // copy constructors.
16003 CXXSpecialMember member = CXXInvalid;
16004 // We're required to check for any non-trivial constructors. Since the
16005 // implicit default constructor is suppressed if there are any
16006 // user-declared constructors, we just need to check that there is a
16007 // trivial default constructor and a trivial copy constructor. (We don't
16008 // worry about move constructors here, since this is a C++98 check.)
16009 if (RDecl->hasNonTrivialCopyConstructor())
16010 member = CXXCopyConstructor;
16011 else if (!RDecl->hasTrivialDefaultConstructor())
16012 member = CXXDefaultConstructor;
16013 else if (RDecl->hasNonTrivialCopyAssignment())
16014 member = CXXCopyAssignment;
16015 else if (RDecl->hasNonTrivialDestructor())
16016 member = CXXDestructor;
16018 if (member != CXXInvalid) {
16019 if (!getLangOpts().CPlusPlus11 &&
16020 getLangOpts().ObjCAutoRefCount && RDecl->hasObjectMember()) {
16021 // Objective-C++ ARC: it is an error to have a non-trivial field of
16022 // a union. However, system headers in Objective-C programs
16023 // occasionally have Objective-C lifetime objects within unions,
16024 // and rather than cause the program to fail, we make those
16025 // members unavailable.
16026 SourceLocation Loc = FD->getLocation();
16027 if (getSourceManager().isInSystemHeader(Loc)) {
16028 if (!FD->hasAttr<UnavailableAttr>())
16029 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
16030 UnavailableAttr::IR_ARCFieldWithOwnership, Loc));
16035 Diag(FD->getLocation(), getLangOpts().CPlusPlus11 ?
16036 diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member :
16037 diag::err_illegal_union_or_anon_struct_member)
16038 << FD->getParent()->isUnion() << FD->getDeclName() << member;
16039 DiagnoseNontrivial(RDecl, member);
16040 return !getLangOpts().CPlusPlus11;
16048 /// TranslateIvarVisibility - Translate visibility from a token ID to an
16049 /// AST enum value.
16050 static ObjCIvarDecl::AccessControl
16051 TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) {
16052 switch (ivarVisibility) {
16053 default: llvm_unreachable("Unknown visitibility kind");
16054 case tok::objc_private: return ObjCIvarDecl::Private;
16055 case tok::objc_public: return ObjCIvarDecl::Public;
16056 case tok::objc_protected: return ObjCIvarDecl::Protected;
16057 case tok::objc_package: return ObjCIvarDecl::Package;
16061 /// ActOnIvar - Each ivar field of an objective-c class is passed into this
16062 /// in order to create an IvarDecl object for it.
16063 Decl *Sema::ActOnIvar(Scope *S,
16064 SourceLocation DeclStart,
16065 Declarator &D, Expr *BitfieldWidth,
16066 tok::ObjCKeywordKind Visibility) {
16068 IdentifierInfo *II = D.getIdentifier();
16069 Expr *BitWidth = (Expr*)BitfieldWidth;
16070 SourceLocation Loc = DeclStart;
16071 if (II) Loc = D.getIdentifierLoc();
16073 // FIXME: Unnamed fields can be handled in various different ways, for
16074 // example, unnamed unions inject all members into the struct namespace!
16076 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
16077 QualType T = TInfo->getType();
16080 // 6.7.2.1p3, 6.7.2.1p4
16081 BitWidth = VerifyBitField(Loc, II, T, /*IsMsStruct*/false, BitWidth).get();
16083 D.setInvalidType();
16090 if (T->isReferenceType()) {
16091 Diag(Loc, diag::err_ivar_reference_type);
16092 D.setInvalidType();
16094 // C99 6.7.2.1p8: A member of a structure or union may have any type other
16095 // than a variably modified type.
16096 else if (T->isVariablyModifiedType()) {
16097 Diag(Loc, diag::err_typecheck_ivar_variable_size);
16098 D.setInvalidType();
16101 // Get the visibility (access control) for this ivar.
16102 ObjCIvarDecl::AccessControl ac =
16103 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility)
16104 : ObjCIvarDecl::None;
16105 // Must set ivar's DeclContext to its enclosing interface.
16106 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(CurContext);
16107 if (!EnclosingDecl || EnclosingDecl->isInvalidDecl())
16109 ObjCContainerDecl *EnclosingContext;
16110 if (ObjCImplementationDecl *IMPDecl =
16111 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
16112 if (LangOpts.ObjCRuntime.isFragile()) {
16113 // Case of ivar declared in an implementation. Context is that of its class.
16114 EnclosingContext = IMPDecl->getClassInterface();
16115 assert(EnclosingContext && "Implementation has no class interface!");
16118 EnclosingContext = EnclosingDecl;
16120 if (ObjCCategoryDecl *CDecl =
16121 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
16122 if (LangOpts.ObjCRuntime.isFragile() || !CDecl->IsClassExtension()) {
16123 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension();
16127 EnclosingContext = EnclosingDecl;
16130 // Construct the decl.
16131 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext,
16132 DeclStart, Loc, II, T,
16133 TInfo, ac, (Expr *)BitfieldWidth);
16136 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName,
16137 ForVisibleRedeclaration);
16138 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S)
16139 && !isa<TagDecl>(PrevDecl)) {
16140 Diag(Loc, diag::err_duplicate_member) << II;
16141 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
16142 NewID->setInvalidDecl();
16146 // Process attributes attached to the ivar.
16147 ProcessDeclAttributes(S, NewID, D);
16149 if (D.isInvalidType())
16150 NewID->setInvalidDecl();
16152 // In ARC, infer 'retaining' for ivars of retainable type.
16153 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewID))
16154 NewID->setInvalidDecl();
16156 if (D.getDeclSpec().isModulePrivateSpecified())
16157 NewID->setModulePrivate();
16160 // FIXME: When interfaces are DeclContexts, we'll need to add
16161 // these to the interface.
16163 IdResolver.AddDecl(NewID);
16166 if (LangOpts.ObjCRuntime.isNonFragile() &&
16167 !NewID->isInvalidDecl() && isa<ObjCInterfaceDecl>(EnclosingDecl))
16168 Diag(Loc, diag::warn_ivars_in_interface);
16173 /// ActOnLastBitfield - This routine handles synthesized bitfields rules for
16174 /// class and class extensions. For every class \@interface and class
16175 /// extension \@interface, if the last ivar is a bitfield of any type,
16176 /// then add an implicit `char :0` ivar to the end of that interface.
16177 void Sema::ActOnLastBitfield(SourceLocation DeclLoc,
16178 SmallVectorImpl<Decl *> &AllIvarDecls) {
16179 if (LangOpts.ObjCRuntime.isFragile() || AllIvarDecls.empty())
16182 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1];
16183 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl);
16185 if (!Ivar->isBitField() || Ivar->isZeroLengthBitField(Context))
16187 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CurContext);
16189 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(CurContext)) {
16190 if (!CD->IsClassExtension())
16193 // No need to add this to end of @implementation.
16197 // All conditions are met. Add a new bitfield to the tail end of ivars.
16198 llvm::APInt Zero(Context.getTypeSize(Context.IntTy), 0);
16199 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.IntTy, DeclLoc);
16201 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(CurContext),
16202 DeclLoc, DeclLoc, nullptr,
16204 Context.getTrivialTypeSourceInfo(Context.CharTy,
16206 ObjCIvarDecl::Private, BW,
16208 AllIvarDecls.push_back(Ivar);
16211 void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
16212 ArrayRef<Decl *> Fields, SourceLocation LBrac,
16213 SourceLocation RBrac,
16214 const ParsedAttributesView &Attrs) {
16215 assert(EnclosingDecl && "missing record or interface decl");
16217 // If this is an Objective-C @implementation or category and we have
16218 // new fields here we should reset the layout of the interface since
16219 // it will now change.
16220 if (!Fields.empty() && isa<ObjCContainerDecl>(EnclosingDecl)) {
16221 ObjCContainerDecl *DC = cast<ObjCContainerDecl>(EnclosingDecl);
16222 switch (DC->getKind()) {
16224 case Decl::ObjCCategory:
16225 Context.ResetObjCLayout(cast<ObjCCategoryDecl>(DC)->getClassInterface());
16227 case Decl::ObjCImplementation:
16229 ResetObjCLayout(cast<ObjCImplementationDecl>(DC)->getClassInterface());
16234 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl);
16235 CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(EnclosingDecl);
16237 // Start counting up the number of named members; make sure to include
16238 // members of anonymous structs and unions in the total.
16239 unsigned NumNamedMembers = 0;
16241 for (const auto *I : Record->decls()) {
16242 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
16243 if (IFD->getDeclName())
16248 // Verify that all the fields are okay.
16249 SmallVector<FieldDecl*, 32> RecFields;
16251 for (ArrayRef<Decl *>::iterator i = Fields.begin(), end = Fields.end();
16253 FieldDecl *FD = cast<FieldDecl>(*i);
16255 // Get the type for the field.
16256 const Type *FDTy = FD->getType().getTypePtr();
16258 if (!FD->isAnonymousStructOrUnion()) {
16259 // Remember all fields written by the user.
16260 RecFields.push_back(FD);
16263 // If the field is already invalid for some reason, don't emit more
16264 // diagnostics about it.
16265 if (FD->isInvalidDecl()) {
16266 EnclosingDecl->setInvalidDecl();
16271 // A structure or union shall not contain a member with
16272 // incomplete or function type (hence, a structure shall not
16273 // contain an instance of itself, but may contain a pointer to
16274 // an instance of itself), except that the last member of a
16275 // structure with more than one named member may have incomplete
16276 // array type; such a structure (and any union containing,
16277 // possibly recursively, a member that is such a structure)
16278 // shall not be a member of a structure or an element of an
16280 bool IsLastField = (i + 1 == Fields.end());
16281 if (FDTy->isFunctionType()) {
16282 // Field declared as a function.
16283 Diag(FD->getLocation(), diag::err_field_declared_as_function)
16284 << FD->getDeclName();
16285 FD->setInvalidDecl();
16286 EnclosingDecl->setInvalidDecl();
16288 } else if (FDTy->isIncompleteArrayType() &&
16289 (Record || isa<ObjCContainerDecl>(EnclosingDecl))) {
16291 // Flexible array member.
16292 // Microsoft and g++ is more permissive regarding flexible array.
16293 // It will accept flexible array in union and also
16294 // as the sole element of a struct/class.
16295 unsigned DiagID = 0;
16296 if (!Record->isUnion() && !IsLastField) {
16297 Diag(FD->getLocation(), diag::err_flexible_array_not_at_end)
16298 << FD->getDeclName() << FD->getType() << Record->getTagKind();
16299 Diag((*(i + 1))->getLocation(), diag::note_next_field_declaration);
16300 FD->setInvalidDecl();
16301 EnclosingDecl->setInvalidDecl();
16303 } else if (Record->isUnion())
16304 DiagID = getLangOpts().MicrosoftExt
16305 ? diag::ext_flexible_array_union_ms
16306 : getLangOpts().CPlusPlus
16307 ? diag::ext_flexible_array_union_gnu
16308 : diag::err_flexible_array_union;
16309 else if (NumNamedMembers < 1)
16310 DiagID = getLangOpts().MicrosoftExt
16311 ? diag::ext_flexible_array_empty_aggregate_ms
16312 : getLangOpts().CPlusPlus
16313 ? diag::ext_flexible_array_empty_aggregate_gnu
16314 : diag::err_flexible_array_empty_aggregate;
16317 Diag(FD->getLocation(), DiagID) << FD->getDeclName()
16318 << Record->getTagKind();
16319 // While the layout of types that contain virtual bases is not specified
16320 // by the C++ standard, both the Itanium and Microsoft C++ ABIs place
16321 // virtual bases after the derived members. This would make a flexible
16322 // array member declared at the end of an object not adjacent to the end
16324 if (CXXRecord && CXXRecord->getNumVBases() != 0)
16325 Diag(FD->getLocation(), diag::err_flexible_array_virtual_base)
16326 << FD->getDeclName() << Record->getTagKind();
16327 if (!getLangOpts().C99)
16328 Diag(FD->getLocation(), diag::ext_c99_flexible_array_member)
16329 << FD->getDeclName() << Record->getTagKind();
16331 // If the element type has a non-trivial destructor, we would not
16332 // implicitly destroy the elements, so disallow it for now.
16334 // FIXME: GCC allows this. We should probably either implicitly delete
16335 // the destructor of the containing class, or just allow this.
16336 QualType BaseElem = Context.getBaseElementType(FD->getType());
16337 if (!BaseElem->isDependentType() && BaseElem.isDestructedType()) {
16338 Diag(FD->getLocation(), diag::err_flexible_array_has_nontrivial_dtor)
16339 << FD->getDeclName() << FD->getType();
16340 FD->setInvalidDecl();
16341 EnclosingDecl->setInvalidDecl();
16344 // Okay, we have a legal flexible array member at the end of the struct.
16345 Record->setHasFlexibleArrayMember(true);
16347 // In ObjCContainerDecl ivars with incomplete array type are accepted,
16348 // unless they are followed by another ivar. That check is done
16349 // elsewhere, after synthesized ivars are known.
16351 } else if (!FDTy->isDependentType() &&
16352 RequireCompleteType(FD->getLocation(), FD->getType(),
16353 diag::err_field_incomplete)) {
16355 FD->setInvalidDecl();
16356 EnclosingDecl->setInvalidDecl();
16358 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) {
16359 if (Record && FDTTy->getDecl()->hasFlexibleArrayMember()) {
16360 // A type which contains a flexible array member is considered to be a
16361 // flexible array member.
16362 Record->setHasFlexibleArrayMember(true);
16363 if (!Record->isUnion()) {
16364 // If this is a struct/class and this is not the last element, reject
16365 // it. Note that GCC supports variable sized arrays in the middle of
16368 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct)
16369 << FD->getDeclName() << FD->getType();
16371 // We support flexible arrays at the end of structs in
16372 // other structs as an extension.
16373 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct)
16374 << FD->getDeclName();
16378 if (isa<ObjCContainerDecl>(EnclosingDecl) &&
16379 RequireNonAbstractType(FD->getLocation(), FD->getType(),
16380 diag::err_abstract_type_in_decl,
16381 AbstractIvarType)) {
16382 // Ivars can not have abstract class types
16383 FD->setInvalidDecl();
16385 if (Record && FDTTy->getDecl()->hasObjectMember())
16386 Record->setHasObjectMember(true);
16387 if (Record && FDTTy->getDecl()->hasVolatileMember())
16388 Record->setHasVolatileMember(true);
16389 } else if (FDTy->isObjCObjectType()) {
16390 /// A field cannot be an Objective-c object
16391 Diag(FD->getLocation(), diag::err_statically_allocated_object)
16392 << FixItHint::CreateInsertion(FD->getLocation(), "*");
16393 QualType T = Context.getObjCObjectPointerType(FD->getType());
16395 } else if (getLangOpts().ObjC &&
16396 getLangOpts().getGC() != LangOptions::NonGC &&
16397 Record && !Record->hasObjectMember()) {
16398 if (FD->getType()->isObjCObjectPointerType() ||
16399 FD->getType().isObjCGCStrong())
16400 Record->setHasObjectMember(true);
16401 else if (Context.getAsArrayType(FD->getType())) {
16402 QualType BaseType = Context.getBaseElementType(FD->getType());
16403 if (BaseType->isRecordType() &&
16404 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember())
16405 Record->setHasObjectMember(true);
16406 else if (BaseType->isObjCObjectPointerType() ||
16407 BaseType.isObjCGCStrong())
16408 Record->setHasObjectMember(true);
16412 if (Record && !getLangOpts().CPlusPlus && !FD->hasAttr<UnavailableAttr>()) {
16413 QualType FT = FD->getType();
16414 if (FT.isNonTrivialToPrimitiveDefaultInitialize()) {
16415 Record->setNonTrivialToPrimitiveDefaultInitialize(true);
16416 if (FT.hasNonTrivialToPrimitiveDefaultInitializeCUnion() ||
16418 Record->setHasNonTrivialToPrimitiveDefaultInitializeCUnion(true);
16420 QualType::PrimitiveCopyKind PCK = FT.isNonTrivialToPrimitiveCopy();
16421 if (PCK != QualType::PCK_Trivial && PCK != QualType::PCK_VolatileTrivial) {
16422 Record->setNonTrivialToPrimitiveCopy(true);
16423 if (FT.hasNonTrivialToPrimitiveCopyCUnion() || Record->isUnion())
16424 Record->setHasNonTrivialToPrimitiveCopyCUnion(true);
16426 if (FT.isDestructedType()) {
16427 Record->setNonTrivialToPrimitiveDestroy(true);
16428 Record->setParamDestroyedInCallee(true);
16429 if (FT.hasNonTrivialToPrimitiveDestructCUnion() || Record->isUnion())
16430 Record->setHasNonTrivialToPrimitiveDestructCUnion(true);
16433 if (const auto *RT = FT->getAs<RecordType>()) {
16434 if (RT->getDecl()->getArgPassingRestrictions() ==
16435 RecordDecl::APK_CanNeverPassInRegs)
16436 Record->setArgPassingRestrictions(RecordDecl::APK_CanNeverPassInRegs);
16437 } else if (FT.getQualifiers().getObjCLifetime() == Qualifiers::OCL_Weak)
16438 Record->setArgPassingRestrictions(RecordDecl::APK_CanNeverPassInRegs);
16441 if (Record && FD->getType().isVolatileQualified())
16442 Record->setHasVolatileMember(true);
16443 // Keep track of the number of named members.
16444 if (FD->getIdentifier())
16448 // Okay, we successfully defined 'Record'.
16450 bool Completed = false;
16452 if (!CXXRecord->isInvalidDecl()) {
16453 // Set access bits correctly on the directly-declared conversions.
16454 for (CXXRecordDecl::conversion_iterator
16455 I = CXXRecord->conversion_begin(),
16456 E = CXXRecord->conversion_end(); I != E; ++I)
16457 I.setAccess((*I)->getAccess());
16460 if (!CXXRecord->isDependentType()) {
16461 // Add any implicitly-declared members to this class.
16462 AddImplicitlyDeclaredMembersToClass(CXXRecord);
16464 if (!CXXRecord->isInvalidDecl()) {
16465 // If we have virtual base classes, we may end up finding multiple
16466 // final overriders for a given virtual function. Check for this
16468 if (CXXRecord->getNumVBases()) {
16469 CXXFinalOverriderMap FinalOverriders;
16470 CXXRecord->getFinalOverriders(FinalOverriders);
16472 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
16473 MEnd = FinalOverriders.end();
16475 for (OverridingMethods::iterator SO = M->second.begin(),
16476 SOEnd = M->second.end();
16477 SO != SOEnd; ++SO) {
16478 assert(SO->second.size() > 0 &&
16479 "Virtual function without overriding functions?");
16480 if (SO->second.size() == 1)
16483 // C++ [class.virtual]p2:
16484 // In a derived class, if a virtual member function of a base
16485 // class subobject has more than one final overrider the
16486 // program is ill-formed.
16487 Diag(Record->getLocation(), diag::err_multiple_final_overriders)
16488 << (const NamedDecl *)M->first << Record;
16489 Diag(M->first->getLocation(),
16490 diag::note_overridden_virtual_function);
16491 for (OverridingMethods::overriding_iterator
16492 OM = SO->second.begin(),
16493 OMEnd = SO->second.end();
16495 Diag(OM->Method->getLocation(), diag::note_final_overrider)
16496 << (const NamedDecl *)M->first << OM->Method->getParent();
16498 Record->setInvalidDecl();
16501 CXXRecord->completeDefinition(&FinalOverriders);
16509 Record->completeDefinition();
16511 // Handle attributes before checking the layout.
16512 ProcessDeclAttributeList(S, Record, Attrs);
16514 // We may have deferred checking for a deleted destructor. Check now.
16516 auto *Dtor = CXXRecord->getDestructor();
16517 if (Dtor && Dtor->isImplicit() &&
16518 ShouldDeleteSpecialMember(Dtor, CXXDestructor)) {
16519 CXXRecord->setImplicitDestructorIsDeleted();
16520 SetDeclDeleted(Dtor, CXXRecord->getLocation());
16524 if (Record->hasAttrs()) {
16525 CheckAlignasUnderalignment(Record);
16527 if (const MSInheritanceAttr *IA = Record->getAttr<MSInheritanceAttr>())
16528 checkMSInheritanceAttrOnDefinition(cast<CXXRecordDecl>(Record),
16529 IA->getRange(), IA->getBestCase(),
16530 IA->getSemanticSpelling());
16533 // Check if the structure/union declaration is a type that can have zero
16534 // size in C. For C this is a language extension, for C++ it may cause
16535 // compatibility problems.
16536 bool CheckForZeroSize;
16537 if (!getLangOpts().CPlusPlus) {
16538 CheckForZeroSize = true;
16540 // For C++ filter out types that cannot be referenced in C code.
16541 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record);
16543 CXXRecord->getLexicalDeclContext()->isExternCContext() &&
16544 !CXXRecord->isDependentType() &&
16545 CXXRecord->isCLike();
16547 if (CheckForZeroSize) {
16548 bool ZeroSize = true;
16549 bool IsEmpty = true;
16550 unsigned NonBitFields = 0;
16551 for (RecordDecl::field_iterator I = Record->field_begin(),
16552 E = Record->field_end();
16553 (NonBitFields == 0 || ZeroSize) && I != E; ++I) {
16555 if (I->isUnnamedBitfield()) {
16556 if (!I->isZeroLengthBitField(Context))
16560 QualType FieldType = I->getType();
16561 if (FieldType->isIncompleteType() ||
16562 !Context.getTypeSizeInChars(FieldType).isZero())
16567 // Empty structs are an extension in C (C99 6.7.2.1p7). They are
16568 // allowed in C++, but warn if its declaration is inside
16569 // extern "C" block.
16571 Diag(RecLoc, getLangOpts().CPlusPlus ?
16572 diag::warn_zero_size_struct_union_in_extern_c :
16573 diag::warn_zero_size_struct_union_compat)
16574 << IsEmpty << Record->isUnion() << (NonBitFields > 1);
16577 // Structs without named members are extension in C (C99 6.7.2.1p7),
16578 // but are accepted by GCC.
16579 if (NonBitFields == 0 && !getLangOpts().CPlusPlus) {
16580 Diag(RecLoc, IsEmpty ? diag::ext_empty_struct_union :
16581 diag::ext_no_named_members_in_struct_union)
16582 << Record->isUnion();
16586 ObjCIvarDecl **ClsFields =
16587 reinterpret_cast<ObjCIvarDecl**>(RecFields.data());
16588 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) {
16589 ID->setEndOfDefinitionLoc(RBrac);
16590 // Add ivar's to class's DeclContext.
16591 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
16592 ClsFields[i]->setLexicalDeclContext(ID);
16593 ID->addDecl(ClsFields[i]);
16595 // Must enforce the rule that ivars in the base classes may not be
16597 if (ID->getSuperClass())
16598 DiagnoseDuplicateIvars(ID, ID->getSuperClass());
16599 } else if (ObjCImplementationDecl *IMPDecl =
16600 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
16601 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl");
16602 for (unsigned I = 0, N = RecFields.size(); I != N; ++I)
16603 // Ivar declared in @implementation never belongs to the implementation.
16604 // Only it is in implementation's lexical context.
16605 ClsFields[I]->setLexicalDeclContext(IMPDecl);
16606 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac);
16607 IMPDecl->setIvarLBraceLoc(LBrac);
16608 IMPDecl->setIvarRBraceLoc(RBrac);
16609 } else if (ObjCCategoryDecl *CDecl =
16610 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
16611 // case of ivars in class extension; all other cases have been
16612 // reported as errors elsewhere.
16613 // FIXME. Class extension does not have a LocEnd field.
16614 // CDecl->setLocEnd(RBrac);
16615 // Add ivar's to class extension's DeclContext.
16616 // Diagnose redeclaration of private ivars.
16617 ObjCInterfaceDecl *IDecl = CDecl->getClassInterface();
16618 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
16620 if (const ObjCIvarDecl *ClsIvar =
16621 IDecl->getIvarDecl(ClsFields[i]->getIdentifier())) {
16622 Diag(ClsFields[i]->getLocation(),
16623 diag::err_duplicate_ivar_declaration);
16624 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
16627 for (const auto *Ext : IDecl->known_extensions()) {
16628 if (const ObjCIvarDecl *ClsExtIvar
16629 = Ext->getIvarDecl(ClsFields[i]->getIdentifier())) {
16630 Diag(ClsFields[i]->getLocation(),
16631 diag::err_duplicate_ivar_declaration);
16632 Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
16637 ClsFields[i]->setLexicalDeclContext(CDecl);
16638 CDecl->addDecl(ClsFields[i]);
16640 CDecl->setIvarLBraceLoc(LBrac);
16641 CDecl->setIvarRBraceLoc(RBrac);
16646 /// Determine whether the given integral value is representable within
16647 /// the given type T.
16648 static bool isRepresentableIntegerValue(ASTContext &Context,
16649 llvm::APSInt &Value,
16651 assert((T->isIntegralType(Context) || T->isEnumeralType()) &&
16652 "Integral type required!");
16653 unsigned BitWidth = Context.getIntWidth(T);
16655 if (Value.isUnsigned() || Value.isNonNegative()) {
16656 if (T->isSignedIntegerOrEnumerationType())
16658 return Value.getActiveBits() <= BitWidth;
16660 return Value.getMinSignedBits() <= BitWidth;
16663 // Given an integral type, return the next larger integral type
16664 // (or a NULL type of no such type exists).
16665 static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) {
16666 // FIXME: Int128/UInt128 support, which also needs to be introduced into
16667 // enum checking below.
16668 assert((T->isIntegralType(Context) ||
16669 T->isEnumeralType()) && "Integral type required!");
16670 const unsigned NumTypes = 4;
16671 QualType SignedIntegralTypes[NumTypes] = {
16672 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy
16674 QualType UnsignedIntegralTypes[NumTypes] = {
16675 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy,
16676 Context.UnsignedLongLongTy
16679 unsigned BitWidth = Context.getTypeSize(T);
16680 QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes
16681 : UnsignedIntegralTypes;
16682 for (unsigned I = 0; I != NumTypes; ++I)
16683 if (Context.getTypeSize(Types[I]) > BitWidth)
16689 EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum,
16690 EnumConstantDecl *LastEnumConst,
16691 SourceLocation IdLoc,
16692 IdentifierInfo *Id,
16694 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
16695 llvm::APSInt EnumVal(IntWidth);
16698 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue))
16702 Val = DefaultLvalueConversion(Val).get();
16705 if (Enum->isDependentType() || Val->isTypeDependent())
16706 EltTy = Context.DependentTy;
16708 if (getLangOpts().CPlusPlus11 && Enum->isFixed() &&
16709 !getLangOpts().MSVCCompat) {
16710 // C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the
16711 // constant-expression in the enumerator-definition shall be a converted
16712 // constant expression of the underlying type.
16713 EltTy = Enum->getIntegerType();
16714 ExprResult Converted =
16715 CheckConvertedConstantExpression(Val, EltTy, EnumVal,
16717 if (Converted.isInvalid())
16720 Val = Converted.get();
16721 } else if (!Val->isValueDependent() &&
16722 !(Val = VerifyIntegerConstantExpression(Val,
16723 &EnumVal).get())) {
16724 // C99 6.7.2.2p2: Make sure we have an integer constant expression.
16726 if (Enum->isComplete()) {
16727 EltTy = Enum->getIntegerType();
16729 // In Obj-C and Microsoft mode, require the enumeration value to be
16730 // representable in the underlying type of the enumeration. In C++11,
16731 // we perform a non-narrowing conversion as part of converted constant
16732 // expression checking.
16733 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
16734 if (getLangOpts().MSVCCompat) {
16735 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy;
16736 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
16738 Diag(IdLoc, diag::err_enumerator_too_large) << EltTy;
16740 Val = ImpCastExprToType(Val, EltTy,
16741 EltTy->isBooleanType() ?
16742 CK_IntegralToBoolean : CK_IntegralCast)
16744 } else if (getLangOpts().CPlusPlus) {
16745 // C++11 [dcl.enum]p5:
16746 // If the underlying type is not fixed, the type of each enumerator
16747 // is the type of its initializing value:
16748 // - If an initializer is specified for an enumerator, the
16749 // initializing value has the same type as the expression.
16750 EltTy = Val->getType();
16753 // The expression that defines the value of an enumeration constant
16754 // shall be an integer constant expression that has a value
16755 // representable as an int.
16757 // Complain if the value is not representable in an int.
16758 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy))
16759 Diag(IdLoc, diag::ext_enum_value_not_int)
16760 << EnumVal.toString(10) << Val->getSourceRange()
16761 << (EnumVal.isUnsigned() || EnumVal.isNonNegative());
16762 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) {
16763 // Force the type of the expression to 'int'.
16764 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).get();
16766 EltTy = Val->getType();
16773 if (Enum->isDependentType())
16774 EltTy = Context.DependentTy;
16775 else if (!LastEnumConst) {
16776 // C++0x [dcl.enum]p5:
16777 // If the underlying type is not fixed, the type of each enumerator
16778 // is the type of its initializing value:
16779 // - If no initializer is specified for the first enumerator, the
16780 // initializing value has an unspecified integral type.
16782 // GCC uses 'int' for its unspecified integral type, as does
16784 if (Enum->isFixed()) {
16785 EltTy = Enum->getIntegerType();
16788 EltTy = Context.IntTy;
16791 // Assign the last value + 1.
16792 EnumVal = LastEnumConst->getInitVal();
16794 EltTy = LastEnumConst->getType();
16796 // Check for overflow on increment.
16797 if (EnumVal < LastEnumConst->getInitVal()) {
16798 // C++0x [dcl.enum]p5:
16799 // If the underlying type is not fixed, the type of each enumerator
16800 // is the type of its initializing value:
16802 // - Otherwise the type of the initializing value is the same as
16803 // the type of the initializing value of the preceding enumerator
16804 // unless the incremented value is not representable in that type,
16805 // in which case the type is an unspecified integral type
16806 // sufficient to contain the incremented value. If no such type
16807 // exists, the program is ill-formed.
16808 QualType T = getNextLargerIntegralType(Context, EltTy);
16809 if (T.isNull() || Enum->isFixed()) {
16810 // There is no integral type larger enough to represent this
16811 // value. Complain, then allow the value to wrap around.
16812 EnumVal = LastEnumConst->getInitVal();
16813 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2);
16815 if (Enum->isFixed())
16816 // When the underlying type is fixed, this is ill-formed.
16817 Diag(IdLoc, diag::err_enumerator_wrapped)
16818 << EnumVal.toString(10)
16821 Diag(IdLoc, diag::ext_enumerator_increment_too_large)
16822 << EnumVal.toString(10);
16827 // Retrieve the last enumerator's value, extent that type to the
16828 // type that is supposed to be large enough to represent the incremented
16829 // value, then increment.
16830 EnumVal = LastEnumConst->getInitVal();
16831 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
16832 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy));
16835 // If we're not in C++, diagnose the overflow of enumerator values,
16836 // which in C99 means that the enumerator value is not representable in
16837 // an int (C99 6.7.2.2p2). However, we support GCC's extension that
16838 // permits enumerator values that are representable in some larger
16840 if (!getLangOpts().CPlusPlus && !T.isNull())
16841 Diag(IdLoc, diag::warn_enum_value_overflow);
16842 } else if (!getLangOpts().CPlusPlus &&
16843 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
16844 // Enforce C99 6.7.2.2p2 even when we compute the next value.
16845 Diag(IdLoc, diag::ext_enum_value_not_int)
16846 << EnumVal.toString(10) << 1;
16851 if (!EltTy->isDependentType()) {
16852 // Make the enumerator value match the signedness and size of the
16853 // enumerator's type.
16854 EnumVal = EnumVal.extOrTrunc(Context.getIntWidth(EltTy));
16855 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
16858 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy,
16862 Sema::SkipBodyInfo Sema::shouldSkipAnonEnumBody(Scope *S, IdentifierInfo *II,
16863 SourceLocation IILoc) {
16864 if (!(getLangOpts().Modules || getLangOpts().ModulesLocalVisibility) ||
16865 !getLangOpts().CPlusPlus)
16866 return SkipBodyInfo();
16868 // We have an anonymous enum definition. Look up the first enumerator to
16869 // determine if we should merge the definition with an existing one and
16871 NamedDecl *PrevDecl = LookupSingleName(S, II, IILoc, LookupOrdinaryName,
16872 forRedeclarationInCurContext());
16873 auto *PrevECD = dyn_cast_or_null<EnumConstantDecl>(PrevDecl);
16875 return SkipBodyInfo();
16877 EnumDecl *PrevED = cast<EnumDecl>(PrevECD->getDeclContext());
16879 if (!PrevED->getDeclName() && !hasVisibleDefinition(PrevED, &Hidden)) {
16881 Skip.Previous = Hidden;
16885 return SkipBodyInfo();
16888 Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst,
16889 SourceLocation IdLoc, IdentifierInfo *Id,
16890 const ParsedAttributesView &Attrs,
16891 SourceLocation EqualLoc, Expr *Val) {
16892 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl);
16893 EnumConstantDecl *LastEnumConst =
16894 cast_or_null<EnumConstantDecl>(lastEnumConst);
16896 // The scope passed in may not be a decl scope. Zip up the scope tree until
16897 // we find one that is.
16898 S = getNonFieldDeclScope(S);
16900 // Verify that there isn't already something declared with this name in this
16902 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName, ForVisibleRedeclaration);
16904 NamedDecl *PrevDecl = R.getAsSingle<NamedDecl>();
16906 if (PrevDecl && PrevDecl->isTemplateParameter()) {
16907 // Maybe we will complain about the shadowed template parameter.
16908 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl);
16909 // Just pretend that we didn't see the previous declaration.
16910 PrevDecl = nullptr;
16913 // C++ [class.mem]p15:
16914 // If T is the name of a class, then each of the following shall have a name
16915 // different from T:
16916 // - every enumerator of every member of class T that is an unscoped
16918 if (getLangOpts().CPlusPlus && !TheEnumDecl->isScoped())
16919 DiagnoseClassNameShadow(TheEnumDecl->getDeclContext(),
16920 DeclarationNameInfo(Id, IdLoc));
16922 EnumConstantDecl *New =
16923 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val);
16928 if (!TheEnumDecl->isScoped() && isa<ValueDecl>(PrevDecl)) {
16929 // Check for other kinds of shadowing not already handled.
16930 CheckShadow(New, PrevDecl, R);
16933 // When in C++, we may get a TagDecl with the same name; in this case the
16934 // enum constant will 'hide' the tag.
16935 assert((getLangOpts().CPlusPlus || !isa<TagDecl>(PrevDecl)) &&
16936 "Received TagDecl when not in C++!");
16937 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) {
16938 if (isa<EnumConstantDecl>(PrevDecl))
16939 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id;
16941 Diag(IdLoc, diag::err_redefinition) << Id;
16942 notePreviousDefinition(PrevDecl, IdLoc);
16947 // Process attributes.
16948 ProcessDeclAttributeList(S, New, Attrs);
16949 AddPragmaAttributes(S, New);
16951 // Register this decl in the current scope stack.
16952 New->setAccess(TheEnumDecl->getAccess());
16953 PushOnScopeChains(New, S);
16955 ActOnDocumentableDecl(New);
16960 // Returns true when the enum initial expression does not trigger the
16961 // duplicate enum warning. A few common cases are exempted as follows:
16962 // Element2 = Element1
16963 // Element2 = Element1 + 1
16964 // Element2 = Element1 - 1
16965 // Where Element2 and Element1 are from the same enum.
16966 static bool ValidDuplicateEnum(EnumConstantDecl *ECD, EnumDecl *Enum) {
16967 Expr *InitExpr = ECD->getInitExpr();
16970 InitExpr = InitExpr->IgnoreImpCasts();
16972 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(InitExpr)) {
16973 if (!BO->isAdditiveOp())
16975 IntegerLiteral *IL = dyn_cast<IntegerLiteral>(BO->getRHS());
16978 if (IL->getValue() != 1)
16981 InitExpr = BO->getLHS();
16984 // This checks if the elements are from the same enum.
16985 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InitExpr);
16989 EnumConstantDecl *EnumConstant = dyn_cast<EnumConstantDecl>(DRE->getDecl());
16993 if (cast<EnumDecl>(TagDecl::castFromDeclContext(ECD->getDeclContext())) !=
17000 // Emits a warning when an element is implicitly set a value that
17001 // a previous element has already been set to.
17002 static void CheckForDuplicateEnumValues(Sema &S, ArrayRef<Decl *> Elements,
17003 EnumDecl *Enum, QualType EnumType) {
17004 // Avoid anonymous enums
17005 if (!Enum->getIdentifier())
17008 // Only check for small enums.
17009 if (Enum->getNumPositiveBits() > 63 || Enum->getNumNegativeBits() > 64)
17012 if (S.Diags.isIgnored(diag::warn_duplicate_enum_values, Enum->getLocation()))
17015 typedef SmallVector<EnumConstantDecl *, 3> ECDVector;
17016 typedef SmallVector<std::unique_ptr<ECDVector>, 3> DuplicatesVector;
17018 typedef llvm::PointerUnion<EnumConstantDecl*, ECDVector*> DeclOrVector;
17019 typedef std::unordered_map<int64_t, DeclOrVector> ValueToVectorMap;
17021 // Use int64_t as a key to avoid needing special handling for DenseMap keys.
17022 auto EnumConstantToKey = [](const EnumConstantDecl *D) {
17023 llvm::APSInt Val = D->getInitVal();
17024 return Val.isSigned() ? Val.getSExtValue() : Val.getZExtValue();
17027 DuplicatesVector DupVector;
17028 ValueToVectorMap EnumMap;
17030 // Populate the EnumMap with all values represented by enum constants without
17032 for (auto *Element : Elements) {
17033 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Element);
17035 // Null EnumConstantDecl means a previous diagnostic has been emitted for
17036 // this constant. Skip this enum since it may be ill-formed.
17041 // Constants with initalizers are handled in the next loop.
17042 if (ECD->getInitExpr())
17045 // Duplicate values are handled in the next loop.
17046 EnumMap.insert({EnumConstantToKey(ECD), ECD});
17049 if (EnumMap.size() == 0)
17052 // Create vectors for any values that has duplicates.
17053 for (auto *Element : Elements) {
17054 // The last loop returned if any constant was null.
17055 EnumConstantDecl *ECD = cast<EnumConstantDecl>(Element);
17056 if (!ValidDuplicateEnum(ECD, Enum))
17059 auto Iter = EnumMap.find(EnumConstantToKey(ECD));
17060 if (Iter == EnumMap.end())
17063 DeclOrVector& Entry = Iter->second;
17064 if (EnumConstantDecl *D = Entry.dyn_cast<EnumConstantDecl*>()) {
17065 // Ensure constants are different.
17069 // Create new vector and push values onto it.
17070 auto Vec = llvm::make_unique<ECDVector>();
17072 Vec->push_back(ECD);
17074 // Update entry to point to the duplicates vector.
17077 // Store the vector somewhere we can consult later for quick emission of
17079 DupVector.emplace_back(std::move(Vec));
17083 ECDVector *Vec = Entry.get<ECDVector*>();
17084 // Make sure constants are not added more than once.
17085 if (*Vec->begin() == ECD)
17088 Vec->push_back(ECD);
17091 // Emit diagnostics.
17092 for (const auto &Vec : DupVector) {
17093 assert(Vec->size() > 1 && "ECDVector should have at least 2 elements.");
17095 // Emit warning for one enum constant.
17096 auto *FirstECD = Vec->front();
17097 S.Diag(FirstECD->getLocation(), diag::warn_duplicate_enum_values)
17098 << FirstECD << FirstECD->getInitVal().toString(10)
17099 << FirstECD->getSourceRange();
17101 // Emit one note for each of the remaining enum constants with
17103 for (auto *ECD : llvm::make_range(Vec->begin() + 1, Vec->end()))
17104 S.Diag(ECD->getLocation(), diag::note_duplicate_element)
17105 << ECD << ECD->getInitVal().toString(10)
17106 << ECD->getSourceRange();
17110 bool Sema::IsValueInFlagEnum(const EnumDecl *ED, const llvm::APInt &Val,
17111 bool AllowMask) const {
17112 assert(ED->isClosedFlag() && "looking for value in non-flag or open enum");
17113 assert(ED->isCompleteDefinition() && "expected enum definition");
17115 auto R = FlagBitsCache.insert(std::make_pair(ED, llvm::APInt()));
17116 llvm::APInt &FlagBits = R.first->second;
17119 for (auto *E : ED->enumerators()) {
17120 const auto &EVal = E->getInitVal();
17121 // Only single-bit enumerators introduce new flag values.
17122 if (EVal.isPowerOf2())
17123 FlagBits = FlagBits.zextOrSelf(EVal.getBitWidth()) | EVal;
17127 // A value is in a flag enum if either its bits are a subset of the enum's
17128 // flag bits (the first condition) or we are allowing masks and the same is
17129 // true of its complement (the second condition). When masks are allowed, we
17130 // allow the common idiom of ~(enum1 | enum2) to be a valid enum value.
17132 // While it's true that any value could be used as a mask, the assumption is
17133 // that a mask will have all of the insignificant bits set. Anything else is
17134 // likely a logic error.
17135 llvm::APInt FlagMask = ~FlagBits.zextOrTrunc(Val.getBitWidth());
17136 return !(FlagMask & Val) || (AllowMask && !(FlagMask & ~Val));
17139 void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceRange BraceRange,
17140 Decl *EnumDeclX, ArrayRef<Decl *> Elements, Scope *S,
17141 const ParsedAttributesView &Attrs) {
17142 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX);
17143 QualType EnumType = Context.getTypeDeclType(Enum);
17145 ProcessDeclAttributeList(S, Enum, Attrs);
17147 if (Enum->isDependentType()) {
17148 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
17149 EnumConstantDecl *ECD =
17150 cast_or_null<EnumConstantDecl>(Elements[i]);
17151 if (!ECD) continue;
17153 ECD->setType(EnumType);
17156 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0);
17160 // TODO: If the result value doesn't fit in an int, it must be a long or long
17161 // long value. ISO C does not support this, but GCC does as an extension,
17163 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
17164 unsigned CharWidth = Context.getTargetInfo().getCharWidth();
17165 unsigned ShortWidth = Context.getTargetInfo().getShortWidth();
17167 // Verify that all the values are okay, compute the size of the values, and
17168 // reverse the list.
17169 unsigned NumNegativeBits = 0;
17170 unsigned NumPositiveBits = 0;
17172 // Keep track of whether all elements have type int.
17173 bool AllElementsInt = true;
17175 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
17176 EnumConstantDecl *ECD =
17177 cast_or_null<EnumConstantDecl>(Elements[i]);
17178 if (!ECD) continue; // Already issued a diagnostic.
17180 const llvm::APSInt &InitVal = ECD->getInitVal();
17182 // Keep track of the size of positive and negative values.
17183 if (InitVal.isUnsigned() || InitVal.isNonNegative())
17184 NumPositiveBits = std::max(NumPositiveBits,
17185 (unsigned)InitVal.getActiveBits());
17187 NumNegativeBits = std::max(NumNegativeBits,
17188 (unsigned)InitVal.getMinSignedBits());
17190 // Keep track of whether every enum element has type int (very common).
17191 if (AllElementsInt)
17192 AllElementsInt = ECD->getType() == Context.IntTy;
17195 // Figure out the type that should be used for this enum.
17197 unsigned BestWidth;
17199 // C++0x N3000 [conv.prom]p3:
17200 // An rvalue of an unscoped enumeration type whose underlying
17201 // type is not fixed can be converted to an rvalue of the first
17202 // of the following types that can represent all the values of
17203 // the enumeration: int, unsigned int, long int, unsigned long
17204 // int, long long int, or unsigned long long int.
17206 // An identifier declared as an enumeration constant has type int.
17207 // The C99 rule is modified by a gcc extension
17208 QualType BestPromotionType;
17210 bool Packed = Enum->hasAttr<PackedAttr>();
17211 // -fshort-enums is the equivalent to specifying the packed attribute on all
17212 // enum definitions.
17213 if (LangOpts.ShortEnums)
17216 // If the enum already has a type because it is fixed or dictated by the
17217 // target, promote that type instead of analyzing the enumerators.
17218 if (Enum->isComplete()) {
17219 BestType = Enum->getIntegerType();
17220 if (BestType->isPromotableIntegerType())
17221 BestPromotionType = Context.getPromotedIntegerType(BestType);
17223 BestPromotionType = BestType;
17225 BestWidth = Context.getIntWidth(BestType);
17227 else if (NumNegativeBits) {
17228 // If there is a negative value, figure out the smallest integer type (of
17229 // int/long/longlong) that fits.
17230 // If it's packed, check also if it fits a char or a short.
17231 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
17232 BestType = Context.SignedCharTy;
17233 BestWidth = CharWidth;
17234 } else if (Packed && NumNegativeBits <= ShortWidth &&
17235 NumPositiveBits < ShortWidth) {
17236 BestType = Context.ShortTy;
17237 BestWidth = ShortWidth;
17238 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
17239 BestType = Context.IntTy;
17240 BestWidth = IntWidth;
17242 BestWidth = Context.getTargetInfo().getLongWidth();
17244 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) {
17245 BestType = Context.LongTy;
17247 BestWidth = Context.getTargetInfo().getLongLongWidth();
17249 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth)
17250 Diag(Enum->getLocation(), diag::ext_enum_too_large);
17251 BestType = Context.LongLongTy;
17254 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType);
17256 // If there is no negative value, figure out the smallest type that fits
17257 // all of the enumerator values.
17258 // If it's packed, check also if it fits a char or a short.
17259 if (Packed && NumPositiveBits <= CharWidth) {
17260 BestType = Context.UnsignedCharTy;
17261 BestPromotionType = Context.IntTy;
17262 BestWidth = CharWidth;
17263 } else if (Packed && NumPositiveBits <= ShortWidth) {
17264 BestType = Context.UnsignedShortTy;
17265 BestPromotionType = Context.IntTy;
17266 BestWidth = ShortWidth;
17267 } else if (NumPositiveBits <= IntWidth) {
17268 BestType = Context.UnsignedIntTy;
17269 BestWidth = IntWidth;
17271 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
17272 ? Context.UnsignedIntTy : Context.IntTy;
17273 } else if (NumPositiveBits <=
17274 (BestWidth = Context.getTargetInfo().getLongWidth())) {
17275 BestType = Context.UnsignedLongTy;
17277 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
17278 ? Context.UnsignedLongTy : Context.LongTy;
17280 BestWidth = Context.getTargetInfo().getLongLongWidth();
17281 assert(NumPositiveBits <= BestWidth &&
17282 "How could an initializer get larger than ULL?");
17283 BestType = Context.UnsignedLongLongTy;
17285 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
17286 ? Context.UnsignedLongLongTy : Context.LongLongTy;
17290 // Loop over all of the enumerator constants, changing their types to match
17291 // the type of the enum if needed.
17292 for (auto *D : Elements) {
17293 auto *ECD = cast_or_null<EnumConstantDecl>(D);
17294 if (!ECD) continue; // Already issued a diagnostic.
17296 // Standard C says the enumerators have int type, but we allow, as an
17297 // extension, the enumerators to be larger than int size. If each
17298 // enumerator value fits in an int, type it as an int, otherwise type it the
17299 // same as the enumerator decl itself. This means that in "enum { X = 1U }"
17300 // that X has type 'int', not 'unsigned'.
17302 // Determine whether the value fits into an int.
17303 llvm::APSInt InitVal = ECD->getInitVal();
17305 // If it fits into an integer type, force it. Otherwise force it to match
17306 // the enum decl type.
17310 if (!getLangOpts().CPlusPlus &&
17311 !Enum->isFixed() &&
17312 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) {
17313 NewTy = Context.IntTy;
17314 NewWidth = IntWidth;
17316 } else if (ECD->getType() == BestType) {
17317 // Already the right type!
17318 if (getLangOpts().CPlusPlus)
17319 // C++ [dcl.enum]p4: Following the closing brace of an
17320 // enum-specifier, each enumerator has the type of its
17322 ECD->setType(EnumType);
17326 NewWidth = BestWidth;
17327 NewSign = BestType->isSignedIntegerOrEnumerationType();
17330 // Adjust the APSInt value.
17331 InitVal = InitVal.extOrTrunc(NewWidth);
17332 InitVal.setIsSigned(NewSign);
17333 ECD->setInitVal(InitVal);
17335 // Adjust the Expr initializer and type.
17336 if (ECD->getInitExpr() &&
17337 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType()))
17338 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy,
17340 ECD->getInitExpr(),
17341 /*base paths*/ nullptr,
17343 if (getLangOpts().CPlusPlus)
17344 // C++ [dcl.enum]p4: Following the closing brace of an
17345 // enum-specifier, each enumerator has the type of its
17347 ECD->setType(EnumType);
17349 ECD->setType(NewTy);
17352 Enum->completeDefinition(BestType, BestPromotionType,
17353 NumPositiveBits, NumNegativeBits);
17355 CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType);
17357 if (Enum->isClosedFlag()) {
17358 for (Decl *D : Elements) {
17359 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(D);
17360 if (!ECD) continue; // Already issued a diagnostic.
17362 llvm::APSInt InitVal = ECD->getInitVal();
17363 if (InitVal != 0 && !InitVal.isPowerOf2() &&
17364 !IsValueInFlagEnum(Enum, InitVal, true))
17365 Diag(ECD->getLocation(), diag::warn_flag_enum_constant_out_of_range)
17370 // Now that the enum type is defined, ensure it's not been underaligned.
17371 if (Enum->hasAttrs())
17372 CheckAlignasUnderalignment(Enum);
17375 Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr,
17376 SourceLocation StartLoc,
17377 SourceLocation EndLoc) {
17378 StringLiteral *AsmString = cast<StringLiteral>(expr);
17380 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext,
17381 AsmString, StartLoc,
17383 CurContext->addDecl(New);
17387 void Sema::ActOnPragmaRedefineExtname(IdentifierInfo* Name,
17388 IdentifierInfo* AliasName,
17389 SourceLocation PragmaLoc,
17390 SourceLocation NameLoc,
17391 SourceLocation AliasNameLoc) {
17392 NamedDecl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc,
17393 LookupOrdinaryName);
17394 AsmLabelAttr *Attr =
17395 AsmLabelAttr::CreateImplicit(Context, AliasName->getName(), AliasNameLoc);
17397 // If a declaration that:
17398 // 1) declares a function or a variable
17399 // 2) has external linkage
17400 // already exists, add a label attribute to it.
17401 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
17402 if (isDeclExternC(PrevDecl))
17403 PrevDecl->addAttr(Attr);
17405 Diag(PrevDecl->getLocation(), diag::warn_redefine_extname_not_applied)
17406 << /*Variable*/(isa<FunctionDecl>(PrevDecl) ? 0 : 1) << PrevDecl;
17407 // Otherwise, add a label atttibute to ExtnameUndeclaredIdentifiers.
17409 (void)ExtnameUndeclaredIdentifiers.insert(std::make_pair(Name, Attr));
17412 void Sema::ActOnPragmaWeakID(IdentifierInfo* Name,
17413 SourceLocation PragmaLoc,
17414 SourceLocation NameLoc) {
17415 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName);
17418 PrevDecl->addAttr(WeakAttr::CreateImplicit(Context, PragmaLoc));
17420 (void)WeakUndeclaredIdentifiers.insert(
17421 std::pair<IdentifierInfo*,WeakInfo>
17422 (Name, WeakInfo((IdentifierInfo*)nullptr, NameLoc)));
17426 void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name,
17427 IdentifierInfo* AliasName,
17428 SourceLocation PragmaLoc,
17429 SourceLocation NameLoc,
17430 SourceLocation AliasNameLoc) {
17431 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc,
17432 LookupOrdinaryName);
17433 WeakInfo W = WeakInfo(Name, NameLoc);
17435 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
17436 if (!PrevDecl->hasAttr<AliasAttr>())
17437 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl))
17438 DeclApplyPragmaWeak(TUScope, ND, W);
17440 (void)WeakUndeclaredIdentifiers.insert(
17441 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W));
17445 Decl *Sema::getObjCDeclContext() const {
17446 return (dyn_cast_or_null<ObjCContainerDecl>(CurContext));