1 //===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements semantic analysis for declarations.
12 //===----------------------------------------------------------------------===//
14 #include "TypeLocBuilder.h"
15 #include "clang/AST/ASTConsumer.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/ASTLambda.h"
18 #include "clang/AST/CXXInheritance.h"
19 #include "clang/AST/CharUnits.h"
20 #include "clang/AST/CommentDiagnostic.h"
21 #include "clang/AST/DeclCXX.h"
22 #include "clang/AST/DeclObjC.h"
23 #include "clang/AST/DeclTemplate.h"
24 #include "clang/AST/EvaluatedExprVisitor.h"
25 #include "clang/AST/ExprCXX.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 : public CorrectionCandidateCallback {
67 TypeNameValidatorCCC(bool AllowInvalid, bool WantClass=false,
68 bool AllowTemplates=false)
69 : AllowInvalidDecl(AllowInvalid), WantClassName(WantClass),
70 AllowTemplates(AllowTemplates) {
71 WantExpressionKeywords = false;
72 WantCXXNamedCasts = false;
73 WantRemainingKeywords = false;
76 bool ValidateCandidate(const TypoCorrection &candidate) override {
77 if (NamedDecl *ND = candidate.getCorrectionDecl()) {
78 bool IsType = isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND);
79 bool AllowedTemplate = AllowTemplates && getAsTypeTemplateDecl(ND);
80 return (IsType || AllowedTemplate) &&
81 (AllowInvalidDecl || !ND->isInvalidDecl());
83 return !WantClassName && candidate.isKeyword();
87 bool AllowInvalidDecl;
92 } // end anonymous namespace
94 /// \brief Determine whether the token kind starts a simple-type-specifier.
95 bool Sema::isSimpleTypeSpecifier(tok::TokenKind Kind) const {
97 // FIXME: Take into account the current language when deciding whether a
98 // token kind is a valid type specifier
101 case tok::kw___int64:
102 case tok::kw___int128:
104 case tok::kw_unsigned:
111 case tok::kw___float128:
112 case tok::kw_wchar_t:
114 case tok::kw___underlying_type:
115 case tok::kw___auto_type:
118 case tok::annot_typename:
119 case tok::kw_char16_t:
120 case tok::kw_char32_t:
122 case tok::annot_decltype:
123 case tok::kw_decltype:
124 return getLangOpts().CPlusPlus;
134 enum class UnqualifiedTypeNameLookupResult {
139 } // end anonymous namespace
141 /// \brief Tries to perform unqualified lookup of the type decls in bases for
143 /// \return \a NotFound if no any decls is found, \a FoundNotType if found not a
144 /// type decl, \a FoundType if only type decls are found.
145 static UnqualifiedTypeNameLookupResult
146 lookupUnqualifiedTypeNameInBase(Sema &S, const IdentifierInfo &II,
147 SourceLocation NameLoc,
148 const CXXRecordDecl *RD) {
149 if (!RD->hasDefinition())
150 return UnqualifiedTypeNameLookupResult::NotFound;
151 // Look for type decls in base classes.
152 UnqualifiedTypeNameLookupResult FoundTypeDecl =
153 UnqualifiedTypeNameLookupResult::NotFound;
154 for (const auto &Base : RD->bases()) {
155 const CXXRecordDecl *BaseRD = nullptr;
156 if (auto *BaseTT = Base.getType()->getAs<TagType>())
157 BaseRD = BaseTT->getAsCXXRecordDecl();
158 else if (auto *TST = Base.getType()->getAs<TemplateSpecializationType>()) {
159 // Look for type decls in dependent base classes that have known primary
161 if (!TST || !TST->isDependentType())
163 auto *TD = TST->getTemplateName().getAsTemplateDecl();
166 if (auto *BasePrimaryTemplate =
167 dyn_cast_or_null<CXXRecordDecl>(TD->getTemplatedDecl())) {
168 if (BasePrimaryTemplate->getCanonicalDecl() != RD->getCanonicalDecl())
169 BaseRD = BasePrimaryTemplate;
170 else if (auto *CTD = dyn_cast<ClassTemplateDecl>(TD)) {
171 if (const ClassTemplatePartialSpecializationDecl *PS =
172 CTD->findPartialSpecialization(Base.getType()))
173 if (PS->getCanonicalDecl() != RD->getCanonicalDecl())
179 for (NamedDecl *ND : BaseRD->lookup(&II)) {
180 if (!isa<TypeDecl>(ND))
181 return UnqualifiedTypeNameLookupResult::FoundNonType;
182 FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
184 if (FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound) {
185 switch (lookupUnqualifiedTypeNameInBase(S, II, NameLoc, BaseRD)) {
186 case UnqualifiedTypeNameLookupResult::FoundNonType:
187 return UnqualifiedTypeNameLookupResult::FoundNonType;
188 case UnqualifiedTypeNameLookupResult::FoundType:
189 FoundTypeDecl = UnqualifiedTypeNameLookupResult::FoundType;
191 case UnqualifiedTypeNameLookupResult::NotFound:
198 return FoundTypeDecl;
201 static ParsedType recoverFromTypeInKnownDependentBase(Sema &S,
202 const IdentifierInfo &II,
203 SourceLocation NameLoc) {
204 // Lookup in the parent class template context, if any.
205 const CXXRecordDecl *RD = nullptr;
206 UnqualifiedTypeNameLookupResult FoundTypeDecl =
207 UnqualifiedTypeNameLookupResult::NotFound;
208 for (DeclContext *DC = S.CurContext;
209 DC && FoundTypeDecl == UnqualifiedTypeNameLookupResult::NotFound;
210 DC = DC->getParent()) {
211 // Look for type decls in dependent base classes that have known primary
213 RD = dyn_cast<CXXRecordDecl>(DC);
214 if (RD && RD->getDescribedClassTemplate())
215 FoundTypeDecl = lookupUnqualifiedTypeNameInBase(S, II, NameLoc, RD);
217 if (FoundTypeDecl != UnqualifiedTypeNameLookupResult::FoundType)
220 // We found some types in dependent base classes. Recover as if the user
221 // wrote 'typename MyClass::II' instead of 'II'. We'll fully resolve the
222 // lookup during template instantiation.
223 S.Diag(NameLoc, diag::ext_found_via_dependent_bases_lookup) << &II;
225 ASTContext &Context = S.Context;
226 auto *NNS = NestedNameSpecifier::Create(Context, nullptr, false,
227 cast<Type>(Context.getRecordType(RD)));
228 QualType T = Context.getDependentNameType(ETK_Typename, NNS, &II);
231 SS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
233 TypeLocBuilder Builder;
234 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
235 DepTL.setNameLoc(NameLoc);
236 DepTL.setElaboratedKeywordLoc(SourceLocation());
237 DepTL.setQualifierLoc(SS.getWithLocInContext(Context));
238 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
241 /// \brief If the identifier refers to a type name within this scope,
242 /// return the declaration of that type.
244 /// This routine performs ordinary name lookup of the identifier II
245 /// within the given scope, with optional C++ scope specifier SS, to
246 /// determine whether the name refers to a type. If so, returns an
247 /// opaque pointer (actually a QualType) corresponding to that
248 /// type. Otherwise, returns NULL.
249 ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
250 Scope *S, CXXScopeSpec *SS,
251 bool isClassName, bool HasTrailingDot,
252 ParsedType ObjectTypePtr,
253 bool IsCtorOrDtorName,
254 bool WantNontrivialTypeSourceInfo,
255 bool IsClassTemplateDeductionContext,
256 IdentifierInfo **CorrectedII) {
257 // FIXME: Consider allowing this outside C++1z mode as an extension.
258 bool AllowDeducedTemplate = IsClassTemplateDeductionContext &&
259 getLangOpts().CPlusPlus1z && !IsCtorOrDtorName &&
260 !isClassName && !HasTrailingDot;
262 // Determine where we will perform name lookup.
263 DeclContext *LookupCtx = nullptr;
265 QualType ObjectType = ObjectTypePtr.get();
266 if (ObjectType->isRecordType())
267 LookupCtx = computeDeclContext(ObjectType);
268 } else if (SS && SS->isNotEmpty()) {
269 LookupCtx = computeDeclContext(*SS, false);
272 if (isDependentScopeSpecifier(*SS)) {
274 // A qualified-id that refers to a type and in which the
275 // nested-name-specifier depends on a template-parameter (14.6.2)
276 // shall be prefixed by the keyword typename to indicate that the
277 // qualified-id denotes a type, forming an
278 // elaborated-type-specifier (7.1.5.3).
280 // We therefore do not perform any name lookup if the result would
281 // refer to a member of an unknown specialization.
282 if (!isClassName && !IsCtorOrDtorName)
285 // We know from the grammar that this name refers to a type,
286 // so build a dependent node to describe the type.
287 if (WantNontrivialTypeSourceInfo)
288 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get();
290 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context);
291 QualType T = CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc,
293 return ParsedType::make(T);
299 if (!LookupCtx->isDependentContext() &&
300 RequireCompleteDeclContext(*SS, LookupCtx))
304 // FIXME: LookupNestedNameSpecifierName isn't the right kind of
305 // lookup for class-names.
306 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName :
308 LookupResult Result(*this, &II, NameLoc, Kind);
310 // Perform "qualified" name lookup into the declaration context we
311 // computed, which is either the type of the base of a member access
312 // expression or the declaration context associated with a prior
313 // nested-name-specifier.
314 LookupQualifiedName(Result, LookupCtx);
316 if (ObjectTypePtr && Result.empty()) {
317 // C++ [basic.lookup.classref]p3:
318 // If the unqualified-id is ~type-name, the type-name is looked up
319 // in the context of the entire postfix-expression. If the type T of
320 // the object expression is of a class type C, the type-name is also
321 // looked up in the scope of class C. At least one of the lookups shall
322 // find a name that refers to (possibly cv-qualified) T.
323 LookupName(Result, S);
326 // Perform unqualified name lookup.
327 LookupName(Result, S);
329 // For unqualified lookup in a class template in MSVC mode, look into
330 // dependent base classes where the primary class template is known.
331 if (Result.empty() && getLangOpts().MSVCCompat && (!SS || SS->isEmpty())) {
332 if (ParsedType TypeInBase =
333 recoverFromTypeInKnownDependentBase(*this, II, NameLoc))
338 NamedDecl *IIDecl = nullptr;
339 switch (Result.getResultKind()) {
340 case LookupResult::NotFound:
341 case LookupResult::NotFoundInCurrentInstantiation:
343 TypoCorrection Correction =
344 CorrectTypo(Result.getLookupNameInfo(), Kind, S, SS,
345 llvm::make_unique<TypeNameValidatorCCC>(
346 true, isClassName, AllowDeducedTemplate),
348 IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo();
350 bool MemberOfUnknownSpecialization;
351 UnqualifiedId TemplateName;
352 TemplateName.setIdentifier(NewII, NameLoc);
353 NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier();
354 CXXScopeSpec NewSS, *NewSSPtr = SS;
356 NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
359 if (Correction && (NNS || NewII != &II) &&
360 // Ignore a correction to a template type as the to-be-corrected
361 // identifier is not a template (typo correction for template names
362 // is handled elsewhere).
363 !(getLangOpts().CPlusPlus && NewSSPtr &&
364 isTemplateName(S, *NewSSPtr, false, TemplateName, nullptr, false,
365 Template, MemberOfUnknownSpecialization))) {
366 ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr,
367 isClassName, HasTrailingDot, ObjectTypePtr,
369 WantNontrivialTypeSourceInfo,
370 IsClassTemplateDeductionContext);
372 diagnoseTypo(Correction,
373 PDiag(diag::err_unknown_type_or_class_name_suggest)
374 << Result.getLookupName() << isClassName);
376 SS->MakeTrivial(Context, NNS, SourceRange(NameLoc));
377 *CorrectedII = NewII;
382 // If typo correction failed or was not performed, fall through
383 case LookupResult::FoundOverloaded:
384 case LookupResult::FoundUnresolvedValue:
385 Result.suppressDiagnostics();
388 case LookupResult::Ambiguous:
389 // Recover from type-hiding ambiguities by hiding the type. We'll
390 // do the lookup again when looking for an object, and we can
391 // diagnose the error then. If we don't do this, then the error
392 // about hiding the type will be immediately followed by an error
393 // that only makes sense if the identifier was treated like a type.
394 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) {
395 Result.suppressDiagnostics();
399 // Look to see if we have a type anywhere in the list of results.
400 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end();
401 Res != ResEnd; ++Res) {
402 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res) ||
403 (AllowDeducedTemplate && getAsTypeTemplateDecl(*Res))) {
405 (*Res)->getLocation().getRawEncoding() <
406 IIDecl->getLocation().getRawEncoding())
412 // None of the entities we found is a type, so there is no way
413 // to even assume that the result is a type. In this case, don't
414 // complain about the ambiguity. The parser will either try to
415 // perform this lookup again (e.g., as an object name), which
416 // will produce the ambiguity, or will complain that it expected
418 Result.suppressDiagnostics();
422 // We found a type within the ambiguous lookup; diagnose the
423 // ambiguity and then return that type. This might be the right
424 // answer, or it might not be, but it suppresses any attempt to
425 // perform the name lookup again.
428 case LookupResult::Found:
429 IIDecl = Result.getFoundDecl();
433 assert(IIDecl && "Didn't find decl");
436 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) {
437 // C++ [class.qual]p2: A lookup that would find the injected-class-name
438 // instead names the constructors of the class, except when naming a class.
439 // This is ill-formed when we're not actually forming a ctor or dtor name.
440 auto *LookupRD = dyn_cast_or_null<CXXRecordDecl>(LookupCtx);
441 auto *FoundRD = dyn_cast<CXXRecordDecl>(TD);
442 if (!isClassName && !IsCtorOrDtorName && LookupRD && FoundRD &&
443 FoundRD->isInjectedClassName() &&
444 declaresSameEntity(LookupRD, cast<Decl>(FoundRD->getParent())))
445 Diag(NameLoc, diag::err_out_of_line_qualified_id_type_names_constructor)
448 DiagnoseUseOfDecl(IIDecl, NameLoc);
450 T = Context.getTypeDeclType(TD);
451 MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
452 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) {
453 (void)DiagnoseUseOfDecl(IDecl, NameLoc);
455 T = Context.getObjCInterfaceType(IDecl);
456 } else if (AllowDeducedTemplate) {
457 if (auto *TD = getAsTypeTemplateDecl(IIDecl))
458 T = Context.getDeducedTemplateSpecializationType(TemplateName(TD),
463 // If it's not plausibly a type, suppress diagnostics.
464 Result.suppressDiagnostics();
468 // NOTE: avoid constructing an ElaboratedType(Loc) if this is a
469 // constructor or destructor name (in such a case, the scope specifier
470 // will be attached to the enclosing Expr or Decl node).
471 if (SS && SS->isNotEmpty() && !IsCtorOrDtorName &&
472 !isa<ObjCInterfaceDecl>(IIDecl)) {
473 if (WantNontrivialTypeSourceInfo) {
474 // Construct a type with type-source information.
475 TypeLocBuilder Builder;
476 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
478 T = getElaboratedType(ETK_None, *SS, T);
479 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
480 ElabTL.setElaboratedKeywordLoc(SourceLocation());
481 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context));
482 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
484 T = getElaboratedType(ETK_None, *SS, T);
488 return ParsedType::make(T);
491 // Builds a fake NNS for the given decl context.
492 static NestedNameSpecifier *
493 synthesizeCurrentNestedNameSpecifier(ASTContext &Context, DeclContext *DC) {
494 for (;; DC = DC->getLookupParent()) {
495 DC = DC->getPrimaryContext();
496 auto *ND = dyn_cast<NamespaceDecl>(DC);
497 if (ND && !ND->isInline() && !ND->isAnonymousNamespace())
498 return NestedNameSpecifier::Create(Context, nullptr, ND);
499 else if (auto *RD = dyn_cast<CXXRecordDecl>(DC))
500 return NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
501 RD->getTypeForDecl());
502 else if (isa<TranslationUnitDecl>(DC))
503 return NestedNameSpecifier::GlobalSpecifier(Context);
505 llvm_unreachable("something isn't in TU scope?");
508 /// Find the parent class with dependent bases of the innermost enclosing method
509 /// context. Do not look for enclosing CXXRecordDecls directly, or we will end
510 /// up allowing unqualified dependent type names at class-level, which MSVC
511 /// correctly rejects.
512 static const CXXRecordDecl *
513 findRecordWithDependentBasesOfEnclosingMethod(const DeclContext *DC) {
514 for (; DC && DC->isDependentContext(); DC = DC->getLookupParent()) {
515 DC = DC->getPrimaryContext();
516 if (const auto *MD = dyn_cast<CXXMethodDecl>(DC))
517 if (MD->getParent()->hasAnyDependentBases())
518 return MD->getParent();
523 ParsedType Sema::ActOnMSVCUnknownTypeName(const IdentifierInfo &II,
524 SourceLocation NameLoc,
525 bool IsTemplateTypeArg) {
526 assert(getLangOpts().MSVCCompat && "shouldn't be called in non-MSVC mode");
528 NestedNameSpecifier *NNS = nullptr;
529 if (IsTemplateTypeArg && getCurScope()->isTemplateParamScope()) {
530 // If we weren't able to parse a default template argument, delay lookup
531 // until instantiation time by making a non-dependent DependentTypeName. We
532 // pretend we saw a NestedNameSpecifier referring to the current scope, and
533 // lookup is retried.
534 // FIXME: This hurts our diagnostic quality, since we get errors like "no
535 // type named 'Foo' in 'current_namespace'" when the user didn't write any
537 NNS = synthesizeCurrentNestedNameSpecifier(Context, CurContext);
538 Diag(NameLoc, diag::ext_ms_delayed_template_argument) << &II;
539 } else if (const CXXRecordDecl *RD =
540 findRecordWithDependentBasesOfEnclosingMethod(CurContext)) {
541 // Build a DependentNameType that will perform lookup into RD at
542 // instantiation time.
543 NNS = NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
544 RD->getTypeForDecl());
546 // Diagnose that this identifier was undeclared, and retry the lookup during
547 // template instantiation.
548 Diag(NameLoc, diag::ext_undeclared_unqual_id_with_dependent_base) << &II
551 // This is not a situation that we should recover from.
555 QualType T = Context.getDependentNameType(ETK_None, NNS, &II);
557 // Build type location information. We synthesized the qualifier, so we have
558 // to build a fake NestedNameSpecifierLoc.
559 NestedNameSpecifierLocBuilder NNSLocBuilder;
560 NNSLocBuilder.MakeTrivial(Context, NNS, SourceRange(NameLoc));
561 NestedNameSpecifierLoc QualifierLoc = NNSLocBuilder.getWithLocInContext(Context);
563 TypeLocBuilder Builder;
564 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
565 DepTL.setNameLoc(NameLoc);
566 DepTL.setElaboratedKeywordLoc(SourceLocation());
567 DepTL.setQualifierLoc(QualifierLoc);
568 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
571 /// isTagName() - This method is called *for error recovery purposes only*
572 /// to determine if the specified name is a valid tag name ("struct foo"). If
573 /// so, this returns the TST for the tag corresponding to it (TST_enum,
574 /// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose
575 /// cases in C where the user forgot to specify the tag.
576 DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) {
577 // Do a tag name lookup in this scope.
578 LookupResult R(*this, &II, SourceLocation(), LookupTagName);
579 LookupName(R, S, false);
580 R.suppressDiagnostics();
581 if (R.getResultKind() == LookupResult::Found)
582 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) {
583 switch (TD->getTagKind()) {
584 case TTK_Struct: return DeclSpec::TST_struct;
585 case TTK_Interface: return DeclSpec::TST_interface;
586 case TTK_Union: return DeclSpec::TST_union;
587 case TTK_Class: return DeclSpec::TST_class;
588 case TTK_Enum: return DeclSpec::TST_enum;
592 return DeclSpec::TST_unspecified;
595 /// isMicrosoftMissingTypename - In Microsoft mode, within class scope,
596 /// if a CXXScopeSpec's type is equal to the type of one of the base classes
597 /// then downgrade the missing typename error to a warning.
598 /// This is needed for MSVC compatibility; Example:
600 /// template<class T> class A {
602 /// typedef int TYPE;
604 /// template<class T> class B : public A<T> {
606 /// A<T>::TYPE a; // no typename required because A<T> is a base class.
609 bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) {
610 if (CurContext->isRecord()) {
611 if (SS->getScopeRep()->getKind() == NestedNameSpecifier::Super)
614 const Type *Ty = SS->getScopeRep()->getAsType();
616 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext);
617 for (const auto &Base : RD->bases())
618 if (Ty && Context.hasSameUnqualifiedType(QualType(Ty, 1), Base.getType()))
620 return S->isFunctionPrototypeScope();
622 return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope();
625 void Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II,
626 SourceLocation IILoc,
629 ParsedType &SuggestedType,
630 bool AllowClassTemplates) {
631 // Don't report typename errors for editor placeholders.
632 if (II->isEditorPlaceholder())
634 // We don't have anything to suggest (yet).
635 SuggestedType = nullptr;
637 // There may have been a typo in the name of the type. Look up typo
638 // results, in case we have something that we can suggest.
639 if (TypoCorrection Corrected =
640 CorrectTypo(DeclarationNameInfo(II, IILoc), LookupOrdinaryName, S, SS,
641 llvm::make_unique<TypeNameValidatorCCC>(
642 false, false, AllowClassTemplates),
643 CTK_ErrorRecovery)) {
644 if (Corrected.isKeyword()) {
645 // We corrected to a keyword.
646 diagnoseTypo(Corrected, PDiag(diag::err_unknown_typename_suggest) << II);
647 II = Corrected.getCorrectionAsIdentifierInfo();
649 // We found a similarly-named type or interface; suggest that.
650 if (!SS || !SS->isSet()) {
651 diagnoseTypo(Corrected,
652 PDiag(diag::err_unknown_typename_suggest) << II);
653 } else if (DeclContext *DC = computeDeclContext(*SS, false)) {
654 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
655 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
656 II->getName().equals(CorrectedStr);
657 diagnoseTypo(Corrected,
658 PDiag(diag::err_unknown_nested_typename_suggest)
659 << II << DC << DroppedSpecifier << SS->getRange());
661 llvm_unreachable("could not have corrected a typo here");
665 if (Corrected.getCorrectionSpecifier())
666 tmpSS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
668 // FIXME: Support class template argument deduction here.
670 getTypeName(*Corrected.getCorrectionAsIdentifierInfo(), IILoc, S,
671 tmpSS.isSet() ? &tmpSS : SS, false, false, nullptr,
672 /*IsCtorOrDtorName=*/false,
673 /*NonTrivialTypeSourceInfo=*/true);
678 if (getLangOpts().CPlusPlus) {
679 // See if II is a class template that the user forgot to pass arguments to.
681 Name.setIdentifier(II, IILoc);
682 CXXScopeSpec EmptySS;
683 TemplateTy TemplateResult;
684 bool MemberOfUnknownSpecialization;
685 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false,
686 Name, nullptr, true, TemplateResult,
687 MemberOfUnknownSpecialization) == TNK_Type_template) {
688 TemplateName TplName = TemplateResult.get();
689 Diag(IILoc, diag::err_template_missing_args)
690 << (int)getTemplateNameKindForDiagnostics(TplName) << TplName;
691 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) {
692 Diag(TplDecl->getLocation(), diag::note_template_decl_here)
693 << TplDecl->getTemplateParameters()->getSourceRange();
699 // FIXME: Should we move the logic that tries to recover from a missing tag
700 // (struct, union, enum) from Parser::ParseImplicitInt here, instead?
702 if (!SS || (!SS->isSet() && !SS->isInvalid()))
703 Diag(IILoc, diag::err_unknown_typename) << II;
704 else if (DeclContext *DC = computeDeclContext(*SS, false))
705 Diag(IILoc, diag::err_typename_nested_not_found)
706 << II << DC << SS->getRange();
707 else if (isDependentScopeSpecifier(*SS)) {
708 unsigned DiagID = diag::err_typename_missing;
709 if (getLangOpts().MSVCCompat && isMicrosoftMissingTypename(SS, S))
710 DiagID = diag::ext_typename_missing;
712 Diag(SS->getRange().getBegin(), DiagID)
713 << SS->getScopeRep() << II->getName()
714 << SourceRange(SS->getRange().getBegin(), IILoc)
715 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename ");
716 SuggestedType = ActOnTypenameType(S, SourceLocation(),
717 *SS, *II, IILoc).get();
719 assert(SS && SS->isInvalid() &&
720 "Invalid scope specifier has already been diagnosed");
724 /// \brief Determine whether the given result set contains either a type name
726 static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) {
727 bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus &&
728 NextToken.is(tok::less);
730 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) {
731 if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I))
734 if (CheckTemplate && isa<TemplateDecl>(*I))
741 static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result,
742 Scope *S, CXXScopeSpec &SS,
743 IdentifierInfo *&Name,
744 SourceLocation NameLoc) {
745 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName);
746 SemaRef.LookupParsedName(R, S, &SS);
747 if (TagDecl *Tag = R.getAsSingle<TagDecl>()) {
748 StringRef FixItTagName;
749 switch (Tag->getTagKind()) {
751 FixItTagName = "class ";
755 FixItTagName = "enum ";
759 FixItTagName = "struct ";
763 FixItTagName = "__interface ";
767 FixItTagName = "union ";
771 StringRef TagName = FixItTagName.drop_back();
772 SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag)
773 << Name << TagName << SemaRef.getLangOpts().CPlusPlus
774 << FixItHint::CreateInsertion(NameLoc, FixItTagName);
776 for (LookupResult::iterator I = Result.begin(), IEnd = Result.end();
778 SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type)
781 // Replace lookup results with just the tag decl.
782 Result.clear(Sema::LookupTagName);
783 SemaRef.LookupParsedName(Result, S, &SS);
790 /// Build a ParsedType for a simple-type-specifier with a nested-name-specifier.
791 static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS,
792 QualType T, SourceLocation NameLoc) {
793 ASTContext &Context = S.Context;
795 TypeLocBuilder Builder;
796 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
798 T = S.getElaboratedType(ETK_None, SS, T);
799 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
800 ElabTL.setElaboratedKeywordLoc(SourceLocation());
801 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
802 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
805 Sema::NameClassification
806 Sema::ClassifyName(Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name,
807 SourceLocation NameLoc, const Token &NextToken,
808 bool IsAddressOfOperand,
809 std::unique_ptr<CorrectionCandidateCallback> CCC) {
810 DeclarationNameInfo NameInfo(Name, NameLoc);
811 ObjCMethodDecl *CurMethod = getCurMethodDecl();
813 if (NextToken.is(tok::coloncolon)) {
814 NestedNameSpecInfo IdInfo(Name, NameLoc, NextToken.getLocation());
815 BuildCXXNestedNameSpecifier(S, IdInfo, false, SS, nullptr, false);
816 } else if (getLangOpts().CPlusPlus && SS.isSet() &&
817 isCurrentClassName(*Name, S, &SS)) {
818 // Per [class.qual]p2, this names the constructors of SS, not the
819 // injected-class-name. We don't have a classification for that.
820 // There's not much point caching this result, since the parser
821 // will reject it later.
822 return NameClassification::Unknown();
825 LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName);
826 LookupParsedName(Result, S, &SS, !CurMethod);
828 // For unqualified lookup in a class template in MSVC mode, look into
829 // dependent base classes where the primary class template is known.
830 if (Result.empty() && SS.isEmpty() && getLangOpts().MSVCCompat) {
831 if (ParsedType TypeInBase =
832 recoverFromTypeInKnownDependentBase(*this, *Name, NameLoc))
836 // Perform lookup for Objective-C instance variables (including automatically
837 // synthesized instance variables), if we're in an Objective-C method.
838 // FIXME: This lookup really, really needs to be folded in to the normal
839 // unqualified lookup mechanism.
840 if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) {
841 ExprResult E = LookupInObjCMethod(Result, S, Name, true);
842 if (E.get() || E.isInvalid())
846 bool SecondTry = false;
847 bool IsFilteredTemplateName = false;
850 switch (Result.getResultKind()) {
851 case LookupResult::NotFound:
852 // If an unqualified-id is followed by a '(', then we have a function
854 if (!SS.isSet() && NextToken.is(tok::l_paren)) {
855 // In C++, this is an ADL-only call.
857 if (getLangOpts().CPlusPlus)
858 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true);
861 // If the expression that precedes the parenthesized argument list in a
862 // function call consists solely of an identifier, and if no
863 // declaration is visible for this identifier, the identifier is
864 // implicitly declared exactly as if, in the innermost block containing
865 // the function call, the declaration
867 // extern int identifier ();
871 // We also allow this in C99 as an extension.
872 if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) {
874 Result.resolveKind();
875 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false);
879 // In C, we first see whether there is a tag type by the same name, in
880 // which case it's likely that the user just forgot to write "enum",
881 // "struct", or "union".
882 if (!getLangOpts().CPlusPlus && !SecondTry &&
883 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
887 // Perform typo correction to determine if there is another name that is
888 // close to this name.
889 if (!SecondTry && CCC) {
891 if (TypoCorrection Corrected = CorrectTypo(Result.getLookupNameInfo(),
892 Result.getLookupKind(), S,
894 CTK_ErrorRecovery)) {
895 unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest;
896 unsigned QualifiedDiag = diag::err_no_member_suggest;
898 NamedDecl *FirstDecl = Corrected.getFoundDecl();
899 NamedDecl *UnderlyingFirstDecl = Corrected.getCorrectionDecl();
900 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
901 UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) {
902 UnqualifiedDiag = diag::err_no_template_suggest;
903 QualifiedDiag = diag::err_no_member_template_suggest;
904 } else if (UnderlyingFirstDecl &&
905 (isa<TypeDecl>(UnderlyingFirstDecl) ||
906 isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) ||
907 isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) {
908 UnqualifiedDiag = diag::err_unknown_typename_suggest;
909 QualifiedDiag = diag::err_unknown_nested_typename_suggest;
913 diagnoseTypo(Corrected, PDiag(UnqualifiedDiag) << Name);
914 } else {// FIXME: is this even reachable? Test it.
915 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
916 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
917 Name->getName().equals(CorrectedStr);
918 diagnoseTypo(Corrected, PDiag(QualifiedDiag)
919 << Name << computeDeclContext(SS, false)
920 << DroppedSpecifier << SS.getRange());
923 // Update the name, so that the caller has the new name.
924 Name = Corrected.getCorrectionAsIdentifierInfo();
926 // Typo correction corrected to a keyword.
927 if (Corrected.isKeyword())
930 // Also update the LookupResult...
931 // FIXME: This should probably go away at some point
933 Result.setLookupName(Corrected.getCorrection());
935 Result.addDecl(FirstDecl);
937 // If we found an Objective-C instance variable, let
938 // LookupInObjCMethod build the appropriate expression to
939 // reference the ivar.
940 // FIXME: This is a gross hack.
941 if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) {
943 ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier()));
951 // We failed to correct; just fall through and let the parser deal with it.
952 Result.suppressDiagnostics();
953 return NameClassification::Unknown();
955 case LookupResult::NotFoundInCurrentInstantiation: {
956 // We performed name lookup into the current instantiation, and there were
957 // dependent bases, so we treat this result the same way as any other
958 // dependent nested-name-specifier.
961 // A name used in a template declaration or definition and that is
962 // dependent on a template-parameter is assumed not to name a type
963 // unless the applicable name lookup finds a type name or the name is
964 // qualified by the keyword typename.
966 // FIXME: If the next token is '<', we might want to ask the parser to
967 // perform some heroics to see if we actually have a
968 // template-argument-list, which would indicate a missing 'template'
970 return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(),
971 NameInfo, IsAddressOfOperand,
972 /*TemplateArgs=*/nullptr);
975 case LookupResult::Found:
976 case LookupResult::FoundOverloaded:
977 case LookupResult::FoundUnresolvedValue:
980 case LookupResult::Ambiguous:
981 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
982 hasAnyAcceptableTemplateNames(Result)) {
983 // C++ [temp.local]p3:
984 // A lookup that finds an injected-class-name (10.2) can result in an
985 // ambiguity in certain cases (for example, if it is found in more than
986 // one base class). If all of the injected-class-names that are found
987 // refer to specializations of the same class template, and if the name
988 // is followed by a template-argument-list, the reference refers to the
989 // class template itself and not a specialization thereof, and is not
992 // This filtering can make an ambiguous result into an unambiguous one,
993 // so try again after filtering out template names.
994 FilterAcceptableTemplateNames(Result);
995 if (!Result.isAmbiguous()) {
996 IsFilteredTemplateName = true;
1001 // Diagnose the ambiguity and return an error.
1002 return NameClassification::Error();
1005 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
1006 (IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) {
1007 // C++ [temp.names]p3:
1008 // After name lookup (3.4) finds that a name is a template-name or that
1009 // an operator-function-id or a literal- operator-id refers to a set of
1010 // overloaded functions any member of which is a function template if
1011 // this is followed by a <, the < is always taken as the delimiter of a
1012 // template-argument-list and never as the less-than operator.
1013 if (!IsFilteredTemplateName)
1014 FilterAcceptableTemplateNames(Result);
1016 if (!Result.empty()) {
1017 bool IsFunctionTemplate;
1019 TemplateName Template;
1020 if (Result.end() - Result.begin() > 1) {
1021 IsFunctionTemplate = true;
1022 Template = Context.getOverloadedTemplateName(Result.begin(),
1026 = cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl());
1027 IsFunctionTemplate = isa<FunctionTemplateDecl>(TD);
1028 IsVarTemplate = isa<VarTemplateDecl>(TD);
1030 if (SS.isSet() && !SS.isInvalid())
1031 Template = Context.getQualifiedTemplateName(SS.getScopeRep(),
1032 /*TemplateKeyword=*/false,
1035 Template = TemplateName(TD);
1038 if (IsFunctionTemplate) {
1039 // Function templates always go through overload resolution, at which
1040 // point we'll perform the various checks (e.g., accessibility) we need
1041 // to based on which function we selected.
1042 Result.suppressDiagnostics();
1044 return NameClassification::FunctionTemplate(Template);
1047 return IsVarTemplate ? NameClassification::VarTemplate(Template)
1048 : NameClassification::TypeTemplate(Template);
1052 NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl();
1053 if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) {
1054 DiagnoseUseOfDecl(Type, NameLoc);
1055 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
1056 QualType T = Context.getTypeDeclType(Type);
1057 if (SS.isNotEmpty())
1058 return buildNestedType(*this, SS, T, NameLoc);
1059 return ParsedType::make(T);
1062 ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl);
1064 // FIXME: It's unfortunate that we don't have a Type node for handling this.
1065 if (ObjCCompatibleAliasDecl *Alias =
1066 dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl))
1067 Class = Alias->getClassInterface();
1071 DiagnoseUseOfDecl(Class, NameLoc);
1073 if (NextToken.is(tok::period)) {
1074 // Interface. <something> is parsed as a property reference expression.
1075 // Just return "unknown" as a fall-through for now.
1076 Result.suppressDiagnostics();
1077 return NameClassification::Unknown();
1080 QualType T = Context.getObjCInterfaceType(Class);
1081 return ParsedType::make(T);
1084 // We can have a type template here if we're classifying a template argument.
1085 if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl) &&
1086 !isa<VarTemplateDecl>(FirstDecl))
1087 return NameClassification::TypeTemplate(
1088 TemplateName(cast<TemplateDecl>(FirstDecl)));
1090 // Check for a tag type hidden by a non-type decl in a few cases where it
1091 // seems likely a type is wanted instead of the non-type that was found.
1092 bool NextIsOp = NextToken.isOneOf(tok::amp, tok::star);
1093 if ((NextToken.is(tok::identifier) ||
1095 FirstDecl->getUnderlyingDecl()->isFunctionOrFunctionTemplate())) &&
1096 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
1097 TypeDecl *Type = Result.getAsSingle<TypeDecl>();
1098 DiagnoseUseOfDecl(Type, NameLoc);
1099 QualType T = Context.getTypeDeclType(Type);
1100 if (SS.isNotEmpty())
1101 return buildNestedType(*this, SS, T, NameLoc);
1102 return ParsedType::make(T);
1105 if (FirstDecl->isCXXClassMember())
1106 return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result,
1109 bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren));
1110 return BuildDeclarationNameExpr(SS, Result, ADL);
1113 Sema::TemplateNameKindForDiagnostics
1114 Sema::getTemplateNameKindForDiagnostics(TemplateName Name) {
1115 auto *TD = Name.getAsTemplateDecl();
1117 return TemplateNameKindForDiagnostics::DependentTemplate;
1118 if (isa<ClassTemplateDecl>(TD))
1119 return TemplateNameKindForDiagnostics::ClassTemplate;
1120 if (isa<FunctionTemplateDecl>(TD))
1121 return TemplateNameKindForDiagnostics::FunctionTemplate;
1122 if (isa<VarTemplateDecl>(TD))
1123 return TemplateNameKindForDiagnostics::VarTemplate;
1124 if (isa<TypeAliasTemplateDecl>(TD))
1125 return TemplateNameKindForDiagnostics::AliasTemplate;
1126 if (isa<TemplateTemplateParmDecl>(TD))
1127 return TemplateNameKindForDiagnostics::TemplateTemplateParam;
1128 return TemplateNameKindForDiagnostics::DependentTemplate;
1131 // Determines the context to return to after temporarily entering a
1132 // context. This depends in an unnecessarily complicated way on the
1133 // exact ordering of callbacks from the parser.
1134 DeclContext *Sema::getContainingDC(DeclContext *DC) {
1136 // Functions defined inline within classes aren't parsed until we've
1137 // finished parsing the top-level class, so the top-level class is
1138 // the context we'll need to return to.
1139 // A Lambda call operator whose parent is a class must not be treated
1140 // as an inline member function. A Lambda can be used legally
1141 // either as an in-class member initializer or a default argument. These
1142 // are parsed once the class has been marked complete and so the containing
1143 // context would be the nested class (when the lambda is defined in one);
1144 // If the class is not complete, then the lambda is being used in an
1145 // ill-formed fashion (such as to specify the width of a bit-field, or
1146 // in an array-bound) - in which case we still want to return the
1147 // lexically containing DC (which could be a nested class).
1148 if (isa<FunctionDecl>(DC) && !isLambdaCallOperator(DC)) {
1149 DC = DC->getLexicalParent();
1151 // A function not defined within a class will always return to its
1153 if (!isa<CXXRecordDecl>(DC))
1156 // A C++ inline method/friend is parsed *after* the topmost class
1157 // it was declared in is fully parsed ("complete"); the topmost
1158 // class is the context we need to return to.
1159 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent()))
1162 // Return the declaration context of the topmost class the inline method is
1167 return DC->getLexicalParent();
1170 void Sema::PushDeclContext(Scope *S, DeclContext *DC) {
1171 assert(getContainingDC(DC) == CurContext &&
1172 "The next DeclContext should be lexically contained in the current one.");
1177 void Sema::PopDeclContext() {
1178 assert(CurContext && "DeclContext imbalance!");
1180 CurContext = getContainingDC(CurContext);
1181 assert(CurContext && "Popped translation unit!");
1184 Sema::SkippedDefinitionContext Sema::ActOnTagStartSkippedDefinition(Scope *S,
1186 // Unlike PushDeclContext, the context to which we return is not necessarily
1187 // the containing DC of TD, because the new context will be some pre-existing
1188 // TagDecl definition instead of a fresh one.
1189 auto Result = static_cast<SkippedDefinitionContext>(CurContext);
1190 CurContext = cast<TagDecl>(D)->getDefinition();
1191 assert(CurContext && "skipping definition of undefined tag");
1192 // Start lookups from the parent of the current context; we don't want to look
1193 // into the pre-existing complete definition.
1194 S->setEntity(CurContext->getLookupParent());
1198 void Sema::ActOnTagFinishSkippedDefinition(SkippedDefinitionContext Context) {
1199 CurContext = static_cast<decltype(CurContext)>(Context);
1202 /// EnterDeclaratorContext - Used when we must lookup names in the context
1203 /// of a declarator's nested name specifier.
1205 void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) {
1206 // C++0x [basic.lookup.unqual]p13:
1207 // A name used in the definition of a static data member of class
1208 // X (after the qualified-id of the static member) is looked up as
1209 // if the name was used in a member function of X.
1210 // C++0x [basic.lookup.unqual]p14:
1211 // If a variable member of a namespace is defined outside of the
1212 // scope of its namespace then any name used in the definition of
1213 // the variable member (after the declarator-id) is looked up as
1214 // if the definition of the variable member occurred in its
1216 // Both of these imply that we should push a scope whose context
1217 // is the semantic context of the declaration. We can't use
1218 // PushDeclContext here because that context is not necessarily
1219 // lexically contained in the current context. Fortunately,
1220 // the containing scope should have the appropriate information.
1222 assert(!S->getEntity() && "scope already has entity");
1225 Scope *Ancestor = S->getParent();
1226 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1227 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch");
1234 void Sema::ExitDeclaratorContext(Scope *S) {
1235 assert(S->getEntity() == CurContext && "Context imbalance!");
1237 // Switch back to the lexical context. The safety of this is
1238 // enforced by an assert in EnterDeclaratorContext.
1239 Scope *Ancestor = S->getParent();
1240 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1241 CurContext = Ancestor->getEntity();
1243 // We don't need to do anything with the scope, which is going to
1247 void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) {
1248 // We assume that the caller has already called
1249 // ActOnReenterTemplateScope so getTemplatedDecl() works.
1250 FunctionDecl *FD = D->getAsFunction();
1254 // Same implementation as PushDeclContext, but enters the context
1255 // from the lexical parent, rather than the top-level class.
1256 assert(CurContext == FD->getLexicalParent() &&
1257 "The next DeclContext should be lexically contained in the current one.");
1259 S->setEntity(CurContext);
1261 for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) {
1262 ParmVarDecl *Param = FD->getParamDecl(P);
1263 // If the parameter has an identifier, then add it to the scope
1264 if (Param->getIdentifier()) {
1266 IdResolver.AddDecl(Param);
1271 void Sema::ActOnExitFunctionContext() {
1272 // Same implementation as PopDeclContext, but returns to the lexical parent,
1273 // rather than the top-level class.
1274 assert(CurContext && "DeclContext imbalance!");
1275 CurContext = CurContext->getLexicalParent();
1276 assert(CurContext && "Popped translation unit!");
1279 /// \brief Determine whether we allow overloading of the function
1280 /// PrevDecl with another declaration.
1282 /// This routine determines whether overloading is possible, not
1283 /// whether some new function is actually an overload. It will return
1284 /// true in C++ (where we can always provide overloads) or, as an
1285 /// extension, in C when the previous function is already an
1286 /// overloaded function declaration or has the "overloadable"
1288 static bool AllowOverloadingOfFunction(LookupResult &Previous,
1289 ASTContext &Context) {
1290 if (Context.getLangOpts().CPlusPlus)
1293 if (Previous.getResultKind() == LookupResult::FoundOverloaded)
1296 return (Previous.getResultKind() == LookupResult::Found
1297 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>());
1300 /// Add this decl to the scope shadowed decl chains.
1301 void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) {
1302 // Move up the scope chain until we find the nearest enclosing
1303 // non-transparent context. The declaration will be introduced into this
1305 while (S->getEntity() && S->getEntity()->isTransparentContext())
1308 // Add scoped declarations into their context, so that they can be
1309 // found later. Declarations without a context won't be inserted
1310 // into any context.
1312 CurContext->addDecl(D);
1314 // Out-of-line definitions shouldn't be pushed into scope in C++, unless they
1315 // are function-local declarations.
1316 if (getLangOpts().CPlusPlus && D->isOutOfLine() &&
1317 !D->getDeclContext()->getRedeclContext()->Equals(
1318 D->getLexicalDeclContext()->getRedeclContext()) &&
1319 !D->getLexicalDeclContext()->isFunctionOrMethod())
1322 // Template instantiations should also not be pushed into scope.
1323 if (isa<FunctionDecl>(D) &&
1324 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization())
1327 // If this replaces anything in the current scope,
1328 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()),
1329 IEnd = IdResolver.end();
1330 for (; I != IEnd; ++I) {
1331 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) {
1333 IdResolver.RemoveDecl(*I);
1335 // Should only need to replace one decl.
1342 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) {
1343 // Implicitly-generated labels may end up getting generated in an order that
1344 // isn't strictly lexical, which breaks name lookup. Be careful to insert
1345 // the label at the appropriate place in the identifier chain.
1346 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) {
1347 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext();
1348 if (IDC == CurContext) {
1349 if (!S->isDeclScope(*I))
1351 } else if (IDC->Encloses(CurContext))
1355 IdResolver.InsertDeclAfter(I, D);
1357 IdResolver.AddDecl(D);
1361 void Sema::pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name) {
1362 if (IdResolver.tryAddTopLevelDecl(D, Name) && TUScope)
1363 TUScope->AddDecl(D);
1366 bool Sema::isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S,
1367 bool AllowInlineNamespace) {
1368 return IdResolver.isDeclInScope(D, Ctx, S, AllowInlineNamespace);
1371 Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) {
1372 DeclContext *TargetDC = DC->getPrimaryContext();
1374 if (DeclContext *ScopeDC = S->getEntity())
1375 if (ScopeDC->getPrimaryContext() == TargetDC)
1377 } while ((S = S->getParent()));
1382 static bool isOutOfScopePreviousDeclaration(NamedDecl *,
1386 /// Filters out lookup results that don't fall within the given scope
1387 /// as determined by isDeclInScope.
1388 void Sema::FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S,
1389 bool ConsiderLinkage,
1390 bool AllowInlineNamespace) {
1391 LookupResult::Filter F = R.makeFilter();
1392 while (F.hasNext()) {
1393 NamedDecl *D = F.next();
1395 if (isDeclInScope(D, Ctx, S, AllowInlineNamespace))
1398 if (ConsiderLinkage && isOutOfScopePreviousDeclaration(D, Ctx, Context))
1407 static bool isUsingDecl(NamedDecl *D) {
1408 return isa<UsingShadowDecl>(D) ||
1409 isa<UnresolvedUsingTypenameDecl>(D) ||
1410 isa<UnresolvedUsingValueDecl>(D);
1413 /// Removes using shadow declarations from the lookup results.
1414 static void RemoveUsingDecls(LookupResult &R) {
1415 LookupResult::Filter F = R.makeFilter();
1417 if (isUsingDecl(F.next()))
1423 /// \brief Check for this common pattern:
1426 /// S(const S&); // DO NOT IMPLEMENT
1427 /// void operator=(const S&); // DO NOT IMPLEMENT
1430 static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) {
1431 // FIXME: Should check for private access too but access is set after we get
1433 if (D->doesThisDeclarationHaveABody())
1436 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D))
1437 return CD->isCopyConstructor();
1438 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
1439 return Method->isCopyAssignmentOperator();
1443 // We need this to handle
1446 // void *foo() { return 0; }
1449 // When we see foo we don't know if after the typedef we will get 'A' or '*A'
1450 // for example. If 'A', foo will have external linkage. If we have '*A',
1451 // foo will have no linkage. Since we can't know until we get to the end
1452 // of the typedef, this function finds out if D might have non-external linkage.
1453 // Callers should verify at the end of the TU if it D has external linkage or
1455 bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) {
1456 const DeclContext *DC = D->getDeclContext();
1457 while (!DC->isTranslationUnit()) {
1458 if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){
1459 if (!RD->hasNameForLinkage())
1462 DC = DC->getParent();
1465 return !D->isExternallyVisible();
1468 // FIXME: This needs to be refactored; some other isInMainFile users want
1470 static bool isMainFileLoc(const Sema &S, SourceLocation Loc) {
1471 if (S.TUKind != TU_Complete)
1473 return S.SourceMgr.isInMainFile(Loc);
1476 bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
1479 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>())
1482 // Ignore all entities declared within templates, and out-of-line definitions
1483 // of members of class templates.
1484 if (D->getDeclContext()->isDependentContext() ||
1485 D->getLexicalDeclContext()->isDependentContext())
1488 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1489 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1492 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
1493 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD))
1496 // 'static inline' functions are defined in headers; don't warn.
1497 if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation()))
1501 if (FD->doesThisDeclarationHaveABody() &&
1502 Context.DeclMustBeEmitted(FD))
1504 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1505 // Constants and utility variables are defined in headers with internal
1506 // linkage; don't warn. (Unlike functions, there isn't a convenient marker
1508 if (!isMainFileLoc(*this, VD->getLocation()))
1511 if (Context.DeclMustBeEmitted(VD))
1514 if (VD->isStaticDataMember() &&
1515 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1518 if (VD->isInline() && !isMainFileLoc(*this, VD->getLocation()))
1524 // Only warn for unused decls internal to the translation unit.
1525 // FIXME: This seems like a bogus check; it suppresses -Wunused-function
1526 // for inline functions defined in the main source file, for instance.
1527 return mightHaveNonExternalLinkage(D);
1530 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
1534 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1535 const FunctionDecl *First = FD->getFirstDecl();
1536 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1537 return; // First should already be in the vector.
1540 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1541 const VarDecl *First = VD->getFirstDecl();
1542 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1543 return; // First should already be in the vector.
1546 if (ShouldWarnIfUnusedFileScopedDecl(D))
1547 UnusedFileScopedDecls.push_back(D);
1550 static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
1551 if (D->isInvalidDecl())
1554 if (D->isReferenced() || D->isUsed() || D->hasAttr<UnusedAttr>() ||
1555 D->hasAttr<ObjCPreciseLifetimeAttr>())
1558 if (isa<LabelDecl>(D))
1561 // Except for labels, we only care about unused decls that are local to
1563 bool WithinFunction = D->getDeclContext()->isFunctionOrMethod();
1564 if (const auto *R = dyn_cast<CXXRecordDecl>(D->getDeclContext()))
1565 // For dependent types, the diagnostic is deferred.
1567 WithinFunction || (R->isLocalClass() && !R->isDependentType());
1568 if (!WithinFunction)
1571 if (isa<TypedefNameDecl>(D))
1574 // White-list anything that isn't a local variable.
1575 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D))
1578 // Types of valid local variables should be complete, so this should succeed.
1579 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1581 // White-list anything with an __attribute__((unused)) type.
1582 const auto *Ty = VD->getType().getTypePtr();
1584 // Only look at the outermost level of typedef.
1585 if (const TypedefType *TT = Ty->getAs<TypedefType>()) {
1586 if (TT->getDecl()->hasAttr<UnusedAttr>())
1590 // If we failed to complete the type for some reason, or if the type is
1591 // dependent, don't diagnose the variable.
1592 if (Ty->isIncompleteType() || Ty->isDependentType())
1595 // Look at the element type to ensure that the warning behaviour is
1596 // consistent for both scalars and arrays.
1597 Ty = Ty->getBaseElementTypeUnsafe();
1599 if (const TagType *TT = Ty->getAs<TagType>()) {
1600 const TagDecl *Tag = TT->getDecl();
1601 if (Tag->hasAttr<UnusedAttr>())
1604 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) {
1605 if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>())
1608 if (const Expr *Init = VD->getInit()) {
1609 if (const ExprWithCleanups *Cleanups =
1610 dyn_cast<ExprWithCleanups>(Init))
1611 Init = Cleanups->getSubExpr();
1612 const CXXConstructExpr *Construct =
1613 dyn_cast<CXXConstructExpr>(Init);
1614 if (Construct && !Construct->isElidable()) {
1615 CXXConstructorDecl *CD = Construct->getConstructor();
1616 if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>())
1623 // TODO: __attribute__((unused)) templates?
1629 static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx,
1631 if (isa<LabelDecl>(D)) {
1632 SourceLocation AfterColon = Lexer::findLocationAfterToken(D->getLocEnd(),
1633 tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(), true);
1634 if (AfterColon.isInvalid())
1636 Hint = FixItHint::CreateRemoval(CharSourceRange::
1637 getCharRange(D->getLocStart(), AfterColon));
1641 void Sema::DiagnoseUnusedNestedTypedefs(const RecordDecl *D) {
1642 if (D->getTypeForDecl()->isDependentType())
1645 for (auto *TmpD : D->decls()) {
1646 if (const auto *T = dyn_cast<TypedefNameDecl>(TmpD))
1647 DiagnoseUnusedDecl(T);
1648 else if(const auto *R = dyn_cast<RecordDecl>(TmpD))
1649 DiagnoseUnusedNestedTypedefs(R);
1653 /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used
1654 /// unless they are marked attr(unused).
1655 void Sema::DiagnoseUnusedDecl(const NamedDecl *D) {
1656 if (!ShouldDiagnoseUnusedDecl(D))
1659 if (auto *TD = dyn_cast<TypedefNameDecl>(D)) {
1660 // typedefs can be referenced later on, so the diagnostics are emitted
1661 // at end-of-translation-unit.
1662 UnusedLocalTypedefNameCandidates.insert(TD);
1667 GenerateFixForUnusedDecl(D, Context, Hint);
1670 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable())
1671 DiagID = diag::warn_unused_exception_param;
1672 else if (isa<LabelDecl>(D))
1673 DiagID = diag::warn_unused_label;
1675 DiagID = diag::warn_unused_variable;
1677 Diag(D->getLocation(), DiagID) << D->getDeclName() << Hint;
1680 static void CheckPoppedLabel(LabelDecl *L, Sema &S) {
1681 // Verify that we have no forward references left. If so, there was a goto
1682 // or address of a label taken, but no definition of it. Label fwd
1683 // definitions are indicated with a null substmt which is also not a resolved
1684 // MS inline assembly label name.
1685 bool Diagnose = false;
1686 if (L->isMSAsmLabel())
1687 Diagnose = !L->isResolvedMSAsmLabel();
1689 Diagnose = L->getStmt() == nullptr;
1691 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName();
1694 void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) {
1695 S->mergeNRVOIntoParent();
1697 if (S->decl_empty()) return;
1698 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) &&
1699 "Scope shouldn't contain decls!");
1701 for (auto *TmpD : S->decls()) {
1702 assert(TmpD && "This decl didn't get pushed??");
1704 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?");
1705 NamedDecl *D = cast<NamedDecl>(TmpD);
1707 if (!D->getDeclName()) continue;
1709 // Diagnose unused variables in this scope.
1710 if (!S->hasUnrecoverableErrorOccurred()) {
1711 DiagnoseUnusedDecl(D);
1712 if (const auto *RD = dyn_cast<RecordDecl>(D))
1713 DiagnoseUnusedNestedTypedefs(RD);
1716 // If this was a forward reference to a label, verify it was defined.
1717 if (LabelDecl *LD = dyn_cast<LabelDecl>(D))
1718 CheckPoppedLabel(LD, *this);
1720 // Remove this name from our lexical scope, and warn on it if we haven't
1722 IdResolver.RemoveDecl(D);
1723 auto ShadowI = ShadowingDecls.find(D);
1724 if (ShadowI != ShadowingDecls.end()) {
1725 if (const auto *FD = dyn_cast<FieldDecl>(ShadowI->second)) {
1726 Diag(D->getLocation(), diag::warn_ctor_parm_shadows_field)
1727 << D << FD << FD->getParent();
1728 Diag(FD->getLocation(), diag::note_previous_declaration);
1730 ShadowingDecls.erase(ShadowI);
1735 /// \brief Look for an Objective-C class in the translation unit.
1737 /// \param Id The name of the Objective-C class we're looking for. If
1738 /// typo-correction fixes this name, the Id will be updated
1739 /// to the fixed name.
1741 /// \param IdLoc The location of the name in the translation unit.
1743 /// \param DoTypoCorrection If true, this routine will attempt typo correction
1744 /// if there is no class with the given name.
1746 /// \returns The declaration of the named Objective-C class, or NULL if the
1747 /// class could not be found.
1748 ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id,
1749 SourceLocation IdLoc,
1750 bool DoTypoCorrection) {
1751 // The third "scope" argument is 0 since we aren't enabling lazy built-in
1752 // creation from this context.
1753 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName);
1755 if (!IDecl && DoTypoCorrection) {
1756 // Perform typo correction at the given location, but only if we
1757 // find an Objective-C class name.
1758 if (TypoCorrection C = CorrectTypo(
1759 DeclarationNameInfo(Id, IdLoc), LookupOrdinaryName, TUScope, nullptr,
1760 llvm::make_unique<DeclFilterCCC<ObjCInterfaceDecl>>(),
1761 CTK_ErrorRecovery)) {
1762 diagnoseTypo(C, PDiag(diag::err_undef_interface_suggest) << Id);
1763 IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>();
1764 Id = IDecl->getIdentifier();
1767 ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl);
1768 // This routine must always return a class definition, if any.
1769 if (Def && Def->getDefinition())
1770 Def = Def->getDefinition();
1774 /// getNonFieldDeclScope - Retrieves the innermost scope, starting
1775 /// from S, where a non-field would be declared. This routine copes
1776 /// with the difference between C and C++ scoping rules in structs and
1777 /// unions. For example, the following code is well-formed in C but
1778 /// ill-formed in C++:
1784 /// void test_S6() {
1789 /// For the declaration of BAR, this routine will return a different
1790 /// scope. The scope S will be the scope of the unnamed enumeration
1791 /// within S6. In C++, this routine will return the scope associated
1792 /// with S6, because the enumeration's scope is a transparent
1793 /// context but structures can contain non-field names. In C, this
1794 /// routine will return the translation unit scope, since the
1795 /// enumeration's scope is a transparent context and structures cannot
1796 /// contain non-field names.
1797 Scope *Sema::getNonFieldDeclScope(Scope *S) {
1798 while (((S->getFlags() & Scope::DeclScope) == 0) ||
1799 (S->getEntity() && S->getEntity()->isTransparentContext()) ||
1800 (S->isClassScope() && !getLangOpts().CPlusPlus))
1805 /// \brief Looks up the declaration of "struct objc_super" and
1806 /// saves it for later use in building builtin declaration of
1807 /// objc_msgSendSuper and objc_msgSendSuper_stret. If no such
1808 /// pre-existing declaration exists no action takes place.
1809 static void LookupPredefedObjCSuperType(Sema &ThisSema, Scope *S,
1810 IdentifierInfo *II) {
1811 if (!II->isStr("objc_msgSendSuper"))
1813 ASTContext &Context = ThisSema.Context;
1815 LookupResult Result(ThisSema, &Context.Idents.get("objc_super"),
1816 SourceLocation(), Sema::LookupTagName);
1817 ThisSema.LookupName(Result, S);
1818 if (Result.getResultKind() == LookupResult::Found)
1819 if (const TagDecl *TD = Result.getAsSingle<TagDecl>())
1820 Context.setObjCSuperType(Context.getTagDeclType(TD));
1823 static StringRef getHeaderName(ASTContext::GetBuiltinTypeError Error) {
1825 case ASTContext::GE_None:
1827 case ASTContext::GE_Missing_stdio:
1829 case ASTContext::GE_Missing_setjmp:
1831 case ASTContext::GE_Missing_ucontext:
1832 return "ucontext.h";
1834 llvm_unreachable("unhandled error kind");
1837 /// LazilyCreateBuiltin - The specified Builtin-ID was first used at
1838 /// file scope. lazily create a decl for it. ForRedeclaration is true
1839 /// if we're creating this built-in in anticipation of redeclaring the
1841 NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID,
1842 Scope *S, bool ForRedeclaration,
1843 SourceLocation Loc) {
1844 LookupPredefedObjCSuperType(*this, S, II);
1846 ASTContext::GetBuiltinTypeError Error;
1847 QualType R = Context.GetBuiltinType(ID, Error);
1849 if (ForRedeclaration)
1850 Diag(Loc, diag::warn_implicit_decl_requires_sysheader)
1851 << getHeaderName(Error) << Context.BuiltinInfo.getName(ID);
1855 if (!ForRedeclaration &&
1856 (Context.BuiltinInfo.isPredefinedLibFunction(ID) ||
1857 Context.BuiltinInfo.isHeaderDependentFunction(ID))) {
1858 Diag(Loc, diag::ext_implicit_lib_function_decl)
1859 << Context.BuiltinInfo.getName(ID) << R;
1860 if (Context.BuiltinInfo.getHeaderName(ID) &&
1861 !Diags.isIgnored(diag::ext_implicit_lib_function_decl, Loc))
1862 Diag(Loc, diag::note_include_header_or_declare)
1863 << Context.BuiltinInfo.getHeaderName(ID)
1864 << Context.BuiltinInfo.getName(ID);
1870 DeclContext *Parent = Context.getTranslationUnitDecl();
1871 if (getLangOpts().CPlusPlus) {
1872 LinkageSpecDecl *CLinkageDecl =
1873 LinkageSpecDecl::Create(Context, Parent, Loc, Loc,
1874 LinkageSpecDecl::lang_c, false);
1875 CLinkageDecl->setImplicit();
1876 Parent->addDecl(CLinkageDecl);
1877 Parent = CLinkageDecl;
1880 FunctionDecl *New = FunctionDecl::Create(Context,
1882 Loc, Loc, II, R, /*TInfo=*/nullptr,
1885 R->isFunctionProtoType());
1888 // Create Decl objects for each parameter, adding them to the
1890 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) {
1891 SmallVector<ParmVarDecl*, 16> Params;
1892 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
1894 ParmVarDecl::Create(Context, New, SourceLocation(), SourceLocation(),
1895 nullptr, FT->getParamType(i), /*TInfo=*/nullptr,
1897 parm->setScopeInfo(0, i);
1898 Params.push_back(parm);
1900 New->setParams(Params);
1903 AddKnownFunctionAttributes(New);
1904 RegisterLocallyScopedExternCDecl(New, S);
1906 // TUScope is the translation-unit scope to insert this function into.
1907 // FIXME: This is hideous. We need to teach PushOnScopeChains to
1908 // relate Scopes to DeclContexts, and probably eliminate CurContext
1909 // entirely, but we're not there yet.
1910 DeclContext *SavedContext = CurContext;
1911 CurContext = Parent;
1912 PushOnScopeChains(New, TUScope);
1913 CurContext = SavedContext;
1917 /// Typedef declarations don't have linkage, but they still denote the same
1918 /// entity if their types are the same.
1919 /// FIXME: This is notionally doing the same thing as ASTReaderDecl's
1921 static void filterNonConflictingPreviousTypedefDecls(Sema &S,
1922 TypedefNameDecl *Decl,
1923 LookupResult &Previous) {
1924 // This is only interesting when modules are enabled.
1925 if (!S.getLangOpts().Modules && !S.getLangOpts().ModulesLocalVisibility)
1928 // Empty sets are uninteresting.
1929 if (Previous.empty())
1932 LookupResult::Filter Filter = Previous.makeFilter();
1933 while (Filter.hasNext()) {
1934 NamedDecl *Old = Filter.next();
1936 // Non-hidden declarations are never ignored.
1937 if (S.isVisible(Old))
1940 // Declarations of the same entity are not ignored, even if they have
1941 // different linkages.
1942 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
1943 if (S.Context.hasSameType(OldTD->getUnderlyingType(),
1944 Decl->getUnderlyingType()))
1947 // If both declarations give a tag declaration a typedef name for linkage
1948 // purposes, then they declare the same entity.
1949 if (S.getLangOpts().CPlusPlus &&
1950 OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true) &&
1951 Decl->getAnonDeclWithTypedefName())
1961 bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) {
1963 if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old))
1964 OldType = OldTypedef->getUnderlyingType();
1966 OldType = Context.getTypeDeclType(Old);
1967 QualType NewType = New->getUnderlyingType();
1969 if (NewType->isVariablyModifiedType()) {
1970 // Must not redefine a typedef with a variably-modified type.
1971 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1972 Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef)
1974 if (Old->getLocation().isValid())
1975 Diag(Old->getLocation(), diag::note_previous_definition);
1976 New->setInvalidDecl();
1980 if (OldType != NewType &&
1981 !OldType->isDependentType() &&
1982 !NewType->isDependentType() &&
1983 !Context.hasSameType(OldType, NewType)) {
1984 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1985 Diag(New->getLocation(), diag::err_redefinition_different_typedef)
1986 << Kind << NewType << OldType;
1987 if (Old->getLocation().isValid())
1988 Diag(Old->getLocation(), diag::note_previous_definition);
1989 New->setInvalidDecl();
1995 /// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the
1996 /// same name and scope as a previous declaration 'Old'. Figure out
1997 /// how to resolve this situation, merging decls or emitting
1998 /// diagnostics as appropriate. If there was an error, set New to be invalid.
2000 void Sema::MergeTypedefNameDecl(Scope *S, TypedefNameDecl *New,
2001 LookupResult &OldDecls) {
2002 // If the new decl is known invalid already, don't bother doing any
2004 if (New->isInvalidDecl()) return;
2006 // Allow multiple definitions for ObjC built-in typedefs.
2007 // FIXME: Verify the underlying types are equivalent!
2008 if (getLangOpts().ObjC1) {
2009 const IdentifierInfo *TypeID = New->getIdentifier();
2010 switch (TypeID->getLength()) {
2014 if (!TypeID->isStr("id"))
2016 QualType T = New->getUnderlyingType();
2017 if (!T->isPointerType())
2019 if (!T->isVoidPointerType()) {
2020 QualType PT = T->getAs<PointerType>()->getPointeeType();
2021 if (!PT->isStructureType())
2024 Context.setObjCIdRedefinitionType(T);
2025 // Install the built-in type for 'id', ignoring the current definition.
2026 New->setTypeForDecl(Context.getObjCIdType().getTypePtr());
2030 if (!TypeID->isStr("Class"))
2032 Context.setObjCClassRedefinitionType(New->getUnderlyingType());
2033 // Install the built-in type for 'Class', ignoring the current definition.
2034 New->setTypeForDecl(Context.getObjCClassType().getTypePtr());
2037 if (!TypeID->isStr("SEL"))
2039 Context.setObjCSelRedefinitionType(New->getUnderlyingType());
2040 // Install the built-in type for 'SEL', ignoring the current definition.
2041 New->setTypeForDecl(Context.getObjCSelType().getTypePtr());
2044 // Fall through - the typedef name was not a builtin type.
2047 // Verify the old decl was also a type.
2048 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>();
2050 Diag(New->getLocation(), diag::err_redefinition_different_kind)
2051 << New->getDeclName();
2053 NamedDecl *OldD = OldDecls.getRepresentativeDecl();
2054 if (OldD->getLocation().isValid())
2055 Diag(OldD->getLocation(), diag::note_previous_definition);
2057 return New->setInvalidDecl();
2060 // If the old declaration is invalid, just give up here.
2061 if (Old->isInvalidDecl())
2062 return New->setInvalidDecl();
2064 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
2065 auto *OldTag = OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true);
2066 auto *NewTag = New->getAnonDeclWithTypedefName();
2067 NamedDecl *Hidden = nullptr;
2068 if (getLangOpts().CPlusPlus && OldTag && NewTag &&
2069 OldTag->getCanonicalDecl() != NewTag->getCanonicalDecl() &&
2070 !hasVisibleDefinition(OldTag, &Hidden)) {
2071 // There is a definition of this tag, but it is not visible. Use it
2072 // instead of our tag.
2073 New->setTypeForDecl(OldTD->getTypeForDecl());
2074 if (OldTD->isModed())
2075 New->setModedTypeSourceInfo(OldTD->getTypeSourceInfo(),
2076 OldTD->getUnderlyingType());
2078 New->setTypeSourceInfo(OldTD->getTypeSourceInfo());
2080 // Make the old tag definition visible.
2081 makeMergedDefinitionVisible(Hidden, NewTag->getLocation());
2083 // If this was an unscoped enumeration, yank all of its enumerators
2084 // out of the scope.
2085 if (isa<EnumDecl>(NewTag)) {
2086 Scope *EnumScope = getNonFieldDeclScope(S);
2087 for (auto *D : NewTag->decls()) {
2088 auto *ED = cast<EnumConstantDecl>(D);
2089 assert(EnumScope->isDeclScope(ED));
2090 EnumScope->RemoveDecl(ED);
2091 IdResolver.RemoveDecl(ED);
2092 ED->getLexicalDeclContext()->removeDecl(ED);
2098 // If the typedef types are not identical, reject them in all languages and
2099 // with any extensions enabled.
2100 if (isIncompatibleTypedef(Old, New))
2103 // The types match. Link up the redeclaration chain and merge attributes if
2104 // the old declaration was a typedef.
2105 if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) {
2106 New->setPreviousDecl(Typedef);
2107 mergeDeclAttributes(New, Old);
2110 if (getLangOpts().MicrosoftExt)
2113 if (getLangOpts().CPlusPlus) {
2114 // C++ [dcl.typedef]p2:
2115 // In a given non-class scope, a typedef specifier can be used to
2116 // redefine the name of any type declared in that scope to refer
2117 // to the type to which it already refers.
2118 if (!isa<CXXRecordDecl>(CurContext))
2121 // C++0x [dcl.typedef]p4:
2122 // In a given class scope, a typedef specifier can be used to redefine
2123 // any class-name declared in that scope that is not also a typedef-name
2124 // to refer to the type to which it already refers.
2126 // This wording came in via DR424, which was a correction to the
2127 // wording in DR56, which accidentally banned code like:
2130 // typedef struct A { } A;
2133 // in the C++03 standard. We implement the C++0x semantics, which
2134 // allow the above but disallow
2141 // since that was the intent of DR56.
2142 if (!isa<TypedefNameDecl>(Old))
2145 Diag(New->getLocation(), diag::err_redefinition)
2146 << New->getDeclName();
2147 Diag(Old->getLocation(), diag::note_previous_definition);
2148 return New->setInvalidDecl();
2151 // Modules always permit redefinition of typedefs, as does C11.
2152 if (getLangOpts().Modules || getLangOpts().C11)
2155 // If we have a redefinition of a typedef in C, emit a warning. This warning
2156 // is normally mapped to an error, but can be controlled with
2157 // -Wtypedef-redefinition. If either the original or the redefinition is
2158 // in a system header, don't emit this for compatibility with GCC.
2159 if (getDiagnostics().getSuppressSystemWarnings() &&
2160 // Some standard types are defined implicitly in Clang (e.g. OpenCL).
2161 (Old->isImplicit() ||
2162 Context.getSourceManager().isInSystemHeader(Old->getLocation()) ||
2163 Context.getSourceManager().isInSystemHeader(New->getLocation())))
2166 Diag(New->getLocation(), diag::ext_redefinition_of_typedef)
2167 << New->getDeclName();
2168 Diag(Old->getLocation(), diag::note_previous_definition);
2171 /// DeclhasAttr - returns true if decl Declaration already has the target
2173 static bool DeclHasAttr(const Decl *D, const Attr *A) {
2174 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A);
2175 const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A);
2176 for (const auto *i : D->attrs())
2177 if (i->getKind() == A->getKind()) {
2179 if (Ann->getAnnotation() == cast<AnnotateAttr>(i)->getAnnotation())
2183 // FIXME: Don't hardcode this check
2184 if (OA && isa<OwnershipAttr>(i))
2185 return OA->getOwnKind() == cast<OwnershipAttr>(i)->getOwnKind();
2192 static bool isAttributeTargetADefinition(Decl *D) {
2193 if (VarDecl *VD = dyn_cast<VarDecl>(D))
2194 return VD->isThisDeclarationADefinition();
2195 if (TagDecl *TD = dyn_cast<TagDecl>(D))
2196 return TD->isCompleteDefinition() || TD->isBeingDefined();
2200 /// Merge alignment attributes from \p Old to \p New, taking into account the
2201 /// special semantics of C11's _Alignas specifier and C++11's alignas attribute.
2203 /// \return \c true if any attributes were added to \p New.
2204 static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) {
2205 // Look for alignas attributes on Old, and pick out whichever attribute
2206 // specifies the strictest alignment requirement.
2207 AlignedAttr *OldAlignasAttr = nullptr;
2208 AlignedAttr *OldStrictestAlignAttr = nullptr;
2209 unsigned OldAlign = 0;
2210 for (auto *I : Old->specific_attrs<AlignedAttr>()) {
2211 // FIXME: We have no way of representing inherited dependent alignments
2213 // template<int A, int B> struct alignas(A) X;
2214 // template<int A, int B> struct alignas(B) X {};
2215 // For now, we just ignore any alignas attributes which are not on the
2216 // definition in such a case.
2217 if (I->isAlignmentDependent())
2223 unsigned Align = I->getAlignment(S.Context);
2224 if (Align > OldAlign) {
2226 OldStrictestAlignAttr = I;
2230 // Look for alignas attributes on New.
2231 AlignedAttr *NewAlignasAttr = nullptr;
2232 unsigned NewAlign = 0;
2233 for (auto *I : New->specific_attrs<AlignedAttr>()) {
2234 if (I->isAlignmentDependent())
2240 unsigned Align = I->getAlignment(S.Context);
2241 if (Align > NewAlign)
2245 if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) {
2246 // Both declarations have 'alignas' attributes. We require them to match.
2247 // C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but
2248 // fall short. (If two declarations both have alignas, they must both match
2249 // every definition, and so must match each other if there is a definition.)
2251 // If either declaration only contains 'alignas(0)' specifiers, then it
2252 // specifies the natural alignment for the type.
2253 if (OldAlign == 0 || NewAlign == 0) {
2255 if (ValueDecl *VD = dyn_cast<ValueDecl>(New))
2258 Ty = S.Context.getTagDeclType(cast<TagDecl>(New));
2261 OldAlign = S.Context.getTypeAlign(Ty);
2263 NewAlign = S.Context.getTypeAlign(Ty);
2266 if (OldAlign != NewAlign) {
2267 S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch)
2268 << (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity()
2269 << (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity();
2270 S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration);
2274 if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) {
2275 // C++11 [dcl.align]p6:
2276 // if any declaration of an entity has an alignment-specifier,
2277 // every defining declaration of that entity shall specify an
2278 // equivalent alignment.
2280 // If the definition of an object does not have an alignment
2281 // specifier, any other declaration of that object shall also
2282 // have no alignment specifier.
2283 S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition)
2285 S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration)
2289 bool AnyAdded = false;
2291 // Ensure we have an attribute representing the strictest alignment.
2292 if (OldAlign > NewAlign) {
2293 AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context);
2294 Clone->setInherited(true);
2295 New->addAttr(Clone);
2299 // Ensure we have an alignas attribute if the old declaration had one.
2300 if (OldAlignasAttr && !NewAlignasAttr &&
2301 !(AnyAdded && OldStrictestAlignAttr->isAlignas())) {
2302 AlignedAttr *Clone = OldAlignasAttr->clone(S.Context);
2303 Clone->setInherited(true);
2304 New->addAttr(Clone);
2311 static bool mergeDeclAttribute(Sema &S, NamedDecl *D,
2312 const InheritableAttr *Attr,
2313 Sema::AvailabilityMergeKind AMK) {
2314 // This function copies an attribute Attr from a previous declaration to the
2315 // new declaration D if the new declaration doesn't itself have that attribute
2316 // yet or if that attribute allows duplicates.
2317 // If you're adding a new attribute that requires logic different from
2318 // "use explicit attribute on decl if present, else use attribute from
2319 // previous decl", for example if the attribute needs to be consistent
2320 // between redeclarations, you need to call a custom merge function here.
2321 InheritableAttr *NewAttr = nullptr;
2322 unsigned AttrSpellingListIndex = Attr->getSpellingListIndex();
2323 if (const auto *AA = dyn_cast<AvailabilityAttr>(Attr))
2324 NewAttr = S.mergeAvailabilityAttr(D, AA->getRange(), AA->getPlatform(),
2325 AA->isImplicit(), AA->getIntroduced(),
2326 AA->getDeprecated(),
2327 AA->getObsoleted(), AA->getUnavailable(),
2328 AA->getMessage(), AA->getStrict(),
2329 AA->getReplacement(), AMK,
2330 AttrSpellingListIndex);
2331 else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr))
2332 NewAttr = S.mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2333 AttrSpellingListIndex);
2334 else if (const auto *VA = dyn_cast<TypeVisibilityAttr>(Attr))
2335 NewAttr = S.mergeTypeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2336 AttrSpellingListIndex);
2337 else if (const auto *ImportA = dyn_cast<DLLImportAttr>(Attr))
2338 NewAttr = S.mergeDLLImportAttr(D, ImportA->getRange(),
2339 AttrSpellingListIndex);
2340 else if (const auto *ExportA = dyn_cast<DLLExportAttr>(Attr))
2341 NewAttr = S.mergeDLLExportAttr(D, ExportA->getRange(),
2342 AttrSpellingListIndex);
2343 else if (const auto *FA = dyn_cast<FormatAttr>(Attr))
2344 NewAttr = S.mergeFormatAttr(D, FA->getRange(), FA->getType(),
2345 FA->getFormatIdx(), FA->getFirstArg(),
2346 AttrSpellingListIndex);
2347 else if (const auto *SA = dyn_cast<SectionAttr>(Attr))
2348 NewAttr = S.mergeSectionAttr(D, SA->getRange(), SA->getName(),
2349 AttrSpellingListIndex);
2350 else if (const auto *IA = dyn_cast<MSInheritanceAttr>(Attr))
2351 NewAttr = S.mergeMSInheritanceAttr(D, IA->getRange(), IA->getBestCase(),
2352 AttrSpellingListIndex,
2353 IA->getSemanticSpelling());
2354 else if (const auto *AA = dyn_cast<AlwaysInlineAttr>(Attr))
2355 NewAttr = S.mergeAlwaysInlineAttr(D, AA->getRange(),
2356 &S.Context.Idents.get(AA->getSpelling()),
2357 AttrSpellingListIndex);
2358 else if (S.getLangOpts().CUDA && isa<FunctionDecl>(D) &&
2359 (isa<CUDAHostAttr>(Attr) || isa<CUDADeviceAttr>(Attr) ||
2360 isa<CUDAGlobalAttr>(Attr))) {
2361 // CUDA target attributes are part of function signature for
2362 // overloading purposes and must not be merged.
2364 } else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr))
2365 NewAttr = S.mergeMinSizeAttr(D, MA->getRange(), AttrSpellingListIndex);
2366 else if (const auto *OA = dyn_cast<OptimizeNoneAttr>(Attr))
2367 NewAttr = S.mergeOptimizeNoneAttr(D, OA->getRange(), AttrSpellingListIndex);
2368 else if (const auto *InternalLinkageA = dyn_cast<InternalLinkageAttr>(Attr))
2369 NewAttr = S.mergeInternalLinkageAttr(
2370 D, InternalLinkageA->getRange(),
2371 &S.Context.Idents.get(InternalLinkageA->getSpelling()),
2372 AttrSpellingListIndex);
2373 else if (const auto *CommonA = dyn_cast<CommonAttr>(Attr))
2374 NewAttr = S.mergeCommonAttr(D, CommonA->getRange(),
2375 &S.Context.Idents.get(CommonA->getSpelling()),
2376 AttrSpellingListIndex);
2377 else if (isa<AlignedAttr>(Attr))
2378 // AlignedAttrs are handled separately, because we need to handle all
2379 // such attributes on a declaration at the same time.
2381 else if ((isa<DeprecatedAttr>(Attr) || isa<UnavailableAttr>(Attr)) &&
2382 (AMK == Sema::AMK_Override ||
2383 AMK == Sema::AMK_ProtocolImplementation))
2385 else if (const auto *UA = dyn_cast<UuidAttr>(Attr))
2386 NewAttr = S.mergeUuidAttr(D, UA->getRange(), AttrSpellingListIndex,
2388 else if (Attr->duplicatesAllowed() || !DeclHasAttr(D, Attr))
2389 NewAttr = cast<InheritableAttr>(Attr->clone(S.Context));
2392 NewAttr->setInherited(true);
2393 D->addAttr(NewAttr);
2394 if (isa<MSInheritanceAttr>(NewAttr))
2395 S.Consumer.AssignInheritanceModel(cast<CXXRecordDecl>(D));
2402 static const Decl *getDefinition(const Decl *D) {
2403 if (const TagDecl *TD = dyn_cast<TagDecl>(D))
2404 return TD->getDefinition();
2405 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
2406 const VarDecl *Def = VD->getDefinition();
2409 return VD->getActingDefinition();
2411 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
2412 return FD->getDefinition();
2416 static bool hasAttribute(const Decl *D, attr::Kind Kind) {
2417 for (const auto *Attribute : D->attrs())
2418 if (Attribute->getKind() == Kind)
2423 /// checkNewAttributesAfterDef - If we already have a definition, check that
2424 /// there are no new attributes in this declaration.
2425 static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) {
2426 if (!New->hasAttrs())
2429 const Decl *Def = getDefinition(Old);
2430 if (!Def || Def == New)
2433 AttrVec &NewAttributes = New->getAttrs();
2434 for (unsigned I = 0, E = NewAttributes.size(); I != E;) {
2435 const Attr *NewAttribute = NewAttributes[I];
2437 if (isa<AliasAttr>(NewAttribute) || isa<IFuncAttr>(NewAttribute)) {
2438 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(New)) {
2439 Sema::SkipBodyInfo SkipBody;
2440 S.CheckForFunctionRedefinition(FD, cast<FunctionDecl>(Def), &SkipBody);
2442 // If we're skipping this definition, drop the "alias" attribute.
2443 if (SkipBody.ShouldSkip) {
2444 NewAttributes.erase(NewAttributes.begin() + I);
2449 VarDecl *VD = cast<VarDecl>(New);
2450 unsigned Diag = cast<VarDecl>(Def)->isThisDeclarationADefinition() ==
2451 VarDecl::TentativeDefinition
2452 ? diag::err_alias_after_tentative
2453 : diag::err_redefinition;
2454 S.Diag(VD->getLocation(), Diag) << VD->getDeclName();
2455 S.Diag(Def->getLocation(), diag::note_previous_definition);
2456 VD->setInvalidDecl();
2462 if (const VarDecl *VD = dyn_cast<VarDecl>(Def)) {
2463 // Tentative definitions are only interesting for the alias check above.
2464 if (VD->isThisDeclarationADefinition() != VarDecl::Definition) {
2470 if (hasAttribute(Def, NewAttribute->getKind())) {
2472 continue; // regular attr merging will take care of validating this.
2475 if (isa<C11NoReturnAttr>(NewAttribute)) {
2476 // C's _Noreturn is allowed to be added to a function after it is defined.
2479 } else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) {
2480 if (AA->isAlignas()) {
2481 // C++11 [dcl.align]p6:
2482 // if any declaration of an entity has an alignment-specifier,
2483 // every defining declaration of that entity shall specify an
2484 // equivalent alignment.
2486 // If the definition of an object does not have an alignment
2487 // specifier, any other declaration of that object shall also
2488 // have no alignment specifier.
2489 S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition)
2491 S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration)
2493 NewAttributes.erase(NewAttributes.begin() + I);
2499 S.Diag(NewAttribute->getLocation(),
2500 diag::warn_attribute_precede_definition);
2501 S.Diag(Def->getLocation(), diag::note_previous_definition);
2502 NewAttributes.erase(NewAttributes.begin() + I);
2507 /// mergeDeclAttributes - Copy attributes from the Old decl to the New one.
2508 void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old,
2509 AvailabilityMergeKind AMK) {
2510 if (UsedAttr *OldAttr = Old->getMostRecentDecl()->getAttr<UsedAttr>()) {
2511 UsedAttr *NewAttr = OldAttr->clone(Context);
2512 NewAttr->setInherited(true);
2513 New->addAttr(NewAttr);
2516 if (!Old->hasAttrs() && !New->hasAttrs())
2519 // Attributes declared post-definition are currently ignored.
2520 checkNewAttributesAfterDef(*this, New, Old);
2522 if (AsmLabelAttr *NewA = New->getAttr<AsmLabelAttr>()) {
2523 if (AsmLabelAttr *OldA = Old->getAttr<AsmLabelAttr>()) {
2524 if (OldA->getLabel() != NewA->getLabel()) {
2525 // This redeclaration changes __asm__ label.
2526 Diag(New->getLocation(), diag::err_different_asm_label);
2527 Diag(OldA->getLocation(), diag::note_previous_declaration);
2529 } else if (Old->isUsed()) {
2530 // This redeclaration adds an __asm__ label to a declaration that has
2531 // already been ODR-used.
2532 Diag(New->getLocation(), diag::err_late_asm_label_name)
2533 << isa<FunctionDecl>(Old) << New->getAttr<AsmLabelAttr>()->getRange();
2537 // Re-declaration cannot add abi_tag's.
2538 if (const auto *NewAbiTagAttr = New->getAttr<AbiTagAttr>()) {
2539 if (const auto *OldAbiTagAttr = Old->getAttr<AbiTagAttr>()) {
2540 for (const auto &NewTag : NewAbiTagAttr->tags()) {
2541 if (std::find(OldAbiTagAttr->tags_begin(), OldAbiTagAttr->tags_end(),
2542 NewTag) == OldAbiTagAttr->tags_end()) {
2543 Diag(NewAbiTagAttr->getLocation(),
2544 diag::err_new_abi_tag_on_redeclaration)
2546 Diag(OldAbiTagAttr->getLocation(), diag::note_previous_declaration);
2550 Diag(NewAbiTagAttr->getLocation(), diag::err_abi_tag_on_redeclaration);
2551 Diag(Old->getLocation(), diag::note_previous_declaration);
2555 if (!Old->hasAttrs())
2558 bool foundAny = New->hasAttrs();
2560 // Ensure that any moving of objects within the allocated map is done before
2562 if (!foundAny) New->setAttrs(AttrVec());
2564 for (auto *I : Old->specific_attrs<InheritableAttr>()) {
2565 // Ignore deprecated/unavailable/availability attributes if requested.
2566 AvailabilityMergeKind LocalAMK = AMK_None;
2567 if (isa<DeprecatedAttr>(I) ||
2568 isa<UnavailableAttr>(I) ||
2569 isa<AvailabilityAttr>(I)) {
2574 case AMK_Redeclaration:
2576 case AMK_ProtocolImplementation:
2583 if (isa<UsedAttr>(I))
2586 if (mergeDeclAttribute(*this, New, I, LocalAMK))
2590 if (mergeAlignedAttrs(*this, New, Old))
2593 if (!foundAny) New->dropAttrs();
2596 /// mergeParamDeclAttributes - Copy attributes from the old parameter
2598 static void mergeParamDeclAttributes(ParmVarDecl *newDecl,
2599 const ParmVarDecl *oldDecl,
2601 // C++11 [dcl.attr.depend]p2:
2602 // The first declaration of a function shall specify the
2603 // carries_dependency attribute for its declarator-id if any declaration
2604 // of the function specifies the carries_dependency attribute.
2605 const CarriesDependencyAttr *CDA = newDecl->getAttr<CarriesDependencyAttr>();
2606 if (CDA && !oldDecl->hasAttr<CarriesDependencyAttr>()) {
2607 S.Diag(CDA->getLocation(),
2608 diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/;
2609 // Find the first declaration of the parameter.
2610 // FIXME: Should we build redeclaration chains for function parameters?
2611 const FunctionDecl *FirstFD =
2612 cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDecl();
2613 const ParmVarDecl *FirstVD =
2614 FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex());
2615 S.Diag(FirstVD->getLocation(),
2616 diag::note_carries_dependency_missing_first_decl) << 1/*Param*/;
2619 if (!oldDecl->hasAttrs())
2622 bool foundAny = newDecl->hasAttrs();
2624 // Ensure that any moving of objects within the allocated map is
2625 // done before we process them.
2626 if (!foundAny) newDecl->setAttrs(AttrVec());
2628 for (const auto *I : oldDecl->specific_attrs<InheritableParamAttr>()) {
2629 if (!DeclHasAttr(newDecl, I)) {
2630 InheritableAttr *newAttr =
2631 cast<InheritableParamAttr>(I->clone(S.Context));
2632 newAttr->setInherited(true);
2633 newDecl->addAttr(newAttr);
2638 if (!foundAny) newDecl->dropAttrs();
2641 static void mergeParamDeclTypes(ParmVarDecl *NewParam,
2642 const ParmVarDecl *OldParam,
2644 if (auto Oldnullability = OldParam->getType()->getNullability(S.Context)) {
2645 if (auto Newnullability = NewParam->getType()->getNullability(S.Context)) {
2646 if (*Oldnullability != *Newnullability) {
2647 S.Diag(NewParam->getLocation(), diag::warn_mismatched_nullability_attr)
2648 << DiagNullabilityKind(
2650 ((NewParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2652 << DiagNullabilityKind(
2654 ((OldParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2656 S.Diag(OldParam->getLocation(), diag::note_previous_declaration);
2659 QualType NewT = NewParam->getType();
2660 NewT = S.Context.getAttributedType(
2661 AttributedType::getNullabilityAttrKind(*Oldnullability),
2663 NewParam->setType(NewT);
2670 /// Used in MergeFunctionDecl to keep track of function parameters in
2672 struct GNUCompatibleParamWarning {
2673 ParmVarDecl *OldParm;
2674 ParmVarDecl *NewParm;
2675 QualType PromotedType;
2678 } // end anonymous namespace
2680 /// getSpecialMember - get the special member enum for a method.
2681 Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) {
2682 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
2683 if (Ctor->isDefaultConstructor())
2684 return Sema::CXXDefaultConstructor;
2686 if (Ctor->isCopyConstructor())
2687 return Sema::CXXCopyConstructor;
2689 if (Ctor->isMoveConstructor())
2690 return Sema::CXXMoveConstructor;
2691 } else if (isa<CXXDestructorDecl>(MD)) {
2692 return Sema::CXXDestructor;
2693 } else if (MD->isCopyAssignmentOperator()) {
2694 return Sema::CXXCopyAssignment;
2695 } else if (MD->isMoveAssignmentOperator()) {
2696 return Sema::CXXMoveAssignment;
2699 return Sema::CXXInvalid;
2702 // Determine whether the previous declaration was a definition, implicit
2703 // declaration, or a declaration.
2704 template <typename T>
2705 static std::pair<diag::kind, SourceLocation>
2706 getNoteDiagForInvalidRedeclaration(const T *Old, const T *New) {
2707 diag::kind PrevDiag;
2708 SourceLocation OldLocation = Old->getLocation();
2709 if (Old->isThisDeclarationADefinition())
2710 PrevDiag = diag::note_previous_definition;
2711 else if (Old->isImplicit()) {
2712 PrevDiag = diag::note_previous_implicit_declaration;
2713 if (OldLocation.isInvalid())
2714 OldLocation = New->getLocation();
2716 PrevDiag = diag::note_previous_declaration;
2717 return std::make_pair(PrevDiag, OldLocation);
2720 /// canRedefineFunction - checks if a function can be redefined. Currently,
2721 /// only extern inline functions can be redefined, and even then only in
2723 static bool canRedefineFunction(const FunctionDecl *FD,
2724 const LangOptions& LangOpts) {
2725 return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) &&
2726 !LangOpts.CPlusPlus &&
2727 FD->isInlineSpecified() &&
2728 FD->getStorageClass() == SC_Extern);
2731 const AttributedType *Sema::getCallingConvAttributedType(QualType T) const {
2732 const AttributedType *AT = T->getAs<AttributedType>();
2733 while (AT && !AT->isCallingConv())
2734 AT = AT->getModifiedType()->getAs<AttributedType>();
2738 template <typename T>
2739 static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) {
2740 const DeclContext *DC = Old->getDeclContext();
2744 LanguageLinkage OldLinkage = Old->getLanguageLinkage();
2745 if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext())
2747 if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext())
2752 template<typename T> static bool isExternC(T *D) { return D->isExternC(); }
2753 static bool isExternC(VarTemplateDecl *) { return false; }
2755 /// \brief Check whether a redeclaration of an entity introduced by a
2756 /// using-declaration is valid, given that we know it's not an overload
2757 /// (nor a hidden tag declaration).
2758 template<typename ExpectedDecl>
2759 static bool checkUsingShadowRedecl(Sema &S, UsingShadowDecl *OldS,
2760 ExpectedDecl *New) {
2761 // C++11 [basic.scope.declarative]p4:
2762 // Given a set of declarations in a single declarative region, each of
2763 // which specifies the same unqualified name,
2764 // -- they shall all refer to the same entity, or all refer to functions
2765 // and function templates; or
2766 // -- exactly one declaration shall declare a class name or enumeration
2767 // name that is not a typedef name and the other declarations shall all
2768 // refer to the same variable or enumerator, or all refer to functions
2769 // and function templates; in this case the class name or enumeration
2770 // name is hidden (3.3.10).
2772 // C++11 [namespace.udecl]p14:
2773 // If a function declaration in namespace scope or block scope has the
2774 // same name and the same parameter-type-list as a function introduced
2775 // by a using-declaration, and the declarations do not declare the same
2776 // function, the program is ill-formed.
2778 auto *Old = dyn_cast<ExpectedDecl>(OldS->getTargetDecl());
2780 !Old->getDeclContext()->getRedeclContext()->Equals(
2781 New->getDeclContext()->getRedeclContext()) &&
2782 !(isExternC(Old) && isExternC(New)))
2786 S.Diag(New->getLocation(), diag::err_using_decl_conflict_reverse);
2787 S.Diag(OldS->getTargetDecl()->getLocation(), diag::note_using_decl_target);
2788 S.Diag(OldS->getUsingDecl()->getLocation(), diag::note_using_decl) << 0;
2794 static bool hasIdenticalPassObjectSizeAttrs(const FunctionDecl *A,
2795 const FunctionDecl *B) {
2796 assert(A->getNumParams() == B->getNumParams());
2798 auto AttrEq = [](const ParmVarDecl *A, const ParmVarDecl *B) {
2799 const auto *AttrA = A->getAttr<PassObjectSizeAttr>();
2800 const auto *AttrB = B->getAttr<PassObjectSizeAttr>();
2803 return AttrA && AttrB && AttrA->getType() == AttrB->getType();
2806 return std::equal(A->param_begin(), A->param_end(), B->param_begin(), AttrEq);
2809 /// MergeFunctionDecl - We just parsed a function 'New' from
2810 /// declarator D which has the same name and scope as a previous
2811 /// declaration 'Old'. Figure out how to resolve this situation,
2812 /// merging decls or emitting diagnostics as appropriate.
2814 /// In C++, New and Old must be declarations that are not
2815 /// overloaded. Use IsOverload to determine whether New and Old are
2816 /// overloaded, and to select the Old declaration that New should be
2819 /// Returns true if there was an error, false otherwise.
2820 bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
2821 Scope *S, bool MergeTypeWithOld) {
2822 // Verify the old decl was also a function.
2823 FunctionDecl *Old = OldD->getAsFunction();
2825 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) {
2826 if (New->getFriendObjectKind()) {
2827 Diag(New->getLocation(), diag::err_using_decl_friend);
2828 Diag(Shadow->getTargetDecl()->getLocation(),
2829 diag::note_using_decl_target);
2830 Diag(Shadow->getUsingDecl()->getLocation(),
2831 diag::note_using_decl) << 0;
2835 // Check whether the two declarations might declare the same function.
2836 if (checkUsingShadowRedecl<FunctionDecl>(*this, Shadow, New))
2838 OldD = Old = cast<FunctionDecl>(Shadow->getTargetDecl());
2840 Diag(New->getLocation(), diag::err_redefinition_different_kind)
2841 << New->getDeclName();
2842 Diag(OldD->getLocation(), diag::note_previous_definition);
2847 // If the old declaration is invalid, just give up here.
2848 if (Old->isInvalidDecl())
2851 diag::kind PrevDiag;
2852 SourceLocation OldLocation;
2853 std::tie(PrevDiag, OldLocation) =
2854 getNoteDiagForInvalidRedeclaration(Old, New);
2856 // Don't complain about this if we're in GNU89 mode and the old function
2857 // is an extern inline function.
2858 // Don't complain about specializations. They are not supposed to have
2860 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) &&
2861 New->getStorageClass() == SC_Static &&
2862 Old->hasExternalFormalLinkage() &&
2863 !New->getTemplateSpecializationInfo() &&
2864 !canRedefineFunction(Old, getLangOpts())) {
2865 if (getLangOpts().MicrosoftExt) {
2866 Diag(New->getLocation(), diag::ext_static_non_static) << New;
2867 Diag(OldLocation, PrevDiag);
2869 Diag(New->getLocation(), diag::err_static_non_static) << New;
2870 Diag(OldLocation, PrevDiag);
2875 if (New->hasAttr<InternalLinkageAttr>() &&
2876 !Old->hasAttr<InternalLinkageAttr>()) {
2877 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
2878 << New->getDeclName();
2879 Diag(Old->getLocation(), diag::note_previous_definition);
2880 New->dropAttr<InternalLinkageAttr>();
2883 // If a function is first declared with a calling convention, but is later
2884 // declared or defined without one, all following decls assume the calling
2885 // convention of the first.
2887 // It's OK if a function is first declared without a calling convention,
2888 // but is later declared or defined with the default calling convention.
2890 // To test if either decl has an explicit calling convention, we look for
2891 // AttributedType sugar nodes on the type as written. If they are missing or
2892 // were canonicalized away, we assume the calling convention was implicit.
2894 // Note also that we DO NOT return at this point, because we still have
2895 // other tests to run.
2896 QualType OldQType = Context.getCanonicalType(Old->getType());
2897 QualType NewQType = Context.getCanonicalType(New->getType());
2898 const FunctionType *OldType = cast<FunctionType>(OldQType);
2899 const FunctionType *NewType = cast<FunctionType>(NewQType);
2900 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo();
2901 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo();
2902 bool RequiresAdjustment = false;
2904 if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) {
2905 FunctionDecl *First = Old->getFirstDecl();
2906 const FunctionType *FT =
2907 First->getType().getCanonicalType()->castAs<FunctionType>();
2908 FunctionType::ExtInfo FI = FT->getExtInfo();
2909 bool NewCCExplicit = getCallingConvAttributedType(New->getType());
2910 if (!NewCCExplicit) {
2911 // Inherit the CC from the previous declaration if it was specified
2912 // there but not here.
2913 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
2914 RequiresAdjustment = true;
2916 // Calling conventions aren't compatible, so complain.
2917 bool FirstCCExplicit = getCallingConvAttributedType(First->getType());
2918 Diag(New->getLocation(), diag::err_cconv_change)
2919 << FunctionType::getNameForCallConv(NewTypeInfo.getCC())
2921 << (!FirstCCExplicit ? "" :
2922 FunctionType::getNameForCallConv(FI.getCC()));
2924 // Put the note on the first decl, since it is the one that matters.
2925 Diag(First->getLocation(), diag::note_previous_declaration);
2930 // FIXME: diagnose the other way around?
2931 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) {
2932 NewTypeInfo = NewTypeInfo.withNoReturn(true);
2933 RequiresAdjustment = true;
2936 // Merge regparm attribute.
2937 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() ||
2938 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) {
2939 if (NewTypeInfo.getHasRegParm()) {
2940 Diag(New->getLocation(), diag::err_regparm_mismatch)
2941 << NewType->getRegParmType()
2942 << OldType->getRegParmType();
2943 Diag(OldLocation, diag::note_previous_declaration);
2947 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm());
2948 RequiresAdjustment = true;
2951 // Merge ns_returns_retained attribute.
2952 if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) {
2953 if (NewTypeInfo.getProducesResult()) {
2954 Diag(New->getLocation(), diag::err_function_attribute_mismatch)
2955 << "'ns_returns_retained'";
2956 Diag(OldLocation, diag::note_previous_declaration);
2960 NewTypeInfo = NewTypeInfo.withProducesResult(true);
2961 RequiresAdjustment = true;
2964 if (OldTypeInfo.getNoCallerSavedRegs() !=
2965 NewTypeInfo.getNoCallerSavedRegs()) {
2966 if (NewTypeInfo.getNoCallerSavedRegs()) {
2967 AnyX86NoCallerSavedRegistersAttr *Attr =
2968 New->getAttr<AnyX86NoCallerSavedRegistersAttr>();
2969 Diag(New->getLocation(), diag::err_function_attribute_mismatch) << Attr;
2970 Diag(OldLocation, diag::note_previous_declaration);
2974 NewTypeInfo = NewTypeInfo.withNoCallerSavedRegs(true);
2975 RequiresAdjustment = true;
2978 if (RequiresAdjustment) {
2979 const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>();
2980 AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo);
2981 New->setType(QualType(AdjustedType, 0));
2982 NewQType = Context.getCanonicalType(New->getType());
2983 NewType = cast<FunctionType>(NewQType);
2986 // If this redeclaration makes the function inline, we may need to add it to
2987 // UndefinedButUsed.
2988 if (!Old->isInlined() && New->isInlined() &&
2989 !New->hasAttr<GNUInlineAttr>() &&
2990 !getLangOpts().GNUInline &&
2991 Old->isUsed(false) &&
2992 !Old->isDefined() && !New->isThisDeclarationADefinition())
2993 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
2996 // If this redeclaration makes it newly gnu_inline, we don't want to warn
2998 if (New->hasAttr<GNUInlineAttr>() &&
2999 Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) {
3000 UndefinedButUsed.erase(Old->getCanonicalDecl());
3003 // If pass_object_size params don't match up perfectly, this isn't a valid
3005 if (Old->getNumParams() > 0 && Old->getNumParams() == New->getNumParams() &&
3006 !hasIdenticalPassObjectSizeAttrs(Old, New)) {
3007 Diag(New->getLocation(), diag::err_different_pass_object_size_params)
3008 << New->getDeclName();
3009 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3013 if (getLangOpts().CPlusPlus) {
3014 // C++1z [over.load]p2
3015 // Certain function declarations cannot be overloaded:
3016 // -- Function declarations that differ only in the return type,
3017 // the exception specification, or both cannot be overloaded.
3019 // Check the exception specifications match. This may recompute the type of
3020 // both Old and New if it resolved exception specifications, so grab the
3021 // types again after this. Because this updates the type, we do this before
3022 // any of the other checks below, which may update the "de facto" NewQType
3023 // but do not necessarily update the type of New.
3024 if (CheckEquivalentExceptionSpec(Old, New))
3026 OldQType = Context.getCanonicalType(Old->getType());
3027 NewQType = Context.getCanonicalType(New->getType());
3029 // Go back to the type source info to compare the declared return types,
3030 // per C++1y [dcl.type.auto]p13:
3031 // Redeclarations or specializations of a function or function template
3032 // with a declared return type that uses a placeholder type shall also
3033 // use that placeholder, not a deduced type.
3034 QualType OldDeclaredReturnType =
3035 (Old->getTypeSourceInfo()
3036 ? Old->getTypeSourceInfo()->getType()->castAs<FunctionType>()
3037 : OldType)->getReturnType();
3038 QualType NewDeclaredReturnType =
3039 (New->getTypeSourceInfo()
3040 ? New->getTypeSourceInfo()->getType()->castAs<FunctionType>()
3041 : NewType)->getReturnType();
3042 if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType) &&
3043 !((NewQType->isDependentType() || OldQType->isDependentType()) &&
3044 New->isLocalExternDecl())) {
3046 if (NewDeclaredReturnType->isObjCObjectPointerType() &&
3047 OldDeclaredReturnType->isObjCObjectPointerType())
3048 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType);
3049 if (ResQT.isNull()) {
3050 if (New->isCXXClassMember() && New->isOutOfLine())
3051 Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type)
3052 << New << New->getReturnTypeSourceRange();
3054 Diag(New->getLocation(), diag::err_ovl_diff_return_type)
3055 << New->getReturnTypeSourceRange();
3056 Diag(OldLocation, PrevDiag) << Old << Old->getType()
3057 << Old->getReturnTypeSourceRange();
3064 QualType OldReturnType = OldType->getReturnType();
3065 QualType NewReturnType = cast<FunctionType>(NewQType)->getReturnType();
3066 if (OldReturnType != NewReturnType) {
3067 // If this function has a deduced return type and has already been
3068 // defined, copy the deduced value from the old declaration.
3069 AutoType *OldAT = Old->getReturnType()->getContainedAutoType();
3070 if (OldAT && OldAT->isDeduced()) {
3072 SubstAutoType(New->getType(),
3073 OldAT->isDependentType() ? Context.DependentTy
3074 : OldAT->getDeducedType()));
3075 NewQType = Context.getCanonicalType(
3076 SubstAutoType(NewQType,
3077 OldAT->isDependentType() ? Context.DependentTy
3078 : OldAT->getDeducedType()));
3082 const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
3083 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
3084 if (OldMethod && NewMethod) {
3085 // Preserve triviality.
3086 NewMethod->setTrivial(OldMethod->isTrivial());
3088 // MSVC allows explicit template specialization at class scope:
3089 // 2 CXXMethodDecls referring to the same function will be injected.
3090 // We don't want a redeclaration error.
3091 bool IsClassScopeExplicitSpecialization =
3092 OldMethod->isFunctionTemplateSpecialization() &&
3093 NewMethod->isFunctionTemplateSpecialization();
3094 bool isFriend = NewMethod->getFriendObjectKind();
3096 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() &&
3097 !IsClassScopeExplicitSpecialization) {
3098 // -- Member function declarations with the same name and the
3099 // same parameter types cannot be overloaded if any of them
3100 // is a static member function declaration.
3101 if (OldMethod->isStatic() != NewMethod->isStatic()) {
3102 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
3103 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3107 // C++ [class.mem]p1:
3108 // [...] A member shall not be declared twice in the
3109 // member-specification, except that a nested class or member
3110 // class template can be declared and then later defined.
3111 if (!inTemplateInstantiation()) {
3113 if (isa<CXXConstructorDecl>(OldMethod))
3114 NewDiag = diag::err_constructor_redeclared;
3115 else if (isa<CXXDestructorDecl>(NewMethod))
3116 NewDiag = diag::err_destructor_redeclared;
3117 else if (isa<CXXConversionDecl>(NewMethod))
3118 NewDiag = diag::err_conv_function_redeclared;
3120 NewDiag = diag::err_member_redeclared;
3122 Diag(New->getLocation(), NewDiag);
3124 Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation)
3125 << New << New->getType();
3127 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3130 // Complain if this is an explicit declaration of a special
3131 // member that was initially declared implicitly.
3133 // As an exception, it's okay to befriend such methods in order
3134 // to permit the implicit constructor/destructor/operator calls.
3135 } else if (OldMethod->isImplicit()) {
3137 NewMethod->setImplicit();
3139 Diag(NewMethod->getLocation(),
3140 diag::err_definition_of_implicitly_declared_member)
3141 << New << getSpecialMember(OldMethod);
3144 } else if (OldMethod->getFirstDecl()->isExplicitlyDefaulted() && !isFriend) {
3145 Diag(NewMethod->getLocation(),
3146 diag::err_definition_of_explicitly_defaulted_member)
3147 << getSpecialMember(OldMethod);
3152 // C++11 [dcl.attr.noreturn]p1:
3153 // The first declaration of a function shall specify the noreturn
3154 // attribute if any declaration of that function specifies the noreturn
3156 const CXX11NoReturnAttr *NRA = New->getAttr<CXX11NoReturnAttr>();
3157 if (NRA && !Old->hasAttr<CXX11NoReturnAttr>()) {
3158 Diag(NRA->getLocation(), diag::err_noreturn_missing_on_first_decl);
3159 Diag(Old->getFirstDecl()->getLocation(),
3160 diag::note_noreturn_missing_first_decl);
3163 // C++11 [dcl.attr.depend]p2:
3164 // The first declaration of a function shall specify the
3165 // carries_dependency attribute for its declarator-id if any declaration
3166 // of the function specifies the carries_dependency attribute.
3167 const CarriesDependencyAttr *CDA = New->getAttr<CarriesDependencyAttr>();
3168 if (CDA && !Old->hasAttr<CarriesDependencyAttr>()) {
3169 Diag(CDA->getLocation(),
3170 diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/;
3171 Diag(Old->getFirstDecl()->getLocation(),
3172 diag::note_carries_dependency_missing_first_decl) << 0/*Function*/;
3176 // All declarations for a function shall agree exactly in both the
3177 // return type and the parameter-type-list.
3178 // We also want to respect all the extended bits except noreturn.
3180 // noreturn should now match unless the old type info didn't have it.
3181 QualType OldQTypeForComparison = OldQType;
3182 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) {
3183 auto *OldType = OldQType->castAs<FunctionProtoType>();
3184 const FunctionType *OldTypeForComparison
3185 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true));
3186 OldQTypeForComparison = QualType(OldTypeForComparison, 0);
3187 assert(OldQTypeForComparison.isCanonical());
3190 if (haveIncompatibleLanguageLinkages(Old, New)) {
3191 // As a special case, retain the language linkage from previous
3192 // declarations of a friend function as an extension.
3194 // This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC
3195 // and is useful because there's otherwise no way to specify language
3196 // linkage within class scope.
3198 // Check cautiously as the friend object kind isn't yet complete.
3199 if (New->getFriendObjectKind() != Decl::FOK_None) {
3200 Diag(New->getLocation(), diag::ext_retained_language_linkage) << New;
3201 Diag(OldLocation, PrevDiag);
3203 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3204 Diag(OldLocation, PrevDiag);
3209 if (OldQTypeForComparison == NewQType)
3210 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3212 if ((NewQType->isDependentType() || OldQType->isDependentType()) &&
3213 New->isLocalExternDecl()) {
3214 // It's OK if we couldn't merge types for a local function declaraton
3215 // if either the old or new type is dependent. We'll merge the types
3216 // when we instantiate the function.
3220 // Fall through for conflicting redeclarations and redefinitions.
3223 // C: Function types need to be compatible, not identical. This handles
3224 // duplicate function decls like "void f(int); void f(enum X);" properly.
3225 if (!getLangOpts().CPlusPlus &&
3226 Context.typesAreCompatible(OldQType, NewQType)) {
3227 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>();
3228 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>();
3229 const FunctionProtoType *OldProto = nullptr;
3230 if (MergeTypeWithOld && isa<FunctionNoProtoType>(NewFuncType) &&
3231 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) {
3232 // The old declaration provided a function prototype, but the
3233 // new declaration does not. Merge in the prototype.
3234 assert(!OldProto->hasExceptionSpec() && "Exception spec in C");
3235 SmallVector<QualType, 16> ParamTypes(OldProto->param_types());
3237 Context.getFunctionType(NewFuncType->getReturnType(), ParamTypes,
3238 OldProto->getExtProtoInfo());
3239 New->setType(NewQType);
3240 New->setHasInheritedPrototype();
3242 // Synthesize parameters with the same types.
3243 SmallVector<ParmVarDecl*, 16> Params;
3244 for (const auto &ParamType : OldProto->param_types()) {
3245 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(),
3246 SourceLocation(), nullptr,
3247 ParamType, /*TInfo=*/nullptr,
3249 Param->setScopeInfo(0, Params.size());
3250 Param->setImplicit();
3251 Params.push_back(Param);
3254 New->setParams(Params);
3257 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3260 // GNU C permits a K&R definition to follow a prototype declaration
3261 // if the declared types of the parameters in the K&R definition
3262 // match the types in the prototype declaration, even when the
3263 // promoted types of the parameters from the K&R definition differ
3264 // from the types in the prototype. GCC then keeps the types from
3267 // If a variadic prototype is followed by a non-variadic K&R definition,
3268 // the K&R definition becomes variadic. This is sort of an edge case, but
3269 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and
3271 if (!getLangOpts().CPlusPlus &&
3272 Old->hasPrototype() && !New->hasPrototype() &&
3273 New->getType()->getAs<FunctionProtoType>() &&
3274 Old->getNumParams() == New->getNumParams()) {
3275 SmallVector<QualType, 16> ArgTypes;
3276 SmallVector<GNUCompatibleParamWarning, 16> Warnings;
3277 const FunctionProtoType *OldProto
3278 = Old->getType()->getAs<FunctionProtoType>();
3279 const FunctionProtoType *NewProto
3280 = New->getType()->getAs<FunctionProtoType>();
3282 // Determine whether this is the GNU C extension.
3283 QualType MergedReturn = Context.mergeTypes(OldProto->getReturnType(),
3284 NewProto->getReturnType());
3285 bool LooseCompatible = !MergedReturn.isNull();
3286 for (unsigned Idx = 0, End = Old->getNumParams();
3287 LooseCompatible && Idx != End; ++Idx) {
3288 ParmVarDecl *OldParm = Old->getParamDecl(Idx);
3289 ParmVarDecl *NewParm = New->getParamDecl(Idx);
3290 if (Context.typesAreCompatible(OldParm->getType(),
3291 NewProto->getParamType(Idx))) {
3292 ArgTypes.push_back(NewParm->getType());
3293 } else if (Context.typesAreCompatible(OldParm->getType(),
3295 /*CompareUnqualified=*/true)) {
3296 GNUCompatibleParamWarning Warn = { OldParm, NewParm,
3297 NewProto->getParamType(Idx) };
3298 Warnings.push_back(Warn);
3299 ArgTypes.push_back(NewParm->getType());
3301 LooseCompatible = false;
3304 if (LooseCompatible) {
3305 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) {
3306 Diag(Warnings[Warn].NewParm->getLocation(),
3307 diag::ext_param_promoted_not_compatible_with_prototype)
3308 << Warnings[Warn].PromotedType
3309 << Warnings[Warn].OldParm->getType();
3310 if (Warnings[Warn].OldParm->getLocation().isValid())
3311 Diag(Warnings[Warn].OldParm->getLocation(),
3312 diag::note_previous_declaration);
3315 if (MergeTypeWithOld)
3316 New->setType(Context.getFunctionType(MergedReturn, ArgTypes,
3317 OldProto->getExtProtoInfo()));
3318 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3321 // Fall through to diagnose conflicting types.
3324 // A function that has already been declared has been redeclared or
3325 // defined with a different type; show an appropriate diagnostic.
3327 // If the previous declaration was an implicitly-generated builtin
3328 // declaration, then at the very least we should use a specialized note.
3330 if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) {
3331 // If it's actually a library-defined builtin function like 'malloc'
3332 // or 'printf', just warn about the incompatible redeclaration.
3333 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) {
3334 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New;
3335 Diag(OldLocation, diag::note_previous_builtin_declaration)
3336 << Old << Old->getType();
3338 // If this is a global redeclaration, just forget hereafter
3339 // about the "builtin-ness" of the function.
3341 // Doing this for local extern declarations is problematic. If
3342 // the builtin declaration remains visible, a second invalid
3343 // local declaration will produce a hard error; if it doesn't
3344 // remain visible, a single bogus local redeclaration (which is
3345 // actually only a warning) could break all the downstream code.
3346 if (!New->getLexicalDeclContext()->isFunctionOrMethod())
3347 New->getIdentifier()->revertBuiltin();
3352 PrevDiag = diag::note_previous_builtin_declaration;
3355 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName();
3356 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3360 /// \brief Completes the merge of two function declarations that are
3361 /// known to be compatible.
3363 /// This routine handles the merging of attributes and other
3364 /// properties of function declarations from the old declaration to
3365 /// the new declaration, once we know that New is in fact a
3366 /// redeclaration of Old.
3369 bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
3370 Scope *S, bool MergeTypeWithOld) {
3371 // Merge the attributes
3372 mergeDeclAttributes(New, Old);
3374 // Merge "pure" flag.
3378 // Merge "used" flag.
3379 if (Old->getMostRecentDecl()->isUsed(false))
3382 // Merge attributes from the parameters. These can mismatch with K&R
3384 if (New->getNumParams() == Old->getNumParams())
3385 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) {
3386 ParmVarDecl *NewParam = New->getParamDecl(i);
3387 ParmVarDecl *OldParam = Old->getParamDecl(i);
3388 mergeParamDeclAttributes(NewParam, OldParam, *this);
3389 mergeParamDeclTypes(NewParam, OldParam, *this);
3392 if (getLangOpts().CPlusPlus)
3393 return MergeCXXFunctionDecl(New, Old, S);
3395 // Merge the function types so the we get the composite types for the return
3396 // and argument types. Per C11 6.2.7/4, only update the type if the old decl
3398 QualType Merged = Context.mergeTypes(Old->getType(), New->getType());
3399 if (!Merged.isNull() && MergeTypeWithOld)
3400 New->setType(Merged);
3405 void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod,
3406 ObjCMethodDecl *oldMethod) {
3407 // Merge the attributes, including deprecated/unavailable
3408 AvailabilityMergeKind MergeKind =
3409 isa<ObjCProtocolDecl>(oldMethod->getDeclContext())
3410 ? AMK_ProtocolImplementation
3411 : isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration
3414 mergeDeclAttributes(newMethod, oldMethod, MergeKind);
3416 // Merge attributes from the parameters.
3417 ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(),
3418 oe = oldMethod->param_end();
3419 for (ObjCMethodDecl::param_iterator
3420 ni = newMethod->param_begin(), ne = newMethod->param_end();
3421 ni != ne && oi != oe; ++ni, ++oi)
3422 mergeParamDeclAttributes(*ni, *oi, *this);
3424 CheckObjCMethodOverride(newMethod, oldMethod);
3427 static void diagnoseVarDeclTypeMismatch(Sema &S, VarDecl *New, VarDecl* Old) {
3428 assert(!S.Context.hasSameType(New->getType(), Old->getType()));
3430 S.Diag(New->getLocation(), New->isThisDeclarationADefinition()
3431 ? diag::err_redefinition_different_type
3432 : diag::err_redeclaration_different_type)
3433 << New->getDeclName() << New->getType() << Old->getType();
3435 diag::kind PrevDiag;
3436 SourceLocation OldLocation;
3437 std::tie(PrevDiag, OldLocation)
3438 = getNoteDiagForInvalidRedeclaration(Old, New);
3439 S.Diag(OldLocation, PrevDiag);
3440 New->setInvalidDecl();
3443 /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and
3444 /// scope as a previous declaration 'Old'. Figure out how to merge their types,
3445 /// emitting diagnostics as appropriate.
3447 /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back
3448 /// to here in AddInitializerToDecl. We can't check them before the initializer
3450 void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old,
3451 bool MergeTypeWithOld) {
3452 if (New->isInvalidDecl() || Old->isInvalidDecl())
3456 if (getLangOpts().CPlusPlus) {
3457 if (New->getType()->isUndeducedType()) {
3458 // We don't know what the new type is until the initializer is attached.
3460 } else if (Context.hasSameType(New->getType(), Old->getType())) {
3461 // These could still be something that needs exception specs checked.
3462 return MergeVarDeclExceptionSpecs(New, Old);
3464 // C++ [basic.link]p10:
3465 // [...] the types specified by all declarations referring to a given
3466 // object or function shall be identical, except that declarations for an
3467 // array object can specify array types that differ by the presence or
3468 // absence of a major array bound (8.3.4).
3469 else if (Old->getType()->isArrayType() && New->getType()->isArrayType()) {
3470 const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
3471 const ArrayType *NewArray = Context.getAsArrayType(New->getType());
3473 // We are merging a variable declaration New into Old. If it has an array
3474 // bound, and that bound differs from Old's bound, we should diagnose the
3476 if (!NewArray->isIncompleteArrayType() && !NewArray->isDependentType()) {
3477 for (VarDecl *PrevVD = Old->getMostRecentDecl(); PrevVD;
3478 PrevVD = PrevVD->getPreviousDecl()) {
3479 const ArrayType *PrevVDTy = Context.getAsArrayType(PrevVD->getType());
3480 if (PrevVDTy->isIncompleteArrayType() || PrevVDTy->isDependentType())
3483 if (!Context.hasSameType(NewArray, PrevVDTy))
3484 return diagnoseVarDeclTypeMismatch(*this, New, PrevVD);
3488 if (OldArray->isIncompleteArrayType() && NewArray->isArrayType()) {
3489 if (Context.hasSameType(OldArray->getElementType(),
3490 NewArray->getElementType()))
3491 MergedT = New->getType();
3493 // FIXME: Check visibility. New is hidden but has a complete type. If New
3494 // has no array bound, it should not inherit one from Old, if Old is not
3496 else if (OldArray->isArrayType() && NewArray->isIncompleteArrayType()) {
3497 if (Context.hasSameType(OldArray->getElementType(),
3498 NewArray->getElementType()))
3499 MergedT = Old->getType();
3502 else if (New->getType()->isObjCObjectPointerType() &&
3503 Old->getType()->isObjCObjectPointerType()) {
3504 MergedT = Context.mergeObjCGCQualifiers(New->getType(),
3509 // All declarations that refer to the same object or function shall have
3511 MergedT = Context.mergeTypes(New->getType(), Old->getType());
3513 if (MergedT.isNull()) {
3514 // It's OK if we couldn't merge types if either type is dependent, for a
3515 // block-scope variable. In other cases (static data members of class
3516 // templates, variable templates, ...), we require the types to be
3518 // FIXME: The C++ standard doesn't say anything about this.
3519 if ((New->getType()->isDependentType() ||
3520 Old->getType()->isDependentType()) && New->isLocalVarDecl()) {
3521 // If the old type was dependent, we can't merge with it, so the new type
3522 // becomes dependent for now. We'll reproduce the original type when we
3523 // instantiate the TypeSourceInfo for the variable.
3524 if (!New->getType()->isDependentType() && MergeTypeWithOld)
3525 New->setType(Context.DependentTy);
3528 return diagnoseVarDeclTypeMismatch(*this, New, Old);
3531 // Don't actually update the type on the new declaration if the old
3532 // declaration was an extern declaration in a different scope.
3533 if (MergeTypeWithOld)
3534 New->setType(MergedT);
3537 static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD,
3538 LookupResult &Previous) {
3540 // For an identifier with internal or external linkage declared
3541 // in a scope in which a prior declaration of that identifier is
3542 // visible, if the prior declaration specifies internal or
3543 // external linkage, the type of the identifier at the later
3544 // declaration becomes the composite type.
3546 // If the variable isn't visible, we do not merge with its type.
3547 if (Previous.isShadowed())
3550 if (S.getLangOpts().CPlusPlus) {
3551 // C++11 [dcl.array]p3:
3552 // If there is a preceding declaration of the entity in the same
3553 // scope in which the bound was specified, an omitted array bound
3554 // is taken to be the same as in that earlier declaration.
3555 return NewVD->isPreviousDeclInSameBlockScope() ||
3556 (!OldVD->getLexicalDeclContext()->isFunctionOrMethod() &&
3557 !NewVD->getLexicalDeclContext()->isFunctionOrMethod());
3559 // If the old declaration was function-local, don't merge with its
3560 // type unless we're in the same function.
3561 return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() ||
3562 OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext();
3566 /// MergeVarDecl - We just parsed a variable 'New' which has the same name
3567 /// and scope as a previous declaration 'Old'. Figure out how to resolve this
3568 /// situation, merging decls or emitting diagnostics as appropriate.
3570 /// Tentative definition rules (C99 6.9.2p2) are checked by
3571 /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative
3572 /// definitions here, since the initializer hasn't been attached.
3574 void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
3575 // If the new decl is already invalid, don't do any other checking.
3576 if (New->isInvalidDecl())
3579 if (!shouldLinkPossiblyHiddenDecl(Previous, New))
3582 VarTemplateDecl *NewTemplate = New->getDescribedVarTemplate();
3584 // Verify the old decl was also a variable or variable template.
3585 VarDecl *Old = nullptr;
3586 VarTemplateDecl *OldTemplate = nullptr;
3587 if (Previous.isSingleResult()) {
3589 OldTemplate = dyn_cast<VarTemplateDecl>(Previous.getFoundDecl());
3590 Old = OldTemplate ? OldTemplate->getTemplatedDecl() : nullptr;
3593 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3594 if (checkUsingShadowRedecl<VarTemplateDecl>(*this, Shadow, NewTemplate))
3595 return New->setInvalidDecl();
3597 Old = dyn_cast<VarDecl>(Previous.getFoundDecl());
3600 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3601 if (checkUsingShadowRedecl<VarDecl>(*this, Shadow, New))
3602 return New->setInvalidDecl();
3606 Diag(New->getLocation(), diag::err_redefinition_different_kind)
3607 << New->getDeclName();
3608 Diag(Previous.getRepresentativeDecl()->getLocation(),
3609 diag::note_previous_definition);
3610 return New->setInvalidDecl();
3613 // Ensure the template parameters are compatible.
3615 !TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
3616 OldTemplate->getTemplateParameters(),
3617 /*Complain=*/true, TPL_TemplateMatch))
3618 return New->setInvalidDecl();
3620 // C++ [class.mem]p1:
3621 // A member shall not be declared twice in the member-specification [...]
3623 // Here, we need only consider static data members.
3624 if (Old->isStaticDataMember() && !New->isOutOfLine()) {
3625 Diag(New->getLocation(), diag::err_duplicate_member)
3626 << New->getIdentifier();
3627 Diag(Old->getLocation(), diag::note_previous_declaration);
3628 New->setInvalidDecl();
3631 mergeDeclAttributes(New, Old);
3632 // Warn if an already-declared variable is made a weak_import in a subsequent
3634 if (New->hasAttr<WeakImportAttr>() &&
3635 Old->getStorageClass() == SC_None &&
3636 !Old->hasAttr<WeakImportAttr>()) {
3637 Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName();
3638 Diag(Old->getLocation(), diag::note_previous_definition);
3639 // Remove weak_import attribute on new declaration.
3640 New->dropAttr<WeakImportAttr>();
3643 if (New->hasAttr<InternalLinkageAttr>() &&
3644 !Old->hasAttr<InternalLinkageAttr>()) {
3645 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
3646 << New->getDeclName();
3647 Diag(Old->getLocation(), diag::note_previous_definition);
3648 New->dropAttr<InternalLinkageAttr>();
3652 VarDecl *MostRecent = Old->getMostRecentDecl();
3653 if (MostRecent != Old) {
3654 MergeVarDeclTypes(New, MostRecent,
3655 mergeTypeWithPrevious(*this, New, MostRecent, Previous));
3656 if (New->isInvalidDecl())
3660 MergeVarDeclTypes(New, Old, mergeTypeWithPrevious(*this, New, Old, Previous));
3661 if (New->isInvalidDecl())
3664 diag::kind PrevDiag;
3665 SourceLocation OldLocation;
3666 std::tie(PrevDiag, OldLocation) =
3667 getNoteDiagForInvalidRedeclaration(Old, New);
3669 // [dcl.stc]p8: Check if we have a non-static decl followed by a static.
3670 if (New->getStorageClass() == SC_Static &&
3671 !New->isStaticDataMember() &&
3672 Old->hasExternalFormalLinkage()) {
3673 if (getLangOpts().MicrosoftExt) {
3674 Diag(New->getLocation(), diag::ext_static_non_static)
3675 << New->getDeclName();
3676 Diag(OldLocation, PrevDiag);
3678 Diag(New->getLocation(), diag::err_static_non_static)
3679 << New->getDeclName();
3680 Diag(OldLocation, PrevDiag);
3681 return New->setInvalidDecl();
3685 // For an identifier declared with the storage-class specifier
3686 // extern in a scope in which a prior declaration of that
3687 // identifier is visible,23) if the prior declaration specifies
3688 // internal or external linkage, the linkage of the identifier at
3689 // the later declaration is the same as the linkage specified at
3690 // the prior declaration. If no prior declaration is visible, or
3691 // if the prior declaration specifies no linkage, then the
3692 // identifier has external linkage.
3693 if (New->hasExternalStorage() && Old->hasLinkage())
3695 else if (New->getCanonicalDecl()->getStorageClass() != SC_Static &&
3696 !New->isStaticDataMember() &&
3697 Old->getCanonicalDecl()->getStorageClass() == SC_Static) {
3698 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName();
3699 Diag(OldLocation, PrevDiag);
3700 return New->setInvalidDecl();
3703 // Check if extern is followed by non-extern and vice-versa.
3704 if (New->hasExternalStorage() &&
3705 !Old->hasLinkage() && Old->isLocalVarDeclOrParm()) {
3706 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName();
3707 Diag(OldLocation, PrevDiag);
3708 return New->setInvalidDecl();
3710 if (Old->hasLinkage() && New->isLocalVarDeclOrParm() &&
3711 !New->hasExternalStorage()) {
3712 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName();
3713 Diag(OldLocation, PrevDiag);
3714 return New->setInvalidDecl();
3717 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup.
3719 // FIXME: The test for external storage here seems wrong? We still
3720 // need to check for mismatches.
3721 if (!New->hasExternalStorage() && !New->isFileVarDecl() &&
3722 // Don't complain about out-of-line definitions of static members.
3723 !(Old->getLexicalDeclContext()->isRecord() &&
3724 !New->getLexicalDeclContext()->isRecord())) {
3725 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName();
3726 Diag(OldLocation, PrevDiag);
3727 return New->setInvalidDecl();
3730 if (New->isInline() && !Old->getMostRecentDecl()->isInline()) {
3731 if (VarDecl *Def = Old->getDefinition()) {
3732 // C++1z [dcl.fcn.spec]p4:
3733 // If the definition of a variable appears in a translation unit before
3734 // its first declaration as inline, the program is ill-formed.
3735 Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
3736 Diag(Def->getLocation(), diag::note_previous_definition);
3740 // If this redeclaration makes the function inline, we may need to add it to
3741 // UndefinedButUsed.
3742 if (!Old->isInline() && New->isInline() && Old->isUsed(false) &&
3743 !Old->getDefinition() && !New->isThisDeclarationADefinition())
3744 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
3747 if (New->getTLSKind() != Old->getTLSKind()) {
3748 if (!Old->getTLSKind()) {
3749 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName();
3750 Diag(OldLocation, PrevDiag);
3751 } else if (!New->getTLSKind()) {
3752 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName();
3753 Diag(OldLocation, PrevDiag);
3755 // Do not allow redeclaration to change the variable between requiring
3756 // static and dynamic initialization.
3757 // FIXME: GCC allows this, but uses the TLS keyword on the first
3758 // declaration to determine the kind. Do we need to be compatible here?
3759 Diag(New->getLocation(), diag::err_thread_thread_different_kind)
3760 << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic);
3761 Diag(OldLocation, PrevDiag);
3765 // C++ doesn't have tentative definitions, so go right ahead and check here.
3766 if (getLangOpts().CPlusPlus &&
3767 New->isThisDeclarationADefinition() == VarDecl::Definition) {
3768 if (Old->isStaticDataMember() && Old->getCanonicalDecl()->isInline() &&
3769 Old->getCanonicalDecl()->isConstexpr()) {
3770 // This definition won't be a definition any more once it's been merged.
3771 Diag(New->getLocation(),
3772 diag::warn_deprecated_redundant_constexpr_static_def);
3773 } else if (VarDecl *Def = Old->getDefinition()) {
3774 if (checkVarDeclRedefinition(Def, New))
3779 if (haveIncompatibleLanguageLinkages(Old, New)) {
3780 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3781 Diag(OldLocation, PrevDiag);
3782 New->setInvalidDecl();
3786 // Merge "used" flag.
3787 if (Old->getMostRecentDecl()->isUsed(false))
3790 // Keep a chain of previous declarations.
3791 New->setPreviousDecl(Old);
3793 NewTemplate->setPreviousDecl(OldTemplate);
3795 // Inherit access appropriately.
3796 New->setAccess(Old->getAccess());
3798 NewTemplate->setAccess(New->getAccess());
3800 if (Old->isInline())
3801 New->setImplicitlyInline();
3804 /// We've just determined that \p Old and \p New both appear to be definitions
3805 /// of the same variable. Either diagnose or fix the problem.
3806 bool Sema::checkVarDeclRedefinition(VarDecl *Old, VarDecl *New) {
3807 if (!hasVisibleDefinition(Old) &&
3808 (New->getFormalLinkage() == InternalLinkage ||
3810 New->getDescribedVarTemplate() ||
3811 New->getNumTemplateParameterLists() ||
3812 New->getDeclContext()->isDependentContext())) {
3813 // The previous definition is hidden, and multiple definitions are
3814 // permitted (in separate TUs). Demote this to a declaration.
3815 New->demoteThisDefinitionToDeclaration();
3817 // Make the canonical definition visible.
3818 if (auto *OldTD = Old->getDescribedVarTemplate())
3819 makeMergedDefinitionVisible(OldTD, New->getLocation());
3820 makeMergedDefinitionVisible(Old, New->getLocation());
3823 Diag(New->getLocation(), diag::err_redefinition) << New;
3824 Diag(Old->getLocation(), diag::note_previous_definition);
3825 New->setInvalidDecl();
3830 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3831 /// no declarator (e.g. "struct foo;") is parsed.
3833 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3834 RecordDecl *&AnonRecord) {
3835 return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg(), false,
3839 // The MS ABI changed between VS2013 and VS2015 with regard to numbers used to
3840 // disambiguate entities defined in different scopes.
3841 // While the VS2015 ABI fixes potential miscompiles, it is also breaks
3843 // We will pick our mangling number depending on which version of MSVC is being
3845 static unsigned getMSManglingNumber(const LangOptions &LO, Scope *S) {
3846 return LO.isCompatibleWithMSVC(LangOptions::MSVC2015)
3847 ? S->getMSCurManglingNumber()
3848 : S->getMSLastManglingNumber();
3851 void Sema::handleTagNumbering(const TagDecl *Tag, Scope *TagScope) {
3852 if (!Context.getLangOpts().CPlusPlus)
3855 if (isa<CXXRecordDecl>(Tag->getParent())) {
3856 // If this tag is the direct child of a class, number it if
3858 if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl())
3860 MangleNumberingContext &MCtx =
3861 Context.getManglingNumberContext(Tag->getParent());
3862 Context.setManglingNumber(
3863 Tag, MCtx.getManglingNumber(
3864 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3868 // If this tag isn't a direct child of a class, number it if it is local.
3869 Decl *ManglingContextDecl;
3870 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
3871 Tag->getDeclContext(), ManglingContextDecl)) {
3872 Context.setManglingNumber(
3873 Tag, MCtx->getManglingNumber(
3874 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3878 void Sema::setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,
3879 TypedefNameDecl *NewTD) {
3880 if (TagFromDeclSpec->isInvalidDecl())
3883 // Do nothing if the tag already has a name for linkage purposes.
3884 if (TagFromDeclSpec->hasNameForLinkage())
3887 // A well-formed anonymous tag must always be a TUK_Definition.
3888 assert(TagFromDeclSpec->isThisDeclarationADefinition());
3890 // The type must match the tag exactly; no qualifiers allowed.
3891 if (!Context.hasSameType(NewTD->getUnderlyingType(),
3892 Context.getTagDeclType(TagFromDeclSpec))) {
3893 if (getLangOpts().CPlusPlus)
3894 Context.addTypedefNameForUnnamedTagDecl(TagFromDeclSpec, NewTD);
3898 // If we've already computed linkage for the anonymous tag, then
3899 // adding a typedef name for the anonymous decl can change that
3900 // linkage, which might be a serious problem. Diagnose this as
3901 // unsupported and ignore the typedef name. TODO: we should
3902 // pursue this as a language defect and establish a formal rule
3903 // for how to handle it.
3904 if (TagFromDeclSpec->hasLinkageBeenComputed()) {
3905 Diag(NewTD->getLocation(), diag::err_typedef_changes_linkage);
3907 SourceLocation tagLoc = TagFromDeclSpec->getInnerLocStart();
3908 tagLoc = getLocForEndOfToken(tagLoc);
3910 llvm::SmallString<40> textToInsert;
3911 textToInsert += ' ';
3912 textToInsert += NewTD->getIdentifier()->getName();
3913 Diag(tagLoc, diag::note_typedef_changes_linkage)
3914 << FixItHint::CreateInsertion(tagLoc, textToInsert);
3918 // Otherwise, set this is the anon-decl typedef for the tag.
3919 TagFromDeclSpec->setTypedefNameForAnonDecl(NewTD);
3922 static unsigned GetDiagnosticTypeSpecifierID(DeclSpec::TST T) {
3924 case DeclSpec::TST_class:
3926 case DeclSpec::TST_struct:
3928 case DeclSpec::TST_interface:
3930 case DeclSpec::TST_union:
3932 case DeclSpec::TST_enum:
3935 llvm_unreachable("unexpected type specifier");
3939 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3940 /// no declarator (e.g. "struct foo;") is parsed. It also accepts template
3941 /// parameters to cope with template friend declarations.
3943 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3944 MultiTemplateParamsArg TemplateParams,
3945 bool IsExplicitInstantiation,
3946 RecordDecl *&AnonRecord) {
3947 Decl *TagD = nullptr;
3948 TagDecl *Tag = nullptr;
3949 if (DS.getTypeSpecType() == DeclSpec::TST_class ||
3950 DS.getTypeSpecType() == DeclSpec::TST_struct ||
3951 DS.getTypeSpecType() == DeclSpec::TST_interface ||
3952 DS.getTypeSpecType() == DeclSpec::TST_union ||
3953 DS.getTypeSpecType() == DeclSpec::TST_enum) {
3954 TagD = DS.getRepAsDecl();
3956 if (!TagD) // We probably had an error
3959 // Note that the above type specs guarantee that the
3960 // type rep is a Decl, whereas in many of the others
3962 if (isa<TagDecl>(TagD))
3963 Tag = cast<TagDecl>(TagD);
3964 else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD))
3965 Tag = CTD->getTemplatedDecl();
3969 handleTagNumbering(Tag, S);
3970 Tag->setFreeStanding();
3971 if (Tag->isInvalidDecl())
3975 if (unsigned TypeQuals = DS.getTypeQualifiers()) {
3976 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object
3977 // or incomplete types shall not be restrict-qualified."
3978 if (TypeQuals & DeclSpec::TQ_restrict)
3979 Diag(DS.getRestrictSpecLoc(),
3980 diag::err_typecheck_invalid_restrict_not_pointer_noarg)
3981 << DS.getSourceRange();
3984 if (DS.isInlineSpecified())
3985 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
3986 << getLangOpts().CPlusPlus1z;
3988 if (DS.isConstexprSpecified()) {
3989 // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations
3990 // and definitions of functions and variables.
3992 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag)
3993 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType());
3995 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_no_declarators);
3996 // Don't emit warnings after this error.
4000 if (DS.isConceptSpecified()) {
4001 // C++ Concepts TS [dcl.spec.concept]p1: A concept definition refers to
4002 // either a function concept and its definition or a variable concept and
4004 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
4008 DiagnoseFunctionSpecifiers(DS);
4010 if (DS.isFriendSpecified()) {
4011 // If we're dealing with a decl but not a TagDecl, assume that
4012 // whatever routines created it handled the friendship aspect.
4015 return ActOnFriendTypeDecl(S, DS, TemplateParams);
4018 const CXXScopeSpec &SS = DS.getTypeSpecScope();
4019 bool IsExplicitSpecialization =
4020 !TemplateParams.empty() && TemplateParams.back()->size() == 0;
4021 if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() &&
4022 !IsExplicitInstantiation && !IsExplicitSpecialization &&
4023 !isa<ClassTemplatePartialSpecializationDecl>(Tag)) {
4024 // Per C++ [dcl.type.elab]p1, a class declaration cannot have a
4025 // nested-name-specifier unless it is an explicit instantiation
4026 // or an explicit specialization.
4028 // FIXME: We allow class template partial specializations here too, per the
4029 // obvious intent of DR1819.
4031 // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either.
4032 Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier)
4033 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) << SS.getRange();
4037 // Track whether this decl-specifier declares anything.
4038 bool DeclaresAnything = true;
4040 // Handle anonymous struct definitions.
4041 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
4042 if (!Record->getDeclName() && Record->isCompleteDefinition() &&
4043 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) {
4044 if (getLangOpts().CPlusPlus ||
4045 Record->getDeclContext()->isRecord()) {
4046 // If CurContext is a DeclContext that can contain statements,
4047 // RecursiveASTVisitor won't visit the decls that
4048 // BuildAnonymousStructOrUnion() will put into CurContext.
4049 // Also store them here so that they can be part of the
4050 // DeclStmt that gets created in this case.
4051 // FIXME: Also return the IndirectFieldDecls created by
4052 // BuildAnonymousStructOr union, for the same reason?
4053 if (CurContext->isFunctionOrMethod())
4054 AnonRecord = Record;
4055 return BuildAnonymousStructOrUnion(S, DS, AS, Record,
4056 Context.getPrintingPolicy());
4059 DeclaresAnything = false;
4064 // A struct-declaration that does not declare an anonymous structure or
4065 // anonymous union shall contain a struct-declarator-list.
4067 // This rule also existed in C89 and C99; the grammar for struct-declaration
4068 // did not permit a struct-declaration without a struct-declarator-list.
4069 if (!getLangOpts().CPlusPlus && CurContext->isRecord() &&
4070 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) {
4071 // Check for Microsoft C extension: anonymous struct/union member.
4072 // Handle 2 kinds of anonymous struct/union:
4076 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct.
4077 // UNION_TYPE; <- where UNION_TYPE is a typedef union.
4078 if ((Tag && Tag->getDeclName()) ||
4079 DS.getTypeSpecType() == DeclSpec::TST_typename) {
4080 RecordDecl *Record = nullptr;
4082 Record = dyn_cast<RecordDecl>(Tag);
4083 else if (const RecordType *RT =
4084 DS.getRepAsType().get()->getAsStructureType())
4085 Record = RT->getDecl();
4086 else if (const RecordType *UT = DS.getRepAsType().get()->getAsUnionType())
4087 Record = UT->getDecl();
4089 if (Record && getLangOpts().MicrosoftExt) {
4090 Diag(DS.getLocStart(), diag::ext_ms_anonymous_record)
4091 << Record->isUnion() << DS.getSourceRange();
4092 return BuildMicrosoftCAnonymousStruct(S, DS, Record);
4095 DeclaresAnything = false;
4099 // Skip all the checks below if we have a type error.
4100 if (DS.getTypeSpecType() == DeclSpec::TST_error ||
4101 (TagD && TagD->isInvalidDecl()))
4104 if (getLangOpts().CPlusPlus &&
4105 DS.getStorageClassSpec() != DeclSpec::SCS_typedef)
4106 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag))
4107 if (Enum->enumerator_begin() == Enum->enumerator_end() &&
4108 !Enum->getIdentifier() && !Enum->isInvalidDecl())
4109 DeclaresAnything = false;
4111 if (!DS.isMissingDeclaratorOk()) {
4112 // Customize diagnostic for a typedef missing a name.
4113 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
4114 Diag(DS.getLocStart(), diag::ext_typedef_without_a_name)
4115 << DS.getSourceRange();
4117 DeclaresAnything = false;
4120 if (DS.isModulePrivateSpecified() &&
4121 Tag && Tag->getDeclContext()->isFunctionOrMethod())
4122 Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class)
4123 << Tag->getTagKind()
4124 << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc());
4126 ActOnDocumentableDecl(TagD);
4129 // A declaration [...] shall declare at least a declarator [...], a tag,
4130 // or the members of an enumeration.
4132 // [If there are no declarators], and except for the declaration of an
4133 // unnamed bit-field, the decl-specifier-seq shall introduce one or more
4134 // names into the program, or shall redeclare a name introduced by a
4135 // previous declaration.
4136 if (!DeclaresAnything) {
4137 // In C, we allow this as a (popular) extension / bug. Don't bother
4138 // producing further diagnostics for redundant qualifiers after this.
4139 Diag(DS.getLocStart(), diag::ext_no_declarators) << DS.getSourceRange();
4144 // If a storage-class-specifier appears in a decl-specifier-seq, [...] the
4145 // init-declarator-list of the declaration shall not be empty.
4146 // C++ [dcl.fct.spec]p1:
4147 // If a cv-qualifier appears in a decl-specifier-seq, the
4148 // init-declarator-list of the declaration shall not be empty.
4150 // Spurious qualifiers here appear to be valid in C.
4151 unsigned DiagID = diag::warn_standalone_specifier;
4152 if (getLangOpts().CPlusPlus)
4153 DiagID = diag::ext_standalone_specifier;
4155 // Note that a linkage-specification sets a storage class, but
4156 // 'extern "C" struct foo;' is actually valid and not theoretically
4158 if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
4159 if (SCS == DeclSpec::SCS_mutable)
4160 // Since mutable is not a viable storage class specifier in C, there is
4161 // no reason to treat it as an extension. Instead, diagnose as an error.
4162 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_nonmember);
4163 else if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef)
4164 Diag(DS.getStorageClassSpecLoc(), DiagID)
4165 << DeclSpec::getSpecifierName(SCS);
4168 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
4169 Diag(DS.getThreadStorageClassSpecLoc(), DiagID)
4170 << DeclSpec::getSpecifierName(TSCS);
4171 if (DS.getTypeQualifiers()) {
4172 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4173 Diag(DS.getConstSpecLoc(), DiagID) << "const";
4174 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4175 Diag(DS.getConstSpecLoc(), DiagID) << "volatile";
4176 // Restrict is covered above.
4177 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4178 Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic";
4179 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4180 Diag(DS.getUnalignedSpecLoc(), DiagID) << "__unaligned";
4183 // Warn about ignored type attributes, for example:
4184 // __attribute__((aligned)) struct A;
4185 // Attributes should be placed after tag to apply to type declaration.
4186 if (!DS.getAttributes().empty()) {
4187 DeclSpec::TST TypeSpecType = DS.getTypeSpecType();
4188 if (TypeSpecType == DeclSpec::TST_class ||
4189 TypeSpecType == DeclSpec::TST_struct ||
4190 TypeSpecType == DeclSpec::TST_interface ||
4191 TypeSpecType == DeclSpec::TST_union ||
4192 TypeSpecType == DeclSpec::TST_enum) {
4193 for (AttributeList* attrs = DS.getAttributes().getList(); attrs;
4194 attrs = attrs->getNext())
4195 Diag(attrs->getLoc(), diag::warn_declspec_attribute_ignored)
4196 << attrs->getName() << GetDiagnosticTypeSpecifierID(TypeSpecType);
4203 /// We are trying to inject an anonymous member into the given scope;
4204 /// check if there's an existing declaration that can't be overloaded.
4206 /// \return true if this is a forbidden redeclaration
4207 static bool CheckAnonMemberRedeclaration(Sema &SemaRef,
4210 DeclarationName Name,
4211 SourceLocation NameLoc,
4213 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName,
4214 Sema::ForRedeclaration);
4215 if (!SemaRef.LookupName(R, S)) return false;
4217 // Pick a representative declaration.
4218 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl();
4219 assert(PrevDecl && "Expected a non-null Decl");
4221 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S))
4224 SemaRef.Diag(NameLoc, diag::err_anonymous_record_member_redecl)
4226 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
4231 /// InjectAnonymousStructOrUnionMembers - Inject the members of the
4232 /// anonymous struct or union AnonRecord into the owning context Owner
4233 /// and scope S. This routine will be invoked just after we realize
4234 /// that an unnamed union or struct is actually an anonymous union or
4241 /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and
4242 /// // f into the surrounding scope.x
4245 /// This routine is recursive, injecting the names of nested anonymous
4246 /// structs/unions into the owning context and scope as well.
4248 InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, DeclContext *Owner,
4249 RecordDecl *AnonRecord, AccessSpecifier AS,
4250 SmallVectorImpl<NamedDecl *> &Chaining) {
4251 bool Invalid = false;
4253 // Look every FieldDecl and IndirectFieldDecl with a name.
4254 for (auto *D : AnonRecord->decls()) {
4255 if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) &&
4256 cast<NamedDecl>(D)->getDeclName()) {
4257 ValueDecl *VD = cast<ValueDecl>(D);
4258 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(),
4260 AnonRecord->isUnion())) {
4261 // C++ [class.union]p2:
4262 // The names of the members of an anonymous union shall be
4263 // distinct from the names of any other entity in the
4264 // scope in which the anonymous union is declared.
4267 // C++ [class.union]p2:
4268 // For the purpose of name lookup, after the anonymous union
4269 // definition, the members of the anonymous union are
4270 // considered to have been defined in the scope in which the
4271 // anonymous union is declared.
4272 unsigned OldChainingSize = Chaining.size();
4273 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD))
4274 Chaining.append(IF->chain_begin(), IF->chain_end());
4276 Chaining.push_back(VD);
4278 assert(Chaining.size() >= 2);
4279 NamedDecl **NamedChain =
4280 new (SemaRef.Context)NamedDecl*[Chaining.size()];
4281 for (unsigned i = 0; i < Chaining.size(); i++)
4282 NamedChain[i] = Chaining[i];
4284 IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
4285 SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(),
4286 VD->getType(), {NamedChain, Chaining.size()});
4288 for (const auto *Attr : VD->attrs())
4289 IndirectField->addAttr(Attr->clone(SemaRef.Context));
4291 IndirectField->setAccess(AS);
4292 IndirectField->setImplicit();
4293 SemaRef.PushOnScopeChains(IndirectField, S);
4295 // That includes picking up the appropriate access specifier.
4296 if (AS != AS_none) IndirectField->setAccess(AS);
4298 Chaining.resize(OldChainingSize);
4306 /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to
4307 /// a VarDecl::StorageClass. Any error reporting is up to the caller:
4308 /// illegal input values are mapped to SC_None.
4310 StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) {
4311 DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec();
4312 assert(StorageClassSpec != DeclSpec::SCS_typedef &&
4313 "Parser allowed 'typedef' as storage class VarDecl.");
4314 switch (StorageClassSpec) {
4315 case DeclSpec::SCS_unspecified: return SC_None;
4316 case DeclSpec::SCS_extern:
4317 if (DS.isExternInLinkageSpec())
4320 case DeclSpec::SCS_static: return SC_Static;
4321 case DeclSpec::SCS_auto: return SC_Auto;
4322 case DeclSpec::SCS_register: return SC_Register;
4323 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
4324 // Illegal SCSs map to None: error reporting is up to the caller.
4325 case DeclSpec::SCS_mutable: // Fall through.
4326 case DeclSpec::SCS_typedef: return SC_None;
4328 llvm_unreachable("unknown storage class specifier");
4331 static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) {
4332 assert(Record->hasInClassInitializer());
4334 for (const auto *I : Record->decls()) {
4335 const auto *FD = dyn_cast<FieldDecl>(I);
4336 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
4337 FD = IFD->getAnonField();
4338 if (FD && FD->hasInClassInitializer())
4339 return FD->getLocation();
4342 llvm_unreachable("couldn't find in-class initializer");
4345 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4346 SourceLocation DefaultInitLoc) {
4347 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4350 S.Diag(DefaultInitLoc, diag::err_multiple_mem_union_initialization);
4351 S.Diag(findDefaultInitializer(Parent), diag::note_previous_initializer) << 0;
4354 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4355 CXXRecordDecl *AnonUnion) {
4356 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4359 checkDuplicateDefaultInit(S, Parent, findDefaultInitializer(AnonUnion));
4362 /// BuildAnonymousStructOrUnion - Handle the declaration of an
4363 /// anonymous structure or union. Anonymous unions are a C++ feature
4364 /// (C++ [class.union]) and a C11 feature; anonymous structures
4365 /// are a C11 feature and GNU C++ extension.
4366 Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
4369 const PrintingPolicy &Policy) {
4370 DeclContext *Owner = Record->getDeclContext();
4372 // Diagnose whether this anonymous struct/union is an extension.
4373 if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11)
4374 Diag(Record->getLocation(), diag::ext_anonymous_union);
4375 else if (!Record->isUnion() && getLangOpts().CPlusPlus)
4376 Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct);
4377 else if (!Record->isUnion() && !getLangOpts().C11)
4378 Diag(Record->getLocation(), diag::ext_c11_anonymous_struct);
4380 // C and C++ require different kinds of checks for anonymous
4382 bool Invalid = false;
4383 if (getLangOpts().CPlusPlus) {
4384 const char *PrevSpec = nullptr;
4386 if (Record->isUnion()) {
4387 // C++ [class.union]p6:
4388 // Anonymous unions declared in a named namespace or in the
4389 // global namespace shall be declared static.
4390 if (DS.getStorageClassSpec() != DeclSpec::SCS_static &&
4391 (isa<TranslationUnitDecl>(Owner) ||
4392 (isa<NamespaceDecl>(Owner) &&
4393 cast<NamespaceDecl>(Owner)->getDeclName()))) {
4394 Diag(Record->getLocation(), diag::err_anonymous_union_not_static)
4395 << FixItHint::CreateInsertion(Record->getLocation(), "static ");
4397 // Recover by adding 'static'.
4398 DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(),
4399 PrevSpec, DiagID, Policy);
4401 // C++ [class.union]p6:
4402 // A storage class is not allowed in a declaration of an
4403 // anonymous union in a class scope.
4404 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
4405 isa<RecordDecl>(Owner)) {
4406 Diag(DS.getStorageClassSpecLoc(),
4407 diag::err_anonymous_union_with_storage_spec)
4408 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
4410 // Recover by removing the storage specifier.
4411 DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified,
4413 PrevSpec, DiagID, Context.getPrintingPolicy());
4417 // Ignore const/volatile/restrict qualifiers.
4418 if (DS.getTypeQualifiers()) {
4419 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4420 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified)
4421 << Record->isUnion() << "const"
4422 << FixItHint::CreateRemoval(DS.getConstSpecLoc());
4423 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4424 Diag(DS.getVolatileSpecLoc(),
4425 diag::ext_anonymous_struct_union_qualified)
4426 << Record->isUnion() << "volatile"
4427 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc());
4428 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
4429 Diag(DS.getRestrictSpecLoc(),
4430 diag::ext_anonymous_struct_union_qualified)
4431 << Record->isUnion() << "restrict"
4432 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc());
4433 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4434 Diag(DS.getAtomicSpecLoc(),
4435 diag::ext_anonymous_struct_union_qualified)
4436 << Record->isUnion() << "_Atomic"
4437 << FixItHint::CreateRemoval(DS.getAtomicSpecLoc());
4438 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4439 Diag(DS.getUnalignedSpecLoc(),
4440 diag::ext_anonymous_struct_union_qualified)
4441 << Record->isUnion() << "__unaligned"
4442 << FixItHint::CreateRemoval(DS.getUnalignedSpecLoc());
4444 DS.ClearTypeQualifiers();
4447 // C++ [class.union]p2:
4448 // The member-specification of an anonymous union shall only
4449 // define non-static data members. [Note: nested types and
4450 // functions cannot be declared within an anonymous union. ]
4451 for (auto *Mem : Record->decls()) {
4452 if (auto *FD = dyn_cast<FieldDecl>(Mem)) {
4453 // C++ [class.union]p3:
4454 // An anonymous union shall not have private or protected
4455 // members (clause 11).
4456 assert(FD->getAccess() != AS_none);
4457 if (FD->getAccess() != AS_public) {
4458 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member)
4459 << Record->isUnion() << (FD->getAccess() == AS_protected);
4463 // C++ [class.union]p1
4464 // An object of a class with a non-trivial constructor, a non-trivial
4465 // copy constructor, a non-trivial destructor, or a non-trivial copy
4466 // assignment operator cannot be a member of a union, nor can an
4467 // array of such objects.
4468 if (CheckNontrivialField(FD))
4470 } else if (Mem->isImplicit()) {
4471 // Any implicit members are fine.
4472 } else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) {
4473 // This is a type that showed up in an
4474 // elaborated-type-specifier inside the anonymous struct or
4475 // union, but which actually declares a type outside of the
4476 // anonymous struct or union. It's okay.
4477 } else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) {
4478 if (!MemRecord->isAnonymousStructOrUnion() &&
4479 MemRecord->getDeclName()) {
4480 // Visual C++ allows type definition in anonymous struct or union.
4481 if (getLangOpts().MicrosoftExt)
4482 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type)
4483 << Record->isUnion();
4485 // This is a nested type declaration.
4486 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type)
4487 << Record->isUnion();
4491 // This is an anonymous type definition within another anonymous type.
4492 // This is a popular extension, provided by Plan9, MSVC and GCC, but
4493 // not part of standard C++.
4494 Diag(MemRecord->getLocation(),
4495 diag::ext_anonymous_record_with_anonymous_type)
4496 << Record->isUnion();
4498 } else if (isa<AccessSpecDecl>(Mem)) {
4499 // Any access specifier is fine.
4500 } else if (isa<StaticAssertDecl>(Mem)) {
4501 // In C++1z, static_assert declarations are also fine.
4503 // We have something that isn't a non-static data
4504 // member. Complain about it.
4505 unsigned DK = diag::err_anonymous_record_bad_member;
4506 if (isa<TypeDecl>(Mem))
4507 DK = diag::err_anonymous_record_with_type;
4508 else if (isa<FunctionDecl>(Mem))
4509 DK = diag::err_anonymous_record_with_function;
4510 else if (isa<VarDecl>(Mem))
4511 DK = diag::err_anonymous_record_with_static;
4513 // Visual C++ allows type definition in anonymous struct or union.
4514 if (getLangOpts().MicrosoftExt &&
4515 DK == diag::err_anonymous_record_with_type)
4516 Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type)
4517 << Record->isUnion();
4519 Diag(Mem->getLocation(), DK) << Record->isUnion();
4525 // C++11 [class.union]p8 (DR1460):
4526 // At most one variant member of a union may have a
4527 // brace-or-equal-initializer.
4528 if (cast<CXXRecordDecl>(Record)->hasInClassInitializer() &&
4530 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Owner),
4531 cast<CXXRecordDecl>(Record));
4534 if (!Record->isUnion() && !Owner->isRecord()) {
4535 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member)
4536 << getLangOpts().CPlusPlus;
4540 // Mock up a declarator.
4541 Declarator Dc(DS, Declarator::MemberContext);
4542 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4543 assert(TInfo && "couldn't build declarator info for anonymous struct/union");
4545 // Create a declaration for this anonymous struct/union.
4546 NamedDecl *Anon = nullptr;
4547 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) {
4548 Anon = FieldDecl::Create(Context, OwningClass,
4550 Record->getLocation(),
4551 /*IdentifierInfo=*/nullptr,
4552 Context.getTypeDeclType(Record),
4554 /*BitWidth=*/nullptr, /*Mutable=*/false,
4555 /*InitStyle=*/ICIS_NoInit);
4556 Anon->setAccess(AS);
4557 if (getLangOpts().CPlusPlus)
4558 FieldCollector->Add(cast<FieldDecl>(Anon));
4560 DeclSpec::SCS SCSpec = DS.getStorageClassSpec();
4561 StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS);
4562 if (SCSpec == DeclSpec::SCS_mutable) {
4563 // mutable can only appear on non-static class members, so it's always
4565 Diag(Record->getLocation(), diag::err_mutable_nonmember);
4570 Anon = VarDecl::Create(Context, Owner,
4572 Record->getLocation(), /*IdentifierInfo=*/nullptr,
4573 Context.getTypeDeclType(Record),
4576 // Default-initialize the implicit variable. This initialization will be
4577 // trivial in almost all cases, except if a union member has an in-class
4579 // union { int n = 0; };
4580 ActOnUninitializedDecl(Anon);
4582 Anon->setImplicit();
4584 // Mark this as an anonymous struct/union type.
4585 Record->setAnonymousStructOrUnion(true);
4587 // Add the anonymous struct/union object to the current
4588 // context. We'll be referencing this object when we refer to one of
4590 Owner->addDecl(Anon);
4592 // Inject the members of the anonymous struct/union into the owning
4593 // context and into the identifier resolver chain for name lookup
4595 SmallVector<NamedDecl*, 2> Chain;
4596 Chain.push_back(Anon);
4598 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, Chain))
4601 if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) {
4602 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
4603 Decl *ManglingContextDecl;
4604 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
4605 NewVD->getDeclContext(), ManglingContextDecl)) {
4606 Context.setManglingNumber(
4607 NewVD, MCtx->getManglingNumber(
4608 NewVD, getMSManglingNumber(getLangOpts(), S)));
4609 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
4615 Anon->setInvalidDecl();
4620 /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an
4621 /// Microsoft C anonymous structure.
4622 /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx
4625 /// struct A { int a; };
4626 /// struct B { struct A; int b; };
4633 Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
4634 RecordDecl *Record) {
4635 assert(Record && "expected a record!");
4637 // Mock up a declarator.
4638 Declarator Dc(DS, Declarator::TypeNameContext);
4639 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4640 assert(TInfo && "couldn't build declarator info for anonymous struct");
4642 auto *ParentDecl = cast<RecordDecl>(CurContext);
4643 QualType RecTy = Context.getTypeDeclType(Record);
4645 // Create a declaration for this anonymous struct.
4646 NamedDecl *Anon = FieldDecl::Create(Context,
4650 /*IdentifierInfo=*/nullptr,
4653 /*BitWidth=*/nullptr, /*Mutable=*/false,
4654 /*InitStyle=*/ICIS_NoInit);
4655 Anon->setImplicit();
4657 // Add the anonymous struct object to the current context.
4658 CurContext->addDecl(Anon);
4660 // Inject the members of the anonymous struct into the current
4661 // context and into the identifier resolver chain for name lookup
4663 SmallVector<NamedDecl*, 2> Chain;
4664 Chain.push_back(Anon);
4666 RecordDecl *RecordDef = Record->getDefinition();
4667 if (RequireCompleteType(Anon->getLocation(), RecTy,
4668 diag::err_field_incomplete) ||
4669 InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef,
4671 Anon->setInvalidDecl();
4672 ParentDecl->setInvalidDecl();
4678 /// GetNameForDeclarator - Determine the full declaration name for the
4679 /// given Declarator.
4680 DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) {
4681 return GetNameFromUnqualifiedId(D.getName());
4684 /// \brief Retrieves the declaration name from a parsed unqualified-id.
4686 Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
4687 DeclarationNameInfo NameInfo;
4688 NameInfo.setLoc(Name.StartLocation);
4690 switch (Name.getKind()) {
4692 case UnqualifiedId::IK_ImplicitSelfParam:
4693 case UnqualifiedId::IK_Identifier:
4694 NameInfo.setName(Name.Identifier);
4695 NameInfo.setLoc(Name.StartLocation);
4698 case UnqualifiedId::IK_DeductionGuideName: {
4699 // C++ [temp.deduct.guide]p3:
4700 // The simple-template-id shall name a class template specialization.
4701 // The template-name shall be the same identifier as the template-name
4702 // of the simple-template-id.
4703 // These together intend to imply that the template-name shall name a
4705 // FIXME: template<typename T> struct X {};
4706 // template<typename T> using Y = X<T>;
4707 // Y(int) -> Y<int>;
4708 // satisfies these rules but does not name a class template.
4709 TemplateName TN = Name.TemplateName.get().get();
4710 auto *Template = TN.getAsTemplateDecl();
4711 if (!Template || !isa<ClassTemplateDecl>(Template)) {
4712 Diag(Name.StartLocation,
4713 diag::err_deduction_guide_name_not_class_template)
4714 << (int)getTemplateNameKindForDiagnostics(TN) << TN;
4716 Diag(Template->getLocation(), diag::note_template_decl_here);
4717 return DeclarationNameInfo();
4721 Context.DeclarationNames.getCXXDeductionGuideName(Template));
4722 NameInfo.setLoc(Name.StartLocation);
4726 case UnqualifiedId::IK_OperatorFunctionId:
4727 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName(
4728 Name.OperatorFunctionId.Operator));
4729 NameInfo.setLoc(Name.StartLocation);
4730 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc
4731 = Name.OperatorFunctionId.SymbolLocations[0];
4732 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc
4733 = Name.EndLocation.getRawEncoding();
4736 case UnqualifiedId::IK_LiteralOperatorId:
4737 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName(
4739 NameInfo.setLoc(Name.StartLocation);
4740 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation);
4743 case UnqualifiedId::IK_ConversionFunctionId: {
4744 TypeSourceInfo *TInfo;
4745 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo);
4747 return DeclarationNameInfo();
4748 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName(
4749 Context.getCanonicalType(Ty)));
4750 NameInfo.setLoc(Name.StartLocation);
4751 NameInfo.setNamedTypeInfo(TInfo);
4755 case UnqualifiedId::IK_ConstructorName: {
4756 TypeSourceInfo *TInfo;
4757 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo);
4759 return DeclarationNameInfo();
4760 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4761 Context.getCanonicalType(Ty)));
4762 NameInfo.setLoc(Name.StartLocation);
4763 NameInfo.setNamedTypeInfo(TInfo);
4767 case UnqualifiedId::IK_ConstructorTemplateId: {
4768 // In well-formed code, we can only have a constructor
4769 // template-id that refers to the current context, so go there
4770 // to find the actual type being constructed.
4771 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext);
4772 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name)
4773 return DeclarationNameInfo();
4775 // Determine the type of the class being constructed.
4776 QualType CurClassType = Context.getTypeDeclType(CurClass);
4778 // FIXME: Check two things: that the template-id names the same type as
4779 // CurClassType, and that the template-id does not occur when the name
4782 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4783 Context.getCanonicalType(CurClassType)));
4784 NameInfo.setLoc(Name.StartLocation);
4785 // FIXME: should we retrieve TypeSourceInfo?
4786 NameInfo.setNamedTypeInfo(nullptr);
4790 case UnqualifiedId::IK_DestructorName: {
4791 TypeSourceInfo *TInfo;
4792 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo);
4794 return DeclarationNameInfo();
4795 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName(
4796 Context.getCanonicalType(Ty)));
4797 NameInfo.setLoc(Name.StartLocation);
4798 NameInfo.setNamedTypeInfo(TInfo);
4802 case UnqualifiedId::IK_TemplateId: {
4803 TemplateName TName = Name.TemplateId->Template.get();
4804 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc;
4805 return Context.getNameForTemplate(TName, TNameLoc);
4808 } // switch (Name.getKind())
4810 llvm_unreachable("Unknown name kind");
4813 static QualType getCoreType(QualType Ty) {
4815 if (Ty->isPointerType() || Ty->isReferenceType())
4816 Ty = Ty->getPointeeType();
4817 else if (Ty->isArrayType())
4818 Ty = Ty->castAsArrayTypeUnsafe()->getElementType();
4820 return Ty.withoutLocalFastQualifiers();
4824 /// hasSimilarParameters - Determine whether the C++ functions Declaration
4825 /// and Definition have "nearly" matching parameters. This heuristic is
4826 /// used to improve diagnostics in the case where an out-of-line function
4827 /// definition doesn't match any declaration within the class or namespace.
4828 /// Also sets Params to the list of indices to the parameters that differ
4829 /// between the declaration and the definition. If hasSimilarParameters
4830 /// returns true and Params is empty, then all of the parameters match.
4831 static bool hasSimilarParameters(ASTContext &Context,
4832 FunctionDecl *Declaration,
4833 FunctionDecl *Definition,
4834 SmallVectorImpl<unsigned> &Params) {
4836 if (Declaration->param_size() != Definition->param_size())
4838 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) {
4839 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType();
4840 QualType DefParamTy = Definition->getParamDecl(Idx)->getType();
4842 // The parameter types are identical
4843 if (Context.hasSameType(DefParamTy, DeclParamTy))
4846 QualType DeclParamBaseTy = getCoreType(DeclParamTy);
4847 QualType DefParamBaseTy = getCoreType(DefParamTy);
4848 const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier();
4849 const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier();
4851 if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) ||
4852 (DeclTyName && DeclTyName == DefTyName))
4853 Params.push_back(Idx);
4854 else // The two parameters aren't even close
4861 /// NeedsRebuildingInCurrentInstantiation - Checks whether the given
4862 /// declarator needs to be rebuilt in the current instantiation.
4863 /// Any bits of declarator which appear before the name are valid for
4864 /// consideration here. That's specifically the type in the decl spec
4865 /// and the base type in any member-pointer chunks.
4866 static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D,
4867 DeclarationName Name) {
4868 // The types we specifically need to rebuild are:
4869 // - typenames, typeofs, and decltypes
4870 // - types which will become injected class names
4871 // Of course, we also need to rebuild any type referencing such a
4872 // type. It's safest to just say "dependent", but we call out a
4875 DeclSpec &DS = D.getMutableDeclSpec();
4876 switch (DS.getTypeSpecType()) {
4877 case DeclSpec::TST_typename:
4878 case DeclSpec::TST_typeofType:
4879 case DeclSpec::TST_underlyingType:
4880 case DeclSpec::TST_atomic: {
4881 // Grab the type from the parser.
4882 TypeSourceInfo *TSI = nullptr;
4883 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI);
4884 if (T.isNull() || !T->isDependentType()) break;
4886 // Make sure there's a type source info. This isn't really much
4887 // of a waste; most dependent types should have type source info
4888 // attached already.
4890 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc());
4892 // Rebuild the type in the current instantiation.
4893 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name);
4894 if (!TSI) return true;
4896 // Store the new type back in the decl spec.
4897 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI);
4898 DS.UpdateTypeRep(LocType);
4902 case DeclSpec::TST_decltype:
4903 case DeclSpec::TST_typeofExpr: {
4904 Expr *E = DS.getRepAsExpr();
4905 ExprResult Result = S.RebuildExprInCurrentInstantiation(E);
4906 if (Result.isInvalid()) return true;
4907 DS.UpdateExprRep(Result.get());
4912 // Nothing to do for these decl specs.
4916 // It doesn't matter what order we do this in.
4917 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
4918 DeclaratorChunk &Chunk = D.getTypeObject(I);
4920 // The only type information in the declarator which can come
4921 // before the declaration name is the base type of a member
4923 if (Chunk.Kind != DeclaratorChunk::MemberPointer)
4926 // Rebuild the scope specifier in-place.
4927 CXXScopeSpec &SS = Chunk.Mem.Scope();
4928 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS))
4935 Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) {
4936 D.setFunctionDefinitionKind(FDK_Declaration);
4937 Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg());
4939 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() &&
4940 Dcl && Dcl->getDeclContext()->isFileContext())
4941 Dcl->setTopLevelDeclInObjCContainer();
4943 if (getLangOpts().OpenCL)
4944 setCurrentOpenCLExtensionForDecl(Dcl);
4949 /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13:
4950 /// If T is the name of a class, then each of the following shall have a
4951 /// name different from T:
4952 /// - every static data member of class T;
4953 /// - every member function of class T
4954 /// - every member of class T that is itself a type;
4955 /// \returns true if the declaration name violates these rules.
4956 bool Sema::DiagnoseClassNameShadow(DeclContext *DC,
4957 DeclarationNameInfo NameInfo) {
4958 DeclarationName Name = NameInfo.getName();
4960 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC);
4961 while (Record && Record->isAnonymousStructOrUnion())
4962 Record = dyn_cast<CXXRecordDecl>(Record->getParent());
4963 if (Record && Record->getIdentifier() && Record->getDeclName() == Name) {
4964 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name;
4971 /// \brief Diagnose a declaration whose declarator-id has the given
4972 /// nested-name-specifier.
4974 /// \param SS The nested-name-specifier of the declarator-id.
4976 /// \param DC The declaration context to which the nested-name-specifier
4979 /// \param Name The name of the entity being declared.
4981 /// \param Loc The location of the name of the entity being declared.
4983 /// \returns true if we cannot safely recover from this error, false otherwise.
4984 bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
4985 DeclarationName Name,
4986 SourceLocation Loc) {
4987 DeclContext *Cur = CurContext;
4988 while (isa<LinkageSpecDecl>(Cur) || isa<CapturedDecl>(Cur))
4989 Cur = Cur->getParent();
4991 // If the user provided a superfluous scope specifier that refers back to the
4992 // class in which the entity is already declared, diagnose and ignore it.
4998 // Note, it was once ill-formed to give redundant qualification in all
4999 // contexts, but that rule was removed by DR482.
5000 if (Cur->Equals(DC)) {
5001 if (Cur->isRecord()) {
5002 Diag(Loc, LangOpts.MicrosoftExt ? diag::warn_member_extra_qualification
5003 : diag::err_member_extra_qualification)
5004 << Name << FixItHint::CreateRemoval(SS.getRange());
5007 Diag(Loc, diag::warn_namespace_member_extra_qualification) << Name;
5012 // Check whether the qualifying scope encloses the scope of the original
5014 if (!Cur->Encloses(DC)) {
5015 if (Cur->isRecord())
5016 Diag(Loc, diag::err_member_qualification)
5017 << Name << SS.getRange();
5018 else if (isa<TranslationUnitDecl>(DC))
5019 Diag(Loc, diag::err_invalid_declarator_global_scope)
5020 << Name << SS.getRange();
5021 else if (isa<FunctionDecl>(Cur))
5022 Diag(Loc, diag::err_invalid_declarator_in_function)
5023 << Name << SS.getRange();
5024 else if (isa<BlockDecl>(Cur))
5025 Diag(Loc, diag::err_invalid_declarator_in_block)
5026 << Name << SS.getRange();
5028 Diag(Loc, diag::err_invalid_declarator_scope)
5029 << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange();
5034 if (Cur->isRecord()) {
5035 // Cannot qualify members within a class.
5036 Diag(Loc, diag::err_member_qualification)
5037 << Name << SS.getRange();
5040 // C++ constructors and destructors with incorrect scopes can break
5041 // our AST invariants by having the wrong underlying types. If
5042 // that's the case, then drop this declaration entirely.
5043 if ((Name.getNameKind() == DeclarationName::CXXConstructorName ||
5044 Name.getNameKind() == DeclarationName::CXXDestructorName) &&
5045 !Context.hasSameType(Name.getCXXNameType(),
5046 Context.getTypeDeclType(cast<CXXRecordDecl>(Cur))))
5052 // C++11 [dcl.meaning]p1:
5053 // [...] "The nested-name-specifier of the qualified declarator-id shall
5054 // not begin with a decltype-specifer"
5055 NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data());
5056 while (SpecLoc.getPrefix())
5057 SpecLoc = SpecLoc.getPrefix();
5058 if (dyn_cast_or_null<DecltypeType>(
5059 SpecLoc.getNestedNameSpecifier()->getAsType()))
5060 Diag(Loc, diag::err_decltype_in_declarator)
5061 << SpecLoc.getTypeLoc().getSourceRange();
5066 NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
5067 MultiTemplateParamsArg TemplateParamLists) {
5068 // TODO: consider using NameInfo for diagnostic.
5069 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
5070 DeclarationName Name = NameInfo.getName();
5072 // All of these full declarators require an identifier. If it doesn't have
5073 // one, the ParsedFreeStandingDeclSpec action should be used.
5074 if (D.isDecompositionDeclarator()) {
5075 return ActOnDecompositionDeclarator(S, D, TemplateParamLists);
5077 if (!D.isInvalidType()) // Reject this if we think it is valid.
5078 Diag(D.getDeclSpec().getLocStart(),
5079 diag::err_declarator_need_ident)
5080 << D.getDeclSpec().getSourceRange() << D.getSourceRange();
5082 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType))
5085 // The scope passed in may not be a decl scope. Zip up the scope tree until
5086 // we find one that is.
5087 while ((S->getFlags() & Scope::DeclScope) == 0 ||
5088 (S->getFlags() & Scope::TemplateParamScope) != 0)
5091 DeclContext *DC = CurContext;
5092 if (D.getCXXScopeSpec().isInvalid())
5094 else if (D.getCXXScopeSpec().isSet()) {
5095 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(),
5096 UPPC_DeclarationQualifier))
5099 bool EnteringContext = !D.getDeclSpec().isFriendSpecified();
5100 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext);
5101 if (!DC || isa<EnumDecl>(DC)) {
5102 // If we could not compute the declaration context, it's because the
5103 // declaration context is dependent but does not refer to a class,
5104 // class template, or class template partial specialization. Complain
5105 // and return early, to avoid the coming semantic disaster.
5106 Diag(D.getIdentifierLoc(),
5107 diag::err_template_qualified_declarator_no_match)
5108 << D.getCXXScopeSpec().getScopeRep()
5109 << D.getCXXScopeSpec().getRange();
5112 bool IsDependentContext = DC->isDependentContext();
5114 if (!IsDependentContext &&
5115 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC))
5118 // If a class is incomplete, do not parse entities inside it.
5119 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) {
5120 Diag(D.getIdentifierLoc(),
5121 diag::err_member_def_undefined_record)
5122 << Name << DC << D.getCXXScopeSpec().getRange();
5125 if (!D.getDeclSpec().isFriendSpecified()) {
5126 if (diagnoseQualifiedDeclaration(D.getCXXScopeSpec(), DC,
5127 Name, D.getIdentifierLoc())) {
5135 // Check whether we need to rebuild the type of the given
5136 // declaration in the current instantiation.
5137 if (EnteringContext && IsDependentContext &&
5138 TemplateParamLists.size() != 0) {
5139 ContextRAII SavedContext(*this, DC);
5140 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name))
5145 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
5146 QualType R = TInfo->getType();
5148 if (!R->isFunctionType() && DiagnoseClassNameShadow(DC, NameInfo))
5149 // If this is a typedef, we'll end up spewing multiple diagnostics.
5150 // Just return early; it's safer. If this is a function, let the
5151 // "constructor cannot have a return type" diagnostic handle it.
5152 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
5155 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
5156 UPPC_DeclarationType))
5159 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
5162 // See if this is a redefinition of a variable in the same scope.
5163 if (!D.getCXXScopeSpec().isSet()) {
5164 bool IsLinkageLookup = false;
5165 bool CreateBuiltins = false;
5167 // If the declaration we're planning to build will be a function
5168 // or object with linkage, then look for another declaration with
5169 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6).
5171 // If the declaration we're planning to build will be declared with
5172 // external linkage in the translation unit, create any builtin with
5174 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
5176 else if (CurContext->isFunctionOrMethod() &&
5177 (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern ||
5178 R->isFunctionType())) {
5179 IsLinkageLookup = true;
5181 CurContext->getEnclosingNamespaceContext()->isTranslationUnit();
5182 } else if (CurContext->getRedeclContext()->isTranslationUnit() &&
5183 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
5184 CreateBuiltins = true;
5186 if (IsLinkageLookup)
5187 Previous.clear(LookupRedeclarationWithLinkage);
5189 LookupName(Previous, S, CreateBuiltins);
5190 } else { // Something like "int foo::x;"
5191 LookupQualifiedName(Previous, DC);
5193 // C++ [dcl.meaning]p1:
5194 // When the declarator-id is qualified, the declaration shall refer to a
5195 // previously declared member of the class or namespace to which the
5196 // qualifier refers (or, in the case of a namespace, of an element of the
5197 // inline namespace set of that namespace (7.3.1)) or to a specialization
5200 // Note that we already checked the context above, and that we do not have
5201 // enough information to make sure that Previous contains the declaration
5202 // we want to match. For example, given:
5209 // void X::f(int) { } // ill-formed
5211 // In this case, Previous will point to the overload set
5212 // containing the two f's declared in X, but neither of them
5215 // C++ [dcl.meaning]p1:
5216 // [...] the member shall not merely have been introduced by a
5217 // using-declaration in the scope of the class or namespace nominated by
5218 // the nested-name-specifier of the declarator-id.
5219 RemoveUsingDecls(Previous);
5222 if (Previous.isSingleResult() &&
5223 Previous.getFoundDecl()->isTemplateParameter()) {
5224 // Maybe we will complain about the shadowed template parameter.
5225 if (!D.isInvalidType())
5226 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
5227 Previous.getFoundDecl());
5229 // Just pretend that we didn't see the previous declaration.
5233 // In C++, the previous declaration we find might be a tag type
5234 // (class or enum). In this case, the new declaration will hide the
5235 // tag type. Note that this does does not apply if we're declaring a
5236 // typedef (C++ [dcl.typedef]p4).
5237 if (Previous.isSingleTagDecl() &&
5238 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef)
5241 // Check that there are no default arguments other than in the parameters
5242 // of a function declaration (C++ only).
5243 if (getLangOpts().CPlusPlus)
5244 CheckExtraCXXDefaultArguments(D);
5246 if (D.getDeclSpec().isConceptSpecified()) {
5247 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
5248 // applied only to the definition of a function template or variable
5249 // template, declared in namespace scope
5250 if (!TemplateParamLists.size()) {
5251 Diag(D.getDeclSpec().getConceptSpecLoc(),
5252 diag:: err_concept_wrong_decl_kind);
5256 if (!DC->getRedeclContext()->isFileContext()) {
5257 Diag(D.getIdentifierLoc(),
5258 diag::err_concept_decls_may_only_appear_in_namespace_scope);
5265 bool AddToScope = true;
5266 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
5267 if (TemplateParamLists.size()) {
5268 Diag(D.getIdentifierLoc(), diag::err_template_typedef);
5272 New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous);
5273 } else if (R->isFunctionType()) {
5274 New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous,
5278 New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists,
5285 // If this has an identifier and is not a function template specialization,
5286 // add it to the scope stack.
5287 if (New->getDeclName() && AddToScope) {
5288 // Only make a locally-scoped extern declaration visible if it is the first
5289 // declaration of this entity. Qualified lookup for such an entity should
5290 // only find this declaration if there is no visible declaration of it.
5291 bool AddToContext = !D.isRedeclaration() || !New->isLocalExternDecl();
5292 PushOnScopeChains(New, S, AddToContext);
5294 CurContext->addHiddenDecl(New);
5297 if (isInOpenMPDeclareTargetContext())
5298 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
5303 /// Helper method to turn variable array types into constant array
5304 /// types in certain situations which would otherwise be errors (for
5305 /// GCC compatibility).
5306 static QualType TryToFixInvalidVariablyModifiedType(QualType T,
5307 ASTContext &Context,
5308 bool &SizeIsNegative,
5309 llvm::APSInt &Oversized) {
5310 // This method tries to turn a variable array into a constant
5311 // array even when the size isn't an ICE. This is necessary
5312 // for compatibility with code that depends on gcc's buggy
5313 // constant expression folding, like struct {char x[(int)(char*)2];}
5314 SizeIsNegative = false;
5317 if (T->isDependentType())
5320 QualifierCollector Qs;
5321 const Type *Ty = Qs.strip(T);
5323 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) {
5324 QualType Pointee = PTy->getPointeeType();
5325 QualType FixedType =
5326 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative,
5328 if (FixedType.isNull()) return FixedType;
5329 FixedType = Context.getPointerType(FixedType);
5330 return Qs.apply(Context, FixedType);
5332 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) {
5333 QualType Inner = PTy->getInnerType();
5334 QualType FixedType =
5335 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative,
5337 if (FixedType.isNull()) return FixedType;
5338 FixedType = Context.getParenType(FixedType);
5339 return Qs.apply(Context, FixedType);
5342 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T);
5345 // FIXME: We should probably handle this case
5346 if (VLATy->getElementType()->isVariablyModifiedType())
5350 if (!VLATy->getSizeExpr() ||
5351 !VLATy->getSizeExpr()->EvaluateAsInt(Res, Context))
5354 // Check whether the array size is negative.
5355 if (Res.isSigned() && Res.isNegative()) {
5356 SizeIsNegative = true;
5360 // Check whether the array is too large to be addressed.
5361 unsigned ActiveSizeBits
5362 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(),
5364 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
5369 return Context.getConstantArrayType(VLATy->getElementType(),
5370 Res, ArrayType::Normal, 0);
5374 FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) {
5375 SrcTL = SrcTL.getUnqualifiedLoc();
5376 DstTL = DstTL.getUnqualifiedLoc();
5377 if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) {
5378 PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>();
5379 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(),
5380 DstPTL.getPointeeLoc());
5381 DstPTL.setStarLoc(SrcPTL.getStarLoc());
5384 if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) {
5385 ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>();
5386 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(),
5387 DstPTL.getInnerLoc());
5388 DstPTL.setLParenLoc(SrcPTL.getLParenLoc());
5389 DstPTL.setRParenLoc(SrcPTL.getRParenLoc());
5392 ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>();
5393 ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>();
5394 TypeLoc SrcElemTL = SrcATL.getElementLoc();
5395 TypeLoc DstElemTL = DstATL.getElementLoc();
5396 DstElemTL.initializeFullCopy(SrcElemTL);
5397 DstATL.setLBracketLoc(SrcATL.getLBracketLoc());
5398 DstATL.setSizeExpr(SrcATL.getSizeExpr());
5399 DstATL.setRBracketLoc(SrcATL.getRBracketLoc());
5402 /// Helper method to turn variable array types into constant array
5403 /// types in certain situations which would otherwise be errors (for
5404 /// GCC compatibility).
5405 static TypeSourceInfo*
5406 TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo,
5407 ASTContext &Context,
5408 bool &SizeIsNegative,
5409 llvm::APSInt &Oversized) {
5411 = TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context,
5412 SizeIsNegative, Oversized);
5413 if (FixedTy.isNull())
5415 TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy);
5416 FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(),
5417 FixedTInfo->getTypeLoc());
5421 /// \brief Register the given locally-scoped extern "C" declaration so
5422 /// that it can be found later for redeclarations. We include any extern "C"
5423 /// declaration that is not visible in the translation unit here, not just
5424 /// function-scope declarations.
5426 Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) {
5427 if (!getLangOpts().CPlusPlus &&
5428 ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit())
5429 // Don't need to track declarations in the TU in C.
5432 // Note that we have a locally-scoped external with this name.
5433 Context.getExternCContextDecl()->makeDeclVisibleInContext(ND);
5436 NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) {
5437 // FIXME: We can have multiple results via __attribute__((overloadable)).
5438 auto Result = Context.getExternCContextDecl()->lookup(Name);
5439 return Result.empty() ? nullptr : *Result.begin();
5442 /// \brief Diagnose function specifiers on a declaration of an identifier that
5443 /// does not identify a function.
5444 void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) {
5445 // FIXME: We should probably indicate the identifier in question to avoid
5446 // confusion for constructs like "virtual int a(), b;"
5447 if (DS.isVirtualSpecified())
5448 Diag(DS.getVirtualSpecLoc(),
5449 diag::err_virtual_non_function);
5451 if (DS.isExplicitSpecified())
5452 Diag(DS.getExplicitSpecLoc(),
5453 diag::err_explicit_non_function);
5455 if (DS.isNoreturnSpecified())
5456 Diag(DS.getNoreturnSpecLoc(),
5457 diag::err_noreturn_non_function);
5461 Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
5462 TypeSourceInfo *TInfo, LookupResult &Previous) {
5463 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1).
5464 if (D.getCXXScopeSpec().isSet()) {
5465 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator)
5466 << D.getCXXScopeSpec().getRange();
5468 // Pretend we didn't see the scope specifier.
5473 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5475 if (D.getDeclSpec().isInlineSpecified())
5476 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
5477 << getLangOpts().CPlusPlus1z;
5478 if (D.getDeclSpec().isConstexprSpecified())
5479 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr)
5481 if (D.getDeclSpec().isConceptSpecified())
5482 Diag(D.getDeclSpec().getConceptSpecLoc(),
5483 diag::err_concept_wrong_decl_kind);
5485 if (D.getName().Kind != UnqualifiedId::IK_Identifier) {
5486 if (D.getName().Kind == UnqualifiedId::IK_DeductionGuideName)
5487 Diag(D.getName().StartLocation,
5488 diag::err_deduction_guide_invalid_specifier)
5491 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier)
5492 << D.getName().getSourceRange();
5496 TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo);
5497 if (!NewTD) return nullptr;
5499 // Handle attributes prior to checking for duplicates in MergeVarDecl
5500 ProcessDeclAttributes(S, NewTD, D);
5502 CheckTypedefForVariablyModifiedType(S, NewTD);
5504 bool Redeclaration = D.isRedeclaration();
5505 NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration);
5506 D.setRedeclaration(Redeclaration);
5511 Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) {
5512 // C99 6.7.7p2: If a typedef name specifies a variably modified type
5513 // then it shall have block scope.
5514 // Note that variably modified types must be fixed before merging the decl so
5515 // that redeclarations will match.
5516 TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo();
5517 QualType T = TInfo->getType();
5518 if (T->isVariablyModifiedType()) {
5519 getCurFunction()->setHasBranchProtectedScope();
5521 if (S->getFnParent() == nullptr) {
5522 bool SizeIsNegative;
5523 llvm::APSInt Oversized;
5524 TypeSourceInfo *FixedTInfo =
5525 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
5529 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size);
5530 NewTD->setTypeSourceInfo(FixedTInfo);
5533 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size);
5534 else if (T->isVariableArrayType())
5535 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope);
5536 else if (Oversized.getBoolValue())
5537 Diag(NewTD->getLocation(), diag::err_array_too_large)
5538 << Oversized.toString(10);
5540 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope);
5541 NewTD->setInvalidDecl();
5547 /// ActOnTypedefNameDecl - Perform semantic checking for a declaration which
5548 /// declares a typedef-name, either using the 'typedef' type specifier or via
5549 /// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'.
5551 Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD,
5552 LookupResult &Previous, bool &Redeclaration) {
5554 // Find the shadowed declaration before filtering for scope.
5555 NamedDecl *ShadowedDecl = getShadowedDeclaration(NewTD, Previous);
5557 // Merge the decl with the existing one if appropriate. If the decl is
5558 // in an outer scope, it isn't the same thing.
5559 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/false,
5560 /*AllowInlineNamespace*/false);
5561 filterNonConflictingPreviousTypedefDecls(*this, NewTD, Previous);
5562 if (!Previous.empty()) {
5563 Redeclaration = true;
5564 MergeTypedefNameDecl(S, NewTD, Previous);
5567 if (ShadowedDecl && !Redeclaration)
5568 CheckShadow(NewTD, ShadowedDecl, Previous);
5570 // If this is the C FILE type, notify the AST context.
5571 if (IdentifierInfo *II = NewTD->getIdentifier())
5572 if (!NewTD->isInvalidDecl() &&
5573 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
5574 if (II->isStr("FILE"))
5575 Context.setFILEDecl(NewTD);
5576 else if (II->isStr("jmp_buf"))
5577 Context.setjmp_bufDecl(NewTD);
5578 else if (II->isStr("sigjmp_buf"))
5579 Context.setsigjmp_bufDecl(NewTD);
5580 else if (II->isStr("ucontext_t"))
5581 Context.setucontext_tDecl(NewTD);
5587 /// \brief Determines whether the given declaration is an out-of-scope
5588 /// previous declaration.
5590 /// This routine should be invoked when name lookup has found a
5591 /// previous declaration (PrevDecl) that is not in the scope where a
5592 /// new declaration by the same name is being introduced. If the new
5593 /// declaration occurs in a local scope, previous declarations with
5594 /// linkage may still be considered previous declarations (C99
5595 /// 6.2.2p4-5, C++ [basic.link]p6).
5597 /// \param PrevDecl the previous declaration found by name
5600 /// \param DC the context in which the new declaration is being
5603 /// \returns true if PrevDecl is an out-of-scope previous declaration
5604 /// for a new delcaration with the same name.
5606 isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC,
5607 ASTContext &Context) {
5611 if (!PrevDecl->hasLinkage())
5614 if (Context.getLangOpts().CPlusPlus) {
5615 // C++ [basic.link]p6:
5616 // If there is a visible declaration of an entity with linkage
5617 // having the same name and type, ignoring entities declared
5618 // outside the innermost enclosing namespace scope, the block
5619 // scope declaration declares that same entity and receives the
5620 // linkage of the previous declaration.
5621 DeclContext *OuterContext = DC->getRedeclContext();
5622 if (!OuterContext->isFunctionOrMethod())
5623 // This rule only applies to block-scope declarations.
5626 DeclContext *PrevOuterContext = PrevDecl->getDeclContext();
5627 if (PrevOuterContext->isRecord())
5628 // We found a member function: ignore it.
5631 // Find the innermost enclosing namespace for the new and
5632 // previous declarations.
5633 OuterContext = OuterContext->getEnclosingNamespaceContext();
5634 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext();
5636 // The previous declaration is in a different namespace, so it
5637 // isn't the same function.
5638 if (!OuterContext->Equals(PrevOuterContext))
5645 static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) {
5646 CXXScopeSpec &SS = D.getCXXScopeSpec();
5647 if (!SS.isSet()) return;
5648 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext()));
5651 bool Sema::inferObjCARCLifetime(ValueDecl *decl) {
5652 QualType type = decl->getType();
5653 Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime();
5654 if (lifetime == Qualifiers::OCL_Autoreleasing) {
5655 // Various kinds of declaration aren't allowed to be __autoreleasing.
5656 unsigned kind = -1U;
5657 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5658 if (var->hasAttr<BlocksAttr>())
5659 kind = 0; // __block
5660 else if (!var->hasLocalStorage())
5662 } else if (isa<ObjCIvarDecl>(decl)) {
5664 } else if (isa<FieldDecl>(decl)) {
5669 Diag(decl->getLocation(), diag::err_arc_autoreleasing_var)
5672 } else if (lifetime == Qualifiers::OCL_None) {
5673 // Try to infer lifetime.
5674 if (!type->isObjCLifetimeType())
5677 lifetime = type->getObjCARCImplicitLifetime();
5678 type = Context.getLifetimeQualifiedType(type, lifetime);
5679 decl->setType(type);
5682 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5683 // Thread-local variables cannot have lifetime.
5684 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone &&
5685 var->getTLSKind()) {
5686 Diag(var->getLocation(), diag::err_arc_thread_ownership)
5695 static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) {
5696 // Ensure that an auto decl is deduced otherwise the checks below might cache
5697 // the wrong linkage.
5698 assert(S.ParsingInitForAutoVars.count(&ND) == 0);
5700 // 'weak' only applies to declarations with external linkage.
5701 if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) {
5702 if (!ND.isExternallyVisible()) {
5703 S.Diag(Attr->getLocation(), diag::err_attribute_weak_static);
5704 ND.dropAttr<WeakAttr>();
5707 if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) {
5708 if (ND.isExternallyVisible()) {
5709 S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static);
5710 ND.dropAttr<WeakRefAttr>();
5711 ND.dropAttr<AliasAttr>();
5715 if (auto *VD = dyn_cast<VarDecl>(&ND)) {
5716 if (VD->hasInit()) {
5717 if (const auto *Attr = VD->getAttr<AliasAttr>()) {
5718 assert(VD->isThisDeclarationADefinition() &&
5719 !VD->isExternallyVisible() && "Broken AliasAttr handled late!");
5720 S.Diag(Attr->getLocation(), diag::err_alias_is_definition) << VD << 0;
5721 VD->dropAttr<AliasAttr>();
5726 // 'selectany' only applies to externally visible variable declarations.
5727 // It does not apply to functions.
5728 if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) {
5729 if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) {
5730 S.Diag(Attr->getLocation(),
5731 diag::err_attribute_selectany_non_extern_data);
5732 ND.dropAttr<SelectAnyAttr>();
5736 if (const InheritableAttr *Attr = getDLLAttr(&ND)) {
5737 // dll attributes require external linkage. Static locals may have external
5738 // linkage but still cannot be explicitly imported or exported.
5739 auto *VD = dyn_cast<VarDecl>(&ND);
5740 if (!ND.isExternallyVisible() || (VD && VD->isStaticLocal())) {
5741 S.Diag(ND.getLocation(), diag::err_attribute_dll_not_extern)
5743 ND.setInvalidDecl();
5747 // Virtual functions cannot be marked as 'notail'.
5748 if (auto *Attr = ND.getAttr<NotTailCalledAttr>())
5749 if (auto *MD = dyn_cast<CXXMethodDecl>(&ND))
5750 if (MD->isVirtual()) {
5751 S.Diag(ND.getLocation(),
5752 diag::err_invalid_attribute_on_virtual_function)
5754 ND.dropAttr<NotTailCalledAttr>();
5758 static void checkDLLAttributeRedeclaration(Sema &S, NamedDecl *OldDecl,
5760 bool IsSpecialization,
5761 bool IsDefinition) {
5762 if (OldDecl->isInvalidDecl())
5765 bool IsTemplate = false;
5766 if (TemplateDecl *OldTD = dyn_cast<TemplateDecl>(OldDecl)) {
5767 OldDecl = OldTD->getTemplatedDecl();
5769 if (!IsSpecialization)
5770 IsDefinition = false;
5772 if (TemplateDecl *NewTD = dyn_cast<TemplateDecl>(NewDecl)) {
5773 NewDecl = NewTD->getTemplatedDecl();
5777 if (!OldDecl || !NewDecl)
5780 const DLLImportAttr *OldImportAttr = OldDecl->getAttr<DLLImportAttr>();
5781 const DLLExportAttr *OldExportAttr = OldDecl->getAttr<DLLExportAttr>();
5782 const DLLImportAttr *NewImportAttr = NewDecl->getAttr<DLLImportAttr>();
5783 const DLLExportAttr *NewExportAttr = NewDecl->getAttr<DLLExportAttr>();
5785 // dllimport and dllexport are inheritable attributes so we have to exclude
5786 // inherited attribute instances.
5787 bool HasNewAttr = (NewImportAttr && !NewImportAttr->isInherited()) ||
5788 (NewExportAttr && !NewExportAttr->isInherited());
5790 // A redeclaration is not allowed to add a dllimport or dllexport attribute,
5791 // the only exception being explicit specializations.
5792 // Implicitly generated declarations are also excluded for now because there
5793 // is no other way to switch these to use dllimport or dllexport.
5794 bool AddsAttr = !(OldImportAttr || OldExportAttr) && HasNewAttr;
5796 if (AddsAttr && !IsSpecialization && !OldDecl->isImplicit()) {
5797 // Allow with a warning for free functions and global variables.
5798 bool JustWarn = false;
5799 if (!OldDecl->isCXXClassMember()) {
5800 auto *VD = dyn_cast<VarDecl>(OldDecl);
5801 if (VD && !VD->getDescribedVarTemplate())
5803 auto *FD = dyn_cast<FunctionDecl>(OldDecl);
5804 if (FD && FD->getTemplatedKind() == FunctionDecl::TK_NonTemplate)
5808 // We cannot change a declaration that's been used because IR has already
5809 // been emitted. Dllimported functions will still work though (modulo
5810 // address equality) as they can use the thunk.
5811 if (OldDecl->isUsed())
5812 if (!isa<FunctionDecl>(OldDecl) || !NewImportAttr)
5815 unsigned DiagID = JustWarn ? diag::warn_attribute_dll_redeclaration
5816 : diag::err_attribute_dll_redeclaration;
5817 S.Diag(NewDecl->getLocation(), DiagID)
5819 << (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr);
5820 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5822 NewDecl->setInvalidDecl();
5827 // A redeclaration is not allowed to drop a dllimport attribute, the only
5828 // exceptions being inline function definitions (except for function
5829 // templates), local extern declarations, qualified friend declarations or
5830 // special MSVC extension: in the last case, the declaration is treated as if
5831 // it were marked dllexport.
5832 bool IsInline = false, IsStaticDataMember = false, IsQualifiedFriend = false;
5833 bool IsMicrosoft = S.Context.getTargetInfo().getCXXABI().isMicrosoft();
5834 if (const auto *VD = dyn_cast<VarDecl>(NewDecl)) {
5835 // Ignore static data because out-of-line definitions are diagnosed
5837 IsStaticDataMember = VD->isStaticDataMember();
5838 IsDefinition = VD->isThisDeclarationADefinition(S.Context) !=
5839 VarDecl::DeclarationOnly;
5840 } else if (const auto *FD = dyn_cast<FunctionDecl>(NewDecl)) {
5841 IsInline = FD->isInlined();
5842 IsQualifiedFriend = FD->getQualifier() &&
5843 FD->getFriendObjectKind() == Decl::FOK_Declared;
5846 if (OldImportAttr && !HasNewAttr &&
5847 (!IsInline || (IsMicrosoft && IsTemplate)) && !IsStaticDataMember &&
5848 !NewDecl->isLocalExternDecl() && !IsQualifiedFriend) {
5849 if (IsMicrosoft && IsDefinition) {
5850 S.Diag(NewDecl->getLocation(),
5851 diag::warn_redeclaration_without_import_attribute)
5853 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5854 NewDecl->dropAttr<DLLImportAttr>();
5855 NewDecl->addAttr(::new (S.Context) DLLExportAttr(
5856 NewImportAttr->getRange(), S.Context,
5857 NewImportAttr->getSpellingListIndex()));
5859 S.Diag(NewDecl->getLocation(),
5860 diag::warn_redeclaration_without_attribute_prev_attribute_ignored)
5861 << NewDecl << OldImportAttr;
5862 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5863 S.Diag(OldImportAttr->getLocation(), diag::note_previous_attribute);
5864 OldDecl->dropAttr<DLLImportAttr>();
5865 NewDecl->dropAttr<DLLImportAttr>();
5867 } else if (IsInline && OldImportAttr && !IsMicrosoft) {
5868 // In MinGW, seeing a function declared inline drops the dllimport attribute.
5869 OldDecl->dropAttr<DLLImportAttr>();
5870 NewDecl->dropAttr<DLLImportAttr>();
5871 S.Diag(NewDecl->getLocation(),
5872 diag::warn_dllimport_dropped_from_inline_function)
5873 << NewDecl << OldImportAttr;
5877 /// Given that we are within the definition of the given function,
5878 /// will that definition behave like C99's 'inline', where the
5879 /// definition is discarded except for optimization purposes?
5880 static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) {
5881 // Try to avoid calling GetGVALinkageForFunction.
5883 // All cases of this require the 'inline' keyword.
5884 if (!FD->isInlined()) return false;
5886 // This is only possible in C++ with the gnu_inline attribute.
5887 if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>())
5890 // Okay, go ahead and call the relatively-more-expensive function.
5891 return S.Context.GetGVALinkageForFunction(FD) == GVA_AvailableExternally;
5894 /// Determine whether a variable is extern "C" prior to attaching
5895 /// an initializer. We can't just call isExternC() here, because that
5896 /// will also compute and cache whether the declaration is externally
5897 /// visible, which might change when we attach the initializer.
5899 /// This can only be used if the declaration is known to not be a
5900 /// redeclaration of an internal linkage declaration.
5906 /// Attaching the initializer here makes this declaration not externally
5907 /// visible, because its type has internal linkage.
5909 /// FIXME: This is a hack.
5910 template<typename T>
5911 static bool isIncompleteDeclExternC(Sema &S, const T *D) {
5912 if (S.getLangOpts().CPlusPlus) {
5913 // In C++, the overloadable attribute negates the effects of extern "C".
5914 if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>())
5917 // So do CUDA's host/device attributes.
5918 if (S.getLangOpts().CUDA && (D->template hasAttr<CUDADeviceAttr>() ||
5919 D->template hasAttr<CUDAHostAttr>()))
5922 return D->isExternC();
5925 static bool shouldConsiderLinkage(const VarDecl *VD) {
5926 const DeclContext *DC = VD->getDeclContext()->getRedeclContext();
5927 if (DC->isFunctionOrMethod() || isa<OMPDeclareReductionDecl>(DC))
5928 return VD->hasExternalStorage();
5929 if (DC->isFileContext())
5933 llvm_unreachable("Unexpected context");
5936 static bool shouldConsiderLinkage(const FunctionDecl *FD) {
5937 const DeclContext *DC = FD->getDeclContext()->getRedeclContext();
5938 if (DC->isFileContext() || DC->isFunctionOrMethod() ||
5939 isa<OMPDeclareReductionDecl>(DC))
5943 llvm_unreachable("Unexpected context");
5946 static bool hasParsedAttr(Scope *S, const AttributeList *AttrList,
5947 AttributeList::Kind Kind) {
5948 for (const AttributeList *L = AttrList; L; L = L->getNext())
5949 if (L->getKind() == Kind)
5954 static bool hasParsedAttr(Scope *S, const Declarator &PD,
5955 AttributeList::Kind Kind) {
5956 // Check decl attributes on the DeclSpec.
5957 if (hasParsedAttr(S, PD.getDeclSpec().getAttributes().getList(), Kind))
5960 // Walk the declarator structure, checking decl attributes that were in a type
5961 // position to the decl itself.
5962 for (unsigned I = 0, E = PD.getNumTypeObjects(); I != E; ++I) {
5963 if (hasParsedAttr(S, PD.getTypeObject(I).getAttrs(), Kind))
5967 // Finally, check attributes on the decl itself.
5968 return hasParsedAttr(S, PD.getAttributes(), Kind);
5971 /// Adjust the \c DeclContext for a function or variable that might be a
5972 /// function-local external declaration.
5973 bool Sema::adjustContextForLocalExternDecl(DeclContext *&DC) {
5974 if (!DC->isFunctionOrMethod())
5977 // If this is a local extern function or variable declared within a function
5978 // template, don't add it into the enclosing namespace scope until it is
5979 // instantiated; it might have a dependent type right now.
5980 if (DC->isDependentContext())
5983 // C++11 [basic.link]p7:
5984 // When a block scope declaration of an entity with linkage is not found to
5985 // refer to some other declaration, then that entity is a member of the
5986 // innermost enclosing namespace.
5988 // Per C++11 [namespace.def]p6, the innermost enclosing namespace is a
5989 // semantically-enclosing namespace, not a lexically-enclosing one.
5990 while (!DC->isFileContext() && !isa<LinkageSpecDecl>(DC))
5991 DC = DC->getParent();
5995 /// \brief Returns true if given declaration has external C language linkage.
5996 static bool isDeclExternC(const Decl *D) {
5997 if (const auto *FD = dyn_cast<FunctionDecl>(D))
5998 return FD->isExternC();
5999 if (const auto *VD = dyn_cast<VarDecl>(D))
6000 return VD->isExternC();
6002 llvm_unreachable("Unknown type of decl!");
6005 NamedDecl *Sema::ActOnVariableDeclarator(
6006 Scope *S, Declarator &D, DeclContext *DC, TypeSourceInfo *TInfo,
6007 LookupResult &Previous, MultiTemplateParamsArg TemplateParamLists,
6008 bool &AddToScope, ArrayRef<BindingDecl *> Bindings) {
6009 QualType R = TInfo->getType();
6010 DeclarationName Name = GetNameForDeclarator(D).getName();
6012 IdentifierInfo *II = Name.getAsIdentifierInfo();
6014 if (D.isDecompositionDeclarator()) {
6016 // Take the name of the first declarator as our name for diagnostic
6018 auto &Decomp = D.getDecompositionDeclarator();
6019 if (!Decomp.bindings().empty()) {
6020 II = Decomp.bindings()[0].Name;
6024 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) << Name;
6028 if (getLangOpts().OpenCL) {
6029 // OpenCL v2.0 s6.9.b - Image type can only be used as a function argument.
6030 // OpenCL v2.0 s6.13.16.1 - Pipe type can only be used as a function
6032 if (R->isImageType() || R->isPipeType()) {
6033 Diag(D.getIdentifierLoc(),
6034 diag::err_opencl_type_can_only_be_used_as_function_parameter)
6040 // OpenCL v1.2 s6.9.r:
6041 // The event type cannot be used to declare a program scope variable.
6042 // OpenCL v2.0 s6.9.q:
6043 // The clk_event_t and reserve_id_t types cannot be declared in program scope.
6044 if (NULL == S->getParent()) {
6045 if (R->isReserveIDT() || R->isClkEventT() || R->isEventT()) {
6046 Diag(D.getIdentifierLoc(),
6047 diag::err_invalid_type_for_program_scope_var) << R;
6053 // OpenCL v1.0 s6.8.a.3: Pointers to functions are not allowed.
6055 while (NR->isPointerType()) {
6056 if (NR->isFunctionPointerType()) {
6057 Diag(D.getIdentifierLoc(), diag::err_opencl_function_pointer_variable);
6061 NR = NR->getPointeeType();
6064 if (!getOpenCLOptions().isEnabled("cl_khr_fp16")) {
6065 // OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and
6066 // half array type (unless the cl_khr_fp16 extension is enabled).
6067 if (Context.getBaseElementType(R)->isHalfType()) {
6068 Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R;
6073 // OpenCL v1.2 s6.9.b p4:
6074 // The sampler type cannot be used with the __local and __global address
6075 // space qualifiers.
6076 if (R->isSamplerT() && (R.getAddressSpace() == LangAS::opencl_local ||
6077 R.getAddressSpace() == LangAS::opencl_global)) {
6078 Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace);
6081 // OpenCL v1.2 s6.9.r:
6082 // The event type cannot be used with the __local, __constant and __global
6083 // address space qualifiers.
6084 if (R->isEventT()) {
6085 if (R.getAddressSpace()) {
6086 Diag(D.getLocStart(), diag::err_event_t_addr_space_qual);
6092 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec();
6093 StorageClass SC = StorageClassSpecToVarDeclStorageClass(D.getDeclSpec());
6095 // dllimport globals without explicit storage class are treated as extern. We
6096 // have to change the storage class this early to get the right DeclContext.
6097 if (SC == SC_None && !DC->isRecord() &&
6098 hasParsedAttr(S, D, AttributeList::AT_DLLImport) &&
6099 !hasParsedAttr(S, D, AttributeList::AT_DLLExport))
6102 DeclContext *OriginalDC = DC;
6103 bool IsLocalExternDecl = SC == SC_Extern &&
6104 adjustContextForLocalExternDecl(DC);
6106 if (SCSpec == DeclSpec::SCS_mutable) {
6107 // mutable can only appear on non-static class members, so it's always
6109 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember);
6114 if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register &&
6115 !D.getAsmLabel() && !getSourceManager().isInSystemMacro(
6116 D.getDeclSpec().getStorageClassSpecLoc())) {
6117 // In C++11, the 'register' storage class specifier is deprecated.
6118 // Suppress the warning in system macros, it's used in macros in some
6119 // popular C system headers, such as in glibc's htonl() macro.
6120 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6121 getLangOpts().CPlusPlus1z ? diag::ext_register_storage_class
6122 : diag::warn_deprecated_register)
6123 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6126 DiagnoseFunctionSpecifiers(D.getDeclSpec());
6128 if (!DC->isRecord() && S->getFnParent() == nullptr) {
6129 // C99 6.9p2: The storage-class specifiers auto and register shall not
6130 // appear in the declaration specifiers in an external declaration.
6131 // Global Register+Asm is a GNU extension we support.
6132 if (SC == SC_Auto || (SC == SC_Register && !D.getAsmLabel())) {
6133 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope);
6138 bool IsMemberSpecialization = false;
6139 bool IsVariableTemplateSpecialization = false;
6140 bool IsPartialSpecialization = false;
6141 bool IsVariableTemplate = false;
6142 VarDecl *NewVD = nullptr;
6143 VarTemplateDecl *NewTemplate = nullptr;
6144 TemplateParameterList *TemplateParams = nullptr;
6145 if (!getLangOpts().CPlusPlus) {
6146 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
6147 D.getIdentifierLoc(), II,
6150 if (R->getContainedDeducedType())
6151 ParsingInitForAutoVars.insert(NewVD);
6153 if (D.isInvalidType())
6154 NewVD->setInvalidDecl();
6156 bool Invalid = false;
6158 if (DC->isRecord() && !CurContext->isRecord()) {
6159 // This is an out-of-line definition of a static data member.
6164 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6165 diag::err_static_out_of_line)
6166 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6171 // [dcl.stc] p2: The auto or register specifiers shall be applied only
6172 // to names of variables declared in a block or to function parameters.
6173 // [dcl.stc] p6: The extern specifier cannot be used in the declaration
6176 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6177 diag::err_storage_class_for_static_member)
6178 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6180 case SC_PrivateExtern:
6181 llvm_unreachable("C storage class in c++!");
6185 if (SC == SC_Static && CurContext->isRecord()) {
6186 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) {
6187 if (RD->isLocalClass())
6188 Diag(D.getIdentifierLoc(),
6189 diag::err_static_data_member_not_allowed_in_local_class)
6190 << Name << RD->getDeclName();
6192 // C++98 [class.union]p1: If a union contains a static data member,
6193 // the program is ill-formed. C++11 drops this restriction.
6195 Diag(D.getIdentifierLoc(),
6196 getLangOpts().CPlusPlus11
6197 ? diag::warn_cxx98_compat_static_data_member_in_union
6198 : diag::ext_static_data_member_in_union) << Name;
6199 // We conservatively disallow static data members in anonymous structs.
6200 else if (!RD->getDeclName())
6201 Diag(D.getIdentifierLoc(),
6202 diag::err_static_data_member_not_allowed_in_anon_struct)
6203 << Name << RD->isUnion();
6207 // Match up the template parameter lists with the scope specifier, then
6208 // determine whether we have a template or a template specialization.
6209 TemplateParams = MatchTemplateParametersToScopeSpecifier(
6210 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
6211 D.getCXXScopeSpec(),
6212 D.getName().getKind() == UnqualifiedId::IK_TemplateId
6213 ? D.getName().TemplateId
6216 /*never a friend*/ false, IsMemberSpecialization, Invalid);
6218 if (TemplateParams) {
6219 if (!TemplateParams->size() &&
6220 D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
6221 // There is an extraneous 'template<>' for this variable. Complain
6222 // about it, but allow the declaration of the variable.
6223 Diag(TemplateParams->getTemplateLoc(),
6224 diag::err_template_variable_noparams)
6226 << SourceRange(TemplateParams->getTemplateLoc(),
6227 TemplateParams->getRAngleLoc());
6228 TemplateParams = nullptr;
6230 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
6231 // This is an explicit specialization or a partial specialization.
6232 // FIXME: Check that we can declare a specialization here.
6233 IsVariableTemplateSpecialization = true;
6234 IsPartialSpecialization = TemplateParams->size() > 0;
6235 } else { // if (TemplateParams->size() > 0)
6236 // This is a template declaration.
6237 IsVariableTemplate = true;
6239 // Check that we can declare a template here.
6240 if (CheckTemplateDeclScope(S, TemplateParams))
6243 // Only C++1y supports variable templates (N3651).
6244 Diag(D.getIdentifierLoc(),
6245 getLangOpts().CPlusPlus14
6246 ? diag::warn_cxx11_compat_variable_template
6247 : diag::ext_variable_template);
6252 (Invalid || D.getName().getKind() != UnqualifiedId::IK_TemplateId) &&
6253 "should have a 'template<>' for this decl");
6256 if (IsVariableTemplateSpecialization) {
6257 SourceLocation TemplateKWLoc =
6258 TemplateParamLists.size() > 0
6259 ? TemplateParamLists[0]->getTemplateLoc()
6261 DeclResult Res = ActOnVarTemplateSpecialization(
6262 S, D, TInfo, TemplateKWLoc, TemplateParams, SC,
6263 IsPartialSpecialization);
6264 if (Res.isInvalid())
6266 NewVD = cast<VarDecl>(Res.get());
6268 } else if (D.isDecompositionDeclarator()) {
6269 NewVD = DecompositionDecl::Create(Context, DC, D.getLocStart(),
6270 D.getIdentifierLoc(), R, TInfo, SC,
6273 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
6274 D.getIdentifierLoc(), II, R, TInfo, SC);
6276 // If this is supposed to be a variable template, create it as such.
6277 if (IsVariableTemplate) {
6279 VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name,
6280 TemplateParams, NewVD);
6281 NewVD->setDescribedVarTemplate(NewTemplate);
6284 // If this decl has an auto type in need of deduction, make a note of the
6285 // Decl so we can diagnose uses of it in its own initializer.
6286 if (R->getContainedDeducedType())
6287 ParsingInitForAutoVars.insert(NewVD);
6289 if (D.isInvalidType() || Invalid) {
6290 NewVD->setInvalidDecl();
6292 NewTemplate->setInvalidDecl();
6295 SetNestedNameSpecifier(NewVD, D);
6297 // If we have any template parameter lists that don't directly belong to
6298 // the variable (matching the scope specifier), store them.
6299 unsigned VDTemplateParamLists = TemplateParams ? 1 : 0;
6300 if (TemplateParamLists.size() > VDTemplateParamLists)
6301 NewVD->setTemplateParameterListsInfo(
6302 Context, TemplateParamLists.drop_back(VDTemplateParamLists));
6304 if (D.getDeclSpec().isConstexprSpecified()) {
6305 NewVD->setConstexpr(true);
6306 // C++1z [dcl.spec.constexpr]p1:
6307 // A static data member declared with the constexpr specifier is
6308 // implicitly an inline variable.
6309 if (NewVD->isStaticDataMember() && getLangOpts().CPlusPlus1z)
6310 NewVD->setImplicitlyInline();
6313 if (D.getDeclSpec().isConceptSpecified()) {
6314 if (VarTemplateDecl *VTD = NewVD->getDescribedVarTemplate())
6317 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
6318 // be declared with the thread_local, inline, friend, or constexpr
6319 // specifiers, [...]
6320 if (D.getDeclSpec().getThreadStorageClassSpec() == TSCS_thread_local) {
6321 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6322 diag::err_concept_decl_invalid_specifiers)
6324 NewVD->setInvalidDecl(true);
6327 if (D.getDeclSpec().isConstexprSpecified()) {
6328 Diag(D.getDeclSpec().getConstexprSpecLoc(),
6329 diag::err_concept_decl_invalid_specifiers)
6331 NewVD->setInvalidDecl(true);
6334 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
6335 // applied only to the definition of a function template or variable
6336 // template, declared in namespace scope.
6337 if (IsVariableTemplateSpecialization) {
6338 Diag(D.getDeclSpec().getConceptSpecLoc(),
6339 diag::err_concept_specified_specialization)
6340 << (IsPartialSpecialization ? 2 : 1);
6343 // C++ Concepts TS [dcl.spec.concept]p6: A variable concept has the
6344 // following restrictions:
6345 // - The declared type shall have the type bool.
6346 if (!Context.hasSameType(NewVD->getType(), Context.BoolTy) &&
6347 !NewVD->isInvalidDecl()) {
6348 Diag(D.getIdentifierLoc(), diag::err_variable_concept_bool_decl);
6349 NewVD->setInvalidDecl(true);
6354 if (D.getDeclSpec().isInlineSpecified()) {
6355 if (!getLangOpts().CPlusPlus) {
6356 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
6358 } else if (CurContext->isFunctionOrMethod()) {
6359 // 'inline' is not allowed on block scope variable declaration.
6360 Diag(D.getDeclSpec().getInlineSpecLoc(),
6361 diag::err_inline_declaration_block_scope) << Name
6362 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
6364 Diag(D.getDeclSpec().getInlineSpecLoc(),
6365 getLangOpts().CPlusPlus1z ? diag::warn_cxx14_compat_inline_variable
6366 : diag::ext_inline_variable);
6367 NewVD->setInlineSpecified();
6371 // Set the lexical context. If the declarator has a C++ scope specifier, the
6372 // lexical context will be different from the semantic context.
6373 NewVD->setLexicalDeclContext(CurContext);
6375 NewTemplate->setLexicalDeclContext(CurContext);
6377 if (IsLocalExternDecl) {
6378 if (D.isDecompositionDeclarator())
6379 for (auto *B : Bindings)
6380 B->setLocalExternDecl();
6382 NewVD->setLocalExternDecl();
6385 bool EmitTLSUnsupportedError = false;
6386 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) {
6387 // C++11 [dcl.stc]p4:
6388 // When thread_local is applied to a variable of block scope the
6389 // storage-class-specifier static is implied if it does not appear
6391 // Core issue: 'static' is not implied if the variable is declared
6393 if (NewVD->hasLocalStorage() &&
6394 (SCSpec != DeclSpec::SCS_unspecified ||
6395 TSCS != DeclSpec::TSCS_thread_local ||
6396 !DC->isFunctionOrMethod()))
6397 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6398 diag::err_thread_non_global)
6399 << DeclSpec::getSpecifierName(TSCS);
6400 else if (!Context.getTargetInfo().isTLSSupported()) {
6401 if (getLangOpts().CUDA) {
6402 // Postpone error emission until we've collected attributes required to
6403 // figure out whether it's a host or device variable and whether the
6404 // error should be ignored.
6405 EmitTLSUnsupportedError = true;
6406 // We still need to mark the variable as TLS so it shows up in AST with
6407 // proper storage class for other tools to use even if we're not going
6408 // to emit any code for it.
6409 NewVD->setTSCSpec(TSCS);
6411 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6412 diag::err_thread_unsupported);
6414 NewVD->setTSCSpec(TSCS);
6418 // An inline definition of a function with external linkage shall
6419 // not contain a definition of a modifiable object with static or
6420 // thread storage duration...
6421 // We only apply this when the function is required to be defined
6422 // elsewhere, i.e. when the function is not 'extern inline'. Note
6423 // that a local variable with thread storage duration still has to
6424 // be marked 'static'. Also note that it's possible to get these
6425 // semantics in C++ using __attribute__((gnu_inline)).
6426 if (SC == SC_Static && S->getFnParent() != nullptr &&
6427 !NewVD->getType().isConstQualified()) {
6428 FunctionDecl *CurFD = getCurFunctionDecl();
6429 if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) {
6430 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6431 diag::warn_static_local_in_extern_inline);
6432 MaybeSuggestAddingStaticToDecl(CurFD);
6436 if (D.getDeclSpec().isModulePrivateSpecified()) {
6437 if (IsVariableTemplateSpecialization)
6438 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6439 << (IsPartialSpecialization ? 1 : 0)
6440 << FixItHint::CreateRemoval(
6441 D.getDeclSpec().getModulePrivateSpecLoc());
6442 else if (IsMemberSpecialization)
6443 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6445 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6446 else if (NewVD->hasLocalStorage())
6447 Diag(NewVD->getLocation(), diag::err_module_private_local)
6448 << 0 << NewVD->getDeclName()
6449 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
6450 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6452 NewVD->setModulePrivate();
6454 NewTemplate->setModulePrivate();
6455 for (auto *B : Bindings)
6456 B->setModulePrivate();
6460 // Handle attributes prior to checking for duplicates in MergeVarDecl
6461 ProcessDeclAttributes(S, NewVD, D);
6463 if (getLangOpts().CUDA) {
6464 if (EmitTLSUnsupportedError && DeclAttrsMatchCUDAMode(getLangOpts(), NewVD))
6465 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6466 diag::err_thread_unsupported);
6467 // CUDA B.2.5: "__shared__ and __constant__ variables have implied static
6468 // storage [duration]."
6469 if (SC == SC_None && S->getFnParent() != nullptr &&
6470 (NewVD->hasAttr<CUDASharedAttr>() ||
6471 NewVD->hasAttr<CUDAConstantAttr>())) {
6472 NewVD->setStorageClass(SC_Static);
6476 // Ensure that dllimport globals without explicit storage class are treated as
6477 // extern. The storage class is set above using parsed attributes. Now we can
6478 // check the VarDecl itself.
6479 assert(!NewVD->hasAttr<DLLImportAttr>() ||
6480 NewVD->getAttr<DLLImportAttr>()->isInherited() ||
6481 NewVD->isStaticDataMember() || NewVD->getStorageClass() != SC_None);
6483 // In auto-retain/release, infer strong retension for variables of
6485 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD))
6486 NewVD->setInvalidDecl();
6488 // Handle GNU asm-label extension (encoded as an attribute).
6489 if (Expr *E = (Expr*)D.getAsmLabel()) {
6490 // The parser guarantees this is a string.
6491 StringLiteral *SE = cast<StringLiteral>(E);
6492 StringRef Label = SE->getString();
6493 if (S->getFnParent() != nullptr) {
6497 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label;
6500 // Local Named register
6501 if (!Context.getTargetInfo().isValidGCCRegisterName(Label) &&
6502 DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl()))
6503 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6507 case SC_PrivateExtern:
6510 } else if (SC == SC_Register) {
6511 // Global Named register
6512 if (DeclAttrsMatchCUDAMode(getLangOpts(), NewVD)) {
6513 const auto &TI = Context.getTargetInfo();
6514 bool HasSizeMismatch;
6516 if (!TI.isValidGCCRegisterName(Label))
6517 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6518 else if (!TI.validateGlobalRegisterVariable(Label,
6519 Context.getTypeSize(R),
6521 Diag(E->getExprLoc(), diag::err_asm_invalid_global_var_reg) << Label;
6522 else if (HasSizeMismatch)
6523 Diag(E->getExprLoc(), diag::err_asm_register_size_mismatch) << Label;
6526 if (!R->isIntegralType(Context) && !R->isPointerType()) {
6527 Diag(D.getLocStart(), diag::err_asm_bad_register_type);
6528 NewVD->setInvalidDecl(true);
6532 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0),
6533 Context, Label, 0));
6534 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
6535 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
6536 ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier());
6537 if (I != ExtnameUndeclaredIdentifiers.end()) {
6538 if (isDeclExternC(NewVD)) {
6539 NewVD->addAttr(I->second);
6540 ExtnameUndeclaredIdentifiers.erase(I);
6542 Diag(NewVD->getLocation(), diag::warn_redefine_extname_not_applied)
6543 << /*Variable*/1 << NewVD;
6547 // Find the shadowed declaration before filtering for scope.
6548 NamedDecl *ShadowedDecl = D.getCXXScopeSpec().isEmpty()
6549 ? getShadowedDeclaration(NewVD, Previous)
6552 // Don't consider existing declarations that are in a different
6553 // scope and are out-of-semantic-context declarations (if the new
6554 // declaration has linkage).
6555 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewVD),
6556 D.getCXXScopeSpec().isNotEmpty() ||
6557 IsMemberSpecialization ||
6558 IsVariableTemplateSpecialization);
6560 // Check whether the previous declaration is in the same block scope. This
6561 // affects whether we merge types with it, per C++11 [dcl.array]p3.
6562 if (getLangOpts().CPlusPlus &&
6563 NewVD->isLocalVarDecl() && NewVD->hasExternalStorage())
6564 NewVD->setPreviousDeclInSameBlockScope(
6565 Previous.isSingleResult() && !Previous.isShadowed() &&
6566 isDeclInScope(Previous.getFoundDecl(), OriginalDC, S, false));
6568 if (!getLangOpts().CPlusPlus) {
6569 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6571 // If this is an explicit specialization of a static data member, check it.
6572 if (IsMemberSpecialization && !NewVD->isInvalidDecl() &&
6573 CheckMemberSpecialization(NewVD, Previous))
6574 NewVD->setInvalidDecl();
6576 // Merge the decl with the existing one if appropriate.
6577 if (!Previous.empty()) {
6578 if (Previous.isSingleResult() &&
6579 isa<FieldDecl>(Previous.getFoundDecl()) &&
6580 D.getCXXScopeSpec().isSet()) {
6581 // The user tried to define a non-static data member
6582 // out-of-line (C++ [dcl.meaning]p1).
6583 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line)
6584 << D.getCXXScopeSpec().getRange();
6586 NewVD->setInvalidDecl();
6588 } else if (D.getCXXScopeSpec().isSet()) {
6589 // No previous declaration in the qualifying scope.
6590 Diag(D.getIdentifierLoc(), diag::err_no_member)
6591 << Name << computeDeclContext(D.getCXXScopeSpec(), true)
6592 << D.getCXXScopeSpec().getRange();
6593 NewVD->setInvalidDecl();
6596 if (!IsVariableTemplateSpecialization)
6597 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6599 // C++ Concepts TS [dcl.spec.concept]p7: A program shall not declare [...]
6600 // an explicit specialization (14.8.3) or a partial specialization of a
6601 // concept definition.
6602 if (IsVariableTemplateSpecialization &&
6603 !D.getDeclSpec().isConceptSpecified() && !Previous.empty() &&
6604 Previous.isSingleResult()) {
6605 NamedDecl *PreviousDecl = Previous.getFoundDecl();
6606 if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(PreviousDecl)) {
6607 if (VarTmpl->isConcept()) {
6608 Diag(NewVD->getLocation(), diag::err_concept_specialized)
6610 << (IsPartialSpecialization ? 2 /*partially specialized*/
6611 : 1 /*explicitly specialized*/);
6612 Diag(VarTmpl->getLocation(), diag::note_previous_declaration);
6613 NewVD->setInvalidDecl();
6619 VarTemplateDecl *PrevVarTemplate =
6620 NewVD->getPreviousDecl()
6621 ? NewVD->getPreviousDecl()->getDescribedVarTemplate()
6624 // Check the template parameter list of this declaration, possibly
6625 // merging in the template parameter list from the previous variable
6626 // template declaration.
6627 if (CheckTemplateParameterList(
6629 PrevVarTemplate ? PrevVarTemplate->getTemplateParameters()
6631 (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() &&
6632 DC->isDependentContext())
6633 ? TPC_ClassTemplateMember
6635 NewVD->setInvalidDecl();
6637 // If we are providing an explicit specialization of a static variable
6638 // template, make a note of that.
6639 if (PrevVarTemplate &&
6640 PrevVarTemplate->getInstantiatedFromMemberTemplate())
6641 PrevVarTemplate->setMemberSpecialization();
6645 // Diagnose shadowed variables iff this isn't a redeclaration.
6646 if (ShadowedDecl && !D.isRedeclaration())
6647 CheckShadow(NewVD, ShadowedDecl, Previous);
6649 ProcessPragmaWeak(S, NewVD);
6651 // If this is the first declaration of an extern C variable, update
6652 // the map of such variables.
6653 if (NewVD->isFirstDecl() && !NewVD->isInvalidDecl() &&
6654 isIncompleteDeclExternC(*this, NewVD))
6655 RegisterLocallyScopedExternCDecl(NewVD, S);
6657 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
6658 Decl *ManglingContextDecl;
6659 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
6660 NewVD->getDeclContext(), ManglingContextDecl)) {
6661 Context.setManglingNumber(
6662 NewVD, MCtx->getManglingNumber(
6663 NewVD, getMSManglingNumber(getLangOpts(), S)));
6664 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
6668 // Special handling of variable named 'main'.
6669 if (Name.getAsIdentifierInfo() && Name.getAsIdentifierInfo()->isStr("main") &&
6670 NewVD->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
6671 !getLangOpts().Freestanding && !NewVD->getDescribedVarTemplate()) {
6673 // C++ [basic.start.main]p3
6674 // A program that declares a variable main at global scope is ill-formed.
6675 if (getLangOpts().CPlusPlus)
6676 Diag(D.getLocStart(), diag::err_main_global_variable);
6678 // In C, and external-linkage variable named main results in undefined
6680 else if (NewVD->hasExternalFormalLinkage())
6681 Diag(D.getLocStart(), diag::warn_main_redefined);
6684 if (D.isRedeclaration() && !Previous.empty()) {
6685 checkDLLAttributeRedeclaration(
6686 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewVD,
6687 IsMemberSpecialization, D.isFunctionDefinition());
6691 if (NewVD->isInvalidDecl())
6692 NewTemplate->setInvalidDecl();
6693 ActOnDocumentableDecl(NewTemplate);
6700 /// Enum describing the %select options in diag::warn_decl_shadow.
6701 enum ShadowedDeclKind {
6710 /// Determine what kind of declaration we're shadowing.
6711 static ShadowedDeclKind computeShadowedDeclKind(const NamedDecl *ShadowedDecl,
6712 const DeclContext *OldDC) {
6713 if (isa<TypeAliasDecl>(ShadowedDecl))
6715 else if (isa<TypedefDecl>(ShadowedDecl))
6717 else if (isa<RecordDecl>(OldDC))
6718 return isa<FieldDecl>(ShadowedDecl) ? SDK_Field : SDK_StaticMember;
6720 return OldDC->isFileContext() ? SDK_Global : SDK_Local;
6723 /// Return the location of the capture if the given lambda captures the given
6724 /// variable \p VD, or an invalid source location otherwise.
6725 static SourceLocation getCaptureLocation(const LambdaScopeInfo *LSI,
6726 const VarDecl *VD) {
6727 for (const LambdaScopeInfo::Capture &Capture : LSI->Captures) {
6728 if (Capture.isVariableCapture() && Capture.getVariable() == VD)
6729 return Capture.getLocation();
6731 return SourceLocation();
6734 static bool shouldWarnIfShadowedDecl(const DiagnosticsEngine &Diags,
6735 const LookupResult &R) {
6736 // Only diagnose if we're shadowing an unambiguous field or variable.
6737 if (R.getResultKind() != LookupResult::Found)
6740 // Return false if warning is ignored.
6741 return !Diags.isIgnored(diag::warn_decl_shadow, R.getNameLoc());
6744 /// \brief Return the declaration shadowed by the given variable \p D, or null
6745 /// if it doesn't shadow any declaration or shadowing warnings are disabled.
6746 NamedDecl *Sema::getShadowedDeclaration(const VarDecl *D,
6747 const LookupResult &R) {
6748 if (!shouldWarnIfShadowedDecl(Diags, R))
6751 // Don't diagnose declarations at file scope.
6752 if (D->hasGlobalStorage())
6755 NamedDecl *ShadowedDecl = R.getFoundDecl();
6756 return isa<VarDecl>(ShadowedDecl) || isa<FieldDecl>(ShadowedDecl)
6761 /// \brief Return the declaration shadowed by the given typedef \p D, or null
6762 /// if it doesn't shadow any declaration or shadowing warnings are disabled.
6763 NamedDecl *Sema::getShadowedDeclaration(const TypedefNameDecl *D,
6764 const LookupResult &R) {
6765 // Don't warn if typedef declaration is part of a class
6766 if (D->getDeclContext()->isRecord())
6769 if (!shouldWarnIfShadowedDecl(Diags, R))
6772 NamedDecl *ShadowedDecl = R.getFoundDecl();
6773 return isa<TypedefNameDecl>(ShadowedDecl) ? ShadowedDecl : nullptr;
6776 /// \brief Diagnose variable or built-in function shadowing. Implements
6779 /// This method is called whenever a VarDecl is added to a "useful"
6782 /// \param ShadowedDecl the declaration that is shadowed by the given variable
6783 /// \param R the lookup of the name
6785 void Sema::CheckShadow(NamedDecl *D, NamedDecl *ShadowedDecl,
6786 const LookupResult &R) {
6787 DeclContext *NewDC = D->getDeclContext();
6789 if (FieldDecl *FD = dyn_cast<FieldDecl>(ShadowedDecl)) {
6790 // Fields are not shadowed by variables in C++ static methods.
6791 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC))
6795 // Fields shadowed by constructor parameters are a special case. Usually
6796 // the constructor initializes the field with the parameter.
6797 if (isa<CXXConstructorDecl>(NewDC))
6798 if (const auto PVD = dyn_cast<ParmVarDecl>(D)) {
6799 // Remember that this was shadowed so we can either warn about its
6800 // modification or its existence depending on warning settings.
6801 ShadowingDecls.insert({PVD->getCanonicalDecl(), FD});
6806 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl))
6807 if (shadowedVar->isExternC()) {
6808 // For shadowing external vars, make sure that we point to the global
6809 // declaration, not a locally scoped extern declaration.
6810 for (auto I : shadowedVar->redecls())
6811 if (I->isFileVarDecl()) {
6817 DeclContext *OldDC = ShadowedDecl->getDeclContext();
6819 unsigned WarningDiag = diag::warn_decl_shadow;
6820 SourceLocation CaptureLoc;
6821 if (isa<VarDecl>(D) && isa<VarDecl>(ShadowedDecl) && NewDC &&
6822 isa<CXXMethodDecl>(NewDC)) {
6823 if (const auto *RD = dyn_cast<CXXRecordDecl>(NewDC->getParent())) {
6824 if (RD->isLambda() && OldDC->Encloses(NewDC->getLexicalParent())) {
6825 if (RD->getLambdaCaptureDefault() == LCD_None) {
6826 // Try to avoid warnings for lambdas with an explicit capture list.
6827 const auto *LSI = cast<LambdaScopeInfo>(getCurFunction());
6828 // Warn only when the lambda captures the shadowed decl explicitly.
6829 CaptureLoc = getCaptureLocation(LSI, cast<VarDecl>(ShadowedDecl));
6830 if (CaptureLoc.isInvalid())
6831 WarningDiag = diag::warn_decl_shadow_uncaptured_local;
6833 // Remember that this was shadowed so we can avoid the warning if the
6834 // shadowed decl isn't captured and the warning settings allow it.
6835 cast<LambdaScopeInfo>(getCurFunction())
6836 ->ShadowingDecls.push_back(
6837 {cast<VarDecl>(D), cast<VarDecl>(ShadowedDecl)});
6844 // Only warn about certain kinds of shadowing for class members.
6845 if (NewDC && NewDC->isRecord()) {
6846 // In particular, don't warn about shadowing non-class members.
6847 if (!OldDC->isRecord())
6850 // TODO: should we warn about static data members shadowing
6851 // static data members from base classes?
6853 // TODO: don't diagnose for inaccessible shadowed members.
6854 // This is hard to do perfectly because we might friend the
6855 // shadowing context, but that's just a false negative.
6859 DeclarationName Name = R.getLookupName();
6861 // Emit warning and note.
6862 if (getSourceManager().isInSystemMacro(R.getNameLoc()))
6864 ShadowedDeclKind Kind = computeShadowedDeclKind(ShadowedDecl, OldDC);
6865 Diag(R.getNameLoc(), WarningDiag) << Name << Kind << OldDC;
6866 if (!CaptureLoc.isInvalid())
6867 Diag(CaptureLoc, diag::note_var_explicitly_captured_here)
6868 << Name << /*explicitly*/ 1;
6869 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6872 /// Diagnose shadowing for variables shadowed in the lambda record \p LambdaRD
6873 /// when these variables are captured by the lambda.
6874 void Sema::DiagnoseShadowingLambdaDecls(const LambdaScopeInfo *LSI) {
6875 for (const auto &Shadow : LSI->ShadowingDecls) {
6876 const VarDecl *ShadowedDecl = Shadow.ShadowedDecl;
6877 // Try to avoid the warning when the shadowed decl isn't captured.
6878 SourceLocation CaptureLoc = getCaptureLocation(LSI, ShadowedDecl);
6879 const DeclContext *OldDC = ShadowedDecl->getDeclContext();
6880 Diag(Shadow.VD->getLocation(), CaptureLoc.isInvalid()
6881 ? diag::warn_decl_shadow_uncaptured_local
6882 : diag::warn_decl_shadow)
6883 << Shadow.VD->getDeclName()
6884 << computeShadowedDeclKind(ShadowedDecl, OldDC) << OldDC;
6885 if (!CaptureLoc.isInvalid())
6886 Diag(CaptureLoc, diag::note_var_explicitly_captured_here)
6887 << Shadow.VD->getDeclName() << /*explicitly*/ 0;
6888 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6892 /// \brief Check -Wshadow without the advantage of a previous lookup.
6893 void Sema::CheckShadow(Scope *S, VarDecl *D) {
6894 if (Diags.isIgnored(diag::warn_decl_shadow, D->getLocation()))
6897 LookupResult R(*this, D->getDeclName(), D->getLocation(),
6898 Sema::LookupOrdinaryName, Sema::ForRedeclaration);
6900 if (NamedDecl *ShadowedDecl = getShadowedDeclaration(D, R))
6901 CheckShadow(D, ShadowedDecl, R);
6904 /// Check if 'E', which is an expression that is about to be modified, refers
6905 /// to a constructor parameter that shadows a field.
6906 void Sema::CheckShadowingDeclModification(Expr *E, SourceLocation Loc) {
6907 // Quickly ignore expressions that can't be shadowing ctor parameters.
6908 if (!getLangOpts().CPlusPlus || ShadowingDecls.empty())
6910 E = E->IgnoreParenImpCasts();
6911 auto *DRE = dyn_cast<DeclRefExpr>(E);
6914 const NamedDecl *D = cast<NamedDecl>(DRE->getDecl()->getCanonicalDecl());
6915 auto I = ShadowingDecls.find(D);
6916 if (I == ShadowingDecls.end())
6918 const NamedDecl *ShadowedDecl = I->second;
6919 const DeclContext *OldDC = ShadowedDecl->getDeclContext();
6920 Diag(Loc, diag::warn_modifying_shadowing_decl) << D << OldDC;
6921 Diag(D->getLocation(), diag::note_var_declared_here) << D;
6922 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6924 // Avoid issuing multiple warnings about the same decl.
6925 ShadowingDecls.erase(I);
6928 /// Check for conflict between this global or extern "C" declaration and
6929 /// previous global or extern "C" declarations. This is only used in C++.
6930 template<typename T>
6931 static bool checkGlobalOrExternCConflict(
6932 Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) {
6933 assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\"");
6934 NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName());
6936 if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) {
6937 // The common case: this global doesn't conflict with any extern "C"
6943 if (!IsGlobal || isIncompleteDeclExternC(S, ND)) {
6944 // Both the old and new declarations have C language linkage. This is a
6947 Previous.addDecl(Prev);
6951 // This is a global, non-extern "C" declaration, and there is a previous
6952 // non-global extern "C" declaration. Diagnose if this is a variable
6954 if (!isa<VarDecl>(ND))
6957 // The declaration is extern "C". Check for any declaration in the
6958 // translation unit which might conflict.
6960 // We have already performed the lookup into the translation unit.
6962 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6964 if (isa<VarDecl>(*I)) {
6970 DeclContext::lookup_result R =
6971 S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName());
6972 for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end();
6974 if (isa<VarDecl>(*I)) {
6978 // FIXME: If we have any other entity with this name in global scope,
6979 // the declaration is ill-formed, but that is a defect: it breaks the
6980 // 'stat' hack, for instance. Only variables can have mangled name
6981 // clashes with extern "C" declarations, so only they deserve a
6990 // Use the first declaration's location to ensure we point at something which
6991 // is lexically inside an extern "C" linkage-spec.
6992 assert(Prev && "should have found a previous declaration to diagnose");
6993 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev))
6994 Prev = FD->getFirstDecl();
6996 Prev = cast<VarDecl>(Prev)->getFirstDecl();
6998 S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict)
7000 S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict)
7005 /// Apply special rules for handling extern "C" declarations. Returns \c true
7006 /// if we have found that this is a redeclaration of some prior entity.
7008 /// Per C++ [dcl.link]p6:
7009 /// Two declarations [for a function or variable] with C language linkage
7010 /// with the same name that appear in different scopes refer to the same
7011 /// [entity]. An entity with C language linkage shall not be declared with
7012 /// the same name as an entity in global scope.
7013 template<typename T>
7014 static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND,
7015 LookupResult &Previous) {
7016 if (!S.getLangOpts().CPlusPlus) {
7017 // In C, when declaring a global variable, look for a corresponding 'extern'
7018 // variable declared in function scope. We don't need this in C++, because
7019 // we find local extern decls in the surrounding file-scope DeclContext.
7020 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
7021 if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) {
7023 Previous.addDecl(Prev);
7030 // A declaration in the translation unit can conflict with an extern "C"
7032 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit())
7033 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous);
7035 // An extern "C" declaration can conflict with a declaration in the
7036 // translation unit or can be a redeclaration of an extern "C" declaration
7037 // in another scope.
7038 if (isIncompleteDeclExternC(S,ND))
7039 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous);
7041 // Neither global nor extern "C": nothing to do.
7045 void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
7046 // If the decl is already known invalid, don't check it.
7047 if (NewVD->isInvalidDecl())
7050 TypeSourceInfo *TInfo = NewVD->getTypeSourceInfo();
7051 QualType T = TInfo->getType();
7053 // Defer checking an 'auto' type until its initializer is attached.
7054 if (T->isUndeducedType())
7057 if (NewVD->hasAttrs())
7058 CheckAlignasUnderalignment(NewVD);
7060 if (T->isObjCObjectType()) {
7061 Diag(NewVD->getLocation(), diag::err_statically_allocated_object)
7062 << FixItHint::CreateInsertion(NewVD->getLocation(), "*");
7063 T = Context.getObjCObjectPointerType(T);
7067 // Emit an error if an address space was applied to decl with local storage.
7068 // This includes arrays of objects with address space qualifiers, but not
7069 // automatic variables that point to other address spaces.
7070 // ISO/IEC TR 18037 S5.1.2
7071 if (!getLangOpts().OpenCL
7072 && NewVD->hasLocalStorage() && T.getAddressSpace() != 0) {
7073 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl);
7074 NewVD->setInvalidDecl();
7078 // OpenCL v1.2 s6.8 - The static qualifier is valid only in program
7080 if (getLangOpts().OpenCLVersion == 120 &&
7081 !getOpenCLOptions().isEnabled("cl_clang_storage_class_specifiers") &&
7082 NewVD->isStaticLocal()) {
7083 Diag(NewVD->getLocation(), diag::err_static_function_scope);
7084 NewVD->setInvalidDecl();
7088 if (getLangOpts().OpenCL) {
7089 // OpenCL v2.0 s6.12.5 - The __block storage type is not supported.
7090 if (NewVD->hasAttr<BlocksAttr>()) {
7091 Diag(NewVD->getLocation(), diag::err_opencl_block_storage_type);
7095 if (T->isBlockPointerType()) {
7096 // OpenCL v2.0 s6.12.5 - Any block declaration must be const qualified and
7097 // can't use 'extern' storage class.
7098 if (!T.isConstQualified()) {
7099 Diag(NewVD->getLocation(), diag::err_opencl_invalid_block_declaration)
7101 NewVD->setInvalidDecl();
7104 if (NewVD->hasExternalStorage()) {
7105 Diag(NewVD->getLocation(), diag::err_opencl_extern_block_declaration);
7106 NewVD->setInvalidDecl();
7110 // OpenCL v1.2 s6.5 - All program scope variables must be declared in the
7111 // __constant address space.
7112 // OpenCL v2.0 s6.5.1 - Variables defined at program scope and static
7113 // variables inside a function can also be declared in the global
7115 if (NewVD->isFileVarDecl() || NewVD->isStaticLocal() ||
7116 NewVD->hasExternalStorage()) {
7117 if (!T->isSamplerT() &&
7118 !(T.getAddressSpace() == LangAS::opencl_constant ||
7119 (T.getAddressSpace() == LangAS::opencl_global &&
7120 getLangOpts().OpenCLVersion == 200))) {
7121 int Scope = NewVD->isStaticLocal() | NewVD->hasExternalStorage() << 1;
7122 if (getLangOpts().OpenCLVersion == 200)
7123 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
7124 << Scope << "global or constant";
7126 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
7127 << Scope << "constant";
7128 NewVD->setInvalidDecl();
7132 if (T.getAddressSpace() == LangAS::opencl_global) {
7133 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
7134 << 1 /*is any function*/ << "global";
7135 NewVD->setInvalidDecl();
7138 // OpenCL v1.1 s6.5.2 and s6.5.3 no local or constant variables
7140 if (T.getAddressSpace() == LangAS::opencl_constant ||
7141 T.getAddressSpace() == LangAS::opencl_local) {
7142 FunctionDecl *FD = getCurFunctionDecl();
7143 if (FD && !FD->hasAttr<OpenCLKernelAttr>()) {
7144 if (T.getAddressSpace() == LangAS::opencl_constant)
7145 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
7146 << 0 /*non-kernel only*/ << "constant";
7148 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
7149 << 0 /*non-kernel only*/ << "local";
7150 NewVD->setInvalidDecl();
7157 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()
7158 && !NewVD->hasAttr<BlocksAttr>()) {
7159 if (getLangOpts().getGC() != LangOptions::NonGC)
7160 Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local);
7162 assert(!getLangOpts().ObjCAutoRefCount);
7163 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
7167 bool isVM = T->isVariablyModifiedType();
7168 if (isVM || NewVD->hasAttr<CleanupAttr>() ||
7169 NewVD->hasAttr<BlocksAttr>())
7170 getCurFunction()->setHasBranchProtectedScope();
7172 if ((isVM && NewVD->hasLinkage()) ||
7173 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) {
7174 bool SizeIsNegative;
7175 llvm::APSInt Oversized;
7176 TypeSourceInfo *FixedTInfo =
7177 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
7178 SizeIsNegative, Oversized);
7179 if (!FixedTInfo && T->isVariableArrayType()) {
7180 const VariableArrayType *VAT = Context.getAsVariableArrayType(T);
7181 // FIXME: This won't give the correct result for
7183 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange();
7185 if (NewVD->isFileVarDecl())
7186 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope)
7188 else if (NewVD->isStaticLocal())
7189 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage)
7192 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage)
7194 NewVD->setInvalidDecl();
7199 if (NewVD->isFileVarDecl())
7200 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope);
7202 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage);
7203 NewVD->setInvalidDecl();
7207 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size);
7208 NewVD->setType(FixedTInfo->getType());
7209 NewVD->setTypeSourceInfo(FixedTInfo);
7212 if (T->isVoidType()) {
7213 // C++98 [dcl.stc]p5: The extern specifier can be applied only to the names
7214 // of objects and functions.
7215 if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) {
7216 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type)
7218 NewVD->setInvalidDecl();
7223 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) {
7224 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal);
7225 NewVD->setInvalidDecl();
7229 if (isVM && NewVD->hasAttr<BlocksAttr>()) {
7230 Diag(NewVD->getLocation(), diag::err_block_on_vm);
7231 NewVD->setInvalidDecl();
7235 if (NewVD->isConstexpr() && !T->isDependentType() &&
7236 RequireLiteralType(NewVD->getLocation(), T,
7237 diag::err_constexpr_var_non_literal)) {
7238 NewVD->setInvalidDecl();
7243 /// \brief Perform semantic checking on a newly-created variable
7246 /// This routine performs all of the type-checking required for a
7247 /// variable declaration once it has been built. It is used both to
7248 /// check variables after they have been parsed and their declarators
7249 /// have been translated into a declaration, and to check variables
7250 /// that have been instantiated from a template.
7252 /// Sets NewVD->isInvalidDecl() if an error was encountered.
7254 /// Returns true if the variable declaration is a redeclaration.
7255 bool Sema::CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous) {
7256 CheckVariableDeclarationType(NewVD);
7258 // If the decl is already known invalid, don't check it.
7259 if (NewVD->isInvalidDecl())
7262 // If we did not find anything by this name, look for a non-visible
7263 // extern "C" declaration with the same name.
7264 if (Previous.empty() &&
7265 checkForConflictWithNonVisibleExternC(*this, NewVD, Previous))
7266 Previous.setShadowed();
7268 if (!Previous.empty()) {
7269 MergeVarDecl(NewVD, Previous);
7276 struct FindOverriddenMethod {
7278 CXXMethodDecl *Method;
7280 /// Member lookup function that determines whether a given C++
7281 /// method overrides a method in a base class, to be used with
7282 /// CXXRecordDecl::lookupInBases().
7283 bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
7284 RecordDecl *BaseRecord =
7285 Specifier->getType()->getAs<RecordType>()->getDecl();
7287 DeclarationName Name = Method->getDeclName();
7289 // FIXME: Do we care about other names here too?
7290 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7291 // We really want to find the base class destructor here.
7292 QualType T = S->Context.getTypeDeclType(BaseRecord);
7293 CanQualType CT = S->Context.getCanonicalType(T);
7295 Name = S->Context.DeclarationNames.getCXXDestructorName(CT);
7298 for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
7299 Path.Decls = Path.Decls.slice(1)) {
7300 NamedDecl *D = Path.Decls.front();
7301 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
7302 if (MD->isVirtual() && !S->IsOverload(Method, MD, false))
7311 enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted };
7312 } // end anonymous namespace
7314 /// \brief Report an error regarding overriding, along with any relevant
7315 /// overriden methods.
7317 /// \param DiagID the primary error to report.
7318 /// \param MD the overriding method.
7319 /// \param OEK which overrides to include as notes.
7320 static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD,
7321 OverrideErrorKind OEK = OEK_All) {
7322 S.Diag(MD->getLocation(), DiagID) << MD->getDeclName();
7323 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
7324 E = MD->end_overridden_methods();
7326 // This check (& the OEK parameter) could be replaced by a predicate, but
7327 // without lambdas that would be overkill. This is still nicer than writing
7328 // out the diag loop 3 times.
7329 if ((OEK == OEK_All) ||
7330 (OEK == OEK_NonDeleted && !(*I)->isDeleted()) ||
7331 (OEK == OEK_Deleted && (*I)->isDeleted()))
7332 S.Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
7336 /// AddOverriddenMethods - See if a method overrides any in the base classes,
7337 /// and if so, check that it's a valid override and remember it.
7338 bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) {
7339 // Look for methods in base classes that this method might override.
7341 FindOverriddenMethod FOM;
7344 bool hasDeletedOverridenMethods = false;
7345 bool hasNonDeletedOverridenMethods = false;
7346 bool AddedAny = false;
7347 if (DC->lookupInBases(FOM, Paths)) {
7348 for (auto *I : Paths.found_decls()) {
7349 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(I)) {
7350 MD->addOverriddenMethod(OldMD->getCanonicalDecl());
7351 if (!CheckOverridingFunctionReturnType(MD, OldMD) &&
7352 !CheckOverridingFunctionAttributes(MD, OldMD) &&
7353 !CheckOverridingFunctionExceptionSpec(MD, OldMD) &&
7354 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) {
7355 hasDeletedOverridenMethods |= OldMD->isDeleted();
7356 hasNonDeletedOverridenMethods |= !OldMD->isDeleted();
7363 if (hasDeletedOverridenMethods && !MD->isDeleted()) {
7364 ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted);
7366 if (hasNonDeletedOverridenMethods && MD->isDeleted()) {
7367 ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted);
7374 // Struct for holding all of the extra arguments needed by
7375 // DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator.
7376 struct ActOnFDArgs {
7379 MultiTemplateParamsArg TemplateParamLists;
7382 } // end anonymous namespace
7386 // Callback to only accept typo corrections that have a non-zero edit distance.
7387 // Also only accept corrections that have the same parent decl.
7388 class DifferentNameValidatorCCC : public CorrectionCandidateCallback {
7390 DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD,
7391 CXXRecordDecl *Parent)
7392 : Context(Context), OriginalFD(TypoFD),
7393 ExpectedParent(Parent ? Parent->getCanonicalDecl() : nullptr) {}
7395 bool ValidateCandidate(const TypoCorrection &candidate) override {
7396 if (candidate.getEditDistance() == 0)
7399 SmallVector<unsigned, 1> MismatchedParams;
7400 for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(),
7401 CDeclEnd = candidate.end();
7402 CDecl != CDeclEnd; ++CDecl) {
7403 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7405 if (FD && !FD->hasBody() &&
7406 hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) {
7407 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
7408 CXXRecordDecl *Parent = MD->getParent();
7409 if (Parent && Parent->getCanonicalDecl() == ExpectedParent)
7411 } else if (!ExpectedParent) {
7421 ASTContext &Context;
7422 FunctionDecl *OriginalFD;
7423 CXXRecordDecl *ExpectedParent;
7426 } // end anonymous namespace
7428 void Sema::MarkTypoCorrectedFunctionDefinition(const NamedDecl *F) {
7429 TypoCorrectedFunctionDefinitions.insert(F);
7432 /// \brief Generate diagnostics for an invalid function redeclaration.
7434 /// This routine handles generating the diagnostic messages for an invalid
7435 /// function redeclaration, including finding possible similar declarations
7436 /// or performing typo correction if there are no previous declarations with
7439 /// Returns a NamedDecl iff typo correction was performed and substituting in
7440 /// the new declaration name does not cause new errors.
7441 static NamedDecl *DiagnoseInvalidRedeclaration(
7442 Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD,
7443 ActOnFDArgs &ExtraArgs, bool IsLocalFriend, Scope *S) {
7444 DeclarationName Name = NewFD->getDeclName();
7445 DeclContext *NewDC = NewFD->getDeclContext();
7446 SmallVector<unsigned, 1> MismatchedParams;
7447 SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches;
7448 TypoCorrection Correction;
7449 bool IsDefinition = ExtraArgs.D.isFunctionDefinition();
7450 unsigned DiagMsg = IsLocalFriend ? diag::err_no_matching_local_friend
7451 : diag::err_member_decl_does_not_match;
7452 LookupResult Prev(SemaRef, Name, NewFD->getLocation(),
7453 IsLocalFriend ? Sema::LookupLocalFriendName
7454 : Sema::LookupOrdinaryName,
7455 Sema::ForRedeclaration);
7457 NewFD->setInvalidDecl();
7459 SemaRef.LookupName(Prev, S);
7461 SemaRef.LookupQualifiedName(Prev, NewDC);
7462 assert(!Prev.isAmbiguous() &&
7463 "Cannot have an ambiguity in previous-declaration lookup");
7464 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
7465 if (!Prev.empty()) {
7466 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end();
7467 Func != FuncEnd; ++Func) {
7468 FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func);
7470 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7471 // Add 1 to the index so that 0 can mean the mismatch didn't
7472 // involve a parameter
7474 MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1;
7475 NearMatches.push_back(std::make_pair(FD, ParamNum));
7478 // If the qualified name lookup yielded nothing, try typo correction
7479 } else if ((Correction = SemaRef.CorrectTypo(
7480 Prev.getLookupNameInfo(), Prev.getLookupKind(), S,
7481 &ExtraArgs.D.getCXXScopeSpec(),
7482 llvm::make_unique<DifferentNameValidatorCCC>(
7483 SemaRef.Context, NewFD, MD ? MD->getParent() : nullptr),
7484 Sema::CTK_ErrorRecovery, IsLocalFriend ? nullptr : NewDC))) {
7485 // Set up everything for the call to ActOnFunctionDeclarator
7486 ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(),
7487 ExtraArgs.D.getIdentifierLoc());
7489 Previous.setLookupName(Correction.getCorrection());
7490 for (TypoCorrection::decl_iterator CDecl = Correction.begin(),
7491 CDeclEnd = Correction.end();
7492 CDecl != CDeclEnd; ++CDecl) {
7493 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7494 if (FD && !FD->hasBody() &&
7495 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7496 Previous.addDecl(FD);
7499 bool wasRedeclaration = ExtraArgs.D.isRedeclaration();
7502 // Retry building the function declaration with the new previous
7503 // declarations, and with errors suppressed.
7506 Sema::SFINAETrap Trap(SemaRef);
7508 // TODO: Refactor ActOnFunctionDeclarator so that we can call only the
7509 // pieces need to verify the typo-corrected C++ declaration and hopefully
7510 // eliminate the need for the parameter pack ExtraArgs.
7511 Result = SemaRef.ActOnFunctionDeclarator(
7512 ExtraArgs.S, ExtraArgs.D,
7513 Correction.getCorrectionDecl()->getDeclContext(),
7514 NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists,
7515 ExtraArgs.AddToScope);
7517 if (Trap.hasErrorOccurred())
7522 // Determine which correction we picked.
7523 Decl *Canonical = Result->getCanonicalDecl();
7524 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
7526 if ((*I)->getCanonicalDecl() == Canonical)
7527 Correction.setCorrectionDecl(*I);
7529 // Let Sema know about the correction.
7530 SemaRef.MarkTypoCorrectedFunctionDefinition(Result);
7531 SemaRef.diagnoseTypo(
7533 SemaRef.PDiag(IsLocalFriend
7534 ? diag::err_no_matching_local_friend_suggest
7535 : diag::err_member_decl_does_not_match_suggest)
7536 << Name << NewDC << IsDefinition);
7540 // Pretend the typo correction never occurred
7541 ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(),
7542 ExtraArgs.D.getIdentifierLoc());
7543 ExtraArgs.D.setRedeclaration(wasRedeclaration);
7545 Previous.setLookupName(Name);
7548 SemaRef.Diag(NewFD->getLocation(), DiagMsg)
7549 << Name << NewDC << IsDefinition << NewFD->getLocation();
7551 bool NewFDisConst = false;
7552 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD))
7553 NewFDisConst = NewMD->isConst();
7555 for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator
7556 NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end();
7557 NearMatch != NearMatchEnd; ++NearMatch) {
7558 FunctionDecl *FD = NearMatch->first;
7559 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
7560 bool FDisConst = MD && MD->isConst();
7561 bool IsMember = MD || !IsLocalFriend;
7563 // FIXME: These notes are poorly worded for the local friend case.
7564 if (unsigned Idx = NearMatch->second) {
7565 ParmVarDecl *FDParam = FD->getParamDecl(Idx-1);
7566 SourceLocation Loc = FDParam->getTypeSpecStartLoc();
7567 if (Loc.isInvalid()) Loc = FD->getLocation();
7568 SemaRef.Diag(Loc, IsMember ? diag::note_member_def_close_param_match
7569 : diag::note_local_decl_close_param_match)
7570 << Idx << FDParam->getType()
7571 << NewFD->getParamDecl(Idx - 1)->getType();
7572 } else if (FDisConst != NewFDisConst) {
7573 SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match)
7574 << NewFDisConst << FD->getSourceRange().getEnd();
7576 SemaRef.Diag(FD->getLocation(),
7577 IsMember ? diag::note_member_def_close_match
7578 : diag::note_local_decl_close_match);
7583 static StorageClass getFunctionStorageClass(Sema &SemaRef, Declarator &D) {
7584 switch (D.getDeclSpec().getStorageClassSpec()) {
7585 default: llvm_unreachable("Unknown storage class!");
7586 case DeclSpec::SCS_auto:
7587 case DeclSpec::SCS_register:
7588 case DeclSpec::SCS_mutable:
7589 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7590 diag::err_typecheck_sclass_func);
7591 D.getMutableDeclSpec().ClearStorageClassSpecs();
7594 case DeclSpec::SCS_unspecified: break;
7595 case DeclSpec::SCS_extern:
7596 if (D.getDeclSpec().isExternInLinkageSpec())
7599 case DeclSpec::SCS_static: {
7600 if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) {
7602 // The declaration of an identifier for a function that has
7603 // block scope shall have no explicit storage-class specifier
7604 // other than extern
7605 // See also (C++ [dcl.stc]p4).
7606 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7607 diag::err_static_block_func);
7612 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
7615 // No explicit storage class has already been returned
7619 static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
7620 DeclContext *DC, QualType &R,
7621 TypeSourceInfo *TInfo,
7623 bool &IsVirtualOkay) {
7624 DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D);
7625 DeclarationName Name = NameInfo.getName();
7627 FunctionDecl *NewFD = nullptr;
7628 bool isInline = D.getDeclSpec().isInlineSpecified();
7630 if (!SemaRef.getLangOpts().CPlusPlus) {
7631 // Determine whether the function was written with a
7632 // prototype. This true when:
7633 // - there is a prototype in the declarator, or
7634 // - the type R of the function is some kind of typedef or other non-
7635 // attributed reference to a type name (which eventually refers to a
7638 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) ||
7639 (!R->getAsAdjusted<FunctionType>() && R->isFunctionProtoType());
7641 NewFD = FunctionDecl::Create(SemaRef.Context, DC,
7642 D.getLocStart(), NameInfo, R,
7643 TInfo, SC, isInline,
7644 HasPrototype, false);
7645 if (D.isInvalidType())
7646 NewFD->setInvalidDecl();
7651 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
7652 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
7654 // Check that the return type is not an abstract class type.
7655 // For record types, this is done by the AbstractClassUsageDiagnoser once
7656 // the class has been completely parsed.
7657 if (!DC->isRecord() &&
7658 SemaRef.RequireNonAbstractType(
7659 D.getIdentifierLoc(), R->getAs<FunctionType>()->getReturnType(),
7660 diag::err_abstract_type_in_decl, SemaRef.AbstractReturnType))
7663 if (Name.getNameKind() == DeclarationName::CXXConstructorName) {
7664 // This is a C++ constructor declaration.
7665 assert(DC->isRecord() &&
7666 "Constructors can only be declared in a member context");
7668 R = SemaRef.CheckConstructorDeclarator(D, R, SC);
7669 return CXXConstructorDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7670 D.getLocStart(), NameInfo,
7671 R, TInfo, isExplicit, isInline,
7672 /*isImplicitlyDeclared=*/false,
7675 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7676 // This is a C++ destructor declaration.
7677 if (DC->isRecord()) {
7678 R = SemaRef.CheckDestructorDeclarator(D, R, SC);
7679 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
7680 CXXDestructorDecl *NewDD = CXXDestructorDecl::Create(
7681 SemaRef.Context, Record,
7683 NameInfo, R, TInfo, isInline,
7684 /*isImplicitlyDeclared=*/false);
7686 // If the class is complete, then we now create the implicit exception
7687 // specification. If the class is incomplete or dependent, we can't do
7689 if (SemaRef.getLangOpts().CPlusPlus11 && !Record->isDependentType() &&
7690 Record->getDefinition() && !Record->isBeingDefined() &&
7691 R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) {
7692 SemaRef.AdjustDestructorExceptionSpec(Record, NewDD);
7695 IsVirtualOkay = true;
7699 SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member);
7702 // Create a FunctionDecl to satisfy the function definition parsing
7704 return FunctionDecl::Create(SemaRef.Context, DC,
7706 D.getIdentifierLoc(), Name, R, TInfo,
7708 /*hasPrototype=*/true, isConstexpr);
7711 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
7712 if (!DC->isRecord()) {
7713 SemaRef.Diag(D.getIdentifierLoc(),
7714 diag::err_conv_function_not_member);
7718 SemaRef.CheckConversionDeclarator(D, R, SC);
7719 IsVirtualOkay = true;
7720 return CXXConversionDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7721 D.getLocStart(), NameInfo,
7722 R, TInfo, isInline, isExplicit,
7723 isConstexpr, SourceLocation());
7725 } else if (Name.getNameKind() == DeclarationName::CXXDeductionGuideName) {
7726 SemaRef.CheckDeductionGuideDeclarator(D, R, SC);
7728 return CXXDeductionGuideDecl::Create(SemaRef.Context, DC, D.getLocStart(),
7729 isExplicit, NameInfo, R, TInfo,
7731 } else if (DC->isRecord()) {
7732 // If the name of the function is the same as the name of the record,
7733 // then this must be an invalid constructor that has a return type.
7734 // (The parser checks for a return type and makes the declarator a
7735 // constructor if it has no return type).
7736 if (Name.getAsIdentifierInfo() &&
7737 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){
7738 SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type)
7739 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
7740 << SourceRange(D.getIdentifierLoc());
7744 // This is a C++ method declaration.
7745 CXXMethodDecl *Ret = CXXMethodDecl::Create(SemaRef.Context,
7746 cast<CXXRecordDecl>(DC),
7747 D.getLocStart(), NameInfo, R,
7748 TInfo, SC, isInline,
7749 isConstexpr, SourceLocation());
7750 IsVirtualOkay = !Ret->isStatic();
7754 SemaRef.getLangOpts().CPlusPlus && D.getDeclSpec().isFriendSpecified();
7755 if (!isFriend && SemaRef.CurContext->isRecord())
7758 // Determine whether the function was written with a
7759 // prototype. This true when:
7760 // - we're in C++ (where every function has a prototype),
7761 return FunctionDecl::Create(SemaRef.Context, DC,
7763 NameInfo, R, TInfo, SC, isInline,
7764 true/*HasPrototype*/, isConstexpr);
7768 enum OpenCLParamType {
7772 InvalidAddrSpacePtrKernelParam,
7777 static OpenCLParamType getOpenCLKernelParameterType(Sema &S, QualType PT) {
7778 if (PT->isPointerType()) {
7779 QualType PointeeType = PT->getPointeeType();
7780 if (PointeeType->isPointerType())
7781 return PtrPtrKernelParam;
7782 if (PointeeType.getAddressSpace() == LangAS::opencl_generic ||
7783 PointeeType.getAddressSpace() == 0)
7784 return InvalidAddrSpacePtrKernelParam;
7785 return PtrKernelParam;
7788 // TODO: Forbid the other integer types (size_t, ptrdiff_t...) when they can
7789 // be used as builtin types.
7791 if (PT->isImageType())
7792 return PtrKernelParam;
7794 if (PT->isBooleanType())
7795 return InvalidKernelParam;
7798 return InvalidKernelParam;
7800 // OpenCL extension spec v1.2 s9.5:
7801 // This extension adds support for half scalar and vector types as built-in
7802 // types that can be used for arithmetic operations, conversions etc.
7803 if (!S.getOpenCLOptions().isEnabled("cl_khr_fp16") && PT->isHalfType())
7804 return InvalidKernelParam;
7806 if (PT->isRecordType())
7807 return RecordKernelParam;
7809 return ValidKernelParam;
7812 static void checkIsValidOpenCLKernelParameter(
7816 llvm::SmallPtrSetImpl<const Type *> &ValidTypes) {
7817 QualType PT = Param->getType();
7819 // Cache the valid types we encounter to avoid rechecking structs that are
7821 if (ValidTypes.count(PT.getTypePtr()))
7824 switch (getOpenCLKernelParameterType(S, PT)) {
7825 case PtrPtrKernelParam:
7826 // OpenCL v1.2 s6.9.a:
7827 // A kernel function argument cannot be declared as a
7828 // pointer to a pointer type.
7829 S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param);
7833 case InvalidAddrSpacePtrKernelParam:
7834 // OpenCL v1.0 s6.5:
7835 // __kernel function arguments declared to be a pointer of a type can point
7836 // to one of the following address spaces only : __global, __local or
7838 S.Diag(Param->getLocation(), diag::err_kernel_arg_address_space);
7842 // OpenCL v1.2 s6.9.k:
7843 // Arguments to kernel functions in a program cannot be declared with the
7844 // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and
7845 // uintptr_t or a struct and/or union that contain fields declared to be
7846 // one of these built-in scalar types.
7848 case InvalidKernelParam:
7849 // OpenCL v1.2 s6.8 n:
7850 // A kernel function argument cannot be declared
7852 // Do not diagnose half type since it is diagnosed as invalid argument
7853 // type for any function elsewhere.
7854 if (!PT->isHalfType())
7855 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7859 case PtrKernelParam:
7860 case ValidKernelParam:
7861 ValidTypes.insert(PT.getTypePtr());
7864 case RecordKernelParam:
7868 // Track nested structs we will inspect
7869 SmallVector<const Decl *, 4> VisitStack;
7871 // Track where we are in the nested structs. Items will migrate from
7872 // VisitStack to HistoryStack as we do the DFS for bad field.
7873 SmallVector<const FieldDecl *, 4> HistoryStack;
7874 HistoryStack.push_back(nullptr);
7876 const RecordDecl *PD = PT->castAs<RecordType>()->getDecl();
7877 VisitStack.push_back(PD);
7879 assert(VisitStack.back() && "First decl null?");
7882 const Decl *Next = VisitStack.pop_back_val();
7884 assert(!HistoryStack.empty());
7885 // Found a marker, we have gone up a level
7886 if (const FieldDecl *Hist = HistoryStack.pop_back_val())
7887 ValidTypes.insert(Hist->getType().getTypePtr());
7892 // Adds everything except the original parameter declaration (which is not a
7893 // field itself) to the history stack.
7894 const RecordDecl *RD;
7895 if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) {
7896 HistoryStack.push_back(Field);
7897 RD = Field->getType()->castAs<RecordType>()->getDecl();
7899 RD = cast<RecordDecl>(Next);
7902 // Add a null marker so we know when we've gone back up a level
7903 VisitStack.push_back(nullptr);
7905 for (const auto *FD : RD->fields()) {
7906 QualType QT = FD->getType();
7908 if (ValidTypes.count(QT.getTypePtr()))
7911 OpenCLParamType ParamType = getOpenCLKernelParameterType(S, QT);
7912 if (ParamType == ValidKernelParam)
7915 if (ParamType == RecordKernelParam) {
7916 VisitStack.push_back(FD);
7920 // OpenCL v1.2 s6.9.p:
7921 // Arguments to kernel functions that are declared to be a struct or union
7922 // do not allow OpenCL objects to be passed as elements of the struct or
7924 if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam ||
7925 ParamType == InvalidAddrSpacePtrKernelParam) {
7926 S.Diag(Param->getLocation(),
7927 diag::err_record_with_pointers_kernel_param)
7928 << PT->isUnionType()
7931 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7934 S.Diag(PD->getLocation(), diag::note_within_field_of_type)
7935 << PD->getDeclName();
7937 // We have an error, now let's go back up through history and show where
7938 // the offending field came from
7939 for (ArrayRef<const FieldDecl *>::const_iterator
7940 I = HistoryStack.begin() + 1,
7941 E = HistoryStack.end();
7943 const FieldDecl *OuterField = *I;
7944 S.Diag(OuterField->getLocation(), diag::note_within_field_of_type)
7945 << OuterField->getType();
7948 S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here)
7949 << QT->isPointerType()
7954 } while (!VisitStack.empty());
7957 /// Find the DeclContext in which a tag is implicitly declared if we see an
7958 /// elaborated type specifier in the specified context, and lookup finds
7960 static DeclContext *getTagInjectionContext(DeclContext *DC) {
7961 while (!DC->isFileContext() && !DC->isFunctionOrMethod())
7962 DC = DC->getParent();
7966 /// Find the Scope in which a tag is implicitly declared if we see an
7967 /// elaborated type specifier in the specified context, and lookup finds
7969 static Scope *getTagInjectionScope(Scope *S, const LangOptions &LangOpts) {
7970 while (S->isClassScope() ||
7971 (LangOpts.CPlusPlus &&
7972 S->isFunctionPrototypeScope()) ||
7973 ((S->getFlags() & Scope::DeclScope) == 0) ||
7974 (S->getEntity() && S->getEntity()->isTransparentContext()))
7980 Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
7981 TypeSourceInfo *TInfo, LookupResult &Previous,
7982 MultiTemplateParamsArg TemplateParamLists,
7984 QualType R = TInfo->getType();
7986 assert(R.getTypePtr()->isFunctionType());
7988 // TODO: consider using NameInfo for diagnostic.
7989 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
7990 DeclarationName Name = NameInfo.getName();
7991 StorageClass SC = getFunctionStorageClass(*this, D);
7993 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
7994 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
7995 diag::err_invalid_thread)
7996 << DeclSpec::getSpecifierName(TSCS);
7998 if (D.isFirstDeclarationOfMember())
7999 adjustMemberFunctionCC(R, D.isStaticMember(), D.isCtorOrDtor(),
8000 D.getIdentifierLoc());
8002 bool isFriend = false;
8003 FunctionTemplateDecl *FunctionTemplate = nullptr;
8004 bool isMemberSpecialization = false;
8005 bool isFunctionTemplateSpecialization = false;
8007 bool isDependentClassScopeExplicitSpecialization = false;
8008 bool HasExplicitTemplateArgs = false;
8009 TemplateArgumentListInfo TemplateArgs;
8011 bool isVirtualOkay = false;
8013 DeclContext *OriginalDC = DC;
8014 bool IsLocalExternDecl = adjustContextForLocalExternDecl(DC);
8016 FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC,
8018 if (!NewFD) return nullptr;
8020 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer())
8021 NewFD->setTopLevelDeclInObjCContainer();
8023 // Set the lexical context. If this is a function-scope declaration, or has a
8024 // C++ scope specifier, or is the object of a friend declaration, the lexical
8025 // context will be different from the semantic context.
8026 NewFD->setLexicalDeclContext(CurContext);
8028 if (IsLocalExternDecl)
8029 NewFD->setLocalExternDecl();
8031 if (getLangOpts().CPlusPlus) {
8032 bool isInline = D.getDeclSpec().isInlineSpecified();
8033 bool isVirtual = D.getDeclSpec().isVirtualSpecified();
8034 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
8035 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
8036 bool isConcept = D.getDeclSpec().isConceptSpecified();
8037 isFriend = D.getDeclSpec().isFriendSpecified();
8038 if (isFriend && !isInline && D.isFunctionDefinition()) {
8039 // C++ [class.friend]p5
8040 // A function can be defined in a friend declaration of a
8041 // class . . . . Such a function is implicitly inline.
8042 NewFD->setImplicitlyInline();
8045 // If this is a method defined in an __interface, and is not a constructor
8046 // or an overloaded operator, then set the pure flag (isVirtual will already
8048 if (const CXXRecordDecl *Parent =
8049 dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) {
8050 if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided())
8051 NewFD->setPure(true);
8053 // C++ [class.union]p2
8054 // A union can have member functions, but not virtual functions.
8055 if (isVirtual && Parent->isUnion())
8056 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_in_union);
8059 SetNestedNameSpecifier(NewFD, D);
8060 isMemberSpecialization = false;
8061 isFunctionTemplateSpecialization = false;
8062 if (D.isInvalidType())
8063 NewFD->setInvalidDecl();
8065 // Match up the template parameter lists with the scope specifier, then
8066 // determine whether we have a template or a template specialization.
8067 bool Invalid = false;
8068 if (TemplateParameterList *TemplateParams =
8069 MatchTemplateParametersToScopeSpecifier(
8070 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
8071 D.getCXXScopeSpec(),
8072 D.getName().getKind() == UnqualifiedId::IK_TemplateId
8073 ? D.getName().TemplateId
8075 TemplateParamLists, isFriend, isMemberSpecialization,
8077 if (TemplateParams->size() > 0) {
8078 // This is a function template
8080 // Check that we can declare a template here.
8081 if (CheckTemplateDeclScope(S, TemplateParams))
8082 NewFD->setInvalidDecl();
8084 // A destructor cannot be a template.
8085 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
8086 Diag(NewFD->getLocation(), diag::err_destructor_template);
8087 NewFD->setInvalidDecl();
8090 // If we're adding a template to a dependent context, we may need to
8091 // rebuilding some of the types used within the template parameter list,
8092 // now that we know what the current instantiation is.
8093 if (DC->isDependentContext()) {
8094 ContextRAII SavedContext(*this, DC);
8095 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
8099 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC,
8100 NewFD->getLocation(),
8101 Name, TemplateParams,
8103 FunctionTemplate->setLexicalDeclContext(CurContext);
8104 NewFD->setDescribedFunctionTemplate(FunctionTemplate);
8106 // For source fidelity, store the other template param lists.
8107 if (TemplateParamLists.size() > 1) {
8108 NewFD->setTemplateParameterListsInfo(Context,
8109 TemplateParamLists.drop_back(1));
8112 // This is a function template specialization.
8113 isFunctionTemplateSpecialization = true;
8114 // For source fidelity, store all the template param lists.
8115 if (TemplateParamLists.size() > 0)
8116 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
8118 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);".
8120 // We want to remove the "template<>", found here.
8121 SourceRange RemoveRange = TemplateParams->getSourceRange();
8123 // If we remove the template<> and the name is not a
8124 // template-id, we're actually silently creating a problem:
8125 // the friend declaration will refer to an untemplated decl,
8126 // and clearly the user wants a template specialization. So
8127 // we need to insert '<>' after the name.
8128 SourceLocation InsertLoc;
8129 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
8130 InsertLoc = D.getName().getSourceRange().getEnd();
8131 InsertLoc = getLocForEndOfToken(InsertLoc);
8134 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend)
8135 << Name << RemoveRange
8136 << FixItHint::CreateRemoval(RemoveRange)
8137 << FixItHint::CreateInsertion(InsertLoc, "<>");
8142 // All template param lists were matched against the scope specifier:
8143 // this is NOT (an explicit specialization of) a template.
8144 if (TemplateParamLists.size() > 0)
8145 // For source fidelity, store all the template param lists.
8146 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
8150 NewFD->setInvalidDecl();
8151 if (FunctionTemplate)
8152 FunctionTemplate->setInvalidDecl();
8155 // C++ [dcl.fct.spec]p5:
8156 // The virtual specifier shall only be used in declarations of
8157 // nonstatic class member functions that appear within a
8158 // member-specification of a class declaration; see 10.3.
8160 if (isVirtual && !NewFD->isInvalidDecl()) {
8161 if (!isVirtualOkay) {
8162 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8163 diag::err_virtual_non_function);
8164 } else if (!CurContext->isRecord()) {
8165 // 'virtual' was specified outside of the class.
8166 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8167 diag::err_virtual_out_of_class)
8168 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
8169 } else if (NewFD->getDescribedFunctionTemplate()) {
8170 // C++ [temp.mem]p3:
8171 // A member function template shall not be virtual.
8172 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8173 diag::err_virtual_member_function_template)
8174 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
8176 // Okay: Add virtual to the method.
8177 NewFD->setVirtualAsWritten(true);
8180 if (getLangOpts().CPlusPlus14 &&
8181 NewFD->getReturnType()->isUndeducedType())
8182 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual);
8185 if (getLangOpts().CPlusPlus14 &&
8186 (NewFD->isDependentContext() ||
8187 (isFriend && CurContext->isDependentContext())) &&
8188 NewFD->getReturnType()->isUndeducedType()) {
8189 // If the function template is referenced directly (for instance, as a
8190 // member of the current instantiation), pretend it has a dependent type.
8191 // This is not really justified by the standard, but is the only sane
8193 // FIXME: For a friend function, we have not marked the function as being
8194 // a friend yet, so 'isDependentContext' on the FD doesn't work.
8195 const FunctionProtoType *FPT =
8196 NewFD->getType()->castAs<FunctionProtoType>();
8198 SubstAutoType(FPT->getReturnType(), Context.DependentTy);
8199 NewFD->setType(Context.getFunctionType(Result, FPT->getParamTypes(),
8200 FPT->getExtProtoInfo()));
8203 // C++ [dcl.fct.spec]p3:
8204 // The inline specifier shall not appear on a block scope function
8206 if (isInline && !NewFD->isInvalidDecl()) {
8207 if (CurContext->isFunctionOrMethod()) {
8208 // 'inline' is not allowed on block scope function declaration.
8209 Diag(D.getDeclSpec().getInlineSpecLoc(),
8210 diag::err_inline_declaration_block_scope) << Name
8211 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
8215 // C++ [dcl.fct.spec]p6:
8216 // The explicit specifier shall be used only in the declaration of a
8217 // constructor or conversion function within its class definition;
8218 // see 12.3.1 and 12.3.2.
8219 if (isExplicit && !NewFD->isInvalidDecl() &&
8220 !isa<CXXDeductionGuideDecl>(NewFD)) {
8221 if (!CurContext->isRecord()) {
8222 // 'explicit' was specified outside of the class.
8223 Diag(D.getDeclSpec().getExplicitSpecLoc(),
8224 diag::err_explicit_out_of_class)
8225 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
8226 } else if (!isa<CXXConstructorDecl>(NewFD) &&
8227 !isa<CXXConversionDecl>(NewFD)) {
8228 // 'explicit' was specified on a function that wasn't a constructor
8229 // or conversion function.
8230 Diag(D.getDeclSpec().getExplicitSpecLoc(),
8231 diag::err_explicit_non_ctor_or_conv_function)
8232 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
8237 // C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors
8238 // are implicitly inline.
8239 NewFD->setImplicitlyInline();
8241 // C++11 [dcl.constexpr]p3: functions declared constexpr are required to
8242 // be either constructors or to return a literal type. Therefore,
8243 // destructors cannot be declared constexpr.
8244 if (isa<CXXDestructorDecl>(NewFD))
8245 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor);
8249 // This is a function concept.
8250 if (FunctionTemplateDecl *FTD = NewFD->getDescribedFunctionTemplate())
8253 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
8254 // applied only to the definition of a function template [...]
8255 if (!D.isFunctionDefinition()) {
8256 Diag(D.getDeclSpec().getConceptSpecLoc(),
8257 diag::err_function_concept_not_defined);
8258 NewFD->setInvalidDecl();
8261 // C++ Concepts TS [dcl.spec.concept]p1: [...] A function concept shall
8262 // have no exception-specification and is treated as if it were specified
8263 // with noexcept(true) (15.4). [...]
8264 if (const FunctionProtoType *FPT = R->getAs<FunctionProtoType>()) {
8265 if (FPT->hasExceptionSpec()) {
8267 if (D.isFunctionDeclarator())
8268 Range = D.getFunctionTypeInfo().getExceptionSpecRange();
8269 Diag(NewFD->getLocation(), diag::err_function_concept_exception_spec)
8270 << FixItHint::CreateRemoval(Range);
8271 NewFD->setInvalidDecl();
8273 Context.adjustExceptionSpec(NewFD, EST_BasicNoexcept);
8276 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
8277 // following restrictions:
8278 // - The declared return type shall have the type bool.
8279 if (!Context.hasSameType(FPT->getReturnType(), Context.BoolTy)) {
8280 Diag(D.getIdentifierLoc(), diag::err_function_concept_bool_ret);
8281 NewFD->setInvalidDecl();
8284 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
8285 // following restrictions:
8286 // - The declaration's parameter list shall be equivalent to an empty
8288 if (FPT->getNumParams() > 0 || FPT->isVariadic())
8289 Diag(NewFD->getLocation(), diag::err_function_concept_with_params);
8292 // C++ Concepts TS [dcl.spec.concept]p2: Every concept definition is
8293 // implicity defined to be a constexpr declaration (implicitly inline)
8294 NewFD->setImplicitlyInline();
8296 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
8297 // be declared with the thread_local, inline, friend, or constexpr
8298 // specifiers, [...]
8300 Diag(D.getDeclSpec().getInlineSpecLoc(),
8301 diag::err_concept_decl_invalid_specifiers)
8303 NewFD->setInvalidDecl(true);
8307 Diag(D.getDeclSpec().getFriendSpecLoc(),
8308 diag::err_concept_decl_invalid_specifiers)
8310 NewFD->setInvalidDecl(true);
8314 Diag(D.getDeclSpec().getConstexprSpecLoc(),
8315 diag::err_concept_decl_invalid_specifiers)
8317 NewFD->setInvalidDecl(true);
8320 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
8321 // applied only to the definition of a function template or variable
8322 // template, declared in namespace scope.
8323 if (isFunctionTemplateSpecialization) {
8324 Diag(D.getDeclSpec().getConceptSpecLoc(),
8325 diag::err_concept_specified_specialization) << 1;
8326 NewFD->setInvalidDecl(true);
8331 // If __module_private__ was specified, mark the function accordingly.
8332 if (D.getDeclSpec().isModulePrivateSpecified()) {
8333 if (isFunctionTemplateSpecialization) {
8334 SourceLocation ModulePrivateLoc
8335 = D.getDeclSpec().getModulePrivateSpecLoc();
8336 Diag(ModulePrivateLoc, diag::err_module_private_specialization)
8338 << FixItHint::CreateRemoval(ModulePrivateLoc);
8340 NewFD->setModulePrivate();
8341 if (FunctionTemplate)
8342 FunctionTemplate->setModulePrivate();
8347 if (FunctionTemplate) {
8348 FunctionTemplate->setObjectOfFriendDecl();
8349 FunctionTemplate->setAccess(AS_public);
8351 NewFD->setObjectOfFriendDecl();
8352 NewFD->setAccess(AS_public);
8355 // If a function is defined as defaulted or deleted, mark it as such now.
8356 // FIXME: Does this ever happen? ActOnStartOfFunctionDef forces the function
8357 // definition kind to FDK_Definition.
8358 switch (D.getFunctionDefinitionKind()) {
8359 case FDK_Declaration:
8360 case FDK_Definition:
8364 NewFD->setDefaulted();
8368 NewFD->setDeletedAsWritten();
8372 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext &&
8373 D.isFunctionDefinition()) {
8374 // C++ [class.mfct]p2:
8375 // A member function may be defined (8.4) in its class definition, in
8376 // which case it is an inline member function (7.1.2)
8377 NewFD->setImplicitlyInline();
8380 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) &&
8381 !CurContext->isRecord()) {
8382 // C++ [class.static]p1:
8383 // A data or function member of a class may be declared static
8384 // in a class definition, in which case it is a static member of
8387 // Complain about the 'static' specifier if it's on an out-of-line
8388 // member function definition.
8389 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
8390 diag::err_static_out_of_line)
8391 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
8394 // C++11 [except.spec]p15:
8395 // A deallocation function with no exception-specification is treated
8396 // as if it were specified with noexcept(true).
8397 const FunctionProtoType *FPT = R->getAs<FunctionProtoType>();
8398 if ((Name.getCXXOverloadedOperator() == OO_Delete ||
8399 Name.getCXXOverloadedOperator() == OO_Array_Delete) &&
8400 getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec())
8401 NewFD->setType(Context.getFunctionType(
8402 FPT->getReturnType(), FPT->getParamTypes(),
8403 FPT->getExtProtoInfo().withExceptionSpec(EST_BasicNoexcept)));
8406 // Filter out previous declarations that don't match the scope.
8407 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewFD),
8408 D.getCXXScopeSpec().isNotEmpty() ||
8409 isMemberSpecialization ||
8410 isFunctionTemplateSpecialization);
8412 // Handle GNU asm-label extension (encoded as an attribute).
8413 if (Expr *E = (Expr*) D.getAsmLabel()) {
8414 // The parser guarantees this is a string.
8415 StringLiteral *SE = cast<StringLiteral>(E);
8416 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context,
8417 SE->getString(), 0));
8418 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
8419 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
8420 ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier());
8421 if (I != ExtnameUndeclaredIdentifiers.end()) {
8422 if (isDeclExternC(NewFD)) {
8423 NewFD->addAttr(I->second);
8424 ExtnameUndeclaredIdentifiers.erase(I);
8426 Diag(NewFD->getLocation(), diag::warn_redefine_extname_not_applied)
8427 << /*Variable*/0 << NewFD;
8431 // Copy the parameter declarations from the declarator D to the function
8432 // declaration NewFD, if they are available. First scavenge them into Params.
8433 SmallVector<ParmVarDecl*, 16> Params;
8435 if (D.isFunctionDeclarator(FTIIdx)) {
8436 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(FTIIdx).Fun;
8438 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs
8439 // function that takes no arguments, not a function that takes a
8440 // single void argument.
8441 // We let through "const void" here because Sema::GetTypeForDeclarator
8442 // already checks for that case.
8443 if (FTIHasNonVoidParameters(FTI) && FTI.Params[0].Param) {
8444 for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) {
8445 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
8446 assert(Param->getDeclContext() != NewFD && "Was set before ?");
8447 Param->setDeclContext(NewFD);
8448 Params.push_back(Param);
8450 if (Param->isInvalidDecl())
8451 NewFD->setInvalidDecl();
8455 if (!getLangOpts().CPlusPlus) {
8456 // In C, find all the tag declarations from the prototype and move them
8457 // into the function DeclContext. Remove them from the surrounding tag
8458 // injection context of the function, which is typically but not always
8460 DeclContext *PrototypeTagContext =
8461 getTagInjectionContext(NewFD->getLexicalDeclContext());
8462 for (NamedDecl *NonParmDecl : FTI.getDeclsInPrototype()) {
8463 auto *TD = dyn_cast<TagDecl>(NonParmDecl);
8465 // We don't want to reparent enumerators. Look at their parent enum
8468 if (auto *ECD = dyn_cast<EnumConstantDecl>(NonParmDecl))
8469 TD = cast<EnumDecl>(ECD->getDeclContext());
8473 DeclContext *TagDC = TD->getLexicalDeclContext();
8474 if (!TagDC->containsDecl(TD))
8476 TagDC->removeDecl(TD);
8477 TD->setDeclContext(NewFD);
8480 // Preserve the lexical DeclContext if it is not the surrounding tag
8481 // injection context of the FD. In this example, the semantic context of
8482 // E will be f and the lexical context will be S, while both the
8483 // semantic and lexical contexts of S will be f:
8484 // void f(struct S { enum E { a } f; } s);
8485 if (TagDC != PrototypeTagContext)
8486 TD->setLexicalDeclContext(TagDC);
8489 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) {
8490 // When we're declaring a function with a typedef, typeof, etc as in the
8491 // following example, we'll need to synthesize (unnamed)
8492 // parameters for use in the declaration.
8495 // typedef void fn(int);
8499 // Synthesize a parameter for each argument type.
8500 for (const auto &AI : FT->param_types()) {
8501 ParmVarDecl *Param =
8502 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), AI);
8503 Param->setScopeInfo(0, Params.size());
8504 Params.push_back(Param);
8507 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 &&
8508 "Should not need args for typedef of non-prototype fn");
8511 // Finally, we know we have the right number of parameters, install them.
8512 NewFD->setParams(Params);
8514 if (D.getDeclSpec().isNoreturnSpecified())
8516 ::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(),
8519 // Functions returning a variably modified type violate C99 6.7.5.2p2
8520 // because all functions have linkage.
8521 if (!NewFD->isInvalidDecl() &&
8522 NewFD->getReturnType()->isVariablyModifiedType()) {
8523 Diag(NewFD->getLocation(), diag::err_vm_func_decl);
8524 NewFD->setInvalidDecl();
8527 // Apply an implicit SectionAttr if #pragma code_seg is active.
8528 if (CodeSegStack.CurrentValue && D.isFunctionDefinition() &&
8529 !NewFD->hasAttr<SectionAttr>()) {
8531 SectionAttr::CreateImplicit(Context, SectionAttr::Declspec_allocate,
8532 CodeSegStack.CurrentValue->getString(),
8533 CodeSegStack.CurrentPragmaLocation));
8534 if (UnifySection(CodeSegStack.CurrentValue->getString(),
8535 ASTContext::PSF_Implicit | ASTContext::PSF_Execute |
8536 ASTContext::PSF_Read,
8538 NewFD->dropAttr<SectionAttr>();
8541 // Handle attributes.
8542 ProcessDeclAttributes(S, NewFD, D);
8544 if (getLangOpts().OpenCL) {
8545 // OpenCL v1.1 s6.5: Using an address space qualifier in a function return
8546 // type declaration will generate a compilation error.
8547 unsigned AddressSpace = NewFD->getReturnType().getAddressSpace();
8548 if (AddressSpace == LangAS::opencl_local ||
8549 AddressSpace == LangAS::opencl_global ||
8550 AddressSpace == LangAS::opencl_constant) {
8551 Diag(NewFD->getLocation(),
8552 diag::err_opencl_return_value_with_address_space);
8553 NewFD->setInvalidDecl();
8557 if (!getLangOpts().CPlusPlus) {
8558 // Perform semantic checking on the function declaration.
8559 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8560 CheckMain(NewFD, D.getDeclSpec());
8562 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8563 CheckMSVCRTEntryPoint(NewFD);
8565 if (!NewFD->isInvalidDecl())
8566 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8567 isMemberSpecialization));
8568 else if (!Previous.empty())
8569 // Recover gracefully from an invalid redeclaration.
8570 D.setRedeclaration(true);
8571 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8572 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8573 "previous declaration set still overloaded");
8575 // Diagnose no-prototype function declarations with calling conventions that
8576 // don't support variadic calls. Only do this in C and do it after merging
8577 // possibly prototyped redeclarations.
8578 const FunctionType *FT = NewFD->getType()->castAs<FunctionType>();
8579 if (isa<FunctionNoProtoType>(FT) && !D.isFunctionDefinition()) {
8580 CallingConv CC = FT->getExtInfo().getCC();
8581 if (!supportsVariadicCall(CC)) {
8582 // Windows system headers sometimes accidentally use stdcall without
8583 // (void) parameters, so we relax this to a warning.
8585 CC == CC_X86StdCall ? diag::warn_cconv_knr : diag::err_cconv_knr;
8586 Diag(NewFD->getLocation(), DiagID)
8587 << FunctionType::getNameForCallConv(CC);
8591 // C++11 [replacement.functions]p3:
8592 // The program's definitions shall not be specified as inline.
8594 // N.B. We diagnose declarations instead of definitions per LWG issue 2340.
8596 // Suppress the diagnostic if the function is __attribute__((used)), since
8597 // that forces an external definition to be emitted.
8598 if (D.getDeclSpec().isInlineSpecified() &&
8599 NewFD->isReplaceableGlobalAllocationFunction() &&
8600 !NewFD->hasAttr<UsedAttr>())
8601 Diag(D.getDeclSpec().getInlineSpecLoc(),
8602 diag::ext_operator_new_delete_declared_inline)
8603 << NewFD->getDeclName();
8605 // If the declarator is a template-id, translate the parser's template
8606 // argument list into our AST format.
8607 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
8608 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
8609 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
8610 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
8611 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
8612 TemplateId->NumArgs);
8613 translateTemplateArguments(TemplateArgsPtr,
8616 HasExplicitTemplateArgs = true;
8618 if (NewFD->isInvalidDecl()) {
8619 HasExplicitTemplateArgs = false;
8620 } else if (FunctionTemplate) {
8621 // Function template with explicit template arguments.
8622 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec)
8623 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc);
8625 HasExplicitTemplateArgs = false;
8627 assert((isFunctionTemplateSpecialization ||
8628 D.getDeclSpec().isFriendSpecified()) &&
8629 "should have a 'template<>' for this decl");
8630 // "friend void foo<>(int);" is an implicit specialization decl.
8631 isFunctionTemplateSpecialization = true;
8633 } else if (isFriend && isFunctionTemplateSpecialization) {
8634 // This combination is only possible in a recovery case; the user
8635 // wrote something like:
8636 // template <> friend void foo(int);
8637 // which we're recovering from as if the user had written:
8638 // friend void foo<>(int);
8639 // Go ahead and fake up a template id.
8640 HasExplicitTemplateArgs = true;
8641 TemplateArgs.setLAngleLoc(D.getIdentifierLoc());
8642 TemplateArgs.setRAngleLoc(D.getIdentifierLoc());
8645 // We do not add HD attributes to specializations here because
8646 // they may have different constexpr-ness compared to their
8647 // templates and, after maybeAddCUDAHostDeviceAttrs() is applied,
8648 // may end up with different effective targets. Instead, a
8649 // specialization inherits its target attributes from its template
8650 // in the CheckFunctionTemplateSpecialization() call below.
8651 if (getLangOpts().CUDA & !isFunctionTemplateSpecialization)
8652 maybeAddCUDAHostDeviceAttrs(NewFD, Previous);
8654 // If it's a friend (and only if it's a friend), it's possible
8655 // that either the specialized function type or the specialized
8656 // template is dependent, and therefore matching will fail. In
8657 // this case, don't check the specialization yet.
8658 bool InstantiationDependent = false;
8659 if (isFunctionTemplateSpecialization && isFriend &&
8660 (NewFD->getType()->isDependentType() || DC->isDependentContext() ||
8661 TemplateSpecializationType::anyDependentTemplateArguments(
8663 InstantiationDependent))) {
8664 assert(HasExplicitTemplateArgs &&
8665 "friend function specialization without template args");
8666 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs,
8668 NewFD->setInvalidDecl();
8669 } else if (isFunctionTemplateSpecialization) {
8670 if (CurContext->isDependentContext() && CurContext->isRecord()
8672 isDependentClassScopeExplicitSpecialization = true;
8673 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
8674 diag::ext_function_specialization_in_class :
8675 diag::err_function_specialization_in_class)
8676 << NewFD->getDeclName();
8677 } else if (CheckFunctionTemplateSpecialization(NewFD,
8678 (HasExplicitTemplateArgs ? &TemplateArgs
8681 NewFD->setInvalidDecl();
8684 // A storage-class-specifier shall not be specified in an explicit
8685 // specialization (14.7.3)
8686 FunctionTemplateSpecializationInfo *Info =
8687 NewFD->getTemplateSpecializationInfo();
8688 if (Info && SC != SC_None) {
8689 if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass())
8690 Diag(NewFD->getLocation(),
8691 diag::err_explicit_specialization_inconsistent_storage_class)
8693 << FixItHint::CreateRemoval(
8694 D.getDeclSpec().getStorageClassSpecLoc());
8697 Diag(NewFD->getLocation(),
8698 diag::ext_explicit_specialization_storage_class)
8699 << FixItHint::CreateRemoval(
8700 D.getDeclSpec().getStorageClassSpecLoc());
8702 } else if (isMemberSpecialization && isa<CXXMethodDecl>(NewFD)) {
8703 if (CheckMemberSpecialization(NewFD, Previous))
8704 NewFD->setInvalidDecl();
8707 // Perform semantic checking on the function declaration.
8708 if (!isDependentClassScopeExplicitSpecialization) {
8709 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8710 CheckMain(NewFD, D.getDeclSpec());
8712 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8713 CheckMSVCRTEntryPoint(NewFD);
8715 if (!NewFD->isInvalidDecl())
8716 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8717 isMemberSpecialization));
8718 else if (!Previous.empty())
8719 // Recover gracefully from an invalid redeclaration.
8720 D.setRedeclaration(true);
8723 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8724 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8725 "previous declaration set still overloaded");
8727 NamedDecl *PrincipalDecl = (FunctionTemplate
8728 ? cast<NamedDecl>(FunctionTemplate)
8731 if (isFriend && NewFD->getPreviousDecl()) {
8732 AccessSpecifier Access = AS_public;
8733 if (!NewFD->isInvalidDecl())
8734 Access = NewFD->getPreviousDecl()->getAccess();
8736 NewFD->setAccess(Access);
8737 if (FunctionTemplate) FunctionTemplate->setAccess(Access);
8740 if (NewFD->isOverloadedOperator() && !DC->isRecord() &&
8741 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
8742 PrincipalDecl->setNonMemberOperator();
8744 // If we have a function template, check the template parameter
8745 // list. This will check and merge default template arguments.
8746 if (FunctionTemplate) {
8747 FunctionTemplateDecl *PrevTemplate =
8748 FunctionTemplate->getPreviousDecl();
8749 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(),
8750 PrevTemplate ? PrevTemplate->getTemplateParameters()
8752 D.getDeclSpec().isFriendSpecified()
8753 ? (D.isFunctionDefinition()
8754 ? TPC_FriendFunctionTemplateDefinition
8755 : TPC_FriendFunctionTemplate)
8756 : (D.getCXXScopeSpec().isSet() &&
8757 DC && DC->isRecord() &&
8758 DC->isDependentContext())
8759 ? TPC_ClassTemplateMember
8760 : TPC_FunctionTemplate);
8763 if (NewFD->isInvalidDecl()) {
8764 // Ignore all the rest of this.
8765 } else if (!D.isRedeclaration()) {
8766 struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists,
8768 // Fake up an access specifier if it's supposed to be a class member.
8769 if (isa<CXXRecordDecl>(NewFD->getDeclContext()))
8770 NewFD->setAccess(AS_public);
8772 // Qualified decls generally require a previous declaration.
8773 if (D.getCXXScopeSpec().isSet()) {
8774 // ...with the major exception of templated-scope or
8775 // dependent-scope friend declarations.
8777 // TODO: we currently also suppress this check in dependent
8778 // contexts because (1) the parameter depth will be off when
8779 // matching friend templates and (2) we might actually be
8780 // selecting a friend based on a dependent factor. But there
8781 // are situations where these conditions don't apply and we
8782 // can actually do this check immediately.
8784 (TemplateParamLists.size() ||
8785 D.getCXXScopeSpec().getScopeRep()->isDependent() ||
8786 CurContext->isDependentContext())) {
8789 // The user tried to provide an out-of-line definition for a
8790 // function that is a member of a class or namespace, but there
8791 // was no such member function declared (C++ [class.mfct]p2,
8792 // C++ [namespace.memdef]p2). For example:
8798 // void X::f() { } // ill-formed
8800 // Complain about this problem, and attempt to suggest close
8801 // matches (e.g., those that differ only in cv-qualifiers and
8802 // whether the parameter types are references).
8804 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8805 *this, Previous, NewFD, ExtraArgs, false, nullptr)) {
8806 AddToScope = ExtraArgs.AddToScope;
8811 // Unqualified local friend declarations are required to resolve
8813 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) {
8814 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8815 *this, Previous, NewFD, ExtraArgs, true, S)) {
8816 AddToScope = ExtraArgs.AddToScope;
8820 } else if (!D.isFunctionDefinition() &&
8821 isa<CXXMethodDecl>(NewFD) && NewFD->isOutOfLine() &&
8822 !isFriend && !isFunctionTemplateSpecialization &&
8823 !isMemberSpecialization) {
8824 // An out-of-line member function declaration must also be a
8825 // definition (C++ [class.mfct]p2).
8826 // Note that this is not the case for explicit specializations of
8827 // function templates or member functions of class templates, per
8828 // C++ [temp.expl.spec]p2. We also allow these declarations as an
8829 // extension for compatibility with old SWIG code which likes to
8831 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration)
8832 << D.getCXXScopeSpec().getRange();
8836 ProcessPragmaWeak(S, NewFD);
8837 checkAttributesAfterMerging(*this, *NewFD);
8839 AddKnownFunctionAttributes(NewFD);
8841 if (NewFD->hasAttr<OverloadableAttr>() &&
8842 !NewFD->getType()->getAs<FunctionProtoType>()) {
8843 Diag(NewFD->getLocation(),
8844 diag::err_attribute_overloadable_no_prototype)
8847 // Turn this into a variadic function with no parameters.
8848 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>();
8849 FunctionProtoType::ExtProtoInfo EPI(
8850 Context.getDefaultCallingConvention(true, false));
8851 EPI.Variadic = true;
8852 EPI.ExtInfo = FT->getExtInfo();
8854 QualType R = Context.getFunctionType(FT->getReturnType(), None, EPI);
8858 // If there's a #pragma GCC visibility in scope, and this isn't a class
8859 // member, set the visibility of this function.
8860 if (!DC->isRecord() && NewFD->isExternallyVisible())
8861 AddPushedVisibilityAttribute(NewFD);
8863 // If there's a #pragma clang arc_cf_code_audited in scope, consider
8864 // marking the function.
8865 AddCFAuditedAttribute(NewFD);
8867 // If this is a function definition, check if we have to apply optnone due to
8869 if(D.isFunctionDefinition())
8870 AddRangeBasedOptnone(NewFD);
8872 // If this is the first declaration of an extern C variable, update
8873 // the map of such variables.
8874 if (NewFD->isFirstDecl() && !NewFD->isInvalidDecl() &&
8875 isIncompleteDeclExternC(*this, NewFD))
8876 RegisterLocallyScopedExternCDecl(NewFD, S);
8878 // Set this FunctionDecl's range up to the right paren.
8879 NewFD->setRangeEnd(D.getSourceRange().getEnd());
8881 if (D.isRedeclaration() && !Previous.empty()) {
8882 checkDLLAttributeRedeclaration(
8883 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewFD,
8884 isMemberSpecialization || isFunctionTemplateSpecialization,
8885 D.isFunctionDefinition());
8888 if (getLangOpts().CUDA) {
8889 IdentifierInfo *II = NewFD->getIdentifier();
8890 if (II && II->isStr("cudaConfigureCall") && !NewFD->isInvalidDecl() &&
8891 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
8892 if (!R->getAs<FunctionType>()->getReturnType()->isScalarType())
8893 Diag(NewFD->getLocation(), diag::err_config_scalar_return);
8895 Context.setcudaConfigureCallDecl(NewFD);
8898 // Variadic functions, other than a *declaration* of printf, are not allowed
8899 // in device-side CUDA code, unless someone passed
8900 // -fcuda-allow-variadic-functions.
8901 if (!getLangOpts().CUDAAllowVariadicFunctions && NewFD->isVariadic() &&
8902 (NewFD->hasAttr<CUDADeviceAttr>() ||
8903 NewFD->hasAttr<CUDAGlobalAttr>()) &&
8904 !(II && II->isStr("printf") && NewFD->isExternC() &&
8905 !D.isFunctionDefinition())) {
8906 Diag(NewFD->getLocation(), diag::err_variadic_device_fn);
8910 if (getLangOpts().CPlusPlus) {
8911 if (FunctionTemplate) {
8912 if (NewFD->isInvalidDecl())
8913 FunctionTemplate->setInvalidDecl();
8914 return FunctionTemplate;
8918 if (NewFD->hasAttr<OpenCLKernelAttr>()) {
8919 // OpenCL v1.2 s6.8 static is invalid for kernel functions.
8920 if ((getLangOpts().OpenCLVersion >= 120)
8921 && (SC == SC_Static)) {
8922 Diag(D.getIdentifierLoc(), diag::err_static_kernel);
8926 // OpenCL v1.2, s6.9 -- Kernels can only have return type void.
8927 if (!NewFD->getReturnType()->isVoidType()) {
8928 SourceRange RTRange = NewFD->getReturnTypeSourceRange();
8929 Diag(D.getIdentifierLoc(), diag::err_expected_kernel_void_return_type)
8930 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "void")
8935 llvm::SmallPtrSet<const Type *, 16> ValidTypes;
8936 for (auto Param : NewFD->parameters())
8937 checkIsValidOpenCLKernelParameter(*this, D, Param, ValidTypes);
8939 for (const ParmVarDecl *Param : NewFD->parameters()) {
8940 QualType PT = Param->getType();
8942 // OpenCL 2.0 pipe restrictions forbids pipe packet types to be non-value
8944 if (getLangOpts().OpenCLVersion >= 200) {
8945 if(const PipeType *PipeTy = PT->getAs<PipeType>()) {
8946 QualType ElemTy = PipeTy->getElementType();
8947 if (ElemTy->isReferenceType() || ElemTy->isPointerType()) {
8948 Diag(Param->getTypeSpecStartLoc(), diag::err_reference_pipe_type );
8955 MarkUnusedFileScopedDecl(NewFD);
8957 // Here we have an function template explicit specialization at class scope.
8958 // The actually specialization will be postponed to template instatiation
8959 // time via the ClassScopeFunctionSpecializationDecl node.
8960 if (isDependentClassScopeExplicitSpecialization) {
8961 ClassScopeFunctionSpecializationDecl *NewSpec =
8962 ClassScopeFunctionSpecializationDecl::Create(
8963 Context, CurContext, SourceLocation(),
8964 cast<CXXMethodDecl>(NewFD),
8965 HasExplicitTemplateArgs, TemplateArgs);
8966 CurContext->addDecl(NewSpec);
8973 /// \brief Checks if the new declaration declared in dependent context must be
8974 /// put in the same redeclaration chain as the specified declaration.
8976 /// \param D Declaration that is checked.
8977 /// \param PrevDecl Previous declaration found with proper lookup method for the
8978 /// same declaration name.
8979 /// \returns True if D must be added to the redeclaration chain which PrevDecl
8982 bool Sema::shouldLinkDependentDeclWithPrevious(Decl *D, Decl *PrevDecl) {
8983 // Any declarations should be put into redeclaration chains except for
8984 // friend declaration in a dependent context that names a function in
8987 // This allows to compile code like:
8990 // template<typename T> class C1 { friend void func() { } };
8991 // template<typename T> class C2 { friend void func() { } };
8993 // This code snippet is a valid code unless both templates are instantiated.
8994 return !(D->getLexicalDeclContext()->isDependentContext() &&
8995 D->getDeclContext()->isFileContext() &&
8996 D->getFriendObjectKind() != Decl::FOK_None);
8999 /// \brief Perform semantic checking of a new function declaration.
9001 /// Performs semantic analysis of the new function declaration
9002 /// NewFD. This routine performs all semantic checking that does not
9003 /// require the actual declarator involved in the declaration, and is
9004 /// used both for the declaration of functions as they are parsed
9005 /// (called via ActOnDeclarator) and for the declaration of functions
9006 /// that have been instantiated via C++ template instantiation (called
9007 /// via InstantiateDecl).
9009 /// \param IsMemberSpecialization whether this new function declaration is
9010 /// a member specialization (that replaces any definition provided by the
9011 /// previous declaration).
9013 /// This sets NewFD->isInvalidDecl() to true if there was an error.
9015 /// \returns true if the function declaration is a redeclaration.
9016 bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
9017 LookupResult &Previous,
9018 bool IsMemberSpecialization) {
9019 assert(!NewFD->getReturnType()->isVariablyModifiedType() &&
9020 "Variably modified return types are not handled here");
9022 // Determine whether the type of this function should be merged with
9023 // a previous visible declaration. This never happens for functions in C++,
9024 // and always happens in C if the previous declaration was visible.
9025 bool MergeTypeWithPrevious = !getLangOpts().CPlusPlus &&
9026 !Previous.isShadowed();
9028 bool Redeclaration = false;
9029 NamedDecl *OldDecl = nullptr;
9031 // Merge or overload the declaration with an existing declaration of
9032 // the same name, if appropriate.
9033 if (!Previous.empty()) {
9034 // Determine whether NewFD is an overload of PrevDecl or
9035 // a declaration that requires merging. If it's an overload,
9036 // there's no more work to do here; we'll just add the new
9037 // function to the scope.
9038 if (!AllowOverloadingOfFunction(Previous, Context)) {
9039 NamedDecl *Candidate = Previous.getRepresentativeDecl();
9040 if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) {
9041 Redeclaration = true;
9042 OldDecl = Candidate;
9045 switch (CheckOverload(S, NewFD, Previous, OldDecl,
9046 /*NewIsUsingDecl*/ false)) {
9048 Redeclaration = true;
9051 case Ovl_NonFunction:
9052 Redeclaration = true;
9056 Redeclaration = false;
9060 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
9061 // If a function name is overloadable in C, then every function
9062 // with that name must be marked "overloadable".
9063 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
9064 << Redeclaration << NewFD;
9065 NamedDecl *OverloadedDecl =
9066 Redeclaration ? OldDecl : Previous.getRepresentativeDecl();
9067 Diag(OverloadedDecl->getLocation(),
9068 diag::note_attribute_overloadable_prev_overload);
9069 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
9074 // Check for a previous extern "C" declaration with this name.
9075 if (!Redeclaration &&
9076 checkForConflictWithNonVisibleExternC(*this, NewFD, Previous)) {
9077 if (!Previous.empty()) {
9078 // This is an extern "C" declaration with the same name as a previous
9079 // declaration, and thus redeclares that entity...
9080 Redeclaration = true;
9081 OldDecl = Previous.getFoundDecl();
9082 MergeTypeWithPrevious = false;
9084 // ... except in the presence of __attribute__((overloadable)).
9085 if (OldDecl->hasAttr<OverloadableAttr>()) {
9086 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
9087 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
9088 << Redeclaration << NewFD;
9089 Diag(Previous.getFoundDecl()->getLocation(),
9090 diag::note_attribute_overloadable_prev_overload);
9091 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
9093 if (IsOverload(NewFD, cast<FunctionDecl>(OldDecl), false)) {
9094 Redeclaration = false;
9101 // C++11 [dcl.constexpr]p8:
9102 // A constexpr specifier for a non-static member function that is not
9103 // a constructor declares that member function to be const.
9105 // This needs to be delayed until we know whether this is an out-of-line
9106 // definition of a static member function.
9108 // This rule is not present in C++1y, so we produce a backwards
9109 // compatibility warning whenever it happens in C++11.
9110 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
9111 if (!getLangOpts().CPlusPlus14 && MD && MD->isConstexpr() &&
9112 !MD->isStatic() && !isa<CXXConstructorDecl>(MD) &&
9113 (MD->getTypeQualifiers() & Qualifiers::Const) == 0) {
9114 CXXMethodDecl *OldMD = nullptr;
9116 OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl->getAsFunction());
9117 if (!OldMD || !OldMD->isStatic()) {
9118 const FunctionProtoType *FPT =
9119 MD->getType()->castAs<FunctionProtoType>();
9120 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
9121 EPI.TypeQuals |= Qualifiers::Const;
9122 MD->setType(Context.getFunctionType(FPT->getReturnType(),
9123 FPT->getParamTypes(), EPI));
9125 // Warn that we did this, if we're not performing template instantiation.
9126 // In that case, we'll have warned already when the template was defined.
9127 if (!inTemplateInstantiation()) {
9128 SourceLocation AddConstLoc;
9129 if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
9130 .IgnoreParens().getAs<FunctionTypeLoc>())
9131 AddConstLoc = getLocForEndOfToken(FTL.getRParenLoc());
9133 Diag(MD->getLocation(), diag::warn_cxx14_compat_constexpr_not_const)
9134 << FixItHint::CreateInsertion(AddConstLoc, " const");
9139 if (Redeclaration) {
9140 // NewFD and OldDecl represent declarations that need to be
9142 if (MergeFunctionDecl(NewFD, OldDecl, S, MergeTypeWithPrevious)) {
9143 NewFD->setInvalidDecl();
9144 return Redeclaration;
9148 Previous.addDecl(OldDecl);
9150 if (FunctionTemplateDecl *OldTemplateDecl
9151 = dyn_cast<FunctionTemplateDecl>(OldDecl)) {
9152 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl());
9153 FunctionTemplateDecl *NewTemplateDecl
9154 = NewFD->getDescribedFunctionTemplate();
9155 assert(NewTemplateDecl && "Template/non-template mismatch");
9156 if (CXXMethodDecl *Method
9157 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) {
9158 Method->setAccess(OldTemplateDecl->getAccess());
9159 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess());
9162 // If this is an explicit specialization of a member that is a function
9163 // template, mark it as a member specialization.
9164 if (IsMemberSpecialization &&
9165 NewTemplateDecl->getInstantiatedFromMemberTemplate()) {
9166 NewTemplateDecl->setMemberSpecialization();
9167 assert(OldTemplateDecl->isMemberSpecialization());
9168 // Explicit specializations of a member template do not inherit deleted
9169 // status from the parent member template that they are specializing.
9170 if (OldTemplateDecl->getTemplatedDecl()->isDeleted()) {
9171 FunctionDecl *const OldTemplatedDecl =
9172 OldTemplateDecl->getTemplatedDecl();
9173 assert(OldTemplatedDecl->getCanonicalDecl() == OldTemplatedDecl);
9174 OldTemplatedDecl->setDeletedAsWritten(false);
9179 if (shouldLinkDependentDeclWithPrevious(NewFD, OldDecl)) {
9180 // This needs to happen first so that 'inline' propagates.
9181 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl));
9182 if (isa<CXXMethodDecl>(NewFD))
9183 NewFD->setAccess(OldDecl->getAccess());
9188 // Semantic checking for this function declaration (in isolation).
9190 if (getLangOpts().CPlusPlus) {
9191 // C++-specific checks.
9192 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) {
9193 CheckConstructor(Constructor);
9194 } else if (CXXDestructorDecl *Destructor =
9195 dyn_cast<CXXDestructorDecl>(NewFD)) {
9196 CXXRecordDecl *Record = Destructor->getParent();
9197 QualType ClassType = Context.getTypeDeclType(Record);
9199 // FIXME: Shouldn't we be able to perform this check even when the class
9200 // type is dependent? Both gcc and edg can handle that.
9201 if (!ClassType->isDependentType()) {
9202 DeclarationName Name
9203 = Context.DeclarationNames.getCXXDestructorName(
9204 Context.getCanonicalType(ClassType));
9205 if (NewFD->getDeclName() != Name) {
9206 Diag(NewFD->getLocation(), diag::err_destructor_name);
9207 NewFD->setInvalidDecl();
9208 return Redeclaration;
9211 } else if (CXXConversionDecl *Conversion
9212 = dyn_cast<CXXConversionDecl>(NewFD)) {
9213 ActOnConversionDeclarator(Conversion);
9214 } else if (auto *Guide = dyn_cast<CXXDeductionGuideDecl>(NewFD)) {
9215 if (auto *TD = Guide->getDescribedFunctionTemplate())
9216 CheckDeductionGuideTemplate(TD);
9218 // A deduction guide is not on the list of entities that can be
9219 // explicitly specialized.
9220 if (Guide->getTemplateSpecializationKind() == TSK_ExplicitSpecialization)
9221 Diag(Guide->getLocStart(), diag::err_deduction_guide_specialized)
9222 << /*explicit specialization*/ 1;
9225 // Find any virtual functions that this function overrides.
9226 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) {
9227 if (!Method->isFunctionTemplateSpecialization() &&
9228 !Method->getDescribedFunctionTemplate() &&
9229 Method->isCanonicalDecl()) {
9230 if (AddOverriddenMethods(Method->getParent(), Method)) {
9231 // If the function was marked as "static", we have a problem.
9232 if (NewFD->getStorageClass() == SC_Static) {
9233 ReportOverrides(*this, diag::err_static_overrides_virtual, Method);
9238 if (Method->isStatic())
9239 checkThisInStaticMemberFunctionType(Method);
9242 // Extra checking for C++ overloaded operators (C++ [over.oper]).
9243 if (NewFD->isOverloadedOperator() &&
9244 CheckOverloadedOperatorDeclaration(NewFD)) {
9245 NewFD->setInvalidDecl();
9246 return Redeclaration;
9249 // Extra checking for C++0x literal operators (C++0x [over.literal]).
9250 if (NewFD->getLiteralIdentifier() &&
9251 CheckLiteralOperatorDeclaration(NewFD)) {
9252 NewFD->setInvalidDecl();
9253 return Redeclaration;
9256 // In C++, check default arguments now that we have merged decls. Unless
9257 // the lexical context is the class, because in this case this is done
9258 // during delayed parsing anyway.
9259 if (!CurContext->isRecord())
9260 CheckCXXDefaultArguments(NewFD);
9262 // If this function declares a builtin function, check the type of this
9263 // declaration against the expected type for the builtin.
9264 if (unsigned BuiltinID = NewFD->getBuiltinID()) {
9265 ASTContext::GetBuiltinTypeError Error;
9266 LookupPredefedObjCSuperType(*this, S, NewFD->getIdentifier());
9267 QualType T = Context.GetBuiltinType(BuiltinID, Error);
9268 // If the type of the builtin differs only in its exception
9269 // specification, that's OK.
9270 // FIXME: If the types do differ in this way, it would be better to
9271 // retain the 'noexcept' form of the type.
9273 !Context.hasSameFunctionTypeIgnoringExceptionSpec(T,
9275 // The type of this function differs from the type of the builtin,
9276 // so forget about the builtin entirely.
9277 Context.BuiltinInfo.forgetBuiltin(BuiltinID, Context.Idents);
9280 // If this function is declared as being extern "C", then check to see if
9281 // the function returns a UDT (class, struct, or union type) that is not C
9282 // compatible, and if it does, warn the user.
9283 // But, issue any diagnostic on the first declaration only.
9284 if (Previous.empty() && NewFD->isExternC()) {
9285 QualType R = NewFD->getReturnType();
9286 if (R->isIncompleteType() && !R->isVoidType())
9287 Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete)
9289 else if (!R.isPODType(Context) && !R->isVoidType() &&
9290 !R->isObjCObjectPointerType())
9291 Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R;
9294 // C++1z [dcl.fct]p6:
9295 // [...] whether the function has a non-throwing exception-specification
9296 // [is] part of the function type
9298 // This results in an ABI break between C++14 and C++17 for functions whose
9299 // declared type includes an exception-specification in a parameter or
9300 // return type. (Exception specifications on the function itself are OK in
9301 // most cases, and exception specifications are not permitted in most other
9302 // contexts where they could make it into a mangling.)
9303 if (!getLangOpts().CPlusPlus1z && !NewFD->getPrimaryTemplate()) {
9304 auto HasNoexcept = [&](QualType T) -> bool {
9305 // Strip off declarator chunks that could be between us and a function
9306 // type. We don't need to look far, exception specifications are very
9307 // restricted prior to C++17.
9308 if (auto *RT = T->getAs<ReferenceType>())
9309 T = RT->getPointeeType();
9310 else if (T->isAnyPointerType())
9311 T = T->getPointeeType();
9312 else if (auto *MPT = T->getAs<MemberPointerType>())
9313 T = MPT->getPointeeType();
9314 if (auto *FPT = T->getAs<FunctionProtoType>())
9315 if (FPT->isNothrow(Context))
9320 auto *FPT = NewFD->getType()->castAs<FunctionProtoType>();
9321 bool AnyNoexcept = HasNoexcept(FPT->getReturnType());
9322 for (QualType T : FPT->param_types())
9323 AnyNoexcept |= HasNoexcept(T);
9325 Diag(NewFD->getLocation(),
9326 diag::warn_cxx1z_compat_exception_spec_in_signature)
9330 if (!Redeclaration && LangOpts.CUDA)
9331 checkCUDATargetOverload(NewFD, Previous);
9333 return Redeclaration;
9336 void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) {
9337 // C++11 [basic.start.main]p3:
9338 // A program that [...] declares main to be inline, static or
9339 // constexpr is ill-formed.
9340 // C11 6.7.4p4: In a hosted environment, no function specifier(s) shall
9341 // appear in a declaration of main.
9342 // static main is not an error under C99, but we should warn about it.
9343 // We accept _Noreturn main as an extension.
9344 if (FD->getStorageClass() == SC_Static)
9345 Diag(DS.getStorageClassSpecLoc(), getLangOpts().CPlusPlus
9346 ? diag::err_static_main : diag::warn_static_main)
9347 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
9348 if (FD->isInlineSpecified())
9349 Diag(DS.getInlineSpecLoc(), diag::err_inline_main)
9350 << FixItHint::CreateRemoval(DS.getInlineSpecLoc());
9351 if (DS.isNoreturnSpecified()) {
9352 SourceLocation NoreturnLoc = DS.getNoreturnSpecLoc();
9353 SourceRange NoreturnRange(NoreturnLoc, getLocForEndOfToken(NoreturnLoc));
9354 Diag(NoreturnLoc, diag::ext_noreturn_main);
9355 Diag(NoreturnLoc, diag::note_main_remove_noreturn)
9356 << FixItHint::CreateRemoval(NoreturnRange);
9358 if (FD->isConstexpr()) {
9359 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_main)
9360 << FixItHint::CreateRemoval(DS.getConstexprSpecLoc());
9361 FD->setConstexpr(false);
9364 if (getLangOpts().OpenCL) {
9365 Diag(FD->getLocation(), diag::err_opencl_no_main)
9366 << FD->hasAttr<OpenCLKernelAttr>();
9367 FD->setInvalidDecl();
9371 QualType T = FD->getType();
9372 assert(T->isFunctionType() && "function decl is not of function type");
9373 const FunctionType* FT = T->castAs<FunctionType>();
9375 if (getLangOpts().GNUMode && !getLangOpts().CPlusPlus) {
9376 // In C with GNU extensions we allow main() to have non-integer return
9377 // type, but we should warn about the extension, and we disable the
9378 // implicit-return-zero rule.
9380 // GCC in C mode accepts qualified 'int'.
9381 if (Context.hasSameUnqualifiedType(FT->getReturnType(), Context.IntTy))
9382 FD->setHasImplicitReturnZero(true);
9384 Diag(FD->getTypeSpecStartLoc(), diag::ext_main_returns_nonint);
9385 SourceRange RTRange = FD->getReturnTypeSourceRange();
9386 if (RTRange.isValid())
9387 Diag(RTRange.getBegin(), diag::note_main_change_return_type)
9388 << FixItHint::CreateReplacement(RTRange, "int");
9391 // In C and C++, main magically returns 0 if you fall off the end;
9392 // set the flag which tells us that.
9393 // This is C++ [basic.start.main]p5 and C99 5.1.2.2.3.
9395 // All the standards say that main() should return 'int'.
9396 if (Context.hasSameType(FT->getReturnType(), Context.IntTy))
9397 FD->setHasImplicitReturnZero(true);
9399 // Otherwise, this is just a flat-out error.
9400 SourceRange RTRange = FD->getReturnTypeSourceRange();
9401 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint)
9402 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "int")
9404 FD->setInvalidDecl(true);
9408 // Treat protoless main() as nullary.
9409 if (isa<FunctionNoProtoType>(FT)) return;
9411 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT);
9412 unsigned nparams = FTP->getNumParams();
9413 assert(FD->getNumParams() == nparams);
9415 bool HasExtraParameters = (nparams > 3);
9417 if (FTP->isVariadic()) {
9418 Diag(FD->getLocation(), diag::ext_variadic_main);
9419 // FIXME: if we had information about the location of the ellipsis, we
9420 // could add a FixIt hint to remove it as a parameter.
9423 // Darwin passes an undocumented fourth argument of type char**. If
9424 // other platforms start sprouting these, the logic below will start
9426 if (nparams == 4 && Context.getTargetInfo().getTriple().isOSDarwin())
9427 HasExtraParameters = false;
9429 if (HasExtraParameters) {
9430 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams;
9431 FD->setInvalidDecl(true);
9435 // FIXME: a lot of the following diagnostics would be improved
9436 // if we had some location information about types.
9439 Context.getPointerType(Context.getPointerType(Context.CharTy));
9440 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP };
9442 for (unsigned i = 0; i < nparams; ++i) {
9443 QualType AT = FTP->getParamType(i);
9445 bool mismatch = true;
9447 if (Context.hasSameUnqualifiedType(AT, Expected[i]))
9449 else if (Expected[i] == CharPP) {
9450 // As an extension, the following forms are okay:
9452 // char const * const *
9455 QualifierCollector qs;
9456 const PointerType* PT;
9457 if ((PT = qs.strip(AT)->getAs<PointerType>()) &&
9458 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) &&
9459 Context.hasSameType(QualType(qs.strip(PT->getPointeeType()), 0),
9462 mismatch = !qs.empty();
9467 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i];
9468 // TODO: suggest replacing given type with expected type
9469 FD->setInvalidDecl(true);
9473 if (nparams == 1 && !FD->isInvalidDecl()) {
9474 Diag(FD->getLocation(), diag::warn_main_one_arg);
9477 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
9478 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
9479 FD->setInvalidDecl();
9483 void Sema::CheckMSVCRTEntryPoint(FunctionDecl *FD) {
9484 QualType T = FD->getType();
9485 assert(T->isFunctionType() && "function decl is not of function type");
9486 const FunctionType *FT = T->castAs<FunctionType>();
9488 // Set an implicit return of 'zero' if the function can return some integral,
9489 // enumeration, pointer or nullptr type.
9490 if (FT->getReturnType()->isIntegralOrEnumerationType() ||
9491 FT->getReturnType()->isAnyPointerType() ||
9492 FT->getReturnType()->isNullPtrType())
9493 // DllMain is exempt because a return value of zero means it failed.
9494 if (FD->getName() != "DllMain")
9495 FD->setHasImplicitReturnZero(true);
9497 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
9498 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
9499 FD->setInvalidDecl();
9503 bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
9504 // FIXME: Need strict checking. In C89, we need to check for
9505 // any assignment, increment, decrement, function-calls, or
9506 // commas outside of a sizeof. In C99, it's the same list,
9507 // except that the aforementioned are allowed in unevaluated
9508 // expressions. Everything else falls under the
9509 // "may accept other forms of constant expressions" exception.
9510 // (We never end up here for C++, so the constant expression
9511 // rules there don't matter.)
9512 const Expr *Culprit;
9513 if (Init->isConstantInitializer(Context, false, &Culprit))
9515 Diag(Culprit->getExprLoc(), diag::err_init_element_not_constant)
9516 << Culprit->getSourceRange();
9521 // Visits an initialization expression to see if OrigDecl is evaluated in
9522 // its own initialization and throws a warning if it does.
9523 class SelfReferenceChecker
9524 : public EvaluatedExprVisitor<SelfReferenceChecker> {
9529 bool isReferenceType;
9532 llvm::SmallVector<unsigned, 4> InitFieldIndex;
9535 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited;
9537 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context),
9538 S(S), OrigDecl(OrigDecl) {
9540 isRecordType = false;
9541 isReferenceType = false;
9543 if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) {
9544 isPODType = VD->getType().isPODType(S.Context);
9545 isRecordType = VD->getType()->isRecordType();
9546 isReferenceType = VD->getType()->isReferenceType();
9550 // For most expressions, just call the visitor. For initializer lists,
9551 // track the index of the field being initialized since fields are
9552 // initialized in order allowing use of previously initialized fields.
9553 void CheckExpr(Expr *E) {
9554 InitListExpr *InitList = dyn_cast<InitListExpr>(E);
9560 // Track and increment the index here.
9562 InitFieldIndex.push_back(0);
9563 for (auto Child : InitList->children()) {
9564 CheckExpr(cast<Expr>(Child));
9565 ++InitFieldIndex.back();
9567 InitFieldIndex.pop_back();
9570 // Returns true if MemberExpr is checked and no further checking is needed.
9571 // Returns false if additional checking is required.
9572 bool CheckInitListMemberExpr(MemberExpr *E, bool CheckReference) {
9573 llvm::SmallVector<FieldDecl*, 4> Fields;
9575 bool ReferenceField = false;
9577 // Get the field memebers used.
9578 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9579 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
9582 Fields.push_back(FD);
9583 if (FD->getType()->isReferenceType())
9584 ReferenceField = true;
9585 Base = ME->getBase()->IgnoreParenImpCasts();
9588 // Keep checking only if the base Decl is the same.
9589 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base);
9590 if (!DRE || DRE->getDecl() != OrigDecl)
9593 // A reference field can be bound to an unininitialized field.
9594 if (CheckReference && !ReferenceField)
9597 // Convert FieldDecls to their index number.
9598 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
9599 for (const FieldDecl *I : llvm::reverse(Fields))
9600 UsedFieldIndex.push_back(I->getFieldIndex());
9602 // See if a warning is needed by checking the first difference in index
9603 // numbers. If field being used has index less than the field being
9604 // initialized, then the use is safe.
9605 for (auto UsedIter = UsedFieldIndex.begin(),
9606 UsedEnd = UsedFieldIndex.end(),
9607 OrigIter = InitFieldIndex.begin(),
9608 OrigEnd = InitFieldIndex.end();
9609 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
9610 if (*UsedIter < *OrigIter)
9612 if (*UsedIter > *OrigIter)
9616 // TODO: Add a different warning which will print the field names.
9617 HandleDeclRefExpr(DRE);
9621 // For most expressions, the cast is directly above the DeclRefExpr.
9622 // For conditional operators, the cast can be outside the conditional
9623 // operator if both expressions are DeclRefExpr's.
9624 void HandleValue(Expr *E) {
9625 E = E->IgnoreParens();
9626 if (DeclRefExpr* DRE = dyn_cast<DeclRefExpr>(E)) {
9627 HandleDeclRefExpr(DRE);
9631 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
9632 Visit(CO->getCond());
9633 HandleValue(CO->getTrueExpr());
9634 HandleValue(CO->getFalseExpr());
9638 if (BinaryConditionalOperator *BCO =
9639 dyn_cast<BinaryConditionalOperator>(E)) {
9640 Visit(BCO->getCond());
9641 HandleValue(BCO->getFalseExpr());
9645 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
9646 HandleValue(OVE->getSourceExpr());
9650 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
9651 if (BO->getOpcode() == BO_Comma) {
9652 Visit(BO->getLHS());
9653 HandleValue(BO->getRHS());
9658 if (isa<MemberExpr>(E)) {
9660 if (CheckInitListMemberExpr(cast<MemberExpr>(E),
9661 false /*CheckReference*/))
9665 Expr *Base = E->IgnoreParenImpCasts();
9666 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9667 // Check for static member variables and don't warn on them.
9668 if (!isa<FieldDecl>(ME->getMemberDecl()))
9670 Base = ME->getBase()->IgnoreParenImpCasts();
9672 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base))
9673 HandleDeclRefExpr(DRE);
9680 // Reference types not handled in HandleValue are handled here since all
9681 // uses of references are bad, not just r-value uses.
9682 void VisitDeclRefExpr(DeclRefExpr *E) {
9683 if (isReferenceType)
9684 HandleDeclRefExpr(E);
9687 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
9688 if (E->getCastKind() == CK_LValueToRValue) {
9689 HandleValue(E->getSubExpr());
9693 Inherited::VisitImplicitCastExpr(E);
9696 void VisitMemberExpr(MemberExpr *E) {
9698 if (CheckInitListMemberExpr(E, true /*CheckReference*/))
9702 // Don't warn on arrays since they can be treated as pointers.
9703 if (E->getType()->canDecayToPointerType()) return;
9705 // Warn when a non-static method call is followed by non-static member
9706 // field accesses, which is followed by a DeclRefExpr.
9707 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl());
9708 bool Warn = (MD && !MD->isStatic());
9709 Expr *Base = E->getBase()->IgnoreParenImpCasts();
9710 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9711 if (!isa<FieldDecl>(ME->getMemberDecl()))
9713 Base = ME->getBase()->IgnoreParenImpCasts();
9716 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
9718 HandleDeclRefExpr(DRE);
9722 // The base of a MemberExpr is not a MemberExpr or a DeclRefExpr.
9723 // Visit that expression.
9727 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
9728 Expr *Callee = E->getCallee();
9730 if (isa<UnresolvedLookupExpr>(Callee))
9731 return Inherited::VisitCXXOperatorCallExpr(E);
9734 for (auto Arg: E->arguments())
9735 HandleValue(Arg->IgnoreParenImpCasts());
9738 void VisitUnaryOperator(UnaryOperator *E) {
9739 // For POD record types, addresses of its own members are well-defined.
9740 if (E->getOpcode() == UO_AddrOf && isRecordType &&
9741 isa<MemberExpr>(E->getSubExpr()->IgnoreParens())) {
9743 HandleValue(E->getSubExpr());
9747 if (E->isIncrementDecrementOp()) {
9748 HandleValue(E->getSubExpr());
9752 Inherited::VisitUnaryOperator(E);
9755 void VisitObjCMessageExpr(ObjCMessageExpr *E) {}
9757 void VisitCXXConstructExpr(CXXConstructExpr *E) {
9758 if (E->getConstructor()->isCopyConstructor()) {
9759 Expr *ArgExpr = E->getArg(0);
9760 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
9761 if (ILE->getNumInits() == 1)
9762 ArgExpr = ILE->getInit(0);
9763 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
9764 if (ICE->getCastKind() == CK_NoOp)
9765 ArgExpr = ICE->getSubExpr();
9766 HandleValue(ArgExpr);
9769 Inherited::VisitCXXConstructExpr(E);
9772 void VisitCallExpr(CallExpr *E) {
9773 // Treat std::move as a use.
9774 if (E->getNumArgs() == 1) {
9775 if (FunctionDecl *FD = E->getDirectCallee()) {
9776 if (FD->isInStdNamespace() && FD->getIdentifier() &&
9777 FD->getIdentifier()->isStr("move")) {
9778 HandleValue(E->getArg(0));
9784 Inherited::VisitCallExpr(E);
9787 void VisitBinaryOperator(BinaryOperator *E) {
9788 if (E->isCompoundAssignmentOp()) {
9789 HandleValue(E->getLHS());
9794 Inherited::VisitBinaryOperator(E);
9797 // A custom visitor for BinaryConditionalOperator is needed because the
9798 // regular visitor would check the condition and true expression separately
9799 // but both point to the same place giving duplicate diagnostics.
9800 void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
9801 Visit(E->getCond());
9802 Visit(E->getFalseExpr());
9805 void HandleDeclRefExpr(DeclRefExpr *DRE) {
9806 Decl* ReferenceDecl = DRE->getDecl();
9807 if (OrigDecl != ReferenceDecl) return;
9809 if (isReferenceType) {
9810 diag = diag::warn_uninit_self_reference_in_reference_init;
9811 } else if (cast<VarDecl>(OrigDecl)->isStaticLocal()) {
9812 diag = diag::warn_static_self_reference_in_init;
9813 } else if (isa<TranslationUnitDecl>(OrigDecl->getDeclContext()) ||
9814 isa<NamespaceDecl>(OrigDecl->getDeclContext()) ||
9815 DRE->getDecl()->getType()->isRecordType()) {
9816 diag = diag::warn_uninit_self_reference_in_init;
9818 // Local variables will be handled by the CFG analysis.
9822 S.DiagRuntimeBehavior(DRE->getLocStart(), DRE,
9824 << DRE->getNameInfo().getName()
9825 << OrigDecl->getLocation()
9826 << DRE->getSourceRange());
9830 /// CheckSelfReference - Warns if OrigDecl is used in expression E.
9831 static void CheckSelfReference(Sema &S, Decl* OrigDecl, Expr *E,
9833 // Parameters arguments are occassionially constructed with itself,
9834 // for instance, in recursive functions. Skip them.
9835 if (isa<ParmVarDecl>(OrigDecl))
9838 E = E->IgnoreParens();
9840 // Skip checking T a = a where T is not a record or reference type.
9841 // Doing so is a way to silence uninitialized warnings.
9842 if (!DirectInit && !cast<VarDecl>(OrigDecl)->getType()->isRecordType())
9843 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
9844 if (ICE->getCastKind() == CK_LValueToRValue)
9845 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()))
9846 if (DRE->getDecl() == OrigDecl)
9849 SelfReferenceChecker(S, OrigDecl).CheckExpr(E);
9851 } // end anonymous namespace
9854 // Simple wrapper to add the name of a variable or (if no variable is
9855 // available) a DeclarationName into a diagnostic.
9856 struct VarDeclOrName {
9858 DeclarationName Name;
9860 friend const Sema::SemaDiagnosticBuilder &
9861 operator<<(const Sema::SemaDiagnosticBuilder &Diag, VarDeclOrName VN) {
9862 return VN.VDecl ? Diag << VN.VDecl : Diag << VN.Name;
9865 } // end anonymous namespace
9867 QualType Sema::deduceVarTypeFromInitializer(VarDecl *VDecl,
9868 DeclarationName Name, QualType Type,
9869 TypeSourceInfo *TSI,
9870 SourceRange Range, bool DirectInit,
9872 bool IsInitCapture = !VDecl;
9873 assert((!VDecl || !VDecl->isInitCapture()) &&
9874 "init captures are expected to be deduced prior to initialization");
9876 VarDeclOrName VN{VDecl, Name};
9878 DeducedType *Deduced = Type->getContainedDeducedType();
9879 assert(Deduced && "deduceVarTypeFromInitializer for non-deduced type");
9881 // C++11 [dcl.spec.auto]p3
9883 assert(VDecl && "no init for init capture deduction?");
9884 Diag(VDecl->getLocation(), diag::err_auto_var_requires_init)
9885 << VDecl->getDeclName() << Type;
9889 ArrayRef<Expr*> DeduceInits = Init;
9891 if (auto *PL = dyn_cast_or_null<ParenListExpr>(Init))
9892 DeduceInits = PL->exprs();
9895 if (isa<DeducedTemplateSpecializationType>(Deduced)) {
9896 assert(VDecl && "non-auto type for init capture deduction?");
9897 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
9898 InitializationKind Kind = InitializationKind::CreateForInit(
9899 VDecl->getLocation(), DirectInit, Init);
9900 // FIXME: Initialization should not be taking a mutable list of inits.
9901 SmallVector<Expr*, 8> InitsCopy(DeduceInits.begin(), DeduceInits.end());
9902 return DeduceTemplateSpecializationFromInitializer(TSI, Entity, Kind,
9907 if (auto *IL = dyn_cast<InitListExpr>(Init))
9908 DeduceInits = IL->inits();
9911 // Deduction only works if we have exactly one source expression.
9912 if (DeduceInits.empty()) {
9913 // It isn't possible to write this directly, but it is possible to
9914 // end up in this situation with "auto x(some_pack...);"
9915 Diag(Init->getLocStart(), IsInitCapture
9916 ? diag::err_init_capture_no_expression
9917 : diag::err_auto_var_init_no_expression)
9918 << VN << Type << Range;
9922 if (DeduceInits.size() > 1) {
9923 Diag(DeduceInits[1]->getLocStart(),
9924 IsInitCapture ? diag::err_init_capture_multiple_expressions
9925 : diag::err_auto_var_init_multiple_expressions)
9926 << VN << Type << Range;
9930 Expr *DeduceInit = DeduceInits[0];
9931 if (DirectInit && isa<InitListExpr>(DeduceInit)) {
9932 Diag(Init->getLocStart(), IsInitCapture
9933 ? diag::err_init_capture_paren_braces
9934 : diag::err_auto_var_init_paren_braces)
9935 << isa<InitListExpr>(Init) << VN << Type << Range;
9939 // Expressions default to 'id' when we're in a debugger.
9940 bool DefaultedAnyToId = false;
9941 if (getLangOpts().DebuggerCastResultToId &&
9942 Init->getType() == Context.UnknownAnyTy && !IsInitCapture) {
9943 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
9944 if (Result.isInvalid()) {
9947 Init = Result.get();
9948 DefaultedAnyToId = true;
9951 // C++ [dcl.decomp]p1:
9952 // If the assignment-expression [...] has array type A and no ref-qualifier
9953 // is present, e has type cv A
9954 if (VDecl && isa<DecompositionDecl>(VDecl) &&
9955 Context.hasSameUnqualifiedType(Type, Context.getAutoDeductType()) &&
9956 DeduceInit->getType()->isConstantArrayType())
9957 return Context.getQualifiedType(DeduceInit->getType(),
9958 Type.getQualifiers());
9960 QualType DeducedType;
9961 if (DeduceAutoType(TSI, DeduceInit, DeducedType) == DAR_Failed) {
9963 DiagnoseAutoDeductionFailure(VDecl, DeduceInit);
9964 else if (isa<InitListExpr>(Init))
9965 Diag(Range.getBegin(),
9966 diag::err_init_capture_deduction_failure_from_init_list)
9968 << (DeduceInit->getType().isNull() ? TSI->getType()
9969 : DeduceInit->getType())
9970 << DeduceInit->getSourceRange();
9972 Diag(Range.getBegin(), diag::err_init_capture_deduction_failure)
9973 << VN << TSI->getType()
9974 << (DeduceInit->getType().isNull() ? TSI->getType()
9975 : DeduceInit->getType())
9976 << DeduceInit->getSourceRange();
9979 // Warn if we deduced 'id'. 'auto' usually implies type-safety, but using
9980 // 'id' instead of a specific object type prevents most of our usual
9982 // We only want to warn outside of template instantiations, though:
9983 // inside a template, the 'id' could have come from a parameter.
9984 if (!inTemplateInstantiation() && !DefaultedAnyToId && !IsInitCapture &&
9985 !DeducedType.isNull() && DeducedType->isObjCIdType()) {
9986 SourceLocation Loc = TSI->getTypeLoc().getBeginLoc();
9987 Diag(Loc, diag::warn_auto_var_is_id) << VN << Range;
9993 bool Sema::DeduceVariableDeclarationType(VarDecl *VDecl, bool DirectInit,
9995 QualType DeducedType = deduceVarTypeFromInitializer(
9996 VDecl, VDecl->getDeclName(), VDecl->getType(), VDecl->getTypeSourceInfo(),
9997 VDecl->getSourceRange(), DirectInit, Init);
9998 if (DeducedType.isNull()) {
9999 VDecl->setInvalidDecl();
10003 VDecl->setType(DeducedType);
10004 assert(VDecl->isLinkageValid());
10006 // In ARC, infer lifetime.
10007 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(VDecl))
10008 VDecl->setInvalidDecl();
10010 // If this is a redeclaration, check that the type we just deduced matches
10011 // the previously declared type.
10012 if (VarDecl *Old = VDecl->getPreviousDecl()) {
10013 // We never need to merge the type, because we cannot form an incomplete
10014 // array of auto, nor deduce such a type.
10015 MergeVarDeclTypes(VDecl, Old, /*MergeTypeWithPrevious*/ false);
10018 // Check the deduced type is valid for a variable declaration.
10019 CheckVariableDeclarationType(VDecl);
10020 return VDecl->isInvalidDecl();
10023 /// AddInitializerToDecl - Adds the initializer Init to the
10024 /// declaration dcl. If DirectInit is true, this is C++ direct
10025 /// initialization rather than copy initialization.
10026 void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) {
10027 // If there is no declaration, there was an error parsing it. Just ignore
10028 // the initializer.
10029 if (!RealDecl || RealDecl->isInvalidDecl()) {
10030 CorrectDelayedTyposInExpr(Init, dyn_cast_or_null<VarDecl>(RealDecl));
10034 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) {
10035 // Pure-specifiers are handled in ActOnPureSpecifier.
10036 Diag(Method->getLocation(), diag::err_member_function_initialization)
10037 << Method->getDeclName() << Init->getSourceRange();
10038 Method->setInvalidDecl();
10042 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl);
10044 assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here");
10045 Diag(RealDecl->getLocation(), diag::err_illegal_initializer);
10046 RealDecl->setInvalidDecl();
10050 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for.
10051 if (VDecl->getType()->isUndeducedType()) {
10052 // Attempt typo correction early so that the type of the init expression can
10053 // be deduced based on the chosen correction if the original init contains a
10055 ExprResult Res = CorrectDelayedTyposInExpr(Init, VDecl);
10056 if (!Res.isUsable()) {
10057 RealDecl->setInvalidDecl();
10062 if (DeduceVariableDeclarationType(VDecl, DirectInit, Init))
10066 // dllimport cannot be used on variable definitions.
10067 if (VDecl->hasAttr<DLLImportAttr>() && !VDecl->isStaticDataMember()) {
10068 Diag(VDecl->getLocation(), diag::err_attribute_dllimport_data_definition);
10069 VDecl->setInvalidDecl();
10073 if (VDecl->isLocalVarDecl() && VDecl->hasExternalStorage()) {
10074 // C99 6.7.8p5. C++ has no such restriction, but that is a defect.
10075 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init);
10076 VDecl->setInvalidDecl();
10080 if (!VDecl->getType()->isDependentType()) {
10081 // A definition must end up with a complete type, which means it must be
10082 // complete with the restriction that an array type might be completed by
10083 // the initializer; note that later code assumes this restriction.
10084 QualType BaseDeclType = VDecl->getType();
10085 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType))
10086 BaseDeclType = Array->getElementType();
10087 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType,
10088 diag::err_typecheck_decl_incomplete_type)) {
10089 RealDecl->setInvalidDecl();
10093 // The variable can not have an abstract class type.
10094 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(),
10095 diag::err_abstract_type_in_decl,
10096 AbstractVariableType))
10097 VDecl->setInvalidDecl();
10100 // If adding the initializer will turn this declaration into a definition,
10101 // and we already have a definition for this variable, diagnose or otherwise
10102 // handle the situation.
10104 if ((Def = VDecl->getDefinition()) && Def != VDecl &&
10105 (!VDecl->isStaticDataMember() || VDecl->isOutOfLine()) &&
10106 !VDecl->isThisDeclarationADemotedDefinition() &&
10107 checkVarDeclRedefinition(Def, VDecl))
10110 if (getLangOpts().CPlusPlus) {
10111 // C++ [class.static.data]p4
10112 // If a static data member is of const integral or const
10113 // enumeration type, its declaration in the class definition can
10114 // specify a constant-initializer which shall be an integral
10115 // constant expression (5.19). In that case, the member can appear
10116 // in integral constant expressions. The member shall still be
10117 // defined in a namespace scope if it is used in the program and the
10118 // namespace scope definition shall not contain an initializer.
10120 // We already performed a redefinition check above, but for static
10121 // data members we also need to check whether there was an in-class
10122 // declaration with an initializer.
10123 if (VDecl->isStaticDataMember() && VDecl->getCanonicalDecl()->hasInit()) {
10124 Diag(Init->getExprLoc(), diag::err_static_data_member_reinitialization)
10125 << VDecl->getDeclName();
10126 Diag(VDecl->getCanonicalDecl()->getInit()->getExprLoc(),
10127 diag::note_previous_initializer)
10132 if (VDecl->hasLocalStorage())
10133 getCurFunction()->setHasBranchProtectedScope();
10135 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) {
10136 VDecl->setInvalidDecl();
10141 // OpenCL 1.1 6.5.2: "Variables allocated in the __local address space inside
10142 // a kernel function cannot be initialized."
10143 if (VDecl->getType().getAddressSpace() == LangAS::opencl_local) {
10144 Diag(VDecl->getLocation(), diag::err_local_cant_init);
10145 VDecl->setInvalidDecl();
10149 // Get the decls type and save a reference for later, since
10150 // CheckInitializerTypes may change it.
10151 QualType DclT = VDecl->getType(), SavT = DclT;
10153 // Expressions default to 'id' when we're in a debugger
10154 // and we are assigning it to a variable of Objective-C pointer type.
10155 if (getLangOpts().DebuggerCastResultToId && DclT->isObjCObjectPointerType() &&
10156 Init->getType() == Context.UnknownAnyTy) {
10157 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
10158 if (Result.isInvalid()) {
10159 VDecl->setInvalidDecl();
10162 Init = Result.get();
10165 // Perform the initialization.
10166 ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
10167 if (!VDecl->isInvalidDecl()) {
10168 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
10169 InitializationKind Kind = InitializationKind::CreateForInit(
10170 VDecl->getLocation(), DirectInit, Init);
10172 MultiExprArg Args = Init;
10174 Args = MultiExprArg(CXXDirectInit->getExprs(),
10175 CXXDirectInit->getNumExprs());
10177 // Try to correct any TypoExprs in the initialization arguments.
10178 for (size_t Idx = 0; Idx < Args.size(); ++Idx) {
10179 ExprResult Res = CorrectDelayedTyposInExpr(
10180 Args[Idx], VDecl, [this, Entity, Kind](Expr *E) {
10181 InitializationSequence Init(*this, Entity, Kind, MultiExprArg(E));
10182 return Init.Failed() ? ExprError() : E;
10184 if (Res.isInvalid()) {
10185 VDecl->setInvalidDecl();
10186 } else if (Res.get() != Args[Idx]) {
10187 Args[Idx] = Res.get();
10190 if (VDecl->isInvalidDecl())
10193 InitializationSequence InitSeq(*this, Entity, Kind, Args,
10194 /*TopLevelOfInitList=*/false,
10195 /*TreatUnavailableAsInvalid=*/false);
10196 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
10197 if (Result.isInvalid()) {
10198 VDecl->setInvalidDecl();
10202 Init = Result.getAs<Expr>();
10205 // Check for self-references within variable initializers.
10206 // Variables declared within a function/method body (except for references)
10207 // are handled by a dataflow analysis.
10208 if (!VDecl->hasLocalStorage() || VDecl->getType()->isRecordType() ||
10209 VDecl->getType()->isReferenceType()) {
10210 CheckSelfReference(*this, RealDecl, Init, DirectInit);
10213 // If the type changed, it means we had an incomplete type that was
10214 // completed by the initializer. For example:
10215 // int ary[] = { 1, 3, 5 };
10216 // "ary" transitions from an IncompleteArrayType to a ConstantArrayType.
10217 if (!VDecl->isInvalidDecl() && (DclT != SavT))
10218 VDecl->setType(DclT);
10220 if (!VDecl->isInvalidDecl()) {
10221 checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init);
10223 if (VDecl->hasAttr<BlocksAttr>())
10224 checkRetainCycles(VDecl, Init);
10226 // It is safe to assign a weak reference into a strong variable.
10227 // Although this code can still have problems:
10228 // id x = self.weakProp;
10229 // id y = self.weakProp;
10230 // we do not warn to warn spuriously when 'x' and 'y' are on separate
10231 // paths through the function. This should be revisited if
10232 // -Wrepeated-use-of-weak is made flow-sensitive.
10233 if ((VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong ||
10234 VDecl->getType().isNonWeakInMRRWithObjCWeak(Context)) &&
10235 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
10236 Init->getLocStart()))
10237 getCurFunction()->markSafeWeakUse(Init);
10240 // The initialization is usually a full-expression.
10242 // FIXME: If this is a braced initialization of an aggregate, it is not
10243 // an expression, and each individual field initializer is a separate
10244 // full-expression. For instance, in:
10246 // struct Temp { ~Temp(); };
10247 // struct S { S(Temp); };
10248 // struct T { S a, b; } t = { Temp(), Temp() }
10250 // we should destroy the first Temp before constructing the second.
10251 ExprResult Result = ActOnFinishFullExpr(Init, VDecl->getLocation(),
10253 VDecl->isConstexpr());
10254 if (Result.isInvalid()) {
10255 VDecl->setInvalidDecl();
10258 Init = Result.get();
10260 // Attach the initializer to the decl.
10261 VDecl->setInit(Init);
10263 if (VDecl->isLocalVarDecl()) {
10264 // C99 6.7.8p4: All the expressions in an initializer for an object that has
10265 // static storage duration shall be constant expressions or string literals.
10266 // C++ does not have this restriction.
10267 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl()) {
10268 const Expr *Culprit;
10269 if (VDecl->getStorageClass() == SC_Static)
10270 CheckForConstantInitializer(Init, DclT);
10271 // C89 is stricter than C99 for non-static aggregate types.
10272 // C89 6.5.7p3: All the expressions [...] in an initializer list
10273 // for an object that has aggregate or union type shall be
10274 // constant expressions.
10275 else if (!getLangOpts().C99 && VDecl->getType()->isAggregateType() &&
10276 isa<InitListExpr>(Init) &&
10277 !Init->isConstantInitializer(Context, false, &Culprit))
10278 Diag(Culprit->getExprLoc(),
10279 diag::ext_aggregate_init_not_constant)
10280 << Culprit->getSourceRange();
10282 } else if (VDecl->isStaticDataMember() && !VDecl->isInline() &&
10283 VDecl->getLexicalDeclContext()->isRecord()) {
10284 // This is an in-class initialization for a static data member, e.g.,
10287 // static const int value = 17;
10290 // C++ [class.mem]p4:
10291 // A member-declarator can contain a constant-initializer only
10292 // if it declares a static member (9.4) of const integral or
10293 // const enumeration type, see 9.4.2.
10295 // C++11 [class.static.data]p3:
10296 // If a non-volatile non-inline const static data member is of integral
10297 // or enumeration type, its declaration in the class definition can
10298 // specify a brace-or-equal-initializer in which every initializer-clause
10299 // that is an assignment-expression is a constant expression. A static
10300 // data member of literal type can be declared in the class definition
10301 // with the constexpr specifier; if so, its declaration shall specify a
10302 // brace-or-equal-initializer in which every initializer-clause that is
10303 // an assignment-expression is a constant expression.
10305 // Do nothing on dependent types.
10306 if (DclT->isDependentType()) {
10308 // Allow any 'static constexpr' members, whether or not they are of literal
10309 // type. We separately check that every constexpr variable is of literal
10311 } else if (VDecl->isConstexpr()) {
10313 // Require constness.
10314 } else if (!DclT.isConstQualified()) {
10315 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const)
10316 << Init->getSourceRange();
10317 VDecl->setInvalidDecl();
10319 // We allow integer constant expressions in all cases.
10320 } else if (DclT->isIntegralOrEnumerationType()) {
10321 // Check whether the expression is a constant expression.
10322 SourceLocation Loc;
10323 if (getLangOpts().CPlusPlus11 && DclT.isVolatileQualified())
10324 // In C++11, a non-constexpr const static data member with an
10325 // in-class initializer cannot be volatile.
10326 Diag(VDecl->getLocation(), diag::err_in_class_initializer_volatile);
10327 else if (Init->isValueDependent())
10328 ; // Nothing to check.
10329 else if (Init->isIntegerConstantExpr(Context, &Loc))
10330 ; // Ok, it's an ICE!
10331 else if (Init->isEvaluatable(Context)) {
10332 // If we can constant fold the initializer through heroics, accept it,
10333 // but report this as a use of an extension for -pedantic.
10334 Diag(Loc, diag::ext_in_class_initializer_non_constant)
10335 << Init->getSourceRange();
10337 // Otherwise, this is some crazy unknown case. Report the issue at the
10338 // location provided by the isIntegerConstantExpr failed check.
10339 Diag(Loc, diag::err_in_class_initializer_non_constant)
10340 << Init->getSourceRange();
10341 VDecl->setInvalidDecl();
10344 // We allow foldable floating-point constants as an extension.
10345 } else if (DclT->isFloatingType()) { // also permits complex, which is ok
10346 // In C++98, this is a GNU extension. In C++11, it is not, but we support
10347 // it anyway and provide a fixit to add the 'constexpr'.
10348 if (getLangOpts().CPlusPlus11) {
10349 Diag(VDecl->getLocation(),
10350 diag::ext_in_class_initializer_float_type_cxx11)
10351 << DclT << Init->getSourceRange();
10352 Diag(VDecl->getLocStart(),
10353 diag::note_in_class_initializer_float_type_cxx11)
10354 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
10356 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type)
10357 << DclT << Init->getSourceRange();
10359 if (!Init->isValueDependent() && !Init->isEvaluatable(Context)) {
10360 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant)
10361 << Init->getSourceRange();
10362 VDecl->setInvalidDecl();
10366 // Suggest adding 'constexpr' in C++11 for literal types.
10367 } else if (getLangOpts().CPlusPlus11 && DclT->isLiteralType(Context)) {
10368 Diag(VDecl->getLocation(), diag::err_in_class_initializer_literal_type)
10369 << DclT << Init->getSourceRange()
10370 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
10371 VDecl->setConstexpr(true);
10374 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type)
10375 << DclT << Init->getSourceRange();
10376 VDecl->setInvalidDecl();
10378 } else if (VDecl->isFileVarDecl()) {
10379 // In C, extern is typically used to avoid tentative definitions when
10380 // declaring variables in headers, but adding an intializer makes it a
10381 // defintion. This is somewhat confusing, so GCC and Clang both warn on it.
10382 // In C++, extern is often used to give implictly static const variables
10383 // external linkage, so don't warn in that case. If selectany is present,
10384 // this might be header code intended for C and C++ inclusion, so apply the
10386 if (VDecl->getStorageClass() == SC_Extern &&
10387 ((!getLangOpts().CPlusPlus && !VDecl->hasAttr<SelectAnyAttr>()) ||
10388 !Context.getBaseElementType(VDecl->getType()).isConstQualified()) &&
10389 !(getLangOpts().CPlusPlus && VDecl->isExternC()) &&
10390 !isTemplateInstantiation(VDecl->getTemplateSpecializationKind()))
10391 Diag(VDecl->getLocation(), diag::warn_extern_init);
10393 // C99 6.7.8p4. All file scoped initializers need to be constant.
10394 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl())
10395 CheckForConstantInitializer(Init, DclT);
10398 // We will represent direct-initialization similarly to copy-initialization:
10399 // int x(1); -as-> int x = 1;
10400 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c);
10402 // Clients that want to distinguish between the two forms, can check for
10403 // direct initializer using VarDecl::getInitStyle().
10404 // A major benefit is that clients that don't particularly care about which
10405 // exactly form was it (like the CodeGen) can handle both cases without
10406 // special case code.
10409 // The form of initialization (using parentheses or '=') is generally
10410 // insignificant, but does matter when the entity being initialized has a
10412 if (CXXDirectInit) {
10413 assert(DirectInit && "Call-style initializer must be direct init.");
10414 VDecl->setInitStyle(VarDecl::CallInit);
10415 } else if (DirectInit) {
10416 // This must be list-initialization. No other way is direct-initialization.
10417 VDecl->setInitStyle(VarDecl::ListInit);
10420 CheckCompleteVariableDeclaration(VDecl);
10423 /// ActOnInitializerError - Given that there was an error parsing an
10424 /// initializer for the given declaration, try to return to some form
10426 void Sema::ActOnInitializerError(Decl *D) {
10427 // Our main concern here is re-establishing invariants like "a
10428 // variable's type is either dependent or complete".
10429 if (!D || D->isInvalidDecl()) return;
10431 VarDecl *VD = dyn_cast<VarDecl>(D);
10434 // Bindings are not usable if we can't make sense of the initializer.
10435 if (auto *DD = dyn_cast<DecompositionDecl>(D))
10436 for (auto *BD : DD->bindings())
10437 BD->setInvalidDecl();
10439 // Auto types are meaningless if we can't make sense of the initializer.
10440 if (ParsingInitForAutoVars.count(D)) {
10441 D->setInvalidDecl();
10445 QualType Ty = VD->getType();
10446 if (Ty->isDependentType()) return;
10448 // Require a complete type.
10449 if (RequireCompleteType(VD->getLocation(),
10450 Context.getBaseElementType(Ty),
10451 diag::err_typecheck_decl_incomplete_type)) {
10452 VD->setInvalidDecl();
10456 // Require a non-abstract type.
10457 if (RequireNonAbstractType(VD->getLocation(), Ty,
10458 diag::err_abstract_type_in_decl,
10459 AbstractVariableType)) {
10460 VD->setInvalidDecl();
10464 // Don't bother complaining about constructors or destructors,
10468 void Sema::ActOnUninitializedDecl(Decl *RealDecl) {
10469 // If there is no declaration, there was an error parsing it. Just ignore it.
10473 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) {
10474 QualType Type = Var->getType();
10476 // C++1z [dcl.dcl]p1 grammar implies that an initializer is mandatory.
10477 if (isa<DecompositionDecl>(RealDecl)) {
10478 Diag(Var->getLocation(), diag::err_decomp_decl_requires_init) << Var;
10479 Var->setInvalidDecl();
10483 if (Type->isUndeducedType() &&
10484 DeduceVariableDeclarationType(Var, false, nullptr))
10487 // C++11 [class.static.data]p3: A static data member can be declared with
10488 // the constexpr specifier; if so, its declaration shall specify
10489 // a brace-or-equal-initializer.
10490 // C++11 [dcl.constexpr]p1: The constexpr specifier shall be applied only to
10491 // the definition of a variable [...] or the declaration of a static data
10493 if (Var->isConstexpr() && !Var->isThisDeclarationADefinition() &&
10494 !Var->isThisDeclarationADemotedDefinition()) {
10495 if (Var->isStaticDataMember()) {
10496 // C++1z removes the relevant rule; the in-class declaration is always
10497 // a definition there.
10498 if (!getLangOpts().CPlusPlus1z) {
10499 Diag(Var->getLocation(),
10500 diag::err_constexpr_static_mem_var_requires_init)
10501 << Var->getDeclName();
10502 Var->setInvalidDecl();
10506 Diag(Var->getLocation(), diag::err_invalid_constexpr_var_decl);
10507 Var->setInvalidDecl();
10512 // C++ Concepts TS [dcl.spec.concept]p1: [...] A variable template
10513 // definition having the concept specifier is called a variable concept. A
10514 // concept definition refers to [...] a variable concept and its initializer.
10515 if (VarTemplateDecl *VTD = Var->getDescribedVarTemplate()) {
10516 if (VTD->isConcept()) {
10517 Diag(Var->getLocation(), diag::err_var_concept_not_initialized);
10518 Var->setInvalidDecl();
10523 // OpenCL v1.1 s6.5.3: variables declared in the constant address space must
10525 if (!Var->isInvalidDecl() &&
10526 Var->getType().getAddressSpace() == LangAS::opencl_constant &&
10527 Var->getStorageClass() != SC_Extern && !Var->getInit()) {
10528 Diag(Var->getLocation(), diag::err_opencl_constant_no_init);
10529 Var->setInvalidDecl();
10533 switch (Var->isThisDeclarationADefinition()) {
10534 case VarDecl::Definition:
10535 if (!Var->isStaticDataMember() || !Var->getAnyInitializer())
10538 // We have an out-of-line definition of a static data member
10539 // that has an in-class initializer, so we type-check this like
10544 case VarDecl::DeclarationOnly:
10545 // It's only a declaration.
10547 // Block scope. C99 6.7p7: If an identifier for an object is
10548 // declared with no linkage (C99 6.2.2p6), the type for the
10549 // object shall be complete.
10550 if (!Type->isDependentType() && Var->isLocalVarDecl() &&
10551 !Var->hasLinkage() && !Var->isInvalidDecl() &&
10552 RequireCompleteType(Var->getLocation(), Type,
10553 diag::err_typecheck_decl_incomplete_type))
10554 Var->setInvalidDecl();
10556 // Make sure that the type is not abstract.
10557 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
10558 RequireNonAbstractType(Var->getLocation(), Type,
10559 diag::err_abstract_type_in_decl,
10560 AbstractVariableType))
10561 Var->setInvalidDecl();
10562 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
10563 Var->getStorageClass() == SC_PrivateExtern) {
10564 Diag(Var->getLocation(), diag::warn_private_extern);
10565 Diag(Var->getLocation(), diag::note_private_extern);
10570 case VarDecl::TentativeDefinition:
10571 // File scope. C99 6.9.2p2: A declaration of an identifier for an
10572 // object that has file scope without an initializer, and without a
10573 // storage-class specifier or with the storage-class specifier "static",
10574 // constitutes a tentative definition. Note: A tentative definition with
10575 // external linkage is valid (C99 6.2.2p5).
10576 if (!Var->isInvalidDecl()) {
10577 if (const IncompleteArrayType *ArrayT
10578 = Context.getAsIncompleteArrayType(Type)) {
10579 if (RequireCompleteType(Var->getLocation(),
10580 ArrayT->getElementType(),
10581 diag::err_illegal_decl_array_incomplete_type))
10582 Var->setInvalidDecl();
10583 } else if (Var->getStorageClass() == SC_Static) {
10584 // C99 6.9.2p3: If the declaration of an identifier for an object is
10585 // a tentative definition and has internal linkage (C99 6.2.2p3), the
10586 // declared type shall not be an incomplete type.
10587 // NOTE: code such as the following
10588 // static struct s;
10589 // struct s { int a; };
10590 // is accepted by gcc. Hence here we issue a warning instead of
10591 // an error and we do not invalidate the static declaration.
10592 // NOTE: to avoid multiple warnings, only check the first declaration.
10593 if (Var->isFirstDecl())
10594 RequireCompleteType(Var->getLocation(), Type,
10595 diag::ext_typecheck_decl_incomplete_type);
10599 // Record the tentative definition; we're done.
10600 if (!Var->isInvalidDecl())
10601 TentativeDefinitions.push_back(Var);
10605 // Provide a specific diagnostic for uninitialized variable
10606 // definitions with incomplete array type.
10607 if (Type->isIncompleteArrayType()) {
10608 Diag(Var->getLocation(),
10609 diag::err_typecheck_incomplete_array_needs_initializer);
10610 Var->setInvalidDecl();
10614 // Provide a specific diagnostic for uninitialized variable
10615 // definitions with reference type.
10616 if (Type->isReferenceType()) {
10617 Diag(Var->getLocation(), diag::err_reference_var_requires_init)
10618 << Var->getDeclName()
10619 << SourceRange(Var->getLocation(), Var->getLocation());
10620 Var->setInvalidDecl();
10624 // Do not attempt to type-check the default initializer for a
10625 // variable with dependent type.
10626 if (Type->isDependentType())
10629 if (Var->isInvalidDecl())
10632 if (!Var->hasAttr<AliasAttr>()) {
10633 if (RequireCompleteType(Var->getLocation(),
10634 Context.getBaseElementType(Type),
10635 diag::err_typecheck_decl_incomplete_type)) {
10636 Var->setInvalidDecl();
10643 // The variable can not have an abstract class type.
10644 if (RequireNonAbstractType(Var->getLocation(), Type,
10645 diag::err_abstract_type_in_decl,
10646 AbstractVariableType)) {
10647 Var->setInvalidDecl();
10651 // Check for jumps past the implicit initializer. C++0x
10652 // clarifies that this applies to a "variable with automatic
10653 // storage duration", not a "local variable".
10654 // C++11 [stmt.dcl]p3
10655 // A program that jumps from a point where a variable with automatic
10656 // storage duration is not in scope to a point where it is in scope is
10657 // ill-formed unless the variable has scalar type, class type with a
10658 // trivial default constructor and a trivial destructor, a cv-qualified
10659 // version of one of these types, or an array of one of the preceding
10660 // types and is declared without an initializer.
10661 if (getLangOpts().CPlusPlus && Var->hasLocalStorage()) {
10662 if (const RecordType *Record
10663 = Context.getBaseElementType(Type)->getAs<RecordType>()) {
10664 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl());
10665 // Mark the function for further checking even if the looser rules of
10666 // C++11 do not require such checks, so that we can diagnose
10667 // incompatibilities with C++98.
10668 if (!CXXRecord->isPOD())
10669 getCurFunction()->setHasBranchProtectedScope();
10673 // C++03 [dcl.init]p9:
10674 // If no initializer is specified for an object, and the
10675 // object is of (possibly cv-qualified) non-POD class type (or
10676 // array thereof), the object shall be default-initialized; if
10677 // the object is of const-qualified type, the underlying class
10678 // type shall have a user-declared default
10679 // constructor. Otherwise, if no initializer is specified for
10680 // a non- static object, the object and its subobjects, if
10681 // any, have an indeterminate initial value); if the object
10682 // or any of its subobjects are of const-qualified type, the
10683 // program is ill-formed.
10684 // C++0x [dcl.init]p11:
10685 // If no initializer is specified for an object, the object is
10686 // default-initialized; [...].
10687 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var);
10688 InitializationKind Kind
10689 = InitializationKind::CreateDefault(Var->getLocation());
10691 InitializationSequence InitSeq(*this, Entity, Kind, None);
10692 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, None);
10693 if (Init.isInvalid())
10694 Var->setInvalidDecl();
10695 else if (Init.get()) {
10696 Var->setInit(MaybeCreateExprWithCleanups(Init.get()));
10697 // This is important for template substitution.
10698 Var->setInitStyle(VarDecl::CallInit);
10701 CheckCompleteVariableDeclaration(Var);
10705 void Sema::ActOnCXXForRangeDecl(Decl *D) {
10706 // If there is no declaration, there was an error parsing it. Ignore it.
10710 VarDecl *VD = dyn_cast<VarDecl>(D);
10712 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var);
10713 D->setInvalidDecl();
10717 VD->setCXXForRangeDecl(true);
10719 // for-range-declaration cannot be given a storage class specifier.
10721 switch (VD->getStorageClass()) {
10730 case SC_PrivateExtern:
10741 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class)
10742 << VD->getDeclName() << Error;
10743 D->setInvalidDecl();
10748 Sema::ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
10749 IdentifierInfo *Ident,
10750 ParsedAttributes &Attrs,
10751 SourceLocation AttrEnd) {
10752 // C++1y [stmt.iter]p1:
10753 // A range-based for statement of the form
10754 // for ( for-range-identifier : for-range-initializer ) statement
10755 // is equivalent to
10756 // for ( auto&& for-range-identifier : for-range-initializer ) statement
10757 DeclSpec DS(Attrs.getPool().getFactory());
10759 const char *PrevSpec;
10761 DS.SetTypeSpecType(DeclSpec::TST_auto, IdentLoc, PrevSpec, DiagID,
10762 getPrintingPolicy());
10764 Declarator D(DS, Declarator::ForContext);
10765 D.SetIdentifier(Ident, IdentLoc);
10766 D.takeAttributes(Attrs, AttrEnd);
10768 ParsedAttributes EmptyAttrs(Attrs.getPool().getFactory());
10769 D.AddTypeInfo(DeclaratorChunk::getReference(0, IdentLoc, /*lvalue*/false),
10770 EmptyAttrs, IdentLoc);
10771 Decl *Var = ActOnDeclarator(S, D);
10772 cast<VarDecl>(Var)->setCXXForRangeDecl(true);
10773 FinalizeDeclaration(Var);
10774 return ActOnDeclStmt(FinalizeDeclaratorGroup(S, DS, Var), IdentLoc,
10775 AttrEnd.isValid() ? AttrEnd : IdentLoc);
10778 void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
10779 if (var->isInvalidDecl()) return;
10781 if (getLangOpts().OpenCL) {
10782 // OpenCL v2.0 s6.12.5 - Every block variable declaration must have an
10784 if (var->getTypeSourceInfo()->getType()->isBlockPointerType() &&
10786 Diag(var->getLocation(), diag::err_opencl_invalid_block_declaration)
10788 var->setInvalidDecl();
10793 // In Objective-C, don't allow jumps past the implicit initialization of a
10794 // local retaining variable.
10795 if (getLangOpts().ObjC1 &&
10796 var->hasLocalStorage()) {
10797 switch (var->getType().getObjCLifetime()) {
10798 case Qualifiers::OCL_None:
10799 case Qualifiers::OCL_ExplicitNone:
10800 case Qualifiers::OCL_Autoreleasing:
10803 case Qualifiers::OCL_Weak:
10804 case Qualifiers::OCL_Strong:
10805 getCurFunction()->setHasBranchProtectedScope();
10810 // Warn about externally-visible variables being defined without a
10811 // prior declaration. We only want to do this for global
10812 // declarations, but we also specifically need to avoid doing it for
10813 // class members because the linkage of an anonymous class can
10814 // change if it's later given a typedef name.
10815 if (var->isThisDeclarationADefinition() &&
10816 var->getDeclContext()->getRedeclContext()->isFileContext() &&
10817 var->isExternallyVisible() && var->hasLinkage() &&
10818 !getDiagnostics().isIgnored(diag::warn_missing_variable_declarations,
10819 var->getLocation())) {
10820 // Find a previous declaration that's not a definition.
10821 VarDecl *prev = var->getPreviousDecl();
10822 while (prev && prev->isThisDeclarationADefinition())
10823 prev = prev->getPreviousDecl();
10826 Diag(var->getLocation(), diag::warn_missing_variable_declarations) << var;
10829 // Cache the result of checking for constant initialization.
10830 Optional<bool> CacheHasConstInit;
10831 const Expr *CacheCulprit;
10832 auto checkConstInit = [&]() mutable {
10833 if (!CacheHasConstInit)
10834 CacheHasConstInit = var->getInit()->isConstantInitializer(
10835 Context, var->getType()->isReferenceType(), &CacheCulprit);
10836 return *CacheHasConstInit;
10839 if (var->getTLSKind() == VarDecl::TLS_Static) {
10840 if (var->getType().isDestructedType()) {
10841 // GNU C++98 edits for __thread, [basic.start.term]p3:
10842 // The type of an object with thread storage duration shall not
10843 // have a non-trivial destructor.
10844 Diag(var->getLocation(), diag::err_thread_nontrivial_dtor);
10845 if (getLangOpts().CPlusPlus11)
10846 Diag(var->getLocation(), diag::note_use_thread_local);
10847 } else if (getLangOpts().CPlusPlus && var->hasInit()) {
10848 if (!checkConstInit()) {
10849 // GNU C++98 edits for __thread, [basic.start.init]p4:
10850 // An object of thread storage duration shall not require dynamic
10852 // FIXME: Need strict checking here.
10853 Diag(CacheCulprit->getExprLoc(), diag::err_thread_dynamic_init)
10854 << CacheCulprit->getSourceRange();
10855 if (getLangOpts().CPlusPlus11)
10856 Diag(var->getLocation(), diag::note_use_thread_local);
10861 // Apply section attributes and pragmas to global variables.
10862 bool GlobalStorage = var->hasGlobalStorage();
10863 if (GlobalStorage && var->isThisDeclarationADefinition() &&
10864 !inTemplateInstantiation()) {
10865 PragmaStack<StringLiteral *> *Stack = nullptr;
10866 int SectionFlags = ASTContext::PSF_Implicit | ASTContext::PSF_Read;
10867 if (var->getType().isConstQualified())
10868 Stack = &ConstSegStack;
10869 else if (!var->getInit()) {
10870 Stack = &BSSSegStack;
10871 SectionFlags |= ASTContext::PSF_Write;
10873 Stack = &DataSegStack;
10874 SectionFlags |= ASTContext::PSF_Write;
10876 if (Stack->CurrentValue && !var->hasAttr<SectionAttr>()) {
10877 var->addAttr(SectionAttr::CreateImplicit(
10878 Context, SectionAttr::Declspec_allocate,
10879 Stack->CurrentValue->getString(), Stack->CurrentPragmaLocation));
10881 if (const SectionAttr *SA = var->getAttr<SectionAttr>())
10882 if (UnifySection(SA->getName(), SectionFlags, var))
10883 var->dropAttr<SectionAttr>();
10885 // Apply the init_seg attribute if this has an initializer. If the
10886 // initializer turns out to not be dynamic, we'll end up ignoring this
10888 if (CurInitSeg && var->getInit())
10889 var->addAttr(InitSegAttr::CreateImplicit(Context, CurInitSeg->getString(),
10893 // All the following checks are C++ only.
10894 if (!getLangOpts().CPlusPlus) {
10895 // If this variable must be emitted, add it as an initializer for the
10897 if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
10898 Context.addModuleInitializer(ModuleScopes.back().Module, var);
10902 if (auto *DD = dyn_cast<DecompositionDecl>(var))
10903 CheckCompleteDecompositionDeclaration(DD);
10905 QualType type = var->getType();
10906 if (type->isDependentType()) return;
10908 // __block variables might require us to capture a copy-initializer.
10909 if (var->hasAttr<BlocksAttr>()) {
10910 // It's currently invalid to ever have a __block variable with an
10911 // array type; should we diagnose that here?
10913 // Regardless, we don't want to ignore array nesting when
10914 // constructing this copy.
10915 if (type->isStructureOrClassType()) {
10916 EnterExpressionEvaluationContext scope(
10917 *this, ExpressionEvaluationContext::PotentiallyEvaluated);
10918 SourceLocation poi = var->getLocation();
10919 Expr *varRef =new (Context) DeclRefExpr(var, false, type, VK_LValue, poi);
10921 = PerformMoveOrCopyInitialization(
10922 InitializedEntity::InitializeBlock(poi, type, false),
10923 var, var->getType(), varRef, /*AllowNRVO=*/true);
10924 if (!result.isInvalid()) {
10925 result = MaybeCreateExprWithCleanups(result);
10926 Expr *init = result.getAs<Expr>();
10927 Context.setBlockVarCopyInits(var, init);
10932 Expr *Init = var->getInit();
10933 bool IsGlobal = GlobalStorage && !var->isStaticLocal();
10934 QualType baseType = Context.getBaseElementType(type);
10936 if (!var->getDeclContext()->isDependentContext() &&
10937 Init && !Init->isValueDependent()) {
10939 if (var->isConstexpr()) {
10940 SmallVector<PartialDiagnosticAt, 8> Notes;
10941 if (!var->evaluateValue(Notes) || !var->isInitICE()) {
10942 SourceLocation DiagLoc = var->getLocation();
10943 // If the note doesn't add any useful information other than a source
10944 // location, fold it into the primary diagnostic.
10945 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
10946 diag::note_invalid_subexpr_in_const_expr) {
10947 DiagLoc = Notes[0].first;
10950 Diag(DiagLoc, diag::err_constexpr_var_requires_const_init)
10951 << var << Init->getSourceRange();
10952 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
10953 Diag(Notes[I].first, Notes[I].second);
10955 } else if (var->isUsableInConstantExpressions(Context)) {
10956 // Check whether the initializer of a const variable of integral or
10957 // enumeration type is an ICE now, since we can't tell whether it was
10958 // initialized by a constant expression if we check later.
10959 var->checkInitIsICE();
10962 // Don't emit further diagnostics about constexpr globals since they
10963 // were just diagnosed.
10964 if (!var->isConstexpr() && GlobalStorage &&
10965 var->hasAttr<RequireConstantInitAttr>()) {
10966 // FIXME: Need strict checking in C++03 here.
10967 bool DiagErr = getLangOpts().CPlusPlus11
10968 ? !var->checkInitIsICE() : !checkConstInit();
10970 auto attr = var->getAttr<RequireConstantInitAttr>();
10971 Diag(var->getLocation(), diag::err_require_constant_init_failed)
10972 << Init->getSourceRange();
10973 Diag(attr->getLocation(), diag::note_declared_required_constant_init_here)
10974 << attr->getRange();
10977 else if (!var->isConstexpr() && IsGlobal &&
10978 !getDiagnostics().isIgnored(diag::warn_global_constructor,
10979 var->getLocation())) {
10980 // Warn about globals which don't have a constant initializer. Don't
10981 // warn about globals with a non-trivial destructor because we already
10982 // warned about them.
10983 CXXRecordDecl *RD = baseType->getAsCXXRecordDecl();
10984 if (!(RD && !RD->hasTrivialDestructor())) {
10985 if (!checkConstInit())
10986 Diag(var->getLocation(), diag::warn_global_constructor)
10987 << Init->getSourceRange();
10992 // Require the destructor.
10993 if (const RecordType *recordType = baseType->getAs<RecordType>())
10994 FinalizeVarWithDestructor(var, recordType);
10996 // If this variable must be emitted, add it as an initializer for the current
10998 if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
10999 Context.addModuleInitializer(ModuleScopes.back().Module, var);
11002 /// \brief Determines if a variable's alignment is dependent.
11003 static bool hasDependentAlignment(VarDecl *VD) {
11004 if (VD->getType()->isDependentType())
11006 for (auto *I : VD->specific_attrs<AlignedAttr>())
11007 if (I->isAlignmentDependent())
11012 /// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform
11013 /// any semantic actions necessary after any initializer has been attached.
11015 Sema::FinalizeDeclaration(Decl *ThisDecl) {
11016 // Note that we are no longer parsing the initializer for this declaration.
11017 ParsingInitForAutoVars.erase(ThisDecl);
11019 VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDecl);
11023 if (auto *DD = dyn_cast<DecompositionDecl>(ThisDecl)) {
11024 for (auto *BD : DD->bindings()) {
11025 FinalizeDeclaration(BD);
11029 checkAttributesAfterMerging(*this, *VD);
11031 // Perform TLS alignment check here after attributes attached to the variable
11032 // which may affect the alignment have been processed. Only perform the check
11033 // if the target has a maximum TLS alignment (zero means no constraints).
11034 if (unsigned MaxAlign = Context.getTargetInfo().getMaxTLSAlign()) {
11035 // Protect the check so that it's not performed on dependent types and
11036 // dependent alignments (we can't determine the alignment in that case).
11037 if (VD->getTLSKind() && !hasDependentAlignment(VD) &&
11038 !VD->isInvalidDecl()) {
11039 CharUnits MaxAlignChars = Context.toCharUnitsFromBits(MaxAlign);
11040 if (Context.getDeclAlign(VD) > MaxAlignChars) {
11041 Diag(VD->getLocation(), diag::err_tls_var_aligned_over_maximum)
11042 << (unsigned)Context.getDeclAlign(VD).getQuantity() << VD
11043 << (unsigned)MaxAlignChars.getQuantity();
11048 if (VD->isStaticLocal()) {
11049 if (FunctionDecl *FD =
11050 dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod())) {
11051 // Static locals inherit dll attributes from their function.
11052 if (Attr *A = getDLLAttr(FD)) {
11053 auto *NewAttr = cast<InheritableAttr>(A->clone(getASTContext()));
11054 NewAttr->setInherited(true);
11055 VD->addAttr(NewAttr);
11057 // CUDA E.2.9.4: Within the body of a __device__ or __global__
11058 // function, only __shared__ variables may be declared with
11059 // static storage class.
11060 if (getLangOpts().CUDA && !VD->hasAttr<CUDASharedAttr>() &&
11061 CUDADiagIfDeviceCode(VD->getLocation(),
11062 diag::err_device_static_local_var)
11063 << CurrentCUDATarget())
11064 VD->setInvalidDecl();
11068 // Perform check for initializers of device-side global variables.
11069 // CUDA allows empty constructors as initializers (see E.2.3.1, CUDA
11070 // 7.5). We must also apply the same checks to all __shared__
11071 // variables whether they are local or not. CUDA also allows
11072 // constant initializers for __constant__ and __device__ variables.
11073 if (getLangOpts().CUDA) {
11074 const Expr *Init = VD->getInit();
11075 if (Init && VD->hasGlobalStorage()) {
11076 if (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>() ||
11077 VD->hasAttr<CUDASharedAttr>()) {
11078 assert(!VD->isStaticLocal() || VD->hasAttr<CUDASharedAttr>());
11079 bool AllowedInit = false;
11080 if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(Init))
11082 isEmptyCudaConstructor(VD->getLocation(), CE->getConstructor());
11083 // We'll allow constant initializers even if it's a non-empty
11084 // constructor according to CUDA rules. This deviates from NVCC,
11085 // but allows us to handle things like constexpr constructors.
11086 if (!AllowedInit &&
11087 (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>()))
11088 AllowedInit = VD->getInit()->isConstantInitializer(
11089 Context, VD->getType()->isReferenceType());
11091 // Also make sure that destructor, if there is one, is empty.
11093 if (CXXRecordDecl *RD = VD->getType()->getAsCXXRecordDecl())
11095 isEmptyCudaDestructor(VD->getLocation(), RD->getDestructor());
11097 if (!AllowedInit) {
11098 Diag(VD->getLocation(), VD->hasAttr<CUDASharedAttr>()
11099 ? diag::err_shared_var_init
11100 : diag::err_dynamic_var_init)
11101 << Init->getSourceRange();
11102 VD->setInvalidDecl();
11105 // This is a host-side global variable. Check that the initializer is
11106 // callable from the host side.
11107 const FunctionDecl *InitFn = nullptr;
11108 if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(Init)) {
11109 InitFn = CE->getConstructor();
11110 } else if (const CallExpr *CE = dyn_cast<CallExpr>(Init)) {
11111 InitFn = CE->getDirectCallee();
11114 CUDAFunctionTarget InitFnTarget = IdentifyCUDATarget(InitFn);
11115 if (InitFnTarget != CFT_Host && InitFnTarget != CFT_HostDevice) {
11116 Diag(VD->getLocation(), diag::err_ref_bad_target_global_initializer)
11117 << InitFnTarget << InitFn;
11118 Diag(InitFn->getLocation(), diag::note_previous_decl) << InitFn;
11119 VD->setInvalidDecl();
11126 // Grab the dllimport or dllexport attribute off of the VarDecl.
11127 const InheritableAttr *DLLAttr = getDLLAttr(VD);
11129 // Imported static data members cannot be defined out-of-line.
11130 if (const auto *IA = dyn_cast_or_null<DLLImportAttr>(DLLAttr)) {
11131 if (VD->isStaticDataMember() && VD->isOutOfLine() &&
11132 VD->isThisDeclarationADefinition()) {
11133 // We allow definitions of dllimport class template static data members
11135 CXXRecordDecl *Context =
11136 cast<CXXRecordDecl>(VD->getFirstDecl()->getDeclContext());
11137 bool IsClassTemplateMember =
11138 isa<ClassTemplatePartialSpecializationDecl>(Context) ||
11139 Context->getDescribedClassTemplate();
11141 Diag(VD->getLocation(),
11142 IsClassTemplateMember
11143 ? diag::warn_attribute_dllimport_static_field_definition
11144 : diag::err_attribute_dllimport_static_field_definition);
11145 Diag(IA->getLocation(), diag::note_attribute);
11146 if (!IsClassTemplateMember)
11147 VD->setInvalidDecl();
11151 // dllimport/dllexport variables cannot be thread local, their TLS index
11152 // isn't exported with the variable.
11153 if (DLLAttr && VD->getTLSKind()) {
11154 auto *F = dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod());
11155 if (F && getDLLAttr(F)) {
11156 assert(VD->isStaticLocal());
11157 // But if this is a static local in a dlimport/dllexport function, the
11158 // function will never be inlined, which means the var would never be
11159 // imported, so having it marked import/export is safe.
11161 Diag(VD->getLocation(), diag::err_attribute_dll_thread_local) << VD
11163 VD->setInvalidDecl();
11167 if (UsedAttr *Attr = VD->getAttr<UsedAttr>()) {
11168 if (!Attr->isInherited() && !VD->isThisDeclarationADefinition()) {
11169 Diag(Attr->getLocation(), diag::warn_attribute_ignored) << Attr;
11170 VD->dropAttr<UsedAttr>();
11174 const DeclContext *DC = VD->getDeclContext();
11175 // If there's a #pragma GCC visibility in scope, and this isn't a class
11176 // member, set the visibility of this variable.
11177 if (DC->getRedeclContext()->isFileContext() && VD->isExternallyVisible())
11178 AddPushedVisibilityAttribute(VD);
11180 // FIXME: Warn on unused templates.
11181 if (VD->isFileVarDecl() && !VD->getDescribedVarTemplate() &&
11182 !isa<VarTemplatePartialSpecializationDecl>(VD))
11183 MarkUnusedFileScopedDecl(VD);
11185 // Now we have parsed the initializer and can update the table of magic
11187 if (!VD->hasAttr<TypeTagForDatatypeAttr>() ||
11188 !VD->getType()->isIntegralOrEnumerationType())
11191 for (const auto *I : ThisDecl->specific_attrs<TypeTagForDatatypeAttr>()) {
11192 const Expr *MagicValueExpr = VD->getInit();
11193 if (!MagicValueExpr) {
11196 llvm::APSInt MagicValueInt;
11197 if (!MagicValueExpr->isIntegerConstantExpr(MagicValueInt, Context)) {
11198 Diag(I->getRange().getBegin(),
11199 diag::err_type_tag_for_datatype_not_ice)
11200 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
11203 if (MagicValueInt.getActiveBits() > 64) {
11204 Diag(I->getRange().getBegin(),
11205 diag::err_type_tag_for_datatype_too_large)
11206 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
11209 uint64_t MagicValue = MagicValueInt.getZExtValue();
11210 RegisterTypeTagForDatatype(I->getArgumentKind(),
11212 I->getMatchingCType(),
11213 I->getLayoutCompatible(),
11214 I->getMustBeNull());
11218 static bool hasDeducedAuto(DeclaratorDecl *DD) {
11219 auto *VD = dyn_cast<VarDecl>(DD);
11220 return VD && !VD->getType()->hasAutoForTrailingReturnType();
11223 Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
11224 ArrayRef<Decl *> Group) {
11225 SmallVector<Decl*, 8> Decls;
11227 if (DS.isTypeSpecOwned())
11228 Decls.push_back(DS.getRepAsDecl());
11230 DeclaratorDecl *FirstDeclaratorInGroup = nullptr;
11231 DecompositionDecl *FirstDecompDeclaratorInGroup = nullptr;
11232 bool DiagnosedMultipleDecomps = false;
11233 DeclaratorDecl *FirstNonDeducedAutoInGroup = nullptr;
11234 bool DiagnosedNonDeducedAuto = false;
11236 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
11237 if (Decl *D = Group[i]) {
11238 // For declarators, there are some additional syntactic-ish checks we need
11240 if (auto *DD = dyn_cast<DeclaratorDecl>(D)) {
11241 if (!FirstDeclaratorInGroup)
11242 FirstDeclaratorInGroup = DD;
11243 if (!FirstDecompDeclaratorInGroup)
11244 FirstDecompDeclaratorInGroup = dyn_cast<DecompositionDecl>(D);
11245 if (!FirstNonDeducedAutoInGroup && DS.hasAutoTypeSpec() &&
11246 !hasDeducedAuto(DD))
11247 FirstNonDeducedAutoInGroup = DD;
11249 if (FirstDeclaratorInGroup != DD) {
11250 // A decomposition declaration cannot be combined with any other
11251 // declaration in the same group.
11252 if (FirstDecompDeclaratorInGroup && !DiagnosedMultipleDecomps) {
11253 Diag(FirstDecompDeclaratorInGroup->getLocation(),
11254 diag::err_decomp_decl_not_alone)
11255 << FirstDeclaratorInGroup->getSourceRange()
11256 << DD->getSourceRange();
11257 DiagnosedMultipleDecomps = true;
11260 // A declarator that uses 'auto' in any way other than to declare a
11261 // variable with a deduced type cannot be combined with any other
11262 // declarator in the same group.
11263 if (FirstNonDeducedAutoInGroup && !DiagnosedNonDeducedAuto) {
11264 Diag(FirstNonDeducedAutoInGroup->getLocation(),
11265 diag::err_auto_non_deduced_not_alone)
11266 << FirstNonDeducedAutoInGroup->getType()
11267 ->hasAutoForTrailingReturnType()
11268 << FirstDeclaratorInGroup->getSourceRange()
11269 << DD->getSourceRange();
11270 DiagnosedNonDeducedAuto = true;
11275 Decls.push_back(D);
11279 if (DeclSpec::isDeclRep(DS.getTypeSpecType())) {
11280 if (TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) {
11281 handleTagNumbering(Tag, S);
11282 if (FirstDeclaratorInGroup && !Tag->hasNameForLinkage() &&
11283 getLangOpts().CPlusPlus)
11284 Context.addDeclaratorForUnnamedTagDecl(Tag, FirstDeclaratorInGroup);
11288 return BuildDeclaratorGroup(Decls);
11291 /// BuildDeclaratorGroup - convert a list of declarations into a declaration
11292 /// group, performing any necessary semantic checking.
11293 Sema::DeclGroupPtrTy
11294 Sema::BuildDeclaratorGroup(MutableArrayRef<Decl *> Group) {
11295 // C++14 [dcl.spec.auto]p7: (DR1347)
11296 // If the type that replaces the placeholder type is not the same in each
11297 // deduction, the program is ill-formed.
11298 if (Group.size() > 1) {
11300 VarDecl *DeducedDecl = nullptr;
11301 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
11302 VarDecl *D = dyn_cast<VarDecl>(Group[i]);
11303 if (!D || D->isInvalidDecl())
11305 DeducedType *DT = D->getType()->getContainedDeducedType();
11306 if (!DT || DT->getDeducedType().isNull())
11308 if (Deduced.isNull()) {
11309 Deduced = DT->getDeducedType();
11311 } else if (!Context.hasSameType(DT->getDeducedType(), Deduced)) {
11312 auto *AT = dyn_cast<AutoType>(DT);
11313 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(),
11314 diag::err_auto_different_deductions)
11315 << (AT ? (unsigned)AT->getKeyword() : 3)
11316 << Deduced << DeducedDecl->getDeclName()
11317 << DT->getDeducedType() << D->getDeclName()
11318 << DeducedDecl->getInit()->getSourceRange()
11319 << D->getInit()->getSourceRange();
11320 D->setInvalidDecl();
11326 ActOnDocumentableDecls(Group);
11328 return DeclGroupPtrTy::make(
11329 DeclGroupRef::Create(Context, Group.data(), Group.size()));
11332 void Sema::ActOnDocumentableDecl(Decl *D) {
11333 ActOnDocumentableDecls(D);
11336 void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) {
11337 // Don't parse the comment if Doxygen diagnostics are ignored.
11338 if (Group.empty() || !Group[0])
11341 if (Diags.isIgnored(diag::warn_doc_param_not_found,
11342 Group[0]->getLocation()) &&
11343 Diags.isIgnored(diag::warn_unknown_comment_command_name,
11344 Group[0]->getLocation()))
11347 if (Group.size() >= 2) {
11348 // This is a decl group. Normally it will contain only declarations
11349 // produced from declarator list. But in case we have any definitions or
11350 // additional declaration references:
11351 // 'typedef struct S {} S;'
11352 // 'typedef struct S *S;'
11354 // FinalizeDeclaratorGroup adds these as separate declarations.
11355 Decl *MaybeTagDecl = Group[0];
11356 if (MaybeTagDecl && isa<TagDecl>(MaybeTagDecl)) {
11357 Group = Group.slice(1);
11361 // See if there are any new comments that are not attached to a decl.
11362 ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments();
11363 if (!Comments.empty() &&
11364 !Comments.back()->isAttached()) {
11365 // There is at least one comment that not attached to a decl.
11366 // Maybe it should be attached to one of these decls?
11368 // Note that this way we pick up not only comments that precede the
11369 // declaration, but also comments that *follow* the declaration -- thanks to
11370 // the lookahead in the lexer: we've consumed the semicolon and looked
11371 // ahead through comments.
11372 for (unsigned i = 0, e = Group.size(); i != e; ++i)
11373 Context.getCommentForDecl(Group[i], &PP);
11377 /// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator()
11378 /// to introduce parameters into function prototype scope.
11379 Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) {
11380 const DeclSpec &DS = D.getDeclSpec();
11382 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'.
11384 // C++03 [dcl.stc]p2 also permits 'auto'.
11385 StorageClass SC = SC_None;
11386 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
11388 } else if (getLangOpts().CPlusPlus &&
11389 DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
11391 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) {
11392 Diag(DS.getStorageClassSpecLoc(),
11393 diag::err_invalid_storage_class_in_func_decl);
11394 D.getMutableDeclSpec().ClearStorageClassSpecs();
11397 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
11398 Diag(DS.getThreadStorageClassSpecLoc(), diag::err_invalid_thread)
11399 << DeclSpec::getSpecifierName(TSCS);
11400 if (DS.isInlineSpecified())
11401 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
11402 << getLangOpts().CPlusPlus1z;
11403 if (DS.isConstexprSpecified())
11404 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr)
11406 if (DS.isConceptSpecified())
11407 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
11409 DiagnoseFunctionSpecifiers(DS);
11411 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
11412 QualType parmDeclType = TInfo->getType();
11414 if (getLangOpts().CPlusPlus) {
11415 // Check that there are no default arguments inside the type of this
11417 CheckExtraCXXDefaultArguments(D);
11419 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
11420 if (D.getCXXScopeSpec().isSet()) {
11421 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator)
11422 << D.getCXXScopeSpec().getRange();
11423 D.getCXXScopeSpec().clear();
11427 // Ensure we have a valid name
11428 IdentifierInfo *II = nullptr;
11430 II = D.getIdentifier();
11432 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name)
11433 << GetNameForDeclarator(D).getName();
11434 D.setInvalidType(true);
11438 // Check for redeclaration of parameters, e.g. int foo(int x, int x);
11440 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName,
11443 if (R.isSingleResult()) {
11444 NamedDecl *PrevDecl = R.getFoundDecl();
11445 if (PrevDecl->isTemplateParameter()) {
11446 // Maybe we will complain about the shadowed template parameter.
11447 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
11448 // Just pretend that we didn't see the previous declaration.
11449 PrevDecl = nullptr;
11450 } else if (S->isDeclScope(PrevDecl)) {
11451 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II;
11452 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
11454 // Recover by removing the name
11456 D.SetIdentifier(nullptr, D.getIdentifierLoc());
11457 D.setInvalidType(true);
11462 // Temporarily put parameter variables in the translation unit, not
11463 // the enclosing context. This prevents them from accidentally
11464 // looking like class members in C++.
11465 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(),
11467 D.getIdentifierLoc(), II,
11468 parmDeclType, TInfo,
11471 if (D.isInvalidType())
11472 New->setInvalidDecl();
11474 assert(S->isFunctionPrototypeScope());
11475 assert(S->getFunctionPrototypeDepth() >= 1);
11476 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1,
11477 S->getNextFunctionPrototypeIndex());
11479 // Add the parameter declaration into this scope.
11482 IdResolver.AddDecl(New);
11484 ProcessDeclAttributes(S, New, D);
11486 if (D.getDeclSpec().isModulePrivateSpecified())
11487 Diag(New->getLocation(), diag::err_module_private_local)
11488 << 1 << New->getDeclName()
11489 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
11490 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
11492 if (New->hasAttr<BlocksAttr>()) {
11493 Diag(New->getLocation(), diag::err_block_on_nonlocal);
11498 /// \brief Synthesizes a variable for a parameter arising from a
11500 ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC,
11501 SourceLocation Loc,
11503 /* FIXME: setting StartLoc == Loc.
11504 Would it be worth to modify callers so as to provide proper source
11505 location for the unnamed parameters, embedding the parameter's type? */
11506 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, nullptr,
11507 T, Context.getTrivialTypeSourceInfo(T, Loc),
11509 Param->setImplicit();
11513 void Sema::DiagnoseUnusedParameters(ArrayRef<ParmVarDecl *> Parameters) {
11514 // Don't diagnose unused-parameter errors in template instantiations; we
11515 // will already have done so in the template itself.
11516 if (inTemplateInstantiation())
11519 for (const ParmVarDecl *Parameter : Parameters) {
11520 if (!Parameter->isReferenced() && Parameter->getDeclName() &&
11521 !Parameter->hasAttr<UnusedAttr>()) {
11522 Diag(Parameter->getLocation(), diag::warn_unused_parameter)
11523 << Parameter->getDeclName();
11528 void Sema::DiagnoseSizeOfParametersAndReturnValue(
11529 ArrayRef<ParmVarDecl *> Parameters, QualType ReturnTy, NamedDecl *D) {
11530 if (LangOpts.NumLargeByValueCopy == 0) // No check.
11533 // Warn if the return value is pass-by-value and larger than the specified
11535 if (!ReturnTy->isDependentType() && ReturnTy.isPODType(Context)) {
11536 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity();
11537 if (Size > LangOpts.NumLargeByValueCopy)
11538 Diag(D->getLocation(), diag::warn_return_value_size)
11539 << D->getDeclName() << Size;
11542 // Warn if any parameter is pass-by-value and larger than the specified
11544 for (const ParmVarDecl *Parameter : Parameters) {
11545 QualType T = Parameter->getType();
11546 if (T->isDependentType() || !T.isPODType(Context))
11548 unsigned Size = Context.getTypeSizeInChars(T).getQuantity();
11549 if (Size > LangOpts.NumLargeByValueCopy)
11550 Diag(Parameter->getLocation(), diag::warn_parameter_size)
11551 << Parameter->getDeclName() << Size;
11555 ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc,
11556 SourceLocation NameLoc, IdentifierInfo *Name,
11557 QualType T, TypeSourceInfo *TSInfo,
11559 // In ARC, infer a lifetime qualifier for appropriate parameter types.
11560 if (getLangOpts().ObjCAutoRefCount &&
11561 T.getObjCLifetime() == Qualifiers::OCL_None &&
11562 T->isObjCLifetimeType()) {
11564 Qualifiers::ObjCLifetime lifetime;
11566 // Special cases for arrays:
11567 // - if it's const, use __unsafe_unretained
11568 // - otherwise, it's an error
11569 if (T->isArrayType()) {
11570 if (!T.isConstQualified()) {
11571 DelayedDiagnostics.add(
11572 sema::DelayedDiagnostic::makeForbiddenType(
11573 NameLoc, diag::err_arc_array_param_no_ownership, T, false));
11575 lifetime = Qualifiers::OCL_ExplicitNone;
11577 lifetime = T->getObjCARCImplicitLifetime();
11579 T = Context.getLifetimeQualifiedType(T, lifetime);
11582 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name,
11583 Context.getAdjustedParameterType(T),
11584 TSInfo, SC, nullptr);
11586 // Parameters can not be abstract class types.
11587 // For record types, this is done by the AbstractClassUsageDiagnoser once
11588 // the class has been completely parsed.
11589 if (!CurContext->isRecord() &&
11590 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl,
11591 AbstractParamType))
11592 New->setInvalidDecl();
11594 // Parameter declarators cannot be interface types. All ObjC objects are
11595 // passed by reference.
11596 if (T->isObjCObjectType()) {
11597 SourceLocation TypeEndLoc =
11598 getLocForEndOfToken(TSInfo->getTypeLoc().getLocEnd());
11600 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T
11601 << FixItHint::CreateInsertion(TypeEndLoc, "*");
11602 T = Context.getObjCObjectPointerType(T);
11606 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
11607 // duration shall not be qualified by an address-space qualifier."
11608 // Since all parameters have automatic store duration, they can not have
11609 // an address space.
11610 if (T.getAddressSpace() != 0) {
11611 // OpenCL allows function arguments declared to be an array of a type
11612 // to be qualified with an address space.
11613 if (!(getLangOpts().OpenCL && T->isArrayType())) {
11614 Diag(NameLoc, diag::err_arg_with_address_space);
11615 New->setInvalidDecl();
11622 void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
11623 SourceLocation LocAfterDecls) {
11624 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
11626 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared'
11627 // for a K&R function.
11628 if (!FTI.hasPrototype) {
11629 for (int i = FTI.NumParams; i != 0; /* decrement in loop */) {
11631 if (FTI.Params[i].Param == nullptr) {
11632 SmallString<256> Code;
11633 llvm::raw_svector_ostream(Code)
11634 << " int " << FTI.Params[i].Ident->getName() << ";\n";
11635 Diag(FTI.Params[i].IdentLoc, diag::ext_param_not_declared)
11636 << FTI.Params[i].Ident
11637 << FixItHint::CreateInsertion(LocAfterDecls, Code);
11639 // Implicitly declare the argument as type 'int' for lack of a better
11641 AttributeFactory attrs;
11642 DeclSpec DS(attrs);
11643 const char* PrevSpec; // unused
11644 unsigned DiagID; // unused
11645 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.Params[i].IdentLoc, PrevSpec,
11646 DiagID, Context.getPrintingPolicy());
11647 // Use the identifier location for the type source range.
11648 DS.SetRangeStart(FTI.Params[i].IdentLoc);
11649 DS.SetRangeEnd(FTI.Params[i].IdentLoc);
11650 Declarator ParamD(DS, Declarator::KNRTypeListContext);
11651 ParamD.SetIdentifier(FTI.Params[i].Ident, FTI.Params[i].IdentLoc);
11652 FTI.Params[i].Param = ActOnParamDeclarator(S, ParamD);
11659 Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D,
11660 MultiTemplateParamsArg TemplateParameterLists,
11661 SkipBodyInfo *SkipBody) {
11662 assert(getCurFunctionDecl() == nullptr && "Function parsing confused");
11663 assert(D.isFunctionDeclarator() && "Not a function declarator!");
11664 Scope *ParentScope = FnBodyScope->getParent();
11666 D.setFunctionDefinitionKind(FDK_Definition);
11667 Decl *DP = HandleDeclarator(ParentScope, D, TemplateParameterLists);
11668 return ActOnStartOfFunctionDef(FnBodyScope, DP, SkipBody);
11671 void Sema::ActOnFinishInlineFunctionDef(FunctionDecl *D) {
11672 Consumer.HandleInlineFunctionDefinition(D);
11675 static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD,
11676 const FunctionDecl*& PossibleZeroParamPrototype) {
11677 // Don't warn about invalid declarations.
11678 if (FD->isInvalidDecl())
11681 // Or declarations that aren't global.
11682 if (!FD->isGlobal())
11685 // Don't warn about C++ member functions.
11686 if (isa<CXXMethodDecl>(FD))
11689 // Don't warn about 'main'.
11693 // Don't warn about inline functions.
11694 if (FD->isInlined())
11697 // Don't warn about function templates.
11698 if (FD->getDescribedFunctionTemplate())
11701 // Don't warn about function template specializations.
11702 if (FD->isFunctionTemplateSpecialization())
11705 // Don't warn for OpenCL kernels.
11706 if (FD->hasAttr<OpenCLKernelAttr>())
11709 // Don't warn on explicitly deleted functions.
11710 if (FD->isDeleted())
11713 bool MissingPrototype = true;
11714 for (const FunctionDecl *Prev = FD->getPreviousDecl();
11715 Prev; Prev = Prev->getPreviousDecl()) {
11716 // Ignore any declarations that occur in function or method
11717 // scope, because they aren't visible from the header.
11718 if (Prev->getLexicalDeclContext()->isFunctionOrMethod())
11721 MissingPrototype = !Prev->getType()->isFunctionProtoType();
11722 if (FD->getNumParams() == 0)
11723 PossibleZeroParamPrototype = Prev;
11727 return MissingPrototype;
11731 Sema::CheckForFunctionRedefinition(FunctionDecl *FD,
11732 const FunctionDecl *EffectiveDefinition,
11733 SkipBodyInfo *SkipBody) {
11734 const FunctionDecl *Definition = EffectiveDefinition;
11736 if (!FD->isDefined(Definition))
11739 if (canRedefineFunction(Definition, getLangOpts()))
11742 // Don't emit an error when this is redifinition of a typo-corrected
11744 if (TypoCorrectedFunctionDefinitions.count(Definition))
11747 // If we don't have a visible definition of the function, and it's inline or
11748 // a template, skip the new definition.
11749 if (SkipBody && !hasVisibleDefinition(Definition) &&
11750 (Definition->getFormalLinkage() == InternalLinkage ||
11751 Definition->isInlined() ||
11752 Definition->getDescribedFunctionTemplate() ||
11753 Definition->getNumTemplateParameterLists())) {
11754 SkipBody->ShouldSkip = true;
11755 if (auto *TD = Definition->getDescribedFunctionTemplate())
11756 makeMergedDefinitionVisible(TD, FD->getLocation());
11757 makeMergedDefinitionVisible(const_cast<FunctionDecl*>(Definition),
11758 FD->getLocation());
11762 if (getLangOpts().GNUMode && Definition->isInlineSpecified() &&
11763 Definition->getStorageClass() == SC_Extern)
11764 Diag(FD->getLocation(), diag::err_redefinition_extern_inline)
11765 << FD->getDeclName() << getLangOpts().CPlusPlus;
11767 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName();
11769 Diag(Definition->getLocation(), diag::note_previous_definition);
11770 FD->setInvalidDecl();
11773 static void RebuildLambdaScopeInfo(CXXMethodDecl *CallOperator,
11775 CXXRecordDecl *const LambdaClass = CallOperator->getParent();
11777 LambdaScopeInfo *LSI = S.PushLambdaScope();
11778 LSI->CallOperator = CallOperator;
11779 LSI->Lambda = LambdaClass;
11780 LSI->ReturnType = CallOperator->getReturnType();
11781 const LambdaCaptureDefault LCD = LambdaClass->getLambdaCaptureDefault();
11783 if (LCD == LCD_None)
11784 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_None;
11785 else if (LCD == LCD_ByCopy)
11786 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByval;
11787 else if (LCD == LCD_ByRef)
11788 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByref;
11789 DeclarationNameInfo DNI = CallOperator->getNameInfo();
11791 LSI->IntroducerRange = DNI.getCXXOperatorNameRange();
11792 LSI->Mutable = !CallOperator->isConst();
11794 // Add the captures to the LSI so they can be noted as already
11795 // captured within tryCaptureVar.
11796 auto I = LambdaClass->field_begin();
11797 for (const auto &C : LambdaClass->captures()) {
11798 if (C.capturesVariable()) {
11799 VarDecl *VD = C.getCapturedVar();
11800 if (VD->isInitCapture())
11801 S.CurrentInstantiationScope->InstantiatedLocal(VD, VD);
11802 QualType CaptureType = VD->getType();
11803 const bool ByRef = C.getCaptureKind() == LCK_ByRef;
11804 LSI->addCapture(VD, /*IsBlock*/false, ByRef,
11805 /*RefersToEnclosingVariableOrCapture*/true, C.getLocation(),
11806 /*EllipsisLoc*/C.isPackExpansion()
11807 ? C.getEllipsisLoc() : SourceLocation(),
11808 CaptureType, /*Expr*/ nullptr);
11810 } else if (C.capturesThis()) {
11811 LSI->addThisCapture(/*Nested*/ false, C.getLocation(),
11813 C.getCaptureKind() == LCK_StarThis);
11815 LSI->addVLATypeCapture(C.getLocation(), I->getType());
11821 Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D,
11822 SkipBodyInfo *SkipBody) {
11825 FunctionDecl *FD = nullptr;
11827 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D))
11828 FD = FunTmpl->getTemplatedDecl();
11830 FD = cast<FunctionDecl>(D);
11832 // Check for defining attributes before the check for redefinition.
11833 if (const auto *Attr = FD->getAttr<AliasAttr>()) {
11834 Diag(Attr->getLocation(), diag::err_alias_is_definition) << FD << 0;
11835 FD->dropAttr<AliasAttr>();
11836 FD->setInvalidDecl();
11838 if (const auto *Attr = FD->getAttr<IFuncAttr>()) {
11839 Diag(Attr->getLocation(), diag::err_alias_is_definition) << FD << 1;
11840 FD->dropAttr<IFuncAttr>();
11841 FD->setInvalidDecl();
11844 // See if this is a redefinition.
11845 if (!FD->isLateTemplateParsed()) {
11846 CheckForFunctionRedefinition(FD, nullptr, SkipBody);
11848 // If we're skipping the body, we're done. Don't enter the scope.
11849 if (SkipBody && SkipBody->ShouldSkip)
11853 // Mark this function as "will have a body eventually". This lets users to
11854 // call e.g. isInlineDefinitionExternallyVisible while we're still parsing
11856 FD->setWillHaveBody();
11858 // If we are instantiating a generic lambda call operator, push
11859 // a LambdaScopeInfo onto the function stack. But use the information
11860 // that's already been calculated (ActOnLambdaExpr) to prime the current
11861 // LambdaScopeInfo.
11862 // When the template operator is being specialized, the LambdaScopeInfo,
11863 // has to be properly restored so that tryCaptureVariable doesn't try
11864 // and capture any new variables. In addition when calculating potential
11865 // captures during transformation of nested lambdas, it is necessary to
11866 // have the LSI properly restored.
11867 if (isGenericLambdaCallOperatorSpecialization(FD)) {
11868 assert(inTemplateInstantiation() &&
11869 "There should be an active template instantiation on the stack "
11870 "when instantiating a generic lambda!");
11871 RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this);
11873 // Enter a new function scope
11874 PushFunctionScope();
11877 // Builtin functions cannot be defined.
11878 if (unsigned BuiltinID = FD->getBuiltinID()) {
11879 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) &&
11880 !Context.BuiltinInfo.isPredefinedRuntimeFunction(BuiltinID)) {
11881 Diag(FD->getLocation(), diag::err_builtin_definition) << FD;
11882 FD->setInvalidDecl();
11886 // The return type of a function definition must be complete
11887 // (C99 6.9.1p3, C++ [dcl.fct]p6).
11888 QualType ResultType = FD->getReturnType();
11889 if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
11890 !FD->isInvalidDecl() &&
11891 RequireCompleteType(FD->getLocation(), ResultType,
11892 diag::err_func_def_incomplete_result))
11893 FD->setInvalidDecl();
11896 PushDeclContext(FnBodyScope, FD);
11898 // Check the validity of our function parameters
11899 CheckParmsForFunctionDef(FD->parameters(),
11900 /*CheckParameterNames=*/true);
11902 // Add non-parameter declarations already in the function to the current
11905 for (Decl *NPD : FD->decls()) {
11906 auto *NonParmDecl = dyn_cast<NamedDecl>(NPD);
11909 assert(!isa<ParmVarDecl>(NonParmDecl) &&
11910 "parameters should not be in newly created FD yet");
11912 // If the decl has a name, make it accessible in the current scope.
11913 if (NonParmDecl->getDeclName())
11914 PushOnScopeChains(NonParmDecl, FnBodyScope, /*AddToContext=*/false);
11916 // Similarly, dive into enums and fish their constants out, making them
11917 // accessible in this scope.
11918 if (auto *ED = dyn_cast<EnumDecl>(NonParmDecl)) {
11919 for (auto *EI : ED->enumerators())
11920 PushOnScopeChains(EI, FnBodyScope, /*AddToContext=*/false);
11925 // Introduce our parameters into the function scope
11926 for (auto Param : FD->parameters()) {
11927 Param->setOwningFunction(FD);
11929 // If this has an identifier, add it to the scope stack.
11930 if (Param->getIdentifier() && FnBodyScope) {
11931 CheckShadow(FnBodyScope, Param);
11933 PushOnScopeChains(Param, FnBodyScope);
11937 // Ensure that the function's exception specification is instantiated.
11938 if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>())
11939 ResolveExceptionSpec(D->getLocation(), FPT);
11941 // dllimport cannot be applied to non-inline function definitions.
11942 if (FD->hasAttr<DLLImportAttr>() && !FD->isInlined() &&
11943 !FD->isTemplateInstantiation()) {
11944 assert(!FD->hasAttr<DLLExportAttr>());
11945 Diag(FD->getLocation(), diag::err_attribute_dllimport_function_definition);
11946 FD->setInvalidDecl();
11949 // We want to attach documentation to original Decl (which might be
11950 // a function template).
11951 ActOnDocumentableDecl(D);
11952 if (getCurLexicalContext()->isObjCContainer() &&
11953 getCurLexicalContext()->getDeclKind() != Decl::ObjCCategoryImpl &&
11954 getCurLexicalContext()->getDeclKind() != Decl::ObjCImplementation)
11955 Diag(FD->getLocation(), diag::warn_function_def_in_objc_container);
11960 /// \brief Given the set of return statements within a function body,
11961 /// compute the variables that are subject to the named return value
11964 /// Each of the variables that is subject to the named return value
11965 /// optimization will be marked as NRVO variables in the AST, and any
11966 /// return statement that has a marked NRVO variable as its NRVO candidate can
11967 /// use the named return value optimization.
11969 /// This function applies a very simplistic algorithm for NRVO: if every return
11970 /// statement in the scope of a variable has the same NRVO candidate, that
11971 /// candidate is an NRVO variable.
11972 void Sema::computeNRVO(Stmt *Body, FunctionScopeInfo *Scope) {
11973 ReturnStmt **Returns = Scope->Returns.data();
11975 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) {
11976 if (const VarDecl *NRVOCandidate = Returns[I]->getNRVOCandidate()) {
11977 if (!NRVOCandidate->isNRVOVariable())
11978 Returns[I]->setNRVOCandidate(nullptr);
11983 bool Sema::canDelayFunctionBody(const Declarator &D) {
11984 // We can't delay parsing the body of a constexpr function template (yet).
11985 if (D.getDeclSpec().isConstexprSpecified())
11988 // We can't delay parsing the body of a function template with a deduced
11989 // return type (yet).
11990 if (D.getDeclSpec().hasAutoTypeSpec()) {
11991 // If the placeholder introduces a non-deduced trailing return type,
11992 // we can still delay parsing it.
11993 if (D.getNumTypeObjects()) {
11994 const auto &Outer = D.getTypeObject(D.getNumTypeObjects() - 1);
11995 if (Outer.Kind == DeclaratorChunk::Function &&
11996 Outer.Fun.hasTrailingReturnType()) {
11997 QualType Ty = GetTypeFromParser(Outer.Fun.getTrailingReturnType());
11998 return Ty.isNull() || !Ty->isUndeducedType();
12007 bool Sema::canSkipFunctionBody(Decl *D) {
12008 // We cannot skip the body of a function (or function template) which is
12009 // constexpr, since we may need to evaluate its body in order to parse the
12010 // rest of the file.
12011 // We cannot skip the body of a function with an undeduced return type,
12012 // because any callers of that function need to know the type.
12013 if (const FunctionDecl *FD = D->getAsFunction())
12014 if (FD->isConstexpr() || FD->getReturnType()->isUndeducedType())
12016 return Consumer.shouldSkipFunctionBody(D);
12019 Decl *Sema::ActOnSkippedFunctionBody(Decl *Decl) {
12020 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Decl))
12021 FD->setHasSkippedBody();
12022 else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(Decl))
12023 MD->setHasSkippedBody();
12027 Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) {
12028 return ActOnFinishFunctionBody(D, BodyArg, false);
12031 Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
12032 bool IsInstantiation) {
12033 FunctionDecl *FD = dcl ? dcl->getAsFunction() : nullptr;
12035 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
12036 sema::AnalysisBasedWarnings::Policy *ActivePolicy = nullptr;
12038 if (getLangOpts().CoroutinesTS && getCurFunction()->CoroutinePromise)
12039 CheckCompletedCoroutineBody(FD, Body);
12044 if (getLangOpts().CPlusPlus14) {
12045 if (!FD->isInvalidDecl() && Body && !FD->isDependentContext() &&
12046 FD->getReturnType()->isUndeducedType()) {
12047 // If the function has a deduced result type but contains no 'return'
12048 // statements, the result type as written must be exactly 'auto', and
12049 // the deduced result type is 'void'.
12050 if (!FD->getReturnType()->getAs<AutoType>()) {
12051 Diag(dcl->getLocation(), diag::err_auto_fn_no_return_but_not_auto)
12052 << FD->getReturnType();
12053 FD->setInvalidDecl();
12055 // Substitute 'void' for the 'auto' in the type.
12056 TypeLoc ResultType = getReturnTypeLoc(FD);
12057 Context.adjustDeducedFunctionResultType(
12058 FD, SubstAutoType(ResultType.getType(), Context.VoidTy));
12061 } else if (getLangOpts().CPlusPlus11 && isLambdaCallOperator(FD)) {
12062 // In C++11, we don't use 'auto' deduction rules for lambda call
12063 // operators because we don't support return type deduction.
12064 auto *LSI = getCurLambda();
12065 if (LSI->HasImplicitReturnType) {
12066 deduceClosureReturnType(*LSI);
12068 // C++11 [expr.prim.lambda]p4:
12069 // [...] if there are no return statements in the compound-statement
12070 // [the deduced type is] the type void
12072 LSI->ReturnType.isNull() ? Context.VoidTy : LSI->ReturnType;
12074 // Update the return type to the deduced type.
12075 const FunctionProtoType *Proto =
12076 FD->getType()->getAs<FunctionProtoType>();
12077 FD->setType(Context.getFunctionType(RetType, Proto->getParamTypes(),
12078 Proto->getExtProtoInfo()));
12082 // The only way to be included in UndefinedButUsed is if there is an
12083 // ODR use before the definition. Avoid the expensive map lookup if this
12084 // is the first declaration.
12085 if (!FD->isFirstDecl() && FD->getPreviousDecl()->isUsed()) {
12086 if (!FD->isExternallyVisible())
12087 UndefinedButUsed.erase(FD);
12088 else if (FD->isInlined() &&
12089 !LangOpts.GNUInline &&
12090 (!FD->getPreviousDecl()->hasAttr<GNUInlineAttr>()))
12091 UndefinedButUsed.erase(FD);
12094 // If the function implicitly returns zero (like 'main') or is naked,
12095 // don't complain about missing return statements.
12096 if (FD->hasImplicitReturnZero() || FD->hasAttr<NakedAttr>())
12097 WP.disableCheckFallThrough();
12099 // MSVC permits the use of pure specifier (=0) on function definition,
12100 // defined at class scope, warn about this non-standard construct.
12101 if (getLangOpts().MicrosoftExt && FD->isPure() && FD->isCanonicalDecl())
12102 Diag(FD->getLocation(), diag::ext_pure_function_definition);
12104 if (!FD->isInvalidDecl()) {
12105 // Don't diagnose unused parameters of defaulted or deleted functions.
12106 if (!FD->isDeleted() && !FD->isDefaulted())
12107 DiagnoseUnusedParameters(FD->parameters());
12108 DiagnoseSizeOfParametersAndReturnValue(FD->parameters(),
12109 FD->getReturnType(), FD);
12111 // If this is a structor, we need a vtable.
12112 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD))
12113 MarkVTableUsed(FD->getLocation(), Constructor->getParent());
12114 else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(FD))
12115 MarkVTableUsed(FD->getLocation(), Destructor->getParent());
12117 // Try to apply the named return value optimization. We have to check
12118 // if we can do this here because lambdas keep return statements around
12119 // to deduce an implicit return type.
12120 if (getLangOpts().CPlusPlus && FD->getReturnType()->isRecordType() &&
12121 !FD->isDependentContext())
12122 computeNRVO(Body, getCurFunction());
12125 // GNU warning -Wmissing-prototypes:
12126 // Warn if a global function is defined without a previous
12127 // prototype declaration. This warning is issued even if the
12128 // definition itself provides a prototype. The aim is to detect
12129 // global functions that fail to be declared in header files.
12130 const FunctionDecl *PossibleZeroParamPrototype = nullptr;
12131 if (ShouldWarnAboutMissingPrototype(FD, PossibleZeroParamPrototype)) {
12132 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD;
12134 if (PossibleZeroParamPrototype) {
12135 // We found a declaration that is not a prototype,
12136 // but that could be a zero-parameter prototype
12137 if (TypeSourceInfo *TI =
12138 PossibleZeroParamPrototype->getTypeSourceInfo()) {
12139 TypeLoc TL = TI->getTypeLoc();
12140 if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>())
12141 Diag(PossibleZeroParamPrototype->getLocation(),
12142 diag::note_declaration_not_a_prototype)
12143 << PossibleZeroParamPrototype
12144 << FixItHint::CreateInsertion(FTL.getRParenLoc(), "void");
12148 // GNU warning -Wstrict-prototypes
12149 // Warn if K&R function is defined without a previous declaration.
12150 // This warning is issued only if the definition itself does not provide
12151 // a prototype. Only K&R definitions do not provide a prototype.
12152 // An empty list in a function declarator that is part of a definition
12153 // of that function specifies that the function has no parameters
12154 // (C99 6.7.5.3p14)
12155 if (!FD->hasWrittenPrototype() && FD->getNumParams() > 0 &&
12156 !LangOpts.CPlusPlus) {
12157 TypeSourceInfo *TI = FD->getTypeSourceInfo();
12158 TypeLoc TL = TI->getTypeLoc();
12159 FunctionTypeLoc FTL = TL.getAsAdjusted<FunctionTypeLoc>();
12160 Diag(FTL.getLParenLoc(), diag::warn_strict_prototypes) << 1;
12164 if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) {
12165 const CXXMethodDecl *KeyFunction;
12166 if (MD->isOutOfLine() && (MD = MD->getCanonicalDecl()) &&
12168 (KeyFunction = Context.getCurrentKeyFunction(MD->getParent())) &&
12169 MD == KeyFunction->getCanonicalDecl()) {
12170 // Update the key-function state if necessary for this ABI.
12171 if (FD->isInlined() &&
12172 !Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
12173 Context.setNonKeyFunction(MD);
12175 // If the newly-chosen key function is already defined, then we
12176 // need to mark the vtable as used retroactively.
12177 KeyFunction = Context.getCurrentKeyFunction(MD->getParent());
12178 const FunctionDecl *Definition;
12179 if (KeyFunction && KeyFunction->isDefined(Definition))
12180 MarkVTableUsed(Definition->getLocation(), MD->getParent(), true);
12182 // We just defined they key function; mark the vtable as used.
12183 MarkVTableUsed(FD->getLocation(), MD->getParent(), true);
12188 assert((FD == getCurFunctionDecl() || getCurLambda()->CallOperator == FD) &&
12189 "Function parsing confused");
12190 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) {
12191 assert(MD == getCurMethodDecl() && "Method parsing confused");
12193 if (!MD->isInvalidDecl()) {
12194 DiagnoseUnusedParameters(MD->parameters());
12195 DiagnoseSizeOfParametersAndReturnValue(MD->parameters(),
12196 MD->getReturnType(), MD);
12199 computeNRVO(Body, getCurFunction());
12201 if (getCurFunction()->ObjCShouldCallSuper) {
12202 Diag(MD->getLocEnd(), diag::warn_objc_missing_super_call)
12203 << MD->getSelector().getAsString();
12204 getCurFunction()->ObjCShouldCallSuper = false;
12206 if (getCurFunction()->ObjCWarnForNoDesignatedInitChain) {
12207 const ObjCMethodDecl *InitMethod = nullptr;
12208 bool isDesignated =
12209 MD->isDesignatedInitializerForTheInterface(&InitMethod);
12210 assert(isDesignated && InitMethod);
12211 (void)isDesignated;
12213 auto superIsNSObject = [&](const ObjCMethodDecl *MD) {
12214 auto IFace = MD->getClassInterface();
12217 auto SuperD = IFace->getSuperClass();
12220 return SuperD->getIdentifier() ==
12221 NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject);
12223 // Don't issue this warning for unavailable inits or direct subclasses
12225 if (!MD->isUnavailable() && !superIsNSObject(MD)) {
12226 Diag(MD->getLocation(),
12227 diag::warn_objc_designated_init_missing_super_call);
12228 Diag(InitMethod->getLocation(),
12229 diag::note_objc_designated_init_marked_here);
12231 getCurFunction()->ObjCWarnForNoDesignatedInitChain = false;
12233 if (getCurFunction()->ObjCWarnForNoInitDelegation) {
12234 // Don't issue this warning for unavaialable inits.
12235 if (!MD->isUnavailable())
12236 Diag(MD->getLocation(),
12237 diag::warn_objc_secondary_init_missing_init_call);
12238 getCurFunction()->ObjCWarnForNoInitDelegation = false;
12244 if (Body && getCurFunction()->HasPotentialAvailabilityViolations)
12245 DiagnoseUnguardedAvailabilityViolations(dcl);
12247 assert(!getCurFunction()->ObjCShouldCallSuper &&
12248 "This should only be set for ObjC methods, which should have been "
12249 "handled in the block above.");
12251 // Verify and clean out per-function state.
12252 if (Body && (!FD || !FD->isDefaulted())) {
12253 // C++ constructors that have function-try-blocks can't have return
12254 // statements in the handlers of that block. (C++ [except.handle]p14)
12256 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body))
12257 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body));
12259 // Verify that gotos and switch cases don't jump into scopes illegally.
12260 if (getCurFunction()->NeedsScopeChecking() &&
12261 !PP.isCodeCompletionEnabled())
12262 DiagnoseInvalidJumps(Body);
12264 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) {
12265 if (!Destructor->getParent()->isDependentType())
12266 CheckDestructor(Destructor);
12268 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
12269 Destructor->getParent());
12272 // If any errors have occurred, clear out any temporaries that may have
12273 // been leftover. This ensures that these temporaries won't be picked up for
12274 // deletion in some later function.
12275 if (getDiagnostics().hasErrorOccurred() ||
12276 getDiagnostics().getSuppressAllDiagnostics()) {
12277 DiscardCleanupsInEvaluationContext();
12279 if (!getDiagnostics().hasUncompilableErrorOccurred() &&
12280 !isa<FunctionTemplateDecl>(dcl)) {
12281 // Since the body is valid, issue any analysis-based warnings that are
12283 ActivePolicy = &WP;
12286 if (!IsInstantiation && FD && FD->isConstexpr() && !FD->isInvalidDecl() &&
12287 (!CheckConstexprFunctionDecl(FD) ||
12288 !CheckConstexprFunctionBody(FD, Body)))
12289 FD->setInvalidDecl();
12291 if (FD && FD->hasAttr<NakedAttr>()) {
12292 for (const Stmt *S : Body->children()) {
12293 // Allow local register variables without initializer as they don't
12294 // require prologue.
12295 bool RegisterVariables = false;
12296 if (auto *DS = dyn_cast<DeclStmt>(S)) {
12297 for (const auto *Decl : DS->decls()) {
12298 if (const auto *Var = dyn_cast<VarDecl>(Decl)) {
12299 RegisterVariables =
12300 Var->hasAttr<AsmLabelAttr>() && !Var->hasInit();
12301 if (!RegisterVariables)
12306 if (RegisterVariables)
12308 if (!isa<AsmStmt>(S) && !isa<NullStmt>(S)) {
12309 Diag(S->getLocStart(), diag::err_non_asm_stmt_in_naked_function);
12310 Diag(FD->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
12311 FD->setInvalidDecl();
12317 assert(ExprCleanupObjects.size() ==
12318 ExprEvalContexts.back().NumCleanupObjects &&
12319 "Leftover temporaries in function");
12320 assert(!Cleanup.exprNeedsCleanups() && "Unaccounted cleanups in function");
12321 assert(MaybeODRUseExprs.empty() &&
12322 "Leftover expressions for odr-use checking");
12325 if (!IsInstantiation)
12328 PopFunctionScopeInfo(ActivePolicy, dcl);
12329 // If any errors have occurred, clear out any temporaries that may have
12330 // been leftover. This ensures that these temporaries won't be picked up for
12331 // deletion in some later function.
12332 if (getDiagnostics().hasErrorOccurred()) {
12333 DiscardCleanupsInEvaluationContext();
12339 /// When we finish delayed parsing of an attribute, we must attach it to the
12341 void Sema::ActOnFinishDelayedAttribute(Scope *S, Decl *D,
12342 ParsedAttributes &Attrs) {
12343 // Always attach attributes to the underlying decl.
12344 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
12345 D = TD->getTemplatedDecl();
12346 ProcessDeclAttributeList(S, D, Attrs.getList());
12348 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(D))
12349 if (Method->isStatic())
12350 checkThisInStaticMemberFunctionAttributes(Method);
12353 /// ImplicitlyDefineFunction - An undeclared identifier was used in a function
12354 /// call, forming a call to an implicitly defined function (per C99 6.5.1p2).
12355 NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
12356 IdentifierInfo &II, Scope *S) {
12357 // Before we produce a declaration for an implicitly defined
12358 // function, see whether there was a locally-scoped declaration of
12359 // this name as a function or variable. If so, use that
12360 // (non-visible) declaration, and complain about it.
12361 if (NamedDecl *ExternCPrev = findLocallyScopedExternCDecl(&II)) {
12362 Diag(Loc, diag::warn_use_out_of_scope_declaration) << ExternCPrev;
12363 Diag(ExternCPrev->getLocation(), diag::note_previous_declaration);
12364 return ExternCPrev;
12367 // Extension in C99. Legal in C90, but warn about it.
12369 if (II.getName().startswith("__builtin_"))
12370 diag_id = diag::warn_builtin_unknown;
12371 else if (getLangOpts().C99)
12372 diag_id = diag::ext_implicit_function_decl;
12374 diag_id = diag::warn_implicit_function_decl;
12375 Diag(Loc, diag_id) << &II;
12377 // Because typo correction is expensive, only do it if the implicit
12378 // function declaration is going to be treated as an error.
12379 if (Diags.getDiagnosticLevel(diag_id, Loc) >= DiagnosticsEngine::Error) {
12380 TypoCorrection Corrected;
12382 (Corrected = CorrectTypo(
12383 DeclarationNameInfo(&II, Loc), LookupOrdinaryName, S, nullptr,
12384 llvm::make_unique<DeclFilterCCC<FunctionDecl>>(), CTK_NonError)))
12385 diagnoseTypo(Corrected, PDiag(diag::note_function_suggestion),
12386 /*ErrorRecovery*/false);
12389 // Set a Declarator for the implicit definition: int foo();
12391 AttributeFactory attrFactory;
12392 DeclSpec DS(attrFactory);
12394 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID,
12395 Context.getPrintingPolicy());
12396 (void)Error; // Silence warning.
12397 assert(!Error && "Error setting up implicit decl!");
12398 SourceLocation NoLoc;
12399 Declarator D(DS, Declarator::BlockContext);
12400 D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false,
12401 /*IsAmbiguous=*/false,
12402 /*LParenLoc=*/NoLoc,
12403 /*Params=*/nullptr,
12405 /*EllipsisLoc=*/NoLoc,
12406 /*RParenLoc=*/NoLoc,
12408 /*RefQualifierIsLvalueRef=*/true,
12409 /*RefQualifierLoc=*/NoLoc,
12410 /*ConstQualifierLoc=*/NoLoc,
12411 /*VolatileQualifierLoc=*/NoLoc,
12412 /*RestrictQualifierLoc=*/NoLoc,
12413 /*MutableLoc=*/NoLoc,
12415 /*ESpecRange=*/SourceRange(),
12416 /*Exceptions=*/nullptr,
12417 /*ExceptionRanges=*/nullptr,
12418 /*NumExceptions=*/0,
12419 /*NoexceptExpr=*/nullptr,
12420 /*ExceptionSpecTokens=*/nullptr,
12421 /*DeclsInPrototype=*/None,
12423 DS.getAttributes(),
12425 D.SetIdentifier(&II, Loc);
12427 // Insert this function into translation-unit scope.
12429 DeclContext *PrevDC = CurContext;
12430 CurContext = Context.getTranslationUnitDecl();
12432 FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(TUScope, D));
12435 CurContext = PrevDC;
12437 AddKnownFunctionAttributes(FD);
12442 /// \brief Adds any function attributes that we know a priori based on
12443 /// the declaration of this function.
12445 /// These attributes can apply both to implicitly-declared builtins
12446 /// (like __builtin___printf_chk) or to library-declared functions
12447 /// like NSLog or printf.
12449 /// We need to check for duplicate attributes both here and where user-written
12450 /// attributes are applied to declarations.
12451 void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) {
12452 if (FD->isInvalidDecl())
12455 // If this is a built-in function, map its builtin attributes to
12456 // actual attributes.
12457 if (unsigned BuiltinID = FD->getBuiltinID()) {
12458 // Handle printf-formatting attributes.
12459 unsigned FormatIdx;
12461 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) {
12462 if (!FD->hasAttr<FormatAttr>()) {
12463 const char *fmt = "printf";
12464 unsigned int NumParams = FD->getNumParams();
12465 if (FormatIdx < NumParams && // NumParams may be 0 (e.g. vfprintf)
12466 FD->getParamDecl(FormatIdx)->getType()->isObjCObjectPointerType())
12468 FD->addAttr(FormatAttr::CreateImplicit(Context,
12469 &Context.Idents.get(fmt),
12471 HasVAListArg ? 0 : FormatIdx+2,
12472 FD->getLocation()));
12475 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx,
12477 if (!FD->hasAttr<FormatAttr>())
12478 FD->addAttr(FormatAttr::CreateImplicit(Context,
12479 &Context.Idents.get("scanf"),
12481 HasVAListArg ? 0 : FormatIdx+2,
12482 FD->getLocation()));
12485 // Mark const if we don't care about errno and that is the only
12486 // thing preventing the function from being const. This allows
12487 // IRgen to use LLVM intrinsics for such functions.
12488 if (!getLangOpts().MathErrno &&
12489 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) {
12490 if (!FD->hasAttr<ConstAttr>())
12491 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
12494 if (Context.BuiltinInfo.isReturnsTwice(BuiltinID) &&
12495 !FD->hasAttr<ReturnsTwiceAttr>())
12496 FD->addAttr(ReturnsTwiceAttr::CreateImplicit(Context,
12497 FD->getLocation()));
12498 if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->hasAttr<NoThrowAttr>())
12499 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
12500 if (Context.BuiltinInfo.isPure(BuiltinID) && !FD->hasAttr<PureAttr>())
12501 FD->addAttr(PureAttr::CreateImplicit(Context, FD->getLocation()));
12502 if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->hasAttr<ConstAttr>())
12503 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
12504 if (getLangOpts().CUDA && Context.BuiltinInfo.isTSBuiltin(BuiltinID) &&
12505 !FD->hasAttr<CUDADeviceAttr>() && !FD->hasAttr<CUDAHostAttr>()) {
12506 // Add the appropriate attribute, depending on the CUDA compilation mode
12507 // and which target the builtin belongs to. For example, during host
12508 // compilation, aux builtins are __device__, while the rest are __host__.
12509 if (getLangOpts().CUDAIsDevice !=
12510 Context.BuiltinInfo.isAuxBuiltinID(BuiltinID))
12511 FD->addAttr(CUDADeviceAttr::CreateImplicit(Context, FD->getLocation()));
12513 FD->addAttr(CUDAHostAttr::CreateImplicit(Context, FD->getLocation()));
12517 // If C++ exceptions are enabled but we are told extern "C" functions cannot
12518 // throw, add an implicit nothrow attribute to any extern "C" function we come
12520 if (getLangOpts().CXXExceptions && getLangOpts().ExternCNoUnwind &&
12521 FD->isExternC() && !FD->hasAttr<NoThrowAttr>()) {
12522 const auto *FPT = FD->getType()->getAs<FunctionProtoType>();
12523 if (!FPT || FPT->getExceptionSpecType() == EST_None)
12524 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
12527 IdentifierInfo *Name = FD->getIdentifier();
12530 if ((!getLangOpts().CPlusPlus &&
12531 FD->getDeclContext()->isTranslationUnit()) ||
12532 (isa<LinkageSpecDecl>(FD->getDeclContext()) &&
12533 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() ==
12534 LinkageSpecDecl::lang_c)) {
12535 // Okay: this could be a libc/libm/Objective-C function we know
12540 if (Name->isStr("asprintf") || Name->isStr("vasprintf")) {
12541 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be
12542 // target-specific builtins, perhaps?
12543 if (!FD->hasAttr<FormatAttr>())
12544 FD->addAttr(FormatAttr::CreateImplicit(Context,
12545 &Context.Idents.get("printf"), 2,
12546 Name->isStr("vasprintf") ? 0 : 3,
12547 FD->getLocation()));
12550 if (Name->isStr("__CFStringMakeConstantString")) {
12551 // We already have a __builtin___CFStringMakeConstantString,
12552 // but builds that use -fno-constant-cfstrings don't go through that.
12553 if (!FD->hasAttr<FormatArgAttr>())
12554 FD->addAttr(FormatArgAttr::CreateImplicit(Context, 1,
12555 FD->getLocation()));
12559 TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
12560 TypeSourceInfo *TInfo) {
12561 assert(D.getIdentifier() && "Wrong callback for declspec without declarator");
12562 assert(!T.isNull() && "GetTypeForDeclarator() returned null type");
12565 assert(D.isInvalidType() && "no declarator info for valid type");
12566 TInfo = Context.getTrivialTypeSourceInfo(T);
12569 // Scope manipulation handled by caller.
12570 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext,
12572 D.getIdentifierLoc(),
12576 // Bail out immediately if we have an invalid declaration.
12577 if (D.isInvalidType()) {
12578 NewTD->setInvalidDecl();
12582 if (D.getDeclSpec().isModulePrivateSpecified()) {
12583 if (CurContext->isFunctionOrMethod())
12584 Diag(NewTD->getLocation(), diag::err_module_private_local)
12585 << 2 << NewTD->getDeclName()
12586 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
12587 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
12589 NewTD->setModulePrivate();
12592 // C++ [dcl.typedef]p8:
12593 // If the typedef declaration defines an unnamed class (or
12594 // enum), the first typedef-name declared by the declaration
12595 // to be that class type (or enum type) is used to denote the
12596 // class type (or enum type) for linkage purposes only.
12597 // We need to check whether the type was declared in the declaration.
12598 switch (D.getDeclSpec().getTypeSpecType()) {
12601 case TST_interface:
12604 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
12605 setTagNameForLinkagePurposes(tagFromDeclSpec, NewTD);
12616 /// \brief Check that this is a valid underlying type for an enum declaration.
12617 bool Sema::CheckEnumUnderlyingType(TypeSourceInfo *TI) {
12618 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
12619 QualType T = TI->getType();
12621 if (T->isDependentType())
12624 if (const BuiltinType *BT = T->getAs<BuiltinType>())
12625 if (BT->isInteger())
12628 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) << T;
12632 /// Check whether this is a valid redeclaration of a previous enumeration.
12633 /// \return true if the redeclaration was invalid.
12634 bool Sema::CheckEnumRedeclaration(
12635 SourceLocation EnumLoc, bool IsScoped, QualType EnumUnderlyingTy,
12636 bool EnumUnderlyingIsImplicit, const EnumDecl *Prev) {
12637 bool IsFixed = !EnumUnderlyingTy.isNull();
12639 if (IsScoped != Prev->isScoped()) {
12640 Diag(EnumLoc, diag::err_enum_redeclare_scoped_mismatch)
12641 << Prev->isScoped();
12642 Diag(Prev->getLocation(), diag::note_previous_declaration);
12646 if (IsFixed && Prev->isFixed()) {
12647 if (!EnumUnderlyingTy->isDependentType() &&
12648 !Prev->getIntegerType()->isDependentType() &&
12649 !Context.hasSameUnqualifiedType(EnumUnderlyingTy,
12650 Prev->getIntegerType())) {
12651 // TODO: Highlight the underlying type of the redeclaration.
12652 Diag(EnumLoc, diag::err_enum_redeclare_type_mismatch)
12653 << EnumUnderlyingTy << Prev->getIntegerType();
12654 Diag(Prev->getLocation(), diag::note_previous_declaration)
12655 << Prev->getIntegerTypeRange();
12658 } else if (IsFixed && !Prev->isFixed() && EnumUnderlyingIsImplicit) {
12660 } else if (!IsFixed && Prev->isFixed() && !Prev->getIntegerTypeSourceInfo()) {
12662 } else if (IsFixed != Prev->isFixed()) {
12663 Diag(EnumLoc, diag::err_enum_redeclare_fixed_mismatch)
12664 << Prev->isFixed();
12665 Diag(Prev->getLocation(), diag::note_previous_declaration);
12672 /// \brief Get diagnostic %select index for tag kind for
12673 /// redeclaration diagnostic message.
12674 /// WARNING: Indexes apply to particular diagnostics only!
12676 /// \returns diagnostic %select index.
12677 static unsigned getRedeclDiagFromTagKind(TagTypeKind Tag) {
12679 case TTK_Struct: return 0;
12680 case TTK_Interface: return 1;
12681 case TTK_Class: return 2;
12682 default: llvm_unreachable("Invalid tag kind for redecl diagnostic!");
12686 /// \brief Determine if tag kind is a class-key compatible with
12687 /// class for redeclaration (class, struct, or __interface).
12689 /// \returns true iff the tag kind is compatible.
12690 static bool isClassCompatTagKind(TagTypeKind Tag)
12692 return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface;
12695 Sema::NonTagKind Sema::getNonTagTypeDeclKind(const Decl *PrevDecl,
12697 if (isa<TypedefDecl>(PrevDecl))
12698 return NTK_Typedef;
12699 else if (isa<TypeAliasDecl>(PrevDecl))
12700 return NTK_TypeAlias;
12701 else if (isa<ClassTemplateDecl>(PrevDecl))
12702 return NTK_Template;
12703 else if (isa<TypeAliasTemplateDecl>(PrevDecl))
12704 return NTK_TypeAliasTemplate;
12705 else if (isa<TemplateTemplateParmDecl>(PrevDecl))
12706 return NTK_TemplateTemplateArgument;
12709 case TTK_Interface:
12711 return getLangOpts().CPlusPlus ? NTK_NonClass : NTK_NonStruct;
12713 return NTK_NonUnion;
12715 return NTK_NonEnum;
12717 llvm_unreachable("invalid TTK");
12720 /// \brief Determine whether a tag with a given kind is acceptable
12721 /// as a redeclaration of the given tag declaration.
12723 /// \returns true if the new tag kind is acceptable, false otherwise.
12724 bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous,
12725 TagTypeKind NewTag, bool isDefinition,
12726 SourceLocation NewTagLoc,
12727 const IdentifierInfo *Name) {
12728 // C++ [dcl.type.elab]p3:
12729 // The class-key or enum keyword present in the
12730 // elaborated-type-specifier shall agree in kind with the
12731 // declaration to which the name in the elaborated-type-specifier
12732 // refers. This rule also applies to the form of
12733 // elaborated-type-specifier that declares a class-name or
12734 // friend class since it can be construed as referring to the
12735 // definition of the class. Thus, in any
12736 // elaborated-type-specifier, the enum keyword shall be used to
12737 // refer to an enumeration (7.2), the union class-key shall be
12738 // used to refer to a union (clause 9), and either the class or
12739 // struct class-key shall be used to refer to a class (clause 9)
12740 // declared using the class or struct class-key.
12741 TagTypeKind OldTag = Previous->getTagKind();
12742 if (!isDefinition || !isClassCompatTagKind(NewTag))
12743 if (OldTag == NewTag)
12746 if (isClassCompatTagKind(OldTag) && isClassCompatTagKind(NewTag)) {
12747 // Warn about the struct/class tag mismatch.
12748 bool isTemplate = false;
12749 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous))
12750 isTemplate = Record->getDescribedClassTemplate();
12752 if (inTemplateInstantiation()) {
12753 // In a template instantiation, do not offer fix-its for tag mismatches
12754 // since they usually mess up the template instead of fixing the problem.
12755 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
12756 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12757 << getRedeclDiagFromTagKind(OldTag);
12761 if (isDefinition) {
12762 // On definitions, check previous tags and issue a fix-it for each
12763 // one that doesn't match the current tag.
12764 if (Previous->getDefinition()) {
12765 // Don't suggest fix-its for redefinitions.
12769 bool previousMismatch = false;
12770 for (auto I : Previous->redecls()) {
12771 if (I->getTagKind() != NewTag) {
12772 if (!previousMismatch) {
12773 previousMismatch = true;
12774 Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch)
12775 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12776 << getRedeclDiagFromTagKind(I->getTagKind());
12778 Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion)
12779 << getRedeclDiagFromTagKind(NewTag)
12780 << FixItHint::CreateReplacement(I->getInnerLocStart(),
12781 TypeWithKeyword::getTagTypeKindName(NewTag));
12787 // Check for a previous definition. If current tag and definition
12788 // are same type, do nothing. If no definition, but disagree with
12789 // with previous tag type, give a warning, but no fix-it.
12790 const TagDecl *Redecl = Previous->getDefinition() ?
12791 Previous->getDefinition() : Previous;
12792 if (Redecl->getTagKind() == NewTag) {
12796 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
12797 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12798 << getRedeclDiagFromTagKind(OldTag);
12799 Diag(Redecl->getLocation(), diag::note_previous_use);
12801 // If there is a previous definition, suggest a fix-it.
12802 if (Previous->getDefinition()) {
12803 Diag(NewTagLoc, diag::note_struct_class_suggestion)
12804 << getRedeclDiagFromTagKind(Redecl->getTagKind())
12805 << FixItHint::CreateReplacement(SourceRange(NewTagLoc),
12806 TypeWithKeyword::getTagTypeKindName(Redecl->getTagKind()));
12814 /// Add a minimal nested name specifier fixit hint to allow lookup of a tag name
12815 /// from an outer enclosing namespace or file scope inside a friend declaration.
12816 /// This should provide the commented out code in the following snippet:
12820 /// struct Y { friend struct /*N::*/ X; };
12823 static FixItHint createFriendTagNNSFixIt(Sema &SemaRef, NamedDecl *ND, Scope *S,
12824 SourceLocation NameLoc) {
12825 // While the decl is in a namespace, do repeated lookup of that name and see
12826 // if we get the same namespace back. If we do not, continue until
12827 // translation unit scope, at which point we have a fully qualified NNS.
12828 SmallVector<IdentifierInfo *, 4> Namespaces;
12829 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
12830 for (; !DC->isTranslationUnit(); DC = DC->getParent()) {
12831 // This tag should be declared in a namespace, which can only be enclosed by
12832 // other namespaces. Bail if there's an anonymous namespace in the chain.
12833 NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(DC);
12834 if (!Namespace || Namespace->isAnonymousNamespace())
12835 return FixItHint();
12836 IdentifierInfo *II = Namespace->getIdentifier();
12837 Namespaces.push_back(II);
12838 NamedDecl *Lookup = SemaRef.LookupSingleName(
12839 S, II, NameLoc, Sema::LookupNestedNameSpecifierName);
12840 if (Lookup == Namespace)
12844 // Once we have all the namespaces, reverse them to go outermost first, and
12846 SmallString<64> Insertion;
12847 llvm::raw_svector_ostream OS(Insertion);
12848 if (DC->isTranslationUnit())
12850 std::reverse(Namespaces.begin(), Namespaces.end());
12851 for (auto *II : Namespaces)
12852 OS << II->getName() << "::";
12853 return FixItHint::CreateInsertion(NameLoc, Insertion);
12856 /// \brief Determine whether a tag originally declared in context \p OldDC can
12857 /// be redeclared with an unqualfied name in \p NewDC (assuming name lookup
12858 /// found a declaration in \p OldDC as a previous decl, perhaps through a
12859 /// using-declaration).
12860 static bool isAcceptableTagRedeclContext(Sema &S, DeclContext *OldDC,
12861 DeclContext *NewDC) {
12862 OldDC = OldDC->getRedeclContext();
12863 NewDC = NewDC->getRedeclContext();
12865 if (OldDC->Equals(NewDC))
12868 // In MSVC mode, we allow a redeclaration if the contexts are related (either
12869 // encloses the other).
12870 if (S.getLangOpts().MSVCCompat &&
12871 (OldDC->Encloses(NewDC) || NewDC->Encloses(OldDC)))
12877 /// \brief This is invoked when we see 'struct foo' or 'struct {'. In the
12878 /// former case, Name will be non-null. In the later case, Name will be null.
12879 /// TagSpec indicates what kind of tag this is. TUK indicates whether this is a
12880 /// reference/declaration/definition of a tag.
12882 /// \param IsTypeSpecifier \c true if this is a type-specifier (or
12883 /// trailing-type-specifier) other than one in an alias-declaration.
12885 /// \param SkipBody If non-null, will be set to indicate if the caller should
12886 /// skip the definition of this tag and treat it as if it were a declaration.
12887 Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
12888 SourceLocation KWLoc, CXXScopeSpec &SS,
12889 IdentifierInfo *Name, SourceLocation NameLoc,
12890 AttributeList *Attr, AccessSpecifier AS,
12891 SourceLocation ModulePrivateLoc,
12892 MultiTemplateParamsArg TemplateParameterLists,
12893 bool &OwnedDecl, bool &IsDependent,
12894 SourceLocation ScopedEnumKWLoc,
12895 bool ScopedEnumUsesClassTag,
12896 TypeResult UnderlyingType,
12897 bool IsTypeSpecifier, SkipBodyInfo *SkipBody) {
12898 // If this is not a definition, it must have a name.
12899 IdentifierInfo *OrigName = Name;
12900 assert((Name != nullptr || TUK == TUK_Definition) &&
12901 "Nameless record must be a definition!");
12902 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference);
12905 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
12906 bool ScopedEnum = ScopedEnumKWLoc.isValid();
12908 // FIXME: Check member specializations more carefully.
12909 bool isMemberSpecialization = false;
12910 bool Invalid = false;
12912 // We only need to do this matching if we have template parameters
12913 // or a scope specifier, which also conveniently avoids this work
12914 // for non-C++ cases.
12915 if (TemplateParameterLists.size() > 0 ||
12916 (SS.isNotEmpty() && TUK != TUK_Reference)) {
12917 if (TemplateParameterList *TemplateParams =
12918 MatchTemplateParametersToScopeSpecifier(
12919 KWLoc, NameLoc, SS, nullptr, TemplateParameterLists,
12920 TUK == TUK_Friend, isMemberSpecialization, Invalid)) {
12921 if (Kind == TTK_Enum) {
12922 Diag(KWLoc, diag::err_enum_template);
12926 if (TemplateParams->size() > 0) {
12927 // This is a declaration or definition of a class template (which may
12928 // be a member of another template).
12934 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc,
12935 SS, Name, NameLoc, Attr,
12936 TemplateParams, AS,
12938 /*FriendLoc*/SourceLocation(),
12939 TemplateParameterLists.size()-1,
12940 TemplateParameterLists.data(),
12942 return Result.get();
12944 // The "template<>" header is extraneous.
12945 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
12946 << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
12947 isMemberSpecialization = true;
12952 // Figure out the underlying type if this a enum declaration. We need to do
12953 // this early, because it's needed to detect if this is an incompatible
12955 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying;
12956 bool EnumUnderlyingIsImplicit = false;
12958 if (Kind == TTK_Enum) {
12959 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum))
12960 // No underlying type explicitly specified, or we failed to parse the
12961 // type, default to int.
12962 EnumUnderlying = Context.IntTy.getTypePtr();
12963 else if (UnderlyingType.get()) {
12964 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
12965 // integral type; any cv-qualification is ignored.
12966 TypeSourceInfo *TI = nullptr;
12967 GetTypeFromParser(UnderlyingType.get(), &TI);
12968 EnumUnderlying = TI;
12970 if (CheckEnumUnderlyingType(TI))
12971 // Recover by falling back to int.
12972 EnumUnderlying = Context.IntTy.getTypePtr();
12974 if (DiagnoseUnexpandedParameterPack(TI->getTypeLoc().getBeginLoc(), TI,
12975 UPPC_FixedUnderlyingType))
12976 EnumUnderlying = Context.IntTy.getTypePtr();
12978 } else if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
12979 if (getLangOpts().MSVCCompat || TUK == TUK_Definition) {
12980 // Microsoft enums are always of int type.
12981 EnumUnderlying = Context.IntTy.getTypePtr();
12982 EnumUnderlyingIsImplicit = true;
12987 DeclContext *SearchDC = CurContext;
12988 DeclContext *DC = CurContext;
12989 bool isStdBadAlloc = false;
12990 bool isStdAlignValT = false;
12992 RedeclarationKind Redecl = ForRedeclaration;
12993 if (TUK == TUK_Friend || TUK == TUK_Reference)
12994 Redecl = NotForRedeclaration;
12996 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl);
12997 if (Name && SS.isNotEmpty()) {
12998 // We have a nested-name tag ('struct foo::bar').
13000 // Check for invalid 'foo::'.
13001 if (SS.isInvalid()) {
13003 goto CreateNewDecl;
13006 // If this is a friend or a reference to a class in a dependent
13007 // context, don't try to make a decl for it.
13008 if (TUK == TUK_Friend || TUK == TUK_Reference) {
13009 DC = computeDeclContext(SS, false);
13011 IsDependent = true;
13015 DC = computeDeclContext(SS, true);
13017 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec)
13023 if (RequireCompleteDeclContext(SS, DC))
13027 // Look-up name inside 'foo::'.
13028 LookupQualifiedName(Previous, DC);
13030 if (Previous.isAmbiguous())
13033 if (Previous.empty()) {
13034 // Name lookup did not find anything. However, if the
13035 // nested-name-specifier refers to the current instantiation,
13036 // and that current instantiation has any dependent base
13037 // classes, we might find something at instantiation time: treat
13038 // this as a dependent elaborated-type-specifier.
13039 // But this only makes any sense for reference-like lookups.
13040 if (Previous.wasNotFoundInCurrentInstantiation() &&
13041 (TUK == TUK_Reference || TUK == TUK_Friend)) {
13042 IsDependent = true;
13046 // A tag 'foo::bar' must already exist.
13047 Diag(NameLoc, diag::err_not_tag_in_scope)
13048 << Kind << Name << DC << SS.getRange();
13051 goto CreateNewDecl;
13054 // C++14 [class.mem]p14:
13055 // If T is the name of a class, then each of the following shall have a
13056 // name different from T:
13057 // -- every member of class T that is itself a type
13058 if (TUK != TUK_Reference && TUK != TUK_Friend &&
13059 DiagnoseClassNameShadow(SearchDC, DeclarationNameInfo(Name, NameLoc)))
13062 // If this is a named struct, check to see if there was a previous forward
13063 // declaration or definition.
13064 // FIXME: We're looking into outer scopes here, even when we
13065 // shouldn't be. Doing so can result in ambiguities that we
13066 // shouldn't be diagnosing.
13067 LookupName(Previous, S);
13069 // When declaring or defining a tag, ignore ambiguities introduced
13070 // by types using'ed into this scope.
13071 if (Previous.isAmbiguous() &&
13072 (TUK == TUK_Definition || TUK == TUK_Declaration)) {
13073 LookupResult::Filter F = Previous.makeFilter();
13074 while (F.hasNext()) {
13075 NamedDecl *ND = F.next();
13076 if (!ND->getDeclContext()->getRedeclContext()->Equals(
13077 SearchDC->getRedeclContext()))
13083 // C++11 [namespace.memdef]p3:
13084 // If the name in a friend declaration is neither qualified nor
13085 // a template-id and the declaration is a function or an
13086 // elaborated-type-specifier, the lookup to determine whether
13087 // the entity has been previously declared shall not consider
13088 // any scopes outside the innermost enclosing namespace.
13090 // MSVC doesn't implement the above rule for types, so a friend tag
13091 // declaration may be a redeclaration of a type declared in an enclosing
13092 // scope. They do implement this rule for friend functions.
13094 // Does it matter that this should be by scope instead of by
13095 // semantic context?
13096 if (!Previous.empty() && TUK == TUK_Friend) {
13097 DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext();
13098 LookupResult::Filter F = Previous.makeFilter();
13099 bool FriendSawTagOutsideEnclosingNamespace = false;
13100 while (F.hasNext()) {
13101 NamedDecl *ND = F.next();
13102 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
13103 if (DC->isFileContext() &&
13104 !EnclosingNS->Encloses(ND->getDeclContext())) {
13105 if (getLangOpts().MSVCCompat)
13106 FriendSawTagOutsideEnclosingNamespace = true;
13113 // Diagnose this MSVC extension in the easy case where lookup would have
13114 // unambiguously found something outside the enclosing namespace.
13115 if (Previous.isSingleResult() && FriendSawTagOutsideEnclosingNamespace) {
13116 NamedDecl *ND = Previous.getFoundDecl();
13117 Diag(NameLoc, diag::ext_friend_tag_redecl_outside_namespace)
13118 << createFriendTagNNSFixIt(*this, ND, S, NameLoc);
13122 // Note: there used to be some attempt at recovery here.
13123 if (Previous.isAmbiguous())
13126 if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) {
13127 // FIXME: This makes sure that we ignore the contexts associated
13128 // with C structs, unions, and enums when looking for a matching
13129 // tag declaration or definition. See the similar lookup tweak
13130 // in Sema::LookupName; is there a better way to deal with this?
13131 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
13132 SearchDC = SearchDC->getParent();
13136 if (Previous.isSingleResult() &&
13137 Previous.getFoundDecl()->isTemplateParameter()) {
13138 // Maybe we will complain about the shadowed template parameter.
13139 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
13140 // Just pretend that we didn't see the previous declaration.
13144 if (getLangOpts().CPlusPlus && Name && DC && StdNamespace &&
13145 DC->Equals(getStdNamespace())) {
13146 if (Name->isStr("bad_alloc")) {
13147 // This is a declaration of or a reference to "std::bad_alloc".
13148 isStdBadAlloc = true;
13150 // If std::bad_alloc has been implicitly declared (but made invisible to
13151 // name lookup), fill in this implicit declaration as the previous
13152 // declaration, so that the declarations get chained appropriately.
13153 if (Previous.empty() && StdBadAlloc)
13154 Previous.addDecl(getStdBadAlloc());
13155 } else if (Name->isStr("align_val_t")) {
13156 isStdAlignValT = true;
13157 if (Previous.empty() && StdAlignValT)
13158 Previous.addDecl(getStdAlignValT());
13162 // If we didn't find a previous declaration, and this is a reference
13163 // (or friend reference), move to the correct scope. In C++, we
13164 // also need to do a redeclaration lookup there, just in case
13165 // there's a shadow friend decl.
13166 if (Name && Previous.empty() &&
13167 (TUK == TUK_Reference || TUK == TUK_Friend)) {
13168 if (Invalid) goto CreateNewDecl;
13169 assert(SS.isEmpty());
13171 if (TUK == TUK_Reference) {
13172 // C++ [basic.scope.pdecl]p5:
13173 // -- for an elaborated-type-specifier of the form
13175 // class-key identifier
13177 // if the elaborated-type-specifier is used in the
13178 // decl-specifier-seq or parameter-declaration-clause of a
13179 // function defined in namespace scope, the identifier is
13180 // declared as a class-name in the namespace that contains
13181 // the declaration; otherwise, except as a friend
13182 // declaration, the identifier is declared in the smallest
13183 // non-class, non-function-prototype scope that contains the
13186 // C99 6.7.2.3p8 has a similar (but not identical!) provision for
13187 // C structs and unions.
13189 // It is an error in C++ to declare (rather than define) an enum
13190 // type, including via an elaborated type specifier. We'll
13191 // diagnose that later; for now, declare the enum in the same
13192 // scope as we would have picked for any other tag type.
13194 // GNU C also supports this behavior as part of its incomplete
13195 // enum types extension, while GNU C++ does not.
13197 // Find the context where we'll be declaring the tag.
13198 // FIXME: We would like to maintain the current DeclContext as the
13199 // lexical context,
13200 SearchDC = getTagInjectionContext(SearchDC);
13202 // Find the scope where we'll be declaring the tag.
13203 S = getTagInjectionScope(S, getLangOpts());
13205 assert(TUK == TUK_Friend);
13206 // C++ [namespace.memdef]p3:
13207 // If a friend declaration in a non-local class first declares a
13208 // class or function, the friend class or function is a member of
13209 // the innermost enclosing namespace.
13210 SearchDC = SearchDC->getEnclosingNamespaceContext();
13213 // In C++, we need to do a redeclaration lookup to properly
13214 // diagnose some problems.
13215 // FIXME: redeclaration lookup is also used (with and without C++) to find a
13216 // hidden declaration so that we don't get ambiguity errors when using a
13217 // type declared by an elaborated-type-specifier. In C that is not correct
13218 // and we should instead merge compatible types found by lookup.
13219 if (getLangOpts().CPlusPlus) {
13220 Previous.setRedeclarationKind(ForRedeclaration);
13221 LookupQualifiedName(Previous, SearchDC);
13223 Previous.setRedeclarationKind(ForRedeclaration);
13224 LookupName(Previous, S);
13228 // If we have a known previous declaration to use, then use it.
13229 if (Previous.empty() && SkipBody && SkipBody->Previous)
13230 Previous.addDecl(SkipBody->Previous);
13232 if (!Previous.empty()) {
13233 NamedDecl *PrevDecl = Previous.getFoundDecl();
13234 NamedDecl *DirectPrevDecl = Previous.getRepresentativeDecl();
13236 // It's okay to have a tag decl in the same scope as a typedef
13237 // which hides a tag decl in the same scope. Finding this
13238 // insanity with a redeclaration lookup can only actually happen
13241 // This is also okay for elaborated-type-specifiers, which is
13242 // technically forbidden by the current standard but which is
13243 // okay according to the likely resolution of an open issue;
13244 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
13245 if (getLangOpts().CPlusPlus) {
13246 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
13247 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
13248 TagDecl *Tag = TT->getDecl();
13249 if (Tag->getDeclName() == Name &&
13250 Tag->getDeclContext()->getRedeclContext()
13251 ->Equals(TD->getDeclContext()->getRedeclContext())) {
13254 Previous.addDecl(Tag);
13255 Previous.resolveKind();
13261 // If this is a redeclaration of a using shadow declaration, it must
13262 // declare a tag in the same context. In MSVC mode, we allow a
13263 // redefinition if either context is within the other.
13264 if (auto *Shadow = dyn_cast<UsingShadowDecl>(DirectPrevDecl)) {
13265 auto *OldTag = dyn_cast<TagDecl>(PrevDecl);
13266 if (SS.isEmpty() && TUK != TUK_Reference && TUK != TUK_Friend &&
13267 isDeclInScope(Shadow, SearchDC, S, isMemberSpecialization) &&
13268 !(OldTag && isAcceptableTagRedeclContext(
13269 *this, OldTag->getDeclContext(), SearchDC))) {
13270 Diag(KWLoc, diag::err_using_decl_conflict_reverse);
13271 Diag(Shadow->getTargetDecl()->getLocation(),
13272 diag::note_using_decl_target);
13273 Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl)
13275 // Recover by ignoring the old declaration.
13277 goto CreateNewDecl;
13281 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
13282 // If this is a use of a previous tag, or if the tag is already declared
13283 // in the same scope (so that the definition/declaration completes or
13284 // rementions the tag), reuse the decl.
13285 if (TUK == TUK_Reference || TUK == TUK_Friend ||
13286 isDeclInScope(DirectPrevDecl, SearchDC, S,
13287 SS.isNotEmpty() || isMemberSpecialization)) {
13288 // Make sure that this wasn't declared as an enum and now used as a
13289 // struct or something similar.
13290 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind,
13291 TUK == TUK_Definition, KWLoc,
13293 bool SafeToContinue
13294 = (PrevTagDecl->getTagKind() != TTK_Enum &&
13296 if (SafeToContinue)
13297 Diag(KWLoc, diag::err_use_with_wrong_tag)
13299 << FixItHint::CreateReplacement(SourceRange(KWLoc),
13300 PrevTagDecl->getKindName());
13302 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
13303 Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
13305 if (SafeToContinue)
13306 Kind = PrevTagDecl->getTagKind();
13308 // Recover by making this an anonymous redefinition.
13315 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
13316 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);
13318 // If this is an elaborated-type-specifier for a scoped enumeration,
13319 // the 'class' keyword is not necessary and not permitted.
13320 if (TUK == TUK_Reference || TUK == TUK_Friend) {
13322 Diag(ScopedEnumKWLoc, diag::err_enum_class_reference)
13323 << PrevEnum->isScoped()
13324 << FixItHint::CreateRemoval(ScopedEnumKWLoc);
13325 return PrevTagDecl;
13328 QualType EnumUnderlyingTy;
13329 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
13330 EnumUnderlyingTy = TI->getType().getUnqualifiedType();
13331 else if (const Type *T = EnumUnderlying.dyn_cast<const Type*>())
13332 EnumUnderlyingTy = QualType(T, 0);
13334 // All conflicts with previous declarations are recovered by
13335 // returning the previous declaration, unless this is a definition,
13336 // in which case we want the caller to bail out.
13337 if (CheckEnumRedeclaration(NameLoc.isValid() ? NameLoc : KWLoc,
13338 ScopedEnum, EnumUnderlyingTy,
13339 EnumUnderlyingIsImplicit, PrevEnum))
13340 return TUK == TUK_Declaration ? PrevTagDecl : nullptr;
13343 // C++11 [class.mem]p1:
13344 // A member shall not be declared twice in the member-specification,
13345 // except that a nested class or member class template can be declared
13346 // and then later defined.
13347 if (TUK == TUK_Declaration && PrevDecl->isCXXClassMember() &&
13348 S->isDeclScope(PrevDecl)) {
13349 Diag(NameLoc, diag::ext_member_redeclared);
13350 Diag(PrevTagDecl->getLocation(), diag::note_previous_declaration);
13354 // If this is a use, just return the declaration we found, unless
13355 // we have attributes.
13356 if (TUK == TUK_Reference || TUK == TUK_Friend) {
13358 // FIXME: Diagnose these attributes. For now, we create a new
13359 // declaration to hold them.
13360 } else if (TUK == TUK_Reference &&
13361 (PrevTagDecl->getFriendObjectKind() ==
13362 Decl::FOK_Undeclared ||
13363 PP.getModuleContainingLocation(
13364 PrevDecl->getLocation()) !=
13365 PP.getModuleContainingLocation(KWLoc)) &&
13367 // This declaration is a reference to an existing entity, but
13368 // has different visibility from that entity: it either makes
13369 // a friend visible or it makes a type visible in a new module.
13370 // In either case, create a new declaration. We only do this if
13371 // the declaration would have meant the same thing if no prior
13372 // declaration were found, that is, if it was found in the same
13373 // scope where we would have injected a declaration.
13374 if (!getTagInjectionContext(CurContext)->getRedeclContext()
13375 ->Equals(PrevDecl->getDeclContext()->getRedeclContext()))
13376 return PrevTagDecl;
13377 // This is in the injected scope, create a new declaration in
13379 S = getTagInjectionScope(S, getLangOpts());
13381 return PrevTagDecl;
13385 // Diagnose attempts to redefine a tag.
13386 if (TUK == TUK_Definition) {
13387 if (NamedDecl *Def = PrevTagDecl->getDefinition()) {
13388 // If we're defining a specialization and the previous definition
13389 // is from an implicit instantiation, don't emit an error
13390 // here; we'll catch this in the general case below.
13391 bool IsExplicitSpecializationAfterInstantiation = false;
13392 if (isMemberSpecialization) {
13393 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Def))
13394 IsExplicitSpecializationAfterInstantiation =
13395 RD->getTemplateSpecializationKind() !=
13396 TSK_ExplicitSpecialization;
13397 else if (EnumDecl *ED = dyn_cast<EnumDecl>(Def))
13398 IsExplicitSpecializationAfterInstantiation =
13399 ED->getTemplateSpecializationKind() !=
13400 TSK_ExplicitSpecialization;
13403 NamedDecl *Hidden = nullptr;
13404 if (SkipBody && getLangOpts().CPlusPlus &&
13405 !hasVisibleDefinition(Def, &Hidden)) {
13406 // There is a definition of this tag, but it is not visible. We
13407 // explicitly make use of C++'s one definition rule here, and
13408 // assume that this definition is identical to the hidden one
13409 // we already have. Make the existing definition visible and
13410 // use it in place of this one.
13411 SkipBody->ShouldSkip = true;
13412 makeMergedDefinitionVisible(Hidden, KWLoc);
13414 } else if (!IsExplicitSpecializationAfterInstantiation) {
13415 // A redeclaration in function prototype scope in C isn't
13416 // visible elsewhere, so merely issue a warning.
13417 if (!getLangOpts().CPlusPlus && S->containedInPrototypeScope())
13418 Diag(NameLoc, diag::warn_redefinition_in_param_list) << Name;
13420 Diag(NameLoc, diag::err_redefinition) << Name;
13421 Diag(Def->getLocation(), diag::note_previous_definition);
13422 // If this is a redefinition, recover by making this
13423 // struct be anonymous, which will make any later
13424 // references get the previous definition.
13430 // If the type is currently being defined, complain
13431 // about a nested redefinition.
13432 auto *TD = Context.getTagDeclType(PrevTagDecl)->getAsTagDecl();
13433 if (TD->isBeingDefined()) {
13434 Diag(NameLoc, diag::err_nested_redefinition) << Name;
13435 Diag(PrevTagDecl->getLocation(),
13436 diag::note_previous_definition);
13443 // Okay, this is definition of a previously declared or referenced
13444 // tag. We're going to create a new Decl for it.
13447 // Okay, we're going to make a redeclaration. If this is some kind
13448 // of reference, make sure we build the redeclaration in the same DC
13449 // as the original, and ignore the current access specifier.
13450 if (TUK == TUK_Friend || TUK == TUK_Reference) {
13451 SearchDC = PrevTagDecl->getDeclContext();
13455 // If we get here we have (another) forward declaration or we
13456 // have a definition. Just create a new decl.
13459 // If we get here, this is a definition of a new tag type in a nested
13460 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a
13461 // new decl/type. We set PrevDecl to NULL so that the entities
13462 // have distinct types.
13465 // If we get here, we're going to create a new Decl. If PrevDecl
13466 // is non-NULL, it's a definition of the tag declared by
13467 // PrevDecl. If it's NULL, we have a new definition.
13469 // Otherwise, PrevDecl is not a tag, but was found with tag
13470 // lookup. This is only actually possible in C++, where a few
13471 // things like templates still live in the tag namespace.
13473 // Use a better diagnostic if an elaborated-type-specifier
13474 // found the wrong kind of type on the first
13475 // (non-redeclaration) lookup.
13476 if ((TUK == TUK_Reference || TUK == TUK_Friend) &&
13477 !Previous.isForRedeclaration()) {
13478 NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl, Kind);
13479 Diag(NameLoc, diag::err_tag_reference_non_tag) << PrevDecl << NTK
13481 Diag(PrevDecl->getLocation(), diag::note_declared_at);
13484 // Otherwise, only diagnose if the declaration is in scope.
13485 } else if (!isDeclInScope(DirectPrevDecl, SearchDC, S,
13486 SS.isNotEmpty() || isMemberSpecialization)) {
13489 // Diagnose implicit declarations introduced by elaborated types.
13490 } else if (TUK == TUK_Reference || TUK == TUK_Friend) {
13491 NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl, Kind);
13492 Diag(NameLoc, diag::err_tag_reference_conflict) << NTK;
13493 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
13496 // Otherwise it's a declaration. Call out a particularly common
13498 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
13500 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
13501 Diag(NameLoc, diag::err_tag_definition_of_typedef)
13502 << Name << Kind << TND->getUnderlyingType();
13503 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
13506 // Otherwise, diagnose.
13508 // The tag name clashes with something else in the target scope,
13509 // issue an error and recover by making this tag be anonymous.
13510 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
13511 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
13516 // The existing declaration isn't relevant to us; we're in a
13517 // new scope, so clear out the previous declaration.
13524 TagDecl *PrevDecl = nullptr;
13525 if (Previous.isSingleResult())
13526 PrevDecl = cast<TagDecl>(Previous.getFoundDecl());
13528 // If there is an identifier, use the location of the identifier as the
13529 // location of the decl, otherwise use the location of the struct/union
13531 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc;
13533 // Otherwise, create a new declaration. If there is a previous
13534 // declaration of the same entity, the two will be linked via
13538 bool IsForwardReference = false;
13539 if (Kind == TTK_Enum) {
13540 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
13541 // enum X { A, B, C } D; D should chain to X.
13542 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name,
13543 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum,
13544 ScopedEnumUsesClassTag, !EnumUnderlying.isNull());
13546 if (isStdAlignValT && (!StdAlignValT || getStdAlignValT()->isImplicit()))
13547 StdAlignValT = cast<EnumDecl>(New);
13549 // If this is an undefined enum, warn.
13550 if (TUK != TUK_Definition && !Invalid) {
13552 if (!EnumUnderlyingIsImplicit &&
13553 (getLangOpts().CPlusPlus11 || getLangOpts().ObjC2) &&
13554 cast<EnumDecl>(New)->isFixed()) {
13555 // C++0x: 7.2p2: opaque-enum-declaration.
13556 // Conflicts are diagnosed above. Do nothing.
13558 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) {
13559 Diag(Loc, diag::ext_forward_ref_enum_def)
13561 Diag(Def->getLocation(), diag::note_previous_definition);
13563 unsigned DiagID = diag::ext_forward_ref_enum;
13564 if (getLangOpts().MSVCCompat)
13565 DiagID = diag::ext_ms_forward_ref_enum;
13566 else if (getLangOpts().CPlusPlus)
13567 DiagID = diag::err_forward_ref_enum;
13570 // If this is a forward-declared reference to an enumeration, make a
13571 // note of it; we won't actually be introducing the declaration into
13572 // the declaration context.
13573 if (TUK == TUK_Reference)
13574 IsForwardReference = true;
13578 if (EnumUnderlying) {
13579 EnumDecl *ED = cast<EnumDecl>(New);
13580 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
13581 ED->setIntegerTypeSourceInfo(TI);
13583 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
13584 ED->setPromotionType(ED->getIntegerType());
13587 // struct/union/class
13589 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
13590 // struct X { int A; } D; D should chain to X.
13591 if (getLangOpts().CPlusPlus) {
13592 // FIXME: Look for a way to use RecordDecl for simple structs.
13593 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
13594 cast_or_null<CXXRecordDecl>(PrevDecl));
13596 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit()))
13597 StdBadAlloc = cast<CXXRecordDecl>(New);
13599 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
13600 cast_or_null<RecordDecl>(PrevDecl));
13603 // C++11 [dcl.type]p3:
13604 // A type-specifier-seq shall not define a class or enumeration [...].
13605 if (getLangOpts().CPlusPlus && IsTypeSpecifier && TUK == TUK_Definition) {
13606 Diag(New->getLocation(), diag::err_type_defined_in_type_specifier)
13607 << Context.getTagDeclType(New);
13611 // Maybe add qualifier info.
13612 if (SS.isNotEmpty()) {
13614 // If this is either a declaration or a definition, check the
13615 // nested-name-specifier against the current context. We don't do this
13616 // for explicit specializations, because they have similar checking
13617 // (with more specific diagnostics) in the call to
13618 // CheckMemberSpecialization, below.
13619 if (!isMemberSpecialization &&
13620 (TUK == TUK_Definition || TUK == TUK_Declaration) &&
13621 diagnoseQualifiedDeclaration(SS, DC, OrigName, Loc))
13624 New->setQualifierInfo(SS.getWithLocInContext(Context));
13625 if (TemplateParameterLists.size() > 0) {
13626 New->setTemplateParameterListsInfo(Context, TemplateParameterLists);
13633 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) {
13634 // Add alignment attributes if necessary; these attributes are checked when
13635 // the ASTContext lays out the structure.
13637 // It is important for implementing the correct semantics that this
13638 // happen here (in act on tag decl). The #pragma pack stack is
13639 // maintained as a result of parser callbacks which can occur at
13640 // many points during the parsing of a struct declaration (because
13641 // the #pragma tokens are effectively skipped over during the
13642 // parsing of the struct).
13643 if (TUK == TUK_Definition) {
13644 AddAlignmentAttributesForRecord(RD);
13645 AddMsStructLayoutForRecord(RD);
13649 if (ModulePrivateLoc.isValid()) {
13650 if (isMemberSpecialization)
13651 Diag(New->getLocation(), diag::err_module_private_specialization)
13653 << FixItHint::CreateRemoval(ModulePrivateLoc);
13654 // __module_private__ does not apply to local classes. However, we only
13655 // diagnose this as an error when the declaration specifiers are
13656 // freestanding. Here, we just ignore the __module_private__.
13657 else if (!SearchDC->isFunctionOrMethod())
13658 New->setModulePrivate();
13661 // If this is a specialization of a member class (of a class template),
13662 // check the specialization.
13663 if (isMemberSpecialization && CheckMemberSpecialization(New, Previous))
13666 // If we're declaring or defining a tag in function prototype scope in C,
13667 // note that this type can only be used within the function and add it to
13668 // the list of decls to inject into the function definition scope.
13669 if ((Name || Kind == TTK_Enum) &&
13670 getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
13671 if (getLangOpts().CPlusPlus) {
13672 // C++ [dcl.fct]p6:
13673 // Types shall not be defined in return or parameter types.
13674 if (TUK == TUK_Definition && !IsTypeSpecifier) {
13675 Diag(Loc, diag::err_type_defined_in_param_type)
13679 } else if (!PrevDecl) {
13680 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
13685 New->setInvalidDecl();
13687 // Set the lexical context. If the tag has a C++ scope specifier, the
13688 // lexical context will be different from the semantic context.
13689 New->setLexicalDeclContext(CurContext);
13691 // Mark this as a friend decl if applicable.
13692 // In Microsoft mode, a friend declaration also acts as a forward
13693 // declaration so we always pass true to setObjectOfFriendDecl to make
13694 // the tag name visible.
13695 if (TUK == TUK_Friend)
13696 New->setObjectOfFriendDecl(getLangOpts().MSVCCompat);
13698 // Set the access specifier.
13699 if (!Invalid && SearchDC->isRecord())
13700 SetMemberAccessSpecifier(New, PrevDecl, AS);
13702 if (TUK == TUK_Definition)
13703 New->startDefinition();
13706 ProcessDeclAttributeList(S, New, Attr);
13707 AddPragmaAttributes(S, New);
13709 // If this has an identifier, add it to the scope stack.
13710 if (TUK == TUK_Friend) {
13711 // We might be replacing an existing declaration in the lookup tables;
13712 // if so, borrow its access specifier.
13714 New->setAccess(PrevDecl->getAccess());
13716 DeclContext *DC = New->getDeclContext()->getRedeclContext();
13717 DC->makeDeclVisibleInContext(New);
13718 if (Name) // can be null along some error paths
13719 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
13720 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false);
13722 S = getNonFieldDeclScope(S);
13723 PushOnScopeChains(New, S, !IsForwardReference);
13724 if (IsForwardReference)
13725 SearchDC->makeDeclVisibleInContext(New);
13727 CurContext->addDecl(New);
13730 // If this is the C FILE type, notify the AST context.
13731 if (IdentifierInfo *II = New->getIdentifier())
13732 if (!New->isInvalidDecl() &&
13733 New->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
13735 Context.setFILEDecl(New);
13738 mergeDeclAttributes(New, PrevDecl);
13740 // If there's a #pragma GCC visibility in scope, set the visibility of this
13742 AddPushedVisibilityAttribute(New);
13745 // In C++, don't return an invalid declaration. We can't recover well from
13746 // the cases where we make the type anonymous.
13747 if (Invalid && getLangOpts().CPlusPlus) {
13748 if (New->isBeingDefined())
13749 if (auto RD = dyn_cast<RecordDecl>(New))
13750 RD->completeDefinition();
13757 void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) {
13758 AdjustDeclIfTemplate(TagD);
13759 TagDecl *Tag = cast<TagDecl>(TagD);
13761 // Enter the tag context.
13762 PushDeclContext(S, Tag);
13764 ActOnDocumentableDecl(TagD);
13766 // If there's a #pragma GCC visibility in scope, set the visibility of this
13768 AddPushedVisibilityAttribute(Tag);
13771 Decl *Sema::ActOnObjCContainerStartDefinition(Decl *IDecl) {
13772 assert(isa<ObjCContainerDecl>(IDecl) &&
13773 "ActOnObjCContainerStartDefinition - Not ObjCContainerDecl");
13774 DeclContext *OCD = cast<DeclContext>(IDecl);
13775 assert(getContainingDC(OCD) == CurContext &&
13776 "The next DeclContext should be lexically contained in the current one.");
13781 void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD,
13782 SourceLocation FinalLoc,
13783 bool IsFinalSpelledSealed,
13784 SourceLocation LBraceLoc) {
13785 AdjustDeclIfTemplate(TagD);
13786 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD);
13788 FieldCollector->StartClass();
13790 if (!Record->getIdentifier())
13793 if (FinalLoc.isValid())
13794 Record->addAttr(new (Context)
13795 FinalAttr(FinalLoc, Context, IsFinalSpelledSealed));
13798 // [...] The class-name is also inserted into the scope of the
13799 // class itself; this is known as the injected-class-name. For
13800 // purposes of access checking, the injected-class-name is treated
13801 // as if it were a public member name.
13802 CXXRecordDecl *InjectedClassName
13803 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext,
13804 Record->getLocStart(), Record->getLocation(),
13805 Record->getIdentifier(),
13806 /*PrevDecl=*/nullptr,
13807 /*DelayTypeCreation=*/true);
13808 Context.getTypeDeclType(InjectedClassName, Record);
13809 InjectedClassName->setImplicit();
13810 InjectedClassName->setAccess(AS_public);
13811 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate())
13812 InjectedClassName->setDescribedClassTemplate(Template);
13813 PushOnScopeChains(InjectedClassName, S);
13814 assert(InjectedClassName->isInjectedClassName() &&
13815 "Broken injected-class-name");
13818 void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD,
13819 SourceRange BraceRange) {
13820 AdjustDeclIfTemplate(TagD);
13821 TagDecl *Tag = cast<TagDecl>(TagD);
13822 Tag->setBraceRange(BraceRange);
13824 // Make sure we "complete" the definition even it is invalid.
13825 if (Tag->isBeingDefined()) {
13826 assert(Tag->isInvalidDecl() && "We should already have completed it");
13827 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
13828 RD->completeDefinition();
13831 if (isa<CXXRecordDecl>(Tag)) {
13832 FieldCollector->FinishClass();
13835 // Exit this scope of this tag's definition.
13838 if (getCurLexicalContext()->isObjCContainer() &&
13839 Tag->getDeclContext()->isFileContext())
13840 Tag->setTopLevelDeclInObjCContainer();
13842 // Notify the consumer that we've defined a tag.
13843 if (!Tag->isInvalidDecl())
13844 Consumer.HandleTagDeclDefinition(Tag);
13847 void Sema::ActOnObjCContainerFinishDefinition() {
13848 // Exit this scope of this interface definition.
13852 void Sema::ActOnObjCTemporaryExitContainerContext(DeclContext *DC) {
13853 assert(DC == CurContext && "Mismatch of container contexts");
13854 OriginalLexicalContext = DC;
13855 ActOnObjCContainerFinishDefinition();
13858 void Sema::ActOnObjCReenterContainerContext(DeclContext *DC) {
13859 ActOnObjCContainerStartDefinition(cast<Decl>(DC));
13860 OriginalLexicalContext = nullptr;
13863 void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) {
13864 AdjustDeclIfTemplate(TagD);
13865 TagDecl *Tag = cast<TagDecl>(TagD);
13866 Tag->setInvalidDecl();
13868 // Make sure we "complete" the definition even it is invalid.
13869 if (Tag->isBeingDefined()) {
13870 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
13871 RD->completeDefinition();
13874 // We're undoing ActOnTagStartDefinition here, not
13875 // ActOnStartCXXMemberDeclarations, so we don't have to mess with
13876 // the FieldCollector.
13881 // Note that FieldName may be null for anonymous bitfields.
13882 ExprResult Sema::VerifyBitField(SourceLocation FieldLoc,
13883 IdentifierInfo *FieldName,
13884 QualType FieldTy, bool IsMsStruct,
13885 Expr *BitWidth, bool *ZeroWidth) {
13886 // Default to true; that shouldn't confuse checks for emptiness
13890 // C99 6.7.2.1p4 - verify the field type.
13891 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
13892 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) {
13893 // Handle incomplete types with specific error.
13894 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete))
13895 return ExprError();
13897 return Diag(FieldLoc, diag::err_not_integral_type_bitfield)
13898 << FieldName << FieldTy << BitWidth->getSourceRange();
13899 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield)
13900 << FieldTy << BitWidth->getSourceRange();
13901 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth),
13902 UPPC_BitFieldWidth))
13903 return ExprError();
13905 // If the bit-width is type- or value-dependent, don't try to check
13907 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent())
13910 llvm::APSInt Value;
13911 ExprResult ICE = VerifyIntegerConstantExpression(BitWidth, &Value);
13912 if (ICE.isInvalid())
13914 BitWidth = ICE.get();
13916 if (Value != 0 && ZeroWidth)
13917 *ZeroWidth = false;
13919 // Zero-width bitfield is ok for anonymous field.
13920 if (Value == 0 && FieldName)
13921 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName;
13923 if (Value.isSigned() && Value.isNegative()) {
13925 return Diag(FieldLoc, diag::err_bitfield_has_negative_width)
13926 << FieldName << Value.toString(10);
13927 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width)
13928 << Value.toString(10);
13931 if (!FieldTy->isDependentType()) {
13932 uint64_t TypeStorageSize = Context.getTypeSize(FieldTy);
13933 uint64_t TypeWidth = Context.getIntWidth(FieldTy);
13934 bool BitfieldIsOverwide = Value.ugt(TypeWidth);
13936 // Over-wide bitfields are an error in C or when using the MSVC bitfield
13938 bool CStdConstraintViolation =
13939 BitfieldIsOverwide && !getLangOpts().CPlusPlus;
13940 bool MSBitfieldViolation =
13941 Value.ugt(TypeStorageSize) &&
13942 (IsMsStruct || Context.getTargetInfo().getCXXABI().isMicrosoft());
13943 if (CStdConstraintViolation || MSBitfieldViolation) {
13944 unsigned DiagWidth =
13945 CStdConstraintViolation ? TypeWidth : TypeStorageSize;
13947 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_width)
13948 << FieldName << (unsigned)Value.getZExtValue()
13949 << !CStdConstraintViolation << DiagWidth;
13951 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_width)
13952 << (unsigned)Value.getZExtValue() << !CStdConstraintViolation
13956 // Warn on types where the user might conceivably expect to get all
13957 // specified bits as value bits: that's all integral types other than
13959 if (BitfieldIsOverwide && !FieldTy->isBooleanType()) {
13961 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_width)
13962 << FieldName << (unsigned)Value.getZExtValue()
13963 << (unsigned)TypeWidth;
13965 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_width)
13966 << (unsigned)Value.getZExtValue() << (unsigned)TypeWidth;
13973 /// ActOnField - Each field of a C struct/union is passed into this in order
13974 /// to create a FieldDecl object for it.
13975 Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
13976 Declarator &D, Expr *BitfieldWidth) {
13977 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD),
13978 DeclStart, D, static_cast<Expr*>(BitfieldWidth),
13979 /*InitStyle=*/ICIS_NoInit, AS_public);
13983 /// HandleField - Analyze a field of a C struct or a C++ data member.
13985 FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
13986 SourceLocation DeclStart,
13987 Declarator &D, Expr *BitWidth,
13988 InClassInitStyle InitStyle,
13989 AccessSpecifier AS) {
13990 if (D.isDecompositionDeclarator()) {
13991 const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
13992 Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
13993 << Decomp.getSourceRange();
13997 IdentifierInfo *II = D.getIdentifier();
13998 SourceLocation Loc = DeclStart;
13999 if (II) Loc = D.getIdentifierLoc();
14001 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
14002 QualType T = TInfo->getType();
14003 if (getLangOpts().CPlusPlus) {
14004 CheckExtraCXXDefaultArguments(D);
14006 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
14007 UPPC_DataMemberType)) {
14008 D.setInvalidType();
14010 TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
14014 // TR 18037 does not allow fields to be declared with address spaces.
14015 if (T.getQualifiers().hasAddressSpace()) {
14016 Diag(Loc, diag::err_field_with_address_space);
14017 D.setInvalidType();
14020 // OpenCL v1.2 s6.9b,r & OpenCL v2.0 s6.12.5 - The following types cannot be
14021 // used as structure or union field: image, sampler, event or block types.
14022 if (LangOpts.OpenCL && (T->isEventT() || T->isImageType() ||
14023 T->isSamplerT() || T->isBlockPointerType())) {
14024 Diag(Loc, diag::err_opencl_type_struct_or_union_field) << T;
14025 D.setInvalidType();
14028 DiagnoseFunctionSpecifiers(D.getDeclSpec());
14030 if (D.getDeclSpec().isInlineSpecified())
14031 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
14032 << getLangOpts().CPlusPlus1z;
14033 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
14034 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
14035 diag::err_invalid_thread)
14036 << DeclSpec::getSpecifierName(TSCS);
14038 // Check to see if this name was declared as a member previously
14039 NamedDecl *PrevDecl = nullptr;
14040 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
14041 LookupName(Previous, S);
14042 switch (Previous.getResultKind()) {
14043 case LookupResult::Found:
14044 case LookupResult::FoundUnresolvedValue:
14045 PrevDecl = Previous.getAsSingle<NamedDecl>();
14048 case LookupResult::FoundOverloaded:
14049 PrevDecl = Previous.getRepresentativeDecl();
14052 case LookupResult::NotFound:
14053 case LookupResult::NotFoundInCurrentInstantiation:
14054 case LookupResult::Ambiguous:
14057 Previous.suppressDiagnostics();
14059 if (PrevDecl && PrevDecl->isTemplateParameter()) {
14060 // Maybe we will complain about the shadowed template parameter.
14061 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
14062 // Just pretend that we didn't see the previous declaration.
14063 PrevDecl = nullptr;
14066 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
14067 PrevDecl = nullptr;
14070 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable);
14071 SourceLocation TSSL = D.getLocStart();
14073 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, InitStyle,
14074 TSSL, AS, PrevDecl, &D);
14076 if (NewFD->isInvalidDecl())
14077 Record->setInvalidDecl();
14079 if (D.getDeclSpec().isModulePrivateSpecified())
14080 NewFD->setModulePrivate();
14082 if (NewFD->isInvalidDecl() && PrevDecl) {
14083 // Don't introduce NewFD into scope; there's already something
14084 // with the same name in the same scope.
14086 PushOnScopeChains(NewFD, S);
14088 Record->addDecl(NewFD);
14093 /// \brief Build a new FieldDecl and check its well-formedness.
14095 /// This routine builds a new FieldDecl given the fields name, type,
14096 /// record, etc. \p PrevDecl should refer to any previous declaration
14097 /// with the same name and in the same scope as the field to be
14100 /// \returns a new FieldDecl.
14102 /// \todo The Declarator argument is a hack. It will be removed once
14103 FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T,
14104 TypeSourceInfo *TInfo,
14105 RecordDecl *Record, SourceLocation Loc,
14106 bool Mutable, Expr *BitWidth,
14107 InClassInitStyle InitStyle,
14108 SourceLocation TSSL,
14109 AccessSpecifier AS, NamedDecl *PrevDecl,
14111 IdentifierInfo *II = Name.getAsIdentifierInfo();
14112 bool InvalidDecl = false;
14113 if (D) InvalidDecl = D->isInvalidType();
14115 // If we receive a broken type, recover by assuming 'int' and
14116 // marking this declaration as invalid.
14118 InvalidDecl = true;
14122 QualType EltTy = Context.getBaseElementType(T);
14123 if (!EltTy->isDependentType()) {
14124 if (RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) {
14125 // Fields of incomplete type force their record to be invalid.
14126 Record->setInvalidDecl();
14127 InvalidDecl = true;
14130 EltTy->isIncompleteType(&Def);
14131 if (Def && Def->isInvalidDecl()) {
14132 Record->setInvalidDecl();
14133 InvalidDecl = true;
14138 // OpenCL v1.2 s6.9.c: bitfields are not supported.
14139 if (BitWidth && getLangOpts().OpenCL) {
14140 Diag(Loc, diag::err_opencl_bitfields);
14141 InvalidDecl = true;
14144 // C99 6.7.2.1p8: A member of a structure or union may have any type other
14145 // than a variably modified type.
14146 if (!InvalidDecl && T->isVariablyModifiedType()) {
14147 bool SizeIsNegative;
14148 llvm::APSInt Oversized;
14150 TypeSourceInfo *FixedTInfo =
14151 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
14155 Diag(Loc, diag::warn_illegal_constant_array_size);
14156 TInfo = FixedTInfo;
14157 T = FixedTInfo->getType();
14159 if (SizeIsNegative)
14160 Diag(Loc, diag::err_typecheck_negative_array_size);
14161 else if (Oversized.getBoolValue())
14162 Diag(Loc, diag::err_array_too_large)
14163 << Oversized.toString(10);
14165 Diag(Loc, diag::err_typecheck_field_variable_size);
14166 InvalidDecl = true;
14170 // Fields can not have abstract class types
14171 if (!InvalidDecl && RequireNonAbstractType(Loc, T,
14172 diag::err_abstract_type_in_decl,
14173 AbstractFieldType))
14174 InvalidDecl = true;
14176 bool ZeroWidth = false;
14178 BitWidth = nullptr;
14179 // If this is declared as a bit-field, check the bit-field.
14181 BitWidth = VerifyBitField(Loc, II, T, Record->isMsStruct(Context), BitWidth,
14184 InvalidDecl = true;
14185 BitWidth = nullptr;
14190 // Check that 'mutable' is consistent with the type of the declaration.
14191 if (!InvalidDecl && Mutable) {
14192 unsigned DiagID = 0;
14193 if (T->isReferenceType())
14194 DiagID = getLangOpts().MSVCCompat ? diag::ext_mutable_reference
14195 : diag::err_mutable_reference;
14196 else if (T.isConstQualified())
14197 DiagID = diag::err_mutable_const;
14200 SourceLocation ErrLoc = Loc;
14201 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid())
14202 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc();
14203 Diag(ErrLoc, DiagID);
14204 if (DiagID != diag::ext_mutable_reference) {
14206 InvalidDecl = true;
14211 // C++11 [class.union]p8 (DR1460):
14212 // At most one variant member of a union may have a
14213 // brace-or-equal-initializer.
14214 if (InitStyle != ICIS_NoInit)
14215 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Record), Loc);
14217 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo,
14218 BitWidth, Mutable, InitStyle);
14220 NewFD->setInvalidDecl();
14222 if (PrevDecl && !isa<TagDecl>(PrevDecl)) {
14223 Diag(Loc, diag::err_duplicate_member) << II;
14224 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
14225 NewFD->setInvalidDecl();
14228 if (!InvalidDecl && getLangOpts().CPlusPlus) {
14229 if (Record->isUnion()) {
14230 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
14231 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl());
14232 if (RDecl->getDefinition()) {
14233 // C++ [class.union]p1: An object of a class with a non-trivial
14234 // constructor, a non-trivial copy constructor, a non-trivial
14235 // destructor, or a non-trivial copy assignment operator
14236 // cannot be a member of a union, nor can an array of such
14238 if (CheckNontrivialField(NewFD))
14239 NewFD->setInvalidDecl();
14243 // C++ [class.union]p1: If a union contains a member of reference type,
14244 // the program is ill-formed, except when compiling with MSVC extensions
14246 if (EltTy->isReferenceType()) {
14247 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
14248 diag::ext_union_member_of_reference_type :
14249 diag::err_union_member_of_reference_type)
14250 << NewFD->getDeclName() << EltTy;
14251 if (!getLangOpts().MicrosoftExt)
14252 NewFD->setInvalidDecl();
14257 // FIXME: We need to pass in the attributes given an AST
14258 // representation, not a parser representation.
14260 // FIXME: The current scope is almost... but not entirely... correct here.
14261 ProcessDeclAttributes(getCurScope(), NewFD, *D);
14263 if (NewFD->hasAttrs())
14264 CheckAlignasUnderalignment(NewFD);
14267 // In auto-retain/release, infer strong retension for fields of
14268 // retainable type.
14269 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewFD))
14270 NewFD->setInvalidDecl();
14272 if (T.isObjCGCWeak())
14273 Diag(Loc, diag::warn_attribute_weak_on_field);
14275 NewFD->setAccess(AS);
14279 bool Sema::CheckNontrivialField(FieldDecl *FD) {
14281 assert(getLangOpts().CPlusPlus && "valid check only for C++");
14283 if (FD->isInvalidDecl() || FD->getType()->isDependentType())
14286 QualType EltTy = Context.getBaseElementType(FD->getType());
14287 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
14288 CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl());
14289 if (RDecl->getDefinition()) {
14290 // We check for copy constructors before constructors
14291 // because otherwise we'll never get complaints about
14292 // copy constructors.
14294 CXXSpecialMember member = CXXInvalid;
14295 // We're required to check for any non-trivial constructors. Since the
14296 // implicit default constructor is suppressed if there are any
14297 // user-declared constructors, we just need to check that there is a
14298 // trivial default constructor and a trivial copy constructor. (We don't
14299 // worry about move constructors here, since this is a C++98 check.)
14300 if (RDecl->hasNonTrivialCopyConstructor())
14301 member = CXXCopyConstructor;
14302 else if (!RDecl->hasTrivialDefaultConstructor())
14303 member = CXXDefaultConstructor;
14304 else if (RDecl->hasNonTrivialCopyAssignment())
14305 member = CXXCopyAssignment;
14306 else if (RDecl->hasNonTrivialDestructor())
14307 member = CXXDestructor;
14309 if (member != CXXInvalid) {
14310 if (!getLangOpts().CPlusPlus11 &&
14311 getLangOpts().ObjCAutoRefCount && RDecl->hasObjectMember()) {
14312 // Objective-C++ ARC: it is an error to have a non-trivial field of
14313 // a union. However, system headers in Objective-C programs
14314 // occasionally have Objective-C lifetime objects within unions,
14315 // and rather than cause the program to fail, we make those
14316 // members unavailable.
14317 SourceLocation Loc = FD->getLocation();
14318 if (getSourceManager().isInSystemHeader(Loc)) {
14319 if (!FD->hasAttr<UnavailableAttr>())
14320 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
14321 UnavailableAttr::IR_ARCFieldWithOwnership, Loc));
14326 Diag(FD->getLocation(), getLangOpts().CPlusPlus11 ?
14327 diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member :
14328 diag::err_illegal_union_or_anon_struct_member)
14329 << FD->getParent()->isUnion() << FD->getDeclName() << member;
14330 DiagnoseNontrivial(RDecl, member);
14331 return !getLangOpts().CPlusPlus11;
14339 /// TranslateIvarVisibility - Translate visibility from a token ID to an
14340 /// AST enum value.
14341 static ObjCIvarDecl::AccessControl
14342 TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) {
14343 switch (ivarVisibility) {
14344 default: llvm_unreachable("Unknown visitibility kind");
14345 case tok::objc_private: return ObjCIvarDecl::Private;
14346 case tok::objc_public: return ObjCIvarDecl::Public;
14347 case tok::objc_protected: return ObjCIvarDecl::Protected;
14348 case tok::objc_package: return ObjCIvarDecl::Package;
14352 /// ActOnIvar - Each ivar field of an objective-c class is passed into this
14353 /// in order to create an IvarDecl object for it.
14354 Decl *Sema::ActOnIvar(Scope *S,
14355 SourceLocation DeclStart,
14356 Declarator &D, Expr *BitfieldWidth,
14357 tok::ObjCKeywordKind Visibility) {
14359 IdentifierInfo *II = D.getIdentifier();
14360 Expr *BitWidth = (Expr*)BitfieldWidth;
14361 SourceLocation Loc = DeclStart;
14362 if (II) Loc = D.getIdentifierLoc();
14364 // FIXME: Unnamed fields can be handled in various different ways, for
14365 // example, unnamed unions inject all members into the struct namespace!
14367 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
14368 QualType T = TInfo->getType();
14371 // 6.7.2.1p3, 6.7.2.1p4
14372 BitWidth = VerifyBitField(Loc, II, T, /*IsMsStruct*/false, BitWidth).get();
14374 D.setInvalidType();
14381 if (T->isReferenceType()) {
14382 Diag(Loc, diag::err_ivar_reference_type);
14383 D.setInvalidType();
14385 // C99 6.7.2.1p8: A member of a structure or union may have any type other
14386 // than a variably modified type.
14387 else if (T->isVariablyModifiedType()) {
14388 Diag(Loc, diag::err_typecheck_ivar_variable_size);
14389 D.setInvalidType();
14392 // Get the visibility (access control) for this ivar.
14393 ObjCIvarDecl::AccessControl ac =
14394 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility)
14395 : ObjCIvarDecl::None;
14396 // Must set ivar's DeclContext to its enclosing interface.
14397 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(CurContext);
14398 if (!EnclosingDecl || EnclosingDecl->isInvalidDecl())
14400 ObjCContainerDecl *EnclosingContext;
14401 if (ObjCImplementationDecl *IMPDecl =
14402 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
14403 if (LangOpts.ObjCRuntime.isFragile()) {
14404 // Case of ivar declared in an implementation. Context is that of its class.
14405 EnclosingContext = IMPDecl->getClassInterface();
14406 assert(EnclosingContext && "Implementation has no class interface!");
14409 EnclosingContext = EnclosingDecl;
14411 if (ObjCCategoryDecl *CDecl =
14412 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
14413 if (LangOpts.ObjCRuntime.isFragile() || !CDecl->IsClassExtension()) {
14414 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension();
14418 EnclosingContext = EnclosingDecl;
14421 // Construct the decl.
14422 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext,
14423 DeclStart, Loc, II, T,
14424 TInfo, ac, (Expr *)BitfieldWidth);
14427 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName,
14429 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S)
14430 && !isa<TagDecl>(PrevDecl)) {
14431 Diag(Loc, diag::err_duplicate_member) << II;
14432 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
14433 NewID->setInvalidDecl();
14437 // Process attributes attached to the ivar.
14438 ProcessDeclAttributes(S, NewID, D);
14440 if (D.isInvalidType())
14441 NewID->setInvalidDecl();
14443 // In ARC, infer 'retaining' for ivars of retainable type.
14444 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewID))
14445 NewID->setInvalidDecl();
14447 if (D.getDeclSpec().isModulePrivateSpecified())
14448 NewID->setModulePrivate();
14451 // FIXME: When interfaces are DeclContexts, we'll need to add
14452 // these to the interface.
14454 IdResolver.AddDecl(NewID);
14457 if (LangOpts.ObjCRuntime.isNonFragile() &&
14458 !NewID->isInvalidDecl() && isa<ObjCInterfaceDecl>(EnclosingDecl))
14459 Diag(Loc, diag::warn_ivars_in_interface);
14464 /// ActOnLastBitfield - This routine handles synthesized bitfields rules for
14465 /// class and class extensions. For every class \@interface and class
14466 /// extension \@interface, if the last ivar is a bitfield of any type,
14467 /// then add an implicit `char :0` ivar to the end of that interface.
14468 void Sema::ActOnLastBitfield(SourceLocation DeclLoc,
14469 SmallVectorImpl<Decl *> &AllIvarDecls) {
14470 if (LangOpts.ObjCRuntime.isFragile() || AllIvarDecls.empty())
14473 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1];
14474 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl);
14476 if (!Ivar->isBitField() || Ivar->getBitWidthValue(Context) == 0)
14478 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CurContext);
14480 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(CurContext)) {
14481 if (!CD->IsClassExtension())
14484 // No need to add this to end of @implementation.
14488 // All conditions are met. Add a new bitfield to the tail end of ivars.
14489 llvm::APInt Zero(Context.getTypeSize(Context.IntTy), 0);
14490 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.IntTy, DeclLoc);
14492 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(CurContext),
14493 DeclLoc, DeclLoc, nullptr,
14495 Context.getTrivialTypeSourceInfo(Context.CharTy,
14497 ObjCIvarDecl::Private, BW,
14499 AllIvarDecls.push_back(Ivar);
14502 void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
14503 ArrayRef<Decl *> Fields, SourceLocation LBrac,
14504 SourceLocation RBrac, AttributeList *Attr) {
14505 assert(EnclosingDecl && "missing record or interface decl");
14507 // If this is an Objective-C @implementation or category and we have
14508 // new fields here we should reset the layout of the interface since
14509 // it will now change.
14510 if (!Fields.empty() && isa<ObjCContainerDecl>(EnclosingDecl)) {
14511 ObjCContainerDecl *DC = cast<ObjCContainerDecl>(EnclosingDecl);
14512 switch (DC->getKind()) {
14514 case Decl::ObjCCategory:
14515 Context.ResetObjCLayout(cast<ObjCCategoryDecl>(DC)->getClassInterface());
14517 case Decl::ObjCImplementation:
14519 ResetObjCLayout(cast<ObjCImplementationDecl>(DC)->getClassInterface());
14524 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl);
14526 // Start counting up the number of named members; make sure to include
14527 // members of anonymous structs and unions in the total.
14528 unsigned NumNamedMembers = 0;
14530 for (const auto *I : Record->decls()) {
14531 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
14532 if (IFD->getDeclName())
14537 // Verify that all the fields are okay.
14538 SmallVector<FieldDecl*, 32> RecFields;
14540 bool ObjCFieldLifetimeErrReported = false;
14541 for (ArrayRef<Decl *>::iterator i = Fields.begin(), end = Fields.end();
14543 FieldDecl *FD = cast<FieldDecl>(*i);
14545 // Get the type for the field.
14546 const Type *FDTy = FD->getType().getTypePtr();
14548 if (!FD->isAnonymousStructOrUnion()) {
14549 // Remember all fields written by the user.
14550 RecFields.push_back(FD);
14553 // If the field is already invalid for some reason, don't emit more
14554 // diagnostics about it.
14555 if (FD->isInvalidDecl()) {
14556 EnclosingDecl->setInvalidDecl();
14561 // A structure or union shall not contain a member with
14562 // incomplete or function type (hence, a structure shall not
14563 // contain an instance of itself, but may contain a pointer to
14564 // an instance of itself), except that the last member of a
14565 // structure with more than one named member may have incomplete
14566 // array type; such a structure (and any union containing,
14567 // possibly recursively, a member that is such a structure)
14568 // shall not be a member of a structure or an element of an
14570 if (FDTy->isFunctionType()) {
14571 // Field declared as a function.
14572 Diag(FD->getLocation(), diag::err_field_declared_as_function)
14573 << FD->getDeclName();
14574 FD->setInvalidDecl();
14575 EnclosingDecl->setInvalidDecl();
14577 } else if (FDTy->isIncompleteArrayType() && Record &&
14578 ((i + 1 == Fields.end() && !Record->isUnion()) ||
14579 ((getLangOpts().MicrosoftExt ||
14580 getLangOpts().CPlusPlus) &&
14581 (i + 1 == Fields.end() || Record->isUnion())))) {
14582 // Flexible array member.
14583 // Microsoft and g++ is more permissive regarding flexible array.
14584 // It will accept flexible array in union and also
14585 // as the sole element of a struct/class.
14586 unsigned DiagID = 0;
14587 if (Record->isUnion())
14588 DiagID = getLangOpts().MicrosoftExt
14589 ? diag::ext_flexible_array_union_ms
14590 : getLangOpts().CPlusPlus
14591 ? diag::ext_flexible_array_union_gnu
14592 : diag::err_flexible_array_union;
14593 else if (NumNamedMembers < 1)
14594 DiagID = getLangOpts().MicrosoftExt
14595 ? diag::ext_flexible_array_empty_aggregate_ms
14596 : getLangOpts().CPlusPlus
14597 ? diag::ext_flexible_array_empty_aggregate_gnu
14598 : diag::err_flexible_array_empty_aggregate;
14601 Diag(FD->getLocation(), DiagID) << FD->getDeclName()
14602 << Record->getTagKind();
14603 // While the layout of types that contain virtual bases is not specified
14604 // by the C++ standard, both the Itanium and Microsoft C++ ABIs place
14605 // virtual bases after the derived members. This would make a flexible
14606 // array member declared at the end of an object not adjacent to the end
14608 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record))
14609 if (RD->getNumVBases() != 0)
14610 Diag(FD->getLocation(), diag::err_flexible_array_virtual_base)
14611 << FD->getDeclName() << Record->getTagKind();
14612 if (!getLangOpts().C99)
14613 Diag(FD->getLocation(), diag::ext_c99_flexible_array_member)
14614 << FD->getDeclName() << Record->getTagKind();
14616 // If the element type has a non-trivial destructor, we would not
14617 // implicitly destroy the elements, so disallow it for now.
14619 // FIXME: GCC allows this. We should probably either implicitly delete
14620 // the destructor of the containing class, or just allow this.
14621 QualType BaseElem = Context.getBaseElementType(FD->getType());
14622 if (!BaseElem->isDependentType() && BaseElem.isDestructedType()) {
14623 Diag(FD->getLocation(), diag::err_flexible_array_has_nontrivial_dtor)
14624 << FD->getDeclName() << FD->getType();
14625 FD->setInvalidDecl();
14626 EnclosingDecl->setInvalidDecl();
14629 // Okay, we have a legal flexible array member at the end of the struct.
14630 Record->setHasFlexibleArrayMember(true);
14631 } else if (!FDTy->isDependentType() &&
14632 RequireCompleteType(FD->getLocation(), FD->getType(),
14633 diag::err_field_incomplete)) {
14635 FD->setInvalidDecl();
14636 EnclosingDecl->setInvalidDecl();
14638 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) {
14639 if (Record && FDTTy->getDecl()->hasFlexibleArrayMember()) {
14640 // A type which contains a flexible array member is considered to be a
14641 // flexible array member.
14642 Record->setHasFlexibleArrayMember(true);
14643 if (!Record->isUnion()) {
14644 // If this is a struct/class and this is not the last element, reject
14645 // it. Note that GCC supports variable sized arrays in the middle of
14647 if (i + 1 != Fields.end())
14648 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct)
14649 << FD->getDeclName() << FD->getType();
14651 // We support flexible arrays at the end of structs in
14652 // other structs as an extension.
14653 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct)
14654 << FD->getDeclName();
14658 if (isa<ObjCContainerDecl>(EnclosingDecl) &&
14659 RequireNonAbstractType(FD->getLocation(), FD->getType(),
14660 diag::err_abstract_type_in_decl,
14661 AbstractIvarType)) {
14662 // Ivars can not have abstract class types
14663 FD->setInvalidDecl();
14665 if (Record && FDTTy->getDecl()->hasObjectMember())
14666 Record->setHasObjectMember(true);
14667 if (Record && FDTTy->getDecl()->hasVolatileMember())
14668 Record->setHasVolatileMember(true);
14669 } else if (FDTy->isObjCObjectType()) {
14670 /// A field cannot be an Objective-c object
14671 Diag(FD->getLocation(), diag::err_statically_allocated_object)
14672 << FixItHint::CreateInsertion(FD->getLocation(), "*");
14673 QualType T = Context.getObjCObjectPointerType(FD->getType());
14675 } else if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
14676 Record && !ObjCFieldLifetimeErrReported &&
14677 (!getLangOpts().CPlusPlus || Record->isUnion())) {
14678 // It's an error in ARC or Weak if a field has lifetime.
14679 // We don't want to report this in a system header, though,
14680 // so we just make the field unavailable.
14681 // FIXME: that's really not sufficient; we need to make the type
14682 // itself invalid to, say, initialize or copy.
14683 QualType T = FD->getType();
14684 if (T.hasNonTrivialObjCLifetime()) {
14685 SourceLocation loc = FD->getLocation();
14686 if (getSourceManager().isInSystemHeader(loc)) {
14687 if (!FD->hasAttr<UnavailableAttr>()) {
14688 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
14689 UnavailableAttr::IR_ARCFieldWithOwnership, loc));
14692 Diag(FD->getLocation(), diag::err_arc_objc_object_in_tag)
14693 << T->isBlockPointerType() << Record->getTagKind();
14695 ObjCFieldLifetimeErrReported = true;
14697 } else if (getLangOpts().ObjC1 &&
14698 getLangOpts().getGC() != LangOptions::NonGC &&
14699 Record && !Record->hasObjectMember()) {
14700 if (FD->getType()->isObjCObjectPointerType() ||
14701 FD->getType().isObjCGCStrong())
14702 Record->setHasObjectMember(true);
14703 else if (Context.getAsArrayType(FD->getType())) {
14704 QualType BaseType = Context.getBaseElementType(FD->getType());
14705 if (BaseType->isRecordType() &&
14706 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember())
14707 Record->setHasObjectMember(true);
14708 else if (BaseType->isObjCObjectPointerType() ||
14709 BaseType.isObjCGCStrong())
14710 Record->setHasObjectMember(true);
14713 if (Record && FD->getType().isVolatileQualified())
14714 Record->setHasVolatileMember(true);
14715 // Keep track of the number of named members.
14716 if (FD->getIdentifier())
14720 // Okay, we successfully defined 'Record'.
14722 bool Completed = false;
14723 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
14724 if (!CXXRecord->isInvalidDecl()) {
14725 // Set access bits correctly on the directly-declared conversions.
14726 for (CXXRecordDecl::conversion_iterator
14727 I = CXXRecord->conversion_begin(),
14728 E = CXXRecord->conversion_end(); I != E; ++I)
14729 I.setAccess((*I)->getAccess());
14732 if (!CXXRecord->isDependentType()) {
14733 if (CXXRecord->hasUserDeclaredDestructor()) {
14734 // Adjust user-defined destructor exception spec.
14735 if (getLangOpts().CPlusPlus11)
14736 AdjustDestructorExceptionSpec(CXXRecord,
14737 CXXRecord->getDestructor());
14740 if (!CXXRecord->isInvalidDecl()) {
14741 // Add any implicitly-declared members to this class.
14742 AddImplicitlyDeclaredMembersToClass(CXXRecord);
14744 // If we have virtual base classes, we may end up finding multiple
14745 // final overriders for a given virtual function. Check for this
14747 if (CXXRecord->getNumVBases()) {
14748 CXXFinalOverriderMap FinalOverriders;
14749 CXXRecord->getFinalOverriders(FinalOverriders);
14751 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
14752 MEnd = FinalOverriders.end();
14754 for (OverridingMethods::iterator SO = M->second.begin(),
14755 SOEnd = M->second.end();
14756 SO != SOEnd; ++SO) {
14757 assert(SO->second.size() > 0 &&
14758 "Virtual function without overridding functions?");
14759 if (SO->second.size() == 1)
14762 // C++ [class.virtual]p2:
14763 // In a derived class, if a virtual member function of a base
14764 // class subobject has more than one final overrider the
14765 // program is ill-formed.
14766 Diag(Record->getLocation(), diag::err_multiple_final_overriders)
14767 << (const NamedDecl *)M->first << Record;
14768 Diag(M->first->getLocation(),
14769 diag::note_overridden_virtual_function);
14770 for (OverridingMethods::overriding_iterator
14771 OM = SO->second.begin(),
14772 OMEnd = SO->second.end();
14774 Diag(OM->Method->getLocation(), diag::note_final_overrider)
14775 << (const NamedDecl *)M->first << OM->Method->getParent();
14777 Record->setInvalidDecl();
14780 CXXRecord->completeDefinition(&FinalOverriders);
14788 Record->completeDefinition();
14790 // We may have deferred checking for a deleted destructor. Check now.
14791 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
14792 auto *Dtor = CXXRecord->getDestructor();
14793 if (Dtor && Dtor->isImplicit() &&
14794 ShouldDeleteSpecialMember(Dtor, CXXDestructor))
14795 SetDeclDeleted(Dtor, CXXRecord->getLocation());
14798 if (Record->hasAttrs()) {
14799 CheckAlignasUnderalignment(Record);
14801 if (const MSInheritanceAttr *IA = Record->getAttr<MSInheritanceAttr>())
14802 checkMSInheritanceAttrOnDefinition(cast<CXXRecordDecl>(Record),
14803 IA->getRange(), IA->getBestCase(),
14804 IA->getSemanticSpelling());
14807 // Check if the structure/union declaration is a type that can have zero
14808 // size in C. For C this is a language extension, for C++ it may cause
14809 // compatibility problems.
14810 bool CheckForZeroSize;
14811 if (!getLangOpts().CPlusPlus) {
14812 CheckForZeroSize = true;
14814 // For C++ filter out types that cannot be referenced in C code.
14815 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record);
14817 CXXRecord->getLexicalDeclContext()->isExternCContext() &&
14818 !CXXRecord->isDependentType() &&
14819 CXXRecord->isCLike();
14821 if (CheckForZeroSize) {
14822 bool ZeroSize = true;
14823 bool IsEmpty = true;
14824 unsigned NonBitFields = 0;
14825 for (RecordDecl::field_iterator I = Record->field_begin(),
14826 E = Record->field_end();
14827 (NonBitFields == 0 || ZeroSize) && I != E; ++I) {
14829 if (I->isUnnamedBitfield()) {
14830 if (I->getBitWidthValue(Context) > 0)
14834 QualType FieldType = I->getType();
14835 if (FieldType->isIncompleteType() ||
14836 !Context.getTypeSizeInChars(FieldType).isZero())
14841 // Empty structs are an extension in C (C99 6.7.2.1p7). They are
14842 // allowed in C++, but warn if its declaration is inside
14843 // extern "C" block.
14845 Diag(RecLoc, getLangOpts().CPlusPlus ?
14846 diag::warn_zero_size_struct_union_in_extern_c :
14847 diag::warn_zero_size_struct_union_compat)
14848 << IsEmpty << Record->isUnion() << (NonBitFields > 1);
14851 // Structs without named members are extension in C (C99 6.7.2.1p7),
14852 // but are accepted by GCC.
14853 if (NonBitFields == 0 && !getLangOpts().CPlusPlus) {
14854 Diag(RecLoc, IsEmpty ? diag::ext_empty_struct_union :
14855 diag::ext_no_named_members_in_struct_union)
14856 << Record->isUnion();
14860 ObjCIvarDecl **ClsFields =
14861 reinterpret_cast<ObjCIvarDecl**>(RecFields.data());
14862 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) {
14863 ID->setEndOfDefinitionLoc(RBrac);
14864 // Add ivar's to class's DeclContext.
14865 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
14866 ClsFields[i]->setLexicalDeclContext(ID);
14867 ID->addDecl(ClsFields[i]);
14869 // Must enforce the rule that ivars in the base classes may not be
14871 if (ID->getSuperClass())
14872 DiagnoseDuplicateIvars(ID, ID->getSuperClass());
14873 } else if (ObjCImplementationDecl *IMPDecl =
14874 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
14875 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl");
14876 for (unsigned I = 0, N = RecFields.size(); I != N; ++I)
14877 // Ivar declared in @implementation never belongs to the implementation.
14878 // Only it is in implementation's lexical context.
14879 ClsFields[I]->setLexicalDeclContext(IMPDecl);
14880 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac);
14881 IMPDecl->setIvarLBraceLoc(LBrac);
14882 IMPDecl->setIvarRBraceLoc(RBrac);
14883 } else if (ObjCCategoryDecl *CDecl =
14884 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
14885 // case of ivars in class extension; all other cases have been
14886 // reported as errors elsewhere.
14887 // FIXME. Class extension does not have a LocEnd field.
14888 // CDecl->setLocEnd(RBrac);
14889 // Add ivar's to class extension's DeclContext.
14890 // Diagnose redeclaration of private ivars.
14891 ObjCInterfaceDecl *IDecl = CDecl->getClassInterface();
14892 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
14894 if (const ObjCIvarDecl *ClsIvar =
14895 IDecl->getIvarDecl(ClsFields[i]->getIdentifier())) {
14896 Diag(ClsFields[i]->getLocation(),
14897 diag::err_duplicate_ivar_declaration);
14898 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
14901 for (const auto *Ext : IDecl->known_extensions()) {
14902 if (const ObjCIvarDecl *ClsExtIvar
14903 = Ext->getIvarDecl(ClsFields[i]->getIdentifier())) {
14904 Diag(ClsFields[i]->getLocation(),
14905 diag::err_duplicate_ivar_declaration);
14906 Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
14911 ClsFields[i]->setLexicalDeclContext(CDecl);
14912 CDecl->addDecl(ClsFields[i]);
14914 CDecl->setIvarLBraceLoc(LBrac);
14915 CDecl->setIvarRBraceLoc(RBrac);
14920 ProcessDeclAttributeList(S, Record, Attr);
14923 /// \brief Determine whether the given integral value is representable within
14924 /// the given type T.
14925 static bool isRepresentableIntegerValue(ASTContext &Context,
14926 llvm::APSInt &Value,
14928 assert(T->isIntegralType(Context) && "Integral type required!");
14929 unsigned BitWidth = Context.getIntWidth(T);
14931 if (Value.isUnsigned() || Value.isNonNegative()) {
14932 if (T->isSignedIntegerOrEnumerationType())
14934 return Value.getActiveBits() <= BitWidth;
14936 return Value.getMinSignedBits() <= BitWidth;
14939 // \brief Given an integral type, return the next larger integral type
14940 // (or a NULL type of no such type exists).
14941 static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) {
14942 // FIXME: Int128/UInt128 support, which also needs to be introduced into
14943 // enum checking below.
14944 assert(T->isIntegralType(Context) && "Integral type required!");
14945 const unsigned NumTypes = 4;
14946 QualType SignedIntegralTypes[NumTypes] = {
14947 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy
14949 QualType UnsignedIntegralTypes[NumTypes] = {
14950 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy,
14951 Context.UnsignedLongLongTy
14954 unsigned BitWidth = Context.getTypeSize(T);
14955 QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes
14956 : UnsignedIntegralTypes;
14957 for (unsigned I = 0; I != NumTypes; ++I)
14958 if (Context.getTypeSize(Types[I]) > BitWidth)
14964 EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum,
14965 EnumConstantDecl *LastEnumConst,
14966 SourceLocation IdLoc,
14967 IdentifierInfo *Id,
14969 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
14970 llvm::APSInt EnumVal(IntWidth);
14973 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue))
14977 Val = DefaultLvalueConversion(Val).get();
14980 if (Enum->isDependentType() || Val->isTypeDependent())
14981 EltTy = Context.DependentTy;
14983 SourceLocation ExpLoc;
14984 if (getLangOpts().CPlusPlus11 && Enum->isFixed() &&
14985 !getLangOpts().MSVCCompat) {
14986 // C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the
14987 // constant-expression in the enumerator-definition shall be a converted
14988 // constant expression of the underlying type.
14989 EltTy = Enum->getIntegerType();
14990 ExprResult Converted =
14991 CheckConvertedConstantExpression(Val, EltTy, EnumVal,
14993 if (Converted.isInvalid())
14996 Val = Converted.get();
14997 } else if (!Val->isValueDependent() &&
14998 !(Val = VerifyIntegerConstantExpression(Val,
14999 &EnumVal).get())) {
15000 // C99 6.7.2.2p2: Make sure we have an integer constant expression.
15002 if (Enum->isFixed()) {
15003 EltTy = Enum->getIntegerType();
15005 // In Obj-C and Microsoft mode, require the enumeration value to be
15006 // representable in the underlying type of the enumeration. In C++11,
15007 // we perform a non-narrowing conversion as part of converted constant
15008 // expression checking.
15009 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
15010 if (getLangOpts().MSVCCompat) {
15011 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy;
15012 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
15014 Diag(IdLoc, diag::err_enumerator_too_large) << EltTy;
15016 Val = ImpCastExprToType(Val, EltTy,
15017 EltTy->isBooleanType() ?
15018 CK_IntegralToBoolean : CK_IntegralCast)
15020 } else if (getLangOpts().CPlusPlus) {
15021 // C++11 [dcl.enum]p5:
15022 // If the underlying type is not fixed, the type of each enumerator
15023 // is the type of its initializing value:
15024 // - If an initializer is specified for an enumerator, the
15025 // initializing value has the same type as the expression.
15026 EltTy = Val->getType();
15029 // The expression that defines the value of an enumeration constant
15030 // shall be an integer constant expression that has a value
15031 // representable as an int.
15033 // Complain if the value is not representable in an int.
15034 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy))
15035 Diag(IdLoc, diag::ext_enum_value_not_int)
15036 << EnumVal.toString(10) << Val->getSourceRange()
15037 << (EnumVal.isUnsigned() || EnumVal.isNonNegative());
15038 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) {
15039 // Force the type of the expression to 'int'.
15040 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).get();
15042 EltTy = Val->getType();
15049 if (Enum->isDependentType())
15050 EltTy = Context.DependentTy;
15051 else if (!LastEnumConst) {
15052 // C++0x [dcl.enum]p5:
15053 // If the underlying type is not fixed, the type of each enumerator
15054 // is the type of its initializing value:
15055 // - If no initializer is specified for the first enumerator, the
15056 // initializing value has an unspecified integral type.
15058 // GCC uses 'int' for its unspecified integral type, as does
15060 if (Enum->isFixed()) {
15061 EltTy = Enum->getIntegerType();
15064 EltTy = Context.IntTy;
15067 // Assign the last value + 1.
15068 EnumVal = LastEnumConst->getInitVal();
15070 EltTy = LastEnumConst->getType();
15072 // Check for overflow on increment.
15073 if (EnumVal < LastEnumConst->getInitVal()) {
15074 // C++0x [dcl.enum]p5:
15075 // If the underlying type is not fixed, the type of each enumerator
15076 // is the type of its initializing value:
15078 // - Otherwise the type of the initializing value is the same as
15079 // the type of the initializing value of the preceding enumerator
15080 // unless the incremented value is not representable in that type,
15081 // in which case the type is an unspecified integral type
15082 // sufficient to contain the incremented value. If no such type
15083 // exists, the program is ill-formed.
15084 QualType T = getNextLargerIntegralType(Context, EltTy);
15085 if (T.isNull() || Enum->isFixed()) {
15086 // There is no integral type larger enough to represent this
15087 // value. Complain, then allow the value to wrap around.
15088 EnumVal = LastEnumConst->getInitVal();
15089 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2);
15091 if (Enum->isFixed())
15092 // When the underlying type is fixed, this is ill-formed.
15093 Diag(IdLoc, diag::err_enumerator_wrapped)
15094 << EnumVal.toString(10)
15097 Diag(IdLoc, diag::ext_enumerator_increment_too_large)
15098 << EnumVal.toString(10);
15103 // Retrieve the last enumerator's value, extent that type to the
15104 // type that is supposed to be large enough to represent the incremented
15105 // value, then increment.
15106 EnumVal = LastEnumConst->getInitVal();
15107 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
15108 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy));
15111 // If we're not in C++, diagnose the overflow of enumerator values,
15112 // which in C99 means that the enumerator value is not representable in
15113 // an int (C99 6.7.2.2p2). However, we support GCC's extension that
15114 // permits enumerator values that are representable in some larger
15116 if (!getLangOpts().CPlusPlus && !T.isNull())
15117 Diag(IdLoc, diag::warn_enum_value_overflow);
15118 } else if (!getLangOpts().CPlusPlus &&
15119 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
15120 // Enforce C99 6.7.2.2p2 even when we compute the next value.
15121 Diag(IdLoc, diag::ext_enum_value_not_int)
15122 << EnumVal.toString(10) << 1;
15127 if (!EltTy->isDependentType()) {
15128 // Make the enumerator value match the signedness and size of the
15129 // enumerator's type.
15130 EnumVal = EnumVal.extOrTrunc(Context.getIntWidth(EltTy));
15131 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
15134 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy,
15138 Sema::SkipBodyInfo Sema::shouldSkipAnonEnumBody(Scope *S, IdentifierInfo *II,
15139 SourceLocation IILoc) {
15140 if (!(getLangOpts().Modules || getLangOpts().ModulesLocalVisibility) ||
15141 !getLangOpts().CPlusPlus)
15142 return SkipBodyInfo();
15144 // We have an anonymous enum definition. Look up the first enumerator to
15145 // determine if we should merge the definition with an existing one and
15147 NamedDecl *PrevDecl = LookupSingleName(S, II, IILoc, LookupOrdinaryName,
15149 auto *PrevECD = dyn_cast_or_null<EnumConstantDecl>(PrevDecl);
15151 return SkipBodyInfo();
15153 EnumDecl *PrevED = cast<EnumDecl>(PrevECD->getDeclContext());
15155 if (!PrevED->getDeclName() && !hasVisibleDefinition(PrevED, &Hidden)) {
15157 Skip.Previous = Hidden;
15161 return SkipBodyInfo();
15164 Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst,
15165 SourceLocation IdLoc, IdentifierInfo *Id,
15166 AttributeList *Attr,
15167 SourceLocation EqualLoc, Expr *Val) {
15168 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl);
15169 EnumConstantDecl *LastEnumConst =
15170 cast_or_null<EnumConstantDecl>(lastEnumConst);
15172 // The scope passed in may not be a decl scope. Zip up the scope tree until
15173 // we find one that is.
15174 S = getNonFieldDeclScope(S);
15176 // Verify that there isn't already something declared with this name in this
15178 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName,
15180 if (PrevDecl && PrevDecl->isTemplateParameter()) {
15181 // Maybe we will complain about the shadowed template parameter.
15182 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl);
15183 // Just pretend that we didn't see the previous declaration.
15184 PrevDecl = nullptr;
15187 // C++ [class.mem]p15:
15188 // If T is the name of a class, then each of the following shall have a name
15189 // different from T:
15190 // - every enumerator of every member of class T that is an unscoped
15192 if (!TheEnumDecl->isScoped())
15193 DiagnoseClassNameShadow(TheEnumDecl->getDeclContext(),
15194 DeclarationNameInfo(Id, IdLoc));
15196 EnumConstantDecl *New =
15197 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val);
15202 // When in C++, we may get a TagDecl with the same name; in this case the
15203 // enum constant will 'hide' the tag.
15204 assert((getLangOpts().CPlusPlus || !isa<TagDecl>(PrevDecl)) &&
15205 "Received TagDecl when not in C++!");
15206 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S) &&
15207 shouldLinkPossiblyHiddenDecl(PrevDecl, New)) {
15208 if (isa<EnumConstantDecl>(PrevDecl))
15209 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id;
15211 Diag(IdLoc, diag::err_redefinition) << Id;
15212 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
15217 // Process attributes.
15218 if (Attr) ProcessDeclAttributeList(S, New, Attr);
15219 AddPragmaAttributes(S, New);
15221 // Register this decl in the current scope stack.
15222 New->setAccess(TheEnumDecl->getAccess());
15223 PushOnScopeChains(New, S);
15225 ActOnDocumentableDecl(New);
15230 // Returns true when the enum initial expression does not trigger the
15231 // duplicate enum warning. A few common cases are exempted as follows:
15232 // Element2 = Element1
15233 // Element2 = Element1 + 1
15234 // Element2 = Element1 - 1
15235 // Where Element2 and Element1 are from the same enum.
15236 static bool ValidDuplicateEnum(EnumConstantDecl *ECD, EnumDecl *Enum) {
15237 Expr *InitExpr = ECD->getInitExpr();
15240 InitExpr = InitExpr->IgnoreImpCasts();
15242 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(InitExpr)) {
15243 if (!BO->isAdditiveOp())
15245 IntegerLiteral *IL = dyn_cast<IntegerLiteral>(BO->getRHS());
15248 if (IL->getValue() != 1)
15251 InitExpr = BO->getLHS();
15254 // This checks if the elements are from the same enum.
15255 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InitExpr);
15259 EnumConstantDecl *EnumConstant = dyn_cast<EnumConstantDecl>(DRE->getDecl());
15263 if (cast<EnumDecl>(TagDecl::castFromDeclContext(ECD->getDeclContext())) !=
15273 bool isTombstoneOrEmptyKey;
15274 DupKey(int64_t val, bool isTombstoneOrEmptyKey)
15275 : val(val), isTombstoneOrEmptyKey(isTombstoneOrEmptyKey) {}
15278 static DupKey GetDupKey(const llvm::APSInt& Val) {
15279 return DupKey(Val.isSigned() ? Val.getSExtValue() : Val.getZExtValue(),
15283 struct DenseMapInfoDupKey {
15284 static DupKey getEmptyKey() { return DupKey(0, true); }
15285 static DupKey getTombstoneKey() { return DupKey(1, true); }
15286 static unsigned getHashValue(const DupKey Key) {
15287 return (unsigned)(Key.val * 37);
15289 static bool isEqual(const DupKey& LHS, const DupKey& RHS) {
15290 return LHS.isTombstoneOrEmptyKey == RHS.isTombstoneOrEmptyKey &&
15291 LHS.val == RHS.val;
15294 } // end anonymous namespace
15296 // Emits a warning when an element is implicitly set a value that
15297 // a previous element has already been set to.
15298 static void CheckForDuplicateEnumValues(Sema &S, ArrayRef<Decl *> Elements,
15300 QualType EnumType) {
15301 if (S.Diags.isIgnored(diag::warn_duplicate_enum_values, Enum->getLocation()))
15303 // Avoid anonymous enums
15304 if (!Enum->getIdentifier())
15307 // Only check for small enums.
15308 if (Enum->getNumPositiveBits() > 63 || Enum->getNumNegativeBits() > 64)
15311 typedef SmallVector<EnumConstantDecl *, 3> ECDVector;
15312 typedef SmallVector<ECDVector *, 3> DuplicatesVector;
15314 typedef llvm::PointerUnion<EnumConstantDecl*, ECDVector*> DeclOrVector;
15315 typedef llvm::DenseMap<DupKey, DeclOrVector, DenseMapInfoDupKey>
15318 DuplicatesVector DupVector;
15319 ValueToVectorMap EnumMap;
15321 // Populate the EnumMap with all values represented by enum constants without
15323 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15324 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]);
15326 // Null EnumConstantDecl means a previous diagnostic has been emitted for
15327 // this constant. Skip this enum since it may be ill-formed.
15332 if (ECD->getInitExpr())
15335 DupKey Key = GetDupKey(ECD->getInitVal());
15336 DeclOrVector &Entry = EnumMap[Key];
15338 // First time encountering this value.
15339 if (Entry.isNull())
15343 // Create vectors for any values that has duplicates.
15344 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15345 EnumConstantDecl *ECD = cast<EnumConstantDecl>(Elements[i]);
15346 if (!ValidDuplicateEnum(ECD, Enum))
15349 DupKey Key = GetDupKey(ECD->getInitVal());
15351 DeclOrVector& Entry = EnumMap[Key];
15352 if (Entry.isNull())
15355 if (EnumConstantDecl *D = Entry.dyn_cast<EnumConstantDecl*>()) {
15356 // Ensure constants are different.
15360 // Create new vector and push values onto it.
15361 ECDVector *Vec = new ECDVector();
15363 Vec->push_back(ECD);
15365 // Update entry to point to the duplicates vector.
15368 // Store the vector somewhere we can consult later for quick emission of
15370 DupVector.push_back(Vec);
15374 ECDVector *Vec = Entry.get<ECDVector*>();
15375 // Make sure constants are not added more than once.
15376 if (*Vec->begin() == ECD)
15379 Vec->push_back(ECD);
15382 // Emit diagnostics.
15383 for (DuplicatesVector::iterator DupVectorIter = DupVector.begin(),
15384 DupVectorEnd = DupVector.end();
15385 DupVectorIter != DupVectorEnd; ++DupVectorIter) {
15386 ECDVector *Vec = *DupVectorIter;
15387 assert(Vec->size() > 1 && "ECDVector should have at least 2 elements.");
15389 // Emit warning for one enum constant.
15390 ECDVector::iterator I = Vec->begin();
15391 S.Diag((*I)->getLocation(), diag::warn_duplicate_enum_values)
15392 << (*I)->getName() << (*I)->getInitVal().toString(10)
15393 << (*I)->getSourceRange();
15396 // Emit one note for each of the remaining enum constants with
15398 for (ECDVector::iterator E = Vec->end(); I != E; ++I)
15399 S.Diag((*I)->getLocation(), diag::note_duplicate_element)
15400 << (*I)->getName() << (*I)->getInitVal().toString(10)
15401 << (*I)->getSourceRange();
15406 bool Sema::IsValueInFlagEnum(const EnumDecl *ED, const llvm::APInt &Val,
15407 bool AllowMask) const {
15408 assert(ED->isClosedFlag() && "looking for value in non-flag or open enum");
15409 assert(ED->isCompleteDefinition() && "expected enum definition");
15411 auto R = FlagBitsCache.insert(std::make_pair(ED, llvm::APInt()));
15412 llvm::APInt &FlagBits = R.first->second;
15415 for (auto *E : ED->enumerators()) {
15416 const auto &EVal = E->getInitVal();
15417 // Only single-bit enumerators introduce new flag values.
15418 if (EVal.isPowerOf2())
15419 FlagBits = FlagBits.zextOrSelf(EVal.getBitWidth()) | EVal;
15423 // A value is in a flag enum if either its bits are a subset of the enum's
15424 // flag bits (the first condition) or we are allowing masks and the same is
15425 // true of its complement (the second condition). When masks are allowed, we
15426 // allow the common idiom of ~(enum1 | enum2) to be a valid enum value.
15428 // While it's true that any value could be used as a mask, the assumption is
15429 // that a mask will have all of the insignificant bits set. Anything else is
15430 // likely a logic error.
15431 llvm::APInt FlagMask = ~FlagBits.zextOrTrunc(Val.getBitWidth());
15432 return !(FlagMask & Val) || (AllowMask && !(FlagMask & ~Val));
15435 void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceRange BraceRange,
15437 ArrayRef<Decl *> Elements,
15438 Scope *S, AttributeList *Attr) {
15439 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX);
15440 QualType EnumType = Context.getTypeDeclType(Enum);
15443 ProcessDeclAttributeList(S, Enum, Attr);
15445 if (Enum->isDependentType()) {
15446 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15447 EnumConstantDecl *ECD =
15448 cast_or_null<EnumConstantDecl>(Elements[i]);
15449 if (!ECD) continue;
15451 ECD->setType(EnumType);
15454 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0);
15458 // TODO: If the result value doesn't fit in an int, it must be a long or long
15459 // long value. ISO C does not support this, but GCC does as an extension,
15461 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
15462 unsigned CharWidth = Context.getTargetInfo().getCharWidth();
15463 unsigned ShortWidth = Context.getTargetInfo().getShortWidth();
15465 // Verify that all the values are okay, compute the size of the values, and
15466 // reverse the list.
15467 unsigned NumNegativeBits = 0;
15468 unsigned NumPositiveBits = 0;
15470 // Keep track of whether all elements have type int.
15471 bool AllElementsInt = true;
15473 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15474 EnumConstantDecl *ECD =
15475 cast_or_null<EnumConstantDecl>(Elements[i]);
15476 if (!ECD) continue; // Already issued a diagnostic.
15478 const llvm::APSInt &InitVal = ECD->getInitVal();
15480 // Keep track of the size of positive and negative values.
15481 if (InitVal.isUnsigned() || InitVal.isNonNegative())
15482 NumPositiveBits = std::max(NumPositiveBits,
15483 (unsigned)InitVal.getActiveBits());
15485 NumNegativeBits = std::max(NumNegativeBits,
15486 (unsigned)InitVal.getMinSignedBits());
15488 // Keep track of whether every enum element has type int (very commmon).
15489 if (AllElementsInt)
15490 AllElementsInt = ECD->getType() == Context.IntTy;
15493 // Figure out the type that should be used for this enum.
15495 unsigned BestWidth;
15497 // C++0x N3000 [conv.prom]p3:
15498 // An rvalue of an unscoped enumeration type whose underlying
15499 // type is not fixed can be converted to an rvalue of the first
15500 // of the following types that can represent all the values of
15501 // the enumeration: int, unsigned int, long int, unsigned long
15502 // int, long long int, or unsigned long long int.
15504 // An identifier declared as an enumeration constant has type int.
15505 // The C99 rule is modified by a gcc extension
15506 QualType BestPromotionType;
15508 bool Packed = Enum->hasAttr<PackedAttr>();
15509 // -fshort-enums is the equivalent to specifying the packed attribute on all
15510 // enum definitions.
15511 if (LangOpts.ShortEnums)
15514 if (Enum->isFixed()) {
15515 BestType = Enum->getIntegerType();
15516 if (BestType->isPromotableIntegerType())
15517 BestPromotionType = Context.getPromotedIntegerType(BestType);
15519 BestPromotionType = BestType;
15521 BestWidth = Context.getIntWidth(BestType);
15523 else if (NumNegativeBits) {
15524 // If there is a negative value, figure out the smallest integer type (of
15525 // int/long/longlong) that fits.
15526 // If it's packed, check also if it fits a char or a short.
15527 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
15528 BestType = Context.SignedCharTy;
15529 BestWidth = CharWidth;
15530 } else if (Packed && NumNegativeBits <= ShortWidth &&
15531 NumPositiveBits < ShortWidth) {
15532 BestType = Context.ShortTy;
15533 BestWidth = ShortWidth;
15534 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
15535 BestType = Context.IntTy;
15536 BestWidth = IntWidth;
15538 BestWidth = Context.getTargetInfo().getLongWidth();
15540 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) {
15541 BestType = Context.LongTy;
15543 BestWidth = Context.getTargetInfo().getLongLongWidth();
15545 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth)
15546 Diag(Enum->getLocation(), diag::ext_enum_too_large);
15547 BestType = Context.LongLongTy;
15550 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType);
15552 // If there is no negative value, figure out the smallest type that fits
15553 // all of the enumerator values.
15554 // If it's packed, check also if it fits a char or a short.
15555 if (Packed && NumPositiveBits <= CharWidth) {
15556 BestType = Context.UnsignedCharTy;
15557 BestPromotionType = Context.IntTy;
15558 BestWidth = CharWidth;
15559 } else if (Packed && NumPositiveBits <= ShortWidth) {
15560 BestType = Context.UnsignedShortTy;
15561 BestPromotionType = Context.IntTy;
15562 BestWidth = ShortWidth;
15563 } else if (NumPositiveBits <= IntWidth) {
15564 BestType = Context.UnsignedIntTy;
15565 BestWidth = IntWidth;
15567 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
15568 ? Context.UnsignedIntTy : Context.IntTy;
15569 } else if (NumPositiveBits <=
15570 (BestWidth = Context.getTargetInfo().getLongWidth())) {
15571 BestType = Context.UnsignedLongTy;
15573 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
15574 ? Context.UnsignedLongTy : Context.LongTy;
15576 BestWidth = Context.getTargetInfo().getLongLongWidth();
15577 assert(NumPositiveBits <= BestWidth &&
15578 "How could an initializer get larger than ULL?");
15579 BestType = Context.UnsignedLongLongTy;
15581 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
15582 ? Context.UnsignedLongLongTy : Context.LongLongTy;
15586 // Loop over all of the enumerator constants, changing their types to match
15587 // the type of the enum if needed.
15588 for (auto *D : Elements) {
15589 auto *ECD = cast_or_null<EnumConstantDecl>(D);
15590 if (!ECD) continue; // Already issued a diagnostic.
15592 // Standard C says the enumerators have int type, but we allow, as an
15593 // extension, the enumerators to be larger than int size. If each
15594 // enumerator value fits in an int, type it as an int, otherwise type it the
15595 // same as the enumerator decl itself. This means that in "enum { X = 1U }"
15596 // that X has type 'int', not 'unsigned'.
15598 // Determine whether the value fits into an int.
15599 llvm::APSInt InitVal = ECD->getInitVal();
15601 // If it fits into an integer type, force it. Otherwise force it to match
15602 // the enum decl type.
15606 if (!getLangOpts().CPlusPlus &&
15607 !Enum->isFixed() &&
15608 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) {
15609 NewTy = Context.IntTy;
15610 NewWidth = IntWidth;
15612 } else if (ECD->getType() == BestType) {
15613 // Already the right type!
15614 if (getLangOpts().CPlusPlus)
15615 // C++ [dcl.enum]p4: Following the closing brace of an
15616 // enum-specifier, each enumerator has the type of its
15618 ECD->setType(EnumType);
15622 NewWidth = BestWidth;
15623 NewSign = BestType->isSignedIntegerOrEnumerationType();
15626 // Adjust the APSInt value.
15627 InitVal = InitVal.extOrTrunc(NewWidth);
15628 InitVal.setIsSigned(NewSign);
15629 ECD->setInitVal(InitVal);
15631 // Adjust the Expr initializer and type.
15632 if (ECD->getInitExpr() &&
15633 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType()))
15634 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy,
15636 ECD->getInitExpr(),
15637 /*base paths*/ nullptr,
15639 if (getLangOpts().CPlusPlus)
15640 // C++ [dcl.enum]p4: Following the closing brace of an
15641 // enum-specifier, each enumerator has the type of its
15643 ECD->setType(EnumType);
15645 ECD->setType(NewTy);
15648 Enum->completeDefinition(BestType, BestPromotionType,
15649 NumPositiveBits, NumNegativeBits);
15651 CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType);
15653 if (Enum->isClosedFlag()) {
15654 for (Decl *D : Elements) {
15655 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(D);
15656 if (!ECD) continue; // Already issued a diagnostic.
15658 llvm::APSInt InitVal = ECD->getInitVal();
15659 if (InitVal != 0 && !InitVal.isPowerOf2() &&
15660 !IsValueInFlagEnum(Enum, InitVal, true))
15661 Diag(ECD->getLocation(), diag::warn_flag_enum_constant_out_of_range)
15666 // Now that the enum type is defined, ensure it's not been underaligned.
15667 if (Enum->hasAttrs())
15668 CheckAlignasUnderalignment(Enum);
15671 Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr,
15672 SourceLocation StartLoc,
15673 SourceLocation EndLoc) {
15674 StringLiteral *AsmString = cast<StringLiteral>(expr);
15676 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext,
15677 AsmString, StartLoc,
15679 CurContext->addDecl(New);
15683 static void checkModuleImportContext(Sema &S, Module *M,
15684 SourceLocation ImportLoc, DeclContext *DC,
15685 bool FromInclude = false) {
15686 SourceLocation ExternCLoc;
15688 if (auto *LSD = dyn_cast<LinkageSpecDecl>(DC)) {
15689 switch (LSD->getLanguage()) {
15690 case LinkageSpecDecl::lang_c:
15691 if (ExternCLoc.isInvalid())
15692 ExternCLoc = LSD->getLocStart();
15694 case LinkageSpecDecl::lang_cxx:
15697 DC = LSD->getParent();
15700 while (isa<LinkageSpecDecl>(DC))
15701 DC = DC->getParent();
15703 if (!isa<TranslationUnitDecl>(DC)) {
15704 S.Diag(ImportLoc, (FromInclude && S.isModuleVisible(M))
15705 ? diag::ext_module_import_not_at_top_level_noop
15706 : diag::err_module_import_not_at_top_level_fatal)
15707 << M->getFullModuleName() << DC;
15708 S.Diag(cast<Decl>(DC)->getLocStart(),
15709 diag::note_module_import_not_at_top_level) << DC;
15710 } else if (!M->IsExternC && ExternCLoc.isValid()) {
15711 S.Diag(ImportLoc, diag::ext_module_import_in_extern_c)
15712 << M->getFullModuleName();
15713 S.Diag(ExternCLoc, diag::note_extern_c_begins_here);
15717 Sema::DeclGroupPtrTy Sema::ActOnModuleDecl(SourceLocation StartLoc,
15718 SourceLocation ModuleLoc,
15719 ModuleDeclKind MDK,
15720 ModuleIdPath Path) {
15721 // A module implementation unit requires that we are not compiling a module
15722 // of any kind. A module interface unit requires that we are not compiling a
15724 switch (getLangOpts().getCompilingModule()) {
15725 case LangOptions::CMK_None:
15726 // It's OK to compile a module interface as a normal translation unit.
15729 case LangOptions::CMK_ModuleInterface:
15730 if (MDK != ModuleDeclKind::Implementation)
15733 // We were asked to compile a module interface unit but this is a module
15734 // implementation unit. That indicates the 'export' is missing.
15735 Diag(ModuleLoc, diag::err_module_interface_implementation_mismatch)
15736 << FixItHint::CreateInsertion(ModuleLoc, "export ");
15739 case LangOptions::CMK_ModuleMap:
15740 Diag(ModuleLoc, diag::err_module_decl_in_module_map_module);
15744 // FIXME: Create a ModuleDecl and return it.
15746 // FIXME: Most of this work should be done by the preprocessor rather than
15747 // here, in order to support macro import.
15749 // Flatten the dots in a module name. Unlike Clang's hierarchical module map
15750 // modules, the dots here are just another character that can appear in a
15752 std::string ModuleName;
15753 for (auto &Piece : Path) {
15754 if (!ModuleName.empty())
15756 ModuleName += Piece.first->getName();
15759 // If a module name was explicitly specified on the command line, it must be
15761 if (!getLangOpts().CurrentModule.empty() &&
15762 getLangOpts().CurrentModule != ModuleName) {
15763 Diag(Path.front().second, diag::err_current_module_name_mismatch)
15764 << SourceRange(Path.front().second, Path.back().second)
15765 << getLangOpts().CurrentModule;
15768 const_cast<LangOptions&>(getLangOpts()).CurrentModule = ModuleName;
15770 auto &Map = PP.getHeaderSearchInfo().getModuleMap();
15773 case ModuleDeclKind::Module: {
15774 // FIXME: Check we're not in a submodule.
15776 // We can't have parsed or imported a definition of this module or parsed a
15777 // module map defining it already.
15778 if (auto *M = Map.findModule(ModuleName)) {
15779 Diag(Path[0].second, diag::err_module_redefinition) << ModuleName;
15780 if (M->DefinitionLoc.isValid())
15781 Diag(M->DefinitionLoc, diag::note_prev_module_definition);
15782 else if (const auto *FE = M->getASTFile())
15783 Diag(M->DefinitionLoc, diag::note_prev_module_definition_from_ast_file)
15788 // Create a Module for the module that we're defining.
15789 Module *Mod = Map.createModuleForInterfaceUnit(ModuleLoc, ModuleName);
15790 assert(Mod && "module creation should not fail");
15792 // Enter the semantic scope of the module.
15793 ActOnModuleBegin(ModuleLoc, Mod);
15797 case ModuleDeclKind::Partition:
15798 // FIXME: Check we are in a submodule of the named module.
15801 case ModuleDeclKind::Implementation:
15802 std::pair<IdentifierInfo *, SourceLocation> ModuleNameLoc(
15803 PP.getIdentifierInfo(ModuleName), Path[0].second);
15805 DeclResult Import = ActOnModuleImport(ModuleLoc, ModuleLoc, ModuleNameLoc);
15806 if (Import.isInvalid())
15808 return ConvertDeclToDeclGroup(Import.get());
15811 llvm_unreachable("unexpected module decl kind");
15814 DeclResult Sema::ActOnModuleImport(SourceLocation StartLoc,
15815 SourceLocation ImportLoc,
15816 ModuleIdPath Path) {
15818 getModuleLoader().loadModule(ImportLoc, Path, Module::AllVisible,
15819 /*IsIncludeDirective=*/false);
15823 VisibleModules.setVisible(Mod, ImportLoc);
15825 checkModuleImportContext(*this, Mod, ImportLoc, CurContext);
15827 // FIXME: we should support importing a submodule within a different submodule
15828 // of the same top-level module. Until we do, make it an error rather than
15829 // silently ignoring the import.
15830 // Import-from-implementation is valid in the Modules TS. FIXME: Should we
15831 // warn on a redundant import of the current module?
15832 if (Mod->getTopLevelModuleName() == getLangOpts().CurrentModule &&
15833 (getLangOpts().isCompilingModule() || !getLangOpts().ModulesTS))
15834 Diag(ImportLoc, getLangOpts().isCompilingModule()
15835 ? diag::err_module_self_import
15836 : diag::err_module_import_in_implementation)
15837 << Mod->getFullModuleName() << getLangOpts().CurrentModule;
15839 SmallVector<SourceLocation, 2> IdentifierLocs;
15840 Module *ModCheck = Mod;
15841 for (unsigned I = 0, N = Path.size(); I != N; ++I) {
15842 // If we've run out of module parents, just drop the remaining identifiers.
15843 // We need the length to be consistent.
15846 ModCheck = ModCheck->Parent;
15848 IdentifierLocs.push_back(Path[I].second);
15851 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15852 ImportDecl *Import = ImportDecl::Create(Context, TU, StartLoc,
15853 Mod, IdentifierLocs);
15854 if (!ModuleScopes.empty())
15855 Context.addModuleInitializer(ModuleScopes.back().Module, Import);
15856 TU->addDecl(Import);
15860 void Sema::ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
15861 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext, true);
15862 BuildModuleInclude(DirectiveLoc, Mod);
15865 void Sema::BuildModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
15866 // Determine whether we're in the #include buffer for a module. The #includes
15867 // in that buffer do not qualify as module imports; they're just an
15868 // implementation detail of us building the module.
15870 // FIXME: Should we even get ActOnModuleInclude calls for those?
15871 bool IsInModuleIncludes =
15872 TUKind == TU_Module &&
15873 getSourceManager().isWrittenInMainFile(DirectiveLoc);
15875 bool ShouldAddImport = !IsInModuleIncludes;
15877 // If this module import was due to an inclusion directive, create an
15878 // implicit import declaration to capture it in the AST.
15879 if (ShouldAddImport) {
15880 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15881 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
15884 if (!ModuleScopes.empty())
15885 Context.addModuleInitializer(ModuleScopes.back().Module, ImportD);
15886 TU->addDecl(ImportD);
15887 Consumer.HandleImplicitImportDecl(ImportD);
15890 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, DirectiveLoc);
15891 VisibleModules.setVisible(Mod, DirectiveLoc);
15894 void Sema::ActOnModuleBegin(SourceLocation DirectiveLoc, Module *Mod) {
15895 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext, true);
15897 ModuleScopes.push_back({});
15898 ModuleScopes.back().Module = Mod;
15899 if (getLangOpts().ModulesLocalVisibility)
15900 ModuleScopes.back().OuterVisibleModules = std::move(VisibleModules);
15902 VisibleModules.setVisible(Mod, DirectiveLoc);
15905 void Sema::ActOnModuleEnd(SourceLocation EofLoc, Module *Mod) {
15906 if (getLangOpts().ModulesLocalVisibility) {
15907 VisibleModules = std::move(ModuleScopes.back().OuterVisibleModules);
15908 // Leaving a module hides namespace names, so our visible namespace cache
15909 // is now out of date.
15910 VisibleNamespaceCache.clear();
15913 assert(!ModuleScopes.empty() && ModuleScopes.back().Module == Mod &&
15914 "left the wrong module scope");
15915 ModuleScopes.pop_back();
15917 // We got to the end of processing a #include of a local module. Create an
15918 // ImportDecl as we would for an imported module.
15919 FileID File = getSourceManager().getFileID(EofLoc);
15920 assert(File != getSourceManager().getMainFileID() &&
15921 "end of submodule in main source file");
15922 SourceLocation DirectiveLoc = getSourceManager().getIncludeLoc(File);
15923 BuildModuleInclude(DirectiveLoc, Mod);
15926 void Sema::createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
15928 // Bail if we're not allowed to implicitly import a module here.
15929 if (isSFINAEContext() || !getLangOpts().ModulesErrorRecovery)
15932 // Create the implicit import declaration.
15933 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15934 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
15936 TU->addDecl(ImportD);
15937 Consumer.HandleImplicitImportDecl(ImportD);
15939 // Make the module visible.
15940 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, Loc);
15941 VisibleModules.setVisible(Mod, Loc);
15944 /// We have parsed the start of an export declaration, including the '{'
15946 Decl *Sema::ActOnStartExportDecl(Scope *S, SourceLocation ExportLoc,
15947 SourceLocation LBraceLoc) {
15948 ExportDecl *D = ExportDecl::Create(Context, CurContext, ExportLoc);
15950 // C++ Modules TS draft:
15951 // An export-declaration shall appear in the purview of a module other than
15952 // the global module.
15953 if (ModuleScopes.empty() || !ModuleScopes.back().Module ||
15954 ModuleScopes.back().Module->Kind != Module::ModuleInterfaceUnit)
15955 Diag(ExportLoc, diag::err_export_not_in_module_interface);
15957 // An export-declaration [...] shall not contain more than one
15960 // The intent here is that an export-declaration cannot appear within another
15961 // export-declaration.
15962 if (D->isExported())
15963 Diag(ExportLoc, diag::err_export_within_export);
15965 CurContext->addDecl(D);
15966 PushDeclContext(S, D);
15970 /// Complete the definition of an export declaration.
15971 Decl *Sema::ActOnFinishExportDecl(Scope *S, Decl *D, SourceLocation RBraceLoc) {
15972 auto *ED = cast<ExportDecl>(D);
15973 if (RBraceLoc.isValid())
15974 ED->setRBraceLoc(RBraceLoc);
15976 // FIXME: Diagnose export of internal-linkage declaration (including
15977 // anonymous namespace).
15983 void Sema::ActOnPragmaRedefineExtname(IdentifierInfo* Name,
15984 IdentifierInfo* AliasName,
15985 SourceLocation PragmaLoc,
15986 SourceLocation NameLoc,
15987 SourceLocation AliasNameLoc) {
15988 NamedDecl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc,
15989 LookupOrdinaryName);
15990 AsmLabelAttr *Attr =
15991 AsmLabelAttr::CreateImplicit(Context, AliasName->getName(), AliasNameLoc);
15993 // If a declaration that:
15994 // 1) declares a function or a variable
15995 // 2) has external linkage
15996 // already exists, add a label attribute to it.
15997 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
15998 if (isDeclExternC(PrevDecl))
15999 PrevDecl->addAttr(Attr);
16001 Diag(PrevDecl->getLocation(), diag::warn_redefine_extname_not_applied)
16002 << /*Variable*/(isa<FunctionDecl>(PrevDecl) ? 0 : 1) << PrevDecl;
16003 // Otherwise, add a label atttibute to ExtnameUndeclaredIdentifiers.
16005 (void)ExtnameUndeclaredIdentifiers.insert(std::make_pair(Name, Attr));
16008 void Sema::ActOnPragmaWeakID(IdentifierInfo* Name,
16009 SourceLocation PragmaLoc,
16010 SourceLocation NameLoc) {
16011 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName);
16014 PrevDecl->addAttr(WeakAttr::CreateImplicit(Context, PragmaLoc));
16016 (void)WeakUndeclaredIdentifiers.insert(
16017 std::pair<IdentifierInfo*,WeakInfo>
16018 (Name, WeakInfo((IdentifierInfo*)nullptr, NameLoc)));
16022 void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name,
16023 IdentifierInfo* AliasName,
16024 SourceLocation PragmaLoc,
16025 SourceLocation NameLoc,
16026 SourceLocation AliasNameLoc) {
16027 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc,
16028 LookupOrdinaryName);
16029 WeakInfo W = WeakInfo(Name, NameLoc);
16031 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
16032 if (!PrevDecl->hasAttr<AliasAttr>())
16033 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl))
16034 DeclApplyPragmaWeak(TUScope, ND, W);
16036 (void)WeakUndeclaredIdentifiers.insert(
16037 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W));
16041 Decl *Sema::getObjCDeclContext() const {
16042 return (dyn_cast_or_null<ObjCContainerDecl>(CurContext));