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_returns_retained_mismatch);
2955 Diag(OldLocation, diag::note_previous_declaration);
2959 NewTypeInfo = NewTypeInfo.withProducesResult(true);
2960 RequiresAdjustment = true;
2963 if (RequiresAdjustment) {
2964 const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>();
2965 AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo);
2966 New->setType(QualType(AdjustedType, 0));
2967 NewQType = Context.getCanonicalType(New->getType());
2968 NewType = cast<FunctionType>(NewQType);
2971 // If this redeclaration makes the function inline, we may need to add it to
2972 // UndefinedButUsed.
2973 if (!Old->isInlined() && New->isInlined() &&
2974 !New->hasAttr<GNUInlineAttr>() &&
2975 !getLangOpts().GNUInline &&
2976 Old->isUsed(false) &&
2977 !Old->isDefined() && !New->isThisDeclarationADefinition())
2978 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
2981 // If this redeclaration makes it newly gnu_inline, we don't want to warn
2983 if (New->hasAttr<GNUInlineAttr>() &&
2984 Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) {
2985 UndefinedButUsed.erase(Old->getCanonicalDecl());
2988 // If pass_object_size params don't match up perfectly, this isn't a valid
2990 if (Old->getNumParams() > 0 && Old->getNumParams() == New->getNumParams() &&
2991 !hasIdenticalPassObjectSizeAttrs(Old, New)) {
2992 Diag(New->getLocation(), diag::err_different_pass_object_size_params)
2993 << New->getDeclName();
2994 Diag(OldLocation, PrevDiag) << Old << Old->getType();
2998 if (getLangOpts().CPlusPlus) {
2999 // C++1z [over.load]p2
3000 // Certain function declarations cannot be overloaded:
3001 // -- Function declarations that differ only in the return type,
3002 // the exception specification, or both cannot be overloaded.
3004 // Check the exception specifications match. This may recompute the type of
3005 // both Old and New if it resolved exception specifications, so grab the
3006 // types again after this. Because this updates the type, we do this before
3007 // any of the other checks below, which may update the "de facto" NewQType
3008 // but do not necessarily update the type of New.
3009 if (CheckEquivalentExceptionSpec(Old, New))
3011 OldQType = Context.getCanonicalType(Old->getType());
3012 NewQType = Context.getCanonicalType(New->getType());
3014 // Go back to the type source info to compare the declared return types,
3015 // per C++1y [dcl.type.auto]p13:
3016 // Redeclarations or specializations of a function or function template
3017 // with a declared return type that uses a placeholder type shall also
3018 // use that placeholder, not a deduced type.
3019 QualType OldDeclaredReturnType =
3020 (Old->getTypeSourceInfo()
3021 ? Old->getTypeSourceInfo()->getType()->castAs<FunctionType>()
3022 : OldType)->getReturnType();
3023 QualType NewDeclaredReturnType =
3024 (New->getTypeSourceInfo()
3025 ? New->getTypeSourceInfo()->getType()->castAs<FunctionType>()
3026 : NewType)->getReturnType();
3027 if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType) &&
3028 !((NewQType->isDependentType() || OldQType->isDependentType()) &&
3029 New->isLocalExternDecl())) {
3031 if (NewDeclaredReturnType->isObjCObjectPointerType() &&
3032 OldDeclaredReturnType->isObjCObjectPointerType())
3033 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType);
3034 if (ResQT.isNull()) {
3035 if (New->isCXXClassMember() && New->isOutOfLine())
3036 Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type)
3037 << New << New->getReturnTypeSourceRange();
3039 Diag(New->getLocation(), diag::err_ovl_diff_return_type)
3040 << New->getReturnTypeSourceRange();
3041 Diag(OldLocation, PrevDiag) << Old << Old->getType()
3042 << Old->getReturnTypeSourceRange();
3049 QualType OldReturnType = OldType->getReturnType();
3050 QualType NewReturnType = cast<FunctionType>(NewQType)->getReturnType();
3051 if (OldReturnType != NewReturnType) {
3052 // If this function has a deduced return type and has already been
3053 // defined, copy the deduced value from the old declaration.
3054 AutoType *OldAT = Old->getReturnType()->getContainedAutoType();
3055 if (OldAT && OldAT->isDeduced()) {
3057 SubstAutoType(New->getType(),
3058 OldAT->isDependentType() ? Context.DependentTy
3059 : OldAT->getDeducedType()));
3060 NewQType = Context.getCanonicalType(
3061 SubstAutoType(NewQType,
3062 OldAT->isDependentType() ? Context.DependentTy
3063 : OldAT->getDeducedType()));
3067 const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
3068 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
3069 if (OldMethod && NewMethod) {
3070 // Preserve triviality.
3071 NewMethod->setTrivial(OldMethod->isTrivial());
3073 // MSVC allows explicit template specialization at class scope:
3074 // 2 CXXMethodDecls referring to the same function will be injected.
3075 // We don't want a redeclaration error.
3076 bool IsClassScopeExplicitSpecialization =
3077 OldMethod->isFunctionTemplateSpecialization() &&
3078 NewMethod->isFunctionTemplateSpecialization();
3079 bool isFriend = NewMethod->getFriendObjectKind();
3081 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() &&
3082 !IsClassScopeExplicitSpecialization) {
3083 // -- Member function declarations with the same name and the
3084 // same parameter types cannot be overloaded if any of them
3085 // is a static member function declaration.
3086 if (OldMethod->isStatic() != NewMethod->isStatic()) {
3087 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
3088 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3092 // C++ [class.mem]p1:
3093 // [...] A member shall not be declared twice in the
3094 // member-specification, except that a nested class or member
3095 // class template can be declared and then later defined.
3096 if (!inTemplateInstantiation()) {
3098 if (isa<CXXConstructorDecl>(OldMethod))
3099 NewDiag = diag::err_constructor_redeclared;
3100 else if (isa<CXXDestructorDecl>(NewMethod))
3101 NewDiag = diag::err_destructor_redeclared;
3102 else if (isa<CXXConversionDecl>(NewMethod))
3103 NewDiag = diag::err_conv_function_redeclared;
3105 NewDiag = diag::err_member_redeclared;
3107 Diag(New->getLocation(), NewDiag);
3109 Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation)
3110 << New << New->getType();
3112 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3115 // Complain if this is an explicit declaration of a special
3116 // member that was initially declared implicitly.
3118 // As an exception, it's okay to befriend such methods in order
3119 // to permit the implicit constructor/destructor/operator calls.
3120 } else if (OldMethod->isImplicit()) {
3122 NewMethod->setImplicit();
3124 Diag(NewMethod->getLocation(),
3125 diag::err_definition_of_implicitly_declared_member)
3126 << New << getSpecialMember(OldMethod);
3129 } else if (OldMethod->getFirstDecl()->isExplicitlyDefaulted() && !isFriend) {
3130 Diag(NewMethod->getLocation(),
3131 diag::err_definition_of_explicitly_defaulted_member)
3132 << getSpecialMember(OldMethod);
3137 // C++11 [dcl.attr.noreturn]p1:
3138 // The first declaration of a function shall specify the noreturn
3139 // attribute if any declaration of that function specifies the noreturn
3141 const CXX11NoReturnAttr *NRA = New->getAttr<CXX11NoReturnAttr>();
3142 if (NRA && !Old->hasAttr<CXX11NoReturnAttr>()) {
3143 Diag(NRA->getLocation(), diag::err_noreturn_missing_on_first_decl);
3144 Diag(Old->getFirstDecl()->getLocation(),
3145 diag::note_noreturn_missing_first_decl);
3148 // C++11 [dcl.attr.depend]p2:
3149 // The first declaration of a function shall specify the
3150 // carries_dependency attribute for its declarator-id if any declaration
3151 // of the function specifies the carries_dependency attribute.
3152 const CarriesDependencyAttr *CDA = New->getAttr<CarriesDependencyAttr>();
3153 if (CDA && !Old->hasAttr<CarriesDependencyAttr>()) {
3154 Diag(CDA->getLocation(),
3155 diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/;
3156 Diag(Old->getFirstDecl()->getLocation(),
3157 diag::note_carries_dependency_missing_first_decl) << 0/*Function*/;
3161 // All declarations for a function shall agree exactly in both the
3162 // return type and the parameter-type-list.
3163 // We also want to respect all the extended bits except noreturn.
3165 // noreturn should now match unless the old type info didn't have it.
3166 QualType OldQTypeForComparison = OldQType;
3167 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) {
3168 auto *OldType = OldQType->castAs<FunctionProtoType>();
3169 const FunctionType *OldTypeForComparison
3170 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true));
3171 OldQTypeForComparison = QualType(OldTypeForComparison, 0);
3172 assert(OldQTypeForComparison.isCanonical());
3175 if (haveIncompatibleLanguageLinkages(Old, New)) {
3176 // As a special case, retain the language linkage from previous
3177 // declarations of a friend function as an extension.
3179 // This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC
3180 // and is useful because there's otherwise no way to specify language
3181 // linkage within class scope.
3183 // Check cautiously as the friend object kind isn't yet complete.
3184 if (New->getFriendObjectKind() != Decl::FOK_None) {
3185 Diag(New->getLocation(), diag::ext_retained_language_linkage) << New;
3186 Diag(OldLocation, PrevDiag);
3188 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3189 Diag(OldLocation, PrevDiag);
3194 if (OldQTypeForComparison == NewQType)
3195 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3197 if ((NewQType->isDependentType() || OldQType->isDependentType()) &&
3198 New->isLocalExternDecl()) {
3199 // It's OK if we couldn't merge types for a local function declaraton
3200 // if either the old or new type is dependent. We'll merge the types
3201 // when we instantiate the function.
3205 // Fall through for conflicting redeclarations and redefinitions.
3208 // C: Function types need to be compatible, not identical. This handles
3209 // duplicate function decls like "void f(int); void f(enum X);" properly.
3210 if (!getLangOpts().CPlusPlus &&
3211 Context.typesAreCompatible(OldQType, NewQType)) {
3212 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>();
3213 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>();
3214 const FunctionProtoType *OldProto = nullptr;
3215 if (MergeTypeWithOld && isa<FunctionNoProtoType>(NewFuncType) &&
3216 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) {
3217 // The old declaration provided a function prototype, but the
3218 // new declaration does not. Merge in the prototype.
3219 assert(!OldProto->hasExceptionSpec() && "Exception spec in C");
3220 SmallVector<QualType, 16> ParamTypes(OldProto->param_types());
3222 Context.getFunctionType(NewFuncType->getReturnType(), ParamTypes,
3223 OldProto->getExtProtoInfo());
3224 New->setType(NewQType);
3225 New->setHasInheritedPrototype();
3227 // Synthesize parameters with the same types.
3228 SmallVector<ParmVarDecl*, 16> Params;
3229 for (const auto &ParamType : OldProto->param_types()) {
3230 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(),
3231 SourceLocation(), nullptr,
3232 ParamType, /*TInfo=*/nullptr,
3234 Param->setScopeInfo(0, Params.size());
3235 Param->setImplicit();
3236 Params.push_back(Param);
3239 New->setParams(Params);
3242 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3245 // GNU C permits a K&R definition to follow a prototype declaration
3246 // if the declared types of the parameters in the K&R definition
3247 // match the types in the prototype declaration, even when the
3248 // promoted types of the parameters from the K&R definition differ
3249 // from the types in the prototype. GCC then keeps the types from
3252 // If a variadic prototype is followed by a non-variadic K&R definition,
3253 // the K&R definition becomes variadic. This is sort of an edge case, but
3254 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and
3256 if (!getLangOpts().CPlusPlus &&
3257 Old->hasPrototype() && !New->hasPrototype() &&
3258 New->getType()->getAs<FunctionProtoType>() &&
3259 Old->getNumParams() == New->getNumParams()) {
3260 SmallVector<QualType, 16> ArgTypes;
3261 SmallVector<GNUCompatibleParamWarning, 16> Warnings;
3262 const FunctionProtoType *OldProto
3263 = Old->getType()->getAs<FunctionProtoType>();
3264 const FunctionProtoType *NewProto
3265 = New->getType()->getAs<FunctionProtoType>();
3267 // Determine whether this is the GNU C extension.
3268 QualType MergedReturn = Context.mergeTypes(OldProto->getReturnType(),
3269 NewProto->getReturnType());
3270 bool LooseCompatible = !MergedReturn.isNull();
3271 for (unsigned Idx = 0, End = Old->getNumParams();
3272 LooseCompatible && Idx != End; ++Idx) {
3273 ParmVarDecl *OldParm = Old->getParamDecl(Idx);
3274 ParmVarDecl *NewParm = New->getParamDecl(Idx);
3275 if (Context.typesAreCompatible(OldParm->getType(),
3276 NewProto->getParamType(Idx))) {
3277 ArgTypes.push_back(NewParm->getType());
3278 } else if (Context.typesAreCompatible(OldParm->getType(),
3280 /*CompareUnqualified=*/true)) {
3281 GNUCompatibleParamWarning Warn = { OldParm, NewParm,
3282 NewProto->getParamType(Idx) };
3283 Warnings.push_back(Warn);
3284 ArgTypes.push_back(NewParm->getType());
3286 LooseCompatible = false;
3289 if (LooseCompatible) {
3290 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) {
3291 Diag(Warnings[Warn].NewParm->getLocation(),
3292 diag::ext_param_promoted_not_compatible_with_prototype)
3293 << Warnings[Warn].PromotedType
3294 << Warnings[Warn].OldParm->getType();
3295 if (Warnings[Warn].OldParm->getLocation().isValid())
3296 Diag(Warnings[Warn].OldParm->getLocation(),
3297 diag::note_previous_declaration);
3300 if (MergeTypeWithOld)
3301 New->setType(Context.getFunctionType(MergedReturn, ArgTypes,
3302 OldProto->getExtProtoInfo()));
3303 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3306 // Fall through to diagnose conflicting types.
3309 // A function that has already been declared has been redeclared or
3310 // defined with a different type; show an appropriate diagnostic.
3312 // If the previous declaration was an implicitly-generated builtin
3313 // declaration, then at the very least we should use a specialized note.
3315 if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) {
3316 // If it's actually a library-defined builtin function like 'malloc'
3317 // or 'printf', just warn about the incompatible redeclaration.
3318 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) {
3319 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New;
3320 Diag(OldLocation, diag::note_previous_builtin_declaration)
3321 << Old << Old->getType();
3323 // If this is a global redeclaration, just forget hereafter
3324 // about the "builtin-ness" of the function.
3326 // Doing this for local extern declarations is problematic. If
3327 // the builtin declaration remains visible, a second invalid
3328 // local declaration will produce a hard error; if it doesn't
3329 // remain visible, a single bogus local redeclaration (which is
3330 // actually only a warning) could break all the downstream code.
3331 if (!New->getLexicalDeclContext()->isFunctionOrMethod())
3332 New->getIdentifier()->revertBuiltin();
3337 PrevDiag = diag::note_previous_builtin_declaration;
3340 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName();
3341 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3345 /// \brief Completes the merge of two function declarations that are
3346 /// known to be compatible.
3348 /// This routine handles the merging of attributes and other
3349 /// properties of function declarations from the old declaration to
3350 /// the new declaration, once we know that New is in fact a
3351 /// redeclaration of Old.
3354 bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
3355 Scope *S, bool MergeTypeWithOld) {
3356 // Merge the attributes
3357 mergeDeclAttributes(New, Old);
3359 // Merge "pure" flag.
3363 // Merge "used" flag.
3364 if (Old->getMostRecentDecl()->isUsed(false))
3367 // Merge attributes from the parameters. These can mismatch with K&R
3369 if (New->getNumParams() == Old->getNumParams())
3370 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) {
3371 ParmVarDecl *NewParam = New->getParamDecl(i);
3372 ParmVarDecl *OldParam = Old->getParamDecl(i);
3373 mergeParamDeclAttributes(NewParam, OldParam, *this);
3374 mergeParamDeclTypes(NewParam, OldParam, *this);
3377 if (getLangOpts().CPlusPlus)
3378 return MergeCXXFunctionDecl(New, Old, S);
3380 // Merge the function types so the we get the composite types for the return
3381 // and argument types. Per C11 6.2.7/4, only update the type if the old decl
3383 QualType Merged = Context.mergeTypes(Old->getType(), New->getType());
3384 if (!Merged.isNull() && MergeTypeWithOld)
3385 New->setType(Merged);
3390 void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod,
3391 ObjCMethodDecl *oldMethod) {
3392 // Merge the attributes, including deprecated/unavailable
3393 AvailabilityMergeKind MergeKind =
3394 isa<ObjCProtocolDecl>(oldMethod->getDeclContext())
3395 ? AMK_ProtocolImplementation
3396 : isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration
3399 mergeDeclAttributes(newMethod, oldMethod, MergeKind);
3401 // Merge attributes from the parameters.
3402 ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(),
3403 oe = oldMethod->param_end();
3404 for (ObjCMethodDecl::param_iterator
3405 ni = newMethod->param_begin(), ne = newMethod->param_end();
3406 ni != ne && oi != oe; ++ni, ++oi)
3407 mergeParamDeclAttributes(*ni, *oi, *this);
3409 CheckObjCMethodOverride(newMethod, oldMethod);
3412 static void diagnoseVarDeclTypeMismatch(Sema &S, VarDecl *New, VarDecl* Old) {
3413 assert(!S.Context.hasSameType(New->getType(), Old->getType()));
3415 S.Diag(New->getLocation(), New->isThisDeclarationADefinition()
3416 ? diag::err_redefinition_different_type
3417 : diag::err_redeclaration_different_type)
3418 << New->getDeclName() << New->getType() << Old->getType();
3420 diag::kind PrevDiag;
3421 SourceLocation OldLocation;
3422 std::tie(PrevDiag, OldLocation)
3423 = getNoteDiagForInvalidRedeclaration(Old, New);
3424 S.Diag(OldLocation, PrevDiag);
3425 New->setInvalidDecl();
3428 /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and
3429 /// scope as a previous declaration 'Old'. Figure out how to merge their types,
3430 /// emitting diagnostics as appropriate.
3432 /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back
3433 /// to here in AddInitializerToDecl. We can't check them before the initializer
3435 void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old,
3436 bool MergeTypeWithOld) {
3437 if (New->isInvalidDecl() || Old->isInvalidDecl())
3441 if (getLangOpts().CPlusPlus) {
3442 if (New->getType()->isUndeducedType()) {
3443 // We don't know what the new type is until the initializer is attached.
3445 } else if (Context.hasSameType(New->getType(), Old->getType())) {
3446 // These could still be something that needs exception specs checked.
3447 return MergeVarDeclExceptionSpecs(New, Old);
3449 // C++ [basic.link]p10:
3450 // [...] the types specified by all declarations referring to a given
3451 // object or function shall be identical, except that declarations for an
3452 // array object can specify array types that differ by the presence or
3453 // absence of a major array bound (8.3.4).
3454 else if (Old->getType()->isArrayType() && New->getType()->isArrayType()) {
3455 const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
3456 const ArrayType *NewArray = Context.getAsArrayType(New->getType());
3458 // We are merging a variable declaration New into Old. If it has an array
3459 // bound, and that bound differs from Old's bound, we should diagnose the
3461 if (!NewArray->isIncompleteArrayType() && !NewArray->isDependentType()) {
3462 for (VarDecl *PrevVD = Old->getMostRecentDecl(); PrevVD;
3463 PrevVD = PrevVD->getPreviousDecl()) {
3464 const ArrayType *PrevVDTy = Context.getAsArrayType(PrevVD->getType());
3465 if (PrevVDTy->isIncompleteArrayType() || PrevVDTy->isDependentType())
3468 if (!Context.hasSameType(NewArray, PrevVDTy))
3469 return diagnoseVarDeclTypeMismatch(*this, New, PrevVD);
3473 if (OldArray->isIncompleteArrayType() && NewArray->isArrayType()) {
3474 if (Context.hasSameType(OldArray->getElementType(),
3475 NewArray->getElementType()))
3476 MergedT = New->getType();
3478 // FIXME: Check visibility. New is hidden but has a complete type. If New
3479 // has no array bound, it should not inherit one from Old, if Old is not
3481 else if (OldArray->isArrayType() && NewArray->isIncompleteArrayType()) {
3482 if (Context.hasSameType(OldArray->getElementType(),
3483 NewArray->getElementType()))
3484 MergedT = Old->getType();
3487 else if (New->getType()->isObjCObjectPointerType() &&
3488 Old->getType()->isObjCObjectPointerType()) {
3489 MergedT = Context.mergeObjCGCQualifiers(New->getType(),
3494 // All declarations that refer to the same object or function shall have
3496 MergedT = Context.mergeTypes(New->getType(), Old->getType());
3498 if (MergedT.isNull()) {
3499 // It's OK if we couldn't merge types if either type is dependent, for a
3500 // block-scope variable. In other cases (static data members of class
3501 // templates, variable templates, ...), we require the types to be
3503 // FIXME: The C++ standard doesn't say anything about this.
3504 if ((New->getType()->isDependentType() ||
3505 Old->getType()->isDependentType()) && New->isLocalVarDecl()) {
3506 // If the old type was dependent, we can't merge with it, so the new type
3507 // becomes dependent for now. We'll reproduce the original type when we
3508 // instantiate the TypeSourceInfo for the variable.
3509 if (!New->getType()->isDependentType() && MergeTypeWithOld)
3510 New->setType(Context.DependentTy);
3513 return diagnoseVarDeclTypeMismatch(*this, New, Old);
3516 // Don't actually update the type on the new declaration if the old
3517 // declaration was an extern declaration in a different scope.
3518 if (MergeTypeWithOld)
3519 New->setType(MergedT);
3522 static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD,
3523 LookupResult &Previous) {
3525 // For an identifier with internal or external linkage declared
3526 // in a scope in which a prior declaration of that identifier is
3527 // visible, if the prior declaration specifies internal or
3528 // external linkage, the type of the identifier at the later
3529 // declaration becomes the composite type.
3531 // If the variable isn't visible, we do not merge with its type.
3532 if (Previous.isShadowed())
3535 if (S.getLangOpts().CPlusPlus) {
3536 // C++11 [dcl.array]p3:
3537 // If there is a preceding declaration of the entity in the same
3538 // scope in which the bound was specified, an omitted array bound
3539 // is taken to be the same as in that earlier declaration.
3540 return NewVD->isPreviousDeclInSameBlockScope() ||
3541 (!OldVD->getLexicalDeclContext()->isFunctionOrMethod() &&
3542 !NewVD->getLexicalDeclContext()->isFunctionOrMethod());
3544 // If the old declaration was function-local, don't merge with its
3545 // type unless we're in the same function.
3546 return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() ||
3547 OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext();
3551 /// MergeVarDecl - We just parsed a variable 'New' which has the same name
3552 /// and scope as a previous declaration 'Old'. Figure out how to resolve this
3553 /// situation, merging decls or emitting diagnostics as appropriate.
3555 /// Tentative definition rules (C99 6.9.2p2) are checked by
3556 /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative
3557 /// definitions here, since the initializer hasn't been attached.
3559 void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
3560 // If the new decl is already invalid, don't do any other checking.
3561 if (New->isInvalidDecl())
3564 if (!shouldLinkPossiblyHiddenDecl(Previous, New))
3567 VarTemplateDecl *NewTemplate = New->getDescribedVarTemplate();
3569 // Verify the old decl was also a variable or variable template.
3570 VarDecl *Old = nullptr;
3571 VarTemplateDecl *OldTemplate = nullptr;
3572 if (Previous.isSingleResult()) {
3574 OldTemplate = dyn_cast<VarTemplateDecl>(Previous.getFoundDecl());
3575 Old = OldTemplate ? OldTemplate->getTemplatedDecl() : nullptr;
3578 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3579 if (checkUsingShadowRedecl<VarTemplateDecl>(*this, Shadow, NewTemplate))
3580 return New->setInvalidDecl();
3582 Old = dyn_cast<VarDecl>(Previous.getFoundDecl());
3585 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3586 if (checkUsingShadowRedecl<VarDecl>(*this, Shadow, New))
3587 return New->setInvalidDecl();
3591 Diag(New->getLocation(), diag::err_redefinition_different_kind)
3592 << New->getDeclName();
3593 Diag(Previous.getRepresentativeDecl()->getLocation(),
3594 diag::note_previous_definition);
3595 return New->setInvalidDecl();
3598 // Ensure the template parameters are compatible.
3600 !TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
3601 OldTemplate->getTemplateParameters(),
3602 /*Complain=*/true, TPL_TemplateMatch))
3603 return New->setInvalidDecl();
3605 // C++ [class.mem]p1:
3606 // A member shall not be declared twice in the member-specification [...]
3608 // Here, we need only consider static data members.
3609 if (Old->isStaticDataMember() && !New->isOutOfLine()) {
3610 Diag(New->getLocation(), diag::err_duplicate_member)
3611 << New->getIdentifier();
3612 Diag(Old->getLocation(), diag::note_previous_declaration);
3613 New->setInvalidDecl();
3616 mergeDeclAttributes(New, Old);
3617 // Warn if an already-declared variable is made a weak_import in a subsequent
3619 if (New->hasAttr<WeakImportAttr>() &&
3620 Old->getStorageClass() == SC_None &&
3621 !Old->hasAttr<WeakImportAttr>()) {
3622 Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName();
3623 Diag(Old->getLocation(), diag::note_previous_definition);
3624 // Remove weak_import attribute on new declaration.
3625 New->dropAttr<WeakImportAttr>();
3628 if (New->hasAttr<InternalLinkageAttr>() &&
3629 !Old->hasAttr<InternalLinkageAttr>()) {
3630 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
3631 << New->getDeclName();
3632 Diag(Old->getLocation(), diag::note_previous_definition);
3633 New->dropAttr<InternalLinkageAttr>();
3637 VarDecl *MostRecent = Old->getMostRecentDecl();
3638 if (MostRecent != Old) {
3639 MergeVarDeclTypes(New, MostRecent,
3640 mergeTypeWithPrevious(*this, New, MostRecent, Previous));
3641 if (New->isInvalidDecl())
3645 MergeVarDeclTypes(New, Old, mergeTypeWithPrevious(*this, New, Old, Previous));
3646 if (New->isInvalidDecl())
3649 diag::kind PrevDiag;
3650 SourceLocation OldLocation;
3651 std::tie(PrevDiag, OldLocation) =
3652 getNoteDiagForInvalidRedeclaration(Old, New);
3654 // [dcl.stc]p8: Check if we have a non-static decl followed by a static.
3655 if (New->getStorageClass() == SC_Static &&
3656 !New->isStaticDataMember() &&
3657 Old->hasExternalFormalLinkage()) {
3658 if (getLangOpts().MicrosoftExt) {
3659 Diag(New->getLocation(), diag::ext_static_non_static)
3660 << New->getDeclName();
3661 Diag(OldLocation, PrevDiag);
3663 Diag(New->getLocation(), diag::err_static_non_static)
3664 << New->getDeclName();
3665 Diag(OldLocation, PrevDiag);
3666 return New->setInvalidDecl();
3670 // For an identifier declared with the storage-class specifier
3671 // extern in a scope in which a prior declaration of that
3672 // identifier is visible,23) if the prior declaration specifies
3673 // internal or external linkage, the linkage of the identifier at
3674 // the later declaration is the same as the linkage specified at
3675 // the prior declaration. If no prior declaration is visible, or
3676 // if the prior declaration specifies no linkage, then the
3677 // identifier has external linkage.
3678 if (New->hasExternalStorage() && Old->hasLinkage())
3680 else if (New->getCanonicalDecl()->getStorageClass() != SC_Static &&
3681 !New->isStaticDataMember() &&
3682 Old->getCanonicalDecl()->getStorageClass() == SC_Static) {
3683 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName();
3684 Diag(OldLocation, PrevDiag);
3685 return New->setInvalidDecl();
3688 // Check if extern is followed by non-extern and vice-versa.
3689 if (New->hasExternalStorage() &&
3690 !Old->hasLinkage() && Old->isLocalVarDeclOrParm()) {
3691 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName();
3692 Diag(OldLocation, PrevDiag);
3693 return New->setInvalidDecl();
3695 if (Old->hasLinkage() && New->isLocalVarDeclOrParm() &&
3696 !New->hasExternalStorage()) {
3697 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName();
3698 Diag(OldLocation, PrevDiag);
3699 return New->setInvalidDecl();
3702 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup.
3704 // FIXME: The test for external storage here seems wrong? We still
3705 // need to check for mismatches.
3706 if (!New->hasExternalStorage() && !New->isFileVarDecl() &&
3707 // Don't complain about out-of-line definitions of static members.
3708 !(Old->getLexicalDeclContext()->isRecord() &&
3709 !New->getLexicalDeclContext()->isRecord())) {
3710 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName();
3711 Diag(OldLocation, PrevDiag);
3712 return New->setInvalidDecl();
3715 if (New->isInline() && !Old->getMostRecentDecl()->isInline()) {
3716 if (VarDecl *Def = Old->getDefinition()) {
3717 // C++1z [dcl.fcn.spec]p4:
3718 // If the definition of a variable appears in a translation unit before
3719 // its first declaration as inline, the program is ill-formed.
3720 Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
3721 Diag(Def->getLocation(), diag::note_previous_definition);
3725 // If this redeclaration makes the function inline, we may need to add it to
3726 // UndefinedButUsed.
3727 if (!Old->isInline() && New->isInline() && Old->isUsed(false) &&
3728 !Old->getDefinition() && !New->isThisDeclarationADefinition())
3729 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
3732 if (New->getTLSKind() != Old->getTLSKind()) {
3733 if (!Old->getTLSKind()) {
3734 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName();
3735 Diag(OldLocation, PrevDiag);
3736 } else if (!New->getTLSKind()) {
3737 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName();
3738 Diag(OldLocation, PrevDiag);
3740 // Do not allow redeclaration to change the variable between requiring
3741 // static and dynamic initialization.
3742 // FIXME: GCC allows this, but uses the TLS keyword on the first
3743 // declaration to determine the kind. Do we need to be compatible here?
3744 Diag(New->getLocation(), diag::err_thread_thread_different_kind)
3745 << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic);
3746 Diag(OldLocation, PrevDiag);
3750 // C++ doesn't have tentative definitions, so go right ahead and check here.
3751 if (getLangOpts().CPlusPlus &&
3752 New->isThisDeclarationADefinition() == VarDecl::Definition) {
3753 if (Old->isStaticDataMember() && Old->getCanonicalDecl()->isInline() &&
3754 Old->getCanonicalDecl()->isConstexpr()) {
3755 // This definition won't be a definition any more once it's been merged.
3756 Diag(New->getLocation(),
3757 diag::warn_deprecated_redundant_constexpr_static_def);
3758 } else if (VarDecl *Def = Old->getDefinition()) {
3759 if (checkVarDeclRedefinition(Def, New))
3764 if (haveIncompatibleLanguageLinkages(Old, New)) {
3765 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3766 Diag(OldLocation, PrevDiag);
3767 New->setInvalidDecl();
3771 // Merge "used" flag.
3772 if (Old->getMostRecentDecl()->isUsed(false))
3775 // Keep a chain of previous declarations.
3776 New->setPreviousDecl(Old);
3778 NewTemplate->setPreviousDecl(OldTemplate);
3780 // Inherit access appropriately.
3781 New->setAccess(Old->getAccess());
3783 NewTemplate->setAccess(New->getAccess());
3785 if (Old->isInline())
3786 New->setImplicitlyInline();
3789 /// We've just determined that \p Old and \p New both appear to be definitions
3790 /// of the same variable. Either diagnose or fix the problem.
3791 bool Sema::checkVarDeclRedefinition(VarDecl *Old, VarDecl *New) {
3792 if (!hasVisibleDefinition(Old) &&
3793 (New->getFormalLinkage() == InternalLinkage ||
3795 New->getDescribedVarTemplate() ||
3796 New->getNumTemplateParameterLists() ||
3797 New->getDeclContext()->isDependentContext())) {
3798 // The previous definition is hidden, and multiple definitions are
3799 // permitted (in separate TUs). Demote this to a declaration.
3800 New->demoteThisDefinitionToDeclaration();
3802 // Make the canonical definition visible.
3803 if (auto *OldTD = Old->getDescribedVarTemplate())
3804 makeMergedDefinitionVisible(OldTD, New->getLocation());
3805 makeMergedDefinitionVisible(Old, New->getLocation());
3808 Diag(New->getLocation(), diag::err_redefinition) << New;
3809 Diag(Old->getLocation(), diag::note_previous_definition);
3810 New->setInvalidDecl();
3815 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3816 /// no declarator (e.g. "struct foo;") is parsed.
3818 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3819 RecordDecl *&AnonRecord) {
3820 return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg(), false,
3824 // The MS ABI changed between VS2013 and VS2015 with regard to numbers used to
3825 // disambiguate entities defined in different scopes.
3826 // While the VS2015 ABI fixes potential miscompiles, it is also breaks
3828 // We will pick our mangling number depending on which version of MSVC is being
3830 static unsigned getMSManglingNumber(const LangOptions &LO, Scope *S) {
3831 return LO.isCompatibleWithMSVC(LangOptions::MSVC2015)
3832 ? S->getMSCurManglingNumber()
3833 : S->getMSLastManglingNumber();
3836 void Sema::handleTagNumbering(const TagDecl *Tag, Scope *TagScope) {
3837 if (!Context.getLangOpts().CPlusPlus)
3840 if (isa<CXXRecordDecl>(Tag->getParent())) {
3841 // If this tag is the direct child of a class, number it if
3843 if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl())
3845 MangleNumberingContext &MCtx =
3846 Context.getManglingNumberContext(Tag->getParent());
3847 Context.setManglingNumber(
3848 Tag, MCtx.getManglingNumber(
3849 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3853 // If this tag isn't a direct child of a class, number it if it is local.
3854 Decl *ManglingContextDecl;
3855 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
3856 Tag->getDeclContext(), ManglingContextDecl)) {
3857 Context.setManglingNumber(
3858 Tag, MCtx->getManglingNumber(
3859 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3863 void Sema::setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,
3864 TypedefNameDecl *NewTD) {
3865 if (TagFromDeclSpec->isInvalidDecl())
3868 // Do nothing if the tag already has a name for linkage purposes.
3869 if (TagFromDeclSpec->hasNameForLinkage())
3872 // A well-formed anonymous tag must always be a TUK_Definition.
3873 assert(TagFromDeclSpec->isThisDeclarationADefinition());
3875 // The type must match the tag exactly; no qualifiers allowed.
3876 if (!Context.hasSameType(NewTD->getUnderlyingType(),
3877 Context.getTagDeclType(TagFromDeclSpec))) {
3878 if (getLangOpts().CPlusPlus)
3879 Context.addTypedefNameForUnnamedTagDecl(TagFromDeclSpec, NewTD);
3883 // If we've already computed linkage for the anonymous tag, then
3884 // adding a typedef name for the anonymous decl can change that
3885 // linkage, which might be a serious problem. Diagnose this as
3886 // unsupported and ignore the typedef name. TODO: we should
3887 // pursue this as a language defect and establish a formal rule
3888 // for how to handle it.
3889 if (TagFromDeclSpec->hasLinkageBeenComputed()) {
3890 Diag(NewTD->getLocation(), diag::err_typedef_changes_linkage);
3892 SourceLocation tagLoc = TagFromDeclSpec->getInnerLocStart();
3893 tagLoc = getLocForEndOfToken(tagLoc);
3895 llvm::SmallString<40> textToInsert;
3896 textToInsert += ' ';
3897 textToInsert += NewTD->getIdentifier()->getName();
3898 Diag(tagLoc, diag::note_typedef_changes_linkage)
3899 << FixItHint::CreateInsertion(tagLoc, textToInsert);
3903 // Otherwise, set this is the anon-decl typedef for the tag.
3904 TagFromDeclSpec->setTypedefNameForAnonDecl(NewTD);
3907 static unsigned GetDiagnosticTypeSpecifierID(DeclSpec::TST T) {
3909 case DeclSpec::TST_class:
3911 case DeclSpec::TST_struct:
3913 case DeclSpec::TST_interface:
3915 case DeclSpec::TST_union:
3917 case DeclSpec::TST_enum:
3920 llvm_unreachable("unexpected type specifier");
3924 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3925 /// no declarator (e.g. "struct foo;") is parsed. It also accepts template
3926 /// parameters to cope with template friend declarations.
3928 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3929 MultiTemplateParamsArg TemplateParams,
3930 bool IsExplicitInstantiation,
3931 RecordDecl *&AnonRecord) {
3932 Decl *TagD = nullptr;
3933 TagDecl *Tag = nullptr;
3934 if (DS.getTypeSpecType() == DeclSpec::TST_class ||
3935 DS.getTypeSpecType() == DeclSpec::TST_struct ||
3936 DS.getTypeSpecType() == DeclSpec::TST_interface ||
3937 DS.getTypeSpecType() == DeclSpec::TST_union ||
3938 DS.getTypeSpecType() == DeclSpec::TST_enum) {
3939 TagD = DS.getRepAsDecl();
3941 if (!TagD) // We probably had an error
3944 // Note that the above type specs guarantee that the
3945 // type rep is a Decl, whereas in many of the others
3947 if (isa<TagDecl>(TagD))
3948 Tag = cast<TagDecl>(TagD);
3949 else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD))
3950 Tag = CTD->getTemplatedDecl();
3954 handleTagNumbering(Tag, S);
3955 Tag->setFreeStanding();
3956 if (Tag->isInvalidDecl())
3960 if (unsigned TypeQuals = DS.getTypeQualifiers()) {
3961 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object
3962 // or incomplete types shall not be restrict-qualified."
3963 if (TypeQuals & DeclSpec::TQ_restrict)
3964 Diag(DS.getRestrictSpecLoc(),
3965 diag::err_typecheck_invalid_restrict_not_pointer_noarg)
3966 << DS.getSourceRange();
3969 if (DS.isInlineSpecified())
3970 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
3971 << getLangOpts().CPlusPlus1z;
3973 if (DS.isConstexprSpecified()) {
3974 // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations
3975 // and definitions of functions and variables.
3977 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag)
3978 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType());
3980 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_no_declarators);
3981 // Don't emit warnings after this error.
3985 if (DS.isConceptSpecified()) {
3986 // C++ Concepts TS [dcl.spec.concept]p1: A concept definition refers to
3987 // either a function concept and its definition or a variable concept and
3989 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
3993 DiagnoseFunctionSpecifiers(DS);
3995 if (DS.isFriendSpecified()) {
3996 // If we're dealing with a decl but not a TagDecl, assume that
3997 // whatever routines created it handled the friendship aspect.
4000 return ActOnFriendTypeDecl(S, DS, TemplateParams);
4003 const CXXScopeSpec &SS = DS.getTypeSpecScope();
4004 bool IsExplicitSpecialization =
4005 !TemplateParams.empty() && TemplateParams.back()->size() == 0;
4006 if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() &&
4007 !IsExplicitInstantiation && !IsExplicitSpecialization &&
4008 !isa<ClassTemplatePartialSpecializationDecl>(Tag)) {
4009 // Per C++ [dcl.type.elab]p1, a class declaration cannot have a
4010 // nested-name-specifier unless it is an explicit instantiation
4011 // or an explicit specialization.
4013 // FIXME: We allow class template partial specializations here too, per the
4014 // obvious intent of DR1819.
4016 // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either.
4017 Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier)
4018 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) << SS.getRange();
4022 // Track whether this decl-specifier declares anything.
4023 bool DeclaresAnything = true;
4025 // Handle anonymous struct definitions.
4026 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
4027 if (!Record->getDeclName() && Record->isCompleteDefinition() &&
4028 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) {
4029 if (getLangOpts().CPlusPlus ||
4030 Record->getDeclContext()->isRecord()) {
4031 // If CurContext is a DeclContext that can contain statements,
4032 // RecursiveASTVisitor won't visit the decls that
4033 // BuildAnonymousStructOrUnion() will put into CurContext.
4034 // Also store them here so that they can be part of the
4035 // DeclStmt that gets created in this case.
4036 // FIXME: Also return the IndirectFieldDecls created by
4037 // BuildAnonymousStructOr union, for the same reason?
4038 if (CurContext->isFunctionOrMethod())
4039 AnonRecord = Record;
4040 return BuildAnonymousStructOrUnion(S, DS, AS, Record,
4041 Context.getPrintingPolicy());
4044 DeclaresAnything = false;
4049 // A struct-declaration that does not declare an anonymous structure or
4050 // anonymous union shall contain a struct-declarator-list.
4052 // This rule also existed in C89 and C99; the grammar for struct-declaration
4053 // did not permit a struct-declaration without a struct-declarator-list.
4054 if (!getLangOpts().CPlusPlus && CurContext->isRecord() &&
4055 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) {
4056 // Check for Microsoft C extension: anonymous struct/union member.
4057 // Handle 2 kinds of anonymous struct/union:
4061 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct.
4062 // UNION_TYPE; <- where UNION_TYPE is a typedef union.
4063 if ((Tag && Tag->getDeclName()) ||
4064 DS.getTypeSpecType() == DeclSpec::TST_typename) {
4065 RecordDecl *Record = nullptr;
4067 Record = dyn_cast<RecordDecl>(Tag);
4068 else if (const RecordType *RT =
4069 DS.getRepAsType().get()->getAsStructureType())
4070 Record = RT->getDecl();
4071 else if (const RecordType *UT = DS.getRepAsType().get()->getAsUnionType())
4072 Record = UT->getDecl();
4074 if (Record && getLangOpts().MicrosoftExt) {
4075 Diag(DS.getLocStart(), diag::ext_ms_anonymous_record)
4076 << Record->isUnion() << DS.getSourceRange();
4077 return BuildMicrosoftCAnonymousStruct(S, DS, Record);
4080 DeclaresAnything = false;
4084 // Skip all the checks below if we have a type error.
4085 if (DS.getTypeSpecType() == DeclSpec::TST_error ||
4086 (TagD && TagD->isInvalidDecl()))
4089 if (getLangOpts().CPlusPlus &&
4090 DS.getStorageClassSpec() != DeclSpec::SCS_typedef)
4091 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag))
4092 if (Enum->enumerator_begin() == Enum->enumerator_end() &&
4093 !Enum->getIdentifier() && !Enum->isInvalidDecl())
4094 DeclaresAnything = false;
4096 if (!DS.isMissingDeclaratorOk()) {
4097 // Customize diagnostic for a typedef missing a name.
4098 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
4099 Diag(DS.getLocStart(), diag::ext_typedef_without_a_name)
4100 << DS.getSourceRange();
4102 DeclaresAnything = false;
4105 if (DS.isModulePrivateSpecified() &&
4106 Tag && Tag->getDeclContext()->isFunctionOrMethod())
4107 Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class)
4108 << Tag->getTagKind()
4109 << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc());
4111 ActOnDocumentableDecl(TagD);
4114 // A declaration [...] shall declare at least a declarator [...], a tag,
4115 // or the members of an enumeration.
4117 // [If there are no declarators], and except for the declaration of an
4118 // unnamed bit-field, the decl-specifier-seq shall introduce one or more
4119 // names into the program, or shall redeclare a name introduced by a
4120 // previous declaration.
4121 if (!DeclaresAnything) {
4122 // In C, we allow this as a (popular) extension / bug. Don't bother
4123 // producing further diagnostics for redundant qualifiers after this.
4124 Diag(DS.getLocStart(), diag::ext_no_declarators) << DS.getSourceRange();
4129 // If a storage-class-specifier appears in a decl-specifier-seq, [...] the
4130 // init-declarator-list of the declaration shall not be empty.
4131 // C++ [dcl.fct.spec]p1:
4132 // If a cv-qualifier appears in a decl-specifier-seq, the
4133 // init-declarator-list of the declaration shall not be empty.
4135 // Spurious qualifiers here appear to be valid in C.
4136 unsigned DiagID = diag::warn_standalone_specifier;
4137 if (getLangOpts().CPlusPlus)
4138 DiagID = diag::ext_standalone_specifier;
4140 // Note that a linkage-specification sets a storage class, but
4141 // 'extern "C" struct foo;' is actually valid and not theoretically
4143 if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
4144 if (SCS == DeclSpec::SCS_mutable)
4145 // Since mutable is not a viable storage class specifier in C, there is
4146 // no reason to treat it as an extension. Instead, diagnose as an error.
4147 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_nonmember);
4148 else if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef)
4149 Diag(DS.getStorageClassSpecLoc(), DiagID)
4150 << DeclSpec::getSpecifierName(SCS);
4153 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
4154 Diag(DS.getThreadStorageClassSpecLoc(), DiagID)
4155 << DeclSpec::getSpecifierName(TSCS);
4156 if (DS.getTypeQualifiers()) {
4157 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4158 Diag(DS.getConstSpecLoc(), DiagID) << "const";
4159 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4160 Diag(DS.getConstSpecLoc(), DiagID) << "volatile";
4161 // Restrict is covered above.
4162 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4163 Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic";
4164 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4165 Diag(DS.getUnalignedSpecLoc(), DiagID) << "__unaligned";
4168 // Warn about ignored type attributes, for example:
4169 // __attribute__((aligned)) struct A;
4170 // Attributes should be placed after tag to apply to type declaration.
4171 if (!DS.getAttributes().empty()) {
4172 DeclSpec::TST TypeSpecType = DS.getTypeSpecType();
4173 if (TypeSpecType == DeclSpec::TST_class ||
4174 TypeSpecType == DeclSpec::TST_struct ||
4175 TypeSpecType == DeclSpec::TST_interface ||
4176 TypeSpecType == DeclSpec::TST_union ||
4177 TypeSpecType == DeclSpec::TST_enum) {
4178 for (AttributeList* attrs = DS.getAttributes().getList(); attrs;
4179 attrs = attrs->getNext())
4180 Diag(attrs->getLoc(), diag::warn_declspec_attribute_ignored)
4181 << attrs->getName() << GetDiagnosticTypeSpecifierID(TypeSpecType);
4188 /// We are trying to inject an anonymous member into the given scope;
4189 /// check if there's an existing declaration that can't be overloaded.
4191 /// \return true if this is a forbidden redeclaration
4192 static bool CheckAnonMemberRedeclaration(Sema &SemaRef,
4195 DeclarationName Name,
4196 SourceLocation NameLoc,
4198 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName,
4199 Sema::ForRedeclaration);
4200 if (!SemaRef.LookupName(R, S)) return false;
4202 // Pick a representative declaration.
4203 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl();
4204 assert(PrevDecl && "Expected a non-null Decl");
4206 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S))
4209 SemaRef.Diag(NameLoc, diag::err_anonymous_record_member_redecl)
4211 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
4216 /// InjectAnonymousStructOrUnionMembers - Inject the members of the
4217 /// anonymous struct or union AnonRecord into the owning context Owner
4218 /// and scope S. This routine will be invoked just after we realize
4219 /// that an unnamed union or struct is actually an anonymous union or
4226 /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and
4227 /// // f into the surrounding scope.x
4230 /// This routine is recursive, injecting the names of nested anonymous
4231 /// structs/unions into the owning context and scope as well.
4233 InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, DeclContext *Owner,
4234 RecordDecl *AnonRecord, AccessSpecifier AS,
4235 SmallVectorImpl<NamedDecl *> &Chaining) {
4236 bool Invalid = false;
4238 // Look every FieldDecl and IndirectFieldDecl with a name.
4239 for (auto *D : AnonRecord->decls()) {
4240 if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) &&
4241 cast<NamedDecl>(D)->getDeclName()) {
4242 ValueDecl *VD = cast<ValueDecl>(D);
4243 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(),
4245 AnonRecord->isUnion())) {
4246 // C++ [class.union]p2:
4247 // The names of the members of an anonymous union shall be
4248 // distinct from the names of any other entity in the
4249 // scope in which the anonymous union is declared.
4252 // C++ [class.union]p2:
4253 // For the purpose of name lookup, after the anonymous union
4254 // definition, the members of the anonymous union are
4255 // considered to have been defined in the scope in which the
4256 // anonymous union is declared.
4257 unsigned OldChainingSize = Chaining.size();
4258 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD))
4259 Chaining.append(IF->chain_begin(), IF->chain_end());
4261 Chaining.push_back(VD);
4263 assert(Chaining.size() >= 2);
4264 NamedDecl **NamedChain =
4265 new (SemaRef.Context)NamedDecl*[Chaining.size()];
4266 for (unsigned i = 0; i < Chaining.size(); i++)
4267 NamedChain[i] = Chaining[i];
4269 IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
4270 SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(),
4271 VD->getType(), {NamedChain, Chaining.size()});
4273 for (const auto *Attr : VD->attrs())
4274 IndirectField->addAttr(Attr->clone(SemaRef.Context));
4276 IndirectField->setAccess(AS);
4277 IndirectField->setImplicit();
4278 SemaRef.PushOnScopeChains(IndirectField, S);
4280 // That includes picking up the appropriate access specifier.
4281 if (AS != AS_none) IndirectField->setAccess(AS);
4283 Chaining.resize(OldChainingSize);
4291 /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to
4292 /// a VarDecl::StorageClass. Any error reporting is up to the caller:
4293 /// illegal input values are mapped to SC_None.
4295 StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) {
4296 DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec();
4297 assert(StorageClassSpec != DeclSpec::SCS_typedef &&
4298 "Parser allowed 'typedef' as storage class VarDecl.");
4299 switch (StorageClassSpec) {
4300 case DeclSpec::SCS_unspecified: return SC_None;
4301 case DeclSpec::SCS_extern:
4302 if (DS.isExternInLinkageSpec())
4305 case DeclSpec::SCS_static: return SC_Static;
4306 case DeclSpec::SCS_auto: return SC_Auto;
4307 case DeclSpec::SCS_register: return SC_Register;
4308 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
4309 // Illegal SCSs map to None: error reporting is up to the caller.
4310 case DeclSpec::SCS_mutable: // Fall through.
4311 case DeclSpec::SCS_typedef: return SC_None;
4313 llvm_unreachable("unknown storage class specifier");
4316 static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) {
4317 assert(Record->hasInClassInitializer());
4319 for (const auto *I : Record->decls()) {
4320 const auto *FD = dyn_cast<FieldDecl>(I);
4321 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
4322 FD = IFD->getAnonField();
4323 if (FD && FD->hasInClassInitializer())
4324 return FD->getLocation();
4327 llvm_unreachable("couldn't find in-class initializer");
4330 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4331 SourceLocation DefaultInitLoc) {
4332 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4335 S.Diag(DefaultInitLoc, diag::err_multiple_mem_union_initialization);
4336 S.Diag(findDefaultInitializer(Parent), diag::note_previous_initializer) << 0;
4339 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4340 CXXRecordDecl *AnonUnion) {
4341 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4344 checkDuplicateDefaultInit(S, Parent, findDefaultInitializer(AnonUnion));
4347 /// BuildAnonymousStructOrUnion - Handle the declaration of an
4348 /// anonymous structure or union. Anonymous unions are a C++ feature
4349 /// (C++ [class.union]) and a C11 feature; anonymous structures
4350 /// are a C11 feature and GNU C++ extension.
4351 Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
4354 const PrintingPolicy &Policy) {
4355 DeclContext *Owner = Record->getDeclContext();
4357 // Diagnose whether this anonymous struct/union is an extension.
4358 if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11)
4359 Diag(Record->getLocation(), diag::ext_anonymous_union);
4360 else if (!Record->isUnion() && getLangOpts().CPlusPlus)
4361 Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct);
4362 else if (!Record->isUnion() && !getLangOpts().C11)
4363 Diag(Record->getLocation(), diag::ext_c11_anonymous_struct);
4365 // C and C++ require different kinds of checks for anonymous
4367 bool Invalid = false;
4368 if (getLangOpts().CPlusPlus) {
4369 const char *PrevSpec = nullptr;
4371 if (Record->isUnion()) {
4372 // C++ [class.union]p6:
4373 // Anonymous unions declared in a named namespace or in the
4374 // global namespace shall be declared static.
4375 if (DS.getStorageClassSpec() != DeclSpec::SCS_static &&
4376 (isa<TranslationUnitDecl>(Owner) ||
4377 (isa<NamespaceDecl>(Owner) &&
4378 cast<NamespaceDecl>(Owner)->getDeclName()))) {
4379 Diag(Record->getLocation(), diag::err_anonymous_union_not_static)
4380 << FixItHint::CreateInsertion(Record->getLocation(), "static ");
4382 // Recover by adding 'static'.
4383 DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(),
4384 PrevSpec, DiagID, Policy);
4386 // C++ [class.union]p6:
4387 // A storage class is not allowed in a declaration of an
4388 // anonymous union in a class scope.
4389 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
4390 isa<RecordDecl>(Owner)) {
4391 Diag(DS.getStorageClassSpecLoc(),
4392 diag::err_anonymous_union_with_storage_spec)
4393 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
4395 // Recover by removing the storage specifier.
4396 DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified,
4398 PrevSpec, DiagID, Context.getPrintingPolicy());
4402 // Ignore const/volatile/restrict qualifiers.
4403 if (DS.getTypeQualifiers()) {
4404 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4405 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified)
4406 << Record->isUnion() << "const"
4407 << FixItHint::CreateRemoval(DS.getConstSpecLoc());
4408 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4409 Diag(DS.getVolatileSpecLoc(),
4410 diag::ext_anonymous_struct_union_qualified)
4411 << Record->isUnion() << "volatile"
4412 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc());
4413 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
4414 Diag(DS.getRestrictSpecLoc(),
4415 diag::ext_anonymous_struct_union_qualified)
4416 << Record->isUnion() << "restrict"
4417 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc());
4418 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4419 Diag(DS.getAtomicSpecLoc(),
4420 diag::ext_anonymous_struct_union_qualified)
4421 << Record->isUnion() << "_Atomic"
4422 << FixItHint::CreateRemoval(DS.getAtomicSpecLoc());
4423 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4424 Diag(DS.getUnalignedSpecLoc(),
4425 diag::ext_anonymous_struct_union_qualified)
4426 << Record->isUnion() << "__unaligned"
4427 << FixItHint::CreateRemoval(DS.getUnalignedSpecLoc());
4429 DS.ClearTypeQualifiers();
4432 // C++ [class.union]p2:
4433 // The member-specification of an anonymous union shall only
4434 // define non-static data members. [Note: nested types and
4435 // functions cannot be declared within an anonymous union. ]
4436 for (auto *Mem : Record->decls()) {
4437 if (auto *FD = dyn_cast<FieldDecl>(Mem)) {
4438 // C++ [class.union]p3:
4439 // An anonymous union shall not have private or protected
4440 // members (clause 11).
4441 assert(FD->getAccess() != AS_none);
4442 if (FD->getAccess() != AS_public) {
4443 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member)
4444 << Record->isUnion() << (FD->getAccess() == AS_protected);
4448 // C++ [class.union]p1
4449 // An object of a class with a non-trivial constructor, a non-trivial
4450 // copy constructor, a non-trivial destructor, or a non-trivial copy
4451 // assignment operator cannot be a member of a union, nor can an
4452 // array of such objects.
4453 if (CheckNontrivialField(FD))
4455 } else if (Mem->isImplicit()) {
4456 // Any implicit members are fine.
4457 } else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) {
4458 // This is a type that showed up in an
4459 // elaborated-type-specifier inside the anonymous struct or
4460 // union, but which actually declares a type outside of the
4461 // anonymous struct or union. It's okay.
4462 } else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) {
4463 if (!MemRecord->isAnonymousStructOrUnion() &&
4464 MemRecord->getDeclName()) {
4465 // Visual C++ allows type definition in anonymous struct or union.
4466 if (getLangOpts().MicrosoftExt)
4467 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type)
4468 << Record->isUnion();
4470 // This is a nested type declaration.
4471 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type)
4472 << Record->isUnion();
4476 // This is an anonymous type definition within another anonymous type.
4477 // This is a popular extension, provided by Plan9, MSVC and GCC, but
4478 // not part of standard C++.
4479 Diag(MemRecord->getLocation(),
4480 diag::ext_anonymous_record_with_anonymous_type)
4481 << Record->isUnion();
4483 } else if (isa<AccessSpecDecl>(Mem)) {
4484 // Any access specifier is fine.
4485 } else if (isa<StaticAssertDecl>(Mem)) {
4486 // In C++1z, static_assert declarations are also fine.
4488 // We have something that isn't a non-static data
4489 // member. Complain about it.
4490 unsigned DK = diag::err_anonymous_record_bad_member;
4491 if (isa<TypeDecl>(Mem))
4492 DK = diag::err_anonymous_record_with_type;
4493 else if (isa<FunctionDecl>(Mem))
4494 DK = diag::err_anonymous_record_with_function;
4495 else if (isa<VarDecl>(Mem))
4496 DK = diag::err_anonymous_record_with_static;
4498 // Visual C++ allows type definition in anonymous struct or union.
4499 if (getLangOpts().MicrosoftExt &&
4500 DK == diag::err_anonymous_record_with_type)
4501 Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type)
4502 << Record->isUnion();
4504 Diag(Mem->getLocation(), DK) << Record->isUnion();
4510 // C++11 [class.union]p8 (DR1460):
4511 // At most one variant member of a union may have a
4512 // brace-or-equal-initializer.
4513 if (cast<CXXRecordDecl>(Record)->hasInClassInitializer() &&
4515 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Owner),
4516 cast<CXXRecordDecl>(Record));
4519 if (!Record->isUnion() && !Owner->isRecord()) {
4520 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member)
4521 << getLangOpts().CPlusPlus;
4525 // Mock up a declarator.
4526 Declarator Dc(DS, Declarator::MemberContext);
4527 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4528 assert(TInfo && "couldn't build declarator info for anonymous struct/union");
4530 // Create a declaration for this anonymous struct/union.
4531 NamedDecl *Anon = nullptr;
4532 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) {
4533 Anon = FieldDecl::Create(Context, OwningClass,
4535 Record->getLocation(),
4536 /*IdentifierInfo=*/nullptr,
4537 Context.getTypeDeclType(Record),
4539 /*BitWidth=*/nullptr, /*Mutable=*/false,
4540 /*InitStyle=*/ICIS_NoInit);
4541 Anon->setAccess(AS);
4542 if (getLangOpts().CPlusPlus)
4543 FieldCollector->Add(cast<FieldDecl>(Anon));
4545 DeclSpec::SCS SCSpec = DS.getStorageClassSpec();
4546 StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS);
4547 if (SCSpec == DeclSpec::SCS_mutable) {
4548 // mutable can only appear on non-static class members, so it's always
4550 Diag(Record->getLocation(), diag::err_mutable_nonmember);
4555 Anon = VarDecl::Create(Context, Owner,
4557 Record->getLocation(), /*IdentifierInfo=*/nullptr,
4558 Context.getTypeDeclType(Record),
4561 // Default-initialize the implicit variable. This initialization will be
4562 // trivial in almost all cases, except if a union member has an in-class
4564 // union { int n = 0; };
4565 ActOnUninitializedDecl(Anon);
4567 Anon->setImplicit();
4569 // Mark this as an anonymous struct/union type.
4570 Record->setAnonymousStructOrUnion(true);
4572 // Add the anonymous struct/union object to the current
4573 // context. We'll be referencing this object when we refer to one of
4575 Owner->addDecl(Anon);
4577 // Inject the members of the anonymous struct/union into the owning
4578 // context and into the identifier resolver chain for name lookup
4580 SmallVector<NamedDecl*, 2> Chain;
4581 Chain.push_back(Anon);
4583 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, Chain))
4586 if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) {
4587 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
4588 Decl *ManglingContextDecl;
4589 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
4590 NewVD->getDeclContext(), ManglingContextDecl)) {
4591 Context.setManglingNumber(
4592 NewVD, MCtx->getManglingNumber(
4593 NewVD, getMSManglingNumber(getLangOpts(), S)));
4594 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
4600 Anon->setInvalidDecl();
4605 /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an
4606 /// Microsoft C anonymous structure.
4607 /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx
4610 /// struct A { int a; };
4611 /// struct B { struct A; int b; };
4618 Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
4619 RecordDecl *Record) {
4620 assert(Record && "expected a record!");
4622 // Mock up a declarator.
4623 Declarator Dc(DS, Declarator::TypeNameContext);
4624 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4625 assert(TInfo && "couldn't build declarator info for anonymous struct");
4627 auto *ParentDecl = cast<RecordDecl>(CurContext);
4628 QualType RecTy = Context.getTypeDeclType(Record);
4630 // Create a declaration for this anonymous struct.
4631 NamedDecl *Anon = FieldDecl::Create(Context,
4635 /*IdentifierInfo=*/nullptr,
4638 /*BitWidth=*/nullptr, /*Mutable=*/false,
4639 /*InitStyle=*/ICIS_NoInit);
4640 Anon->setImplicit();
4642 // Add the anonymous struct object to the current context.
4643 CurContext->addDecl(Anon);
4645 // Inject the members of the anonymous struct into the current
4646 // context and into the identifier resolver chain for name lookup
4648 SmallVector<NamedDecl*, 2> Chain;
4649 Chain.push_back(Anon);
4651 RecordDecl *RecordDef = Record->getDefinition();
4652 if (RequireCompleteType(Anon->getLocation(), RecTy,
4653 diag::err_field_incomplete) ||
4654 InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef,
4656 Anon->setInvalidDecl();
4657 ParentDecl->setInvalidDecl();
4663 /// GetNameForDeclarator - Determine the full declaration name for the
4664 /// given Declarator.
4665 DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) {
4666 return GetNameFromUnqualifiedId(D.getName());
4669 /// \brief Retrieves the declaration name from a parsed unqualified-id.
4671 Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
4672 DeclarationNameInfo NameInfo;
4673 NameInfo.setLoc(Name.StartLocation);
4675 switch (Name.getKind()) {
4677 case UnqualifiedId::IK_ImplicitSelfParam:
4678 case UnqualifiedId::IK_Identifier:
4679 NameInfo.setName(Name.Identifier);
4680 NameInfo.setLoc(Name.StartLocation);
4683 case UnqualifiedId::IK_DeductionGuideName: {
4684 // C++ [temp.deduct.guide]p3:
4685 // The simple-template-id shall name a class template specialization.
4686 // The template-name shall be the same identifier as the template-name
4687 // of the simple-template-id.
4688 // These together intend to imply that the template-name shall name a
4690 // FIXME: template<typename T> struct X {};
4691 // template<typename T> using Y = X<T>;
4692 // Y(int) -> Y<int>;
4693 // satisfies these rules but does not name a class template.
4694 TemplateName TN = Name.TemplateName.get().get();
4695 auto *Template = TN.getAsTemplateDecl();
4696 if (!Template || !isa<ClassTemplateDecl>(Template)) {
4697 Diag(Name.StartLocation,
4698 diag::err_deduction_guide_name_not_class_template)
4699 << (int)getTemplateNameKindForDiagnostics(TN) << TN;
4701 Diag(Template->getLocation(), diag::note_template_decl_here);
4702 return DeclarationNameInfo();
4706 Context.DeclarationNames.getCXXDeductionGuideName(Template));
4707 NameInfo.setLoc(Name.StartLocation);
4711 case UnqualifiedId::IK_OperatorFunctionId:
4712 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName(
4713 Name.OperatorFunctionId.Operator));
4714 NameInfo.setLoc(Name.StartLocation);
4715 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc
4716 = Name.OperatorFunctionId.SymbolLocations[0];
4717 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc
4718 = Name.EndLocation.getRawEncoding();
4721 case UnqualifiedId::IK_LiteralOperatorId:
4722 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName(
4724 NameInfo.setLoc(Name.StartLocation);
4725 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation);
4728 case UnqualifiedId::IK_ConversionFunctionId: {
4729 TypeSourceInfo *TInfo;
4730 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo);
4732 return DeclarationNameInfo();
4733 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName(
4734 Context.getCanonicalType(Ty)));
4735 NameInfo.setLoc(Name.StartLocation);
4736 NameInfo.setNamedTypeInfo(TInfo);
4740 case UnqualifiedId::IK_ConstructorName: {
4741 TypeSourceInfo *TInfo;
4742 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo);
4744 return DeclarationNameInfo();
4745 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4746 Context.getCanonicalType(Ty)));
4747 NameInfo.setLoc(Name.StartLocation);
4748 NameInfo.setNamedTypeInfo(TInfo);
4752 case UnqualifiedId::IK_ConstructorTemplateId: {
4753 // In well-formed code, we can only have a constructor
4754 // template-id that refers to the current context, so go there
4755 // to find the actual type being constructed.
4756 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext);
4757 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name)
4758 return DeclarationNameInfo();
4760 // Determine the type of the class being constructed.
4761 QualType CurClassType = Context.getTypeDeclType(CurClass);
4763 // FIXME: Check two things: that the template-id names the same type as
4764 // CurClassType, and that the template-id does not occur when the name
4767 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4768 Context.getCanonicalType(CurClassType)));
4769 NameInfo.setLoc(Name.StartLocation);
4770 // FIXME: should we retrieve TypeSourceInfo?
4771 NameInfo.setNamedTypeInfo(nullptr);
4775 case UnqualifiedId::IK_DestructorName: {
4776 TypeSourceInfo *TInfo;
4777 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo);
4779 return DeclarationNameInfo();
4780 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName(
4781 Context.getCanonicalType(Ty)));
4782 NameInfo.setLoc(Name.StartLocation);
4783 NameInfo.setNamedTypeInfo(TInfo);
4787 case UnqualifiedId::IK_TemplateId: {
4788 TemplateName TName = Name.TemplateId->Template.get();
4789 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc;
4790 return Context.getNameForTemplate(TName, TNameLoc);
4793 } // switch (Name.getKind())
4795 llvm_unreachable("Unknown name kind");
4798 static QualType getCoreType(QualType Ty) {
4800 if (Ty->isPointerType() || Ty->isReferenceType())
4801 Ty = Ty->getPointeeType();
4802 else if (Ty->isArrayType())
4803 Ty = Ty->castAsArrayTypeUnsafe()->getElementType();
4805 return Ty.withoutLocalFastQualifiers();
4809 /// hasSimilarParameters - Determine whether the C++ functions Declaration
4810 /// and Definition have "nearly" matching parameters. This heuristic is
4811 /// used to improve diagnostics in the case where an out-of-line function
4812 /// definition doesn't match any declaration within the class or namespace.
4813 /// Also sets Params to the list of indices to the parameters that differ
4814 /// between the declaration and the definition. If hasSimilarParameters
4815 /// returns true and Params is empty, then all of the parameters match.
4816 static bool hasSimilarParameters(ASTContext &Context,
4817 FunctionDecl *Declaration,
4818 FunctionDecl *Definition,
4819 SmallVectorImpl<unsigned> &Params) {
4821 if (Declaration->param_size() != Definition->param_size())
4823 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) {
4824 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType();
4825 QualType DefParamTy = Definition->getParamDecl(Idx)->getType();
4827 // The parameter types are identical
4828 if (Context.hasSameType(DefParamTy, DeclParamTy))
4831 QualType DeclParamBaseTy = getCoreType(DeclParamTy);
4832 QualType DefParamBaseTy = getCoreType(DefParamTy);
4833 const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier();
4834 const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier();
4836 if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) ||
4837 (DeclTyName && DeclTyName == DefTyName))
4838 Params.push_back(Idx);
4839 else // The two parameters aren't even close
4846 /// NeedsRebuildingInCurrentInstantiation - Checks whether the given
4847 /// declarator needs to be rebuilt in the current instantiation.
4848 /// Any bits of declarator which appear before the name are valid for
4849 /// consideration here. That's specifically the type in the decl spec
4850 /// and the base type in any member-pointer chunks.
4851 static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D,
4852 DeclarationName Name) {
4853 // The types we specifically need to rebuild are:
4854 // - typenames, typeofs, and decltypes
4855 // - types which will become injected class names
4856 // Of course, we also need to rebuild any type referencing such a
4857 // type. It's safest to just say "dependent", but we call out a
4860 DeclSpec &DS = D.getMutableDeclSpec();
4861 switch (DS.getTypeSpecType()) {
4862 case DeclSpec::TST_typename:
4863 case DeclSpec::TST_typeofType:
4864 case DeclSpec::TST_underlyingType:
4865 case DeclSpec::TST_atomic: {
4866 // Grab the type from the parser.
4867 TypeSourceInfo *TSI = nullptr;
4868 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI);
4869 if (T.isNull() || !T->isDependentType()) break;
4871 // Make sure there's a type source info. This isn't really much
4872 // of a waste; most dependent types should have type source info
4873 // attached already.
4875 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc());
4877 // Rebuild the type in the current instantiation.
4878 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name);
4879 if (!TSI) return true;
4881 // Store the new type back in the decl spec.
4882 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI);
4883 DS.UpdateTypeRep(LocType);
4887 case DeclSpec::TST_decltype:
4888 case DeclSpec::TST_typeofExpr: {
4889 Expr *E = DS.getRepAsExpr();
4890 ExprResult Result = S.RebuildExprInCurrentInstantiation(E);
4891 if (Result.isInvalid()) return true;
4892 DS.UpdateExprRep(Result.get());
4897 // Nothing to do for these decl specs.
4901 // It doesn't matter what order we do this in.
4902 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
4903 DeclaratorChunk &Chunk = D.getTypeObject(I);
4905 // The only type information in the declarator which can come
4906 // before the declaration name is the base type of a member
4908 if (Chunk.Kind != DeclaratorChunk::MemberPointer)
4911 // Rebuild the scope specifier in-place.
4912 CXXScopeSpec &SS = Chunk.Mem.Scope();
4913 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS))
4920 Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) {
4921 D.setFunctionDefinitionKind(FDK_Declaration);
4922 Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg());
4924 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() &&
4925 Dcl && Dcl->getDeclContext()->isFileContext())
4926 Dcl->setTopLevelDeclInObjCContainer();
4928 if (getLangOpts().OpenCL)
4929 setCurrentOpenCLExtensionForDecl(Dcl);
4934 /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13:
4935 /// If T is the name of a class, then each of the following shall have a
4936 /// name different from T:
4937 /// - every static data member of class T;
4938 /// - every member function of class T
4939 /// - every member of class T that is itself a type;
4940 /// \returns true if the declaration name violates these rules.
4941 bool Sema::DiagnoseClassNameShadow(DeclContext *DC,
4942 DeclarationNameInfo NameInfo) {
4943 DeclarationName Name = NameInfo.getName();
4945 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC);
4946 while (Record && Record->isAnonymousStructOrUnion())
4947 Record = dyn_cast<CXXRecordDecl>(Record->getParent());
4948 if (Record && Record->getIdentifier() && Record->getDeclName() == Name) {
4949 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name;
4956 /// \brief Diagnose a declaration whose declarator-id has the given
4957 /// nested-name-specifier.
4959 /// \param SS The nested-name-specifier of the declarator-id.
4961 /// \param DC The declaration context to which the nested-name-specifier
4964 /// \param Name The name of the entity being declared.
4966 /// \param Loc The location of the name of the entity being declared.
4968 /// \returns true if we cannot safely recover from this error, false otherwise.
4969 bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
4970 DeclarationName Name,
4971 SourceLocation Loc) {
4972 DeclContext *Cur = CurContext;
4973 while (isa<LinkageSpecDecl>(Cur) || isa<CapturedDecl>(Cur))
4974 Cur = Cur->getParent();
4976 // If the user provided a superfluous scope specifier that refers back to the
4977 // class in which the entity is already declared, diagnose and ignore it.
4983 // Note, it was once ill-formed to give redundant qualification in all
4984 // contexts, but that rule was removed by DR482.
4985 if (Cur->Equals(DC)) {
4986 if (Cur->isRecord()) {
4987 Diag(Loc, LangOpts.MicrosoftExt ? diag::warn_member_extra_qualification
4988 : diag::err_member_extra_qualification)
4989 << Name << FixItHint::CreateRemoval(SS.getRange());
4992 Diag(Loc, diag::warn_namespace_member_extra_qualification) << Name;
4997 // Check whether the qualifying scope encloses the scope of the original
4999 if (!Cur->Encloses(DC)) {
5000 if (Cur->isRecord())
5001 Diag(Loc, diag::err_member_qualification)
5002 << Name << SS.getRange();
5003 else if (isa<TranslationUnitDecl>(DC))
5004 Diag(Loc, diag::err_invalid_declarator_global_scope)
5005 << Name << SS.getRange();
5006 else if (isa<FunctionDecl>(Cur))
5007 Diag(Loc, diag::err_invalid_declarator_in_function)
5008 << Name << SS.getRange();
5009 else if (isa<BlockDecl>(Cur))
5010 Diag(Loc, diag::err_invalid_declarator_in_block)
5011 << Name << SS.getRange();
5013 Diag(Loc, diag::err_invalid_declarator_scope)
5014 << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange();
5019 if (Cur->isRecord()) {
5020 // Cannot qualify members within a class.
5021 Diag(Loc, diag::err_member_qualification)
5022 << Name << SS.getRange();
5025 // C++ constructors and destructors with incorrect scopes can break
5026 // our AST invariants by having the wrong underlying types. If
5027 // that's the case, then drop this declaration entirely.
5028 if ((Name.getNameKind() == DeclarationName::CXXConstructorName ||
5029 Name.getNameKind() == DeclarationName::CXXDestructorName) &&
5030 !Context.hasSameType(Name.getCXXNameType(),
5031 Context.getTypeDeclType(cast<CXXRecordDecl>(Cur))))
5037 // C++11 [dcl.meaning]p1:
5038 // [...] "The nested-name-specifier of the qualified declarator-id shall
5039 // not begin with a decltype-specifer"
5040 NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data());
5041 while (SpecLoc.getPrefix())
5042 SpecLoc = SpecLoc.getPrefix();
5043 if (dyn_cast_or_null<DecltypeType>(
5044 SpecLoc.getNestedNameSpecifier()->getAsType()))
5045 Diag(Loc, diag::err_decltype_in_declarator)
5046 << SpecLoc.getTypeLoc().getSourceRange();
5051 NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
5052 MultiTemplateParamsArg TemplateParamLists) {
5053 // TODO: consider using NameInfo for diagnostic.
5054 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
5055 DeclarationName Name = NameInfo.getName();
5057 // All of these full declarators require an identifier. If it doesn't have
5058 // one, the ParsedFreeStandingDeclSpec action should be used.
5059 if (D.isDecompositionDeclarator()) {
5060 return ActOnDecompositionDeclarator(S, D, TemplateParamLists);
5062 if (!D.isInvalidType()) // Reject this if we think it is valid.
5063 Diag(D.getDeclSpec().getLocStart(),
5064 diag::err_declarator_need_ident)
5065 << D.getDeclSpec().getSourceRange() << D.getSourceRange();
5067 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType))
5070 // The scope passed in may not be a decl scope. Zip up the scope tree until
5071 // we find one that is.
5072 while ((S->getFlags() & Scope::DeclScope) == 0 ||
5073 (S->getFlags() & Scope::TemplateParamScope) != 0)
5076 DeclContext *DC = CurContext;
5077 if (D.getCXXScopeSpec().isInvalid())
5079 else if (D.getCXXScopeSpec().isSet()) {
5080 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(),
5081 UPPC_DeclarationQualifier))
5084 bool EnteringContext = !D.getDeclSpec().isFriendSpecified();
5085 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext);
5086 if (!DC || isa<EnumDecl>(DC)) {
5087 // If we could not compute the declaration context, it's because the
5088 // declaration context is dependent but does not refer to a class,
5089 // class template, or class template partial specialization. Complain
5090 // and return early, to avoid the coming semantic disaster.
5091 Diag(D.getIdentifierLoc(),
5092 diag::err_template_qualified_declarator_no_match)
5093 << D.getCXXScopeSpec().getScopeRep()
5094 << D.getCXXScopeSpec().getRange();
5097 bool IsDependentContext = DC->isDependentContext();
5099 if (!IsDependentContext &&
5100 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC))
5103 // If a class is incomplete, do not parse entities inside it.
5104 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) {
5105 Diag(D.getIdentifierLoc(),
5106 diag::err_member_def_undefined_record)
5107 << Name << DC << D.getCXXScopeSpec().getRange();
5110 if (!D.getDeclSpec().isFriendSpecified()) {
5111 if (diagnoseQualifiedDeclaration(D.getCXXScopeSpec(), DC,
5112 Name, D.getIdentifierLoc())) {
5120 // Check whether we need to rebuild the type of the given
5121 // declaration in the current instantiation.
5122 if (EnteringContext && IsDependentContext &&
5123 TemplateParamLists.size() != 0) {
5124 ContextRAII SavedContext(*this, DC);
5125 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name))
5130 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
5131 QualType R = TInfo->getType();
5133 if (!R->isFunctionType() && DiagnoseClassNameShadow(DC, NameInfo))
5134 // If this is a typedef, we'll end up spewing multiple diagnostics.
5135 // Just return early; it's safer. If this is a function, let the
5136 // "constructor cannot have a return type" diagnostic handle it.
5137 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
5140 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
5141 UPPC_DeclarationType))
5144 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
5147 // See if this is a redefinition of a variable in the same scope.
5148 if (!D.getCXXScopeSpec().isSet()) {
5149 bool IsLinkageLookup = false;
5150 bool CreateBuiltins = false;
5152 // If the declaration we're planning to build will be a function
5153 // or object with linkage, then look for another declaration with
5154 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6).
5156 // If the declaration we're planning to build will be declared with
5157 // external linkage in the translation unit, create any builtin with
5159 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
5161 else if (CurContext->isFunctionOrMethod() &&
5162 (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern ||
5163 R->isFunctionType())) {
5164 IsLinkageLookup = true;
5166 CurContext->getEnclosingNamespaceContext()->isTranslationUnit();
5167 } else if (CurContext->getRedeclContext()->isTranslationUnit() &&
5168 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
5169 CreateBuiltins = true;
5171 if (IsLinkageLookup)
5172 Previous.clear(LookupRedeclarationWithLinkage);
5174 LookupName(Previous, S, CreateBuiltins);
5175 } else { // Something like "int foo::x;"
5176 LookupQualifiedName(Previous, DC);
5178 // C++ [dcl.meaning]p1:
5179 // When the declarator-id is qualified, the declaration shall refer to a
5180 // previously declared member of the class or namespace to which the
5181 // qualifier refers (or, in the case of a namespace, of an element of the
5182 // inline namespace set of that namespace (7.3.1)) or to a specialization
5185 // Note that we already checked the context above, and that we do not have
5186 // enough information to make sure that Previous contains the declaration
5187 // we want to match. For example, given:
5194 // void X::f(int) { } // ill-formed
5196 // In this case, Previous will point to the overload set
5197 // containing the two f's declared in X, but neither of them
5200 // C++ [dcl.meaning]p1:
5201 // [...] the member shall not merely have been introduced by a
5202 // using-declaration in the scope of the class or namespace nominated by
5203 // the nested-name-specifier of the declarator-id.
5204 RemoveUsingDecls(Previous);
5207 if (Previous.isSingleResult() &&
5208 Previous.getFoundDecl()->isTemplateParameter()) {
5209 // Maybe we will complain about the shadowed template parameter.
5210 if (!D.isInvalidType())
5211 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
5212 Previous.getFoundDecl());
5214 // Just pretend that we didn't see the previous declaration.
5218 // In C++, the previous declaration we find might be a tag type
5219 // (class or enum). In this case, the new declaration will hide the
5220 // tag type. Note that this does does not apply if we're declaring a
5221 // typedef (C++ [dcl.typedef]p4).
5222 if (Previous.isSingleTagDecl() &&
5223 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef)
5226 // Check that there are no default arguments other than in the parameters
5227 // of a function declaration (C++ only).
5228 if (getLangOpts().CPlusPlus)
5229 CheckExtraCXXDefaultArguments(D);
5231 if (D.getDeclSpec().isConceptSpecified()) {
5232 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
5233 // applied only to the definition of a function template or variable
5234 // template, declared in namespace scope
5235 if (!TemplateParamLists.size()) {
5236 Diag(D.getDeclSpec().getConceptSpecLoc(),
5237 diag:: err_concept_wrong_decl_kind);
5241 if (!DC->getRedeclContext()->isFileContext()) {
5242 Diag(D.getIdentifierLoc(),
5243 diag::err_concept_decls_may_only_appear_in_namespace_scope);
5250 bool AddToScope = true;
5251 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
5252 if (TemplateParamLists.size()) {
5253 Diag(D.getIdentifierLoc(), diag::err_template_typedef);
5257 New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous);
5258 } else if (R->isFunctionType()) {
5259 New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous,
5263 New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists,
5270 // If this has an identifier and is not a function template specialization,
5271 // add it to the scope stack.
5272 if (New->getDeclName() && AddToScope) {
5273 // Only make a locally-scoped extern declaration visible if it is the first
5274 // declaration of this entity. Qualified lookup for such an entity should
5275 // only find this declaration if there is no visible declaration of it.
5276 bool AddToContext = !D.isRedeclaration() || !New->isLocalExternDecl();
5277 PushOnScopeChains(New, S, AddToContext);
5279 CurContext->addHiddenDecl(New);
5282 if (isInOpenMPDeclareTargetContext())
5283 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
5288 /// Helper method to turn variable array types into constant array
5289 /// types in certain situations which would otherwise be errors (for
5290 /// GCC compatibility).
5291 static QualType TryToFixInvalidVariablyModifiedType(QualType T,
5292 ASTContext &Context,
5293 bool &SizeIsNegative,
5294 llvm::APSInt &Oversized) {
5295 // This method tries to turn a variable array into a constant
5296 // array even when the size isn't an ICE. This is necessary
5297 // for compatibility with code that depends on gcc's buggy
5298 // constant expression folding, like struct {char x[(int)(char*)2];}
5299 SizeIsNegative = false;
5302 if (T->isDependentType())
5305 QualifierCollector Qs;
5306 const Type *Ty = Qs.strip(T);
5308 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) {
5309 QualType Pointee = PTy->getPointeeType();
5310 QualType FixedType =
5311 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative,
5313 if (FixedType.isNull()) return FixedType;
5314 FixedType = Context.getPointerType(FixedType);
5315 return Qs.apply(Context, FixedType);
5317 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) {
5318 QualType Inner = PTy->getInnerType();
5319 QualType FixedType =
5320 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative,
5322 if (FixedType.isNull()) return FixedType;
5323 FixedType = Context.getParenType(FixedType);
5324 return Qs.apply(Context, FixedType);
5327 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T);
5330 // FIXME: We should probably handle this case
5331 if (VLATy->getElementType()->isVariablyModifiedType())
5335 if (!VLATy->getSizeExpr() ||
5336 !VLATy->getSizeExpr()->EvaluateAsInt(Res, Context))
5339 // Check whether the array size is negative.
5340 if (Res.isSigned() && Res.isNegative()) {
5341 SizeIsNegative = true;
5345 // Check whether the array is too large to be addressed.
5346 unsigned ActiveSizeBits
5347 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(),
5349 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
5354 return Context.getConstantArrayType(VLATy->getElementType(),
5355 Res, ArrayType::Normal, 0);
5359 FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) {
5360 SrcTL = SrcTL.getUnqualifiedLoc();
5361 DstTL = DstTL.getUnqualifiedLoc();
5362 if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) {
5363 PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>();
5364 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(),
5365 DstPTL.getPointeeLoc());
5366 DstPTL.setStarLoc(SrcPTL.getStarLoc());
5369 if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) {
5370 ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>();
5371 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(),
5372 DstPTL.getInnerLoc());
5373 DstPTL.setLParenLoc(SrcPTL.getLParenLoc());
5374 DstPTL.setRParenLoc(SrcPTL.getRParenLoc());
5377 ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>();
5378 ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>();
5379 TypeLoc SrcElemTL = SrcATL.getElementLoc();
5380 TypeLoc DstElemTL = DstATL.getElementLoc();
5381 DstElemTL.initializeFullCopy(SrcElemTL);
5382 DstATL.setLBracketLoc(SrcATL.getLBracketLoc());
5383 DstATL.setSizeExpr(SrcATL.getSizeExpr());
5384 DstATL.setRBracketLoc(SrcATL.getRBracketLoc());
5387 /// Helper method to turn variable array types into constant array
5388 /// types in certain situations which would otherwise be errors (for
5389 /// GCC compatibility).
5390 static TypeSourceInfo*
5391 TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo,
5392 ASTContext &Context,
5393 bool &SizeIsNegative,
5394 llvm::APSInt &Oversized) {
5396 = TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context,
5397 SizeIsNegative, Oversized);
5398 if (FixedTy.isNull())
5400 TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy);
5401 FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(),
5402 FixedTInfo->getTypeLoc());
5406 /// \brief Register the given locally-scoped extern "C" declaration so
5407 /// that it can be found later for redeclarations. We include any extern "C"
5408 /// declaration that is not visible in the translation unit here, not just
5409 /// function-scope declarations.
5411 Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) {
5412 if (!getLangOpts().CPlusPlus &&
5413 ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit())
5414 // Don't need to track declarations in the TU in C.
5417 // Note that we have a locally-scoped external with this name.
5418 Context.getExternCContextDecl()->makeDeclVisibleInContext(ND);
5421 NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) {
5422 // FIXME: We can have multiple results via __attribute__((overloadable)).
5423 auto Result = Context.getExternCContextDecl()->lookup(Name);
5424 return Result.empty() ? nullptr : *Result.begin();
5427 /// \brief Diagnose function specifiers on a declaration of an identifier that
5428 /// does not identify a function.
5429 void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) {
5430 // FIXME: We should probably indicate the identifier in question to avoid
5431 // confusion for constructs like "virtual int a(), b;"
5432 if (DS.isVirtualSpecified())
5433 Diag(DS.getVirtualSpecLoc(),
5434 diag::err_virtual_non_function);
5436 if (DS.isExplicitSpecified())
5437 Diag(DS.getExplicitSpecLoc(),
5438 diag::err_explicit_non_function);
5440 if (DS.isNoreturnSpecified())
5441 Diag(DS.getNoreturnSpecLoc(),
5442 diag::err_noreturn_non_function);
5446 Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
5447 TypeSourceInfo *TInfo, LookupResult &Previous) {
5448 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1).
5449 if (D.getCXXScopeSpec().isSet()) {
5450 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator)
5451 << D.getCXXScopeSpec().getRange();
5453 // Pretend we didn't see the scope specifier.
5458 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5460 if (D.getDeclSpec().isInlineSpecified())
5461 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
5462 << getLangOpts().CPlusPlus1z;
5463 if (D.getDeclSpec().isConstexprSpecified())
5464 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr)
5466 if (D.getDeclSpec().isConceptSpecified())
5467 Diag(D.getDeclSpec().getConceptSpecLoc(),
5468 diag::err_concept_wrong_decl_kind);
5470 if (D.getName().Kind != UnqualifiedId::IK_Identifier) {
5471 if (D.getName().Kind == UnqualifiedId::IK_DeductionGuideName)
5472 Diag(D.getName().StartLocation,
5473 diag::err_deduction_guide_invalid_specifier)
5476 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier)
5477 << D.getName().getSourceRange();
5481 TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo);
5482 if (!NewTD) return nullptr;
5484 // Handle attributes prior to checking for duplicates in MergeVarDecl
5485 ProcessDeclAttributes(S, NewTD, D);
5487 CheckTypedefForVariablyModifiedType(S, NewTD);
5489 bool Redeclaration = D.isRedeclaration();
5490 NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration);
5491 D.setRedeclaration(Redeclaration);
5496 Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) {
5497 // C99 6.7.7p2: If a typedef name specifies a variably modified type
5498 // then it shall have block scope.
5499 // Note that variably modified types must be fixed before merging the decl so
5500 // that redeclarations will match.
5501 TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo();
5502 QualType T = TInfo->getType();
5503 if (T->isVariablyModifiedType()) {
5504 getCurFunction()->setHasBranchProtectedScope();
5506 if (S->getFnParent() == nullptr) {
5507 bool SizeIsNegative;
5508 llvm::APSInt Oversized;
5509 TypeSourceInfo *FixedTInfo =
5510 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
5514 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size);
5515 NewTD->setTypeSourceInfo(FixedTInfo);
5518 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size);
5519 else if (T->isVariableArrayType())
5520 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope);
5521 else if (Oversized.getBoolValue())
5522 Diag(NewTD->getLocation(), diag::err_array_too_large)
5523 << Oversized.toString(10);
5525 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope);
5526 NewTD->setInvalidDecl();
5532 /// ActOnTypedefNameDecl - Perform semantic checking for a declaration which
5533 /// declares a typedef-name, either using the 'typedef' type specifier or via
5534 /// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'.
5536 Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD,
5537 LookupResult &Previous, bool &Redeclaration) {
5539 // Find the shadowed declaration before filtering for scope.
5540 NamedDecl *ShadowedDecl = getShadowedDeclaration(NewTD, Previous);
5542 // Merge the decl with the existing one if appropriate. If the decl is
5543 // in an outer scope, it isn't the same thing.
5544 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/false,
5545 /*AllowInlineNamespace*/false);
5546 filterNonConflictingPreviousTypedefDecls(*this, NewTD, Previous);
5547 if (!Previous.empty()) {
5548 Redeclaration = true;
5549 MergeTypedefNameDecl(S, NewTD, Previous);
5552 if (ShadowedDecl && !Redeclaration)
5553 CheckShadow(NewTD, ShadowedDecl, Previous);
5555 // If this is the C FILE type, notify the AST context.
5556 if (IdentifierInfo *II = NewTD->getIdentifier())
5557 if (!NewTD->isInvalidDecl() &&
5558 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
5559 if (II->isStr("FILE"))
5560 Context.setFILEDecl(NewTD);
5561 else if (II->isStr("jmp_buf"))
5562 Context.setjmp_bufDecl(NewTD);
5563 else if (II->isStr("sigjmp_buf"))
5564 Context.setsigjmp_bufDecl(NewTD);
5565 else if (II->isStr("ucontext_t"))
5566 Context.setucontext_tDecl(NewTD);
5572 /// \brief Determines whether the given declaration is an out-of-scope
5573 /// previous declaration.
5575 /// This routine should be invoked when name lookup has found a
5576 /// previous declaration (PrevDecl) that is not in the scope where a
5577 /// new declaration by the same name is being introduced. If the new
5578 /// declaration occurs in a local scope, previous declarations with
5579 /// linkage may still be considered previous declarations (C99
5580 /// 6.2.2p4-5, C++ [basic.link]p6).
5582 /// \param PrevDecl the previous declaration found by name
5585 /// \param DC the context in which the new declaration is being
5588 /// \returns true if PrevDecl is an out-of-scope previous declaration
5589 /// for a new delcaration with the same name.
5591 isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC,
5592 ASTContext &Context) {
5596 if (!PrevDecl->hasLinkage())
5599 if (Context.getLangOpts().CPlusPlus) {
5600 // C++ [basic.link]p6:
5601 // If there is a visible declaration of an entity with linkage
5602 // having the same name and type, ignoring entities declared
5603 // outside the innermost enclosing namespace scope, the block
5604 // scope declaration declares that same entity and receives the
5605 // linkage of the previous declaration.
5606 DeclContext *OuterContext = DC->getRedeclContext();
5607 if (!OuterContext->isFunctionOrMethod())
5608 // This rule only applies to block-scope declarations.
5611 DeclContext *PrevOuterContext = PrevDecl->getDeclContext();
5612 if (PrevOuterContext->isRecord())
5613 // We found a member function: ignore it.
5616 // Find the innermost enclosing namespace for the new and
5617 // previous declarations.
5618 OuterContext = OuterContext->getEnclosingNamespaceContext();
5619 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext();
5621 // The previous declaration is in a different namespace, so it
5622 // isn't the same function.
5623 if (!OuterContext->Equals(PrevOuterContext))
5630 static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) {
5631 CXXScopeSpec &SS = D.getCXXScopeSpec();
5632 if (!SS.isSet()) return;
5633 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext()));
5636 bool Sema::inferObjCARCLifetime(ValueDecl *decl) {
5637 QualType type = decl->getType();
5638 Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime();
5639 if (lifetime == Qualifiers::OCL_Autoreleasing) {
5640 // Various kinds of declaration aren't allowed to be __autoreleasing.
5641 unsigned kind = -1U;
5642 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5643 if (var->hasAttr<BlocksAttr>())
5644 kind = 0; // __block
5645 else if (!var->hasLocalStorage())
5647 } else if (isa<ObjCIvarDecl>(decl)) {
5649 } else if (isa<FieldDecl>(decl)) {
5654 Diag(decl->getLocation(), diag::err_arc_autoreleasing_var)
5657 } else if (lifetime == Qualifiers::OCL_None) {
5658 // Try to infer lifetime.
5659 if (!type->isObjCLifetimeType())
5662 lifetime = type->getObjCARCImplicitLifetime();
5663 type = Context.getLifetimeQualifiedType(type, lifetime);
5664 decl->setType(type);
5667 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5668 // Thread-local variables cannot have lifetime.
5669 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone &&
5670 var->getTLSKind()) {
5671 Diag(var->getLocation(), diag::err_arc_thread_ownership)
5680 static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) {
5681 // Ensure that an auto decl is deduced otherwise the checks below might cache
5682 // the wrong linkage.
5683 assert(S.ParsingInitForAutoVars.count(&ND) == 0);
5685 // 'weak' only applies to declarations with external linkage.
5686 if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) {
5687 if (!ND.isExternallyVisible()) {
5688 S.Diag(Attr->getLocation(), diag::err_attribute_weak_static);
5689 ND.dropAttr<WeakAttr>();
5692 if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) {
5693 if (ND.isExternallyVisible()) {
5694 S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static);
5695 ND.dropAttr<WeakRefAttr>();
5696 ND.dropAttr<AliasAttr>();
5700 if (auto *VD = dyn_cast<VarDecl>(&ND)) {
5701 if (VD->hasInit()) {
5702 if (const auto *Attr = VD->getAttr<AliasAttr>()) {
5703 assert(VD->isThisDeclarationADefinition() &&
5704 !VD->isExternallyVisible() && "Broken AliasAttr handled late!");
5705 S.Diag(Attr->getLocation(), diag::err_alias_is_definition) << VD << 0;
5706 VD->dropAttr<AliasAttr>();
5711 // 'selectany' only applies to externally visible variable declarations.
5712 // It does not apply to functions.
5713 if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) {
5714 if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) {
5715 S.Diag(Attr->getLocation(),
5716 diag::err_attribute_selectany_non_extern_data);
5717 ND.dropAttr<SelectAnyAttr>();
5721 if (const InheritableAttr *Attr = getDLLAttr(&ND)) {
5722 // dll attributes require external linkage. Static locals may have external
5723 // linkage but still cannot be explicitly imported or exported.
5724 auto *VD = dyn_cast<VarDecl>(&ND);
5725 if (!ND.isExternallyVisible() || (VD && VD->isStaticLocal())) {
5726 S.Diag(ND.getLocation(), diag::err_attribute_dll_not_extern)
5728 ND.setInvalidDecl();
5732 // Virtual functions cannot be marked as 'notail'.
5733 if (auto *Attr = ND.getAttr<NotTailCalledAttr>())
5734 if (auto *MD = dyn_cast<CXXMethodDecl>(&ND))
5735 if (MD->isVirtual()) {
5736 S.Diag(ND.getLocation(),
5737 diag::err_invalid_attribute_on_virtual_function)
5739 ND.dropAttr<NotTailCalledAttr>();
5743 static void checkDLLAttributeRedeclaration(Sema &S, NamedDecl *OldDecl,
5745 bool IsSpecialization,
5746 bool IsDefinition) {
5747 if (OldDecl->isInvalidDecl())
5750 bool IsTemplate = false;
5751 if (TemplateDecl *OldTD = dyn_cast<TemplateDecl>(OldDecl)) {
5752 OldDecl = OldTD->getTemplatedDecl();
5754 if (!IsSpecialization)
5755 IsDefinition = false;
5757 if (TemplateDecl *NewTD = dyn_cast<TemplateDecl>(NewDecl)) {
5758 NewDecl = NewTD->getTemplatedDecl();
5762 if (!OldDecl || !NewDecl)
5765 const DLLImportAttr *OldImportAttr = OldDecl->getAttr<DLLImportAttr>();
5766 const DLLExportAttr *OldExportAttr = OldDecl->getAttr<DLLExportAttr>();
5767 const DLLImportAttr *NewImportAttr = NewDecl->getAttr<DLLImportAttr>();
5768 const DLLExportAttr *NewExportAttr = NewDecl->getAttr<DLLExportAttr>();
5770 // dllimport and dllexport are inheritable attributes so we have to exclude
5771 // inherited attribute instances.
5772 bool HasNewAttr = (NewImportAttr && !NewImportAttr->isInherited()) ||
5773 (NewExportAttr && !NewExportAttr->isInherited());
5775 // A redeclaration is not allowed to add a dllimport or dllexport attribute,
5776 // the only exception being explicit specializations.
5777 // Implicitly generated declarations are also excluded for now because there
5778 // is no other way to switch these to use dllimport or dllexport.
5779 bool AddsAttr = !(OldImportAttr || OldExportAttr) && HasNewAttr;
5781 if (AddsAttr && !IsSpecialization && !OldDecl->isImplicit()) {
5782 // Allow with a warning for free functions and global variables.
5783 bool JustWarn = false;
5784 if (!OldDecl->isCXXClassMember()) {
5785 auto *VD = dyn_cast<VarDecl>(OldDecl);
5786 if (VD && !VD->getDescribedVarTemplate())
5788 auto *FD = dyn_cast<FunctionDecl>(OldDecl);
5789 if (FD && FD->getTemplatedKind() == FunctionDecl::TK_NonTemplate)
5793 // We cannot change a declaration that's been used because IR has already
5794 // been emitted. Dllimported functions will still work though (modulo
5795 // address equality) as they can use the thunk.
5796 if (OldDecl->isUsed())
5797 if (!isa<FunctionDecl>(OldDecl) || !NewImportAttr)
5800 unsigned DiagID = JustWarn ? diag::warn_attribute_dll_redeclaration
5801 : diag::err_attribute_dll_redeclaration;
5802 S.Diag(NewDecl->getLocation(), DiagID)
5804 << (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr);
5805 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5807 NewDecl->setInvalidDecl();
5812 // A redeclaration is not allowed to drop a dllimport attribute, the only
5813 // exceptions being inline function definitions (except for function
5814 // templates), local extern declarations, qualified friend declarations or
5815 // special MSVC extension: in the last case, the declaration is treated as if
5816 // it were marked dllexport.
5817 bool IsInline = false, IsStaticDataMember = false, IsQualifiedFriend = false;
5818 bool IsMicrosoft = S.Context.getTargetInfo().getCXXABI().isMicrosoft();
5819 if (const auto *VD = dyn_cast<VarDecl>(NewDecl)) {
5820 // Ignore static data because out-of-line definitions are diagnosed
5822 IsStaticDataMember = VD->isStaticDataMember();
5823 IsDefinition = VD->isThisDeclarationADefinition(S.Context) !=
5824 VarDecl::DeclarationOnly;
5825 } else if (const auto *FD = dyn_cast<FunctionDecl>(NewDecl)) {
5826 IsInline = FD->isInlined();
5827 IsQualifiedFriend = FD->getQualifier() &&
5828 FD->getFriendObjectKind() == Decl::FOK_Declared;
5831 if (OldImportAttr && !HasNewAttr &&
5832 (!IsInline || (IsMicrosoft && IsTemplate)) && !IsStaticDataMember &&
5833 !NewDecl->isLocalExternDecl() && !IsQualifiedFriend) {
5834 if (IsMicrosoft && IsDefinition) {
5835 S.Diag(NewDecl->getLocation(),
5836 diag::warn_redeclaration_without_import_attribute)
5838 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5839 NewDecl->dropAttr<DLLImportAttr>();
5840 NewDecl->addAttr(::new (S.Context) DLLExportAttr(
5841 NewImportAttr->getRange(), S.Context,
5842 NewImportAttr->getSpellingListIndex()));
5844 S.Diag(NewDecl->getLocation(),
5845 diag::warn_redeclaration_without_attribute_prev_attribute_ignored)
5846 << NewDecl << OldImportAttr;
5847 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5848 S.Diag(OldImportAttr->getLocation(), diag::note_previous_attribute);
5849 OldDecl->dropAttr<DLLImportAttr>();
5850 NewDecl->dropAttr<DLLImportAttr>();
5852 } else if (IsInline && OldImportAttr && !IsMicrosoft) {
5853 // In MinGW, seeing a function declared inline drops the dllimport attribute.
5854 OldDecl->dropAttr<DLLImportAttr>();
5855 NewDecl->dropAttr<DLLImportAttr>();
5856 S.Diag(NewDecl->getLocation(),
5857 diag::warn_dllimport_dropped_from_inline_function)
5858 << NewDecl << OldImportAttr;
5862 /// Given that we are within the definition of the given function,
5863 /// will that definition behave like C99's 'inline', where the
5864 /// definition is discarded except for optimization purposes?
5865 static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) {
5866 // Try to avoid calling GetGVALinkageForFunction.
5868 // All cases of this require the 'inline' keyword.
5869 if (!FD->isInlined()) return false;
5871 // This is only possible in C++ with the gnu_inline attribute.
5872 if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>())
5875 // Okay, go ahead and call the relatively-more-expensive function.
5876 return S.Context.GetGVALinkageForFunction(FD) == GVA_AvailableExternally;
5879 /// Determine whether a variable is extern "C" prior to attaching
5880 /// an initializer. We can't just call isExternC() here, because that
5881 /// will also compute and cache whether the declaration is externally
5882 /// visible, which might change when we attach the initializer.
5884 /// This can only be used if the declaration is known to not be a
5885 /// redeclaration of an internal linkage declaration.
5891 /// Attaching the initializer here makes this declaration not externally
5892 /// visible, because its type has internal linkage.
5894 /// FIXME: This is a hack.
5895 template<typename T>
5896 static bool isIncompleteDeclExternC(Sema &S, const T *D) {
5897 if (S.getLangOpts().CPlusPlus) {
5898 // In C++, the overloadable attribute negates the effects of extern "C".
5899 if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>())
5902 // So do CUDA's host/device attributes.
5903 if (S.getLangOpts().CUDA && (D->template hasAttr<CUDADeviceAttr>() ||
5904 D->template hasAttr<CUDAHostAttr>()))
5907 return D->isExternC();
5910 static bool shouldConsiderLinkage(const VarDecl *VD) {
5911 const DeclContext *DC = VD->getDeclContext()->getRedeclContext();
5912 if (DC->isFunctionOrMethod() || isa<OMPDeclareReductionDecl>(DC))
5913 return VD->hasExternalStorage();
5914 if (DC->isFileContext())
5918 llvm_unreachable("Unexpected context");
5921 static bool shouldConsiderLinkage(const FunctionDecl *FD) {
5922 const DeclContext *DC = FD->getDeclContext()->getRedeclContext();
5923 if (DC->isFileContext() || DC->isFunctionOrMethod() ||
5924 isa<OMPDeclareReductionDecl>(DC))
5928 llvm_unreachable("Unexpected context");
5931 static bool hasParsedAttr(Scope *S, const AttributeList *AttrList,
5932 AttributeList::Kind Kind) {
5933 for (const AttributeList *L = AttrList; L; L = L->getNext())
5934 if (L->getKind() == Kind)
5939 static bool hasParsedAttr(Scope *S, const Declarator &PD,
5940 AttributeList::Kind Kind) {
5941 // Check decl attributes on the DeclSpec.
5942 if (hasParsedAttr(S, PD.getDeclSpec().getAttributes().getList(), Kind))
5945 // Walk the declarator structure, checking decl attributes that were in a type
5946 // position to the decl itself.
5947 for (unsigned I = 0, E = PD.getNumTypeObjects(); I != E; ++I) {
5948 if (hasParsedAttr(S, PD.getTypeObject(I).getAttrs(), Kind))
5952 // Finally, check attributes on the decl itself.
5953 return hasParsedAttr(S, PD.getAttributes(), Kind);
5956 /// Adjust the \c DeclContext for a function or variable that might be a
5957 /// function-local external declaration.
5958 bool Sema::adjustContextForLocalExternDecl(DeclContext *&DC) {
5959 if (!DC->isFunctionOrMethod())
5962 // If this is a local extern function or variable declared within a function
5963 // template, don't add it into the enclosing namespace scope until it is
5964 // instantiated; it might have a dependent type right now.
5965 if (DC->isDependentContext())
5968 // C++11 [basic.link]p7:
5969 // When a block scope declaration of an entity with linkage is not found to
5970 // refer to some other declaration, then that entity is a member of the
5971 // innermost enclosing namespace.
5973 // Per C++11 [namespace.def]p6, the innermost enclosing namespace is a
5974 // semantically-enclosing namespace, not a lexically-enclosing one.
5975 while (!DC->isFileContext() && !isa<LinkageSpecDecl>(DC))
5976 DC = DC->getParent();
5980 /// \brief Returns true if given declaration has external C language linkage.
5981 static bool isDeclExternC(const Decl *D) {
5982 if (const auto *FD = dyn_cast<FunctionDecl>(D))
5983 return FD->isExternC();
5984 if (const auto *VD = dyn_cast<VarDecl>(D))
5985 return VD->isExternC();
5987 llvm_unreachable("Unknown type of decl!");
5990 NamedDecl *Sema::ActOnVariableDeclarator(
5991 Scope *S, Declarator &D, DeclContext *DC, TypeSourceInfo *TInfo,
5992 LookupResult &Previous, MultiTemplateParamsArg TemplateParamLists,
5993 bool &AddToScope, ArrayRef<BindingDecl *> Bindings) {
5994 QualType R = TInfo->getType();
5995 DeclarationName Name = GetNameForDeclarator(D).getName();
5997 IdentifierInfo *II = Name.getAsIdentifierInfo();
5999 if (D.isDecompositionDeclarator()) {
6001 // Take the name of the first declarator as our name for diagnostic
6003 auto &Decomp = D.getDecompositionDeclarator();
6004 if (!Decomp.bindings().empty()) {
6005 II = Decomp.bindings()[0].Name;
6009 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) << Name;
6013 if (getLangOpts().OpenCL) {
6014 // OpenCL v2.0 s6.9.b - Image type can only be used as a function argument.
6015 // OpenCL v2.0 s6.13.16.1 - Pipe type can only be used as a function
6017 if (R->isImageType() || R->isPipeType()) {
6018 Diag(D.getIdentifierLoc(),
6019 diag::err_opencl_type_can_only_be_used_as_function_parameter)
6025 // OpenCL v1.2 s6.9.r:
6026 // The event type cannot be used to declare a program scope variable.
6027 // OpenCL v2.0 s6.9.q:
6028 // The clk_event_t and reserve_id_t types cannot be declared in program scope.
6029 if (NULL == S->getParent()) {
6030 if (R->isReserveIDT() || R->isClkEventT() || R->isEventT()) {
6031 Diag(D.getIdentifierLoc(),
6032 diag::err_invalid_type_for_program_scope_var) << R;
6038 // OpenCL v1.0 s6.8.a.3: Pointers to functions are not allowed.
6040 while (NR->isPointerType()) {
6041 if (NR->isFunctionPointerType()) {
6042 Diag(D.getIdentifierLoc(), diag::err_opencl_function_pointer_variable);
6046 NR = NR->getPointeeType();
6049 if (!getOpenCLOptions().isEnabled("cl_khr_fp16")) {
6050 // OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and
6051 // half array type (unless the cl_khr_fp16 extension is enabled).
6052 if (Context.getBaseElementType(R)->isHalfType()) {
6053 Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R;
6058 // OpenCL v1.2 s6.9.b p4:
6059 // The sampler type cannot be used with the __local and __global address
6060 // space qualifiers.
6061 if (R->isSamplerT() && (R.getAddressSpace() == LangAS::opencl_local ||
6062 R.getAddressSpace() == LangAS::opencl_global)) {
6063 Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace);
6066 // OpenCL v1.2 s6.9.r:
6067 // The event type cannot be used with the __local, __constant and __global
6068 // address space qualifiers.
6069 if (R->isEventT()) {
6070 if (R.getAddressSpace()) {
6071 Diag(D.getLocStart(), diag::err_event_t_addr_space_qual);
6077 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec();
6078 StorageClass SC = StorageClassSpecToVarDeclStorageClass(D.getDeclSpec());
6080 // dllimport globals without explicit storage class are treated as extern. We
6081 // have to change the storage class this early to get the right DeclContext.
6082 if (SC == SC_None && !DC->isRecord() &&
6083 hasParsedAttr(S, D, AttributeList::AT_DLLImport) &&
6084 !hasParsedAttr(S, D, AttributeList::AT_DLLExport))
6087 DeclContext *OriginalDC = DC;
6088 bool IsLocalExternDecl = SC == SC_Extern &&
6089 adjustContextForLocalExternDecl(DC);
6091 if (SCSpec == DeclSpec::SCS_mutable) {
6092 // mutable can only appear on non-static class members, so it's always
6094 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember);
6099 if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register &&
6100 !D.getAsmLabel() && !getSourceManager().isInSystemMacro(
6101 D.getDeclSpec().getStorageClassSpecLoc())) {
6102 // In C++11, the 'register' storage class specifier is deprecated.
6103 // Suppress the warning in system macros, it's used in macros in some
6104 // popular C system headers, such as in glibc's htonl() macro.
6105 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6106 getLangOpts().CPlusPlus1z ? diag::ext_register_storage_class
6107 : diag::warn_deprecated_register)
6108 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6111 DiagnoseFunctionSpecifiers(D.getDeclSpec());
6113 if (!DC->isRecord() && S->getFnParent() == nullptr) {
6114 // C99 6.9p2: The storage-class specifiers auto and register shall not
6115 // appear in the declaration specifiers in an external declaration.
6116 // Global Register+Asm is a GNU extension we support.
6117 if (SC == SC_Auto || (SC == SC_Register && !D.getAsmLabel())) {
6118 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope);
6123 bool IsMemberSpecialization = false;
6124 bool IsVariableTemplateSpecialization = false;
6125 bool IsPartialSpecialization = false;
6126 bool IsVariableTemplate = false;
6127 VarDecl *NewVD = nullptr;
6128 VarTemplateDecl *NewTemplate = nullptr;
6129 TemplateParameterList *TemplateParams = nullptr;
6130 if (!getLangOpts().CPlusPlus) {
6131 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
6132 D.getIdentifierLoc(), II,
6135 if (R->getContainedDeducedType())
6136 ParsingInitForAutoVars.insert(NewVD);
6138 if (D.isInvalidType())
6139 NewVD->setInvalidDecl();
6141 bool Invalid = false;
6143 if (DC->isRecord() && !CurContext->isRecord()) {
6144 // This is an out-of-line definition of a static data member.
6149 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6150 diag::err_static_out_of_line)
6151 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6156 // [dcl.stc] p2: The auto or register specifiers shall be applied only
6157 // to names of variables declared in a block or to function parameters.
6158 // [dcl.stc] p6: The extern specifier cannot be used in the declaration
6161 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6162 diag::err_storage_class_for_static_member)
6163 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6165 case SC_PrivateExtern:
6166 llvm_unreachable("C storage class in c++!");
6170 if (SC == SC_Static && CurContext->isRecord()) {
6171 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) {
6172 if (RD->isLocalClass())
6173 Diag(D.getIdentifierLoc(),
6174 diag::err_static_data_member_not_allowed_in_local_class)
6175 << Name << RD->getDeclName();
6177 // C++98 [class.union]p1: If a union contains a static data member,
6178 // the program is ill-formed. C++11 drops this restriction.
6180 Diag(D.getIdentifierLoc(),
6181 getLangOpts().CPlusPlus11
6182 ? diag::warn_cxx98_compat_static_data_member_in_union
6183 : diag::ext_static_data_member_in_union) << Name;
6184 // We conservatively disallow static data members in anonymous structs.
6185 else if (!RD->getDeclName())
6186 Diag(D.getIdentifierLoc(),
6187 diag::err_static_data_member_not_allowed_in_anon_struct)
6188 << Name << RD->isUnion();
6192 // Match up the template parameter lists with the scope specifier, then
6193 // determine whether we have a template or a template specialization.
6194 TemplateParams = MatchTemplateParametersToScopeSpecifier(
6195 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
6196 D.getCXXScopeSpec(),
6197 D.getName().getKind() == UnqualifiedId::IK_TemplateId
6198 ? D.getName().TemplateId
6201 /*never a friend*/ false, IsMemberSpecialization, Invalid);
6203 if (TemplateParams) {
6204 if (!TemplateParams->size() &&
6205 D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
6206 // There is an extraneous 'template<>' for this variable. Complain
6207 // about it, but allow the declaration of the variable.
6208 Diag(TemplateParams->getTemplateLoc(),
6209 diag::err_template_variable_noparams)
6211 << SourceRange(TemplateParams->getTemplateLoc(),
6212 TemplateParams->getRAngleLoc());
6213 TemplateParams = nullptr;
6215 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
6216 // This is an explicit specialization or a partial specialization.
6217 // FIXME: Check that we can declare a specialization here.
6218 IsVariableTemplateSpecialization = true;
6219 IsPartialSpecialization = TemplateParams->size() > 0;
6220 } else { // if (TemplateParams->size() > 0)
6221 // This is a template declaration.
6222 IsVariableTemplate = true;
6224 // Check that we can declare a template here.
6225 if (CheckTemplateDeclScope(S, TemplateParams))
6228 // Only C++1y supports variable templates (N3651).
6229 Diag(D.getIdentifierLoc(),
6230 getLangOpts().CPlusPlus14
6231 ? diag::warn_cxx11_compat_variable_template
6232 : diag::ext_variable_template);
6237 (Invalid || D.getName().getKind() != UnqualifiedId::IK_TemplateId) &&
6238 "should have a 'template<>' for this decl");
6241 if (IsVariableTemplateSpecialization) {
6242 SourceLocation TemplateKWLoc =
6243 TemplateParamLists.size() > 0
6244 ? TemplateParamLists[0]->getTemplateLoc()
6246 DeclResult Res = ActOnVarTemplateSpecialization(
6247 S, D, TInfo, TemplateKWLoc, TemplateParams, SC,
6248 IsPartialSpecialization);
6249 if (Res.isInvalid())
6251 NewVD = cast<VarDecl>(Res.get());
6253 } else if (D.isDecompositionDeclarator()) {
6254 NewVD = DecompositionDecl::Create(Context, DC, D.getLocStart(),
6255 D.getIdentifierLoc(), R, TInfo, SC,
6258 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
6259 D.getIdentifierLoc(), II, R, TInfo, SC);
6261 // If this is supposed to be a variable template, create it as such.
6262 if (IsVariableTemplate) {
6264 VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name,
6265 TemplateParams, NewVD);
6266 NewVD->setDescribedVarTemplate(NewTemplate);
6269 // If this decl has an auto type in need of deduction, make a note of the
6270 // Decl so we can diagnose uses of it in its own initializer.
6271 if (R->getContainedDeducedType())
6272 ParsingInitForAutoVars.insert(NewVD);
6274 if (D.isInvalidType() || Invalid) {
6275 NewVD->setInvalidDecl();
6277 NewTemplate->setInvalidDecl();
6280 SetNestedNameSpecifier(NewVD, D);
6282 // If we have any template parameter lists that don't directly belong to
6283 // the variable (matching the scope specifier), store them.
6284 unsigned VDTemplateParamLists = TemplateParams ? 1 : 0;
6285 if (TemplateParamLists.size() > VDTemplateParamLists)
6286 NewVD->setTemplateParameterListsInfo(
6287 Context, TemplateParamLists.drop_back(VDTemplateParamLists));
6289 if (D.getDeclSpec().isConstexprSpecified()) {
6290 NewVD->setConstexpr(true);
6291 // C++1z [dcl.spec.constexpr]p1:
6292 // A static data member declared with the constexpr specifier is
6293 // implicitly an inline variable.
6294 if (NewVD->isStaticDataMember() && getLangOpts().CPlusPlus1z)
6295 NewVD->setImplicitlyInline();
6298 if (D.getDeclSpec().isConceptSpecified()) {
6299 if (VarTemplateDecl *VTD = NewVD->getDescribedVarTemplate())
6302 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
6303 // be declared with the thread_local, inline, friend, or constexpr
6304 // specifiers, [...]
6305 if (D.getDeclSpec().getThreadStorageClassSpec() == TSCS_thread_local) {
6306 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6307 diag::err_concept_decl_invalid_specifiers)
6309 NewVD->setInvalidDecl(true);
6312 if (D.getDeclSpec().isConstexprSpecified()) {
6313 Diag(D.getDeclSpec().getConstexprSpecLoc(),
6314 diag::err_concept_decl_invalid_specifiers)
6316 NewVD->setInvalidDecl(true);
6319 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
6320 // applied only to the definition of a function template or variable
6321 // template, declared in namespace scope.
6322 if (IsVariableTemplateSpecialization) {
6323 Diag(D.getDeclSpec().getConceptSpecLoc(),
6324 diag::err_concept_specified_specialization)
6325 << (IsPartialSpecialization ? 2 : 1);
6328 // C++ Concepts TS [dcl.spec.concept]p6: A variable concept has the
6329 // following restrictions:
6330 // - The declared type shall have the type bool.
6331 if (!Context.hasSameType(NewVD->getType(), Context.BoolTy) &&
6332 !NewVD->isInvalidDecl()) {
6333 Diag(D.getIdentifierLoc(), diag::err_variable_concept_bool_decl);
6334 NewVD->setInvalidDecl(true);
6339 if (D.getDeclSpec().isInlineSpecified()) {
6340 if (!getLangOpts().CPlusPlus) {
6341 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
6343 } else if (CurContext->isFunctionOrMethod()) {
6344 // 'inline' is not allowed on block scope variable declaration.
6345 Diag(D.getDeclSpec().getInlineSpecLoc(),
6346 diag::err_inline_declaration_block_scope) << Name
6347 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
6349 Diag(D.getDeclSpec().getInlineSpecLoc(),
6350 getLangOpts().CPlusPlus1z ? diag::warn_cxx14_compat_inline_variable
6351 : diag::ext_inline_variable);
6352 NewVD->setInlineSpecified();
6356 // Set the lexical context. If the declarator has a C++ scope specifier, the
6357 // lexical context will be different from the semantic context.
6358 NewVD->setLexicalDeclContext(CurContext);
6360 NewTemplate->setLexicalDeclContext(CurContext);
6362 if (IsLocalExternDecl) {
6363 if (D.isDecompositionDeclarator())
6364 for (auto *B : Bindings)
6365 B->setLocalExternDecl();
6367 NewVD->setLocalExternDecl();
6370 bool EmitTLSUnsupportedError = false;
6371 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) {
6372 // C++11 [dcl.stc]p4:
6373 // When thread_local is applied to a variable of block scope the
6374 // storage-class-specifier static is implied if it does not appear
6376 // Core issue: 'static' is not implied if the variable is declared
6378 if (NewVD->hasLocalStorage() &&
6379 (SCSpec != DeclSpec::SCS_unspecified ||
6380 TSCS != DeclSpec::TSCS_thread_local ||
6381 !DC->isFunctionOrMethod()))
6382 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6383 diag::err_thread_non_global)
6384 << DeclSpec::getSpecifierName(TSCS);
6385 else if (!Context.getTargetInfo().isTLSSupported()) {
6386 if (getLangOpts().CUDA) {
6387 // Postpone error emission until we've collected attributes required to
6388 // figure out whether it's a host or device variable and whether the
6389 // error should be ignored.
6390 EmitTLSUnsupportedError = true;
6391 // We still need to mark the variable as TLS so it shows up in AST with
6392 // proper storage class for other tools to use even if we're not going
6393 // to emit any code for it.
6394 NewVD->setTSCSpec(TSCS);
6396 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6397 diag::err_thread_unsupported);
6399 NewVD->setTSCSpec(TSCS);
6403 // An inline definition of a function with external linkage shall
6404 // not contain a definition of a modifiable object with static or
6405 // thread storage duration...
6406 // We only apply this when the function is required to be defined
6407 // elsewhere, i.e. when the function is not 'extern inline'. Note
6408 // that a local variable with thread storage duration still has to
6409 // be marked 'static'. Also note that it's possible to get these
6410 // semantics in C++ using __attribute__((gnu_inline)).
6411 if (SC == SC_Static && S->getFnParent() != nullptr &&
6412 !NewVD->getType().isConstQualified()) {
6413 FunctionDecl *CurFD = getCurFunctionDecl();
6414 if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) {
6415 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6416 diag::warn_static_local_in_extern_inline);
6417 MaybeSuggestAddingStaticToDecl(CurFD);
6421 if (D.getDeclSpec().isModulePrivateSpecified()) {
6422 if (IsVariableTemplateSpecialization)
6423 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6424 << (IsPartialSpecialization ? 1 : 0)
6425 << FixItHint::CreateRemoval(
6426 D.getDeclSpec().getModulePrivateSpecLoc());
6427 else if (IsMemberSpecialization)
6428 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6430 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6431 else if (NewVD->hasLocalStorage())
6432 Diag(NewVD->getLocation(), diag::err_module_private_local)
6433 << 0 << NewVD->getDeclName()
6434 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
6435 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6437 NewVD->setModulePrivate();
6439 NewTemplate->setModulePrivate();
6440 for (auto *B : Bindings)
6441 B->setModulePrivate();
6445 // Handle attributes prior to checking for duplicates in MergeVarDecl
6446 ProcessDeclAttributes(S, NewVD, D);
6448 if (getLangOpts().CUDA) {
6449 if (EmitTLSUnsupportedError && DeclAttrsMatchCUDAMode(getLangOpts(), NewVD))
6450 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6451 diag::err_thread_unsupported);
6452 // CUDA B.2.5: "__shared__ and __constant__ variables have implied static
6453 // storage [duration]."
6454 if (SC == SC_None && S->getFnParent() != nullptr &&
6455 (NewVD->hasAttr<CUDASharedAttr>() ||
6456 NewVD->hasAttr<CUDAConstantAttr>())) {
6457 NewVD->setStorageClass(SC_Static);
6461 // Ensure that dllimport globals without explicit storage class are treated as
6462 // extern. The storage class is set above using parsed attributes. Now we can
6463 // check the VarDecl itself.
6464 assert(!NewVD->hasAttr<DLLImportAttr>() ||
6465 NewVD->getAttr<DLLImportAttr>()->isInherited() ||
6466 NewVD->isStaticDataMember() || NewVD->getStorageClass() != SC_None);
6468 // In auto-retain/release, infer strong retension for variables of
6470 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD))
6471 NewVD->setInvalidDecl();
6473 // Handle GNU asm-label extension (encoded as an attribute).
6474 if (Expr *E = (Expr*)D.getAsmLabel()) {
6475 // The parser guarantees this is a string.
6476 StringLiteral *SE = cast<StringLiteral>(E);
6477 StringRef Label = SE->getString();
6478 if (S->getFnParent() != nullptr) {
6482 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label;
6485 // Local Named register
6486 if (!Context.getTargetInfo().isValidGCCRegisterName(Label) &&
6487 DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl()))
6488 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6492 case SC_PrivateExtern:
6495 } else if (SC == SC_Register) {
6496 // Global Named register
6497 if (DeclAttrsMatchCUDAMode(getLangOpts(), NewVD)) {
6498 const auto &TI = Context.getTargetInfo();
6499 bool HasSizeMismatch;
6501 if (!TI.isValidGCCRegisterName(Label))
6502 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6503 else if (!TI.validateGlobalRegisterVariable(Label,
6504 Context.getTypeSize(R),
6506 Diag(E->getExprLoc(), diag::err_asm_invalid_global_var_reg) << Label;
6507 else if (HasSizeMismatch)
6508 Diag(E->getExprLoc(), diag::err_asm_register_size_mismatch) << Label;
6511 if (!R->isIntegralType(Context) && !R->isPointerType()) {
6512 Diag(D.getLocStart(), diag::err_asm_bad_register_type);
6513 NewVD->setInvalidDecl(true);
6517 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0),
6518 Context, Label, 0));
6519 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
6520 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
6521 ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier());
6522 if (I != ExtnameUndeclaredIdentifiers.end()) {
6523 if (isDeclExternC(NewVD)) {
6524 NewVD->addAttr(I->second);
6525 ExtnameUndeclaredIdentifiers.erase(I);
6527 Diag(NewVD->getLocation(), diag::warn_redefine_extname_not_applied)
6528 << /*Variable*/1 << NewVD;
6532 // Find the shadowed declaration before filtering for scope.
6533 NamedDecl *ShadowedDecl = D.getCXXScopeSpec().isEmpty()
6534 ? getShadowedDeclaration(NewVD, Previous)
6537 // Don't consider existing declarations that are in a different
6538 // scope and are out-of-semantic-context declarations (if the new
6539 // declaration has linkage).
6540 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewVD),
6541 D.getCXXScopeSpec().isNotEmpty() ||
6542 IsMemberSpecialization ||
6543 IsVariableTemplateSpecialization);
6545 // Check whether the previous declaration is in the same block scope. This
6546 // affects whether we merge types with it, per C++11 [dcl.array]p3.
6547 if (getLangOpts().CPlusPlus &&
6548 NewVD->isLocalVarDecl() && NewVD->hasExternalStorage())
6549 NewVD->setPreviousDeclInSameBlockScope(
6550 Previous.isSingleResult() && !Previous.isShadowed() &&
6551 isDeclInScope(Previous.getFoundDecl(), OriginalDC, S, false));
6553 if (!getLangOpts().CPlusPlus) {
6554 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6556 // If this is an explicit specialization of a static data member, check it.
6557 if (IsMemberSpecialization && !NewVD->isInvalidDecl() &&
6558 CheckMemberSpecialization(NewVD, Previous))
6559 NewVD->setInvalidDecl();
6561 // Merge the decl with the existing one if appropriate.
6562 if (!Previous.empty()) {
6563 if (Previous.isSingleResult() &&
6564 isa<FieldDecl>(Previous.getFoundDecl()) &&
6565 D.getCXXScopeSpec().isSet()) {
6566 // The user tried to define a non-static data member
6567 // out-of-line (C++ [dcl.meaning]p1).
6568 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line)
6569 << D.getCXXScopeSpec().getRange();
6571 NewVD->setInvalidDecl();
6573 } else if (D.getCXXScopeSpec().isSet()) {
6574 // No previous declaration in the qualifying scope.
6575 Diag(D.getIdentifierLoc(), diag::err_no_member)
6576 << Name << computeDeclContext(D.getCXXScopeSpec(), true)
6577 << D.getCXXScopeSpec().getRange();
6578 NewVD->setInvalidDecl();
6581 if (!IsVariableTemplateSpecialization)
6582 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6584 // C++ Concepts TS [dcl.spec.concept]p7: A program shall not declare [...]
6585 // an explicit specialization (14.8.3) or a partial specialization of a
6586 // concept definition.
6587 if (IsVariableTemplateSpecialization &&
6588 !D.getDeclSpec().isConceptSpecified() && !Previous.empty() &&
6589 Previous.isSingleResult()) {
6590 NamedDecl *PreviousDecl = Previous.getFoundDecl();
6591 if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(PreviousDecl)) {
6592 if (VarTmpl->isConcept()) {
6593 Diag(NewVD->getLocation(), diag::err_concept_specialized)
6595 << (IsPartialSpecialization ? 2 /*partially specialized*/
6596 : 1 /*explicitly specialized*/);
6597 Diag(VarTmpl->getLocation(), diag::note_previous_declaration);
6598 NewVD->setInvalidDecl();
6604 VarTemplateDecl *PrevVarTemplate =
6605 NewVD->getPreviousDecl()
6606 ? NewVD->getPreviousDecl()->getDescribedVarTemplate()
6609 // Check the template parameter list of this declaration, possibly
6610 // merging in the template parameter list from the previous variable
6611 // template declaration.
6612 if (CheckTemplateParameterList(
6614 PrevVarTemplate ? PrevVarTemplate->getTemplateParameters()
6616 (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() &&
6617 DC->isDependentContext())
6618 ? TPC_ClassTemplateMember
6620 NewVD->setInvalidDecl();
6622 // If we are providing an explicit specialization of a static variable
6623 // template, make a note of that.
6624 if (PrevVarTemplate &&
6625 PrevVarTemplate->getInstantiatedFromMemberTemplate())
6626 PrevVarTemplate->setMemberSpecialization();
6630 // Diagnose shadowed variables iff this isn't a redeclaration.
6631 if (ShadowedDecl && !D.isRedeclaration())
6632 CheckShadow(NewVD, ShadowedDecl, Previous);
6634 ProcessPragmaWeak(S, NewVD);
6636 // If this is the first declaration of an extern C variable, update
6637 // the map of such variables.
6638 if (NewVD->isFirstDecl() && !NewVD->isInvalidDecl() &&
6639 isIncompleteDeclExternC(*this, NewVD))
6640 RegisterLocallyScopedExternCDecl(NewVD, S);
6642 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
6643 Decl *ManglingContextDecl;
6644 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
6645 NewVD->getDeclContext(), ManglingContextDecl)) {
6646 Context.setManglingNumber(
6647 NewVD, MCtx->getManglingNumber(
6648 NewVD, getMSManglingNumber(getLangOpts(), S)));
6649 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
6653 // Special handling of variable named 'main'.
6654 if (Name.getAsIdentifierInfo() && Name.getAsIdentifierInfo()->isStr("main") &&
6655 NewVD->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
6656 !getLangOpts().Freestanding && !NewVD->getDescribedVarTemplate()) {
6658 // C++ [basic.start.main]p3
6659 // A program that declares a variable main at global scope is ill-formed.
6660 if (getLangOpts().CPlusPlus)
6661 Diag(D.getLocStart(), diag::err_main_global_variable);
6663 // In C, and external-linkage variable named main results in undefined
6665 else if (NewVD->hasExternalFormalLinkage())
6666 Diag(D.getLocStart(), diag::warn_main_redefined);
6669 if (D.isRedeclaration() && !Previous.empty()) {
6670 checkDLLAttributeRedeclaration(
6671 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewVD,
6672 IsMemberSpecialization, D.isFunctionDefinition());
6676 if (NewVD->isInvalidDecl())
6677 NewTemplate->setInvalidDecl();
6678 ActOnDocumentableDecl(NewTemplate);
6685 /// Enum describing the %select options in diag::warn_decl_shadow.
6686 enum ShadowedDeclKind {
6695 /// Determine what kind of declaration we're shadowing.
6696 static ShadowedDeclKind computeShadowedDeclKind(const NamedDecl *ShadowedDecl,
6697 const DeclContext *OldDC) {
6698 if (isa<TypeAliasDecl>(ShadowedDecl))
6700 else if (isa<TypedefDecl>(ShadowedDecl))
6702 else if (isa<RecordDecl>(OldDC))
6703 return isa<FieldDecl>(ShadowedDecl) ? SDK_Field : SDK_StaticMember;
6705 return OldDC->isFileContext() ? SDK_Global : SDK_Local;
6708 /// Return the location of the capture if the given lambda captures the given
6709 /// variable \p VD, or an invalid source location otherwise.
6710 static SourceLocation getCaptureLocation(const LambdaScopeInfo *LSI,
6711 const VarDecl *VD) {
6712 for (const LambdaScopeInfo::Capture &Capture : LSI->Captures) {
6713 if (Capture.isVariableCapture() && Capture.getVariable() == VD)
6714 return Capture.getLocation();
6716 return SourceLocation();
6719 static bool shouldWarnIfShadowedDecl(const DiagnosticsEngine &Diags,
6720 const LookupResult &R) {
6721 // Only diagnose if we're shadowing an unambiguous field or variable.
6722 if (R.getResultKind() != LookupResult::Found)
6725 // Return false if warning is ignored.
6726 return !Diags.isIgnored(diag::warn_decl_shadow, R.getNameLoc());
6729 /// \brief Return the declaration shadowed by the given variable \p D, or null
6730 /// if it doesn't shadow any declaration or shadowing warnings are disabled.
6731 NamedDecl *Sema::getShadowedDeclaration(const VarDecl *D,
6732 const LookupResult &R) {
6733 if (!shouldWarnIfShadowedDecl(Diags, R))
6736 // Don't diagnose declarations at file scope.
6737 if (D->hasGlobalStorage())
6740 NamedDecl *ShadowedDecl = R.getFoundDecl();
6741 return isa<VarDecl>(ShadowedDecl) || isa<FieldDecl>(ShadowedDecl)
6746 /// \brief Return the declaration shadowed by the given typedef \p D, or null
6747 /// if it doesn't shadow any declaration or shadowing warnings are disabled.
6748 NamedDecl *Sema::getShadowedDeclaration(const TypedefNameDecl *D,
6749 const LookupResult &R) {
6750 // Don't warn if typedef declaration is part of a class
6751 if (D->getDeclContext()->isRecord())
6754 if (!shouldWarnIfShadowedDecl(Diags, R))
6757 NamedDecl *ShadowedDecl = R.getFoundDecl();
6758 return isa<TypedefNameDecl>(ShadowedDecl) ? ShadowedDecl : nullptr;
6761 /// \brief Diagnose variable or built-in function shadowing. Implements
6764 /// This method is called whenever a VarDecl is added to a "useful"
6767 /// \param ShadowedDecl the declaration that is shadowed by the given variable
6768 /// \param R the lookup of the name
6770 void Sema::CheckShadow(NamedDecl *D, NamedDecl *ShadowedDecl,
6771 const LookupResult &R) {
6772 DeclContext *NewDC = D->getDeclContext();
6774 if (FieldDecl *FD = dyn_cast<FieldDecl>(ShadowedDecl)) {
6775 // Fields are not shadowed by variables in C++ static methods.
6776 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC))
6780 // Fields shadowed by constructor parameters are a special case. Usually
6781 // the constructor initializes the field with the parameter.
6782 if (isa<CXXConstructorDecl>(NewDC))
6783 if (const auto PVD = dyn_cast<ParmVarDecl>(D)) {
6784 // Remember that this was shadowed so we can either warn about its
6785 // modification or its existence depending on warning settings.
6786 ShadowingDecls.insert({PVD->getCanonicalDecl(), FD});
6791 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl))
6792 if (shadowedVar->isExternC()) {
6793 // For shadowing external vars, make sure that we point to the global
6794 // declaration, not a locally scoped extern declaration.
6795 for (auto I : shadowedVar->redecls())
6796 if (I->isFileVarDecl()) {
6802 DeclContext *OldDC = ShadowedDecl->getDeclContext();
6804 unsigned WarningDiag = diag::warn_decl_shadow;
6805 SourceLocation CaptureLoc;
6806 if (isa<VarDecl>(D) && isa<VarDecl>(ShadowedDecl) && NewDC &&
6807 isa<CXXMethodDecl>(NewDC)) {
6808 if (const auto *RD = dyn_cast<CXXRecordDecl>(NewDC->getParent())) {
6809 if (RD->isLambda() && OldDC->Encloses(NewDC->getLexicalParent())) {
6810 if (RD->getLambdaCaptureDefault() == LCD_None) {
6811 // Try to avoid warnings for lambdas with an explicit capture list.
6812 const auto *LSI = cast<LambdaScopeInfo>(getCurFunction());
6813 // Warn only when the lambda captures the shadowed decl explicitly.
6814 CaptureLoc = getCaptureLocation(LSI, cast<VarDecl>(ShadowedDecl));
6815 if (CaptureLoc.isInvalid())
6816 WarningDiag = diag::warn_decl_shadow_uncaptured_local;
6818 // Remember that this was shadowed so we can avoid the warning if the
6819 // shadowed decl isn't captured and the warning settings allow it.
6820 cast<LambdaScopeInfo>(getCurFunction())
6821 ->ShadowingDecls.push_back(
6822 {cast<VarDecl>(D), cast<VarDecl>(ShadowedDecl)});
6829 // Only warn about certain kinds of shadowing for class members.
6830 if (NewDC && NewDC->isRecord()) {
6831 // In particular, don't warn about shadowing non-class members.
6832 if (!OldDC->isRecord())
6835 // TODO: should we warn about static data members shadowing
6836 // static data members from base classes?
6838 // TODO: don't diagnose for inaccessible shadowed members.
6839 // This is hard to do perfectly because we might friend the
6840 // shadowing context, but that's just a false negative.
6844 DeclarationName Name = R.getLookupName();
6846 // Emit warning and note.
6847 if (getSourceManager().isInSystemMacro(R.getNameLoc()))
6849 ShadowedDeclKind Kind = computeShadowedDeclKind(ShadowedDecl, OldDC);
6850 Diag(R.getNameLoc(), WarningDiag) << Name << Kind << OldDC;
6851 if (!CaptureLoc.isInvalid())
6852 Diag(CaptureLoc, diag::note_var_explicitly_captured_here)
6853 << Name << /*explicitly*/ 1;
6854 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6857 /// Diagnose shadowing for variables shadowed in the lambda record \p LambdaRD
6858 /// when these variables are captured by the lambda.
6859 void Sema::DiagnoseShadowingLambdaDecls(const LambdaScopeInfo *LSI) {
6860 for (const auto &Shadow : LSI->ShadowingDecls) {
6861 const VarDecl *ShadowedDecl = Shadow.ShadowedDecl;
6862 // Try to avoid the warning when the shadowed decl isn't captured.
6863 SourceLocation CaptureLoc = getCaptureLocation(LSI, ShadowedDecl);
6864 const DeclContext *OldDC = ShadowedDecl->getDeclContext();
6865 Diag(Shadow.VD->getLocation(), CaptureLoc.isInvalid()
6866 ? diag::warn_decl_shadow_uncaptured_local
6867 : diag::warn_decl_shadow)
6868 << Shadow.VD->getDeclName()
6869 << computeShadowedDeclKind(ShadowedDecl, OldDC) << OldDC;
6870 if (!CaptureLoc.isInvalid())
6871 Diag(CaptureLoc, diag::note_var_explicitly_captured_here)
6872 << Shadow.VD->getDeclName() << /*explicitly*/ 0;
6873 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6877 /// \brief Check -Wshadow without the advantage of a previous lookup.
6878 void Sema::CheckShadow(Scope *S, VarDecl *D) {
6879 if (Diags.isIgnored(diag::warn_decl_shadow, D->getLocation()))
6882 LookupResult R(*this, D->getDeclName(), D->getLocation(),
6883 Sema::LookupOrdinaryName, Sema::ForRedeclaration);
6885 if (NamedDecl *ShadowedDecl = getShadowedDeclaration(D, R))
6886 CheckShadow(D, ShadowedDecl, R);
6889 /// Check if 'E', which is an expression that is about to be modified, refers
6890 /// to a constructor parameter that shadows a field.
6891 void Sema::CheckShadowingDeclModification(Expr *E, SourceLocation Loc) {
6892 // Quickly ignore expressions that can't be shadowing ctor parameters.
6893 if (!getLangOpts().CPlusPlus || ShadowingDecls.empty())
6895 E = E->IgnoreParenImpCasts();
6896 auto *DRE = dyn_cast<DeclRefExpr>(E);
6899 const NamedDecl *D = cast<NamedDecl>(DRE->getDecl()->getCanonicalDecl());
6900 auto I = ShadowingDecls.find(D);
6901 if (I == ShadowingDecls.end())
6903 const NamedDecl *ShadowedDecl = I->second;
6904 const DeclContext *OldDC = ShadowedDecl->getDeclContext();
6905 Diag(Loc, diag::warn_modifying_shadowing_decl) << D << OldDC;
6906 Diag(D->getLocation(), diag::note_var_declared_here) << D;
6907 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6909 // Avoid issuing multiple warnings about the same decl.
6910 ShadowingDecls.erase(I);
6913 /// Check for conflict between this global or extern "C" declaration and
6914 /// previous global or extern "C" declarations. This is only used in C++.
6915 template<typename T>
6916 static bool checkGlobalOrExternCConflict(
6917 Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) {
6918 assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\"");
6919 NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName());
6921 if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) {
6922 // The common case: this global doesn't conflict with any extern "C"
6928 if (!IsGlobal || isIncompleteDeclExternC(S, ND)) {
6929 // Both the old and new declarations have C language linkage. This is a
6932 Previous.addDecl(Prev);
6936 // This is a global, non-extern "C" declaration, and there is a previous
6937 // non-global extern "C" declaration. Diagnose if this is a variable
6939 if (!isa<VarDecl>(ND))
6942 // The declaration is extern "C". Check for any declaration in the
6943 // translation unit which might conflict.
6945 // We have already performed the lookup into the translation unit.
6947 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6949 if (isa<VarDecl>(*I)) {
6955 DeclContext::lookup_result R =
6956 S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName());
6957 for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end();
6959 if (isa<VarDecl>(*I)) {
6963 // FIXME: If we have any other entity with this name in global scope,
6964 // the declaration is ill-formed, but that is a defect: it breaks the
6965 // 'stat' hack, for instance. Only variables can have mangled name
6966 // clashes with extern "C" declarations, so only they deserve a
6975 // Use the first declaration's location to ensure we point at something which
6976 // is lexically inside an extern "C" linkage-spec.
6977 assert(Prev && "should have found a previous declaration to diagnose");
6978 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev))
6979 Prev = FD->getFirstDecl();
6981 Prev = cast<VarDecl>(Prev)->getFirstDecl();
6983 S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict)
6985 S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict)
6990 /// Apply special rules for handling extern "C" declarations. Returns \c true
6991 /// if we have found that this is a redeclaration of some prior entity.
6993 /// Per C++ [dcl.link]p6:
6994 /// Two declarations [for a function or variable] with C language linkage
6995 /// with the same name that appear in different scopes refer to the same
6996 /// [entity]. An entity with C language linkage shall not be declared with
6997 /// the same name as an entity in global scope.
6998 template<typename T>
6999 static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND,
7000 LookupResult &Previous) {
7001 if (!S.getLangOpts().CPlusPlus) {
7002 // In C, when declaring a global variable, look for a corresponding 'extern'
7003 // variable declared in function scope. We don't need this in C++, because
7004 // we find local extern decls in the surrounding file-scope DeclContext.
7005 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
7006 if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) {
7008 Previous.addDecl(Prev);
7015 // A declaration in the translation unit can conflict with an extern "C"
7017 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit())
7018 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous);
7020 // An extern "C" declaration can conflict with a declaration in the
7021 // translation unit or can be a redeclaration of an extern "C" declaration
7022 // in another scope.
7023 if (isIncompleteDeclExternC(S,ND))
7024 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous);
7026 // Neither global nor extern "C": nothing to do.
7030 void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
7031 // If the decl is already known invalid, don't check it.
7032 if (NewVD->isInvalidDecl())
7035 TypeSourceInfo *TInfo = NewVD->getTypeSourceInfo();
7036 QualType T = TInfo->getType();
7038 // Defer checking an 'auto' type until its initializer is attached.
7039 if (T->isUndeducedType())
7042 if (NewVD->hasAttrs())
7043 CheckAlignasUnderalignment(NewVD);
7045 if (T->isObjCObjectType()) {
7046 Diag(NewVD->getLocation(), diag::err_statically_allocated_object)
7047 << FixItHint::CreateInsertion(NewVD->getLocation(), "*");
7048 T = Context.getObjCObjectPointerType(T);
7052 // Emit an error if an address space was applied to decl with local storage.
7053 // This includes arrays of objects with address space qualifiers, but not
7054 // automatic variables that point to other address spaces.
7055 // ISO/IEC TR 18037 S5.1.2
7056 if (!getLangOpts().OpenCL
7057 && NewVD->hasLocalStorage() && T.getAddressSpace() != 0) {
7058 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl);
7059 NewVD->setInvalidDecl();
7063 // OpenCL v1.2 s6.8 - The static qualifier is valid only in program
7065 if (getLangOpts().OpenCLVersion == 120 &&
7066 !getOpenCLOptions().isEnabled("cl_clang_storage_class_specifiers") &&
7067 NewVD->isStaticLocal()) {
7068 Diag(NewVD->getLocation(), diag::err_static_function_scope);
7069 NewVD->setInvalidDecl();
7073 if (getLangOpts().OpenCL) {
7074 // OpenCL v2.0 s6.12.5 - The __block storage type is not supported.
7075 if (NewVD->hasAttr<BlocksAttr>()) {
7076 Diag(NewVD->getLocation(), diag::err_opencl_block_storage_type);
7080 if (T->isBlockPointerType()) {
7081 // OpenCL v2.0 s6.12.5 - Any block declaration must be const qualified and
7082 // can't use 'extern' storage class.
7083 if (!T.isConstQualified()) {
7084 Diag(NewVD->getLocation(), diag::err_opencl_invalid_block_declaration)
7086 NewVD->setInvalidDecl();
7089 if (NewVD->hasExternalStorage()) {
7090 Diag(NewVD->getLocation(), diag::err_opencl_extern_block_declaration);
7091 NewVD->setInvalidDecl();
7095 // OpenCL v1.2 s6.5 - All program scope variables must be declared in the
7096 // __constant address space.
7097 // OpenCL v2.0 s6.5.1 - Variables defined at program scope and static
7098 // variables inside a function can also be declared in the global
7100 if (NewVD->isFileVarDecl() || NewVD->isStaticLocal() ||
7101 NewVD->hasExternalStorage()) {
7102 if (!T->isSamplerT() &&
7103 !(T.getAddressSpace() == LangAS::opencl_constant ||
7104 (T.getAddressSpace() == LangAS::opencl_global &&
7105 getLangOpts().OpenCLVersion == 200))) {
7106 int Scope = NewVD->isStaticLocal() | NewVD->hasExternalStorage() << 1;
7107 if (getLangOpts().OpenCLVersion == 200)
7108 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
7109 << Scope << "global or constant";
7111 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
7112 << Scope << "constant";
7113 NewVD->setInvalidDecl();
7117 if (T.getAddressSpace() == LangAS::opencl_global) {
7118 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
7119 << 1 /*is any function*/ << "global";
7120 NewVD->setInvalidDecl();
7123 // OpenCL v1.1 s6.5.2 and s6.5.3 no local or constant variables
7125 if (T.getAddressSpace() == LangAS::opencl_constant ||
7126 T.getAddressSpace() == LangAS::opencl_local) {
7127 FunctionDecl *FD = getCurFunctionDecl();
7128 if (FD && !FD->hasAttr<OpenCLKernelAttr>()) {
7129 if (T.getAddressSpace() == LangAS::opencl_constant)
7130 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
7131 << 0 /*non-kernel only*/ << "constant";
7133 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
7134 << 0 /*non-kernel only*/ << "local";
7135 NewVD->setInvalidDecl();
7142 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()
7143 && !NewVD->hasAttr<BlocksAttr>()) {
7144 if (getLangOpts().getGC() != LangOptions::NonGC)
7145 Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local);
7147 assert(!getLangOpts().ObjCAutoRefCount);
7148 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
7152 bool isVM = T->isVariablyModifiedType();
7153 if (isVM || NewVD->hasAttr<CleanupAttr>() ||
7154 NewVD->hasAttr<BlocksAttr>())
7155 getCurFunction()->setHasBranchProtectedScope();
7157 if ((isVM && NewVD->hasLinkage()) ||
7158 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) {
7159 bool SizeIsNegative;
7160 llvm::APSInt Oversized;
7161 TypeSourceInfo *FixedTInfo =
7162 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
7163 SizeIsNegative, Oversized);
7164 if (!FixedTInfo && T->isVariableArrayType()) {
7165 const VariableArrayType *VAT = Context.getAsVariableArrayType(T);
7166 // FIXME: This won't give the correct result for
7168 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange();
7170 if (NewVD->isFileVarDecl())
7171 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope)
7173 else if (NewVD->isStaticLocal())
7174 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage)
7177 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage)
7179 NewVD->setInvalidDecl();
7184 if (NewVD->isFileVarDecl())
7185 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope);
7187 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage);
7188 NewVD->setInvalidDecl();
7192 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size);
7193 NewVD->setType(FixedTInfo->getType());
7194 NewVD->setTypeSourceInfo(FixedTInfo);
7197 if (T->isVoidType()) {
7198 // C++98 [dcl.stc]p5: The extern specifier can be applied only to the names
7199 // of objects and functions.
7200 if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) {
7201 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type)
7203 NewVD->setInvalidDecl();
7208 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) {
7209 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal);
7210 NewVD->setInvalidDecl();
7214 if (isVM && NewVD->hasAttr<BlocksAttr>()) {
7215 Diag(NewVD->getLocation(), diag::err_block_on_vm);
7216 NewVD->setInvalidDecl();
7220 if (NewVD->isConstexpr() && !T->isDependentType() &&
7221 RequireLiteralType(NewVD->getLocation(), T,
7222 diag::err_constexpr_var_non_literal)) {
7223 NewVD->setInvalidDecl();
7228 /// \brief Perform semantic checking on a newly-created variable
7231 /// This routine performs all of the type-checking required for a
7232 /// variable declaration once it has been built. It is used both to
7233 /// check variables after they have been parsed and their declarators
7234 /// have been translated into a declaration, and to check variables
7235 /// that have been instantiated from a template.
7237 /// Sets NewVD->isInvalidDecl() if an error was encountered.
7239 /// Returns true if the variable declaration is a redeclaration.
7240 bool Sema::CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous) {
7241 CheckVariableDeclarationType(NewVD);
7243 // If the decl is already known invalid, don't check it.
7244 if (NewVD->isInvalidDecl())
7247 // If we did not find anything by this name, look for a non-visible
7248 // extern "C" declaration with the same name.
7249 if (Previous.empty() &&
7250 checkForConflictWithNonVisibleExternC(*this, NewVD, Previous))
7251 Previous.setShadowed();
7253 if (!Previous.empty()) {
7254 MergeVarDecl(NewVD, Previous);
7261 struct FindOverriddenMethod {
7263 CXXMethodDecl *Method;
7265 /// Member lookup function that determines whether a given C++
7266 /// method overrides a method in a base class, to be used with
7267 /// CXXRecordDecl::lookupInBases().
7268 bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
7269 RecordDecl *BaseRecord =
7270 Specifier->getType()->getAs<RecordType>()->getDecl();
7272 DeclarationName Name = Method->getDeclName();
7274 // FIXME: Do we care about other names here too?
7275 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7276 // We really want to find the base class destructor here.
7277 QualType T = S->Context.getTypeDeclType(BaseRecord);
7278 CanQualType CT = S->Context.getCanonicalType(T);
7280 Name = S->Context.DeclarationNames.getCXXDestructorName(CT);
7283 for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
7284 Path.Decls = Path.Decls.slice(1)) {
7285 NamedDecl *D = Path.Decls.front();
7286 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
7287 if (MD->isVirtual() && !S->IsOverload(Method, MD, false))
7296 enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted };
7297 } // end anonymous namespace
7299 /// \brief Report an error regarding overriding, along with any relevant
7300 /// overriden methods.
7302 /// \param DiagID the primary error to report.
7303 /// \param MD the overriding method.
7304 /// \param OEK which overrides to include as notes.
7305 static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD,
7306 OverrideErrorKind OEK = OEK_All) {
7307 S.Diag(MD->getLocation(), DiagID) << MD->getDeclName();
7308 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
7309 E = MD->end_overridden_methods();
7311 // This check (& the OEK parameter) could be replaced by a predicate, but
7312 // without lambdas that would be overkill. This is still nicer than writing
7313 // out the diag loop 3 times.
7314 if ((OEK == OEK_All) ||
7315 (OEK == OEK_NonDeleted && !(*I)->isDeleted()) ||
7316 (OEK == OEK_Deleted && (*I)->isDeleted()))
7317 S.Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
7321 /// AddOverriddenMethods - See if a method overrides any in the base classes,
7322 /// and if so, check that it's a valid override and remember it.
7323 bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) {
7324 // Look for methods in base classes that this method might override.
7326 FindOverriddenMethod FOM;
7329 bool hasDeletedOverridenMethods = false;
7330 bool hasNonDeletedOverridenMethods = false;
7331 bool AddedAny = false;
7332 if (DC->lookupInBases(FOM, Paths)) {
7333 for (auto *I : Paths.found_decls()) {
7334 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(I)) {
7335 MD->addOverriddenMethod(OldMD->getCanonicalDecl());
7336 if (!CheckOverridingFunctionReturnType(MD, OldMD) &&
7337 !CheckOverridingFunctionAttributes(MD, OldMD) &&
7338 !CheckOverridingFunctionExceptionSpec(MD, OldMD) &&
7339 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) {
7340 hasDeletedOverridenMethods |= OldMD->isDeleted();
7341 hasNonDeletedOverridenMethods |= !OldMD->isDeleted();
7348 if (hasDeletedOverridenMethods && !MD->isDeleted()) {
7349 ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted);
7351 if (hasNonDeletedOverridenMethods && MD->isDeleted()) {
7352 ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted);
7359 // Struct for holding all of the extra arguments needed by
7360 // DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator.
7361 struct ActOnFDArgs {
7364 MultiTemplateParamsArg TemplateParamLists;
7367 } // end anonymous namespace
7371 // Callback to only accept typo corrections that have a non-zero edit distance.
7372 // Also only accept corrections that have the same parent decl.
7373 class DifferentNameValidatorCCC : public CorrectionCandidateCallback {
7375 DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD,
7376 CXXRecordDecl *Parent)
7377 : Context(Context), OriginalFD(TypoFD),
7378 ExpectedParent(Parent ? Parent->getCanonicalDecl() : nullptr) {}
7380 bool ValidateCandidate(const TypoCorrection &candidate) override {
7381 if (candidate.getEditDistance() == 0)
7384 SmallVector<unsigned, 1> MismatchedParams;
7385 for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(),
7386 CDeclEnd = candidate.end();
7387 CDecl != CDeclEnd; ++CDecl) {
7388 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7390 if (FD && !FD->hasBody() &&
7391 hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) {
7392 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
7393 CXXRecordDecl *Parent = MD->getParent();
7394 if (Parent && Parent->getCanonicalDecl() == ExpectedParent)
7396 } else if (!ExpectedParent) {
7406 ASTContext &Context;
7407 FunctionDecl *OriginalFD;
7408 CXXRecordDecl *ExpectedParent;
7411 } // end anonymous namespace
7413 /// \brief Generate diagnostics for an invalid function redeclaration.
7415 /// This routine handles generating the diagnostic messages for an invalid
7416 /// function redeclaration, including finding possible similar declarations
7417 /// or performing typo correction if there are no previous declarations with
7420 /// Returns a NamedDecl iff typo correction was performed and substituting in
7421 /// the new declaration name does not cause new errors.
7422 static NamedDecl *DiagnoseInvalidRedeclaration(
7423 Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD,
7424 ActOnFDArgs &ExtraArgs, bool IsLocalFriend, Scope *S) {
7425 DeclarationName Name = NewFD->getDeclName();
7426 DeclContext *NewDC = NewFD->getDeclContext();
7427 SmallVector<unsigned, 1> MismatchedParams;
7428 SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches;
7429 TypoCorrection Correction;
7430 bool IsDefinition = ExtraArgs.D.isFunctionDefinition();
7431 unsigned DiagMsg = IsLocalFriend ? diag::err_no_matching_local_friend
7432 : diag::err_member_decl_does_not_match;
7433 LookupResult Prev(SemaRef, Name, NewFD->getLocation(),
7434 IsLocalFriend ? Sema::LookupLocalFriendName
7435 : Sema::LookupOrdinaryName,
7436 Sema::ForRedeclaration);
7438 NewFD->setInvalidDecl();
7440 SemaRef.LookupName(Prev, S);
7442 SemaRef.LookupQualifiedName(Prev, NewDC);
7443 assert(!Prev.isAmbiguous() &&
7444 "Cannot have an ambiguity in previous-declaration lookup");
7445 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
7446 if (!Prev.empty()) {
7447 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end();
7448 Func != FuncEnd; ++Func) {
7449 FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func);
7451 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7452 // Add 1 to the index so that 0 can mean the mismatch didn't
7453 // involve a parameter
7455 MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1;
7456 NearMatches.push_back(std::make_pair(FD, ParamNum));
7459 // If the qualified name lookup yielded nothing, try typo correction
7460 } else if ((Correction = SemaRef.CorrectTypo(
7461 Prev.getLookupNameInfo(), Prev.getLookupKind(), S,
7462 &ExtraArgs.D.getCXXScopeSpec(),
7463 llvm::make_unique<DifferentNameValidatorCCC>(
7464 SemaRef.Context, NewFD, MD ? MD->getParent() : nullptr),
7465 Sema::CTK_ErrorRecovery, IsLocalFriend ? nullptr : NewDC))) {
7466 // Set up everything for the call to ActOnFunctionDeclarator
7467 ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(),
7468 ExtraArgs.D.getIdentifierLoc());
7470 Previous.setLookupName(Correction.getCorrection());
7471 for (TypoCorrection::decl_iterator CDecl = Correction.begin(),
7472 CDeclEnd = Correction.end();
7473 CDecl != CDeclEnd; ++CDecl) {
7474 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7475 if (FD && !FD->hasBody() &&
7476 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7477 Previous.addDecl(FD);
7480 bool wasRedeclaration = ExtraArgs.D.isRedeclaration();
7483 // Retry building the function declaration with the new previous
7484 // declarations, and with errors suppressed.
7487 Sema::SFINAETrap Trap(SemaRef);
7489 // TODO: Refactor ActOnFunctionDeclarator so that we can call only the
7490 // pieces need to verify the typo-corrected C++ declaration and hopefully
7491 // eliminate the need for the parameter pack ExtraArgs.
7492 Result = SemaRef.ActOnFunctionDeclarator(
7493 ExtraArgs.S, ExtraArgs.D,
7494 Correction.getCorrectionDecl()->getDeclContext(),
7495 NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists,
7496 ExtraArgs.AddToScope);
7498 if (Trap.hasErrorOccurred())
7503 // Determine which correction we picked.
7504 Decl *Canonical = Result->getCanonicalDecl();
7505 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
7507 if ((*I)->getCanonicalDecl() == Canonical)
7508 Correction.setCorrectionDecl(*I);
7510 SemaRef.diagnoseTypo(
7512 SemaRef.PDiag(IsLocalFriend
7513 ? diag::err_no_matching_local_friend_suggest
7514 : diag::err_member_decl_does_not_match_suggest)
7515 << Name << NewDC << IsDefinition);
7519 // Pretend the typo correction never occurred
7520 ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(),
7521 ExtraArgs.D.getIdentifierLoc());
7522 ExtraArgs.D.setRedeclaration(wasRedeclaration);
7524 Previous.setLookupName(Name);
7527 SemaRef.Diag(NewFD->getLocation(), DiagMsg)
7528 << Name << NewDC << IsDefinition << NewFD->getLocation();
7530 bool NewFDisConst = false;
7531 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD))
7532 NewFDisConst = NewMD->isConst();
7534 for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator
7535 NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end();
7536 NearMatch != NearMatchEnd; ++NearMatch) {
7537 FunctionDecl *FD = NearMatch->first;
7538 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
7539 bool FDisConst = MD && MD->isConst();
7540 bool IsMember = MD || !IsLocalFriend;
7542 // FIXME: These notes are poorly worded for the local friend case.
7543 if (unsigned Idx = NearMatch->second) {
7544 ParmVarDecl *FDParam = FD->getParamDecl(Idx-1);
7545 SourceLocation Loc = FDParam->getTypeSpecStartLoc();
7546 if (Loc.isInvalid()) Loc = FD->getLocation();
7547 SemaRef.Diag(Loc, IsMember ? diag::note_member_def_close_param_match
7548 : diag::note_local_decl_close_param_match)
7549 << Idx << FDParam->getType()
7550 << NewFD->getParamDecl(Idx - 1)->getType();
7551 } else if (FDisConst != NewFDisConst) {
7552 SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match)
7553 << NewFDisConst << FD->getSourceRange().getEnd();
7555 SemaRef.Diag(FD->getLocation(),
7556 IsMember ? diag::note_member_def_close_match
7557 : diag::note_local_decl_close_match);
7562 static StorageClass getFunctionStorageClass(Sema &SemaRef, Declarator &D) {
7563 switch (D.getDeclSpec().getStorageClassSpec()) {
7564 default: llvm_unreachable("Unknown storage class!");
7565 case DeclSpec::SCS_auto:
7566 case DeclSpec::SCS_register:
7567 case DeclSpec::SCS_mutable:
7568 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7569 diag::err_typecheck_sclass_func);
7570 D.getMutableDeclSpec().ClearStorageClassSpecs();
7573 case DeclSpec::SCS_unspecified: break;
7574 case DeclSpec::SCS_extern:
7575 if (D.getDeclSpec().isExternInLinkageSpec())
7578 case DeclSpec::SCS_static: {
7579 if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) {
7581 // The declaration of an identifier for a function that has
7582 // block scope shall have no explicit storage-class specifier
7583 // other than extern
7584 // See also (C++ [dcl.stc]p4).
7585 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7586 diag::err_static_block_func);
7591 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
7594 // No explicit storage class has already been returned
7598 static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
7599 DeclContext *DC, QualType &R,
7600 TypeSourceInfo *TInfo,
7602 bool &IsVirtualOkay) {
7603 DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D);
7604 DeclarationName Name = NameInfo.getName();
7606 FunctionDecl *NewFD = nullptr;
7607 bool isInline = D.getDeclSpec().isInlineSpecified();
7609 if (!SemaRef.getLangOpts().CPlusPlus) {
7610 // Determine whether the function was written with a
7611 // prototype. This true when:
7612 // - there is a prototype in the declarator, or
7613 // - the type R of the function is some kind of typedef or other non-
7614 // attributed reference to a type name (which eventually refers to a
7617 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) ||
7618 (!R->getAsAdjusted<FunctionType>() && R->isFunctionProtoType());
7620 NewFD = FunctionDecl::Create(SemaRef.Context, DC,
7621 D.getLocStart(), NameInfo, R,
7622 TInfo, SC, isInline,
7623 HasPrototype, false);
7624 if (D.isInvalidType())
7625 NewFD->setInvalidDecl();
7630 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
7631 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
7633 // Check that the return type is not an abstract class type.
7634 // For record types, this is done by the AbstractClassUsageDiagnoser once
7635 // the class has been completely parsed.
7636 if (!DC->isRecord() &&
7637 SemaRef.RequireNonAbstractType(
7638 D.getIdentifierLoc(), R->getAs<FunctionType>()->getReturnType(),
7639 diag::err_abstract_type_in_decl, SemaRef.AbstractReturnType))
7642 if (Name.getNameKind() == DeclarationName::CXXConstructorName) {
7643 // This is a C++ constructor declaration.
7644 assert(DC->isRecord() &&
7645 "Constructors can only be declared in a member context");
7647 R = SemaRef.CheckConstructorDeclarator(D, R, SC);
7648 return CXXConstructorDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7649 D.getLocStart(), NameInfo,
7650 R, TInfo, isExplicit, isInline,
7651 /*isImplicitlyDeclared=*/false,
7654 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7655 // This is a C++ destructor declaration.
7656 if (DC->isRecord()) {
7657 R = SemaRef.CheckDestructorDeclarator(D, R, SC);
7658 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
7659 CXXDestructorDecl *NewDD = CXXDestructorDecl::Create(
7660 SemaRef.Context, Record,
7662 NameInfo, R, TInfo, isInline,
7663 /*isImplicitlyDeclared=*/false);
7665 // If the class is complete, then we now create the implicit exception
7666 // specification. If the class is incomplete or dependent, we can't do
7668 if (SemaRef.getLangOpts().CPlusPlus11 && !Record->isDependentType() &&
7669 Record->getDefinition() && !Record->isBeingDefined() &&
7670 R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) {
7671 SemaRef.AdjustDestructorExceptionSpec(Record, NewDD);
7674 IsVirtualOkay = true;
7678 SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member);
7681 // Create a FunctionDecl to satisfy the function definition parsing
7683 return FunctionDecl::Create(SemaRef.Context, DC,
7685 D.getIdentifierLoc(), Name, R, TInfo,
7687 /*hasPrototype=*/true, isConstexpr);
7690 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
7691 if (!DC->isRecord()) {
7692 SemaRef.Diag(D.getIdentifierLoc(),
7693 diag::err_conv_function_not_member);
7697 SemaRef.CheckConversionDeclarator(D, R, SC);
7698 IsVirtualOkay = true;
7699 return CXXConversionDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7700 D.getLocStart(), NameInfo,
7701 R, TInfo, isInline, isExplicit,
7702 isConstexpr, SourceLocation());
7704 } else if (Name.getNameKind() == DeclarationName::CXXDeductionGuideName) {
7705 SemaRef.CheckDeductionGuideDeclarator(D, R, SC);
7707 return CXXDeductionGuideDecl::Create(SemaRef.Context, DC, D.getLocStart(),
7708 isExplicit, NameInfo, R, TInfo,
7710 } else if (DC->isRecord()) {
7711 // If the name of the function is the same as the name of the record,
7712 // then this must be an invalid constructor that has a return type.
7713 // (The parser checks for a return type and makes the declarator a
7714 // constructor if it has no return type).
7715 if (Name.getAsIdentifierInfo() &&
7716 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){
7717 SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type)
7718 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
7719 << SourceRange(D.getIdentifierLoc());
7723 // This is a C++ method declaration.
7724 CXXMethodDecl *Ret = CXXMethodDecl::Create(SemaRef.Context,
7725 cast<CXXRecordDecl>(DC),
7726 D.getLocStart(), NameInfo, R,
7727 TInfo, SC, isInline,
7728 isConstexpr, SourceLocation());
7729 IsVirtualOkay = !Ret->isStatic();
7733 SemaRef.getLangOpts().CPlusPlus && D.getDeclSpec().isFriendSpecified();
7734 if (!isFriend && SemaRef.CurContext->isRecord())
7737 // Determine whether the function was written with a
7738 // prototype. This true when:
7739 // - we're in C++ (where every function has a prototype),
7740 return FunctionDecl::Create(SemaRef.Context, DC,
7742 NameInfo, R, TInfo, SC, isInline,
7743 true/*HasPrototype*/, isConstexpr);
7747 enum OpenCLParamType {
7751 InvalidAddrSpacePtrKernelParam,
7756 static OpenCLParamType getOpenCLKernelParameterType(Sema &S, QualType PT) {
7757 if (PT->isPointerType()) {
7758 QualType PointeeType = PT->getPointeeType();
7759 if (PointeeType->isPointerType())
7760 return PtrPtrKernelParam;
7761 if (PointeeType.getAddressSpace() == LangAS::opencl_generic ||
7762 PointeeType.getAddressSpace() == 0)
7763 return InvalidAddrSpacePtrKernelParam;
7764 return PtrKernelParam;
7767 // TODO: Forbid the other integer types (size_t, ptrdiff_t...) when they can
7768 // be used as builtin types.
7770 if (PT->isImageType())
7771 return PtrKernelParam;
7773 if (PT->isBooleanType())
7774 return InvalidKernelParam;
7777 return InvalidKernelParam;
7779 // OpenCL extension spec v1.2 s9.5:
7780 // This extension adds support for half scalar and vector types as built-in
7781 // types that can be used for arithmetic operations, conversions etc.
7782 if (!S.getOpenCLOptions().isEnabled("cl_khr_fp16") && PT->isHalfType())
7783 return InvalidKernelParam;
7785 if (PT->isRecordType())
7786 return RecordKernelParam;
7788 return ValidKernelParam;
7791 static void checkIsValidOpenCLKernelParameter(
7795 llvm::SmallPtrSetImpl<const Type *> &ValidTypes) {
7796 QualType PT = Param->getType();
7798 // Cache the valid types we encounter to avoid rechecking structs that are
7800 if (ValidTypes.count(PT.getTypePtr()))
7803 switch (getOpenCLKernelParameterType(S, PT)) {
7804 case PtrPtrKernelParam:
7805 // OpenCL v1.2 s6.9.a:
7806 // A kernel function argument cannot be declared as a
7807 // pointer to a pointer type.
7808 S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param);
7812 case InvalidAddrSpacePtrKernelParam:
7813 // OpenCL v1.0 s6.5:
7814 // __kernel function arguments declared to be a pointer of a type can point
7815 // to one of the following address spaces only : __global, __local or
7817 S.Diag(Param->getLocation(), diag::err_kernel_arg_address_space);
7821 // OpenCL v1.2 s6.9.k:
7822 // Arguments to kernel functions in a program cannot be declared with the
7823 // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and
7824 // uintptr_t or a struct and/or union that contain fields declared to be
7825 // one of these built-in scalar types.
7827 case InvalidKernelParam:
7828 // OpenCL v1.2 s6.8 n:
7829 // A kernel function argument cannot be declared
7831 // Do not diagnose half type since it is diagnosed as invalid argument
7832 // type for any function elsewhere.
7833 if (!PT->isHalfType())
7834 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7838 case PtrKernelParam:
7839 case ValidKernelParam:
7840 ValidTypes.insert(PT.getTypePtr());
7843 case RecordKernelParam:
7847 // Track nested structs we will inspect
7848 SmallVector<const Decl *, 4> VisitStack;
7850 // Track where we are in the nested structs. Items will migrate from
7851 // VisitStack to HistoryStack as we do the DFS for bad field.
7852 SmallVector<const FieldDecl *, 4> HistoryStack;
7853 HistoryStack.push_back(nullptr);
7855 const RecordDecl *PD = PT->castAs<RecordType>()->getDecl();
7856 VisitStack.push_back(PD);
7858 assert(VisitStack.back() && "First decl null?");
7861 const Decl *Next = VisitStack.pop_back_val();
7863 assert(!HistoryStack.empty());
7864 // Found a marker, we have gone up a level
7865 if (const FieldDecl *Hist = HistoryStack.pop_back_val())
7866 ValidTypes.insert(Hist->getType().getTypePtr());
7871 // Adds everything except the original parameter declaration (which is not a
7872 // field itself) to the history stack.
7873 const RecordDecl *RD;
7874 if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) {
7875 HistoryStack.push_back(Field);
7876 RD = Field->getType()->castAs<RecordType>()->getDecl();
7878 RD = cast<RecordDecl>(Next);
7881 // Add a null marker so we know when we've gone back up a level
7882 VisitStack.push_back(nullptr);
7884 for (const auto *FD : RD->fields()) {
7885 QualType QT = FD->getType();
7887 if (ValidTypes.count(QT.getTypePtr()))
7890 OpenCLParamType ParamType = getOpenCLKernelParameterType(S, QT);
7891 if (ParamType == ValidKernelParam)
7894 if (ParamType == RecordKernelParam) {
7895 VisitStack.push_back(FD);
7899 // OpenCL v1.2 s6.9.p:
7900 // Arguments to kernel functions that are declared to be a struct or union
7901 // do not allow OpenCL objects to be passed as elements of the struct or
7903 if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam ||
7904 ParamType == InvalidAddrSpacePtrKernelParam) {
7905 S.Diag(Param->getLocation(),
7906 diag::err_record_with_pointers_kernel_param)
7907 << PT->isUnionType()
7910 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7913 S.Diag(PD->getLocation(), diag::note_within_field_of_type)
7914 << PD->getDeclName();
7916 // We have an error, now let's go back up through history and show where
7917 // the offending field came from
7918 for (ArrayRef<const FieldDecl *>::const_iterator
7919 I = HistoryStack.begin() + 1,
7920 E = HistoryStack.end();
7922 const FieldDecl *OuterField = *I;
7923 S.Diag(OuterField->getLocation(), diag::note_within_field_of_type)
7924 << OuterField->getType();
7927 S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here)
7928 << QT->isPointerType()
7933 } while (!VisitStack.empty());
7936 /// Find the DeclContext in which a tag is implicitly declared if we see an
7937 /// elaborated type specifier in the specified context, and lookup finds
7939 static DeclContext *getTagInjectionContext(DeclContext *DC) {
7940 while (!DC->isFileContext() && !DC->isFunctionOrMethod())
7941 DC = DC->getParent();
7945 /// Find the Scope in which a tag is implicitly declared if we see an
7946 /// elaborated type specifier in the specified context, and lookup finds
7948 static Scope *getTagInjectionScope(Scope *S, const LangOptions &LangOpts) {
7949 while (S->isClassScope() ||
7950 (LangOpts.CPlusPlus &&
7951 S->isFunctionPrototypeScope()) ||
7952 ((S->getFlags() & Scope::DeclScope) == 0) ||
7953 (S->getEntity() && S->getEntity()->isTransparentContext()))
7959 Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
7960 TypeSourceInfo *TInfo, LookupResult &Previous,
7961 MultiTemplateParamsArg TemplateParamLists,
7963 QualType R = TInfo->getType();
7965 assert(R.getTypePtr()->isFunctionType());
7967 // TODO: consider using NameInfo for diagnostic.
7968 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
7969 DeclarationName Name = NameInfo.getName();
7970 StorageClass SC = getFunctionStorageClass(*this, D);
7972 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
7973 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
7974 diag::err_invalid_thread)
7975 << DeclSpec::getSpecifierName(TSCS);
7977 if (D.isFirstDeclarationOfMember())
7978 adjustMemberFunctionCC(R, D.isStaticMember(), D.isCtorOrDtor(),
7979 D.getIdentifierLoc());
7981 bool isFriend = false;
7982 FunctionTemplateDecl *FunctionTemplate = nullptr;
7983 bool isMemberSpecialization = false;
7984 bool isFunctionTemplateSpecialization = false;
7986 bool isDependentClassScopeExplicitSpecialization = false;
7987 bool HasExplicitTemplateArgs = false;
7988 TemplateArgumentListInfo TemplateArgs;
7990 bool isVirtualOkay = false;
7992 DeclContext *OriginalDC = DC;
7993 bool IsLocalExternDecl = adjustContextForLocalExternDecl(DC);
7995 FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC,
7997 if (!NewFD) return nullptr;
7999 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer())
8000 NewFD->setTopLevelDeclInObjCContainer();
8002 // Set the lexical context. If this is a function-scope declaration, or has a
8003 // C++ scope specifier, or is the object of a friend declaration, the lexical
8004 // context will be different from the semantic context.
8005 NewFD->setLexicalDeclContext(CurContext);
8007 if (IsLocalExternDecl)
8008 NewFD->setLocalExternDecl();
8010 if (getLangOpts().CPlusPlus) {
8011 bool isInline = D.getDeclSpec().isInlineSpecified();
8012 bool isVirtual = D.getDeclSpec().isVirtualSpecified();
8013 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
8014 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
8015 bool isConcept = D.getDeclSpec().isConceptSpecified();
8016 isFriend = D.getDeclSpec().isFriendSpecified();
8017 if (isFriend && !isInline && D.isFunctionDefinition()) {
8018 // C++ [class.friend]p5
8019 // A function can be defined in a friend declaration of a
8020 // class . . . . Such a function is implicitly inline.
8021 NewFD->setImplicitlyInline();
8024 // If this is a method defined in an __interface, and is not a constructor
8025 // or an overloaded operator, then set the pure flag (isVirtual will already
8027 if (const CXXRecordDecl *Parent =
8028 dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) {
8029 if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided())
8030 NewFD->setPure(true);
8032 // C++ [class.union]p2
8033 // A union can have member functions, but not virtual functions.
8034 if (isVirtual && Parent->isUnion())
8035 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_in_union);
8038 SetNestedNameSpecifier(NewFD, D);
8039 isMemberSpecialization = false;
8040 isFunctionTemplateSpecialization = false;
8041 if (D.isInvalidType())
8042 NewFD->setInvalidDecl();
8044 // Match up the template parameter lists with the scope specifier, then
8045 // determine whether we have a template or a template specialization.
8046 bool Invalid = false;
8047 if (TemplateParameterList *TemplateParams =
8048 MatchTemplateParametersToScopeSpecifier(
8049 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
8050 D.getCXXScopeSpec(),
8051 D.getName().getKind() == UnqualifiedId::IK_TemplateId
8052 ? D.getName().TemplateId
8054 TemplateParamLists, isFriend, isMemberSpecialization,
8056 if (TemplateParams->size() > 0) {
8057 // This is a function template
8059 // Check that we can declare a template here.
8060 if (CheckTemplateDeclScope(S, TemplateParams))
8061 NewFD->setInvalidDecl();
8063 // A destructor cannot be a template.
8064 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
8065 Diag(NewFD->getLocation(), diag::err_destructor_template);
8066 NewFD->setInvalidDecl();
8069 // If we're adding a template to a dependent context, we may need to
8070 // rebuilding some of the types used within the template parameter list,
8071 // now that we know what the current instantiation is.
8072 if (DC->isDependentContext()) {
8073 ContextRAII SavedContext(*this, DC);
8074 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
8078 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC,
8079 NewFD->getLocation(),
8080 Name, TemplateParams,
8082 FunctionTemplate->setLexicalDeclContext(CurContext);
8083 NewFD->setDescribedFunctionTemplate(FunctionTemplate);
8085 // For source fidelity, store the other template param lists.
8086 if (TemplateParamLists.size() > 1) {
8087 NewFD->setTemplateParameterListsInfo(Context,
8088 TemplateParamLists.drop_back(1));
8091 // This is a function template specialization.
8092 isFunctionTemplateSpecialization = true;
8093 // For source fidelity, store all the template param lists.
8094 if (TemplateParamLists.size() > 0)
8095 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
8097 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);".
8099 // We want to remove the "template<>", found here.
8100 SourceRange RemoveRange = TemplateParams->getSourceRange();
8102 // If we remove the template<> and the name is not a
8103 // template-id, we're actually silently creating a problem:
8104 // the friend declaration will refer to an untemplated decl,
8105 // and clearly the user wants a template specialization. So
8106 // we need to insert '<>' after the name.
8107 SourceLocation InsertLoc;
8108 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
8109 InsertLoc = D.getName().getSourceRange().getEnd();
8110 InsertLoc = getLocForEndOfToken(InsertLoc);
8113 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend)
8114 << Name << RemoveRange
8115 << FixItHint::CreateRemoval(RemoveRange)
8116 << FixItHint::CreateInsertion(InsertLoc, "<>");
8121 // All template param lists were matched against the scope specifier:
8122 // this is NOT (an explicit specialization of) a template.
8123 if (TemplateParamLists.size() > 0)
8124 // For source fidelity, store all the template param lists.
8125 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
8129 NewFD->setInvalidDecl();
8130 if (FunctionTemplate)
8131 FunctionTemplate->setInvalidDecl();
8134 // C++ [dcl.fct.spec]p5:
8135 // The virtual specifier shall only be used in declarations of
8136 // nonstatic class member functions that appear within a
8137 // member-specification of a class declaration; see 10.3.
8139 if (isVirtual && !NewFD->isInvalidDecl()) {
8140 if (!isVirtualOkay) {
8141 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8142 diag::err_virtual_non_function);
8143 } else if (!CurContext->isRecord()) {
8144 // 'virtual' was specified outside of the class.
8145 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8146 diag::err_virtual_out_of_class)
8147 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
8148 } else if (NewFD->getDescribedFunctionTemplate()) {
8149 // C++ [temp.mem]p3:
8150 // A member function template shall not be virtual.
8151 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8152 diag::err_virtual_member_function_template)
8153 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
8155 // Okay: Add virtual to the method.
8156 NewFD->setVirtualAsWritten(true);
8159 if (getLangOpts().CPlusPlus14 &&
8160 NewFD->getReturnType()->isUndeducedType())
8161 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual);
8164 if (getLangOpts().CPlusPlus14 &&
8165 (NewFD->isDependentContext() ||
8166 (isFriend && CurContext->isDependentContext())) &&
8167 NewFD->getReturnType()->isUndeducedType()) {
8168 // If the function template is referenced directly (for instance, as a
8169 // member of the current instantiation), pretend it has a dependent type.
8170 // This is not really justified by the standard, but is the only sane
8172 // FIXME: For a friend function, we have not marked the function as being
8173 // a friend yet, so 'isDependentContext' on the FD doesn't work.
8174 const FunctionProtoType *FPT =
8175 NewFD->getType()->castAs<FunctionProtoType>();
8177 SubstAutoType(FPT->getReturnType(), Context.DependentTy);
8178 NewFD->setType(Context.getFunctionType(Result, FPT->getParamTypes(),
8179 FPT->getExtProtoInfo()));
8182 // C++ [dcl.fct.spec]p3:
8183 // The inline specifier shall not appear on a block scope function
8185 if (isInline && !NewFD->isInvalidDecl()) {
8186 if (CurContext->isFunctionOrMethod()) {
8187 // 'inline' is not allowed on block scope function declaration.
8188 Diag(D.getDeclSpec().getInlineSpecLoc(),
8189 diag::err_inline_declaration_block_scope) << Name
8190 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
8194 // C++ [dcl.fct.spec]p6:
8195 // The explicit specifier shall be used only in the declaration of a
8196 // constructor or conversion function within its class definition;
8197 // see 12.3.1 and 12.3.2.
8198 if (isExplicit && !NewFD->isInvalidDecl() &&
8199 !isa<CXXDeductionGuideDecl>(NewFD)) {
8200 if (!CurContext->isRecord()) {
8201 // 'explicit' was specified outside of the class.
8202 Diag(D.getDeclSpec().getExplicitSpecLoc(),
8203 diag::err_explicit_out_of_class)
8204 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
8205 } else if (!isa<CXXConstructorDecl>(NewFD) &&
8206 !isa<CXXConversionDecl>(NewFD)) {
8207 // 'explicit' was specified on a function that wasn't a constructor
8208 // or conversion function.
8209 Diag(D.getDeclSpec().getExplicitSpecLoc(),
8210 diag::err_explicit_non_ctor_or_conv_function)
8211 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
8216 // C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors
8217 // are implicitly inline.
8218 NewFD->setImplicitlyInline();
8220 // C++11 [dcl.constexpr]p3: functions declared constexpr are required to
8221 // be either constructors or to return a literal type. Therefore,
8222 // destructors cannot be declared constexpr.
8223 if (isa<CXXDestructorDecl>(NewFD))
8224 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor);
8228 // This is a function concept.
8229 if (FunctionTemplateDecl *FTD = NewFD->getDescribedFunctionTemplate())
8232 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
8233 // applied only to the definition of a function template [...]
8234 if (!D.isFunctionDefinition()) {
8235 Diag(D.getDeclSpec().getConceptSpecLoc(),
8236 diag::err_function_concept_not_defined);
8237 NewFD->setInvalidDecl();
8240 // C++ Concepts TS [dcl.spec.concept]p1: [...] A function concept shall
8241 // have no exception-specification and is treated as if it were specified
8242 // with noexcept(true) (15.4). [...]
8243 if (const FunctionProtoType *FPT = R->getAs<FunctionProtoType>()) {
8244 if (FPT->hasExceptionSpec()) {
8246 if (D.isFunctionDeclarator())
8247 Range = D.getFunctionTypeInfo().getExceptionSpecRange();
8248 Diag(NewFD->getLocation(), diag::err_function_concept_exception_spec)
8249 << FixItHint::CreateRemoval(Range);
8250 NewFD->setInvalidDecl();
8252 Context.adjustExceptionSpec(NewFD, EST_BasicNoexcept);
8255 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
8256 // following restrictions:
8257 // - The declared return type shall have the type bool.
8258 if (!Context.hasSameType(FPT->getReturnType(), Context.BoolTy)) {
8259 Diag(D.getIdentifierLoc(), diag::err_function_concept_bool_ret);
8260 NewFD->setInvalidDecl();
8263 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
8264 // following restrictions:
8265 // - The declaration's parameter list shall be equivalent to an empty
8267 if (FPT->getNumParams() > 0 || FPT->isVariadic())
8268 Diag(NewFD->getLocation(), diag::err_function_concept_with_params);
8271 // C++ Concepts TS [dcl.spec.concept]p2: Every concept definition is
8272 // implicity defined to be a constexpr declaration (implicitly inline)
8273 NewFD->setImplicitlyInline();
8275 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
8276 // be declared with the thread_local, inline, friend, or constexpr
8277 // specifiers, [...]
8279 Diag(D.getDeclSpec().getInlineSpecLoc(),
8280 diag::err_concept_decl_invalid_specifiers)
8282 NewFD->setInvalidDecl(true);
8286 Diag(D.getDeclSpec().getFriendSpecLoc(),
8287 diag::err_concept_decl_invalid_specifiers)
8289 NewFD->setInvalidDecl(true);
8293 Diag(D.getDeclSpec().getConstexprSpecLoc(),
8294 diag::err_concept_decl_invalid_specifiers)
8296 NewFD->setInvalidDecl(true);
8299 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
8300 // applied only to the definition of a function template or variable
8301 // template, declared in namespace scope.
8302 if (isFunctionTemplateSpecialization) {
8303 Diag(D.getDeclSpec().getConceptSpecLoc(),
8304 diag::err_concept_specified_specialization) << 1;
8305 NewFD->setInvalidDecl(true);
8310 // If __module_private__ was specified, mark the function accordingly.
8311 if (D.getDeclSpec().isModulePrivateSpecified()) {
8312 if (isFunctionTemplateSpecialization) {
8313 SourceLocation ModulePrivateLoc
8314 = D.getDeclSpec().getModulePrivateSpecLoc();
8315 Diag(ModulePrivateLoc, diag::err_module_private_specialization)
8317 << FixItHint::CreateRemoval(ModulePrivateLoc);
8319 NewFD->setModulePrivate();
8320 if (FunctionTemplate)
8321 FunctionTemplate->setModulePrivate();
8326 if (FunctionTemplate) {
8327 FunctionTemplate->setObjectOfFriendDecl();
8328 FunctionTemplate->setAccess(AS_public);
8330 NewFD->setObjectOfFriendDecl();
8331 NewFD->setAccess(AS_public);
8334 // If a function is defined as defaulted or deleted, mark it as such now.
8335 // FIXME: Does this ever happen? ActOnStartOfFunctionDef forces the function
8336 // definition kind to FDK_Definition.
8337 switch (D.getFunctionDefinitionKind()) {
8338 case FDK_Declaration:
8339 case FDK_Definition:
8343 NewFD->setDefaulted();
8347 NewFD->setDeletedAsWritten();
8351 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext &&
8352 D.isFunctionDefinition()) {
8353 // C++ [class.mfct]p2:
8354 // A member function may be defined (8.4) in its class definition, in
8355 // which case it is an inline member function (7.1.2)
8356 NewFD->setImplicitlyInline();
8359 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) &&
8360 !CurContext->isRecord()) {
8361 // C++ [class.static]p1:
8362 // A data or function member of a class may be declared static
8363 // in a class definition, in which case it is a static member of
8366 // Complain about the 'static' specifier if it's on an out-of-line
8367 // member function definition.
8368 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
8369 diag::err_static_out_of_line)
8370 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
8373 // C++11 [except.spec]p15:
8374 // A deallocation function with no exception-specification is treated
8375 // as if it were specified with noexcept(true).
8376 const FunctionProtoType *FPT = R->getAs<FunctionProtoType>();
8377 if ((Name.getCXXOverloadedOperator() == OO_Delete ||
8378 Name.getCXXOverloadedOperator() == OO_Array_Delete) &&
8379 getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec())
8380 NewFD->setType(Context.getFunctionType(
8381 FPT->getReturnType(), FPT->getParamTypes(),
8382 FPT->getExtProtoInfo().withExceptionSpec(EST_BasicNoexcept)));
8385 // Filter out previous declarations that don't match the scope.
8386 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewFD),
8387 D.getCXXScopeSpec().isNotEmpty() ||
8388 isMemberSpecialization ||
8389 isFunctionTemplateSpecialization);
8391 // Handle GNU asm-label extension (encoded as an attribute).
8392 if (Expr *E = (Expr*) D.getAsmLabel()) {
8393 // The parser guarantees this is a string.
8394 StringLiteral *SE = cast<StringLiteral>(E);
8395 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context,
8396 SE->getString(), 0));
8397 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
8398 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
8399 ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier());
8400 if (I != ExtnameUndeclaredIdentifiers.end()) {
8401 if (isDeclExternC(NewFD)) {
8402 NewFD->addAttr(I->second);
8403 ExtnameUndeclaredIdentifiers.erase(I);
8405 Diag(NewFD->getLocation(), diag::warn_redefine_extname_not_applied)
8406 << /*Variable*/0 << NewFD;
8410 // Copy the parameter declarations from the declarator D to the function
8411 // declaration NewFD, if they are available. First scavenge them into Params.
8412 SmallVector<ParmVarDecl*, 16> Params;
8414 if (D.isFunctionDeclarator(FTIIdx)) {
8415 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(FTIIdx).Fun;
8417 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs
8418 // function that takes no arguments, not a function that takes a
8419 // single void argument.
8420 // We let through "const void" here because Sema::GetTypeForDeclarator
8421 // already checks for that case.
8422 if (FTIHasNonVoidParameters(FTI) && FTI.Params[0].Param) {
8423 for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) {
8424 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
8425 assert(Param->getDeclContext() != NewFD && "Was set before ?");
8426 Param->setDeclContext(NewFD);
8427 Params.push_back(Param);
8429 if (Param->isInvalidDecl())
8430 NewFD->setInvalidDecl();
8434 if (!getLangOpts().CPlusPlus) {
8435 // In C, find all the tag declarations from the prototype and move them
8436 // into the function DeclContext. Remove them from the surrounding tag
8437 // injection context of the function, which is typically but not always
8439 DeclContext *PrototypeTagContext =
8440 getTagInjectionContext(NewFD->getLexicalDeclContext());
8441 for (NamedDecl *NonParmDecl : FTI.getDeclsInPrototype()) {
8442 auto *TD = dyn_cast<TagDecl>(NonParmDecl);
8444 // We don't want to reparent enumerators. Look at their parent enum
8447 if (auto *ECD = dyn_cast<EnumConstantDecl>(NonParmDecl))
8448 TD = cast<EnumDecl>(ECD->getDeclContext());
8452 DeclContext *TagDC = TD->getLexicalDeclContext();
8453 if (!TagDC->containsDecl(TD))
8455 TagDC->removeDecl(TD);
8456 TD->setDeclContext(NewFD);
8459 // Preserve the lexical DeclContext if it is not the surrounding tag
8460 // injection context of the FD. In this example, the semantic context of
8461 // E will be f and the lexical context will be S, while both the
8462 // semantic and lexical contexts of S will be f:
8463 // void f(struct S { enum E { a } f; } s);
8464 if (TagDC != PrototypeTagContext)
8465 TD->setLexicalDeclContext(TagDC);
8468 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) {
8469 // When we're declaring a function with a typedef, typeof, etc as in the
8470 // following example, we'll need to synthesize (unnamed)
8471 // parameters for use in the declaration.
8474 // typedef void fn(int);
8478 // Synthesize a parameter for each argument type.
8479 for (const auto &AI : FT->param_types()) {
8480 ParmVarDecl *Param =
8481 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), AI);
8482 Param->setScopeInfo(0, Params.size());
8483 Params.push_back(Param);
8486 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 &&
8487 "Should not need args for typedef of non-prototype fn");
8490 // Finally, we know we have the right number of parameters, install them.
8491 NewFD->setParams(Params);
8493 if (D.getDeclSpec().isNoreturnSpecified())
8495 ::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(),
8498 // Functions returning a variably modified type violate C99 6.7.5.2p2
8499 // because all functions have linkage.
8500 if (!NewFD->isInvalidDecl() &&
8501 NewFD->getReturnType()->isVariablyModifiedType()) {
8502 Diag(NewFD->getLocation(), diag::err_vm_func_decl);
8503 NewFD->setInvalidDecl();
8506 // Apply an implicit SectionAttr if #pragma code_seg is active.
8507 if (CodeSegStack.CurrentValue && D.isFunctionDefinition() &&
8508 !NewFD->hasAttr<SectionAttr>()) {
8510 SectionAttr::CreateImplicit(Context, SectionAttr::Declspec_allocate,
8511 CodeSegStack.CurrentValue->getString(),
8512 CodeSegStack.CurrentPragmaLocation));
8513 if (UnifySection(CodeSegStack.CurrentValue->getString(),
8514 ASTContext::PSF_Implicit | ASTContext::PSF_Execute |
8515 ASTContext::PSF_Read,
8517 NewFD->dropAttr<SectionAttr>();
8520 // Handle attributes.
8521 ProcessDeclAttributes(S, NewFD, D);
8523 if (getLangOpts().OpenCL) {
8524 // OpenCL v1.1 s6.5: Using an address space qualifier in a function return
8525 // type declaration will generate a compilation error.
8526 unsigned AddressSpace = NewFD->getReturnType().getAddressSpace();
8527 if (AddressSpace == LangAS::opencl_local ||
8528 AddressSpace == LangAS::opencl_global ||
8529 AddressSpace == LangAS::opencl_constant) {
8530 Diag(NewFD->getLocation(),
8531 diag::err_opencl_return_value_with_address_space);
8532 NewFD->setInvalidDecl();
8536 if (!getLangOpts().CPlusPlus) {
8537 // Perform semantic checking on the function declaration.
8538 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8539 CheckMain(NewFD, D.getDeclSpec());
8541 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8542 CheckMSVCRTEntryPoint(NewFD);
8544 if (!NewFD->isInvalidDecl())
8545 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8546 isMemberSpecialization));
8547 else if (!Previous.empty())
8548 // Recover gracefully from an invalid redeclaration.
8549 D.setRedeclaration(true);
8550 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8551 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8552 "previous declaration set still overloaded");
8554 // Diagnose no-prototype function declarations with calling conventions that
8555 // don't support variadic calls. Only do this in C and do it after merging
8556 // possibly prototyped redeclarations.
8557 const FunctionType *FT = NewFD->getType()->castAs<FunctionType>();
8558 if (isa<FunctionNoProtoType>(FT) && !D.isFunctionDefinition()) {
8559 CallingConv CC = FT->getExtInfo().getCC();
8560 if (!supportsVariadicCall(CC)) {
8561 // Windows system headers sometimes accidentally use stdcall without
8562 // (void) parameters, so we relax this to a warning.
8564 CC == CC_X86StdCall ? diag::warn_cconv_knr : diag::err_cconv_knr;
8565 Diag(NewFD->getLocation(), DiagID)
8566 << FunctionType::getNameForCallConv(CC);
8570 // C++11 [replacement.functions]p3:
8571 // The program's definitions shall not be specified as inline.
8573 // N.B. We diagnose declarations instead of definitions per LWG issue 2340.
8575 // Suppress the diagnostic if the function is __attribute__((used)), since
8576 // that forces an external definition to be emitted.
8577 if (D.getDeclSpec().isInlineSpecified() &&
8578 NewFD->isReplaceableGlobalAllocationFunction() &&
8579 !NewFD->hasAttr<UsedAttr>())
8580 Diag(D.getDeclSpec().getInlineSpecLoc(),
8581 diag::ext_operator_new_delete_declared_inline)
8582 << NewFD->getDeclName();
8584 // If the declarator is a template-id, translate the parser's template
8585 // argument list into our AST format.
8586 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
8587 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
8588 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
8589 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
8590 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
8591 TemplateId->NumArgs);
8592 translateTemplateArguments(TemplateArgsPtr,
8595 HasExplicitTemplateArgs = true;
8597 if (NewFD->isInvalidDecl()) {
8598 HasExplicitTemplateArgs = false;
8599 } else if (FunctionTemplate) {
8600 // Function template with explicit template arguments.
8601 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec)
8602 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc);
8604 HasExplicitTemplateArgs = false;
8606 assert((isFunctionTemplateSpecialization ||
8607 D.getDeclSpec().isFriendSpecified()) &&
8608 "should have a 'template<>' for this decl");
8609 // "friend void foo<>(int);" is an implicit specialization decl.
8610 isFunctionTemplateSpecialization = true;
8612 } else if (isFriend && isFunctionTemplateSpecialization) {
8613 // This combination is only possible in a recovery case; the user
8614 // wrote something like:
8615 // template <> friend void foo(int);
8616 // which we're recovering from as if the user had written:
8617 // friend void foo<>(int);
8618 // Go ahead and fake up a template id.
8619 HasExplicitTemplateArgs = true;
8620 TemplateArgs.setLAngleLoc(D.getIdentifierLoc());
8621 TemplateArgs.setRAngleLoc(D.getIdentifierLoc());
8624 // We do not add HD attributes to specializations here because
8625 // they may have different constexpr-ness compared to their
8626 // templates and, after maybeAddCUDAHostDeviceAttrs() is applied,
8627 // may end up with different effective targets. Instead, a
8628 // specialization inherits its target attributes from its template
8629 // in the CheckFunctionTemplateSpecialization() call below.
8630 if (getLangOpts().CUDA & !isFunctionTemplateSpecialization)
8631 maybeAddCUDAHostDeviceAttrs(NewFD, Previous);
8633 // If it's a friend (and only if it's a friend), it's possible
8634 // that either the specialized function type or the specialized
8635 // template is dependent, and therefore matching will fail. In
8636 // this case, don't check the specialization yet.
8637 bool InstantiationDependent = false;
8638 if (isFunctionTemplateSpecialization && isFriend &&
8639 (NewFD->getType()->isDependentType() || DC->isDependentContext() ||
8640 TemplateSpecializationType::anyDependentTemplateArguments(
8642 InstantiationDependent))) {
8643 assert(HasExplicitTemplateArgs &&
8644 "friend function specialization without template args");
8645 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs,
8647 NewFD->setInvalidDecl();
8648 } else if (isFunctionTemplateSpecialization) {
8649 if (CurContext->isDependentContext() && CurContext->isRecord()
8651 isDependentClassScopeExplicitSpecialization = true;
8652 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
8653 diag::ext_function_specialization_in_class :
8654 diag::err_function_specialization_in_class)
8655 << NewFD->getDeclName();
8656 } else if (CheckFunctionTemplateSpecialization(NewFD,
8657 (HasExplicitTemplateArgs ? &TemplateArgs
8660 NewFD->setInvalidDecl();
8663 // A storage-class-specifier shall not be specified in an explicit
8664 // specialization (14.7.3)
8665 FunctionTemplateSpecializationInfo *Info =
8666 NewFD->getTemplateSpecializationInfo();
8667 if (Info && SC != SC_None) {
8668 if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass())
8669 Diag(NewFD->getLocation(),
8670 diag::err_explicit_specialization_inconsistent_storage_class)
8672 << FixItHint::CreateRemoval(
8673 D.getDeclSpec().getStorageClassSpecLoc());
8676 Diag(NewFD->getLocation(),
8677 diag::ext_explicit_specialization_storage_class)
8678 << FixItHint::CreateRemoval(
8679 D.getDeclSpec().getStorageClassSpecLoc());
8681 } else if (isMemberSpecialization && isa<CXXMethodDecl>(NewFD)) {
8682 if (CheckMemberSpecialization(NewFD, Previous))
8683 NewFD->setInvalidDecl();
8686 // Perform semantic checking on the function declaration.
8687 if (!isDependentClassScopeExplicitSpecialization) {
8688 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8689 CheckMain(NewFD, D.getDeclSpec());
8691 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8692 CheckMSVCRTEntryPoint(NewFD);
8694 if (!NewFD->isInvalidDecl())
8695 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8696 isMemberSpecialization));
8697 else if (!Previous.empty())
8698 // Recover gracefully from an invalid redeclaration.
8699 D.setRedeclaration(true);
8702 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8703 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8704 "previous declaration set still overloaded");
8706 NamedDecl *PrincipalDecl = (FunctionTemplate
8707 ? cast<NamedDecl>(FunctionTemplate)
8710 if (isFriend && NewFD->getPreviousDecl()) {
8711 AccessSpecifier Access = AS_public;
8712 if (!NewFD->isInvalidDecl())
8713 Access = NewFD->getPreviousDecl()->getAccess();
8715 NewFD->setAccess(Access);
8716 if (FunctionTemplate) FunctionTemplate->setAccess(Access);
8719 if (NewFD->isOverloadedOperator() && !DC->isRecord() &&
8720 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
8721 PrincipalDecl->setNonMemberOperator();
8723 // If we have a function template, check the template parameter
8724 // list. This will check and merge default template arguments.
8725 if (FunctionTemplate) {
8726 FunctionTemplateDecl *PrevTemplate =
8727 FunctionTemplate->getPreviousDecl();
8728 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(),
8729 PrevTemplate ? PrevTemplate->getTemplateParameters()
8731 D.getDeclSpec().isFriendSpecified()
8732 ? (D.isFunctionDefinition()
8733 ? TPC_FriendFunctionTemplateDefinition
8734 : TPC_FriendFunctionTemplate)
8735 : (D.getCXXScopeSpec().isSet() &&
8736 DC && DC->isRecord() &&
8737 DC->isDependentContext())
8738 ? TPC_ClassTemplateMember
8739 : TPC_FunctionTemplate);
8742 if (NewFD->isInvalidDecl()) {
8743 // Ignore all the rest of this.
8744 } else if (!D.isRedeclaration()) {
8745 struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists,
8747 // Fake up an access specifier if it's supposed to be a class member.
8748 if (isa<CXXRecordDecl>(NewFD->getDeclContext()))
8749 NewFD->setAccess(AS_public);
8751 // Qualified decls generally require a previous declaration.
8752 if (D.getCXXScopeSpec().isSet()) {
8753 // ...with the major exception of templated-scope or
8754 // dependent-scope friend declarations.
8756 // TODO: we currently also suppress this check in dependent
8757 // contexts because (1) the parameter depth will be off when
8758 // matching friend templates and (2) we might actually be
8759 // selecting a friend based on a dependent factor. But there
8760 // are situations where these conditions don't apply and we
8761 // can actually do this check immediately.
8763 (TemplateParamLists.size() ||
8764 D.getCXXScopeSpec().getScopeRep()->isDependent() ||
8765 CurContext->isDependentContext())) {
8768 // The user tried to provide an out-of-line definition for a
8769 // function that is a member of a class or namespace, but there
8770 // was no such member function declared (C++ [class.mfct]p2,
8771 // C++ [namespace.memdef]p2). For example:
8777 // void X::f() { } // ill-formed
8779 // Complain about this problem, and attempt to suggest close
8780 // matches (e.g., those that differ only in cv-qualifiers and
8781 // whether the parameter types are references).
8783 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8784 *this, Previous, NewFD, ExtraArgs, false, nullptr)) {
8785 AddToScope = ExtraArgs.AddToScope;
8790 // Unqualified local friend declarations are required to resolve
8792 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) {
8793 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8794 *this, Previous, NewFD, ExtraArgs, true, S)) {
8795 AddToScope = ExtraArgs.AddToScope;
8799 } else if (!D.isFunctionDefinition() &&
8800 isa<CXXMethodDecl>(NewFD) && NewFD->isOutOfLine() &&
8801 !isFriend && !isFunctionTemplateSpecialization &&
8802 !isMemberSpecialization) {
8803 // An out-of-line member function declaration must also be a
8804 // definition (C++ [class.mfct]p2).
8805 // Note that this is not the case for explicit specializations of
8806 // function templates or member functions of class templates, per
8807 // C++ [temp.expl.spec]p2. We also allow these declarations as an
8808 // extension for compatibility with old SWIG code which likes to
8810 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration)
8811 << D.getCXXScopeSpec().getRange();
8815 ProcessPragmaWeak(S, NewFD);
8816 checkAttributesAfterMerging(*this, *NewFD);
8818 AddKnownFunctionAttributes(NewFD);
8820 if (NewFD->hasAttr<OverloadableAttr>() &&
8821 !NewFD->getType()->getAs<FunctionProtoType>()) {
8822 Diag(NewFD->getLocation(),
8823 diag::err_attribute_overloadable_no_prototype)
8826 // Turn this into a variadic function with no parameters.
8827 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>();
8828 FunctionProtoType::ExtProtoInfo EPI(
8829 Context.getDefaultCallingConvention(true, false));
8830 EPI.Variadic = true;
8831 EPI.ExtInfo = FT->getExtInfo();
8833 QualType R = Context.getFunctionType(FT->getReturnType(), None, EPI);
8837 // If there's a #pragma GCC visibility in scope, and this isn't a class
8838 // member, set the visibility of this function.
8839 if (!DC->isRecord() && NewFD->isExternallyVisible())
8840 AddPushedVisibilityAttribute(NewFD);
8842 // If there's a #pragma clang arc_cf_code_audited in scope, consider
8843 // marking the function.
8844 AddCFAuditedAttribute(NewFD);
8846 // If this is a function definition, check if we have to apply optnone due to
8848 if(D.isFunctionDefinition())
8849 AddRangeBasedOptnone(NewFD);
8851 // If this is the first declaration of an extern C variable, update
8852 // the map of such variables.
8853 if (NewFD->isFirstDecl() && !NewFD->isInvalidDecl() &&
8854 isIncompleteDeclExternC(*this, NewFD))
8855 RegisterLocallyScopedExternCDecl(NewFD, S);
8857 // Set this FunctionDecl's range up to the right paren.
8858 NewFD->setRangeEnd(D.getSourceRange().getEnd());
8860 if (D.isRedeclaration() && !Previous.empty()) {
8861 checkDLLAttributeRedeclaration(
8862 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewFD,
8863 isMemberSpecialization || isFunctionTemplateSpecialization,
8864 D.isFunctionDefinition());
8867 if (getLangOpts().CUDA) {
8868 IdentifierInfo *II = NewFD->getIdentifier();
8869 if (II && II->isStr("cudaConfigureCall") && !NewFD->isInvalidDecl() &&
8870 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
8871 if (!R->getAs<FunctionType>()->getReturnType()->isScalarType())
8872 Diag(NewFD->getLocation(), diag::err_config_scalar_return);
8874 Context.setcudaConfigureCallDecl(NewFD);
8877 // Variadic functions, other than a *declaration* of printf, are not allowed
8878 // in device-side CUDA code, unless someone passed
8879 // -fcuda-allow-variadic-functions.
8880 if (!getLangOpts().CUDAAllowVariadicFunctions && NewFD->isVariadic() &&
8881 (NewFD->hasAttr<CUDADeviceAttr>() ||
8882 NewFD->hasAttr<CUDAGlobalAttr>()) &&
8883 !(II && II->isStr("printf") && NewFD->isExternC() &&
8884 !D.isFunctionDefinition())) {
8885 Diag(NewFD->getLocation(), diag::err_variadic_device_fn);
8889 if (getLangOpts().CPlusPlus) {
8890 if (FunctionTemplate) {
8891 if (NewFD->isInvalidDecl())
8892 FunctionTemplate->setInvalidDecl();
8893 return FunctionTemplate;
8897 if (NewFD->hasAttr<OpenCLKernelAttr>()) {
8898 // OpenCL v1.2 s6.8 static is invalid for kernel functions.
8899 if ((getLangOpts().OpenCLVersion >= 120)
8900 && (SC == SC_Static)) {
8901 Diag(D.getIdentifierLoc(), diag::err_static_kernel);
8905 // OpenCL v1.2, s6.9 -- Kernels can only have return type void.
8906 if (!NewFD->getReturnType()->isVoidType()) {
8907 SourceRange RTRange = NewFD->getReturnTypeSourceRange();
8908 Diag(D.getIdentifierLoc(), diag::err_expected_kernel_void_return_type)
8909 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "void")
8914 llvm::SmallPtrSet<const Type *, 16> ValidTypes;
8915 for (auto Param : NewFD->parameters())
8916 checkIsValidOpenCLKernelParameter(*this, D, Param, ValidTypes);
8918 for (const ParmVarDecl *Param : NewFD->parameters()) {
8919 QualType PT = Param->getType();
8921 // OpenCL 2.0 pipe restrictions forbids pipe packet types to be non-value
8923 if (getLangOpts().OpenCLVersion >= 200) {
8924 if(const PipeType *PipeTy = PT->getAs<PipeType>()) {
8925 QualType ElemTy = PipeTy->getElementType();
8926 if (ElemTy->isReferenceType() || ElemTy->isPointerType()) {
8927 Diag(Param->getTypeSpecStartLoc(), diag::err_reference_pipe_type );
8934 MarkUnusedFileScopedDecl(NewFD);
8936 // Here we have an function template explicit specialization at class scope.
8937 // The actually specialization will be postponed to template instatiation
8938 // time via the ClassScopeFunctionSpecializationDecl node.
8939 if (isDependentClassScopeExplicitSpecialization) {
8940 ClassScopeFunctionSpecializationDecl *NewSpec =
8941 ClassScopeFunctionSpecializationDecl::Create(
8942 Context, CurContext, SourceLocation(),
8943 cast<CXXMethodDecl>(NewFD),
8944 HasExplicitTemplateArgs, TemplateArgs);
8945 CurContext->addDecl(NewSpec);
8952 /// \brief Checks if the new declaration declared in dependent context must be
8953 /// put in the same redeclaration chain as the specified declaration.
8955 /// \param D Declaration that is checked.
8956 /// \param PrevDecl Previous declaration found with proper lookup method for the
8957 /// same declaration name.
8958 /// \returns True if D must be added to the redeclaration chain which PrevDecl
8961 bool Sema::shouldLinkDependentDeclWithPrevious(Decl *D, Decl *PrevDecl) {
8962 // Any declarations should be put into redeclaration chains except for
8963 // friend declaration in a dependent context that names a function in
8966 // This allows to compile code like:
8969 // template<typename T> class C1 { friend void func() { } };
8970 // template<typename T> class C2 { friend void func() { } };
8972 // This code snippet is a valid code unless both templates are instantiated.
8973 return !(D->getLexicalDeclContext()->isDependentContext() &&
8974 D->getDeclContext()->isFileContext() &&
8975 D->getFriendObjectKind() != Decl::FOK_None);
8978 /// \brief Perform semantic checking of a new function declaration.
8980 /// Performs semantic analysis of the new function declaration
8981 /// NewFD. This routine performs all semantic checking that does not
8982 /// require the actual declarator involved in the declaration, and is
8983 /// used both for the declaration of functions as they are parsed
8984 /// (called via ActOnDeclarator) and for the declaration of functions
8985 /// that have been instantiated via C++ template instantiation (called
8986 /// via InstantiateDecl).
8988 /// \param IsMemberSpecialization whether this new function declaration is
8989 /// a member specialization (that replaces any definition provided by the
8990 /// previous declaration).
8992 /// This sets NewFD->isInvalidDecl() to true if there was an error.
8994 /// \returns true if the function declaration is a redeclaration.
8995 bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
8996 LookupResult &Previous,
8997 bool IsMemberSpecialization) {
8998 assert(!NewFD->getReturnType()->isVariablyModifiedType() &&
8999 "Variably modified return types are not handled here");
9001 // Determine whether the type of this function should be merged with
9002 // a previous visible declaration. This never happens for functions in C++,
9003 // and always happens in C if the previous declaration was visible.
9004 bool MergeTypeWithPrevious = !getLangOpts().CPlusPlus &&
9005 !Previous.isShadowed();
9007 bool Redeclaration = false;
9008 NamedDecl *OldDecl = nullptr;
9010 // Merge or overload the declaration with an existing declaration of
9011 // the same name, if appropriate.
9012 if (!Previous.empty()) {
9013 // Determine whether NewFD is an overload of PrevDecl or
9014 // a declaration that requires merging. If it's an overload,
9015 // there's no more work to do here; we'll just add the new
9016 // function to the scope.
9017 if (!AllowOverloadingOfFunction(Previous, Context)) {
9018 NamedDecl *Candidate = Previous.getRepresentativeDecl();
9019 if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) {
9020 Redeclaration = true;
9021 OldDecl = Candidate;
9024 switch (CheckOverload(S, NewFD, Previous, OldDecl,
9025 /*NewIsUsingDecl*/ false)) {
9027 Redeclaration = true;
9030 case Ovl_NonFunction:
9031 Redeclaration = true;
9035 Redeclaration = false;
9039 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
9040 // If a function name is overloadable in C, then every function
9041 // with that name must be marked "overloadable".
9042 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
9043 << Redeclaration << NewFD;
9044 NamedDecl *OverloadedDecl =
9045 Redeclaration ? OldDecl : Previous.getRepresentativeDecl();
9046 Diag(OverloadedDecl->getLocation(),
9047 diag::note_attribute_overloadable_prev_overload);
9048 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
9053 // Check for a previous extern "C" declaration with this name.
9054 if (!Redeclaration &&
9055 checkForConflictWithNonVisibleExternC(*this, NewFD, Previous)) {
9056 if (!Previous.empty()) {
9057 // This is an extern "C" declaration with the same name as a previous
9058 // declaration, and thus redeclares that entity...
9059 Redeclaration = true;
9060 OldDecl = Previous.getFoundDecl();
9061 MergeTypeWithPrevious = false;
9063 // ... except in the presence of __attribute__((overloadable)).
9064 if (OldDecl->hasAttr<OverloadableAttr>()) {
9065 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
9066 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
9067 << Redeclaration << NewFD;
9068 Diag(Previous.getFoundDecl()->getLocation(),
9069 diag::note_attribute_overloadable_prev_overload);
9070 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
9072 if (IsOverload(NewFD, cast<FunctionDecl>(OldDecl), false)) {
9073 Redeclaration = false;
9080 // C++11 [dcl.constexpr]p8:
9081 // A constexpr specifier for a non-static member function that is not
9082 // a constructor declares that member function to be const.
9084 // This needs to be delayed until we know whether this is an out-of-line
9085 // definition of a static member function.
9087 // This rule is not present in C++1y, so we produce a backwards
9088 // compatibility warning whenever it happens in C++11.
9089 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
9090 if (!getLangOpts().CPlusPlus14 && MD && MD->isConstexpr() &&
9091 !MD->isStatic() && !isa<CXXConstructorDecl>(MD) &&
9092 (MD->getTypeQualifiers() & Qualifiers::Const) == 0) {
9093 CXXMethodDecl *OldMD = nullptr;
9095 OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl->getAsFunction());
9096 if (!OldMD || !OldMD->isStatic()) {
9097 const FunctionProtoType *FPT =
9098 MD->getType()->castAs<FunctionProtoType>();
9099 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
9100 EPI.TypeQuals |= Qualifiers::Const;
9101 MD->setType(Context.getFunctionType(FPT->getReturnType(),
9102 FPT->getParamTypes(), EPI));
9104 // Warn that we did this, if we're not performing template instantiation.
9105 // In that case, we'll have warned already when the template was defined.
9106 if (!inTemplateInstantiation()) {
9107 SourceLocation AddConstLoc;
9108 if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
9109 .IgnoreParens().getAs<FunctionTypeLoc>())
9110 AddConstLoc = getLocForEndOfToken(FTL.getRParenLoc());
9112 Diag(MD->getLocation(), diag::warn_cxx14_compat_constexpr_not_const)
9113 << FixItHint::CreateInsertion(AddConstLoc, " const");
9118 if (Redeclaration) {
9119 // NewFD and OldDecl represent declarations that need to be
9121 if (MergeFunctionDecl(NewFD, OldDecl, S, MergeTypeWithPrevious)) {
9122 NewFD->setInvalidDecl();
9123 return Redeclaration;
9127 Previous.addDecl(OldDecl);
9129 if (FunctionTemplateDecl *OldTemplateDecl
9130 = dyn_cast<FunctionTemplateDecl>(OldDecl)) {
9131 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl());
9132 FunctionTemplateDecl *NewTemplateDecl
9133 = NewFD->getDescribedFunctionTemplate();
9134 assert(NewTemplateDecl && "Template/non-template mismatch");
9135 if (CXXMethodDecl *Method
9136 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) {
9137 Method->setAccess(OldTemplateDecl->getAccess());
9138 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess());
9141 // If this is an explicit specialization of a member that is a function
9142 // template, mark it as a member specialization.
9143 if (IsMemberSpecialization &&
9144 NewTemplateDecl->getInstantiatedFromMemberTemplate()) {
9145 NewTemplateDecl->setMemberSpecialization();
9146 assert(OldTemplateDecl->isMemberSpecialization());
9147 // Explicit specializations of a member template do not inherit deleted
9148 // status from the parent member template that they are specializing.
9149 if (OldTemplateDecl->getTemplatedDecl()->isDeleted()) {
9150 FunctionDecl *const OldTemplatedDecl =
9151 OldTemplateDecl->getTemplatedDecl();
9152 assert(OldTemplatedDecl->getCanonicalDecl() == OldTemplatedDecl);
9153 OldTemplatedDecl->setDeletedAsWritten(false);
9158 if (shouldLinkDependentDeclWithPrevious(NewFD, OldDecl)) {
9159 // This needs to happen first so that 'inline' propagates.
9160 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl));
9161 if (isa<CXXMethodDecl>(NewFD))
9162 NewFD->setAccess(OldDecl->getAccess());
9167 // Semantic checking for this function declaration (in isolation).
9169 if (getLangOpts().CPlusPlus) {
9170 // C++-specific checks.
9171 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) {
9172 CheckConstructor(Constructor);
9173 } else if (CXXDestructorDecl *Destructor =
9174 dyn_cast<CXXDestructorDecl>(NewFD)) {
9175 CXXRecordDecl *Record = Destructor->getParent();
9176 QualType ClassType = Context.getTypeDeclType(Record);
9178 // FIXME: Shouldn't we be able to perform this check even when the class
9179 // type is dependent? Both gcc and edg can handle that.
9180 if (!ClassType->isDependentType()) {
9181 DeclarationName Name
9182 = Context.DeclarationNames.getCXXDestructorName(
9183 Context.getCanonicalType(ClassType));
9184 if (NewFD->getDeclName() != Name) {
9185 Diag(NewFD->getLocation(), diag::err_destructor_name);
9186 NewFD->setInvalidDecl();
9187 return Redeclaration;
9190 } else if (CXXConversionDecl *Conversion
9191 = dyn_cast<CXXConversionDecl>(NewFD)) {
9192 ActOnConversionDeclarator(Conversion);
9193 } else if (auto *Guide = dyn_cast<CXXDeductionGuideDecl>(NewFD)) {
9194 if (auto *TD = Guide->getDescribedFunctionTemplate())
9195 CheckDeductionGuideTemplate(TD);
9197 // A deduction guide is not on the list of entities that can be
9198 // explicitly specialized.
9199 if (Guide->getTemplateSpecializationKind() == TSK_ExplicitSpecialization)
9200 Diag(Guide->getLocStart(), diag::err_deduction_guide_specialized)
9201 << /*explicit specialization*/ 1;
9204 // Find any virtual functions that this function overrides.
9205 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) {
9206 if (!Method->isFunctionTemplateSpecialization() &&
9207 !Method->getDescribedFunctionTemplate() &&
9208 Method->isCanonicalDecl()) {
9209 if (AddOverriddenMethods(Method->getParent(), Method)) {
9210 // If the function was marked as "static", we have a problem.
9211 if (NewFD->getStorageClass() == SC_Static) {
9212 ReportOverrides(*this, diag::err_static_overrides_virtual, Method);
9217 if (Method->isStatic())
9218 checkThisInStaticMemberFunctionType(Method);
9221 // Extra checking for C++ overloaded operators (C++ [over.oper]).
9222 if (NewFD->isOverloadedOperator() &&
9223 CheckOverloadedOperatorDeclaration(NewFD)) {
9224 NewFD->setInvalidDecl();
9225 return Redeclaration;
9228 // Extra checking for C++0x literal operators (C++0x [over.literal]).
9229 if (NewFD->getLiteralIdentifier() &&
9230 CheckLiteralOperatorDeclaration(NewFD)) {
9231 NewFD->setInvalidDecl();
9232 return Redeclaration;
9235 // In C++, check default arguments now that we have merged decls. Unless
9236 // the lexical context is the class, because in this case this is done
9237 // during delayed parsing anyway.
9238 if (!CurContext->isRecord())
9239 CheckCXXDefaultArguments(NewFD);
9241 // If this function declares a builtin function, check the type of this
9242 // declaration against the expected type for the builtin.
9243 if (unsigned BuiltinID = NewFD->getBuiltinID()) {
9244 ASTContext::GetBuiltinTypeError Error;
9245 LookupPredefedObjCSuperType(*this, S, NewFD->getIdentifier());
9246 QualType T = Context.GetBuiltinType(BuiltinID, Error);
9247 // If the type of the builtin differs only in its exception
9248 // specification, that's OK.
9249 // FIXME: If the types do differ in this way, it would be better to
9250 // retain the 'noexcept' form of the type.
9252 !Context.hasSameFunctionTypeIgnoringExceptionSpec(T,
9254 // The type of this function differs from the type of the builtin,
9255 // so forget about the builtin entirely.
9256 Context.BuiltinInfo.forgetBuiltin(BuiltinID, Context.Idents);
9259 // If this function is declared as being extern "C", then check to see if
9260 // the function returns a UDT (class, struct, or union type) that is not C
9261 // compatible, and if it does, warn the user.
9262 // But, issue any diagnostic on the first declaration only.
9263 if (Previous.empty() && NewFD->isExternC()) {
9264 QualType R = NewFD->getReturnType();
9265 if (R->isIncompleteType() && !R->isVoidType())
9266 Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete)
9268 else if (!R.isPODType(Context) && !R->isVoidType() &&
9269 !R->isObjCObjectPointerType())
9270 Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R;
9273 // C++1z [dcl.fct]p6:
9274 // [...] whether the function has a non-throwing exception-specification
9275 // [is] part of the function type
9277 // This results in an ABI break between C++14 and C++17 for functions whose
9278 // declared type includes an exception-specification in a parameter or
9279 // return type. (Exception specifications on the function itself are OK in
9280 // most cases, and exception specifications are not permitted in most other
9281 // contexts where they could make it into a mangling.)
9282 if (!getLangOpts().CPlusPlus1z && !NewFD->getPrimaryTemplate()) {
9283 auto HasNoexcept = [&](QualType T) -> bool {
9284 // Strip off declarator chunks that could be between us and a function
9285 // type. We don't need to look far, exception specifications are very
9286 // restricted prior to C++17.
9287 if (auto *RT = T->getAs<ReferenceType>())
9288 T = RT->getPointeeType();
9289 else if (T->isAnyPointerType())
9290 T = T->getPointeeType();
9291 else if (auto *MPT = T->getAs<MemberPointerType>())
9292 T = MPT->getPointeeType();
9293 if (auto *FPT = T->getAs<FunctionProtoType>())
9294 if (FPT->isNothrow(Context))
9299 auto *FPT = NewFD->getType()->castAs<FunctionProtoType>();
9300 bool AnyNoexcept = HasNoexcept(FPT->getReturnType());
9301 for (QualType T : FPT->param_types())
9302 AnyNoexcept |= HasNoexcept(T);
9304 Diag(NewFD->getLocation(),
9305 diag::warn_cxx1z_compat_exception_spec_in_signature)
9309 if (!Redeclaration && LangOpts.CUDA)
9310 checkCUDATargetOverload(NewFD, Previous);
9312 return Redeclaration;
9315 void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) {
9316 // C++11 [basic.start.main]p3:
9317 // A program that [...] declares main to be inline, static or
9318 // constexpr is ill-formed.
9319 // C11 6.7.4p4: In a hosted environment, no function specifier(s) shall
9320 // appear in a declaration of main.
9321 // static main is not an error under C99, but we should warn about it.
9322 // We accept _Noreturn main as an extension.
9323 if (FD->getStorageClass() == SC_Static)
9324 Diag(DS.getStorageClassSpecLoc(), getLangOpts().CPlusPlus
9325 ? diag::err_static_main : diag::warn_static_main)
9326 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
9327 if (FD->isInlineSpecified())
9328 Diag(DS.getInlineSpecLoc(), diag::err_inline_main)
9329 << FixItHint::CreateRemoval(DS.getInlineSpecLoc());
9330 if (DS.isNoreturnSpecified()) {
9331 SourceLocation NoreturnLoc = DS.getNoreturnSpecLoc();
9332 SourceRange NoreturnRange(NoreturnLoc, getLocForEndOfToken(NoreturnLoc));
9333 Diag(NoreturnLoc, diag::ext_noreturn_main);
9334 Diag(NoreturnLoc, diag::note_main_remove_noreturn)
9335 << FixItHint::CreateRemoval(NoreturnRange);
9337 if (FD->isConstexpr()) {
9338 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_main)
9339 << FixItHint::CreateRemoval(DS.getConstexprSpecLoc());
9340 FD->setConstexpr(false);
9343 if (getLangOpts().OpenCL) {
9344 Diag(FD->getLocation(), diag::err_opencl_no_main)
9345 << FD->hasAttr<OpenCLKernelAttr>();
9346 FD->setInvalidDecl();
9350 QualType T = FD->getType();
9351 assert(T->isFunctionType() && "function decl is not of function type");
9352 const FunctionType* FT = T->castAs<FunctionType>();
9354 if (getLangOpts().GNUMode && !getLangOpts().CPlusPlus) {
9355 // In C with GNU extensions we allow main() to have non-integer return
9356 // type, but we should warn about the extension, and we disable the
9357 // implicit-return-zero rule.
9359 // GCC in C mode accepts qualified 'int'.
9360 if (Context.hasSameUnqualifiedType(FT->getReturnType(), Context.IntTy))
9361 FD->setHasImplicitReturnZero(true);
9363 Diag(FD->getTypeSpecStartLoc(), diag::ext_main_returns_nonint);
9364 SourceRange RTRange = FD->getReturnTypeSourceRange();
9365 if (RTRange.isValid())
9366 Diag(RTRange.getBegin(), diag::note_main_change_return_type)
9367 << FixItHint::CreateReplacement(RTRange, "int");
9370 // In C and C++, main magically returns 0 if you fall off the end;
9371 // set the flag which tells us that.
9372 // This is C++ [basic.start.main]p5 and C99 5.1.2.2.3.
9374 // All the standards say that main() should return 'int'.
9375 if (Context.hasSameType(FT->getReturnType(), Context.IntTy))
9376 FD->setHasImplicitReturnZero(true);
9378 // Otherwise, this is just a flat-out error.
9379 SourceRange RTRange = FD->getReturnTypeSourceRange();
9380 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint)
9381 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "int")
9383 FD->setInvalidDecl(true);
9387 // Treat protoless main() as nullary.
9388 if (isa<FunctionNoProtoType>(FT)) return;
9390 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT);
9391 unsigned nparams = FTP->getNumParams();
9392 assert(FD->getNumParams() == nparams);
9394 bool HasExtraParameters = (nparams > 3);
9396 if (FTP->isVariadic()) {
9397 Diag(FD->getLocation(), diag::ext_variadic_main);
9398 // FIXME: if we had information about the location of the ellipsis, we
9399 // could add a FixIt hint to remove it as a parameter.
9402 // Darwin passes an undocumented fourth argument of type char**. If
9403 // other platforms start sprouting these, the logic below will start
9405 if (nparams == 4 && Context.getTargetInfo().getTriple().isOSDarwin())
9406 HasExtraParameters = false;
9408 if (HasExtraParameters) {
9409 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams;
9410 FD->setInvalidDecl(true);
9414 // FIXME: a lot of the following diagnostics would be improved
9415 // if we had some location information about types.
9418 Context.getPointerType(Context.getPointerType(Context.CharTy));
9419 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP };
9421 for (unsigned i = 0; i < nparams; ++i) {
9422 QualType AT = FTP->getParamType(i);
9424 bool mismatch = true;
9426 if (Context.hasSameUnqualifiedType(AT, Expected[i]))
9428 else if (Expected[i] == CharPP) {
9429 // As an extension, the following forms are okay:
9431 // char const * const *
9434 QualifierCollector qs;
9435 const PointerType* PT;
9436 if ((PT = qs.strip(AT)->getAs<PointerType>()) &&
9437 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) &&
9438 Context.hasSameType(QualType(qs.strip(PT->getPointeeType()), 0),
9441 mismatch = !qs.empty();
9446 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i];
9447 // TODO: suggest replacing given type with expected type
9448 FD->setInvalidDecl(true);
9452 if (nparams == 1 && !FD->isInvalidDecl()) {
9453 Diag(FD->getLocation(), diag::warn_main_one_arg);
9456 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
9457 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
9458 FD->setInvalidDecl();
9462 void Sema::CheckMSVCRTEntryPoint(FunctionDecl *FD) {
9463 QualType T = FD->getType();
9464 assert(T->isFunctionType() && "function decl is not of function type");
9465 const FunctionType *FT = T->castAs<FunctionType>();
9467 // Set an implicit return of 'zero' if the function can return some integral,
9468 // enumeration, pointer or nullptr type.
9469 if (FT->getReturnType()->isIntegralOrEnumerationType() ||
9470 FT->getReturnType()->isAnyPointerType() ||
9471 FT->getReturnType()->isNullPtrType())
9472 // DllMain is exempt because a return value of zero means it failed.
9473 if (FD->getName() != "DllMain")
9474 FD->setHasImplicitReturnZero(true);
9476 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
9477 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
9478 FD->setInvalidDecl();
9482 bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
9483 // FIXME: Need strict checking. In C89, we need to check for
9484 // any assignment, increment, decrement, function-calls, or
9485 // commas outside of a sizeof. In C99, it's the same list,
9486 // except that the aforementioned are allowed in unevaluated
9487 // expressions. Everything else falls under the
9488 // "may accept other forms of constant expressions" exception.
9489 // (We never end up here for C++, so the constant expression
9490 // rules there don't matter.)
9491 const Expr *Culprit;
9492 if (Init->isConstantInitializer(Context, false, &Culprit))
9494 Diag(Culprit->getExprLoc(), diag::err_init_element_not_constant)
9495 << Culprit->getSourceRange();
9500 // Visits an initialization expression to see if OrigDecl is evaluated in
9501 // its own initialization and throws a warning if it does.
9502 class SelfReferenceChecker
9503 : public EvaluatedExprVisitor<SelfReferenceChecker> {
9508 bool isReferenceType;
9511 llvm::SmallVector<unsigned, 4> InitFieldIndex;
9514 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited;
9516 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context),
9517 S(S), OrigDecl(OrigDecl) {
9519 isRecordType = false;
9520 isReferenceType = false;
9522 if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) {
9523 isPODType = VD->getType().isPODType(S.Context);
9524 isRecordType = VD->getType()->isRecordType();
9525 isReferenceType = VD->getType()->isReferenceType();
9529 // For most expressions, just call the visitor. For initializer lists,
9530 // track the index of the field being initialized since fields are
9531 // initialized in order allowing use of previously initialized fields.
9532 void CheckExpr(Expr *E) {
9533 InitListExpr *InitList = dyn_cast<InitListExpr>(E);
9539 // Track and increment the index here.
9541 InitFieldIndex.push_back(0);
9542 for (auto Child : InitList->children()) {
9543 CheckExpr(cast<Expr>(Child));
9544 ++InitFieldIndex.back();
9546 InitFieldIndex.pop_back();
9549 // Returns true if MemberExpr is checked and no further checking is needed.
9550 // Returns false if additional checking is required.
9551 bool CheckInitListMemberExpr(MemberExpr *E, bool CheckReference) {
9552 llvm::SmallVector<FieldDecl*, 4> Fields;
9554 bool ReferenceField = false;
9556 // Get the field memebers used.
9557 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9558 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
9561 Fields.push_back(FD);
9562 if (FD->getType()->isReferenceType())
9563 ReferenceField = true;
9564 Base = ME->getBase()->IgnoreParenImpCasts();
9567 // Keep checking only if the base Decl is the same.
9568 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base);
9569 if (!DRE || DRE->getDecl() != OrigDecl)
9572 // A reference field can be bound to an unininitialized field.
9573 if (CheckReference && !ReferenceField)
9576 // Convert FieldDecls to their index number.
9577 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
9578 for (const FieldDecl *I : llvm::reverse(Fields))
9579 UsedFieldIndex.push_back(I->getFieldIndex());
9581 // See if a warning is needed by checking the first difference in index
9582 // numbers. If field being used has index less than the field being
9583 // initialized, then the use is safe.
9584 for (auto UsedIter = UsedFieldIndex.begin(),
9585 UsedEnd = UsedFieldIndex.end(),
9586 OrigIter = InitFieldIndex.begin(),
9587 OrigEnd = InitFieldIndex.end();
9588 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
9589 if (*UsedIter < *OrigIter)
9591 if (*UsedIter > *OrigIter)
9595 // TODO: Add a different warning which will print the field names.
9596 HandleDeclRefExpr(DRE);
9600 // For most expressions, the cast is directly above the DeclRefExpr.
9601 // For conditional operators, the cast can be outside the conditional
9602 // operator if both expressions are DeclRefExpr's.
9603 void HandleValue(Expr *E) {
9604 E = E->IgnoreParens();
9605 if (DeclRefExpr* DRE = dyn_cast<DeclRefExpr>(E)) {
9606 HandleDeclRefExpr(DRE);
9610 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
9611 Visit(CO->getCond());
9612 HandleValue(CO->getTrueExpr());
9613 HandleValue(CO->getFalseExpr());
9617 if (BinaryConditionalOperator *BCO =
9618 dyn_cast<BinaryConditionalOperator>(E)) {
9619 Visit(BCO->getCond());
9620 HandleValue(BCO->getFalseExpr());
9624 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
9625 HandleValue(OVE->getSourceExpr());
9629 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
9630 if (BO->getOpcode() == BO_Comma) {
9631 Visit(BO->getLHS());
9632 HandleValue(BO->getRHS());
9637 if (isa<MemberExpr>(E)) {
9639 if (CheckInitListMemberExpr(cast<MemberExpr>(E),
9640 false /*CheckReference*/))
9644 Expr *Base = E->IgnoreParenImpCasts();
9645 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9646 // Check for static member variables and don't warn on them.
9647 if (!isa<FieldDecl>(ME->getMemberDecl()))
9649 Base = ME->getBase()->IgnoreParenImpCasts();
9651 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base))
9652 HandleDeclRefExpr(DRE);
9659 // Reference types not handled in HandleValue are handled here since all
9660 // uses of references are bad, not just r-value uses.
9661 void VisitDeclRefExpr(DeclRefExpr *E) {
9662 if (isReferenceType)
9663 HandleDeclRefExpr(E);
9666 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
9667 if (E->getCastKind() == CK_LValueToRValue) {
9668 HandleValue(E->getSubExpr());
9672 Inherited::VisitImplicitCastExpr(E);
9675 void VisitMemberExpr(MemberExpr *E) {
9677 if (CheckInitListMemberExpr(E, true /*CheckReference*/))
9681 // Don't warn on arrays since they can be treated as pointers.
9682 if (E->getType()->canDecayToPointerType()) return;
9684 // Warn when a non-static method call is followed by non-static member
9685 // field accesses, which is followed by a DeclRefExpr.
9686 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl());
9687 bool Warn = (MD && !MD->isStatic());
9688 Expr *Base = E->getBase()->IgnoreParenImpCasts();
9689 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9690 if (!isa<FieldDecl>(ME->getMemberDecl()))
9692 Base = ME->getBase()->IgnoreParenImpCasts();
9695 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
9697 HandleDeclRefExpr(DRE);
9701 // The base of a MemberExpr is not a MemberExpr or a DeclRefExpr.
9702 // Visit that expression.
9706 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
9707 Expr *Callee = E->getCallee();
9709 if (isa<UnresolvedLookupExpr>(Callee))
9710 return Inherited::VisitCXXOperatorCallExpr(E);
9713 for (auto Arg: E->arguments())
9714 HandleValue(Arg->IgnoreParenImpCasts());
9717 void VisitUnaryOperator(UnaryOperator *E) {
9718 // For POD record types, addresses of its own members are well-defined.
9719 if (E->getOpcode() == UO_AddrOf && isRecordType &&
9720 isa<MemberExpr>(E->getSubExpr()->IgnoreParens())) {
9722 HandleValue(E->getSubExpr());
9726 if (E->isIncrementDecrementOp()) {
9727 HandleValue(E->getSubExpr());
9731 Inherited::VisitUnaryOperator(E);
9734 void VisitObjCMessageExpr(ObjCMessageExpr *E) {}
9736 void VisitCXXConstructExpr(CXXConstructExpr *E) {
9737 if (E->getConstructor()->isCopyConstructor()) {
9738 Expr *ArgExpr = E->getArg(0);
9739 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
9740 if (ILE->getNumInits() == 1)
9741 ArgExpr = ILE->getInit(0);
9742 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
9743 if (ICE->getCastKind() == CK_NoOp)
9744 ArgExpr = ICE->getSubExpr();
9745 HandleValue(ArgExpr);
9748 Inherited::VisitCXXConstructExpr(E);
9751 void VisitCallExpr(CallExpr *E) {
9752 // Treat std::move as a use.
9753 if (E->getNumArgs() == 1) {
9754 if (FunctionDecl *FD = E->getDirectCallee()) {
9755 if (FD->isInStdNamespace() && FD->getIdentifier() &&
9756 FD->getIdentifier()->isStr("move")) {
9757 HandleValue(E->getArg(0));
9763 Inherited::VisitCallExpr(E);
9766 void VisitBinaryOperator(BinaryOperator *E) {
9767 if (E->isCompoundAssignmentOp()) {
9768 HandleValue(E->getLHS());
9773 Inherited::VisitBinaryOperator(E);
9776 // A custom visitor for BinaryConditionalOperator is needed because the
9777 // regular visitor would check the condition and true expression separately
9778 // but both point to the same place giving duplicate diagnostics.
9779 void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
9780 Visit(E->getCond());
9781 Visit(E->getFalseExpr());
9784 void HandleDeclRefExpr(DeclRefExpr *DRE) {
9785 Decl* ReferenceDecl = DRE->getDecl();
9786 if (OrigDecl != ReferenceDecl) return;
9788 if (isReferenceType) {
9789 diag = diag::warn_uninit_self_reference_in_reference_init;
9790 } else if (cast<VarDecl>(OrigDecl)->isStaticLocal()) {
9791 diag = diag::warn_static_self_reference_in_init;
9792 } else if (isa<TranslationUnitDecl>(OrigDecl->getDeclContext()) ||
9793 isa<NamespaceDecl>(OrigDecl->getDeclContext()) ||
9794 DRE->getDecl()->getType()->isRecordType()) {
9795 diag = diag::warn_uninit_self_reference_in_init;
9797 // Local variables will be handled by the CFG analysis.
9801 S.DiagRuntimeBehavior(DRE->getLocStart(), DRE,
9803 << DRE->getNameInfo().getName()
9804 << OrigDecl->getLocation()
9805 << DRE->getSourceRange());
9809 /// CheckSelfReference - Warns if OrigDecl is used in expression E.
9810 static void CheckSelfReference(Sema &S, Decl* OrigDecl, Expr *E,
9812 // Parameters arguments are occassionially constructed with itself,
9813 // for instance, in recursive functions. Skip them.
9814 if (isa<ParmVarDecl>(OrigDecl))
9817 E = E->IgnoreParens();
9819 // Skip checking T a = a where T is not a record or reference type.
9820 // Doing so is a way to silence uninitialized warnings.
9821 if (!DirectInit && !cast<VarDecl>(OrigDecl)->getType()->isRecordType())
9822 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
9823 if (ICE->getCastKind() == CK_LValueToRValue)
9824 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()))
9825 if (DRE->getDecl() == OrigDecl)
9828 SelfReferenceChecker(S, OrigDecl).CheckExpr(E);
9830 } // end anonymous namespace
9833 // Simple wrapper to add the name of a variable or (if no variable is
9834 // available) a DeclarationName into a diagnostic.
9835 struct VarDeclOrName {
9837 DeclarationName Name;
9839 friend const Sema::SemaDiagnosticBuilder &
9840 operator<<(const Sema::SemaDiagnosticBuilder &Diag, VarDeclOrName VN) {
9841 return VN.VDecl ? Diag << VN.VDecl : Diag << VN.Name;
9844 } // end anonymous namespace
9846 QualType Sema::deduceVarTypeFromInitializer(VarDecl *VDecl,
9847 DeclarationName Name, QualType Type,
9848 TypeSourceInfo *TSI,
9849 SourceRange Range, bool DirectInit,
9851 bool IsInitCapture = !VDecl;
9852 assert((!VDecl || !VDecl->isInitCapture()) &&
9853 "init captures are expected to be deduced prior to initialization");
9855 VarDeclOrName VN{VDecl, Name};
9857 DeducedType *Deduced = Type->getContainedDeducedType();
9858 assert(Deduced && "deduceVarTypeFromInitializer for non-deduced type");
9860 // C++11 [dcl.spec.auto]p3
9862 assert(VDecl && "no init for init capture deduction?");
9863 Diag(VDecl->getLocation(), diag::err_auto_var_requires_init)
9864 << VDecl->getDeclName() << Type;
9868 ArrayRef<Expr*> DeduceInits = Init;
9870 if (auto *PL = dyn_cast_or_null<ParenListExpr>(Init))
9871 DeduceInits = PL->exprs();
9874 if (isa<DeducedTemplateSpecializationType>(Deduced)) {
9875 assert(VDecl && "non-auto type for init capture deduction?");
9876 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
9877 InitializationKind Kind = InitializationKind::CreateForInit(
9878 VDecl->getLocation(), DirectInit, Init);
9879 // FIXME: Initialization should not be taking a mutable list of inits.
9880 SmallVector<Expr*, 8> InitsCopy(DeduceInits.begin(), DeduceInits.end());
9881 return DeduceTemplateSpecializationFromInitializer(TSI, Entity, Kind,
9886 if (auto *IL = dyn_cast<InitListExpr>(Init))
9887 DeduceInits = IL->inits();
9890 // Deduction only works if we have exactly one source expression.
9891 if (DeduceInits.empty()) {
9892 // It isn't possible to write this directly, but it is possible to
9893 // end up in this situation with "auto x(some_pack...);"
9894 Diag(Init->getLocStart(), IsInitCapture
9895 ? diag::err_init_capture_no_expression
9896 : diag::err_auto_var_init_no_expression)
9897 << VN << Type << Range;
9901 if (DeduceInits.size() > 1) {
9902 Diag(DeduceInits[1]->getLocStart(),
9903 IsInitCapture ? diag::err_init_capture_multiple_expressions
9904 : diag::err_auto_var_init_multiple_expressions)
9905 << VN << Type << Range;
9909 Expr *DeduceInit = DeduceInits[0];
9910 if (DirectInit && isa<InitListExpr>(DeduceInit)) {
9911 Diag(Init->getLocStart(), IsInitCapture
9912 ? diag::err_init_capture_paren_braces
9913 : diag::err_auto_var_init_paren_braces)
9914 << isa<InitListExpr>(Init) << VN << Type << Range;
9918 // Expressions default to 'id' when we're in a debugger.
9919 bool DefaultedAnyToId = false;
9920 if (getLangOpts().DebuggerCastResultToId &&
9921 Init->getType() == Context.UnknownAnyTy && !IsInitCapture) {
9922 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
9923 if (Result.isInvalid()) {
9926 Init = Result.get();
9927 DefaultedAnyToId = true;
9930 // C++ [dcl.decomp]p1:
9931 // If the assignment-expression [...] has array type A and no ref-qualifier
9932 // is present, e has type cv A
9933 if (VDecl && isa<DecompositionDecl>(VDecl) &&
9934 Context.hasSameUnqualifiedType(Type, Context.getAutoDeductType()) &&
9935 DeduceInit->getType()->isConstantArrayType())
9936 return Context.getQualifiedType(DeduceInit->getType(),
9937 Type.getQualifiers());
9939 QualType DeducedType;
9940 if (DeduceAutoType(TSI, DeduceInit, DeducedType) == DAR_Failed) {
9942 DiagnoseAutoDeductionFailure(VDecl, DeduceInit);
9943 else if (isa<InitListExpr>(Init))
9944 Diag(Range.getBegin(),
9945 diag::err_init_capture_deduction_failure_from_init_list)
9947 << (DeduceInit->getType().isNull() ? TSI->getType()
9948 : DeduceInit->getType())
9949 << DeduceInit->getSourceRange();
9951 Diag(Range.getBegin(), diag::err_init_capture_deduction_failure)
9952 << VN << TSI->getType()
9953 << (DeduceInit->getType().isNull() ? TSI->getType()
9954 : DeduceInit->getType())
9955 << DeduceInit->getSourceRange();
9958 // Warn if we deduced 'id'. 'auto' usually implies type-safety, but using
9959 // 'id' instead of a specific object type prevents most of our usual
9961 // We only want to warn outside of template instantiations, though:
9962 // inside a template, the 'id' could have come from a parameter.
9963 if (!inTemplateInstantiation() && !DefaultedAnyToId && !IsInitCapture &&
9964 !DeducedType.isNull() && DeducedType->isObjCIdType()) {
9965 SourceLocation Loc = TSI->getTypeLoc().getBeginLoc();
9966 Diag(Loc, diag::warn_auto_var_is_id) << VN << Range;
9972 bool Sema::DeduceVariableDeclarationType(VarDecl *VDecl, bool DirectInit,
9974 QualType DeducedType = deduceVarTypeFromInitializer(
9975 VDecl, VDecl->getDeclName(), VDecl->getType(), VDecl->getTypeSourceInfo(),
9976 VDecl->getSourceRange(), DirectInit, Init);
9977 if (DeducedType.isNull()) {
9978 VDecl->setInvalidDecl();
9982 VDecl->setType(DeducedType);
9983 assert(VDecl->isLinkageValid());
9985 // In ARC, infer lifetime.
9986 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(VDecl))
9987 VDecl->setInvalidDecl();
9989 // If this is a redeclaration, check that the type we just deduced matches
9990 // the previously declared type.
9991 if (VarDecl *Old = VDecl->getPreviousDecl()) {
9992 // We never need to merge the type, because we cannot form an incomplete
9993 // array of auto, nor deduce such a type.
9994 MergeVarDeclTypes(VDecl, Old, /*MergeTypeWithPrevious*/ false);
9997 // Check the deduced type is valid for a variable declaration.
9998 CheckVariableDeclarationType(VDecl);
9999 return VDecl->isInvalidDecl();
10002 /// AddInitializerToDecl - Adds the initializer Init to the
10003 /// declaration dcl. If DirectInit is true, this is C++ direct
10004 /// initialization rather than copy initialization.
10005 void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) {
10006 // If there is no declaration, there was an error parsing it. Just ignore
10007 // the initializer.
10008 if (!RealDecl || RealDecl->isInvalidDecl()) {
10009 CorrectDelayedTyposInExpr(Init, dyn_cast_or_null<VarDecl>(RealDecl));
10013 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) {
10014 // Pure-specifiers are handled in ActOnPureSpecifier.
10015 Diag(Method->getLocation(), diag::err_member_function_initialization)
10016 << Method->getDeclName() << Init->getSourceRange();
10017 Method->setInvalidDecl();
10021 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl);
10023 assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here");
10024 Diag(RealDecl->getLocation(), diag::err_illegal_initializer);
10025 RealDecl->setInvalidDecl();
10029 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for.
10030 if (VDecl->getType()->isUndeducedType()) {
10031 // Attempt typo correction early so that the type of the init expression can
10032 // be deduced based on the chosen correction if the original init contains a
10034 ExprResult Res = CorrectDelayedTyposInExpr(Init, VDecl);
10035 if (!Res.isUsable()) {
10036 RealDecl->setInvalidDecl();
10041 if (DeduceVariableDeclarationType(VDecl, DirectInit, Init))
10045 // dllimport cannot be used on variable definitions.
10046 if (VDecl->hasAttr<DLLImportAttr>() && !VDecl->isStaticDataMember()) {
10047 Diag(VDecl->getLocation(), diag::err_attribute_dllimport_data_definition);
10048 VDecl->setInvalidDecl();
10052 if (VDecl->isLocalVarDecl() && VDecl->hasExternalStorage()) {
10053 // C99 6.7.8p5. C++ has no such restriction, but that is a defect.
10054 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init);
10055 VDecl->setInvalidDecl();
10059 if (!VDecl->getType()->isDependentType()) {
10060 // A definition must end up with a complete type, which means it must be
10061 // complete with the restriction that an array type might be completed by
10062 // the initializer; note that later code assumes this restriction.
10063 QualType BaseDeclType = VDecl->getType();
10064 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType))
10065 BaseDeclType = Array->getElementType();
10066 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType,
10067 diag::err_typecheck_decl_incomplete_type)) {
10068 RealDecl->setInvalidDecl();
10072 // The variable can not have an abstract class type.
10073 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(),
10074 diag::err_abstract_type_in_decl,
10075 AbstractVariableType))
10076 VDecl->setInvalidDecl();
10079 // If adding the initializer will turn this declaration into a definition,
10080 // and we already have a definition for this variable, diagnose or otherwise
10081 // handle the situation.
10083 if ((Def = VDecl->getDefinition()) && Def != VDecl &&
10084 (!VDecl->isStaticDataMember() || VDecl->isOutOfLine()) &&
10085 !VDecl->isThisDeclarationADemotedDefinition() &&
10086 checkVarDeclRedefinition(Def, VDecl))
10089 if (getLangOpts().CPlusPlus) {
10090 // C++ [class.static.data]p4
10091 // If a static data member is of const integral or const
10092 // enumeration type, its declaration in the class definition can
10093 // specify a constant-initializer which shall be an integral
10094 // constant expression (5.19). In that case, the member can appear
10095 // in integral constant expressions. The member shall still be
10096 // defined in a namespace scope if it is used in the program and the
10097 // namespace scope definition shall not contain an initializer.
10099 // We already performed a redefinition check above, but for static
10100 // data members we also need to check whether there was an in-class
10101 // declaration with an initializer.
10102 if (VDecl->isStaticDataMember() && VDecl->getCanonicalDecl()->hasInit()) {
10103 Diag(Init->getExprLoc(), diag::err_static_data_member_reinitialization)
10104 << VDecl->getDeclName();
10105 Diag(VDecl->getCanonicalDecl()->getInit()->getExprLoc(),
10106 diag::note_previous_initializer)
10111 if (VDecl->hasLocalStorage())
10112 getCurFunction()->setHasBranchProtectedScope();
10114 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) {
10115 VDecl->setInvalidDecl();
10120 // OpenCL 1.1 6.5.2: "Variables allocated in the __local address space inside
10121 // a kernel function cannot be initialized."
10122 if (VDecl->getType().getAddressSpace() == LangAS::opencl_local) {
10123 Diag(VDecl->getLocation(), diag::err_local_cant_init);
10124 VDecl->setInvalidDecl();
10128 // Get the decls type and save a reference for later, since
10129 // CheckInitializerTypes may change it.
10130 QualType DclT = VDecl->getType(), SavT = DclT;
10132 // Expressions default to 'id' when we're in a debugger
10133 // and we are assigning it to a variable of Objective-C pointer type.
10134 if (getLangOpts().DebuggerCastResultToId && DclT->isObjCObjectPointerType() &&
10135 Init->getType() == Context.UnknownAnyTy) {
10136 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
10137 if (Result.isInvalid()) {
10138 VDecl->setInvalidDecl();
10141 Init = Result.get();
10144 // Perform the initialization.
10145 ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
10146 if (!VDecl->isInvalidDecl()) {
10147 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
10148 InitializationKind Kind = InitializationKind::CreateForInit(
10149 VDecl->getLocation(), DirectInit, Init);
10151 MultiExprArg Args = Init;
10153 Args = MultiExprArg(CXXDirectInit->getExprs(),
10154 CXXDirectInit->getNumExprs());
10156 // Try to correct any TypoExprs in the initialization arguments.
10157 for (size_t Idx = 0; Idx < Args.size(); ++Idx) {
10158 ExprResult Res = CorrectDelayedTyposInExpr(
10159 Args[Idx], VDecl, [this, Entity, Kind](Expr *E) {
10160 InitializationSequence Init(*this, Entity, Kind, MultiExprArg(E));
10161 return Init.Failed() ? ExprError() : E;
10163 if (Res.isInvalid()) {
10164 VDecl->setInvalidDecl();
10165 } else if (Res.get() != Args[Idx]) {
10166 Args[Idx] = Res.get();
10169 if (VDecl->isInvalidDecl())
10172 InitializationSequence InitSeq(*this, Entity, Kind, Args,
10173 /*TopLevelOfInitList=*/false,
10174 /*TreatUnavailableAsInvalid=*/false);
10175 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
10176 if (Result.isInvalid()) {
10177 VDecl->setInvalidDecl();
10181 Init = Result.getAs<Expr>();
10184 // Check for self-references within variable initializers.
10185 // Variables declared within a function/method body (except for references)
10186 // are handled by a dataflow analysis.
10187 if (!VDecl->hasLocalStorage() || VDecl->getType()->isRecordType() ||
10188 VDecl->getType()->isReferenceType()) {
10189 CheckSelfReference(*this, RealDecl, Init, DirectInit);
10192 // If the type changed, it means we had an incomplete type that was
10193 // completed by the initializer. For example:
10194 // int ary[] = { 1, 3, 5 };
10195 // "ary" transitions from an IncompleteArrayType to a ConstantArrayType.
10196 if (!VDecl->isInvalidDecl() && (DclT != SavT))
10197 VDecl->setType(DclT);
10199 if (!VDecl->isInvalidDecl()) {
10200 checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init);
10202 if (VDecl->hasAttr<BlocksAttr>())
10203 checkRetainCycles(VDecl, Init);
10205 // It is safe to assign a weak reference into a strong variable.
10206 // Although this code can still have problems:
10207 // id x = self.weakProp;
10208 // id y = self.weakProp;
10209 // we do not warn to warn spuriously when 'x' and 'y' are on separate
10210 // paths through the function. This should be revisited if
10211 // -Wrepeated-use-of-weak is made flow-sensitive.
10212 if ((VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong ||
10213 VDecl->getType().isNonWeakInMRRWithObjCWeak(Context)) &&
10214 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
10215 Init->getLocStart()))
10216 getCurFunction()->markSafeWeakUse(Init);
10219 // The initialization is usually a full-expression.
10221 // FIXME: If this is a braced initialization of an aggregate, it is not
10222 // an expression, and each individual field initializer is a separate
10223 // full-expression. For instance, in:
10225 // struct Temp { ~Temp(); };
10226 // struct S { S(Temp); };
10227 // struct T { S a, b; } t = { Temp(), Temp() }
10229 // we should destroy the first Temp before constructing the second.
10230 ExprResult Result = ActOnFinishFullExpr(Init, VDecl->getLocation(),
10232 VDecl->isConstexpr());
10233 if (Result.isInvalid()) {
10234 VDecl->setInvalidDecl();
10237 Init = Result.get();
10239 // Attach the initializer to the decl.
10240 VDecl->setInit(Init);
10242 if (VDecl->isLocalVarDecl()) {
10243 // C99 6.7.8p4: All the expressions in an initializer for an object that has
10244 // static storage duration shall be constant expressions or string literals.
10245 // C++ does not have this restriction.
10246 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl()) {
10247 const Expr *Culprit;
10248 if (VDecl->getStorageClass() == SC_Static)
10249 CheckForConstantInitializer(Init, DclT);
10250 // C89 is stricter than C99 for non-static aggregate types.
10251 // C89 6.5.7p3: All the expressions [...] in an initializer list
10252 // for an object that has aggregate or union type shall be
10253 // constant expressions.
10254 else if (!getLangOpts().C99 && VDecl->getType()->isAggregateType() &&
10255 isa<InitListExpr>(Init) &&
10256 !Init->isConstantInitializer(Context, false, &Culprit))
10257 Diag(Culprit->getExprLoc(),
10258 diag::ext_aggregate_init_not_constant)
10259 << Culprit->getSourceRange();
10261 } else if (VDecl->isStaticDataMember() && !VDecl->isInline() &&
10262 VDecl->getLexicalDeclContext()->isRecord()) {
10263 // This is an in-class initialization for a static data member, e.g.,
10266 // static const int value = 17;
10269 // C++ [class.mem]p4:
10270 // A member-declarator can contain a constant-initializer only
10271 // if it declares a static member (9.4) of const integral or
10272 // const enumeration type, see 9.4.2.
10274 // C++11 [class.static.data]p3:
10275 // If a non-volatile non-inline const static data member is of integral
10276 // or enumeration type, its declaration in the class definition can
10277 // specify a brace-or-equal-initializer in which every initializer-clause
10278 // that is an assignment-expression is a constant expression. A static
10279 // data member of literal type can be declared in the class definition
10280 // with the constexpr specifier; if so, its declaration shall specify a
10281 // brace-or-equal-initializer in which every initializer-clause that is
10282 // an assignment-expression is a constant expression.
10284 // Do nothing on dependent types.
10285 if (DclT->isDependentType()) {
10287 // Allow any 'static constexpr' members, whether or not they are of literal
10288 // type. We separately check that every constexpr variable is of literal
10290 } else if (VDecl->isConstexpr()) {
10292 // Require constness.
10293 } else if (!DclT.isConstQualified()) {
10294 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const)
10295 << Init->getSourceRange();
10296 VDecl->setInvalidDecl();
10298 // We allow integer constant expressions in all cases.
10299 } else if (DclT->isIntegralOrEnumerationType()) {
10300 // Check whether the expression is a constant expression.
10301 SourceLocation Loc;
10302 if (getLangOpts().CPlusPlus11 && DclT.isVolatileQualified())
10303 // In C++11, a non-constexpr const static data member with an
10304 // in-class initializer cannot be volatile.
10305 Diag(VDecl->getLocation(), diag::err_in_class_initializer_volatile);
10306 else if (Init->isValueDependent())
10307 ; // Nothing to check.
10308 else if (Init->isIntegerConstantExpr(Context, &Loc))
10309 ; // Ok, it's an ICE!
10310 else if (Init->isEvaluatable(Context)) {
10311 // If we can constant fold the initializer through heroics, accept it,
10312 // but report this as a use of an extension for -pedantic.
10313 Diag(Loc, diag::ext_in_class_initializer_non_constant)
10314 << Init->getSourceRange();
10316 // Otherwise, this is some crazy unknown case. Report the issue at the
10317 // location provided by the isIntegerConstantExpr failed check.
10318 Diag(Loc, diag::err_in_class_initializer_non_constant)
10319 << Init->getSourceRange();
10320 VDecl->setInvalidDecl();
10323 // We allow foldable floating-point constants as an extension.
10324 } else if (DclT->isFloatingType()) { // also permits complex, which is ok
10325 // In C++98, this is a GNU extension. In C++11, it is not, but we support
10326 // it anyway and provide a fixit to add the 'constexpr'.
10327 if (getLangOpts().CPlusPlus11) {
10328 Diag(VDecl->getLocation(),
10329 diag::ext_in_class_initializer_float_type_cxx11)
10330 << DclT << Init->getSourceRange();
10331 Diag(VDecl->getLocStart(),
10332 diag::note_in_class_initializer_float_type_cxx11)
10333 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
10335 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type)
10336 << DclT << Init->getSourceRange();
10338 if (!Init->isValueDependent() && !Init->isEvaluatable(Context)) {
10339 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant)
10340 << Init->getSourceRange();
10341 VDecl->setInvalidDecl();
10345 // Suggest adding 'constexpr' in C++11 for literal types.
10346 } else if (getLangOpts().CPlusPlus11 && DclT->isLiteralType(Context)) {
10347 Diag(VDecl->getLocation(), diag::err_in_class_initializer_literal_type)
10348 << DclT << Init->getSourceRange()
10349 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
10350 VDecl->setConstexpr(true);
10353 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type)
10354 << DclT << Init->getSourceRange();
10355 VDecl->setInvalidDecl();
10357 } else if (VDecl->isFileVarDecl()) {
10358 // In C, extern is typically used to avoid tentative definitions when
10359 // declaring variables in headers, but adding an intializer makes it a
10360 // defintion. This is somewhat confusing, so GCC and Clang both warn on it.
10361 // In C++, extern is often used to give implictly static const variables
10362 // external linkage, so don't warn in that case. If selectany is present,
10363 // this might be header code intended for C and C++ inclusion, so apply the
10365 if (VDecl->getStorageClass() == SC_Extern &&
10366 ((!getLangOpts().CPlusPlus && !VDecl->hasAttr<SelectAnyAttr>()) ||
10367 !Context.getBaseElementType(VDecl->getType()).isConstQualified()) &&
10368 !(getLangOpts().CPlusPlus && VDecl->isExternC()) &&
10369 !isTemplateInstantiation(VDecl->getTemplateSpecializationKind()))
10370 Diag(VDecl->getLocation(), diag::warn_extern_init);
10372 // C99 6.7.8p4. All file scoped initializers need to be constant.
10373 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl())
10374 CheckForConstantInitializer(Init, DclT);
10377 // We will represent direct-initialization similarly to copy-initialization:
10378 // int x(1); -as-> int x = 1;
10379 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c);
10381 // Clients that want to distinguish between the two forms, can check for
10382 // direct initializer using VarDecl::getInitStyle().
10383 // A major benefit is that clients that don't particularly care about which
10384 // exactly form was it (like the CodeGen) can handle both cases without
10385 // special case code.
10388 // The form of initialization (using parentheses or '=') is generally
10389 // insignificant, but does matter when the entity being initialized has a
10391 if (CXXDirectInit) {
10392 assert(DirectInit && "Call-style initializer must be direct init.");
10393 VDecl->setInitStyle(VarDecl::CallInit);
10394 } else if (DirectInit) {
10395 // This must be list-initialization. No other way is direct-initialization.
10396 VDecl->setInitStyle(VarDecl::ListInit);
10399 CheckCompleteVariableDeclaration(VDecl);
10402 /// ActOnInitializerError - Given that there was an error parsing an
10403 /// initializer for the given declaration, try to return to some form
10405 void Sema::ActOnInitializerError(Decl *D) {
10406 // Our main concern here is re-establishing invariants like "a
10407 // variable's type is either dependent or complete".
10408 if (!D || D->isInvalidDecl()) return;
10410 VarDecl *VD = dyn_cast<VarDecl>(D);
10413 // Bindings are not usable if we can't make sense of the initializer.
10414 if (auto *DD = dyn_cast<DecompositionDecl>(D))
10415 for (auto *BD : DD->bindings())
10416 BD->setInvalidDecl();
10418 // Auto types are meaningless if we can't make sense of the initializer.
10419 if (ParsingInitForAutoVars.count(D)) {
10420 D->setInvalidDecl();
10424 QualType Ty = VD->getType();
10425 if (Ty->isDependentType()) return;
10427 // Require a complete type.
10428 if (RequireCompleteType(VD->getLocation(),
10429 Context.getBaseElementType(Ty),
10430 diag::err_typecheck_decl_incomplete_type)) {
10431 VD->setInvalidDecl();
10435 // Require a non-abstract type.
10436 if (RequireNonAbstractType(VD->getLocation(), Ty,
10437 diag::err_abstract_type_in_decl,
10438 AbstractVariableType)) {
10439 VD->setInvalidDecl();
10443 // Don't bother complaining about constructors or destructors,
10447 void Sema::ActOnUninitializedDecl(Decl *RealDecl) {
10448 // If there is no declaration, there was an error parsing it. Just ignore it.
10452 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) {
10453 QualType Type = Var->getType();
10455 // C++1z [dcl.dcl]p1 grammar implies that an initializer is mandatory.
10456 if (isa<DecompositionDecl>(RealDecl)) {
10457 Diag(Var->getLocation(), diag::err_decomp_decl_requires_init) << Var;
10458 Var->setInvalidDecl();
10462 if (Type->isUndeducedType() &&
10463 DeduceVariableDeclarationType(Var, false, nullptr))
10466 // C++11 [class.static.data]p3: A static data member can be declared with
10467 // the constexpr specifier; if so, its declaration shall specify
10468 // a brace-or-equal-initializer.
10469 // C++11 [dcl.constexpr]p1: The constexpr specifier shall be applied only to
10470 // the definition of a variable [...] or the declaration of a static data
10472 if (Var->isConstexpr() && !Var->isThisDeclarationADefinition() &&
10473 !Var->isThisDeclarationADemotedDefinition()) {
10474 if (Var->isStaticDataMember()) {
10475 // C++1z removes the relevant rule; the in-class declaration is always
10476 // a definition there.
10477 if (!getLangOpts().CPlusPlus1z) {
10478 Diag(Var->getLocation(),
10479 diag::err_constexpr_static_mem_var_requires_init)
10480 << Var->getDeclName();
10481 Var->setInvalidDecl();
10485 Diag(Var->getLocation(), diag::err_invalid_constexpr_var_decl);
10486 Var->setInvalidDecl();
10491 // C++ Concepts TS [dcl.spec.concept]p1: [...] A variable template
10492 // definition having the concept specifier is called a variable concept. A
10493 // concept definition refers to [...] a variable concept and its initializer.
10494 if (VarTemplateDecl *VTD = Var->getDescribedVarTemplate()) {
10495 if (VTD->isConcept()) {
10496 Diag(Var->getLocation(), diag::err_var_concept_not_initialized);
10497 Var->setInvalidDecl();
10502 // OpenCL v1.1 s6.5.3: variables declared in the constant address space must
10504 if (!Var->isInvalidDecl() &&
10505 Var->getType().getAddressSpace() == LangAS::opencl_constant &&
10506 Var->getStorageClass() != SC_Extern && !Var->getInit()) {
10507 Diag(Var->getLocation(), diag::err_opencl_constant_no_init);
10508 Var->setInvalidDecl();
10512 switch (Var->isThisDeclarationADefinition()) {
10513 case VarDecl::Definition:
10514 if (!Var->isStaticDataMember() || !Var->getAnyInitializer())
10517 // We have an out-of-line definition of a static data member
10518 // that has an in-class initializer, so we type-check this like
10523 case VarDecl::DeclarationOnly:
10524 // It's only a declaration.
10526 // Block scope. C99 6.7p7: If an identifier for an object is
10527 // declared with no linkage (C99 6.2.2p6), the type for the
10528 // object shall be complete.
10529 if (!Type->isDependentType() && Var->isLocalVarDecl() &&
10530 !Var->hasLinkage() && !Var->isInvalidDecl() &&
10531 RequireCompleteType(Var->getLocation(), Type,
10532 diag::err_typecheck_decl_incomplete_type))
10533 Var->setInvalidDecl();
10535 // Make sure that the type is not abstract.
10536 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
10537 RequireNonAbstractType(Var->getLocation(), Type,
10538 diag::err_abstract_type_in_decl,
10539 AbstractVariableType))
10540 Var->setInvalidDecl();
10541 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
10542 Var->getStorageClass() == SC_PrivateExtern) {
10543 Diag(Var->getLocation(), diag::warn_private_extern);
10544 Diag(Var->getLocation(), diag::note_private_extern);
10549 case VarDecl::TentativeDefinition:
10550 // File scope. C99 6.9.2p2: A declaration of an identifier for an
10551 // object that has file scope without an initializer, and without a
10552 // storage-class specifier or with the storage-class specifier "static",
10553 // constitutes a tentative definition. Note: A tentative definition with
10554 // external linkage is valid (C99 6.2.2p5).
10555 if (!Var->isInvalidDecl()) {
10556 if (const IncompleteArrayType *ArrayT
10557 = Context.getAsIncompleteArrayType(Type)) {
10558 if (RequireCompleteType(Var->getLocation(),
10559 ArrayT->getElementType(),
10560 diag::err_illegal_decl_array_incomplete_type))
10561 Var->setInvalidDecl();
10562 } else if (Var->getStorageClass() == SC_Static) {
10563 // C99 6.9.2p3: If the declaration of an identifier for an object is
10564 // a tentative definition and has internal linkage (C99 6.2.2p3), the
10565 // declared type shall not be an incomplete type.
10566 // NOTE: code such as the following
10567 // static struct s;
10568 // struct s { int a; };
10569 // is accepted by gcc. Hence here we issue a warning instead of
10570 // an error and we do not invalidate the static declaration.
10571 // NOTE: to avoid multiple warnings, only check the first declaration.
10572 if (Var->isFirstDecl())
10573 RequireCompleteType(Var->getLocation(), Type,
10574 diag::ext_typecheck_decl_incomplete_type);
10578 // Record the tentative definition; we're done.
10579 if (!Var->isInvalidDecl())
10580 TentativeDefinitions.push_back(Var);
10584 // Provide a specific diagnostic for uninitialized variable
10585 // definitions with incomplete array type.
10586 if (Type->isIncompleteArrayType()) {
10587 Diag(Var->getLocation(),
10588 diag::err_typecheck_incomplete_array_needs_initializer);
10589 Var->setInvalidDecl();
10593 // Provide a specific diagnostic for uninitialized variable
10594 // definitions with reference type.
10595 if (Type->isReferenceType()) {
10596 Diag(Var->getLocation(), diag::err_reference_var_requires_init)
10597 << Var->getDeclName()
10598 << SourceRange(Var->getLocation(), Var->getLocation());
10599 Var->setInvalidDecl();
10603 // Do not attempt to type-check the default initializer for a
10604 // variable with dependent type.
10605 if (Type->isDependentType())
10608 if (Var->isInvalidDecl())
10611 if (!Var->hasAttr<AliasAttr>()) {
10612 if (RequireCompleteType(Var->getLocation(),
10613 Context.getBaseElementType(Type),
10614 diag::err_typecheck_decl_incomplete_type)) {
10615 Var->setInvalidDecl();
10622 // The variable can not have an abstract class type.
10623 if (RequireNonAbstractType(Var->getLocation(), Type,
10624 diag::err_abstract_type_in_decl,
10625 AbstractVariableType)) {
10626 Var->setInvalidDecl();
10630 // Check for jumps past the implicit initializer. C++0x
10631 // clarifies that this applies to a "variable with automatic
10632 // storage duration", not a "local variable".
10633 // C++11 [stmt.dcl]p3
10634 // A program that jumps from a point where a variable with automatic
10635 // storage duration is not in scope to a point where it is in scope is
10636 // ill-formed unless the variable has scalar type, class type with a
10637 // trivial default constructor and a trivial destructor, a cv-qualified
10638 // version of one of these types, or an array of one of the preceding
10639 // types and is declared without an initializer.
10640 if (getLangOpts().CPlusPlus && Var->hasLocalStorage()) {
10641 if (const RecordType *Record
10642 = Context.getBaseElementType(Type)->getAs<RecordType>()) {
10643 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl());
10644 // Mark the function for further checking even if the looser rules of
10645 // C++11 do not require such checks, so that we can diagnose
10646 // incompatibilities with C++98.
10647 if (!CXXRecord->isPOD())
10648 getCurFunction()->setHasBranchProtectedScope();
10652 // C++03 [dcl.init]p9:
10653 // If no initializer is specified for an object, and the
10654 // object is of (possibly cv-qualified) non-POD class type (or
10655 // array thereof), the object shall be default-initialized; if
10656 // the object is of const-qualified type, the underlying class
10657 // type shall have a user-declared default
10658 // constructor. Otherwise, if no initializer is specified for
10659 // a non- static object, the object and its subobjects, if
10660 // any, have an indeterminate initial value); if the object
10661 // or any of its subobjects are of const-qualified type, the
10662 // program is ill-formed.
10663 // C++0x [dcl.init]p11:
10664 // If no initializer is specified for an object, the object is
10665 // default-initialized; [...].
10666 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var);
10667 InitializationKind Kind
10668 = InitializationKind::CreateDefault(Var->getLocation());
10670 InitializationSequence InitSeq(*this, Entity, Kind, None);
10671 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, None);
10672 if (Init.isInvalid())
10673 Var->setInvalidDecl();
10674 else if (Init.get()) {
10675 Var->setInit(MaybeCreateExprWithCleanups(Init.get()));
10676 // This is important for template substitution.
10677 Var->setInitStyle(VarDecl::CallInit);
10680 CheckCompleteVariableDeclaration(Var);
10684 void Sema::ActOnCXXForRangeDecl(Decl *D) {
10685 // If there is no declaration, there was an error parsing it. Ignore it.
10689 VarDecl *VD = dyn_cast<VarDecl>(D);
10691 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var);
10692 D->setInvalidDecl();
10696 VD->setCXXForRangeDecl(true);
10698 // for-range-declaration cannot be given a storage class specifier.
10700 switch (VD->getStorageClass()) {
10709 case SC_PrivateExtern:
10720 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class)
10721 << VD->getDeclName() << Error;
10722 D->setInvalidDecl();
10727 Sema::ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
10728 IdentifierInfo *Ident,
10729 ParsedAttributes &Attrs,
10730 SourceLocation AttrEnd) {
10731 // C++1y [stmt.iter]p1:
10732 // A range-based for statement of the form
10733 // for ( for-range-identifier : for-range-initializer ) statement
10734 // is equivalent to
10735 // for ( auto&& for-range-identifier : for-range-initializer ) statement
10736 DeclSpec DS(Attrs.getPool().getFactory());
10738 const char *PrevSpec;
10740 DS.SetTypeSpecType(DeclSpec::TST_auto, IdentLoc, PrevSpec, DiagID,
10741 getPrintingPolicy());
10743 Declarator D(DS, Declarator::ForContext);
10744 D.SetIdentifier(Ident, IdentLoc);
10745 D.takeAttributes(Attrs, AttrEnd);
10747 ParsedAttributes EmptyAttrs(Attrs.getPool().getFactory());
10748 D.AddTypeInfo(DeclaratorChunk::getReference(0, IdentLoc, /*lvalue*/false),
10749 EmptyAttrs, IdentLoc);
10750 Decl *Var = ActOnDeclarator(S, D);
10751 cast<VarDecl>(Var)->setCXXForRangeDecl(true);
10752 FinalizeDeclaration(Var);
10753 return ActOnDeclStmt(FinalizeDeclaratorGroup(S, DS, Var), IdentLoc,
10754 AttrEnd.isValid() ? AttrEnd : IdentLoc);
10757 void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
10758 if (var->isInvalidDecl()) return;
10760 if (getLangOpts().OpenCL) {
10761 // OpenCL v2.0 s6.12.5 - Every block variable declaration must have an
10763 if (var->getTypeSourceInfo()->getType()->isBlockPointerType() &&
10765 Diag(var->getLocation(), diag::err_opencl_invalid_block_declaration)
10767 var->setInvalidDecl();
10772 // In Objective-C, don't allow jumps past the implicit initialization of a
10773 // local retaining variable.
10774 if (getLangOpts().ObjC1 &&
10775 var->hasLocalStorage()) {
10776 switch (var->getType().getObjCLifetime()) {
10777 case Qualifiers::OCL_None:
10778 case Qualifiers::OCL_ExplicitNone:
10779 case Qualifiers::OCL_Autoreleasing:
10782 case Qualifiers::OCL_Weak:
10783 case Qualifiers::OCL_Strong:
10784 getCurFunction()->setHasBranchProtectedScope();
10789 // Warn about externally-visible variables being defined without a
10790 // prior declaration. We only want to do this for global
10791 // declarations, but we also specifically need to avoid doing it for
10792 // class members because the linkage of an anonymous class can
10793 // change if it's later given a typedef name.
10794 if (var->isThisDeclarationADefinition() &&
10795 var->getDeclContext()->getRedeclContext()->isFileContext() &&
10796 var->isExternallyVisible() && var->hasLinkage() &&
10797 !getDiagnostics().isIgnored(diag::warn_missing_variable_declarations,
10798 var->getLocation())) {
10799 // Find a previous declaration that's not a definition.
10800 VarDecl *prev = var->getPreviousDecl();
10801 while (prev && prev->isThisDeclarationADefinition())
10802 prev = prev->getPreviousDecl();
10805 Diag(var->getLocation(), diag::warn_missing_variable_declarations) << var;
10808 // Cache the result of checking for constant initialization.
10809 Optional<bool> CacheHasConstInit;
10810 const Expr *CacheCulprit;
10811 auto checkConstInit = [&]() mutable {
10812 if (!CacheHasConstInit)
10813 CacheHasConstInit = var->getInit()->isConstantInitializer(
10814 Context, var->getType()->isReferenceType(), &CacheCulprit);
10815 return *CacheHasConstInit;
10818 if (var->getTLSKind() == VarDecl::TLS_Static) {
10819 if (var->getType().isDestructedType()) {
10820 // GNU C++98 edits for __thread, [basic.start.term]p3:
10821 // The type of an object with thread storage duration shall not
10822 // have a non-trivial destructor.
10823 Diag(var->getLocation(), diag::err_thread_nontrivial_dtor);
10824 if (getLangOpts().CPlusPlus11)
10825 Diag(var->getLocation(), diag::note_use_thread_local);
10826 } else if (getLangOpts().CPlusPlus && var->hasInit()) {
10827 if (!checkConstInit()) {
10828 // GNU C++98 edits for __thread, [basic.start.init]p4:
10829 // An object of thread storage duration shall not require dynamic
10831 // FIXME: Need strict checking here.
10832 Diag(CacheCulprit->getExprLoc(), diag::err_thread_dynamic_init)
10833 << CacheCulprit->getSourceRange();
10834 if (getLangOpts().CPlusPlus11)
10835 Diag(var->getLocation(), diag::note_use_thread_local);
10840 // Apply section attributes and pragmas to global variables.
10841 bool GlobalStorage = var->hasGlobalStorage();
10842 if (GlobalStorage && var->isThisDeclarationADefinition() &&
10843 !inTemplateInstantiation()) {
10844 PragmaStack<StringLiteral *> *Stack = nullptr;
10845 int SectionFlags = ASTContext::PSF_Implicit | ASTContext::PSF_Read;
10846 if (var->getType().isConstQualified())
10847 Stack = &ConstSegStack;
10848 else if (!var->getInit()) {
10849 Stack = &BSSSegStack;
10850 SectionFlags |= ASTContext::PSF_Write;
10852 Stack = &DataSegStack;
10853 SectionFlags |= ASTContext::PSF_Write;
10855 if (Stack->CurrentValue && !var->hasAttr<SectionAttr>()) {
10856 var->addAttr(SectionAttr::CreateImplicit(
10857 Context, SectionAttr::Declspec_allocate,
10858 Stack->CurrentValue->getString(), Stack->CurrentPragmaLocation));
10860 if (const SectionAttr *SA = var->getAttr<SectionAttr>())
10861 if (UnifySection(SA->getName(), SectionFlags, var))
10862 var->dropAttr<SectionAttr>();
10864 // Apply the init_seg attribute if this has an initializer. If the
10865 // initializer turns out to not be dynamic, we'll end up ignoring this
10867 if (CurInitSeg && var->getInit())
10868 var->addAttr(InitSegAttr::CreateImplicit(Context, CurInitSeg->getString(),
10872 // All the following checks are C++ only.
10873 if (!getLangOpts().CPlusPlus) {
10874 // If this variable must be emitted, add it as an initializer for the
10876 if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
10877 Context.addModuleInitializer(ModuleScopes.back().Module, var);
10881 if (auto *DD = dyn_cast<DecompositionDecl>(var))
10882 CheckCompleteDecompositionDeclaration(DD);
10884 QualType type = var->getType();
10885 if (type->isDependentType()) return;
10887 // __block variables might require us to capture a copy-initializer.
10888 if (var->hasAttr<BlocksAttr>()) {
10889 // It's currently invalid to ever have a __block variable with an
10890 // array type; should we diagnose that here?
10892 // Regardless, we don't want to ignore array nesting when
10893 // constructing this copy.
10894 if (type->isStructureOrClassType()) {
10895 EnterExpressionEvaluationContext scope(
10896 *this, ExpressionEvaluationContext::PotentiallyEvaluated);
10897 SourceLocation poi = var->getLocation();
10898 Expr *varRef =new (Context) DeclRefExpr(var, false, type, VK_LValue, poi);
10900 = PerformMoveOrCopyInitialization(
10901 InitializedEntity::InitializeBlock(poi, type, false),
10902 var, var->getType(), varRef, /*AllowNRVO=*/true);
10903 if (!result.isInvalid()) {
10904 result = MaybeCreateExprWithCleanups(result);
10905 Expr *init = result.getAs<Expr>();
10906 Context.setBlockVarCopyInits(var, init);
10911 Expr *Init = var->getInit();
10912 bool IsGlobal = GlobalStorage && !var->isStaticLocal();
10913 QualType baseType = Context.getBaseElementType(type);
10915 if (!var->getDeclContext()->isDependentContext() &&
10916 Init && !Init->isValueDependent()) {
10918 if (var->isConstexpr()) {
10919 SmallVector<PartialDiagnosticAt, 8> Notes;
10920 if (!var->evaluateValue(Notes) || !var->isInitICE()) {
10921 SourceLocation DiagLoc = var->getLocation();
10922 // If the note doesn't add any useful information other than a source
10923 // location, fold it into the primary diagnostic.
10924 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
10925 diag::note_invalid_subexpr_in_const_expr) {
10926 DiagLoc = Notes[0].first;
10929 Diag(DiagLoc, diag::err_constexpr_var_requires_const_init)
10930 << var << Init->getSourceRange();
10931 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
10932 Diag(Notes[I].first, Notes[I].second);
10934 } else if (var->isUsableInConstantExpressions(Context)) {
10935 // Check whether the initializer of a const variable of integral or
10936 // enumeration type is an ICE now, since we can't tell whether it was
10937 // initialized by a constant expression if we check later.
10938 var->checkInitIsICE();
10941 // Don't emit further diagnostics about constexpr globals since they
10942 // were just diagnosed.
10943 if (!var->isConstexpr() && GlobalStorage &&
10944 var->hasAttr<RequireConstantInitAttr>()) {
10945 // FIXME: Need strict checking in C++03 here.
10946 bool DiagErr = getLangOpts().CPlusPlus11
10947 ? !var->checkInitIsICE() : !checkConstInit();
10949 auto attr = var->getAttr<RequireConstantInitAttr>();
10950 Diag(var->getLocation(), diag::err_require_constant_init_failed)
10951 << Init->getSourceRange();
10952 Diag(attr->getLocation(), diag::note_declared_required_constant_init_here)
10953 << attr->getRange();
10956 else if (!var->isConstexpr() && IsGlobal &&
10957 !getDiagnostics().isIgnored(diag::warn_global_constructor,
10958 var->getLocation())) {
10959 // Warn about globals which don't have a constant initializer. Don't
10960 // warn about globals with a non-trivial destructor because we already
10961 // warned about them.
10962 CXXRecordDecl *RD = baseType->getAsCXXRecordDecl();
10963 if (!(RD && !RD->hasTrivialDestructor())) {
10964 if (!checkConstInit())
10965 Diag(var->getLocation(), diag::warn_global_constructor)
10966 << Init->getSourceRange();
10971 // Require the destructor.
10972 if (const RecordType *recordType = baseType->getAs<RecordType>())
10973 FinalizeVarWithDestructor(var, recordType);
10975 // If this variable must be emitted, add it as an initializer for the current
10977 if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
10978 Context.addModuleInitializer(ModuleScopes.back().Module, var);
10981 /// \brief Determines if a variable's alignment is dependent.
10982 static bool hasDependentAlignment(VarDecl *VD) {
10983 if (VD->getType()->isDependentType())
10985 for (auto *I : VD->specific_attrs<AlignedAttr>())
10986 if (I->isAlignmentDependent())
10991 /// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform
10992 /// any semantic actions necessary after any initializer has been attached.
10994 Sema::FinalizeDeclaration(Decl *ThisDecl) {
10995 // Note that we are no longer parsing the initializer for this declaration.
10996 ParsingInitForAutoVars.erase(ThisDecl);
10998 VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDecl);
11002 if (auto *DD = dyn_cast<DecompositionDecl>(ThisDecl)) {
11003 for (auto *BD : DD->bindings()) {
11004 FinalizeDeclaration(BD);
11008 checkAttributesAfterMerging(*this, *VD);
11010 // Perform TLS alignment check here after attributes attached to the variable
11011 // which may affect the alignment have been processed. Only perform the check
11012 // if the target has a maximum TLS alignment (zero means no constraints).
11013 if (unsigned MaxAlign = Context.getTargetInfo().getMaxTLSAlign()) {
11014 // Protect the check so that it's not performed on dependent types and
11015 // dependent alignments (we can't determine the alignment in that case).
11016 if (VD->getTLSKind() && !hasDependentAlignment(VD) &&
11017 !VD->isInvalidDecl()) {
11018 CharUnits MaxAlignChars = Context.toCharUnitsFromBits(MaxAlign);
11019 if (Context.getDeclAlign(VD) > MaxAlignChars) {
11020 Diag(VD->getLocation(), diag::err_tls_var_aligned_over_maximum)
11021 << (unsigned)Context.getDeclAlign(VD).getQuantity() << VD
11022 << (unsigned)MaxAlignChars.getQuantity();
11027 if (VD->isStaticLocal()) {
11028 if (FunctionDecl *FD =
11029 dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod())) {
11030 // Static locals inherit dll attributes from their function.
11031 if (Attr *A = getDLLAttr(FD)) {
11032 auto *NewAttr = cast<InheritableAttr>(A->clone(getASTContext()));
11033 NewAttr->setInherited(true);
11034 VD->addAttr(NewAttr);
11036 // CUDA E.2.9.4: Within the body of a __device__ or __global__
11037 // function, only __shared__ variables may be declared with
11038 // static storage class.
11039 if (getLangOpts().CUDA && !VD->hasAttr<CUDASharedAttr>() &&
11040 CUDADiagIfDeviceCode(VD->getLocation(),
11041 diag::err_device_static_local_var)
11042 << CurrentCUDATarget())
11043 VD->setInvalidDecl();
11047 // Perform check for initializers of device-side global variables.
11048 // CUDA allows empty constructors as initializers (see E.2.3.1, CUDA
11049 // 7.5). We must also apply the same checks to all __shared__
11050 // variables whether they are local or not. CUDA also allows
11051 // constant initializers for __constant__ and __device__ variables.
11052 if (getLangOpts().CUDA) {
11053 const Expr *Init = VD->getInit();
11054 if (Init && VD->hasGlobalStorage()) {
11055 if (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>() ||
11056 VD->hasAttr<CUDASharedAttr>()) {
11057 assert(!VD->isStaticLocal() || VD->hasAttr<CUDASharedAttr>());
11058 bool AllowedInit = false;
11059 if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(Init))
11061 isEmptyCudaConstructor(VD->getLocation(), CE->getConstructor());
11062 // We'll allow constant initializers even if it's a non-empty
11063 // constructor according to CUDA rules. This deviates from NVCC,
11064 // but allows us to handle things like constexpr constructors.
11065 if (!AllowedInit &&
11066 (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>()))
11067 AllowedInit = VD->getInit()->isConstantInitializer(
11068 Context, VD->getType()->isReferenceType());
11070 // Also make sure that destructor, if there is one, is empty.
11072 if (CXXRecordDecl *RD = VD->getType()->getAsCXXRecordDecl())
11074 isEmptyCudaDestructor(VD->getLocation(), RD->getDestructor());
11076 if (!AllowedInit) {
11077 Diag(VD->getLocation(), VD->hasAttr<CUDASharedAttr>()
11078 ? diag::err_shared_var_init
11079 : diag::err_dynamic_var_init)
11080 << Init->getSourceRange();
11081 VD->setInvalidDecl();
11084 // This is a host-side global variable. Check that the initializer is
11085 // callable from the host side.
11086 const FunctionDecl *InitFn = nullptr;
11087 if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(Init)) {
11088 InitFn = CE->getConstructor();
11089 } else if (const CallExpr *CE = dyn_cast<CallExpr>(Init)) {
11090 InitFn = CE->getDirectCallee();
11093 CUDAFunctionTarget InitFnTarget = IdentifyCUDATarget(InitFn);
11094 if (InitFnTarget != CFT_Host && InitFnTarget != CFT_HostDevice) {
11095 Diag(VD->getLocation(), diag::err_ref_bad_target_global_initializer)
11096 << InitFnTarget << InitFn;
11097 Diag(InitFn->getLocation(), diag::note_previous_decl) << InitFn;
11098 VD->setInvalidDecl();
11105 // Grab the dllimport or dllexport attribute off of the VarDecl.
11106 const InheritableAttr *DLLAttr = getDLLAttr(VD);
11108 // Imported static data members cannot be defined out-of-line.
11109 if (const auto *IA = dyn_cast_or_null<DLLImportAttr>(DLLAttr)) {
11110 if (VD->isStaticDataMember() && VD->isOutOfLine() &&
11111 VD->isThisDeclarationADefinition()) {
11112 // We allow definitions of dllimport class template static data members
11114 CXXRecordDecl *Context =
11115 cast<CXXRecordDecl>(VD->getFirstDecl()->getDeclContext());
11116 bool IsClassTemplateMember =
11117 isa<ClassTemplatePartialSpecializationDecl>(Context) ||
11118 Context->getDescribedClassTemplate();
11120 Diag(VD->getLocation(),
11121 IsClassTemplateMember
11122 ? diag::warn_attribute_dllimport_static_field_definition
11123 : diag::err_attribute_dllimport_static_field_definition);
11124 Diag(IA->getLocation(), diag::note_attribute);
11125 if (!IsClassTemplateMember)
11126 VD->setInvalidDecl();
11130 // dllimport/dllexport variables cannot be thread local, their TLS index
11131 // isn't exported with the variable.
11132 if (DLLAttr && VD->getTLSKind()) {
11133 auto *F = dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod());
11134 if (F && getDLLAttr(F)) {
11135 assert(VD->isStaticLocal());
11136 // But if this is a static local in a dlimport/dllexport function, the
11137 // function will never be inlined, which means the var would never be
11138 // imported, so having it marked import/export is safe.
11140 Diag(VD->getLocation(), diag::err_attribute_dll_thread_local) << VD
11142 VD->setInvalidDecl();
11146 if (UsedAttr *Attr = VD->getAttr<UsedAttr>()) {
11147 if (!Attr->isInherited() && !VD->isThisDeclarationADefinition()) {
11148 Diag(Attr->getLocation(), diag::warn_attribute_ignored) << Attr;
11149 VD->dropAttr<UsedAttr>();
11153 const DeclContext *DC = VD->getDeclContext();
11154 // If there's a #pragma GCC visibility in scope, and this isn't a class
11155 // member, set the visibility of this variable.
11156 if (DC->getRedeclContext()->isFileContext() && VD->isExternallyVisible())
11157 AddPushedVisibilityAttribute(VD);
11159 // FIXME: Warn on unused templates.
11160 if (VD->isFileVarDecl() && !VD->getDescribedVarTemplate() &&
11161 !isa<VarTemplatePartialSpecializationDecl>(VD))
11162 MarkUnusedFileScopedDecl(VD);
11164 // Now we have parsed the initializer and can update the table of magic
11166 if (!VD->hasAttr<TypeTagForDatatypeAttr>() ||
11167 !VD->getType()->isIntegralOrEnumerationType())
11170 for (const auto *I : ThisDecl->specific_attrs<TypeTagForDatatypeAttr>()) {
11171 const Expr *MagicValueExpr = VD->getInit();
11172 if (!MagicValueExpr) {
11175 llvm::APSInt MagicValueInt;
11176 if (!MagicValueExpr->isIntegerConstantExpr(MagicValueInt, Context)) {
11177 Diag(I->getRange().getBegin(),
11178 diag::err_type_tag_for_datatype_not_ice)
11179 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
11182 if (MagicValueInt.getActiveBits() > 64) {
11183 Diag(I->getRange().getBegin(),
11184 diag::err_type_tag_for_datatype_too_large)
11185 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
11188 uint64_t MagicValue = MagicValueInt.getZExtValue();
11189 RegisterTypeTagForDatatype(I->getArgumentKind(),
11191 I->getMatchingCType(),
11192 I->getLayoutCompatible(),
11193 I->getMustBeNull());
11197 static bool hasDeducedAuto(DeclaratorDecl *DD) {
11198 auto *VD = dyn_cast<VarDecl>(DD);
11199 return VD && !VD->getType()->hasAutoForTrailingReturnType();
11202 Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
11203 ArrayRef<Decl *> Group) {
11204 SmallVector<Decl*, 8> Decls;
11206 if (DS.isTypeSpecOwned())
11207 Decls.push_back(DS.getRepAsDecl());
11209 DeclaratorDecl *FirstDeclaratorInGroup = nullptr;
11210 DecompositionDecl *FirstDecompDeclaratorInGroup = nullptr;
11211 bool DiagnosedMultipleDecomps = false;
11212 DeclaratorDecl *FirstNonDeducedAutoInGroup = nullptr;
11213 bool DiagnosedNonDeducedAuto = false;
11215 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
11216 if (Decl *D = Group[i]) {
11217 // For declarators, there are some additional syntactic-ish checks we need
11219 if (auto *DD = dyn_cast<DeclaratorDecl>(D)) {
11220 if (!FirstDeclaratorInGroup)
11221 FirstDeclaratorInGroup = DD;
11222 if (!FirstDecompDeclaratorInGroup)
11223 FirstDecompDeclaratorInGroup = dyn_cast<DecompositionDecl>(D);
11224 if (!FirstNonDeducedAutoInGroup && DS.hasAutoTypeSpec() &&
11225 !hasDeducedAuto(DD))
11226 FirstNonDeducedAutoInGroup = DD;
11228 if (FirstDeclaratorInGroup != DD) {
11229 // A decomposition declaration cannot be combined with any other
11230 // declaration in the same group.
11231 if (FirstDecompDeclaratorInGroup && !DiagnosedMultipleDecomps) {
11232 Diag(FirstDecompDeclaratorInGroup->getLocation(),
11233 diag::err_decomp_decl_not_alone)
11234 << FirstDeclaratorInGroup->getSourceRange()
11235 << DD->getSourceRange();
11236 DiagnosedMultipleDecomps = true;
11239 // A declarator that uses 'auto' in any way other than to declare a
11240 // variable with a deduced type cannot be combined with any other
11241 // declarator in the same group.
11242 if (FirstNonDeducedAutoInGroup && !DiagnosedNonDeducedAuto) {
11243 Diag(FirstNonDeducedAutoInGroup->getLocation(),
11244 diag::err_auto_non_deduced_not_alone)
11245 << FirstNonDeducedAutoInGroup->getType()
11246 ->hasAutoForTrailingReturnType()
11247 << FirstDeclaratorInGroup->getSourceRange()
11248 << DD->getSourceRange();
11249 DiagnosedNonDeducedAuto = true;
11254 Decls.push_back(D);
11258 if (DeclSpec::isDeclRep(DS.getTypeSpecType())) {
11259 if (TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) {
11260 handleTagNumbering(Tag, S);
11261 if (FirstDeclaratorInGroup && !Tag->hasNameForLinkage() &&
11262 getLangOpts().CPlusPlus)
11263 Context.addDeclaratorForUnnamedTagDecl(Tag, FirstDeclaratorInGroup);
11267 return BuildDeclaratorGroup(Decls);
11270 /// BuildDeclaratorGroup - convert a list of declarations into a declaration
11271 /// group, performing any necessary semantic checking.
11272 Sema::DeclGroupPtrTy
11273 Sema::BuildDeclaratorGroup(MutableArrayRef<Decl *> Group) {
11274 // C++14 [dcl.spec.auto]p7: (DR1347)
11275 // If the type that replaces the placeholder type is not the same in each
11276 // deduction, the program is ill-formed.
11277 if (Group.size() > 1) {
11279 VarDecl *DeducedDecl = nullptr;
11280 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
11281 VarDecl *D = dyn_cast<VarDecl>(Group[i]);
11282 if (!D || D->isInvalidDecl())
11284 DeducedType *DT = D->getType()->getContainedDeducedType();
11285 if (!DT || DT->getDeducedType().isNull())
11287 if (Deduced.isNull()) {
11288 Deduced = DT->getDeducedType();
11290 } else if (!Context.hasSameType(DT->getDeducedType(), Deduced)) {
11291 auto *AT = dyn_cast<AutoType>(DT);
11292 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(),
11293 diag::err_auto_different_deductions)
11294 << (AT ? (unsigned)AT->getKeyword() : 3)
11295 << Deduced << DeducedDecl->getDeclName()
11296 << DT->getDeducedType() << D->getDeclName()
11297 << DeducedDecl->getInit()->getSourceRange()
11298 << D->getInit()->getSourceRange();
11299 D->setInvalidDecl();
11305 ActOnDocumentableDecls(Group);
11307 return DeclGroupPtrTy::make(
11308 DeclGroupRef::Create(Context, Group.data(), Group.size()));
11311 void Sema::ActOnDocumentableDecl(Decl *D) {
11312 ActOnDocumentableDecls(D);
11315 void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) {
11316 // Don't parse the comment if Doxygen diagnostics are ignored.
11317 if (Group.empty() || !Group[0])
11320 if (Diags.isIgnored(diag::warn_doc_param_not_found,
11321 Group[0]->getLocation()) &&
11322 Diags.isIgnored(diag::warn_unknown_comment_command_name,
11323 Group[0]->getLocation()))
11326 if (Group.size() >= 2) {
11327 // This is a decl group. Normally it will contain only declarations
11328 // produced from declarator list. But in case we have any definitions or
11329 // additional declaration references:
11330 // 'typedef struct S {} S;'
11331 // 'typedef struct S *S;'
11333 // FinalizeDeclaratorGroup adds these as separate declarations.
11334 Decl *MaybeTagDecl = Group[0];
11335 if (MaybeTagDecl && isa<TagDecl>(MaybeTagDecl)) {
11336 Group = Group.slice(1);
11340 // See if there are any new comments that are not attached to a decl.
11341 ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments();
11342 if (!Comments.empty() &&
11343 !Comments.back()->isAttached()) {
11344 // There is at least one comment that not attached to a decl.
11345 // Maybe it should be attached to one of these decls?
11347 // Note that this way we pick up not only comments that precede the
11348 // declaration, but also comments that *follow* the declaration -- thanks to
11349 // the lookahead in the lexer: we've consumed the semicolon and looked
11350 // ahead through comments.
11351 for (unsigned i = 0, e = Group.size(); i != e; ++i)
11352 Context.getCommentForDecl(Group[i], &PP);
11356 /// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator()
11357 /// to introduce parameters into function prototype scope.
11358 Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) {
11359 const DeclSpec &DS = D.getDeclSpec();
11361 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'.
11363 // C++03 [dcl.stc]p2 also permits 'auto'.
11364 StorageClass SC = SC_None;
11365 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
11367 } else if (getLangOpts().CPlusPlus &&
11368 DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
11370 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) {
11371 Diag(DS.getStorageClassSpecLoc(),
11372 diag::err_invalid_storage_class_in_func_decl);
11373 D.getMutableDeclSpec().ClearStorageClassSpecs();
11376 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
11377 Diag(DS.getThreadStorageClassSpecLoc(), diag::err_invalid_thread)
11378 << DeclSpec::getSpecifierName(TSCS);
11379 if (DS.isInlineSpecified())
11380 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
11381 << getLangOpts().CPlusPlus1z;
11382 if (DS.isConstexprSpecified())
11383 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr)
11385 if (DS.isConceptSpecified())
11386 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
11388 DiagnoseFunctionSpecifiers(DS);
11390 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
11391 QualType parmDeclType = TInfo->getType();
11393 if (getLangOpts().CPlusPlus) {
11394 // Check that there are no default arguments inside the type of this
11396 CheckExtraCXXDefaultArguments(D);
11398 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
11399 if (D.getCXXScopeSpec().isSet()) {
11400 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator)
11401 << D.getCXXScopeSpec().getRange();
11402 D.getCXXScopeSpec().clear();
11406 // Ensure we have a valid name
11407 IdentifierInfo *II = nullptr;
11409 II = D.getIdentifier();
11411 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name)
11412 << GetNameForDeclarator(D).getName();
11413 D.setInvalidType(true);
11417 // Check for redeclaration of parameters, e.g. int foo(int x, int x);
11419 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName,
11422 if (R.isSingleResult()) {
11423 NamedDecl *PrevDecl = R.getFoundDecl();
11424 if (PrevDecl->isTemplateParameter()) {
11425 // Maybe we will complain about the shadowed template parameter.
11426 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
11427 // Just pretend that we didn't see the previous declaration.
11428 PrevDecl = nullptr;
11429 } else if (S->isDeclScope(PrevDecl)) {
11430 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II;
11431 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
11433 // Recover by removing the name
11435 D.SetIdentifier(nullptr, D.getIdentifierLoc());
11436 D.setInvalidType(true);
11441 // Temporarily put parameter variables in the translation unit, not
11442 // the enclosing context. This prevents them from accidentally
11443 // looking like class members in C++.
11444 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(),
11446 D.getIdentifierLoc(), II,
11447 parmDeclType, TInfo,
11450 if (D.isInvalidType())
11451 New->setInvalidDecl();
11453 assert(S->isFunctionPrototypeScope());
11454 assert(S->getFunctionPrototypeDepth() >= 1);
11455 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1,
11456 S->getNextFunctionPrototypeIndex());
11458 // Add the parameter declaration into this scope.
11461 IdResolver.AddDecl(New);
11463 ProcessDeclAttributes(S, New, D);
11465 if (D.getDeclSpec().isModulePrivateSpecified())
11466 Diag(New->getLocation(), diag::err_module_private_local)
11467 << 1 << New->getDeclName()
11468 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
11469 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
11471 if (New->hasAttr<BlocksAttr>()) {
11472 Diag(New->getLocation(), diag::err_block_on_nonlocal);
11477 /// \brief Synthesizes a variable for a parameter arising from a
11479 ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC,
11480 SourceLocation Loc,
11482 /* FIXME: setting StartLoc == Loc.
11483 Would it be worth to modify callers so as to provide proper source
11484 location for the unnamed parameters, embedding the parameter's type? */
11485 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, nullptr,
11486 T, Context.getTrivialTypeSourceInfo(T, Loc),
11488 Param->setImplicit();
11492 void Sema::DiagnoseUnusedParameters(ArrayRef<ParmVarDecl *> Parameters) {
11493 // Don't diagnose unused-parameter errors in template instantiations; we
11494 // will already have done so in the template itself.
11495 if (inTemplateInstantiation())
11498 for (const ParmVarDecl *Parameter : Parameters) {
11499 if (!Parameter->isReferenced() && Parameter->getDeclName() &&
11500 !Parameter->hasAttr<UnusedAttr>()) {
11501 Diag(Parameter->getLocation(), diag::warn_unused_parameter)
11502 << Parameter->getDeclName();
11507 void Sema::DiagnoseSizeOfParametersAndReturnValue(
11508 ArrayRef<ParmVarDecl *> Parameters, QualType ReturnTy, NamedDecl *D) {
11509 if (LangOpts.NumLargeByValueCopy == 0) // No check.
11512 // Warn if the return value is pass-by-value and larger than the specified
11514 if (!ReturnTy->isDependentType() && ReturnTy.isPODType(Context)) {
11515 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity();
11516 if (Size > LangOpts.NumLargeByValueCopy)
11517 Diag(D->getLocation(), diag::warn_return_value_size)
11518 << D->getDeclName() << Size;
11521 // Warn if any parameter is pass-by-value and larger than the specified
11523 for (const ParmVarDecl *Parameter : Parameters) {
11524 QualType T = Parameter->getType();
11525 if (T->isDependentType() || !T.isPODType(Context))
11527 unsigned Size = Context.getTypeSizeInChars(T).getQuantity();
11528 if (Size > LangOpts.NumLargeByValueCopy)
11529 Diag(Parameter->getLocation(), diag::warn_parameter_size)
11530 << Parameter->getDeclName() << Size;
11534 ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc,
11535 SourceLocation NameLoc, IdentifierInfo *Name,
11536 QualType T, TypeSourceInfo *TSInfo,
11538 // In ARC, infer a lifetime qualifier for appropriate parameter types.
11539 if (getLangOpts().ObjCAutoRefCount &&
11540 T.getObjCLifetime() == Qualifiers::OCL_None &&
11541 T->isObjCLifetimeType()) {
11543 Qualifiers::ObjCLifetime lifetime;
11545 // Special cases for arrays:
11546 // - if it's const, use __unsafe_unretained
11547 // - otherwise, it's an error
11548 if (T->isArrayType()) {
11549 if (!T.isConstQualified()) {
11550 DelayedDiagnostics.add(
11551 sema::DelayedDiagnostic::makeForbiddenType(
11552 NameLoc, diag::err_arc_array_param_no_ownership, T, false));
11554 lifetime = Qualifiers::OCL_ExplicitNone;
11556 lifetime = T->getObjCARCImplicitLifetime();
11558 T = Context.getLifetimeQualifiedType(T, lifetime);
11561 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name,
11562 Context.getAdjustedParameterType(T),
11563 TSInfo, SC, nullptr);
11565 // Parameters can not be abstract class types.
11566 // For record types, this is done by the AbstractClassUsageDiagnoser once
11567 // the class has been completely parsed.
11568 if (!CurContext->isRecord() &&
11569 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl,
11570 AbstractParamType))
11571 New->setInvalidDecl();
11573 // Parameter declarators cannot be interface types. All ObjC objects are
11574 // passed by reference.
11575 if (T->isObjCObjectType()) {
11576 SourceLocation TypeEndLoc =
11577 getLocForEndOfToken(TSInfo->getTypeLoc().getLocEnd());
11579 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T
11580 << FixItHint::CreateInsertion(TypeEndLoc, "*");
11581 T = Context.getObjCObjectPointerType(T);
11585 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
11586 // duration shall not be qualified by an address-space qualifier."
11587 // Since all parameters have automatic store duration, they can not have
11588 // an address space.
11589 if (T.getAddressSpace() != 0) {
11590 // OpenCL allows function arguments declared to be an array of a type
11591 // to be qualified with an address space.
11592 if (!(getLangOpts().OpenCL && T->isArrayType())) {
11593 Diag(NameLoc, diag::err_arg_with_address_space);
11594 New->setInvalidDecl();
11601 void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
11602 SourceLocation LocAfterDecls) {
11603 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
11605 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared'
11606 // for a K&R function.
11607 if (!FTI.hasPrototype) {
11608 for (int i = FTI.NumParams; i != 0; /* decrement in loop */) {
11610 if (FTI.Params[i].Param == nullptr) {
11611 SmallString<256> Code;
11612 llvm::raw_svector_ostream(Code)
11613 << " int " << FTI.Params[i].Ident->getName() << ";\n";
11614 Diag(FTI.Params[i].IdentLoc, diag::ext_param_not_declared)
11615 << FTI.Params[i].Ident
11616 << FixItHint::CreateInsertion(LocAfterDecls, Code);
11618 // Implicitly declare the argument as type 'int' for lack of a better
11620 AttributeFactory attrs;
11621 DeclSpec DS(attrs);
11622 const char* PrevSpec; // unused
11623 unsigned DiagID; // unused
11624 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.Params[i].IdentLoc, PrevSpec,
11625 DiagID, Context.getPrintingPolicy());
11626 // Use the identifier location for the type source range.
11627 DS.SetRangeStart(FTI.Params[i].IdentLoc);
11628 DS.SetRangeEnd(FTI.Params[i].IdentLoc);
11629 Declarator ParamD(DS, Declarator::KNRTypeListContext);
11630 ParamD.SetIdentifier(FTI.Params[i].Ident, FTI.Params[i].IdentLoc);
11631 FTI.Params[i].Param = ActOnParamDeclarator(S, ParamD);
11638 Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D,
11639 MultiTemplateParamsArg TemplateParameterLists,
11640 SkipBodyInfo *SkipBody) {
11641 assert(getCurFunctionDecl() == nullptr && "Function parsing confused");
11642 assert(D.isFunctionDeclarator() && "Not a function declarator!");
11643 Scope *ParentScope = FnBodyScope->getParent();
11645 D.setFunctionDefinitionKind(FDK_Definition);
11646 Decl *DP = HandleDeclarator(ParentScope, D, TemplateParameterLists);
11647 return ActOnStartOfFunctionDef(FnBodyScope, DP, SkipBody);
11650 void Sema::ActOnFinishInlineFunctionDef(FunctionDecl *D) {
11651 Consumer.HandleInlineFunctionDefinition(D);
11654 static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD,
11655 const FunctionDecl*& PossibleZeroParamPrototype) {
11656 // Don't warn about invalid declarations.
11657 if (FD->isInvalidDecl())
11660 // Or declarations that aren't global.
11661 if (!FD->isGlobal())
11664 // Don't warn about C++ member functions.
11665 if (isa<CXXMethodDecl>(FD))
11668 // Don't warn about 'main'.
11672 // Don't warn about inline functions.
11673 if (FD->isInlined())
11676 // Don't warn about function templates.
11677 if (FD->getDescribedFunctionTemplate())
11680 // Don't warn about function template specializations.
11681 if (FD->isFunctionTemplateSpecialization())
11684 // Don't warn for OpenCL kernels.
11685 if (FD->hasAttr<OpenCLKernelAttr>())
11688 // Don't warn on explicitly deleted functions.
11689 if (FD->isDeleted())
11692 bool MissingPrototype = true;
11693 for (const FunctionDecl *Prev = FD->getPreviousDecl();
11694 Prev; Prev = Prev->getPreviousDecl()) {
11695 // Ignore any declarations that occur in function or method
11696 // scope, because they aren't visible from the header.
11697 if (Prev->getLexicalDeclContext()->isFunctionOrMethod())
11700 MissingPrototype = !Prev->getType()->isFunctionProtoType();
11701 if (FD->getNumParams() == 0)
11702 PossibleZeroParamPrototype = Prev;
11706 return MissingPrototype;
11710 Sema::CheckForFunctionRedefinition(FunctionDecl *FD,
11711 const FunctionDecl *EffectiveDefinition,
11712 SkipBodyInfo *SkipBody) {
11713 const FunctionDecl *Definition = EffectiveDefinition;
11715 if (!FD->isDefined(Definition))
11718 if (canRedefineFunction(Definition, getLangOpts()))
11721 // If we don't have a visible definition of the function, and it's inline or
11722 // a template, skip the new definition.
11723 if (SkipBody && !hasVisibleDefinition(Definition) &&
11724 (Definition->getFormalLinkage() == InternalLinkage ||
11725 Definition->isInlined() ||
11726 Definition->getDescribedFunctionTemplate() ||
11727 Definition->getNumTemplateParameterLists())) {
11728 SkipBody->ShouldSkip = true;
11729 if (auto *TD = Definition->getDescribedFunctionTemplate())
11730 makeMergedDefinitionVisible(TD, FD->getLocation());
11731 makeMergedDefinitionVisible(const_cast<FunctionDecl*>(Definition),
11732 FD->getLocation());
11736 if (getLangOpts().GNUMode && Definition->isInlineSpecified() &&
11737 Definition->getStorageClass() == SC_Extern)
11738 Diag(FD->getLocation(), diag::err_redefinition_extern_inline)
11739 << FD->getDeclName() << getLangOpts().CPlusPlus;
11741 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName();
11743 Diag(Definition->getLocation(), diag::note_previous_definition);
11744 FD->setInvalidDecl();
11747 static void RebuildLambdaScopeInfo(CXXMethodDecl *CallOperator,
11749 CXXRecordDecl *const LambdaClass = CallOperator->getParent();
11751 LambdaScopeInfo *LSI = S.PushLambdaScope();
11752 LSI->CallOperator = CallOperator;
11753 LSI->Lambda = LambdaClass;
11754 LSI->ReturnType = CallOperator->getReturnType();
11755 const LambdaCaptureDefault LCD = LambdaClass->getLambdaCaptureDefault();
11757 if (LCD == LCD_None)
11758 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_None;
11759 else if (LCD == LCD_ByCopy)
11760 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByval;
11761 else if (LCD == LCD_ByRef)
11762 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByref;
11763 DeclarationNameInfo DNI = CallOperator->getNameInfo();
11765 LSI->IntroducerRange = DNI.getCXXOperatorNameRange();
11766 LSI->Mutable = !CallOperator->isConst();
11768 // Add the captures to the LSI so they can be noted as already
11769 // captured within tryCaptureVar.
11770 auto I = LambdaClass->field_begin();
11771 for (const auto &C : LambdaClass->captures()) {
11772 if (C.capturesVariable()) {
11773 VarDecl *VD = C.getCapturedVar();
11774 if (VD->isInitCapture())
11775 S.CurrentInstantiationScope->InstantiatedLocal(VD, VD);
11776 QualType CaptureType = VD->getType();
11777 const bool ByRef = C.getCaptureKind() == LCK_ByRef;
11778 LSI->addCapture(VD, /*IsBlock*/false, ByRef,
11779 /*RefersToEnclosingVariableOrCapture*/true, C.getLocation(),
11780 /*EllipsisLoc*/C.isPackExpansion()
11781 ? C.getEllipsisLoc() : SourceLocation(),
11782 CaptureType, /*Expr*/ nullptr);
11784 } else if (C.capturesThis()) {
11785 LSI->addThisCapture(/*Nested*/ false, C.getLocation(),
11787 C.getCaptureKind() == LCK_StarThis);
11789 LSI->addVLATypeCapture(C.getLocation(), I->getType());
11795 Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D,
11796 SkipBodyInfo *SkipBody) {
11799 FunctionDecl *FD = nullptr;
11801 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D))
11802 FD = FunTmpl->getTemplatedDecl();
11804 FD = cast<FunctionDecl>(D);
11806 // Check for defining attributes before the check for redefinition.
11807 if (const auto *Attr = FD->getAttr<AliasAttr>()) {
11808 Diag(Attr->getLocation(), diag::err_alias_is_definition) << FD << 0;
11809 FD->dropAttr<AliasAttr>();
11810 FD->setInvalidDecl();
11812 if (const auto *Attr = FD->getAttr<IFuncAttr>()) {
11813 Diag(Attr->getLocation(), diag::err_alias_is_definition) << FD << 1;
11814 FD->dropAttr<IFuncAttr>();
11815 FD->setInvalidDecl();
11818 // See if this is a redefinition.
11819 if (!FD->isLateTemplateParsed()) {
11820 CheckForFunctionRedefinition(FD, nullptr, SkipBody);
11822 // If we're skipping the body, we're done. Don't enter the scope.
11823 if (SkipBody && SkipBody->ShouldSkip)
11827 // Mark this function as "will have a body eventually". This lets users to
11828 // call e.g. isInlineDefinitionExternallyVisible while we're still parsing
11830 FD->setWillHaveBody();
11832 // If we are instantiating a generic lambda call operator, push
11833 // a LambdaScopeInfo onto the function stack. But use the information
11834 // that's already been calculated (ActOnLambdaExpr) to prime the current
11835 // LambdaScopeInfo.
11836 // When the template operator is being specialized, the LambdaScopeInfo,
11837 // has to be properly restored so that tryCaptureVariable doesn't try
11838 // and capture any new variables. In addition when calculating potential
11839 // captures during transformation of nested lambdas, it is necessary to
11840 // have the LSI properly restored.
11841 if (isGenericLambdaCallOperatorSpecialization(FD)) {
11842 assert(inTemplateInstantiation() &&
11843 "There should be an active template instantiation on the stack "
11844 "when instantiating a generic lambda!");
11845 RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this);
11847 // Enter a new function scope
11848 PushFunctionScope();
11851 // Builtin functions cannot be defined.
11852 if (unsigned BuiltinID = FD->getBuiltinID()) {
11853 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) &&
11854 !Context.BuiltinInfo.isPredefinedRuntimeFunction(BuiltinID)) {
11855 Diag(FD->getLocation(), diag::err_builtin_definition) << FD;
11856 FD->setInvalidDecl();
11860 // The return type of a function definition must be complete
11861 // (C99 6.9.1p3, C++ [dcl.fct]p6).
11862 QualType ResultType = FD->getReturnType();
11863 if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
11864 !FD->isInvalidDecl() &&
11865 RequireCompleteType(FD->getLocation(), ResultType,
11866 diag::err_func_def_incomplete_result))
11867 FD->setInvalidDecl();
11870 PushDeclContext(FnBodyScope, FD);
11872 // Check the validity of our function parameters
11873 CheckParmsForFunctionDef(FD->parameters(),
11874 /*CheckParameterNames=*/true);
11876 // Add non-parameter declarations already in the function to the current
11879 for (Decl *NPD : FD->decls()) {
11880 auto *NonParmDecl = dyn_cast<NamedDecl>(NPD);
11883 assert(!isa<ParmVarDecl>(NonParmDecl) &&
11884 "parameters should not be in newly created FD yet");
11886 // If the decl has a name, make it accessible in the current scope.
11887 if (NonParmDecl->getDeclName())
11888 PushOnScopeChains(NonParmDecl, FnBodyScope, /*AddToContext=*/false);
11890 // Similarly, dive into enums and fish their constants out, making them
11891 // accessible in this scope.
11892 if (auto *ED = dyn_cast<EnumDecl>(NonParmDecl)) {
11893 for (auto *EI : ED->enumerators())
11894 PushOnScopeChains(EI, FnBodyScope, /*AddToContext=*/false);
11899 // Introduce our parameters into the function scope
11900 for (auto Param : FD->parameters()) {
11901 Param->setOwningFunction(FD);
11903 // If this has an identifier, add it to the scope stack.
11904 if (Param->getIdentifier() && FnBodyScope) {
11905 CheckShadow(FnBodyScope, Param);
11907 PushOnScopeChains(Param, FnBodyScope);
11911 // Ensure that the function's exception specification is instantiated.
11912 if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>())
11913 ResolveExceptionSpec(D->getLocation(), FPT);
11915 // dllimport cannot be applied to non-inline function definitions.
11916 if (FD->hasAttr<DLLImportAttr>() && !FD->isInlined() &&
11917 !FD->isTemplateInstantiation()) {
11918 assert(!FD->hasAttr<DLLExportAttr>());
11919 Diag(FD->getLocation(), diag::err_attribute_dllimport_function_definition);
11920 FD->setInvalidDecl();
11923 // We want to attach documentation to original Decl (which might be
11924 // a function template).
11925 ActOnDocumentableDecl(D);
11926 if (getCurLexicalContext()->isObjCContainer() &&
11927 getCurLexicalContext()->getDeclKind() != Decl::ObjCCategoryImpl &&
11928 getCurLexicalContext()->getDeclKind() != Decl::ObjCImplementation)
11929 Diag(FD->getLocation(), diag::warn_function_def_in_objc_container);
11934 /// \brief Given the set of return statements within a function body,
11935 /// compute the variables that are subject to the named return value
11938 /// Each of the variables that is subject to the named return value
11939 /// optimization will be marked as NRVO variables in the AST, and any
11940 /// return statement that has a marked NRVO variable as its NRVO candidate can
11941 /// use the named return value optimization.
11943 /// This function applies a very simplistic algorithm for NRVO: if every return
11944 /// statement in the scope of a variable has the same NRVO candidate, that
11945 /// candidate is an NRVO variable.
11946 void Sema::computeNRVO(Stmt *Body, FunctionScopeInfo *Scope) {
11947 ReturnStmt **Returns = Scope->Returns.data();
11949 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) {
11950 if (const VarDecl *NRVOCandidate = Returns[I]->getNRVOCandidate()) {
11951 if (!NRVOCandidate->isNRVOVariable())
11952 Returns[I]->setNRVOCandidate(nullptr);
11957 bool Sema::canDelayFunctionBody(const Declarator &D) {
11958 // We can't delay parsing the body of a constexpr function template (yet).
11959 if (D.getDeclSpec().isConstexprSpecified())
11962 // We can't delay parsing the body of a function template with a deduced
11963 // return type (yet).
11964 if (D.getDeclSpec().hasAutoTypeSpec()) {
11965 // If the placeholder introduces a non-deduced trailing return type,
11966 // we can still delay parsing it.
11967 if (D.getNumTypeObjects()) {
11968 const auto &Outer = D.getTypeObject(D.getNumTypeObjects() - 1);
11969 if (Outer.Kind == DeclaratorChunk::Function &&
11970 Outer.Fun.hasTrailingReturnType()) {
11971 QualType Ty = GetTypeFromParser(Outer.Fun.getTrailingReturnType());
11972 return Ty.isNull() || !Ty->isUndeducedType();
11981 bool Sema::canSkipFunctionBody(Decl *D) {
11982 // We cannot skip the body of a function (or function template) which is
11983 // constexpr, since we may need to evaluate its body in order to parse the
11984 // rest of the file.
11985 // We cannot skip the body of a function with an undeduced return type,
11986 // because any callers of that function need to know the type.
11987 if (const FunctionDecl *FD = D->getAsFunction())
11988 if (FD->isConstexpr() || FD->getReturnType()->isUndeducedType())
11990 return Consumer.shouldSkipFunctionBody(D);
11993 Decl *Sema::ActOnSkippedFunctionBody(Decl *Decl) {
11994 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Decl))
11995 FD->setHasSkippedBody();
11996 else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(Decl))
11997 MD->setHasSkippedBody();
12001 Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) {
12002 return ActOnFinishFunctionBody(D, BodyArg, false);
12005 Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
12006 bool IsInstantiation) {
12007 FunctionDecl *FD = dcl ? dcl->getAsFunction() : nullptr;
12009 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
12010 sema::AnalysisBasedWarnings::Policy *ActivePolicy = nullptr;
12012 if (getLangOpts().CoroutinesTS && getCurFunction()->CoroutinePromise)
12013 CheckCompletedCoroutineBody(FD, Body);
12018 if (getLangOpts().CPlusPlus14) {
12019 if (!FD->isInvalidDecl() && Body && !FD->isDependentContext() &&
12020 FD->getReturnType()->isUndeducedType()) {
12021 // If the function has a deduced result type but contains no 'return'
12022 // statements, the result type as written must be exactly 'auto', and
12023 // the deduced result type is 'void'.
12024 if (!FD->getReturnType()->getAs<AutoType>()) {
12025 Diag(dcl->getLocation(), diag::err_auto_fn_no_return_but_not_auto)
12026 << FD->getReturnType();
12027 FD->setInvalidDecl();
12029 // Substitute 'void' for the 'auto' in the type.
12030 TypeLoc ResultType = getReturnTypeLoc(FD);
12031 Context.adjustDeducedFunctionResultType(
12032 FD, SubstAutoType(ResultType.getType(), Context.VoidTy));
12035 } else if (getLangOpts().CPlusPlus11 && isLambdaCallOperator(FD)) {
12036 // In C++11, we don't use 'auto' deduction rules for lambda call
12037 // operators because we don't support return type deduction.
12038 auto *LSI = getCurLambda();
12039 if (LSI->HasImplicitReturnType) {
12040 deduceClosureReturnType(*LSI);
12042 // C++11 [expr.prim.lambda]p4:
12043 // [...] if there are no return statements in the compound-statement
12044 // [the deduced type is] the type void
12046 LSI->ReturnType.isNull() ? Context.VoidTy : LSI->ReturnType;
12048 // Update the return type to the deduced type.
12049 const FunctionProtoType *Proto =
12050 FD->getType()->getAs<FunctionProtoType>();
12051 FD->setType(Context.getFunctionType(RetType, Proto->getParamTypes(),
12052 Proto->getExtProtoInfo()));
12056 // The only way to be included in UndefinedButUsed is if there is an
12057 // ODR use before the definition. Avoid the expensive map lookup if this
12058 // is the first declaration.
12059 if (!FD->isFirstDecl() && FD->getPreviousDecl()->isUsed()) {
12060 if (!FD->isExternallyVisible())
12061 UndefinedButUsed.erase(FD);
12062 else if (FD->isInlined() &&
12063 !LangOpts.GNUInline &&
12064 (!FD->getPreviousDecl()->hasAttr<GNUInlineAttr>()))
12065 UndefinedButUsed.erase(FD);
12068 // If the function implicitly returns zero (like 'main') or is naked,
12069 // don't complain about missing return statements.
12070 if (FD->hasImplicitReturnZero() || FD->hasAttr<NakedAttr>())
12071 WP.disableCheckFallThrough();
12073 // MSVC permits the use of pure specifier (=0) on function definition,
12074 // defined at class scope, warn about this non-standard construct.
12075 if (getLangOpts().MicrosoftExt && FD->isPure() && FD->isCanonicalDecl())
12076 Diag(FD->getLocation(), diag::ext_pure_function_definition);
12078 if (!FD->isInvalidDecl()) {
12079 // Don't diagnose unused parameters of defaulted or deleted functions.
12080 if (!FD->isDeleted() && !FD->isDefaulted())
12081 DiagnoseUnusedParameters(FD->parameters());
12082 DiagnoseSizeOfParametersAndReturnValue(FD->parameters(),
12083 FD->getReturnType(), FD);
12085 // If this is a structor, we need a vtable.
12086 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD))
12087 MarkVTableUsed(FD->getLocation(), Constructor->getParent());
12088 else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(FD))
12089 MarkVTableUsed(FD->getLocation(), Destructor->getParent());
12091 // Try to apply the named return value optimization. We have to check
12092 // if we can do this here because lambdas keep return statements around
12093 // to deduce an implicit return type.
12094 if (getLangOpts().CPlusPlus && FD->getReturnType()->isRecordType() &&
12095 !FD->isDependentContext())
12096 computeNRVO(Body, getCurFunction());
12099 // GNU warning -Wmissing-prototypes:
12100 // Warn if a global function is defined without a previous
12101 // prototype declaration. This warning is issued even if the
12102 // definition itself provides a prototype. The aim is to detect
12103 // global functions that fail to be declared in header files.
12104 const FunctionDecl *PossibleZeroParamPrototype = nullptr;
12105 if (ShouldWarnAboutMissingPrototype(FD, PossibleZeroParamPrototype)) {
12106 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD;
12108 if (PossibleZeroParamPrototype) {
12109 // We found a declaration that is not a prototype,
12110 // but that could be a zero-parameter prototype
12111 if (TypeSourceInfo *TI =
12112 PossibleZeroParamPrototype->getTypeSourceInfo()) {
12113 TypeLoc TL = TI->getTypeLoc();
12114 if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>())
12115 Diag(PossibleZeroParamPrototype->getLocation(),
12116 diag::note_declaration_not_a_prototype)
12117 << PossibleZeroParamPrototype
12118 << FixItHint::CreateInsertion(FTL.getRParenLoc(), "void");
12122 // GNU warning -Wstrict-prototypes
12123 // Warn if K&R function is defined without a previous declaration.
12124 // This warning is issued only if the definition itself does not provide
12125 // a prototype. Only K&R definitions do not provide a prototype.
12126 // An empty list in a function declarator that is part of a definition
12127 // of that function specifies that the function has no parameters
12128 // (C99 6.7.5.3p14)
12129 if (!FD->hasWrittenPrototype() && FD->getNumParams() > 0 &&
12130 !LangOpts.CPlusPlus) {
12131 TypeSourceInfo *TI = FD->getTypeSourceInfo();
12132 TypeLoc TL = TI->getTypeLoc();
12133 FunctionTypeLoc FTL = TL.getAsAdjusted<FunctionTypeLoc>();
12134 Diag(FTL.getLParenLoc(), diag::warn_strict_prototypes) << 1;
12138 if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) {
12139 const CXXMethodDecl *KeyFunction;
12140 if (MD->isOutOfLine() && (MD = MD->getCanonicalDecl()) &&
12142 (KeyFunction = Context.getCurrentKeyFunction(MD->getParent())) &&
12143 MD == KeyFunction->getCanonicalDecl()) {
12144 // Update the key-function state if necessary for this ABI.
12145 if (FD->isInlined() &&
12146 !Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
12147 Context.setNonKeyFunction(MD);
12149 // If the newly-chosen key function is already defined, then we
12150 // need to mark the vtable as used retroactively.
12151 KeyFunction = Context.getCurrentKeyFunction(MD->getParent());
12152 const FunctionDecl *Definition;
12153 if (KeyFunction && KeyFunction->isDefined(Definition))
12154 MarkVTableUsed(Definition->getLocation(), MD->getParent(), true);
12156 // We just defined they key function; mark the vtable as used.
12157 MarkVTableUsed(FD->getLocation(), MD->getParent(), true);
12162 assert((FD == getCurFunctionDecl() || getCurLambda()->CallOperator == FD) &&
12163 "Function parsing confused");
12164 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) {
12165 assert(MD == getCurMethodDecl() && "Method parsing confused");
12167 if (!MD->isInvalidDecl()) {
12168 DiagnoseUnusedParameters(MD->parameters());
12169 DiagnoseSizeOfParametersAndReturnValue(MD->parameters(),
12170 MD->getReturnType(), MD);
12173 computeNRVO(Body, getCurFunction());
12175 if (getCurFunction()->ObjCShouldCallSuper) {
12176 Diag(MD->getLocEnd(), diag::warn_objc_missing_super_call)
12177 << MD->getSelector().getAsString();
12178 getCurFunction()->ObjCShouldCallSuper = false;
12180 if (getCurFunction()->ObjCWarnForNoDesignatedInitChain) {
12181 const ObjCMethodDecl *InitMethod = nullptr;
12182 bool isDesignated =
12183 MD->isDesignatedInitializerForTheInterface(&InitMethod);
12184 assert(isDesignated && InitMethod);
12185 (void)isDesignated;
12187 auto superIsNSObject = [&](const ObjCMethodDecl *MD) {
12188 auto IFace = MD->getClassInterface();
12191 auto SuperD = IFace->getSuperClass();
12194 return SuperD->getIdentifier() ==
12195 NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject);
12197 // Don't issue this warning for unavailable inits or direct subclasses
12199 if (!MD->isUnavailable() && !superIsNSObject(MD)) {
12200 Diag(MD->getLocation(),
12201 diag::warn_objc_designated_init_missing_super_call);
12202 Diag(InitMethod->getLocation(),
12203 diag::note_objc_designated_init_marked_here);
12205 getCurFunction()->ObjCWarnForNoDesignatedInitChain = false;
12207 if (getCurFunction()->ObjCWarnForNoInitDelegation) {
12208 // Don't issue this warning for unavaialable inits.
12209 if (!MD->isUnavailable())
12210 Diag(MD->getLocation(),
12211 diag::warn_objc_secondary_init_missing_init_call);
12212 getCurFunction()->ObjCWarnForNoInitDelegation = false;
12218 if (Body && getCurFunction()->HasPotentialAvailabilityViolations)
12219 DiagnoseUnguardedAvailabilityViolations(dcl);
12221 assert(!getCurFunction()->ObjCShouldCallSuper &&
12222 "This should only be set for ObjC methods, which should have been "
12223 "handled in the block above.");
12225 // Verify and clean out per-function state.
12226 if (Body && (!FD || !FD->isDefaulted())) {
12227 // C++ constructors that have function-try-blocks can't have return
12228 // statements in the handlers of that block. (C++ [except.handle]p14)
12230 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body))
12231 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body));
12233 // Verify that gotos and switch cases don't jump into scopes illegally.
12234 if (getCurFunction()->NeedsScopeChecking() &&
12235 !PP.isCodeCompletionEnabled())
12236 DiagnoseInvalidJumps(Body);
12238 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) {
12239 if (!Destructor->getParent()->isDependentType())
12240 CheckDestructor(Destructor);
12242 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
12243 Destructor->getParent());
12246 // If any errors have occurred, clear out any temporaries that may have
12247 // been leftover. This ensures that these temporaries won't be picked up for
12248 // deletion in some later function.
12249 if (getDiagnostics().hasErrorOccurred() ||
12250 getDiagnostics().getSuppressAllDiagnostics()) {
12251 DiscardCleanupsInEvaluationContext();
12253 if (!getDiagnostics().hasUncompilableErrorOccurred() &&
12254 !isa<FunctionTemplateDecl>(dcl)) {
12255 // Since the body is valid, issue any analysis-based warnings that are
12257 ActivePolicy = &WP;
12260 if (!IsInstantiation && FD && FD->isConstexpr() && !FD->isInvalidDecl() &&
12261 (!CheckConstexprFunctionDecl(FD) ||
12262 !CheckConstexprFunctionBody(FD, Body)))
12263 FD->setInvalidDecl();
12265 if (FD && FD->hasAttr<NakedAttr>()) {
12266 for (const Stmt *S : Body->children()) {
12267 // Allow local register variables without initializer as they don't
12268 // require prologue.
12269 bool RegisterVariables = false;
12270 if (auto *DS = dyn_cast<DeclStmt>(S)) {
12271 for (const auto *Decl : DS->decls()) {
12272 if (const auto *Var = dyn_cast<VarDecl>(Decl)) {
12273 RegisterVariables =
12274 Var->hasAttr<AsmLabelAttr>() && !Var->hasInit();
12275 if (!RegisterVariables)
12280 if (RegisterVariables)
12282 if (!isa<AsmStmt>(S) && !isa<NullStmt>(S)) {
12283 Diag(S->getLocStart(), diag::err_non_asm_stmt_in_naked_function);
12284 Diag(FD->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
12285 FD->setInvalidDecl();
12291 assert(ExprCleanupObjects.size() ==
12292 ExprEvalContexts.back().NumCleanupObjects &&
12293 "Leftover temporaries in function");
12294 assert(!Cleanup.exprNeedsCleanups() && "Unaccounted cleanups in function");
12295 assert(MaybeODRUseExprs.empty() &&
12296 "Leftover expressions for odr-use checking");
12299 if (!IsInstantiation)
12302 PopFunctionScopeInfo(ActivePolicy, dcl);
12303 // If any errors have occurred, clear out any temporaries that may have
12304 // been leftover. This ensures that these temporaries won't be picked up for
12305 // deletion in some later function.
12306 if (getDiagnostics().hasErrorOccurred()) {
12307 DiscardCleanupsInEvaluationContext();
12313 /// When we finish delayed parsing of an attribute, we must attach it to the
12315 void Sema::ActOnFinishDelayedAttribute(Scope *S, Decl *D,
12316 ParsedAttributes &Attrs) {
12317 // Always attach attributes to the underlying decl.
12318 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
12319 D = TD->getTemplatedDecl();
12320 ProcessDeclAttributeList(S, D, Attrs.getList());
12322 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(D))
12323 if (Method->isStatic())
12324 checkThisInStaticMemberFunctionAttributes(Method);
12327 /// ImplicitlyDefineFunction - An undeclared identifier was used in a function
12328 /// call, forming a call to an implicitly defined function (per C99 6.5.1p2).
12329 NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
12330 IdentifierInfo &II, Scope *S) {
12331 // Before we produce a declaration for an implicitly defined
12332 // function, see whether there was a locally-scoped declaration of
12333 // this name as a function or variable. If so, use that
12334 // (non-visible) declaration, and complain about it.
12335 if (NamedDecl *ExternCPrev = findLocallyScopedExternCDecl(&II)) {
12336 Diag(Loc, diag::warn_use_out_of_scope_declaration) << ExternCPrev;
12337 Diag(ExternCPrev->getLocation(), diag::note_previous_declaration);
12338 return ExternCPrev;
12341 // Extension in C99. Legal in C90, but warn about it.
12343 if (II.getName().startswith("__builtin_"))
12344 diag_id = diag::warn_builtin_unknown;
12345 else if (getLangOpts().C99)
12346 diag_id = diag::ext_implicit_function_decl;
12348 diag_id = diag::warn_implicit_function_decl;
12349 Diag(Loc, diag_id) << &II;
12351 // Because typo correction is expensive, only do it if the implicit
12352 // function declaration is going to be treated as an error.
12353 if (Diags.getDiagnosticLevel(diag_id, Loc) >= DiagnosticsEngine::Error) {
12354 TypoCorrection Corrected;
12356 (Corrected = CorrectTypo(
12357 DeclarationNameInfo(&II, Loc), LookupOrdinaryName, S, nullptr,
12358 llvm::make_unique<DeclFilterCCC<FunctionDecl>>(), CTK_NonError)))
12359 diagnoseTypo(Corrected, PDiag(diag::note_function_suggestion),
12360 /*ErrorRecovery*/false);
12363 // Set a Declarator for the implicit definition: int foo();
12365 AttributeFactory attrFactory;
12366 DeclSpec DS(attrFactory);
12368 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID,
12369 Context.getPrintingPolicy());
12370 (void)Error; // Silence warning.
12371 assert(!Error && "Error setting up implicit decl!");
12372 SourceLocation NoLoc;
12373 Declarator D(DS, Declarator::BlockContext);
12374 D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false,
12375 /*IsAmbiguous=*/false,
12376 /*LParenLoc=*/NoLoc,
12377 /*Params=*/nullptr,
12379 /*EllipsisLoc=*/NoLoc,
12380 /*RParenLoc=*/NoLoc,
12382 /*RefQualifierIsLvalueRef=*/true,
12383 /*RefQualifierLoc=*/NoLoc,
12384 /*ConstQualifierLoc=*/NoLoc,
12385 /*VolatileQualifierLoc=*/NoLoc,
12386 /*RestrictQualifierLoc=*/NoLoc,
12387 /*MutableLoc=*/NoLoc,
12389 /*ESpecRange=*/SourceRange(),
12390 /*Exceptions=*/nullptr,
12391 /*ExceptionRanges=*/nullptr,
12392 /*NumExceptions=*/0,
12393 /*NoexceptExpr=*/nullptr,
12394 /*ExceptionSpecTokens=*/nullptr,
12395 /*DeclsInPrototype=*/None,
12397 DS.getAttributes(),
12399 D.SetIdentifier(&II, Loc);
12401 // Insert this function into translation-unit scope.
12403 DeclContext *PrevDC = CurContext;
12404 CurContext = Context.getTranslationUnitDecl();
12406 FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(TUScope, D));
12409 CurContext = PrevDC;
12411 AddKnownFunctionAttributes(FD);
12416 /// \brief Adds any function attributes that we know a priori based on
12417 /// the declaration of this function.
12419 /// These attributes can apply both to implicitly-declared builtins
12420 /// (like __builtin___printf_chk) or to library-declared functions
12421 /// like NSLog or printf.
12423 /// We need to check for duplicate attributes both here and where user-written
12424 /// attributes are applied to declarations.
12425 void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) {
12426 if (FD->isInvalidDecl())
12429 // If this is a built-in function, map its builtin attributes to
12430 // actual attributes.
12431 if (unsigned BuiltinID = FD->getBuiltinID()) {
12432 // Handle printf-formatting attributes.
12433 unsigned FormatIdx;
12435 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) {
12436 if (!FD->hasAttr<FormatAttr>()) {
12437 const char *fmt = "printf";
12438 unsigned int NumParams = FD->getNumParams();
12439 if (FormatIdx < NumParams && // NumParams may be 0 (e.g. vfprintf)
12440 FD->getParamDecl(FormatIdx)->getType()->isObjCObjectPointerType())
12442 FD->addAttr(FormatAttr::CreateImplicit(Context,
12443 &Context.Idents.get(fmt),
12445 HasVAListArg ? 0 : FormatIdx+2,
12446 FD->getLocation()));
12449 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx,
12451 if (!FD->hasAttr<FormatAttr>())
12452 FD->addAttr(FormatAttr::CreateImplicit(Context,
12453 &Context.Idents.get("scanf"),
12455 HasVAListArg ? 0 : FormatIdx+2,
12456 FD->getLocation()));
12459 // Mark const if we don't care about errno and that is the only
12460 // thing preventing the function from being const. This allows
12461 // IRgen to use LLVM intrinsics for such functions.
12462 if (!getLangOpts().MathErrno &&
12463 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) {
12464 if (!FD->hasAttr<ConstAttr>())
12465 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
12468 if (Context.BuiltinInfo.isReturnsTwice(BuiltinID) &&
12469 !FD->hasAttr<ReturnsTwiceAttr>())
12470 FD->addAttr(ReturnsTwiceAttr::CreateImplicit(Context,
12471 FD->getLocation()));
12472 if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->hasAttr<NoThrowAttr>())
12473 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
12474 if (Context.BuiltinInfo.isPure(BuiltinID) && !FD->hasAttr<PureAttr>())
12475 FD->addAttr(PureAttr::CreateImplicit(Context, FD->getLocation()));
12476 if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->hasAttr<ConstAttr>())
12477 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
12478 if (getLangOpts().CUDA && Context.BuiltinInfo.isTSBuiltin(BuiltinID) &&
12479 !FD->hasAttr<CUDADeviceAttr>() && !FD->hasAttr<CUDAHostAttr>()) {
12480 // Add the appropriate attribute, depending on the CUDA compilation mode
12481 // and which target the builtin belongs to. For example, during host
12482 // compilation, aux builtins are __device__, while the rest are __host__.
12483 if (getLangOpts().CUDAIsDevice !=
12484 Context.BuiltinInfo.isAuxBuiltinID(BuiltinID))
12485 FD->addAttr(CUDADeviceAttr::CreateImplicit(Context, FD->getLocation()));
12487 FD->addAttr(CUDAHostAttr::CreateImplicit(Context, FD->getLocation()));
12491 // If C++ exceptions are enabled but we are told extern "C" functions cannot
12492 // throw, add an implicit nothrow attribute to any extern "C" function we come
12494 if (getLangOpts().CXXExceptions && getLangOpts().ExternCNoUnwind &&
12495 FD->isExternC() && !FD->hasAttr<NoThrowAttr>()) {
12496 const auto *FPT = FD->getType()->getAs<FunctionProtoType>();
12497 if (!FPT || FPT->getExceptionSpecType() == EST_None)
12498 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
12501 IdentifierInfo *Name = FD->getIdentifier();
12504 if ((!getLangOpts().CPlusPlus &&
12505 FD->getDeclContext()->isTranslationUnit()) ||
12506 (isa<LinkageSpecDecl>(FD->getDeclContext()) &&
12507 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() ==
12508 LinkageSpecDecl::lang_c)) {
12509 // Okay: this could be a libc/libm/Objective-C function we know
12514 if (Name->isStr("asprintf") || Name->isStr("vasprintf")) {
12515 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be
12516 // target-specific builtins, perhaps?
12517 if (!FD->hasAttr<FormatAttr>())
12518 FD->addAttr(FormatAttr::CreateImplicit(Context,
12519 &Context.Idents.get("printf"), 2,
12520 Name->isStr("vasprintf") ? 0 : 3,
12521 FD->getLocation()));
12524 if (Name->isStr("__CFStringMakeConstantString")) {
12525 // We already have a __builtin___CFStringMakeConstantString,
12526 // but builds that use -fno-constant-cfstrings don't go through that.
12527 if (!FD->hasAttr<FormatArgAttr>())
12528 FD->addAttr(FormatArgAttr::CreateImplicit(Context, 1,
12529 FD->getLocation()));
12533 TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
12534 TypeSourceInfo *TInfo) {
12535 assert(D.getIdentifier() && "Wrong callback for declspec without declarator");
12536 assert(!T.isNull() && "GetTypeForDeclarator() returned null type");
12539 assert(D.isInvalidType() && "no declarator info for valid type");
12540 TInfo = Context.getTrivialTypeSourceInfo(T);
12543 // Scope manipulation handled by caller.
12544 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext,
12546 D.getIdentifierLoc(),
12550 // Bail out immediately if we have an invalid declaration.
12551 if (D.isInvalidType()) {
12552 NewTD->setInvalidDecl();
12556 if (D.getDeclSpec().isModulePrivateSpecified()) {
12557 if (CurContext->isFunctionOrMethod())
12558 Diag(NewTD->getLocation(), diag::err_module_private_local)
12559 << 2 << NewTD->getDeclName()
12560 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
12561 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
12563 NewTD->setModulePrivate();
12566 // C++ [dcl.typedef]p8:
12567 // If the typedef declaration defines an unnamed class (or
12568 // enum), the first typedef-name declared by the declaration
12569 // to be that class type (or enum type) is used to denote the
12570 // class type (or enum type) for linkage purposes only.
12571 // We need to check whether the type was declared in the declaration.
12572 switch (D.getDeclSpec().getTypeSpecType()) {
12575 case TST_interface:
12578 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
12579 setTagNameForLinkagePurposes(tagFromDeclSpec, NewTD);
12590 /// \brief Check that this is a valid underlying type for an enum declaration.
12591 bool Sema::CheckEnumUnderlyingType(TypeSourceInfo *TI) {
12592 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
12593 QualType T = TI->getType();
12595 if (T->isDependentType())
12598 if (const BuiltinType *BT = T->getAs<BuiltinType>())
12599 if (BT->isInteger())
12602 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) << T;
12606 /// Check whether this is a valid redeclaration of a previous enumeration.
12607 /// \return true if the redeclaration was invalid.
12608 bool Sema::CheckEnumRedeclaration(
12609 SourceLocation EnumLoc, bool IsScoped, QualType EnumUnderlyingTy,
12610 bool EnumUnderlyingIsImplicit, const EnumDecl *Prev) {
12611 bool IsFixed = !EnumUnderlyingTy.isNull();
12613 if (IsScoped != Prev->isScoped()) {
12614 Diag(EnumLoc, diag::err_enum_redeclare_scoped_mismatch)
12615 << Prev->isScoped();
12616 Diag(Prev->getLocation(), diag::note_previous_declaration);
12620 if (IsFixed && Prev->isFixed()) {
12621 if (!EnumUnderlyingTy->isDependentType() &&
12622 !Prev->getIntegerType()->isDependentType() &&
12623 !Context.hasSameUnqualifiedType(EnumUnderlyingTy,
12624 Prev->getIntegerType())) {
12625 // TODO: Highlight the underlying type of the redeclaration.
12626 Diag(EnumLoc, diag::err_enum_redeclare_type_mismatch)
12627 << EnumUnderlyingTy << Prev->getIntegerType();
12628 Diag(Prev->getLocation(), diag::note_previous_declaration)
12629 << Prev->getIntegerTypeRange();
12632 } else if (IsFixed && !Prev->isFixed() && EnumUnderlyingIsImplicit) {
12634 } else if (!IsFixed && Prev->isFixed() && !Prev->getIntegerTypeSourceInfo()) {
12636 } else if (IsFixed != Prev->isFixed()) {
12637 Diag(EnumLoc, diag::err_enum_redeclare_fixed_mismatch)
12638 << Prev->isFixed();
12639 Diag(Prev->getLocation(), diag::note_previous_declaration);
12646 /// \brief Get diagnostic %select index for tag kind for
12647 /// redeclaration diagnostic message.
12648 /// WARNING: Indexes apply to particular diagnostics only!
12650 /// \returns diagnostic %select index.
12651 static unsigned getRedeclDiagFromTagKind(TagTypeKind Tag) {
12653 case TTK_Struct: return 0;
12654 case TTK_Interface: return 1;
12655 case TTK_Class: return 2;
12656 default: llvm_unreachable("Invalid tag kind for redecl diagnostic!");
12660 /// \brief Determine if tag kind is a class-key compatible with
12661 /// class for redeclaration (class, struct, or __interface).
12663 /// \returns true iff the tag kind is compatible.
12664 static bool isClassCompatTagKind(TagTypeKind Tag)
12666 return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface;
12669 Sema::NonTagKind Sema::getNonTagTypeDeclKind(const Decl *PrevDecl,
12671 if (isa<TypedefDecl>(PrevDecl))
12672 return NTK_Typedef;
12673 else if (isa<TypeAliasDecl>(PrevDecl))
12674 return NTK_TypeAlias;
12675 else if (isa<ClassTemplateDecl>(PrevDecl))
12676 return NTK_Template;
12677 else if (isa<TypeAliasTemplateDecl>(PrevDecl))
12678 return NTK_TypeAliasTemplate;
12679 else if (isa<TemplateTemplateParmDecl>(PrevDecl))
12680 return NTK_TemplateTemplateArgument;
12683 case TTK_Interface:
12685 return getLangOpts().CPlusPlus ? NTK_NonClass : NTK_NonStruct;
12687 return NTK_NonUnion;
12689 return NTK_NonEnum;
12691 llvm_unreachable("invalid TTK");
12694 /// \brief Determine whether a tag with a given kind is acceptable
12695 /// as a redeclaration of the given tag declaration.
12697 /// \returns true if the new tag kind is acceptable, false otherwise.
12698 bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous,
12699 TagTypeKind NewTag, bool isDefinition,
12700 SourceLocation NewTagLoc,
12701 const IdentifierInfo *Name) {
12702 // C++ [dcl.type.elab]p3:
12703 // The class-key or enum keyword present in the
12704 // elaborated-type-specifier shall agree in kind with the
12705 // declaration to which the name in the elaborated-type-specifier
12706 // refers. This rule also applies to the form of
12707 // elaborated-type-specifier that declares a class-name or
12708 // friend class since it can be construed as referring to the
12709 // definition of the class. Thus, in any
12710 // elaborated-type-specifier, the enum keyword shall be used to
12711 // refer to an enumeration (7.2), the union class-key shall be
12712 // used to refer to a union (clause 9), and either the class or
12713 // struct class-key shall be used to refer to a class (clause 9)
12714 // declared using the class or struct class-key.
12715 TagTypeKind OldTag = Previous->getTagKind();
12716 if (!isDefinition || !isClassCompatTagKind(NewTag))
12717 if (OldTag == NewTag)
12720 if (isClassCompatTagKind(OldTag) && isClassCompatTagKind(NewTag)) {
12721 // Warn about the struct/class tag mismatch.
12722 bool isTemplate = false;
12723 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous))
12724 isTemplate = Record->getDescribedClassTemplate();
12726 if (inTemplateInstantiation()) {
12727 // In a template instantiation, do not offer fix-its for tag mismatches
12728 // since they usually mess up the template instead of fixing the problem.
12729 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
12730 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12731 << getRedeclDiagFromTagKind(OldTag);
12735 if (isDefinition) {
12736 // On definitions, check previous tags and issue a fix-it for each
12737 // one that doesn't match the current tag.
12738 if (Previous->getDefinition()) {
12739 // Don't suggest fix-its for redefinitions.
12743 bool previousMismatch = false;
12744 for (auto I : Previous->redecls()) {
12745 if (I->getTagKind() != NewTag) {
12746 if (!previousMismatch) {
12747 previousMismatch = true;
12748 Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch)
12749 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12750 << getRedeclDiagFromTagKind(I->getTagKind());
12752 Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion)
12753 << getRedeclDiagFromTagKind(NewTag)
12754 << FixItHint::CreateReplacement(I->getInnerLocStart(),
12755 TypeWithKeyword::getTagTypeKindName(NewTag));
12761 // Check for a previous definition. If current tag and definition
12762 // are same type, do nothing. If no definition, but disagree with
12763 // with previous tag type, give a warning, but no fix-it.
12764 const TagDecl *Redecl = Previous->getDefinition() ?
12765 Previous->getDefinition() : Previous;
12766 if (Redecl->getTagKind() == NewTag) {
12770 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
12771 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12772 << getRedeclDiagFromTagKind(OldTag);
12773 Diag(Redecl->getLocation(), diag::note_previous_use);
12775 // If there is a previous definition, suggest a fix-it.
12776 if (Previous->getDefinition()) {
12777 Diag(NewTagLoc, diag::note_struct_class_suggestion)
12778 << getRedeclDiagFromTagKind(Redecl->getTagKind())
12779 << FixItHint::CreateReplacement(SourceRange(NewTagLoc),
12780 TypeWithKeyword::getTagTypeKindName(Redecl->getTagKind()));
12788 /// Add a minimal nested name specifier fixit hint to allow lookup of a tag name
12789 /// from an outer enclosing namespace or file scope inside a friend declaration.
12790 /// This should provide the commented out code in the following snippet:
12794 /// struct Y { friend struct /*N::*/ X; };
12797 static FixItHint createFriendTagNNSFixIt(Sema &SemaRef, NamedDecl *ND, Scope *S,
12798 SourceLocation NameLoc) {
12799 // While the decl is in a namespace, do repeated lookup of that name and see
12800 // if we get the same namespace back. If we do not, continue until
12801 // translation unit scope, at which point we have a fully qualified NNS.
12802 SmallVector<IdentifierInfo *, 4> Namespaces;
12803 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
12804 for (; !DC->isTranslationUnit(); DC = DC->getParent()) {
12805 // This tag should be declared in a namespace, which can only be enclosed by
12806 // other namespaces. Bail if there's an anonymous namespace in the chain.
12807 NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(DC);
12808 if (!Namespace || Namespace->isAnonymousNamespace())
12809 return FixItHint();
12810 IdentifierInfo *II = Namespace->getIdentifier();
12811 Namespaces.push_back(II);
12812 NamedDecl *Lookup = SemaRef.LookupSingleName(
12813 S, II, NameLoc, Sema::LookupNestedNameSpecifierName);
12814 if (Lookup == Namespace)
12818 // Once we have all the namespaces, reverse them to go outermost first, and
12820 SmallString<64> Insertion;
12821 llvm::raw_svector_ostream OS(Insertion);
12822 if (DC->isTranslationUnit())
12824 std::reverse(Namespaces.begin(), Namespaces.end());
12825 for (auto *II : Namespaces)
12826 OS << II->getName() << "::";
12827 return FixItHint::CreateInsertion(NameLoc, Insertion);
12830 /// \brief Determine whether a tag originally declared in context \p OldDC can
12831 /// be redeclared with an unqualfied name in \p NewDC (assuming name lookup
12832 /// found a declaration in \p OldDC as a previous decl, perhaps through a
12833 /// using-declaration).
12834 static bool isAcceptableTagRedeclContext(Sema &S, DeclContext *OldDC,
12835 DeclContext *NewDC) {
12836 OldDC = OldDC->getRedeclContext();
12837 NewDC = NewDC->getRedeclContext();
12839 if (OldDC->Equals(NewDC))
12842 // In MSVC mode, we allow a redeclaration if the contexts are related (either
12843 // encloses the other).
12844 if (S.getLangOpts().MSVCCompat &&
12845 (OldDC->Encloses(NewDC) || NewDC->Encloses(OldDC)))
12851 /// \brief This is invoked when we see 'struct foo' or 'struct {'. In the
12852 /// former case, Name will be non-null. In the later case, Name will be null.
12853 /// TagSpec indicates what kind of tag this is. TUK indicates whether this is a
12854 /// reference/declaration/definition of a tag.
12856 /// \param IsTypeSpecifier \c true if this is a type-specifier (or
12857 /// trailing-type-specifier) other than one in an alias-declaration.
12859 /// \param SkipBody If non-null, will be set to indicate if the caller should
12860 /// skip the definition of this tag and treat it as if it were a declaration.
12861 Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
12862 SourceLocation KWLoc, CXXScopeSpec &SS,
12863 IdentifierInfo *Name, SourceLocation NameLoc,
12864 AttributeList *Attr, AccessSpecifier AS,
12865 SourceLocation ModulePrivateLoc,
12866 MultiTemplateParamsArg TemplateParameterLists,
12867 bool &OwnedDecl, bool &IsDependent,
12868 SourceLocation ScopedEnumKWLoc,
12869 bool ScopedEnumUsesClassTag,
12870 TypeResult UnderlyingType,
12871 bool IsTypeSpecifier, SkipBodyInfo *SkipBody) {
12872 // If this is not a definition, it must have a name.
12873 IdentifierInfo *OrigName = Name;
12874 assert((Name != nullptr || TUK == TUK_Definition) &&
12875 "Nameless record must be a definition!");
12876 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference);
12879 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
12880 bool ScopedEnum = ScopedEnumKWLoc.isValid();
12882 // FIXME: Check member specializations more carefully.
12883 bool isMemberSpecialization = false;
12884 bool Invalid = false;
12886 // We only need to do this matching if we have template parameters
12887 // or a scope specifier, which also conveniently avoids this work
12888 // for non-C++ cases.
12889 if (TemplateParameterLists.size() > 0 ||
12890 (SS.isNotEmpty() && TUK != TUK_Reference)) {
12891 if (TemplateParameterList *TemplateParams =
12892 MatchTemplateParametersToScopeSpecifier(
12893 KWLoc, NameLoc, SS, nullptr, TemplateParameterLists,
12894 TUK == TUK_Friend, isMemberSpecialization, Invalid)) {
12895 if (Kind == TTK_Enum) {
12896 Diag(KWLoc, diag::err_enum_template);
12900 if (TemplateParams->size() > 0) {
12901 // This is a declaration or definition of a class template (which may
12902 // be a member of another template).
12908 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc,
12909 SS, Name, NameLoc, Attr,
12910 TemplateParams, AS,
12912 /*FriendLoc*/SourceLocation(),
12913 TemplateParameterLists.size()-1,
12914 TemplateParameterLists.data(),
12916 return Result.get();
12918 // The "template<>" header is extraneous.
12919 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
12920 << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
12921 isMemberSpecialization = true;
12926 // Figure out the underlying type if this a enum declaration. We need to do
12927 // this early, because it's needed to detect if this is an incompatible
12929 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying;
12930 bool EnumUnderlyingIsImplicit = false;
12932 if (Kind == TTK_Enum) {
12933 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum))
12934 // No underlying type explicitly specified, or we failed to parse the
12935 // type, default to int.
12936 EnumUnderlying = Context.IntTy.getTypePtr();
12937 else if (UnderlyingType.get()) {
12938 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
12939 // integral type; any cv-qualification is ignored.
12940 TypeSourceInfo *TI = nullptr;
12941 GetTypeFromParser(UnderlyingType.get(), &TI);
12942 EnumUnderlying = TI;
12944 if (CheckEnumUnderlyingType(TI))
12945 // Recover by falling back to int.
12946 EnumUnderlying = Context.IntTy.getTypePtr();
12948 if (DiagnoseUnexpandedParameterPack(TI->getTypeLoc().getBeginLoc(), TI,
12949 UPPC_FixedUnderlyingType))
12950 EnumUnderlying = Context.IntTy.getTypePtr();
12952 } else if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
12953 if (getLangOpts().MSVCCompat || TUK == TUK_Definition) {
12954 // Microsoft enums are always of int type.
12955 EnumUnderlying = Context.IntTy.getTypePtr();
12956 EnumUnderlyingIsImplicit = true;
12961 DeclContext *SearchDC = CurContext;
12962 DeclContext *DC = CurContext;
12963 bool isStdBadAlloc = false;
12964 bool isStdAlignValT = false;
12966 RedeclarationKind Redecl = ForRedeclaration;
12967 if (TUK == TUK_Friend || TUK == TUK_Reference)
12968 Redecl = NotForRedeclaration;
12970 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl);
12971 if (Name && SS.isNotEmpty()) {
12972 // We have a nested-name tag ('struct foo::bar').
12974 // Check for invalid 'foo::'.
12975 if (SS.isInvalid()) {
12977 goto CreateNewDecl;
12980 // If this is a friend or a reference to a class in a dependent
12981 // context, don't try to make a decl for it.
12982 if (TUK == TUK_Friend || TUK == TUK_Reference) {
12983 DC = computeDeclContext(SS, false);
12985 IsDependent = true;
12989 DC = computeDeclContext(SS, true);
12991 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec)
12997 if (RequireCompleteDeclContext(SS, DC))
13001 // Look-up name inside 'foo::'.
13002 LookupQualifiedName(Previous, DC);
13004 if (Previous.isAmbiguous())
13007 if (Previous.empty()) {
13008 // Name lookup did not find anything. However, if the
13009 // nested-name-specifier refers to the current instantiation,
13010 // and that current instantiation has any dependent base
13011 // classes, we might find something at instantiation time: treat
13012 // this as a dependent elaborated-type-specifier.
13013 // But this only makes any sense for reference-like lookups.
13014 if (Previous.wasNotFoundInCurrentInstantiation() &&
13015 (TUK == TUK_Reference || TUK == TUK_Friend)) {
13016 IsDependent = true;
13020 // A tag 'foo::bar' must already exist.
13021 Diag(NameLoc, diag::err_not_tag_in_scope)
13022 << Kind << Name << DC << SS.getRange();
13025 goto CreateNewDecl;
13028 // C++14 [class.mem]p14:
13029 // If T is the name of a class, then each of the following shall have a
13030 // name different from T:
13031 // -- every member of class T that is itself a type
13032 if (TUK != TUK_Reference && TUK != TUK_Friend &&
13033 DiagnoseClassNameShadow(SearchDC, DeclarationNameInfo(Name, NameLoc)))
13036 // If this is a named struct, check to see if there was a previous forward
13037 // declaration or definition.
13038 // FIXME: We're looking into outer scopes here, even when we
13039 // shouldn't be. Doing so can result in ambiguities that we
13040 // shouldn't be diagnosing.
13041 LookupName(Previous, S);
13043 // When declaring or defining a tag, ignore ambiguities introduced
13044 // by types using'ed into this scope.
13045 if (Previous.isAmbiguous() &&
13046 (TUK == TUK_Definition || TUK == TUK_Declaration)) {
13047 LookupResult::Filter F = Previous.makeFilter();
13048 while (F.hasNext()) {
13049 NamedDecl *ND = F.next();
13050 if (!ND->getDeclContext()->getRedeclContext()->Equals(
13051 SearchDC->getRedeclContext()))
13057 // C++11 [namespace.memdef]p3:
13058 // If the name in a friend declaration is neither qualified nor
13059 // a template-id and the declaration is a function or an
13060 // elaborated-type-specifier, the lookup to determine whether
13061 // the entity has been previously declared shall not consider
13062 // any scopes outside the innermost enclosing namespace.
13064 // MSVC doesn't implement the above rule for types, so a friend tag
13065 // declaration may be a redeclaration of a type declared in an enclosing
13066 // scope. They do implement this rule for friend functions.
13068 // Does it matter that this should be by scope instead of by
13069 // semantic context?
13070 if (!Previous.empty() && TUK == TUK_Friend) {
13071 DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext();
13072 LookupResult::Filter F = Previous.makeFilter();
13073 bool FriendSawTagOutsideEnclosingNamespace = false;
13074 while (F.hasNext()) {
13075 NamedDecl *ND = F.next();
13076 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
13077 if (DC->isFileContext() &&
13078 !EnclosingNS->Encloses(ND->getDeclContext())) {
13079 if (getLangOpts().MSVCCompat)
13080 FriendSawTagOutsideEnclosingNamespace = true;
13087 // Diagnose this MSVC extension in the easy case where lookup would have
13088 // unambiguously found something outside the enclosing namespace.
13089 if (Previous.isSingleResult() && FriendSawTagOutsideEnclosingNamespace) {
13090 NamedDecl *ND = Previous.getFoundDecl();
13091 Diag(NameLoc, diag::ext_friend_tag_redecl_outside_namespace)
13092 << createFriendTagNNSFixIt(*this, ND, S, NameLoc);
13096 // Note: there used to be some attempt at recovery here.
13097 if (Previous.isAmbiguous())
13100 if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) {
13101 // FIXME: This makes sure that we ignore the contexts associated
13102 // with C structs, unions, and enums when looking for a matching
13103 // tag declaration or definition. See the similar lookup tweak
13104 // in Sema::LookupName; is there a better way to deal with this?
13105 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
13106 SearchDC = SearchDC->getParent();
13110 if (Previous.isSingleResult() &&
13111 Previous.getFoundDecl()->isTemplateParameter()) {
13112 // Maybe we will complain about the shadowed template parameter.
13113 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
13114 // Just pretend that we didn't see the previous declaration.
13118 if (getLangOpts().CPlusPlus && Name && DC && StdNamespace &&
13119 DC->Equals(getStdNamespace())) {
13120 if (Name->isStr("bad_alloc")) {
13121 // This is a declaration of or a reference to "std::bad_alloc".
13122 isStdBadAlloc = true;
13124 // If std::bad_alloc has been implicitly declared (but made invisible to
13125 // name lookup), fill in this implicit declaration as the previous
13126 // declaration, so that the declarations get chained appropriately.
13127 if (Previous.empty() && StdBadAlloc)
13128 Previous.addDecl(getStdBadAlloc());
13129 } else if (Name->isStr("align_val_t")) {
13130 isStdAlignValT = true;
13131 if (Previous.empty() && StdAlignValT)
13132 Previous.addDecl(getStdAlignValT());
13136 // If we didn't find a previous declaration, and this is a reference
13137 // (or friend reference), move to the correct scope. In C++, we
13138 // also need to do a redeclaration lookup there, just in case
13139 // there's a shadow friend decl.
13140 if (Name && Previous.empty() &&
13141 (TUK == TUK_Reference || TUK == TUK_Friend)) {
13142 if (Invalid) goto CreateNewDecl;
13143 assert(SS.isEmpty());
13145 if (TUK == TUK_Reference) {
13146 // C++ [basic.scope.pdecl]p5:
13147 // -- for an elaborated-type-specifier of the form
13149 // class-key identifier
13151 // if the elaborated-type-specifier is used in the
13152 // decl-specifier-seq or parameter-declaration-clause of a
13153 // function defined in namespace scope, the identifier is
13154 // declared as a class-name in the namespace that contains
13155 // the declaration; otherwise, except as a friend
13156 // declaration, the identifier is declared in the smallest
13157 // non-class, non-function-prototype scope that contains the
13160 // C99 6.7.2.3p8 has a similar (but not identical!) provision for
13161 // C structs and unions.
13163 // It is an error in C++ to declare (rather than define) an enum
13164 // type, including via an elaborated type specifier. We'll
13165 // diagnose that later; for now, declare the enum in the same
13166 // scope as we would have picked for any other tag type.
13168 // GNU C also supports this behavior as part of its incomplete
13169 // enum types extension, while GNU C++ does not.
13171 // Find the context where we'll be declaring the tag.
13172 // FIXME: We would like to maintain the current DeclContext as the
13173 // lexical context,
13174 SearchDC = getTagInjectionContext(SearchDC);
13176 // Find the scope where we'll be declaring the tag.
13177 S = getTagInjectionScope(S, getLangOpts());
13179 assert(TUK == TUK_Friend);
13180 // C++ [namespace.memdef]p3:
13181 // If a friend declaration in a non-local class first declares a
13182 // class or function, the friend class or function is a member of
13183 // the innermost enclosing namespace.
13184 SearchDC = SearchDC->getEnclosingNamespaceContext();
13187 // In C++, we need to do a redeclaration lookup to properly
13188 // diagnose some problems.
13189 // FIXME: redeclaration lookup is also used (with and without C++) to find a
13190 // hidden declaration so that we don't get ambiguity errors when using a
13191 // type declared by an elaborated-type-specifier. In C that is not correct
13192 // and we should instead merge compatible types found by lookup.
13193 if (getLangOpts().CPlusPlus) {
13194 Previous.setRedeclarationKind(ForRedeclaration);
13195 LookupQualifiedName(Previous, SearchDC);
13197 Previous.setRedeclarationKind(ForRedeclaration);
13198 LookupName(Previous, S);
13202 // If we have a known previous declaration to use, then use it.
13203 if (Previous.empty() && SkipBody && SkipBody->Previous)
13204 Previous.addDecl(SkipBody->Previous);
13206 if (!Previous.empty()) {
13207 NamedDecl *PrevDecl = Previous.getFoundDecl();
13208 NamedDecl *DirectPrevDecl = Previous.getRepresentativeDecl();
13210 // It's okay to have a tag decl in the same scope as a typedef
13211 // which hides a tag decl in the same scope. Finding this
13212 // insanity with a redeclaration lookup can only actually happen
13215 // This is also okay for elaborated-type-specifiers, which is
13216 // technically forbidden by the current standard but which is
13217 // okay according to the likely resolution of an open issue;
13218 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
13219 if (getLangOpts().CPlusPlus) {
13220 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
13221 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
13222 TagDecl *Tag = TT->getDecl();
13223 if (Tag->getDeclName() == Name &&
13224 Tag->getDeclContext()->getRedeclContext()
13225 ->Equals(TD->getDeclContext()->getRedeclContext())) {
13228 Previous.addDecl(Tag);
13229 Previous.resolveKind();
13235 // If this is a redeclaration of a using shadow declaration, it must
13236 // declare a tag in the same context. In MSVC mode, we allow a
13237 // redefinition if either context is within the other.
13238 if (auto *Shadow = dyn_cast<UsingShadowDecl>(DirectPrevDecl)) {
13239 auto *OldTag = dyn_cast<TagDecl>(PrevDecl);
13240 if (SS.isEmpty() && TUK != TUK_Reference && TUK != TUK_Friend &&
13241 isDeclInScope(Shadow, SearchDC, S, isMemberSpecialization) &&
13242 !(OldTag && isAcceptableTagRedeclContext(
13243 *this, OldTag->getDeclContext(), SearchDC))) {
13244 Diag(KWLoc, diag::err_using_decl_conflict_reverse);
13245 Diag(Shadow->getTargetDecl()->getLocation(),
13246 diag::note_using_decl_target);
13247 Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl)
13249 // Recover by ignoring the old declaration.
13251 goto CreateNewDecl;
13255 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
13256 // If this is a use of a previous tag, or if the tag is already declared
13257 // in the same scope (so that the definition/declaration completes or
13258 // rementions the tag), reuse the decl.
13259 if (TUK == TUK_Reference || TUK == TUK_Friend ||
13260 isDeclInScope(DirectPrevDecl, SearchDC, S,
13261 SS.isNotEmpty() || isMemberSpecialization)) {
13262 // Make sure that this wasn't declared as an enum and now used as a
13263 // struct or something similar.
13264 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind,
13265 TUK == TUK_Definition, KWLoc,
13267 bool SafeToContinue
13268 = (PrevTagDecl->getTagKind() != TTK_Enum &&
13270 if (SafeToContinue)
13271 Diag(KWLoc, diag::err_use_with_wrong_tag)
13273 << FixItHint::CreateReplacement(SourceRange(KWLoc),
13274 PrevTagDecl->getKindName());
13276 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
13277 Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
13279 if (SafeToContinue)
13280 Kind = PrevTagDecl->getTagKind();
13282 // Recover by making this an anonymous redefinition.
13289 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
13290 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);
13292 // If this is an elaborated-type-specifier for a scoped enumeration,
13293 // the 'class' keyword is not necessary and not permitted.
13294 if (TUK == TUK_Reference || TUK == TUK_Friend) {
13296 Diag(ScopedEnumKWLoc, diag::err_enum_class_reference)
13297 << PrevEnum->isScoped()
13298 << FixItHint::CreateRemoval(ScopedEnumKWLoc);
13299 return PrevTagDecl;
13302 QualType EnumUnderlyingTy;
13303 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
13304 EnumUnderlyingTy = TI->getType().getUnqualifiedType();
13305 else if (const Type *T = EnumUnderlying.dyn_cast<const Type*>())
13306 EnumUnderlyingTy = QualType(T, 0);
13308 // All conflicts with previous declarations are recovered by
13309 // returning the previous declaration, unless this is a definition,
13310 // in which case we want the caller to bail out.
13311 if (CheckEnumRedeclaration(NameLoc.isValid() ? NameLoc : KWLoc,
13312 ScopedEnum, EnumUnderlyingTy,
13313 EnumUnderlyingIsImplicit, PrevEnum))
13314 return TUK == TUK_Declaration ? PrevTagDecl : nullptr;
13317 // C++11 [class.mem]p1:
13318 // A member shall not be declared twice in the member-specification,
13319 // except that a nested class or member class template can be declared
13320 // and then later defined.
13321 if (TUK == TUK_Declaration && PrevDecl->isCXXClassMember() &&
13322 S->isDeclScope(PrevDecl)) {
13323 Diag(NameLoc, diag::ext_member_redeclared);
13324 Diag(PrevTagDecl->getLocation(), diag::note_previous_declaration);
13328 // If this is a use, just return the declaration we found, unless
13329 // we have attributes.
13330 if (TUK == TUK_Reference || TUK == TUK_Friend) {
13332 // FIXME: Diagnose these attributes. For now, we create a new
13333 // declaration to hold them.
13334 } else if (TUK == TUK_Reference &&
13335 (PrevTagDecl->getFriendObjectKind() ==
13336 Decl::FOK_Undeclared ||
13337 PP.getModuleContainingLocation(
13338 PrevDecl->getLocation()) !=
13339 PP.getModuleContainingLocation(KWLoc)) &&
13341 // This declaration is a reference to an existing entity, but
13342 // has different visibility from that entity: it either makes
13343 // a friend visible or it makes a type visible in a new module.
13344 // In either case, create a new declaration. We only do this if
13345 // the declaration would have meant the same thing if no prior
13346 // declaration were found, that is, if it was found in the same
13347 // scope where we would have injected a declaration.
13348 if (!getTagInjectionContext(CurContext)->getRedeclContext()
13349 ->Equals(PrevDecl->getDeclContext()->getRedeclContext()))
13350 return PrevTagDecl;
13351 // This is in the injected scope, create a new declaration in
13353 S = getTagInjectionScope(S, getLangOpts());
13355 return PrevTagDecl;
13359 // Diagnose attempts to redefine a tag.
13360 if (TUK == TUK_Definition) {
13361 if (NamedDecl *Def = PrevTagDecl->getDefinition()) {
13362 // If we're defining a specialization and the previous definition
13363 // is from an implicit instantiation, don't emit an error
13364 // here; we'll catch this in the general case below.
13365 bool IsExplicitSpecializationAfterInstantiation = false;
13366 if (isMemberSpecialization) {
13367 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Def))
13368 IsExplicitSpecializationAfterInstantiation =
13369 RD->getTemplateSpecializationKind() !=
13370 TSK_ExplicitSpecialization;
13371 else if (EnumDecl *ED = dyn_cast<EnumDecl>(Def))
13372 IsExplicitSpecializationAfterInstantiation =
13373 ED->getTemplateSpecializationKind() !=
13374 TSK_ExplicitSpecialization;
13377 NamedDecl *Hidden = nullptr;
13378 if (SkipBody && getLangOpts().CPlusPlus &&
13379 !hasVisibleDefinition(Def, &Hidden)) {
13380 // There is a definition of this tag, but it is not visible. We
13381 // explicitly make use of C++'s one definition rule here, and
13382 // assume that this definition is identical to the hidden one
13383 // we already have. Make the existing definition visible and
13384 // use it in place of this one.
13385 SkipBody->ShouldSkip = true;
13386 makeMergedDefinitionVisible(Hidden, KWLoc);
13388 } else if (!IsExplicitSpecializationAfterInstantiation) {
13389 // A redeclaration in function prototype scope in C isn't
13390 // visible elsewhere, so merely issue a warning.
13391 if (!getLangOpts().CPlusPlus && S->containedInPrototypeScope())
13392 Diag(NameLoc, diag::warn_redefinition_in_param_list) << Name;
13394 Diag(NameLoc, diag::err_redefinition) << Name;
13395 Diag(Def->getLocation(), diag::note_previous_definition);
13396 // If this is a redefinition, recover by making this
13397 // struct be anonymous, which will make any later
13398 // references get the previous definition.
13404 // If the type is currently being defined, complain
13405 // about a nested redefinition.
13406 auto *TD = Context.getTagDeclType(PrevTagDecl)->getAsTagDecl();
13407 if (TD->isBeingDefined()) {
13408 Diag(NameLoc, diag::err_nested_redefinition) << Name;
13409 Diag(PrevTagDecl->getLocation(),
13410 diag::note_previous_definition);
13417 // Okay, this is definition of a previously declared or referenced
13418 // tag. We're going to create a new Decl for it.
13421 // Okay, we're going to make a redeclaration. If this is some kind
13422 // of reference, make sure we build the redeclaration in the same DC
13423 // as the original, and ignore the current access specifier.
13424 if (TUK == TUK_Friend || TUK == TUK_Reference) {
13425 SearchDC = PrevTagDecl->getDeclContext();
13429 // If we get here we have (another) forward declaration or we
13430 // have a definition. Just create a new decl.
13433 // If we get here, this is a definition of a new tag type in a nested
13434 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a
13435 // new decl/type. We set PrevDecl to NULL so that the entities
13436 // have distinct types.
13439 // If we get here, we're going to create a new Decl. If PrevDecl
13440 // is non-NULL, it's a definition of the tag declared by
13441 // PrevDecl. If it's NULL, we have a new definition.
13443 // Otherwise, PrevDecl is not a tag, but was found with tag
13444 // lookup. This is only actually possible in C++, where a few
13445 // things like templates still live in the tag namespace.
13447 // Use a better diagnostic if an elaborated-type-specifier
13448 // found the wrong kind of type on the first
13449 // (non-redeclaration) lookup.
13450 if ((TUK == TUK_Reference || TUK == TUK_Friend) &&
13451 !Previous.isForRedeclaration()) {
13452 NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl, Kind);
13453 Diag(NameLoc, diag::err_tag_reference_non_tag) << PrevDecl << NTK
13455 Diag(PrevDecl->getLocation(), diag::note_declared_at);
13458 // Otherwise, only diagnose if the declaration is in scope.
13459 } else if (!isDeclInScope(DirectPrevDecl, SearchDC, S,
13460 SS.isNotEmpty() || isMemberSpecialization)) {
13463 // Diagnose implicit declarations introduced by elaborated types.
13464 } else if (TUK == TUK_Reference || TUK == TUK_Friend) {
13465 NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl, Kind);
13466 Diag(NameLoc, diag::err_tag_reference_conflict) << NTK;
13467 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
13470 // Otherwise it's a declaration. Call out a particularly common
13472 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
13474 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
13475 Diag(NameLoc, diag::err_tag_definition_of_typedef)
13476 << Name << Kind << TND->getUnderlyingType();
13477 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
13480 // Otherwise, diagnose.
13482 // The tag name clashes with something else in the target scope,
13483 // issue an error and recover by making this tag be anonymous.
13484 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
13485 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
13490 // The existing declaration isn't relevant to us; we're in a
13491 // new scope, so clear out the previous declaration.
13498 TagDecl *PrevDecl = nullptr;
13499 if (Previous.isSingleResult())
13500 PrevDecl = cast<TagDecl>(Previous.getFoundDecl());
13502 // If there is an identifier, use the location of the identifier as the
13503 // location of the decl, otherwise use the location of the struct/union
13505 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc;
13507 // Otherwise, create a new declaration. If there is a previous
13508 // declaration of the same entity, the two will be linked via
13512 bool IsForwardReference = false;
13513 if (Kind == TTK_Enum) {
13514 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
13515 // enum X { A, B, C } D; D should chain to X.
13516 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name,
13517 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum,
13518 ScopedEnumUsesClassTag, !EnumUnderlying.isNull());
13520 if (isStdAlignValT && (!StdAlignValT || getStdAlignValT()->isImplicit()))
13521 StdAlignValT = cast<EnumDecl>(New);
13523 // If this is an undefined enum, warn.
13524 if (TUK != TUK_Definition && !Invalid) {
13526 if (!EnumUnderlyingIsImplicit &&
13527 (getLangOpts().CPlusPlus11 || getLangOpts().ObjC2) &&
13528 cast<EnumDecl>(New)->isFixed()) {
13529 // C++0x: 7.2p2: opaque-enum-declaration.
13530 // Conflicts are diagnosed above. Do nothing.
13532 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) {
13533 Diag(Loc, diag::ext_forward_ref_enum_def)
13535 Diag(Def->getLocation(), diag::note_previous_definition);
13537 unsigned DiagID = diag::ext_forward_ref_enum;
13538 if (getLangOpts().MSVCCompat)
13539 DiagID = diag::ext_ms_forward_ref_enum;
13540 else if (getLangOpts().CPlusPlus)
13541 DiagID = diag::err_forward_ref_enum;
13544 // If this is a forward-declared reference to an enumeration, make a
13545 // note of it; we won't actually be introducing the declaration into
13546 // the declaration context.
13547 if (TUK == TUK_Reference)
13548 IsForwardReference = true;
13552 if (EnumUnderlying) {
13553 EnumDecl *ED = cast<EnumDecl>(New);
13554 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
13555 ED->setIntegerTypeSourceInfo(TI);
13557 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
13558 ED->setPromotionType(ED->getIntegerType());
13561 // struct/union/class
13563 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
13564 // struct X { int A; } D; D should chain to X.
13565 if (getLangOpts().CPlusPlus) {
13566 // FIXME: Look for a way to use RecordDecl for simple structs.
13567 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
13568 cast_or_null<CXXRecordDecl>(PrevDecl));
13570 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit()))
13571 StdBadAlloc = cast<CXXRecordDecl>(New);
13573 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
13574 cast_or_null<RecordDecl>(PrevDecl));
13577 // C++11 [dcl.type]p3:
13578 // A type-specifier-seq shall not define a class or enumeration [...].
13579 if (getLangOpts().CPlusPlus && IsTypeSpecifier && TUK == TUK_Definition) {
13580 Diag(New->getLocation(), diag::err_type_defined_in_type_specifier)
13581 << Context.getTagDeclType(New);
13585 // Maybe add qualifier info.
13586 if (SS.isNotEmpty()) {
13588 // If this is either a declaration or a definition, check the
13589 // nested-name-specifier against the current context. We don't do this
13590 // for explicit specializations, because they have similar checking
13591 // (with more specific diagnostics) in the call to
13592 // CheckMemberSpecialization, below.
13593 if (!isMemberSpecialization &&
13594 (TUK == TUK_Definition || TUK == TUK_Declaration) &&
13595 diagnoseQualifiedDeclaration(SS, DC, OrigName, Loc))
13598 New->setQualifierInfo(SS.getWithLocInContext(Context));
13599 if (TemplateParameterLists.size() > 0) {
13600 New->setTemplateParameterListsInfo(Context, TemplateParameterLists);
13607 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) {
13608 // Add alignment attributes if necessary; these attributes are checked when
13609 // the ASTContext lays out the structure.
13611 // It is important for implementing the correct semantics that this
13612 // happen here (in act on tag decl). The #pragma pack stack is
13613 // maintained as a result of parser callbacks which can occur at
13614 // many points during the parsing of a struct declaration (because
13615 // the #pragma tokens are effectively skipped over during the
13616 // parsing of the struct).
13617 if (TUK == TUK_Definition) {
13618 AddAlignmentAttributesForRecord(RD);
13619 AddMsStructLayoutForRecord(RD);
13623 if (ModulePrivateLoc.isValid()) {
13624 if (isMemberSpecialization)
13625 Diag(New->getLocation(), diag::err_module_private_specialization)
13627 << FixItHint::CreateRemoval(ModulePrivateLoc);
13628 // __module_private__ does not apply to local classes. However, we only
13629 // diagnose this as an error when the declaration specifiers are
13630 // freestanding. Here, we just ignore the __module_private__.
13631 else if (!SearchDC->isFunctionOrMethod())
13632 New->setModulePrivate();
13635 // If this is a specialization of a member class (of a class template),
13636 // check the specialization.
13637 if (isMemberSpecialization && CheckMemberSpecialization(New, Previous))
13640 // If we're declaring or defining a tag in function prototype scope in C,
13641 // note that this type can only be used within the function and add it to
13642 // the list of decls to inject into the function definition scope.
13643 if ((Name || Kind == TTK_Enum) &&
13644 getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
13645 if (getLangOpts().CPlusPlus) {
13646 // C++ [dcl.fct]p6:
13647 // Types shall not be defined in return or parameter types.
13648 if (TUK == TUK_Definition && !IsTypeSpecifier) {
13649 Diag(Loc, diag::err_type_defined_in_param_type)
13653 } else if (!PrevDecl) {
13654 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
13659 New->setInvalidDecl();
13661 // Set the lexical context. If the tag has a C++ scope specifier, the
13662 // lexical context will be different from the semantic context.
13663 New->setLexicalDeclContext(CurContext);
13665 // Mark this as a friend decl if applicable.
13666 // In Microsoft mode, a friend declaration also acts as a forward
13667 // declaration so we always pass true to setObjectOfFriendDecl to make
13668 // the tag name visible.
13669 if (TUK == TUK_Friend)
13670 New->setObjectOfFriendDecl(getLangOpts().MSVCCompat);
13672 // Set the access specifier.
13673 if (!Invalid && SearchDC->isRecord())
13674 SetMemberAccessSpecifier(New, PrevDecl, AS);
13676 if (TUK == TUK_Definition)
13677 New->startDefinition();
13680 ProcessDeclAttributeList(S, New, Attr);
13681 AddPragmaAttributes(S, New);
13683 // If this has an identifier, add it to the scope stack.
13684 if (TUK == TUK_Friend) {
13685 // We might be replacing an existing declaration in the lookup tables;
13686 // if so, borrow its access specifier.
13688 New->setAccess(PrevDecl->getAccess());
13690 DeclContext *DC = New->getDeclContext()->getRedeclContext();
13691 DC->makeDeclVisibleInContext(New);
13692 if (Name) // can be null along some error paths
13693 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
13694 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false);
13696 S = getNonFieldDeclScope(S);
13697 PushOnScopeChains(New, S, !IsForwardReference);
13698 if (IsForwardReference)
13699 SearchDC->makeDeclVisibleInContext(New);
13701 CurContext->addDecl(New);
13704 // If this is the C FILE type, notify the AST context.
13705 if (IdentifierInfo *II = New->getIdentifier())
13706 if (!New->isInvalidDecl() &&
13707 New->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
13709 Context.setFILEDecl(New);
13712 mergeDeclAttributes(New, PrevDecl);
13714 // If there's a #pragma GCC visibility in scope, set the visibility of this
13716 AddPushedVisibilityAttribute(New);
13719 // In C++, don't return an invalid declaration. We can't recover well from
13720 // the cases where we make the type anonymous.
13721 if (Invalid && getLangOpts().CPlusPlus) {
13722 if (New->isBeingDefined())
13723 if (auto RD = dyn_cast<RecordDecl>(New))
13724 RD->completeDefinition();
13731 void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) {
13732 AdjustDeclIfTemplate(TagD);
13733 TagDecl *Tag = cast<TagDecl>(TagD);
13735 // Enter the tag context.
13736 PushDeclContext(S, Tag);
13738 ActOnDocumentableDecl(TagD);
13740 // If there's a #pragma GCC visibility in scope, set the visibility of this
13742 AddPushedVisibilityAttribute(Tag);
13745 Decl *Sema::ActOnObjCContainerStartDefinition(Decl *IDecl) {
13746 assert(isa<ObjCContainerDecl>(IDecl) &&
13747 "ActOnObjCContainerStartDefinition - Not ObjCContainerDecl");
13748 DeclContext *OCD = cast<DeclContext>(IDecl);
13749 assert(getContainingDC(OCD) == CurContext &&
13750 "The next DeclContext should be lexically contained in the current one.");
13755 void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD,
13756 SourceLocation FinalLoc,
13757 bool IsFinalSpelledSealed,
13758 SourceLocation LBraceLoc) {
13759 AdjustDeclIfTemplate(TagD);
13760 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD);
13762 FieldCollector->StartClass();
13764 if (!Record->getIdentifier())
13767 if (FinalLoc.isValid())
13768 Record->addAttr(new (Context)
13769 FinalAttr(FinalLoc, Context, IsFinalSpelledSealed));
13772 // [...] The class-name is also inserted into the scope of the
13773 // class itself; this is known as the injected-class-name. For
13774 // purposes of access checking, the injected-class-name is treated
13775 // as if it were a public member name.
13776 CXXRecordDecl *InjectedClassName
13777 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext,
13778 Record->getLocStart(), Record->getLocation(),
13779 Record->getIdentifier(),
13780 /*PrevDecl=*/nullptr,
13781 /*DelayTypeCreation=*/true);
13782 Context.getTypeDeclType(InjectedClassName, Record);
13783 InjectedClassName->setImplicit();
13784 InjectedClassName->setAccess(AS_public);
13785 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate())
13786 InjectedClassName->setDescribedClassTemplate(Template);
13787 PushOnScopeChains(InjectedClassName, S);
13788 assert(InjectedClassName->isInjectedClassName() &&
13789 "Broken injected-class-name");
13792 void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD,
13793 SourceRange BraceRange) {
13794 AdjustDeclIfTemplate(TagD);
13795 TagDecl *Tag = cast<TagDecl>(TagD);
13796 Tag->setBraceRange(BraceRange);
13798 // Make sure we "complete" the definition even it is invalid.
13799 if (Tag->isBeingDefined()) {
13800 assert(Tag->isInvalidDecl() && "We should already have completed it");
13801 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
13802 RD->completeDefinition();
13805 if (isa<CXXRecordDecl>(Tag)) {
13806 FieldCollector->FinishClass();
13809 // Exit this scope of this tag's definition.
13812 if (getCurLexicalContext()->isObjCContainer() &&
13813 Tag->getDeclContext()->isFileContext())
13814 Tag->setTopLevelDeclInObjCContainer();
13816 // Notify the consumer that we've defined a tag.
13817 if (!Tag->isInvalidDecl())
13818 Consumer.HandleTagDeclDefinition(Tag);
13821 void Sema::ActOnObjCContainerFinishDefinition() {
13822 // Exit this scope of this interface definition.
13826 void Sema::ActOnObjCTemporaryExitContainerContext(DeclContext *DC) {
13827 assert(DC == CurContext && "Mismatch of container contexts");
13828 OriginalLexicalContext = DC;
13829 ActOnObjCContainerFinishDefinition();
13832 void Sema::ActOnObjCReenterContainerContext(DeclContext *DC) {
13833 ActOnObjCContainerStartDefinition(cast<Decl>(DC));
13834 OriginalLexicalContext = nullptr;
13837 void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) {
13838 AdjustDeclIfTemplate(TagD);
13839 TagDecl *Tag = cast<TagDecl>(TagD);
13840 Tag->setInvalidDecl();
13842 // Make sure we "complete" the definition even it is invalid.
13843 if (Tag->isBeingDefined()) {
13844 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
13845 RD->completeDefinition();
13848 // We're undoing ActOnTagStartDefinition here, not
13849 // ActOnStartCXXMemberDeclarations, so we don't have to mess with
13850 // the FieldCollector.
13855 // Note that FieldName may be null for anonymous bitfields.
13856 ExprResult Sema::VerifyBitField(SourceLocation FieldLoc,
13857 IdentifierInfo *FieldName,
13858 QualType FieldTy, bool IsMsStruct,
13859 Expr *BitWidth, bool *ZeroWidth) {
13860 // Default to true; that shouldn't confuse checks for emptiness
13864 // C99 6.7.2.1p4 - verify the field type.
13865 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
13866 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) {
13867 // Handle incomplete types with specific error.
13868 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete))
13869 return ExprError();
13871 return Diag(FieldLoc, diag::err_not_integral_type_bitfield)
13872 << FieldName << FieldTy << BitWidth->getSourceRange();
13873 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield)
13874 << FieldTy << BitWidth->getSourceRange();
13875 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth),
13876 UPPC_BitFieldWidth))
13877 return ExprError();
13879 // If the bit-width is type- or value-dependent, don't try to check
13881 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent())
13884 llvm::APSInt Value;
13885 ExprResult ICE = VerifyIntegerConstantExpression(BitWidth, &Value);
13886 if (ICE.isInvalid())
13888 BitWidth = ICE.get();
13890 if (Value != 0 && ZeroWidth)
13891 *ZeroWidth = false;
13893 // Zero-width bitfield is ok for anonymous field.
13894 if (Value == 0 && FieldName)
13895 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName;
13897 if (Value.isSigned() && Value.isNegative()) {
13899 return Diag(FieldLoc, diag::err_bitfield_has_negative_width)
13900 << FieldName << Value.toString(10);
13901 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width)
13902 << Value.toString(10);
13905 if (!FieldTy->isDependentType()) {
13906 uint64_t TypeStorageSize = Context.getTypeSize(FieldTy);
13907 uint64_t TypeWidth = Context.getIntWidth(FieldTy);
13908 bool BitfieldIsOverwide = Value.ugt(TypeWidth);
13910 // Over-wide bitfields are an error in C or when using the MSVC bitfield
13912 bool CStdConstraintViolation =
13913 BitfieldIsOverwide && !getLangOpts().CPlusPlus;
13914 bool MSBitfieldViolation =
13915 Value.ugt(TypeStorageSize) &&
13916 (IsMsStruct || Context.getTargetInfo().getCXXABI().isMicrosoft());
13917 if (CStdConstraintViolation || MSBitfieldViolation) {
13918 unsigned DiagWidth =
13919 CStdConstraintViolation ? TypeWidth : TypeStorageSize;
13921 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_width)
13922 << FieldName << (unsigned)Value.getZExtValue()
13923 << !CStdConstraintViolation << DiagWidth;
13925 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_width)
13926 << (unsigned)Value.getZExtValue() << !CStdConstraintViolation
13930 // Warn on types where the user might conceivably expect to get all
13931 // specified bits as value bits: that's all integral types other than
13933 if (BitfieldIsOverwide && !FieldTy->isBooleanType()) {
13935 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_width)
13936 << FieldName << (unsigned)Value.getZExtValue()
13937 << (unsigned)TypeWidth;
13939 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_width)
13940 << (unsigned)Value.getZExtValue() << (unsigned)TypeWidth;
13947 /// ActOnField - Each field of a C struct/union is passed into this in order
13948 /// to create a FieldDecl object for it.
13949 Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
13950 Declarator &D, Expr *BitfieldWidth) {
13951 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD),
13952 DeclStart, D, static_cast<Expr*>(BitfieldWidth),
13953 /*InitStyle=*/ICIS_NoInit, AS_public);
13957 /// HandleField - Analyze a field of a C struct or a C++ data member.
13959 FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
13960 SourceLocation DeclStart,
13961 Declarator &D, Expr *BitWidth,
13962 InClassInitStyle InitStyle,
13963 AccessSpecifier AS) {
13964 if (D.isDecompositionDeclarator()) {
13965 const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
13966 Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
13967 << Decomp.getSourceRange();
13971 IdentifierInfo *II = D.getIdentifier();
13972 SourceLocation Loc = DeclStart;
13973 if (II) Loc = D.getIdentifierLoc();
13975 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13976 QualType T = TInfo->getType();
13977 if (getLangOpts().CPlusPlus) {
13978 CheckExtraCXXDefaultArguments(D);
13980 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
13981 UPPC_DataMemberType)) {
13982 D.setInvalidType();
13984 TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
13988 // TR 18037 does not allow fields to be declared with address spaces.
13989 if (T.getQualifiers().hasAddressSpace()) {
13990 Diag(Loc, diag::err_field_with_address_space);
13991 D.setInvalidType();
13994 // OpenCL v1.2 s6.9b,r & OpenCL v2.0 s6.12.5 - The following types cannot be
13995 // used as structure or union field: image, sampler, event or block types.
13996 if (LangOpts.OpenCL && (T->isEventT() || T->isImageType() ||
13997 T->isSamplerT() || T->isBlockPointerType())) {
13998 Diag(Loc, diag::err_opencl_type_struct_or_union_field) << T;
13999 D.setInvalidType();
14002 DiagnoseFunctionSpecifiers(D.getDeclSpec());
14004 if (D.getDeclSpec().isInlineSpecified())
14005 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
14006 << getLangOpts().CPlusPlus1z;
14007 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
14008 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
14009 diag::err_invalid_thread)
14010 << DeclSpec::getSpecifierName(TSCS);
14012 // Check to see if this name was declared as a member previously
14013 NamedDecl *PrevDecl = nullptr;
14014 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
14015 LookupName(Previous, S);
14016 switch (Previous.getResultKind()) {
14017 case LookupResult::Found:
14018 case LookupResult::FoundUnresolvedValue:
14019 PrevDecl = Previous.getAsSingle<NamedDecl>();
14022 case LookupResult::FoundOverloaded:
14023 PrevDecl = Previous.getRepresentativeDecl();
14026 case LookupResult::NotFound:
14027 case LookupResult::NotFoundInCurrentInstantiation:
14028 case LookupResult::Ambiguous:
14031 Previous.suppressDiagnostics();
14033 if (PrevDecl && PrevDecl->isTemplateParameter()) {
14034 // Maybe we will complain about the shadowed template parameter.
14035 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
14036 // Just pretend that we didn't see the previous declaration.
14037 PrevDecl = nullptr;
14040 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
14041 PrevDecl = nullptr;
14044 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable);
14045 SourceLocation TSSL = D.getLocStart();
14047 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, InitStyle,
14048 TSSL, AS, PrevDecl, &D);
14050 if (NewFD->isInvalidDecl())
14051 Record->setInvalidDecl();
14053 if (D.getDeclSpec().isModulePrivateSpecified())
14054 NewFD->setModulePrivate();
14056 if (NewFD->isInvalidDecl() && PrevDecl) {
14057 // Don't introduce NewFD into scope; there's already something
14058 // with the same name in the same scope.
14060 PushOnScopeChains(NewFD, S);
14062 Record->addDecl(NewFD);
14067 /// \brief Build a new FieldDecl and check its well-formedness.
14069 /// This routine builds a new FieldDecl given the fields name, type,
14070 /// record, etc. \p PrevDecl should refer to any previous declaration
14071 /// with the same name and in the same scope as the field to be
14074 /// \returns a new FieldDecl.
14076 /// \todo The Declarator argument is a hack. It will be removed once
14077 FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T,
14078 TypeSourceInfo *TInfo,
14079 RecordDecl *Record, SourceLocation Loc,
14080 bool Mutable, Expr *BitWidth,
14081 InClassInitStyle InitStyle,
14082 SourceLocation TSSL,
14083 AccessSpecifier AS, NamedDecl *PrevDecl,
14085 IdentifierInfo *II = Name.getAsIdentifierInfo();
14086 bool InvalidDecl = false;
14087 if (D) InvalidDecl = D->isInvalidType();
14089 // If we receive a broken type, recover by assuming 'int' and
14090 // marking this declaration as invalid.
14092 InvalidDecl = true;
14096 QualType EltTy = Context.getBaseElementType(T);
14097 if (!EltTy->isDependentType()) {
14098 if (RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) {
14099 // Fields of incomplete type force their record to be invalid.
14100 Record->setInvalidDecl();
14101 InvalidDecl = true;
14104 EltTy->isIncompleteType(&Def);
14105 if (Def && Def->isInvalidDecl()) {
14106 Record->setInvalidDecl();
14107 InvalidDecl = true;
14112 // OpenCL v1.2 s6.9.c: bitfields are not supported.
14113 if (BitWidth && getLangOpts().OpenCL) {
14114 Diag(Loc, diag::err_opencl_bitfields);
14115 InvalidDecl = true;
14118 // C99 6.7.2.1p8: A member of a structure or union may have any type other
14119 // than a variably modified type.
14120 if (!InvalidDecl && T->isVariablyModifiedType()) {
14121 bool SizeIsNegative;
14122 llvm::APSInt Oversized;
14124 TypeSourceInfo *FixedTInfo =
14125 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
14129 Diag(Loc, diag::warn_illegal_constant_array_size);
14130 TInfo = FixedTInfo;
14131 T = FixedTInfo->getType();
14133 if (SizeIsNegative)
14134 Diag(Loc, diag::err_typecheck_negative_array_size);
14135 else if (Oversized.getBoolValue())
14136 Diag(Loc, diag::err_array_too_large)
14137 << Oversized.toString(10);
14139 Diag(Loc, diag::err_typecheck_field_variable_size);
14140 InvalidDecl = true;
14144 // Fields can not have abstract class types
14145 if (!InvalidDecl && RequireNonAbstractType(Loc, T,
14146 diag::err_abstract_type_in_decl,
14147 AbstractFieldType))
14148 InvalidDecl = true;
14150 bool ZeroWidth = false;
14152 BitWidth = nullptr;
14153 // If this is declared as a bit-field, check the bit-field.
14155 BitWidth = VerifyBitField(Loc, II, T, Record->isMsStruct(Context), BitWidth,
14158 InvalidDecl = true;
14159 BitWidth = nullptr;
14164 // Check that 'mutable' is consistent with the type of the declaration.
14165 if (!InvalidDecl && Mutable) {
14166 unsigned DiagID = 0;
14167 if (T->isReferenceType())
14168 DiagID = getLangOpts().MSVCCompat ? diag::ext_mutable_reference
14169 : diag::err_mutable_reference;
14170 else if (T.isConstQualified())
14171 DiagID = diag::err_mutable_const;
14174 SourceLocation ErrLoc = Loc;
14175 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid())
14176 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc();
14177 Diag(ErrLoc, DiagID);
14178 if (DiagID != diag::ext_mutable_reference) {
14180 InvalidDecl = true;
14185 // C++11 [class.union]p8 (DR1460):
14186 // At most one variant member of a union may have a
14187 // brace-or-equal-initializer.
14188 if (InitStyle != ICIS_NoInit)
14189 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Record), Loc);
14191 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo,
14192 BitWidth, Mutable, InitStyle);
14194 NewFD->setInvalidDecl();
14196 if (PrevDecl && !isa<TagDecl>(PrevDecl)) {
14197 Diag(Loc, diag::err_duplicate_member) << II;
14198 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
14199 NewFD->setInvalidDecl();
14202 if (!InvalidDecl && getLangOpts().CPlusPlus) {
14203 if (Record->isUnion()) {
14204 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
14205 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl());
14206 if (RDecl->getDefinition()) {
14207 // C++ [class.union]p1: An object of a class with a non-trivial
14208 // constructor, a non-trivial copy constructor, a non-trivial
14209 // destructor, or a non-trivial copy assignment operator
14210 // cannot be a member of a union, nor can an array of such
14212 if (CheckNontrivialField(NewFD))
14213 NewFD->setInvalidDecl();
14217 // C++ [class.union]p1: If a union contains a member of reference type,
14218 // the program is ill-formed, except when compiling with MSVC extensions
14220 if (EltTy->isReferenceType()) {
14221 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
14222 diag::ext_union_member_of_reference_type :
14223 diag::err_union_member_of_reference_type)
14224 << NewFD->getDeclName() << EltTy;
14225 if (!getLangOpts().MicrosoftExt)
14226 NewFD->setInvalidDecl();
14231 // FIXME: We need to pass in the attributes given an AST
14232 // representation, not a parser representation.
14234 // FIXME: The current scope is almost... but not entirely... correct here.
14235 ProcessDeclAttributes(getCurScope(), NewFD, *D);
14237 if (NewFD->hasAttrs())
14238 CheckAlignasUnderalignment(NewFD);
14241 // In auto-retain/release, infer strong retension for fields of
14242 // retainable type.
14243 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewFD))
14244 NewFD->setInvalidDecl();
14246 if (T.isObjCGCWeak())
14247 Diag(Loc, diag::warn_attribute_weak_on_field);
14249 NewFD->setAccess(AS);
14253 bool Sema::CheckNontrivialField(FieldDecl *FD) {
14255 assert(getLangOpts().CPlusPlus && "valid check only for C++");
14257 if (FD->isInvalidDecl() || FD->getType()->isDependentType())
14260 QualType EltTy = Context.getBaseElementType(FD->getType());
14261 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
14262 CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl());
14263 if (RDecl->getDefinition()) {
14264 // We check for copy constructors before constructors
14265 // because otherwise we'll never get complaints about
14266 // copy constructors.
14268 CXXSpecialMember member = CXXInvalid;
14269 // We're required to check for any non-trivial constructors. Since the
14270 // implicit default constructor is suppressed if there are any
14271 // user-declared constructors, we just need to check that there is a
14272 // trivial default constructor and a trivial copy constructor. (We don't
14273 // worry about move constructors here, since this is a C++98 check.)
14274 if (RDecl->hasNonTrivialCopyConstructor())
14275 member = CXXCopyConstructor;
14276 else if (!RDecl->hasTrivialDefaultConstructor())
14277 member = CXXDefaultConstructor;
14278 else if (RDecl->hasNonTrivialCopyAssignment())
14279 member = CXXCopyAssignment;
14280 else if (RDecl->hasNonTrivialDestructor())
14281 member = CXXDestructor;
14283 if (member != CXXInvalid) {
14284 if (!getLangOpts().CPlusPlus11 &&
14285 getLangOpts().ObjCAutoRefCount && RDecl->hasObjectMember()) {
14286 // Objective-C++ ARC: it is an error to have a non-trivial field of
14287 // a union. However, system headers in Objective-C programs
14288 // occasionally have Objective-C lifetime objects within unions,
14289 // and rather than cause the program to fail, we make those
14290 // members unavailable.
14291 SourceLocation Loc = FD->getLocation();
14292 if (getSourceManager().isInSystemHeader(Loc)) {
14293 if (!FD->hasAttr<UnavailableAttr>())
14294 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
14295 UnavailableAttr::IR_ARCFieldWithOwnership, Loc));
14300 Diag(FD->getLocation(), getLangOpts().CPlusPlus11 ?
14301 diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member :
14302 diag::err_illegal_union_or_anon_struct_member)
14303 << FD->getParent()->isUnion() << FD->getDeclName() << member;
14304 DiagnoseNontrivial(RDecl, member);
14305 return !getLangOpts().CPlusPlus11;
14313 /// TranslateIvarVisibility - Translate visibility from a token ID to an
14314 /// AST enum value.
14315 static ObjCIvarDecl::AccessControl
14316 TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) {
14317 switch (ivarVisibility) {
14318 default: llvm_unreachable("Unknown visitibility kind");
14319 case tok::objc_private: return ObjCIvarDecl::Private;
14320 case tok::objc_public: return ObjCIvarDecl::Public;
14321 case tok::objc_protected: return ObjCIvarDecl::Protected;
14322 case tok::objc_package: return ObjCIvarDecl::Package;
14326 /// ActOnIvar - Each ivar field of an objective-c class is passed into this
14327 /// in order to create an IvarDecl object for it.
14328 Decl *Sema::ActOnIvar(Scope *S,
14329 SourceLocation DeclStart,
14330 Declarator &D, Expr *BitfieldWidth,
14331 tok::ObjCKeywordKind Visibility) {
14333 IdentifierInfo *II = D.getIdentifier();
14334 Expr *BitWidth = (Expr*)BitfieldWidth;
14335 SourceLocation Loc = DeclStart;
14336 if (II) Loc = D.getIdentifierLoc();
14338 // FIXME: Unnamed fields can be handled in various different ways, for
14339 // example, unnamed unions inject all members into the struct namespace!
14341 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
14342 QualType T = TInfo->getType();
14345 // 6.7.2.1p3, 6.7.2.1p4
14346 BitWidth = VerifyBitField(Loc, II, T, /*IsMsStruct*/false, BitWidth).get();
14348 D.setInvalidType();
14355 if (T->isReferenceType()) {
14356 Diag(Loc, diag::err_ivar_reference_type);
14357 D.setInvalidType();
14359 // C99 6.7.2.1p8: A member of a structure or union may have any type other
14360 // than a variably modified type.
14361 else if (T->isVariablyModifiedType()) {
14362 Diag(Loc, diag::err_typecheck_ivar_variable_size);
14363 D.setInvalidType();
14366 // Get the visibility (access control) for this ivar.
14367 ObjCIvarDecl::AccessControl ac =
14368 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility)
14369 : ObjCIvarDecl::None;
14370 // Must set ivar's DeclContext to its enclosing interface.
14371 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(CurContext);
14372 if (!EnclosingDecl || EnclosingDecl->isInvalidDecl())
14374 ObjCContainerDecl *EnclosingContext;
14375 if (ObjCImplementationDecl *IMPDecl =
14376 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
14377 if (LangOpts.ObjCRuntime.isFragile()) {
14378 // Case of ivar declared in an implementation. Context is that of its class.
14379 EnclosingContext = IMPDecl->getClassInterface();
14380 assert(EnclosingContext && "Implementation has no class interface!");
14383 EnclosingContext = EnclosingDecl;
14385 if (ObjCCategoryDecl *CDecl =
14386 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
14387 if (LangOpts.ObjCRuntime.isFragile() || !CDecl->IsClassExtension()) {
14388 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension();
14392 EnclosingContext = EnclosingDecl;
14395 // Construct the decl.
14396 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext,
14397 DeclStart, Loc, II, T,
14398 TInfo, ac, (Expr *)BitfieldWidth);
14401 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName,
14403 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S)
14404 && !isa<TagDecl>(PrevDecl)) {
14405 Diag(Loc, diag::err_duplicate_member) << II;
14406 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
14407 NewID->setInvalidDecl();
14411 // Process attributes attached to the ivar.
14412 ProcessDeclAttributes(S, NewID, D);
14414 if (D.isInvalidType())
14415 NewID->setInvalidDecl();
14417 // In ARC, infer 'retaining' for ivars of retainable type.
14418 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewID))
14419 NewID->setInvalidDecl();
14421 if (D.getDeclSpec().isModulePrivateSpecified())
14422 NewID->setModulePrivate();
14425 // FIXME: When interfaces are DeclContexts, we'll need to add
14426 // these to the interface.
14428 IdResolver.AddDecl(NewID);
14431 if (LangOpts.ObjCRuntime.isNonFragile() &&
14432 !NewID->isInvalidDecl() && isa<ObjCInterfaceDecl>(EnclosingDecl))
14433 Diag(Loc, diag::warn_ivars_in_interface);
14438 /// ActOnLastBitfield - This routine handles synthesized bitfields rules for
14439 /// class and class extensions. For every class \@interface and class
14440 /// extension \@interface, if the last ivar is a bitfield of any type,
14441 /// then add an implicit `char :0` ivar to the end of that interface.
14442 void Sema::ActOnLastBitfield(SourceLocation DeclLoc,
14443 SmallVectorImpl<Decl *> &AllIvarDecls) {
14444 if (LangOpts.ObjCRuntime.isFragile() || AllIvarDecls.empty())
14447 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1];
14448 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl);
14450 if (!Ivar->isBitField() || Ivar->getBitWidthValue(Context) == 0)
14452 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CurContext);
14454 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(CurContext)) {
14455 if (!CD->IsClassExtension())
14458 // No need to add this to end of @implementation.
14462 // All conditions are met. Add a new bitfield to the tail end of ivars.
14463 llvm::APInt Zero(Context.getTypeSize(Context.IntTy), 0);
14464 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.IntTy, DeclLoc);
14466 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(CurContext),
14467 DeclLoc, DeclLoc, nullptr,
14469 Context.getTrivialTypeSourceInfo(Context.CharTy,
14471 ObjCIvarDecl::Private, BW,
14473 AllIvarDecls.push_back(Ivar);
14476 void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
14477 ArrayRef<Decl *> Fields, SourceLocation LBrac,
14478 SourceLocation RBrac, AttributeList *Attr) {
14479 assert(EnclosingDecl && "missing record or interface decl");
14481 // If this is an Objective-C @implementation or category and we have
14482 // new fields here we should reset the layout of the interface since
14483 // it will now change.
14484 if (!Fields.empty() && isa<ObjCContainerDecl>(EnclosingDecl)) {
14485 ObjCContainerDecl *DC = cast<ObjCContainerDecl>(EnclosingDecl);
14486 switch (DC->getKind()) {
14488 case Decl::ObjCCategory:
14489 Context.ResetObjCLayout(cast<ObjCCategoryDecl>(DC)->getClassInterface());
14491 case Decl::ObjCImplementation:
14493 ResetObjCLayout(cast<ObjCImplementationDecl>(DC)->getClassInterface());
14498 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl);
14500 // Start counting up the number of named members; make sure to include
14501 // members of anonymous structs and unions in the total.
14502 unsigned NumNamedMembers = 0;
14504 for (const auto *I : Record->decls()) {
14505 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
14506 if (IFD->getDeclName())
14511 // Verify that all the fields are okay.
14512 SmallVector<FieldDecl*, 32> RecFields;
14514 bool ObjCFieldLifetimeErrReported = false;
14515 for (ArrayRef<Decl *>::iterator i = Fields.begin(), end = Fields.end();
14517 FieldDecl *FD = cast<FieldDecl>(*i);
14519 // Get the type for the field.
14520 const Type *FDTy = FD->getType().getTypePtr();
14522 if (!FD->isAnonymousStructOrUnion()) {
14523 // Remember all fields written by the user.
14524 RecFields.push_back(FD);
14527 // If the field is already invalid for some reason, don't emit more
14528 // diagnostics about it.
14529 if (FD->isInvalidDecl()) {
14530 EnclosingDecl->setInvalidDecl();
14535 // A structure or union shall not contain a member with
14536 // incomplete or function type (hence, a structure shall not
14537 // contain an instance of itself, but may contain a pointer to
14538 // an instance of itself), except that the last member of a
14539 // structure with more than one named member may have incomplete
14540 // array type; such a structure (and any union containing,
14541 // possibly recursively, a member that is such a structure)
14542 // shall not be a member of a structure or an element of an
14544 if (FDTy->isFunctionType()) {
14545 // Field declared as a function.
14546 Diag(FD->getLocation(), diag::err_field_declared_as_function)
14547 << FD->getDeclName();
14548 FD->setInvalidDecl();
14549 EnclosingDecl->setInvalidDecl();
14551 } else if (FDTy->isIncompleteArrayType() && Record &&
14552 ((i + 1 == Fields.end() && !Record->isUnion()) ||
14553 ((getLangOpts().MicrosoftExt ||
14554 getLangOpts().CPlusPlus) &&
14555 (i + 1 == Fields.end() || Record->isUnion())))) {
14556 // Flexible array member.
14557 // Microsoft and g++ is more permissive regarding flexible array.
14558 // It will accept flexible array in union and also
14559 // as the sole element of a struct/class.
14560 unsigned DiagID = 0;
14561 if (Record->isUnion())
14562 DiagID = getLangOpts().MicrosoftExt
14563 ? diag::ext_flexible_array_union_ms
14564 : getLangOpts().CPlusPlus
14565 ? diag::ext_flexible_array_union_gnu
14566 : diag::err_flexible_array_union;
14567 else if (NumNamedMembers < 1)
14568 DiagID = getLangOpts().MicrosoftExt
14569 ? diag::ext_flexible_array_empty_aggregate_ms
14570 : getLangOpts().CPlusPlus
14571 ? diag::ext_flexible_array_empty_aggregate_gnu
14572 : diag::err_flexible_array_empty_aggregate;
14575 Diag(FD->getLocation(), DiagID) << FD->getDeclName()
14576 << Record->getTagKind();
14577 // While the layout of types that contain virtual bases is not specified
14578 // by the C++ standard, both the Itanium and Microsoft C++ ABIs place
14579 // virtual bases after the derived members. This would make a flexible
14580 // array member declared at the end of an object not adjacent to the end
14582 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record))
14583 if (RD->getNumVBases() != 0)
14584 Diag(FD->getLocation(), diag::err_flexible_array_virtual_base)
14585 << FD->getDeclName() << Record->getTagKind();
14586 if (!getLangOpts().C99)
14587 Diag(FD->getLocation(), diag::ext_c99_flexible_array_member)
14588 << FD->getDeclName() << Record->getTagKind();
14590 // If the element type has a non-trivial destructor, we would not
14591 // implicitly destroy the elements, so disallow it for now.
14593 // FIXME: GCC allows this. We should probably either implicitly delete
14594 // the destructor of the containing class, or just allow this.
14595 QualType BaseElem = Context.getBaseElementType(FD->getType());
14596 if (!BaseElem->isDependentType() && BaseElem.isDestructedType()) {
14597 Diag(FD->getLocation(), diag::err_flexible_array_has_nontrivial_dtor)
14598 << FD->getDeclName() << FD->getType();
14599 FD->setInvalidDecl();
14600 EnclosingDecl->setInvalidDecl();
14603 // Okay, we have a legal flexible array member at the end of the struct.
14604 Record->setHasFlexibleArrayMember(true);
14605 } else if (!FDTy->isDependentType() &&
14606 RequireCompleteType(FD->getLocation(), FD->getType(),
14607 diag::err_field_incomplete)) {
14609 FD->setInvalidDecl();
14610 EnclosingDecl->setInvalidDecl();
14612 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) {
14613 if (Record && FDTTy->getDecl()->hasFlexibleArrayMember()) {
14614 // A type which contains a flexible array member is considered to be a
14615 // flexible array member.
14616 Record->setHasFlexibleArrayMember(true);
14617 if (!Record->isUnion()) {
14618 // If this is a struct/class and this is not the last element, reject
14619 // it. Note that GCC supports variable sized arrays in the middle of
14621 if (i + 1 != Fields.end())
14622 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct)
14623 << FD->getDeclName() << FD->getType();
14625 // We support flexible arrays at the end of structs in
14626 // other structs as an extension.
14627 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct)
14628 << FD->getDeclName();
14632 if (isa<ObjCContainerDecl>(EnclosingDecl) &&
14633 RequireNonAbstractType(FD->getLocation(), FD->getType(),
14634 diag::err_abstract_type_in_decl,
14635 AbstractIvarType)) {
14636 // Ivars can not have abstract class types
14637 FD->setInvalidDecl();
14639 if (Record && FDTTy->getDecl()->hasObjectMember())
14640 Record->setHasObjectMember(true);
14641 if (Record && FDTTy->getDecl()->hasVolatileMember())
14642 Record->setHasVolatileMember(true);
14643 } else if (FDTy->isObjCObjectType()) {
14644 /// A field cannot be an Objective-c object
14645 Diag(FD->getLocation(), diag::err_statically_allocated_object)
14646 << FixItHint::CreateInsertion(FD->getLocation(), "*");
14647 QualType T = Context.getObjCObjectPointerType(FD->getType());
14649 } else if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
14650 Record && !ObjCFieldLifetimeErrReported &&
14651 (!getLangOpts().CPlusPlus || Record->isUnion())) {
14652 // It's an error in ARC or Weak if a field has lifetime.
14653 // We don't want to report this in a system header, though,
14654 // so we just make the field unavailable.
14655 // FIXME: that's really not sufficient; we need to make the type
14656 // itself invalid to, say, initialize or copy.
14657 QualType T = FD->getType();
14658 if (T.hasNonTrivialObjCLifetime()) {
14659 SourceLocation loc = FD->getLocation();
14660 if (getSourceManager().isInSystemHeader(loc)) {
14661 if (!FD->hasAttr<UnavailableAttr>()) {
14662 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
14663 UnavailableAttr::IR_ARCFieldWithOwnership, loc));
14666 Diag(FD->getLocation(), diag::err_arc_objc_object_in_tag)
14667 << T->isBlockPointerType() << Record->getTagKind();
14669 ObjCFieldLifetimeErrReported = true;
14671 } else if (getLangOpts().ObjC1 &&
14672 getLangOpts().getGC() != LangOptions::NonGC &&
14673 Record && !Record->hasObjectMember()) {
14674 if (FD->getType()->isObjCObjectPointerType() ||
14675 FD->getType().isObjCGCStrong())
14676 Record->setHasObjectMember(true);
14677 else if (Context.getAsArrayType(FD->getType())) {
14678 QualType BaseType = Context.getBaseElementType(FD->getType());
14679 if (BaseType->isRecordType() &&
14680 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember())
14681 Record->setHasObjectMember(true);
14682 else if (BaseType->isObjCObjectPointerType() ||
14683 BaseType.isObjCGCStrong())
14684 Record->setHasObjectMember(true);
14687 if (Record && FD->getType().isVolatileQualified())
14688 Record->setHasVolatileMember(true);
14689 // Keep track of the number of named members.
14690 if (FD->getIdentifier())
14694 // Okay, we successfully defined 'Record'.
14696 bool Completed = false;
14697 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
14698 if (!CXXRecord->isInvalidDecl()) {
14699 // Set access bits correctly on the directly-declared conversions.
14700 for (CXXRecordDecl::conversion_iterator
14701 I = CXXRecord->conversion_begin(),
14702 E = CXXRecord->conversion_end(); I != E; ++I)
14703 I.setAccess((*I)->getAccess());
14706 if (!CXXRecord->isDependentType()) {
14707 if (CXXRecord->hasUserDeclaredDestructor()) {
14708 // Adjust user-defined destructor exception spec.
14709 if (getLangOpts().CPlusPlus11)
14710 AdjustDestructorExceptionSpec(CXXRecord,
14711 CXXRecord->getDestructor());
14714 if (!CXXRecord->isInvalidDecl()) {
14715 // Add any implicitly-declared members to this class.
14716 AddImplicitlyDeclaredMembersToClass(CXXRecord);
14718 // If we have virtual base classes, we may end up finding multiple
14719 // final overriders for a given virtual function. Check for this
14721 if (CXXRecord->getNumVBases()) {
14722 CXXFinalOverriderMap FinalOverriders;
14723 CXXRecord->getFinalOverriders(FinalOverriders);
14725 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
14726 MEnd = FinalOverriders.end();
14728 for (OverridingMethods::iterator SO = M->second.begin(),
14729 SOEnd = M->second.end();
14730 SO != SOEnd; ++SO) {
14731 assert(SO->second.size() > 0 &&
14732 "Virtual function without overridding functions?");
14733 if (SO->second.size() == 1)
14736 // C++ [class.virtual]p2:
14737 // In a derived class, if a virtual member function of a base
14738 // class subobject has more than one final overrider the
14739 // program is ill-formed.
14740 Diag(Record->getLocation(), diag::err_multiple_final_overriders)
14741 << (const NamedDecl *)M->first << Record;
14742 Diag(M->first->getLocation(),
14743 diag::note_overridden_virtual_function);
14744 for (OverridingMethods::overriding_iterator
14745 OM = SO->second.begin(),
14746 OMEnd = SO->second.end();
14748 Diag(OM->Method->getLocation(), diag::note_final_overrider)
14749 << (const NamedDecl *)M->first << OM->Method->getParent();
14751 Record->setInvalidDecl();
14754 CXXRecord->completeDefinition(&FinalOverriders);
14762 Record->completeDefinition();
14764 // We may have deferred checking for a deleted destructor. Check now.
14765 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
14766 auto *Dtor = CXXRecord->getDestructor();
14767 if (Dtor && Dtor->isImplicit() &&
14768 ShouldDeleteSpecialMember(Dtor, CXXDestructor))
14769 SetDeclDeleted(Dtor, CXXRecord->getLocation());
14772 if (Record->hasAttrs()) {
14773 CheckAlignasUnderalignment(Record);
14775 if (const MSInheritanceAttr *IA = Record->getAttr<MSInheritanceAttr>())
14776 checkMSInheritanceAttrOnDefinition(cast<CXXRecordDecl>(Record),
14777 IA->getRange(), IA->getBestCase(),
14778 IA->getSemanticSpelling());
14781 // Check if the structure/union declaration is a type that can have zero
14782 // size in C. For C this is a language extension, for C++ it may cause
14783 // compatibility problems.
14784 bool CheckForZeroSize;
14785 if (!getLangOpts().CPlusPlus) {
14786 CheckForZeroSize = true;
14788 // For C++ filter out types that cannot be referenced in C code.
14789 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record);
14791 CXXRecord->getLexicalDeclContext()->isExternCContext() &&
14792 !CXXRecord->isDependentType() &&
14793 CXXRecord->isCLike();
14795 if (CheckForZeroSize) {
14796 bool ZeroSize = true;
14797 bool IsEmpty = true;
14798 unsigned NonBitFields = 0;
14799 for (RecordDecl::field_iterator I = Record->field_begin(),
14800 E = Record->field_end();
14801 (NonBitFields == 0 || ZeroSize) && I != E; ++I) {
14803 if (I->isUnnamedBitfield()) {
14804 if (I->getBitWidthValue(Context) > 0)
14808 QualType FieldType = I->getType();
14809 if (FieldType->isIncompleteType() ||
14810 !Context.getTypeSizeInChars(FieldType).isZero())
14815 // Empty structs are an extension in C (C99 6.7.2.1p7). They are
14816 // allowed in C++, but warn if its declaration is inside
14817 // extern "C" block.
14819 Diag(RecLoc, getLangOpts().CPlusPlus ?
14820 diag::warn_zero_size_struct_union_in_extern_c :
14821 diag::warn_zero_size_struct_union_compat)
14822 << IsEmpty << Record->isUnion() << (NonBitFields > 1);
14825 // Structs without named members are extension in C (C99 6.7.2.1p7),
14826 // but are accepted by GCC.
14827 if (NonBitFields == 0 && !getLangOpts().CPlusPlus) {
14828 Diag(RecLoc, IsEmpty ? diag::ext_empty_struct_union :
14829 diag::ext_no_named_members_in_struct_union)
14830 << Record->isUnion();
14834 ObjCIvarDecl **ClsFields =
14835 reinterpret_cast<ObjCIvarDecl**>(RecFields.data());
14836 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) {
14837 ID->setEndOfDefinitionLoc(RBrac);
14838 // Add ivar's to class's DeclContext.
14839 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
14840 ClsFields[i]->setLexicalDeclContext(ID);
14841 ID->addDecl(ClsFields[i]);
14843 // Must enforce the rule that ivars in the base classes may not be
14845 if (ID->getSuperClass())
14846 DiagnoseDuplicateIvars(ID, ID->getSuperClass());
14847 } else if (ObjCImplementationDecl *IMPDecl =
14848 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
14849 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl");
14850 for (unsigned I = 0, N = RecFields.size(); I != N; ++I)
14851 // Ivar declared in @implementation never belongs to the implementation.
14852 // Only it is in implementation's lexical context.
14853 ClsFields[I]->setLexicalDeclContext(IMPDecl);
14854 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac);
14855 IMPDecl->setIvarLBraceLoc(LBrac);
14856 IMPDecl->setIvarRBraceLoc(RBrac);
14857 } else if (ObjCCategoryDecl *CDecl =
14858 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
14859 // case of ivars in class extension; all other cases have been
14860 // reported as errors elsewhere.
14861 // FIXME. Class extension does not have a LocEnd field.
14862 // CDecl->setLocEnd(RBrac);
14863 // Add ivar's to class extension's DeclContext.
14864 // Diagnose redeclaration of private ivars.
14865 ObjCInterfaceDecl *IDecl = CDecl->getClassInterface();
14866 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
14868 if (const ObjCIvarDecl *ClsIvar =
14869 IDecl->getIvarDecl(ClsFields[i]->getIdentifier())) {
14870 Diag(ClsFields[i]->getLocation(),
14871 diag::err_duplicate_ivar_declaration);
14872 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
14875 for (const auto *Ext : IDecl->known_extensions()) {
14876 if (const ObjCIvarDecl *ClsExtIvar
14877 = Ext->getIvarDecl(ClsFields[i]->getIdentifier())) {
14878 Diag(ClsFields[i]->getLocation(),
14879 diag::err_duplicate_ivar_declaration);
14880 Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
14885 ClsFields[i]->setLexicalDeclContext(CDecl);
14886 CDecl->addDecl(ClsFields[i]);
14888 CDecl->setIvarLBraceLoc(LBrac);
14889 CDecl->setIvarRBraceLoc(RBrac);
14894 ProcessDeclAttributeList(S, Record, Attr);
14897 /// \brief Determine whether the given integral value is representable within
14898 /// the given type T.
14899 static bool isRepresentableIntegerValue(ASTContext &Context,
14900 llvm::APSInt &Value,
14902 assert(T->isIntegralType(Context) && "Integral type required!");
14903 unsigned BitWidth = Context.getIntWidth(T);
14905 if (Value.isUnsigned() || Value.isNonNegative()) {
14906 if (T->isSignedIntegerOrEnumerationType())
14908 return Value.getActiveBits() <= BitWidth;
14910 return Value.getMinSignedBits() <= BitWidth;
14913 // \brief Given an integral type, return the next larger integral type
14914 // (or a NULL type of no such type exists).
14915 static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) {
14916 // FIXME: Int128/UInt128 support, which also needs to be introduced into
14917 // enum checking below.
14918 assert(T->isIntegralType(Context) && "Integral type required!");
14919 const unsigned NumTypes = 4;
14920 QualType SignedIntegralTypes[NumTypes] = {
14921 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy
14923 QualType UnsignedIntegralTypes[NumTypes] = {
14924 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy,
14925 Context.UnsignedLongLongTy
14928 unsigned BitWidth = Context.getTypeSize(T);
14929 QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes
14930 : UnsignedIntegralTypes;
14931 for (unsigned I = 0; I != NumTypes; ++I)
14932 if (Context.getTypeSize(Types[I]) > BitWidth)
14938 EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum,
14939 EnumConstantDecl *LastEnumConst,
14940 SourceLocation IdLoc,
14941 IdentifierInfo *Id,
14943 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
14944 llvm::APSInt EnumVal(IntWidth);
14947 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue))
14951 Val = DefaultLvalueConversion(Val).get();
14954 if (Enum->isDependentType() || Val->isTypeDependent())
14955 EltTy = Context.DependentTy;
14957 SourceLocation ExpLoc;
14958 if (getLangOpts().CPlusPlus11 && Enum->isFixed() &&
14959 !getLangOpts().MSVCCompat) {
14960 // C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the
14961 // constant-expression in the enumerator-definition shall be a converted
14962 // constant expression of the underlying type.
14963 EltTy = Enum->getIntegerType();
14964 ExprResult Converted =
14965 CheckConvertedConstantExpression(Val, EltTy, EnumVal,
14967 if (Converted.isInvalid())
14970 Val = Converted.get();
14971 } else if (!Val->isValueDependent() &&
14972 !(Val = VerifyIntegerConstantExpression(Val,
14973 &EnumVal).get())) {
14974 // C99 6.7.2.2p2: Make sure we have an integer constant expression.
14976 if (Enum->isFixed()) {
14977 EltTy = Enum->getIntegerType();
14979 // In Obj-C and Microsoft mode, require the enumeration value to be
14980 // representable in the underlying type of the enumeration. In C++11,
14981 // we perform a non-narrowing conversion as part of converted constant
14982 // expression checking.
14983 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
14984 if (getLangOpts().MSVCCompat) {
14985 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy;
14986 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
14988 Diag(IdLoc, diag::err_enumerator_too_large) << EltTy;
14990 Val = ImpCastExprToType(Val, EltTy,
14991 EltTy->isBooleanType() ?
14992 CK_IntegralToBoolean : CK_IntegralCast)
14994 } else if (getLangOpts().CPlusPlus) {
14995 // C++11 [dcl.enum]p5:
14996 // If the underlying type is not fixed, the type of each enumerator
14997 // is the type of its initializing value:
14998 // - If an initializer is specified for an enumerator, the
14999 // initializing value has the same type as the expression.
15000 EltTy = Val->getType();
15003 // The expression that defines the value of an enumeration constant
15004 // shall be an integer constant expression that has a value
15005 // representable as an int.
15007 // Complain if the value is not representable in an int.
15008 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy))
15009 Diag(IdLoc, diag::ext_enum_value_not_int)
15010 << EnumVal.toString(10) << Val->getSourceRange()
15011 << (EnumVal.isUnsigned() || EnumVal.isNonNegative());
15012 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) {
15013 // Force the type of the expression to 'int'.
15014 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).get();
15016 EltTy = Val->getType();
15023 if (Enum->isDependentType())
15024 EltTy = Context.DependentTy;
15025 else if (!LastEnumConst) {
15026 // C++0x [dcl.enum]p5:
15027 // If the underlying type is not fixed, the type of each enumerator
15028 // is the type of its initializing value:
15029 // - If no initializer is specified for the first enumerator, the
15030 // initializing value has an unspecified integral type.
15032 // GCC uses 'int' for its unspecified integral type, as does
15034 if (Enum->isFixed()) {
15035 EltTy = Enum->getIntegerType();
15038 EltTy = Context.IntTy;
15041 // Assign the last value + 1.
15042 EnumVal = LastEnumConst->getInitVal();
15044 EltTy = LastEnumConst->getType();
15046 // Check for overflow on increment.
15047 if (EnumVal < LastEnumConst->getInitVal()) {
15048 // C++0x [dcl.enum]p5:
15049 // If the underlying type is not fixed, the type of each enumerator
15050 // is the type of its initializing value:
15052 // - Otherwise the type of the initializing value is the same as
15053 // the type of the initializing value of the preceding enumerator
15054 // unless the incremented value is not representable in that type,
15055 // in which case the type is an unspecified integral type
15056 // sufficient to contain the incremented value. If no such type
15057 // exists, the program is ill-formed.
15058 QualType T = getNextLargerIntegralType(Context, EltTy);
15059 if (T.isNull() || Enum->isFixed()) {
15060 // There is no integral type larger enough to represent this
15061 // value. Complain, then allow the value to wrap around.
15062 EnumVal = LastEnumConst->getInitVal();
15063 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2);
15065 if (Enum->isFixed())
15066 // When the underlying type is fixed, this is ill-formed.
15067 Diag(IdLoc, diag::err_enumerator_wrapped)
15068 << EnumVal.toString(10)
15071 Diag(IdLoc, diag::ext_enumerator_increment_too_large)
15072 << EnumVal.toString(10);
15077 // Retrieve the last enumerator's value, extent that type to the
15078 // type that is supposed to be large enough to represent the incremented
15079 // value, then increment.
15080 EnumVal = LastEnumConst->getInitVal();
15081 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
15082 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy));
15085 // If we're not in C++, diagnose the overflow of enumerator values,
15086 // which in C99 means that the enumerator value is not representable in
15087 // an int (C99 6.7.2.2p2). However, we support GCC's extension that
15088 // permits enumerator values that are representable in some larger
15090 if (!getLangOpts().CPlusPlus && !T.isNull())
15091 Diag(IdLoc, diag::warn_enum_value_overflow);
15092 } else if (!getLangOpts().CPlusPlus &&
15093 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
15094 // Enforce C99 6.7.2.2p2 even when we compute the next value.
15095 Diag(IdLoc, diag::ext_enum_value_not_int)
15096 << EnumVal.toString(10) << 1;
15101 if (!EltTy->isDependentType()) {
15102 // Make the enumerator value match the signedness and size of the
15103 // enumerator's type.
15104 EnumVal = EnumVal.extOrTrunc(Context.getIntWidth(EltTy));
15105 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
15108 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy,
15112 Sema::SkipBodyInfo Sema::shouldSkipAnonEnumBody(Scope *S, IdentifierInfo *II,
15113 SourceLocation IILoc) {
15114 if (!(getLangOpts().Modules || getLangOpts().ModulesLocalVisibility) ||
15115 !getLangOpts().CPlusPlus)
15116 return SkipBodyInfo();
15118 // We have an anonymous enum definition. Look up the first enumerator to
15119 // determine if we should merge the definition with an existing one and
15121 NamedDecl *PrevDecl = LookupSingleName(S, II, IILoc, LookupOrdinaryName,
15123 auto *PrevECD = dyn_cast_or_null<EnumConstantDecl>(PrevDecl);
15125 return SkipBodyInfo();
15127 EnumDecl *PrevED = cast<EnumDecl>(PrevECD->getDeclContext());
15129 if (!PrevED->getDeclName() && !hasVisibleDefinition(PrevED, &Hidden)) {
15131 Skip.Previous = Hidden;
15135 return SkipBodyInfo();
15138 Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst,
15139 SourceLocation IdLoc, IdentifierInfo *Id,
15140 AttributeList *Attr,
15141 SourceLocation EqualLoc, Expr *Val) {
15142 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl);
15143 EnumConstantDecl *LastEnumConst =
15144 cast_or_null<EnumConstantDecl>(lastEnumConst);
15146 // The scope passed in may not be a decl scope. Zip up the scope tree until
15147 // we find one that is.
15148 S = getNonFieldDeclScope(S);
15150 // Verify that there isn't already something declared with this name in this
15152 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName,
15154 if (PrevDecl && PrevDecl->isTemplateParameter()) {
15155 // Maybe we will complain about the shadowed template parameter.
15156 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl);
15157 // Just pretend that we didn't see the previous declaration.
15158 PrevDecl = nullptr;
15161 // C++ [class.mem]p15:
15162 // If T is the name of a class, then each of the following shall have a name
15163 // different from T:
15164 // - every enumerator of every member of class T that is an unscoped
15166 if (!TheEnumDecl->isScoped())
15167 DiagnoseClassNameShadow(TheEnumDecl->getDeclContext(),
15168 DeclarationNameInfo(Id, IdLoc));
15170 EnumConstantDecl *New =
15171 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val);
15176 // When in C++, we may get a TagDecl with the same name; in this case the
15177 // enum constant will 'hide' the tag.
15178 assert((getLangOpts().CPlusPlus || !isa<TagDecl>(PrevDecl)) &&
15179 "Received TagDecl when not in C++!");
15180 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S) &&
15181 shouldLinkPossiblyHiddenDecl(PrevDecl, New)) {
15182 if (isa<EnumConstantDecl>(PrevDecl))
15183 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id;
15185 Diag(IdLoc, diag::err_redefinition) << Id;
15186 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
15191 // Process attributes.
15192 if (Attr) ProcessDeclAttributeList(S, New, Attr);
15193 AddPragmaAttributes(S, New);
15195 // Register this decl in the current scope stack.
15196 New->setAccess(TheEnumDecl->getAccess());
15197 PushOnScopeChains(New, S);
15199 ActOnDocumentableDecl(New);
15204 // Returns true when the enum initial expression does not trigger the
15205 // duplicate enum warning. A few common cases are exempted as follows:
15206 // Element2 = Element1
15207 // Element2 = Element1 + 1
15208 // Element2 = Element1 - 1
15209 // Where Element2 and Element1 are from the same enum.
15210 static bool ValidDuplicateEnum(EnumConstantDecl *ECD, EnumDecl *Enum) {
15211 Expr *InitExpr = ECD->getInitExpr();
15214 InitExpr = InitExpr->IgnoreImpCasts();
15216 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(InitExpr)) {
15217 if (!BO->isAdditiveOp())
15219 IntegerLiteral *IL = dyn_cast<IntegerLiteral>(BO->getRHS());
15222 if (IL->getValue() != 1)
15225 InitExpr = BO->getLHS();
15228 // This checks if the elements are from the same enum.
15229 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InitExpr);
15233 EnumConstantDecl *EnumConstant = dyn_cast<EnumConstantDecl>(DRE->getDecl());
15237 if (cast<EnumDecl>(TagDecl::castFromDeclContext(ECD->getDeclContext())) !=
15247 bool isTombstoneOrEmptyKey;
15248 DupKey(int64_t val, bool isTombstoneOrEmptyKey)
15249 : val(val), isTombstoneOrEmptyKey(isTombstoneOrEmptyKey) {}
15252 static DupKey GetDupKey(const llvm::APSInt& Val) {
15253 return DupKey(Val.isSigned() ? Val.getSExtValue() : Val.getZExtValue(),
15257 struct DenseMapInfoDupKey {
15258 static DupKey getEmptyKey() { return DupKey(0, true); }
15259 static DupKey getTombstoneKey() { return DupKey(1, true); }
15260 static unsigned getHashValue(const DupKey Key) {
15261 return (unsigned)(Key.val * 37);
15263 static bool isEqual(const DupKey& LHS, const DupKey& RHS) {
15264 return LHS.isTombstoneOrEmptyKey == RHS.isTombstoneOrEmptyKey &&
15265 LHS.val == RHS.val;
15268 } // end anonymous namespace
15270 // Emits a warning when an element is implicitly set a value that
15271 // a previous element has already been set to.
15272 static void CheckForDuplicateEnumValues(Sema &S, ArrayRef<Decl *> Elements,
15274 QualType EnumType) {
15275 if (S.Diags.isIgnored(diag::warn_duplicate_enum_values, Enum->getLocation()))
15277 // Avoid anonymous enums
15278 if (!Enum->getIdentifier())
15281 // Only check for small enums.
15282 if (Enum->getNumPositiveBits() > 63 || Enum->getNumNegativeBits() > 64)
15285 typedef SmallVector<EnumConstantDecl *, 3> ECDVector;
15286 typedef SmallVector<ECDVector *, 3> DuplicatesVector;
15288 typedef llvm::PointerUnion<EnumConstantDecl*, ECDVector*> DeclOrVector;
15289 typedef llvm::DenseMap<DupKey, DeclOrVector, DenseMapInfoDupKey>
15292 DuplicatesVector DupVector;
15293 ValueToVectorMap EnumMap;
15295 // Populate the EnumMap with all values represented by enum constants without
15297 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15298 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]);
15300 // Null EnumConstantDecl means a previous diagnostic has been emitted for
15301 // this constant. Skip this enum since it may be ill-formed.
15306 if (ECD->getInitExpr())
15309 DupKey Key = GetDupKey(ECD->getInitVal());
15310 DeclOrVector &Entry = EnumMap[Key];
15312 // First time encountering this value.
15313 if (Entry.isNull())
15317 // Create vectors for any values that has duplicates.
15318 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15319 EnumConstantDecl *ECD = cast<EnumConstantDecl>(Elements[i]);
15320 if (!ValidDuplicateEnum(ECD, Enum))
15323 DupKey Key = GetDupKey(ECD->getInitVal());
15325 DeclOrVector& Entry = EnumMap[Key];
15326 if (Entry.isNull())
15329 if (EnumConstantDecl *D = Entry.dyn_cast<EnumConstantDecl*>()) {
15330 // Ensure constants are different.
15334 // Create new vector and push values onto it.
15335 ECDVector *Vec = new ECDVector();
15337 Vec->push_back(ECD);
15339 // Update entry to point to the duplicates vector.
15342 // Store the vector somewhere we can consult later for quick emission of
15344 DupVector.push_back(Vec);
15348 ECDVector *Vec = Entry.get<ECDVector*>();
15349 // Make sure constants are not added more than once.
15350 if (*Vec->begin() == ECD)
15353 Vec->push_back(ECD);
15356 // Emit diagnostics.
15357 for (DuplicatesVector::iterator DupVectorIter = DupVector.begin(),
15358 DupVectorEnd = DupVector.end();
15359 DupVectorIter != DupVectorEnd; ++DupVectorIter) {
15360 ECDVector *Vec = *DupVectorIter;
15361 assert(Vec->size() > 1 && "ECDVector should have at least 2 elements.");
15363 // Emit warning for one enum constant.
15364 ECDVector::iterator I = Vec->begin();
15365 S.Diag((*I)->getLocation(), diag::warn_duplicate_enum_values)
15366 << (*I)->getName() << (*I)->getInitVal().toString(10)
15367 << (*I)->getSourceRange();
15370 // Emit one note for each of the remaining enum constants with
15372 for (ECDVector::iterator E = Vec->end(); I != E; ++I)
15373 S.Diag((*I)->getLocation(), diag::note_duplicate_element)
15374 << (*I)->getName() << (*I)->getInitVal().toString(10)
15375 << (*I)->getSourceRange();
15380 bool Sema::IsValueInFlagEnum(const EnumDecl *ED, const llvm::APInt &Val,
15381 bool AllowMask) const {
15382 assert(ED->isClosedFlag() && "looking for value in non-flag or open enum");
15383 assert(ED->isCompleteDefinition() && "expected enum definition");
15385 auto R = FlagBitsCache.insert(std::make_pair(ED, llvm::APInt()));
15386 llvm::APInt &FlagBits = R.first->second;
15389 for (auto *E : ED->enumerators()) {
15390 const auto &EVal = E->getInitVal();
15391 // Only single-bit enumerators introduce new flag values.
15392 if (EVal.isPowerOf2())
15393 FlagBits = FlagBits.zextOrSelf(EVal.getBitWidth()) | EVal;
15397 // A value is in a flag enum if either its bits are a subset of the enum's
15398 // flag bits (the first condition) or we are allowing masks and the same is
15399 // true of its complement (the second condition). When masks are allowed, we
15400 // allow the common idiom of ~(enum1 | enum2) to be a valid enum value.
15402 // While it's true that any value could be used as a mask, the assumption is
15403 // that a mask will have all of the insignificant bits set. Anything else is
15404 // likely a logic error.
15405 llvm::APInt FlagMask = ~FlagBits.zextOrTrunc(Val.getBitWidth());
15406 return !(FlagMask & Val) || (AllowMask && !(FlagMask & ~Val));
15409 void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceRange BraceRange,
15411 ArrayRef<Decl *> Elements,
15412 Scope *S, AttributeList *Attr) {
15413 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX);
15414 QualType EnumType = Context.getTypeDeclType(Enum);
15417 ProcessDeclAttributeList(S, Enum, Attr);
15419 if (Enum->isDependentType()) {
15420 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15421 EnumConstantDecl *ECD =
15422 cast_or_null<EnumConstantDecl>(Elements[i]);
15423 if (!ECD) continue;
15425 ECD->setType(EnumType);
15428 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0);
15432 // TODO: If the result value doesn't fit in an int, it must be a long or long
15433 // long value. ISO C does not support this, but GCC does as an extension,
15435 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
15436 unsigned CharWidth = Context.getTargetInfo().getCharWidth();
15437 unsigned ShortWidth = Context.getTargetInfo().getShortWidth();
15439 // Verify that all the values are okay, compute the size of the values, and
15440 // reverse the list.
15441 unsigned NumNegativeBits = 0;
15442 unsigned NumPositiveBits = 0;
15444 // Keep track of whether all elements have type int.
15445 bool AllElementsInt = true;
15447 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15448 EnumConstantDecl *ECD =
15449 cast_or_null<EnumConstantDecl>(Elements[i]);
15450 if (!ECD) continue; // Already issued a diagnostic.
15452 const llvm::APSInt &InitVal = ECD->getInitVal();
15454 // Keep track of the size of positive and negative values.
15455 if (InitVal.isUnsigned() || InitVal.isNonNegative())
15456 NumPositiveBits = std::max(NumPositiveBits,
15457 (unsigned)InitVal.getActiveBits());
15459 NumNegativeBits = std::max(NumNegativeBits,
15460 (unsigned)InitVal.getMinSignedBits());
15462 // Keep track of whether every enum element has type int (very commmon).
15463 if (AllElementsInt)
15464 AllElementsInt = ECD->getType() == Context.IntTy;
15467 // Figure out the type that should be used for this enum.
15469 unsigned BestWidth;
15471 // C++0x N3000 [conv.prom]p3:
15472 // An rvalue of an unscoped enumeration type whose underlying
15473 // type is not fixed can be converted to an rvalue of the first
15474 // of the following types that can represent all the values of
15475 // the enumeration: int, unsigned int, long int, unsigned long
15476 // int, long long int, or unsigned long long int.
15478 // An identifier declared as an enumeration constant has type int.
15479 // The C99 rule is modified by a gcc extension
15480 QualType BestPromotionType;
15482 bool Packed = Enum->hasAttr<PackedAttr>();
15483 // -fshort-enums is the equivalent to specifying the packed attribute on all
15484 // enum definitions.
15485 if (LangOpts.ShortEnums)
15488 if (Enum->isFixed()) {
15489 BestType = Enum->getIntegerType();
15490 if (BestType->isPromotableIntegerType())
15491 BestPromotionType = Context.getPromotedIntegerType(BestType);
15493 BestPromotionType = BestType;
15495 BestWidth = Context.getIntWidth(BestType);
15497 else if (NumNegativeBits) {
15498 // If there is a negative value, figure out the smallest integer type (of
15499 // int/long/longlong) that fits.
15500 // If it's packed, check also if it fits a char or a short.
15501 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
15502 BestType = Context.SignedCharTy;
15503 BestWidth = CharWidth;
15504 } else if (Packed && NumNegativeBits <= ShortWidth &&
15505 NumPositiveBits < ShortWidth) {
15506 BestType = Context.ShortTy;
15507 BestWidth = ShortWidth;
15508 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
15509 BestType = Context.IntTy;
15510 BestWidth = IntWidth;
15512 BestWidth = Context.getTargetInfo().getLongWidth();
15514 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) {
15515 BestType = Context.LongTy;
15517 BestWidth = Context.getTargetInfo().getLongLongWidth();
15519 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth)
15520 Diag(Enum->getLocation(), diag::ext_enum_too_large);
15521 BestType = Context.LongLongTy;
15524 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType);
15526 // If there is no negative value, figure out the smallest type that fits
15527 // all of the enumerator values.
15528 // If it's packed, check also if it fits a char or a short.
15529 if (Packed && NumPositiveBits <= CharWidth) {
15530 BestType = Context.UnsignedCharTy;
15531 BestPromotionType = Context.IntTy;
15532 BestWidth = CharWidth;
15533 } else if (Packed && NumPositiveBits <= ShortWidth) {
15534 BestType = Context.UnsignedShortTy;
15535 BestPromotionType = Context.IntTy;
15536 BestWidth = ShortWidth;
15537 } else if (NumPositiveBits <= IntWidth) {
15538 BestType = Context.UnsignedIntTy;
15539 BestWidth = IntWidth;
15541 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
15542 ? Context.UnsignedIntTy : Context.IntTy;
15543 } else if (NumPositiveBits <=
15544 (BestWidth = Context.getTargetInfo().getLongWidth())) {
15545 BestType = Context.UnsignedLongTy;
15547 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
15548 ? Context.UnsignedLongTy : Context.LongTy;
15550 BestWidth = Context.getTargetInfo().getLongLongWidth();
15551 assert(NumPositiveBits <= BestWidth &&
15552 "How could an initializer get larger than ULL?");
15553 BestType = Context.UnsignedLongLongTy;
15555 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
15556 ? Context.UnsignedLongLongTy : Context.LongLongTy;
15560 // Loop over all of the enumerator constants, changing their types to match
15561 // the type of the enum if needed.
15562 for (auto *D : Elements) {
15563 auto *ECD = cast_or_null<EnumConstantDecl>(D);
15564 if (!ECD) continue; // Already issued a diagnostic.
15566 // Standard C says the enumerators have int type, but we allow, as an
15567 // extension, the enumerators to be larger than int size. If each
15568 // enumerator value fits in an int, type it as an int, otherwise type it the
15569 // same as the enumerator decl itself. This means that in "enum { X = 1U }"
15570 // that X has type 'int', not 'unsigned'.
15572 // Determine whether the value fits into an int.
15573 llvm::APSInt InitVal = ECD->getInitVal();
15575 // If it fits into an integer type, force it. Otherwise force it to match
15576 // the enum decl type.
15580 if (!getLangOpts().CPlusPlus &&
15581 !Enum->isFixed() &&
15582 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) {
15583 NewTy = Context.IntTy;
15584 NewWidth = IntWidth;
15586 } else if (ECD->getType() == BestType) {
15587 // Already the right type!
15588 if (getLangOpts().CPlusPlus)
15589 // C++ [dcl.enum]p4: Following the closing brace of an
15590 // enum-specifier, each enumerator has the type of its
15592 ECD->setType(EnumType);
15596 NewWidth = BestWidth;
15597 NewSign = BestType->isSignedIntegerOrEnumerationType();
15600 // Adjust the APSInt value.
15601 InitVal = InitVal.extOrTrunc(NewWidth);
15602 InitVal.setIsSigned(NewSign);
15603 ECD->setInitVal(InitVal);
15605 // Adjust the Expr initializer and type.
15606 if (ECD->getInitExpr() &&
15607 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType()))
15608 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy,
15610 ECD->getInitExpr(),
15611 /*base paths*/ nullptr,
15613 if (getLangOpts().CPlusPlus)
15614 // C++ [dcl.enum]p4: Following the closing brace of an
15615 // enum-specifier, each enumerator has the type of its
15617 ECD->setType(EnumType);
15619 ECD->setType(NewTy);
15622 Enum->completeDefinition(BestType, BestPromotionType,
15623 NumPositiveBits, NumNegativeBits);
15625 CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType);
15627 if (Enum->isClosedFlag()) {
15628 for (Decl *D : Elements) {
15629 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(D);
15630 if (!ECD) continue; // Already issued a diagnostic.
15632 llvm::APSInt InitVal = ECD->getInitVal();
15633 if (InitVal != 0 && !InitVal.isPowerOf2() &&
15634 !IsValueInFlagEnum(Enum, InitVal, true))
15635 Diag(ECD->getLocation(), diag::warn_flag_enum_constant_out_of_range)
15640 // Now that the enum type is defined, ensure it's not been underaligned.
15641 if (Enum->hasAttrs())
15642 CheckAlignasUnderalignment(Enum);
15645 Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr,
15646 SourceLocation StartLoc,
15647 SourceLocation EndLoc) {
15648 StringLiteral *AsmString = cast<StringLiteral>(expr);
15650 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext,
15651 AsmString, StartLoc,
15653 CurContext->addDecl(New);
15657 static void checkModuleImportContext(Sema &S, Module *M,
15658 SourceLocation ImportLoc, DeclContext *DC,
15659 bool FromInclude = false) {
15660 SourceLocation ExternCLoc;
15662 if (auto *LSD = dyn_cast<LinkageSpecDecl>(DC)) {
15663 switch (LSD->getLanguage()) {
15664 case LinkageSpecDecl::lang_c:
15665 if (ExternCLoc.isInvalid())
15666 ExternCLoc = LSD->getLocStart();
15668 case LinkageSpecDecl::lang_cxx:
15671 DC = LSD->getParent();
15674 while (isa<LinkageSpecDecl>(DC))
15675 DC = DC->getParent();
15677 if (!isa<TranslationUnitDecl>(DC)) {
15678 S.Diag(ImportLoc, (FromInclude && S.isModuleVisible(M))
15679 ? diag::ext_module_import_not_at_top_level_noop
15680 : diag::err_module_import_not_at_top_level_fatal)
15681 << M->getFullModuleName() << DC;
15682 S.Diag(cast<Decl>(DC)->getLocStart(),
15683 diag::note_module_import_not_at_top_level) << DC;
15684 } else if (!M->IsExternC && ExternCLoc.isValid()) {
15685 S.Diag(ImportLoc, diag::ext_module_import_in_extern_c)
15686 << M->getFullModuleName();
15687 S.Diag(ExternCLoc, diag::note_extern_c_begins_here);
15691 Sema::DeclGroupPtrTy Sema::ActOnModuleDecl(SourceLocation StartLoc,
15692 SourceLocation ModuleLoc,
15693 ModuleDeclKind MDK,
15694 ModuleIdPath Path) {
15695 // A module implementation unit requires that we are not compiling a module
15696 // of any kind. A module interface unit requires that we are not compiling a
15698 switch (getLangOpts().getCompilingModule()) {
15699 case LangOptions::CMK_None:
15700 // It's OK to compile a module interface as a normal translation unit.
15703 case LangOptions::CMK_ModuleInterface:
15704 if (MDK != ModuleDeclKind::Implementation)
15707 // We were asked to compile a module interface unit but this is a module
15708 // implementation unit. That indicates the 'export' is missing.
15709 Diag(ModuleLoc, diag::err_module_interface_implementation_mismatch)
15710 << FixItHint::CreateInsertion(ModuleLoc, "export ");
15713 case LangOptions::CMK_ModuleMap:
15714 Diag(ModuleLoc, diag::err_module_decl_in_module_map_module);
15718 // FIXME: Create a ModuleDecl and return it.
15720 // FIXME: Most of this work should be done by the preprocessor rather than
15721 // here, in order to support macro import.
15723 // Flatten the dots in a module name. Unlike Clang's hierarchical module map
15724 // modules, the dots here are just another character that can appear in a
15726 std::string ModuleName;
15727 for (auto &Piece : Path) {
15728 if (!ModuleName.empty())
15730 ModuleName += Piece.first->getName();
15733 // If a module name was explicitly specified on the command line, it must be
15735 if (!getLangOpts().CurrentModule.empty() &&
15736 getLangOpts().CurrentModule != ModuleName) {
15737 Diag(Path.front().second, diag::err_current_module_name_mismatch)
15738 << SourceRange(Path.front().second, Path.back().second)
15739 << getLangOpts().CurrentModule;
15742 const_cast<LangOptions&>(getLangOpts()).CurrentModule = ModuleName;
15744 auto &Map = PP.getHeaderSearchInfo().getModuleMap();
15747 case ModuleDeclKind::Module: {
15748 // FIXME: Check we're not in a submodule.
15750 // We can't have parsed or imported a definition of this module or parsed a
15751 // module map defining it already.
15752 if (auto *M = Map.findModule(ModuleName)) {
15753 Diag(Path[0].second, diag::err_module_redefinition) << ModuleName;
15754 if (M->DefinitionLoc.isValid())
15755 Diag(M->DefinitionLoc, diag::note_prev_module_definition);
15756 else if (const auto *FE = M->getASTFile())
15757 Diag(M->DefinitionLoc, diag::note_prev_module_definition_from_ast_file)
15762 // Create a Module for the module that we're defining.
15763 Module *Mod = Map.createModuleForInterfaceUnit(ModuleLoc, ModuleName);
15764 assert(Mod && "module creation should not fail");
15766 // Enter the semantic scope of the module.
15767 ActOnModuleBegin(ModuleLoc, Mod);
15771 case ModuleDeclKind::Partition:
15772 // FIXME: Check we are in a submodule of the named module.
15775 case ModuleDeclKind::Implementation:
15776 std::pair<IdentifierInfo *, SourceLocation> ModuleNameLoc(
15777 PP.getIdentifierInfo(ModuleName), Path[0].second);
15779 DeclResult Import = ActOnModuleImport(ModuleLoc, ModuleLoc, ModuleNameLoc);
15780 if (Import.isInvalid())
15782 return ConvertDeclToDeclGroup(Import.get());
15785 llvm_unreachable("unexpected module decl kind");
15788 DeclResult Sema::ActOnModuleImport(SourceLocation StartLoc,
15789 SourceLocation ImportLoc,
15790 ModuleIdPath Path) {
15792 getModuleLoader().loadModule(ImportLoc, Path, Module::AllVisible,
15793 /*IsIncludeDirective=*/false);
15797 VisibleModules.setVisible(Mod, ImportLoc);
15799 checkModuleImportContext(*this, Mod, ImportLoc, CurContext);
15801 // FIXME: we should support importing a submodule within a different submodule
15802 // of the same top-level module. Until we do, make it an error rather than
15803 // silently ignoring the import.
15804 // Import-from-implementation is valid in the Modules TS. FIXME: Should we
15805 // warn on a redundant import of the current module?
15806 if (Mod->getTopLevelModuleName() == getLangOpts().CurrentModule &&
15807 (getLangOpts().isCompilingModule() || !getLangOpts().ModulesTS))
15808 Diag(ImportLoc, getLangOpts().isCompilingModule()
15809 ? diag::err_module_self_import
15810 : diag::err_module_import_in_implementation)
15811 << Mod->getFullModuleName() << getLangOpts().CurrentModule;
15813 SmallVector<SourceLocation, 2> IdentifierLocs;
15814 Module *ModCheck = Mod;
15815 for (unsigned I = 0, N = Path.size(); I != N; ++I) {
15816 // If we've run out of module parents, just drop the remaining identifiers.
15817 // We need the length to be consistent.
15820 ModCheck = ModCheck->Parent;
15822 IdentifierLocs.push_back(Path[I].second);
15825 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15826 ImportDecl *Import = ImportDecl::Create(Context, TU, StartLoc,
15827 Mod, IdentifierLocs);
15828 if (!ModuleScopes.empty())
15829 Context.addModuleInitializer(ModuleScopes.back().Module, Import);
15830 TU->addDecl(Import);
15834 void Sema::ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
15835 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext, true);
15836 BuildModuleInclude(DirectiveLoc, Mod);
15839 void Sema::BuildModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
15840 // Determine whether we're in the #include buffer for a module. The #includes
15841 // in that buffer do not qualify as module imports; they're just an
15842 // implementation detail of us building the module.
15844 // FIXME: Should we even get ActOnModuleInclude calls for those?
15845 bool IsInModuleIncludes =
15846 TUKind == TU_Module &&
15847 getSourceManager().isWrittenInMainFile(DirectiveLoc);
15849 bool ShouldAddImport = !IsInModuleIncludes;
15851 // If this module import was due to an inclusion directive, create an
15852 // implicit import declaration to capture it in the AST.
15853 if (ShouldAddImport) {
15854 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15855 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
15858 if (!ModuleScopes.empty())
15859 Context.addModuleInitializer(ModuleScopes.back().Module, ImportD);
15860 TU->addDecl(ImportD);
15861 Consumer.HandleImplicitImportDecl(ImportD);
15864 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, DirectiveLoc);
15865 VisibleModules.setVisible(Mod, DirectiveLoc);
15868 void Sema::ActOnModuleBegin(SourceLocation DirectiveLoc, Module *Mod) {
15869 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext, true);
15871 ModuleScopes.push_back({});
15872 ModuleScopes.back().Module = Mod;
15873 if (getLangOpts().ModulesLocalVisibility)
15874 ModuleScopes.back().OuterVisibleModules = std::move(VisibleModules);
15876 VisibleModules.setVisible(Mod, DirectiveLoc);
15879 void Sema::ActOnModuleEnd(SourceLocation EofLoc, Module *Mod) {
15880 if (getLangOpts().ModulesLocalVisibility) {
15881 VisibleModules = std::move(ModuleScopes.back().OuterVisibleModules);
15882 // Leaving a module hides namespace names, so our visible namespace cache
15883 // is now out of date.
15884 VisibleNamespaceCache.clear();
15887 assert(!ModuleScopes.empty() && ModuleScopes.back().Module == Mod &&
15888 "left the wrong module scope");
15889 ModuleScopes.pop_back();
15891 // We got to the end of processing a #include of a local module. Create an
15892 // ImportDecl as we would for an imported module.
15893 FileID File = getSourceManager().getFileID(EofLoc);
15894 assert(File != getSourceManager().getMainFileID() &&
15895 "end of submodule in main source file");
15896 SourceLocation DirectiveLoc = getSourceManager().getIncludeLoc(File);
15897 BuildModuleInclude(DirectiveLoc, Mod);
15900 void Sema::createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
15902 // Bail if we're not allowed to implicitly import a module here.
15903 if (isSFINAEContext() || !getLangOpts().ModulesErrorRecovery)
15906 // Create the implicit import declaration.
15907 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15908 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
15910 TU->addDecl(ImportD);
15911 Consumer.HandleImplicitImportDecl(ImportD);
15913 // Make the module visible.
15914 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, Loc);
15915 VisibleModules.setVisible(Mod, Loc);
15918 /// We have parsed the start of an export declaration, including the '{'
15920 Decl *Sema::ActOnStartExportDecl(Scope *S, SourceLocation ExportLoc,
15921 SourceLocation LBraceLoc) {
15922 ExportDecl *D = ExportDecl::Create(Context, CurContext, ExportLoc);
15924 // C++ Modules TS draft:
15925 // An export-declaration shall appear in the purview of a module other than
15926 // the global module.
15927 if (ModuleScopes.empty() || !ModuleScopes.back().Module ||
15928 ModuleScopes.back().Module->Kind != Module::ModuleInterfaceUnit)
15929 Diag(ExportLoc, diag::err_export_not_in_module_interface);
15931 // An export-declaration [...] shall not contain more than one
15934 // The intent here is that an export-declaration cannot appear within another
15935 // export-declaration.
15936 if (D->isExported())
15937 Diag(ExportLoc, diag::err_export_within_export);
15939 CurContext->addDecl(D);
15940 PushDeclContext(S, D);
15944 /// Complete the definition of an export declaration.
15945 Decl *Sema::ActOnFinishExportDecl(Scope *S, Decl *D, SourceLocation RBraceLoc) {
15946 auto *ED = cast<ExportDecl>(D);
15947 if (RBraceLoc.isValid())
15948 ED->setRBraceLoc(RBraceLoc);
15950 // FIXME: Diagnose export of internal-linkage declaration (including
15951 // anonymous namespace).
15957 void Sema::ActOnPragmaRedefineExtname(IdentifierInfo* Name,
15958 IdentifierInfo* AliasName,
15959 SourceLocation PragmaLoc,
15960 SourceLocation NameLoc,
15961 SourceLocation AliasNameLoc) {
15962 NamedDecl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc,
15963 LookupOrdinaryName);
15964 AsmLabelAttr *Attr =
15965 AsmLabelAttr::CreateImplicit(Context, AliasName->getName(), AliasNameLoc);
15967 // If a declaration that:
15968 // 1) declares a function or a variable
15969 // 2) has external linkage
15970 // already exists, add a label attribute to it.
15971 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
15972 if (isDeclExternC(PrevDecl))
15973 PrevDecl->addAttr(Attr);
15975 Diag(PrevDecl->getLocation(), diag::warn_redefine_extname_not_applied)
15976 << /*Variable*/(isa<FunctionDecl>(PrevDecl) ? 0 : 1) << PrevDecl;
15977 // Otherwise, add a label atttibute to ExtnameUndeclaredIdentifiers.
15979 (void)ExtnameUndeclaredIdentifiers.insert(std::make_pair(Name, Attr));
15982 void Sema::ActOnPragmaWeakID(IdentifierInfo* Name,
15983 SourceLocation PragmaLoc,
15984 SourceLocation NameLoc) {
15985 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName);
15988 PrevDecl->addAttr(WeakAttr::CreateImplicit(Context, PragmaLoc));
15990 (void)WeakUndeclaredIdentifiers.insert(
15991 std::pair<IdentifierInfo*,WeakInfo>
15992 (Name, WeakInfo((IdentifierInfo*)nullptr, NameLoc)));
15996 void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name,
15997 IdentifierInfo* AliasName,
15998 SourceLocation PragmaLoc,
15999 SourceLocation NameLoc,
16000 SourceLocation AliasNameLoc) {
16001 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc,
16002 LookupOrdinaryName);
16003 WeakInfo W = WeakInfo(Name, NameLoc);
16005 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
16006 if (!PrevDecl->hasAttr<AliasAttr>())
16007 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl))
16008 DeclApplyPragmaWeak(TUScope, ND, W);
16010 (void)WeakUndeclaredIdentifiers.insert(
16011 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W));
16015 Decl *Sema::getObjCDeclContext() const {
16016 return (dyn_cast_or_null<ObjCContainerDecl>(CurContext));