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 AllowClassTemplates(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 = AllowClassTemplates && isa<ClassTemplateDecl>(ND);
80 return (IsType || AllowedTemplate) &&
81 (AllowInvalidDecl || !ND->isInvalidDecl());
83 return !WantClassName && candidate.isKeyword();
87 bool AllowInvalidDecl;
89 bool AllowClassTemplates;
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 IdentifierInfo **CorrectedII) {
256 // Determine where we will perform name lookup.
257 DeclContext *LookupCtx = nullptr;
259 QualType ObjectType = ObjectTypePtr.get();
260 if (ObjectType->isRecordType())
261 LookupCtx = computeDeclContext(ObjectType);
262 } else if (SS && SS->isNotEmpty()) {
263 LookupCtx = computeDeclContext(*SS, false);
266 if (isDependentScopeSpecifier(*SS)) {
268 // A qualified-id that refers to a type and in which the
269 // nested-name-specifier depends on a template-parameter (14.6.2)
270 // shall be prefixed by the keyword typename to indicate that the
271 // qualified-id denotes a type, forming an
272 // elaborated-type-specifier (7.1.5.3).
274 // We therefore do not perform any name lookup if the result would
275 // refer to a member of an unknown specialization.
276 if (!isClassName && !IsCtorOrDtorName)
279 // We know from the grammar that this name refers to a type,
280 // so build a dependent node to describe the type.
281 if (WantNontrivialTypeSourceInfo)
282 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get();
284 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context);
285 QualType T = CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc,
287 return ParsedType::make(T);
293 if (!LookupCtx->isDependentContext() &&
294 RequireCompleteDeclContext(*SS, LookupCtx))
298 // FIXME: LookupNestedNameSpecifierName isn't the right kind of
299 // lookup for class-names.
300 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName :
302 LookupResult Result(*this, &II, NameLoc, Kind);
304 // Perform "qualified" name lookup into the declaration context we
305 // computed, which is either the type of the base of a member access
306 // expression or the declaration context associated with a prior
307 // nested-name-specifier.
308 LookupQualifiedName(Result, LookupCtx);
310 if (ObjectTypePtr && Result.empty()) {
311 // C++ [basic.lookup.classref]p3:
312 // If the unqualified-id is ~type-name, the type-name is looked up
313 // in the context of the entire postfix-expression. If the type T of
314 // the object expression is of a class type C, the type-name is also
315 // looked up in the scope of class C. At least one of the lookups shall
316 // find a name that refers to (possibly cv-qualified) T.
317 LookupName(Result, S);
320 // Perform unqualified name lookup.
321 LookupName(Result, S);
323 // For unqualified lookup in a class template in MSVC mode, look into
324 // dependent base classes where the primary class template is known.
325 if (Result.empty() && getLangOpts().MSVCCompat && (!SS || SS->isEmpty())) {
326 if (ParsedType TypeInBase =
327 recoverFromTypeInKnownDependentBase(*this, II, NameLoc))
332 NamedDecl *IIDecl = nullptr;
333 switch (Result.getResultKind()) {
334 case LookupResult::NotFound:
335 case LookupResult::NotFoundInCurrentInstantiation:
337 TypoCorrection Correction = CorrectTypo(
338 Result.getLookupNameInfo(), Kind, S, SS,
339 llvm::make_unique<TypeNameValidatorCCC>(true, isClassName),
341 IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo();
343 bool MemberOfUnknownSpecialization;
344 UnqualifiedId TemplateName;
345 TemplateName.setIdentifier(NewII, NameLoc);
346 NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier();
347 CXXScopeSpec NewSS, *NewSSPtr = SS;
349 NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
352 if (Correction && (NNS || NewII != &II) &&
353 // Ignore a correction to a template type as the to-be-corrected
354 // identifier is not a template (typo correction for template names
355 // is handled elsewhere).
356 !(getLangOpts().CPlusPlus && NewSSPtr &&
357 isTemplateName(S, *NewSSPtr, false, TemplateName, nullptr, false,
358 Template, MemberOfUnknownSpecialization))) {
359 ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr,
360 isClassName, HasTrailingDot, ObjectTypePtr,
362 WantNontrivialTypeSourceInfo);
364 diagnoseTypo(Correction,
365 PDiag(diag::err_unknown_type_or_class_name_suggest)
366 << Result.getLookupName() << isClassName);
368 SS->MakeTrivial(Context, NNS, SourceRange(NameLoc));
369 *CorrectedII = NewII;
374 // If typo correction failed or was not performed, fall through
375 case LookupResult::FoundOverloaded:
376 case LookupResult::FoundUnresolvedValue:
377 Result.suppressDiagnostics();
380 case LookupResult::Ambiguous:
381 // Recover from type-hiding ambiguities by hiding the type. We'll
382 // do the lookup again when looking for an object, and we can
383 // diagnose the error then. If we don't do this, then the error
384 // about hiding the type will be immediately followed by an error
385 // that only makes sense if the identifier was treated like a type.
386 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) {
387 Result.suppressDiagnostics();
391 // Look to see if we have a type anywhere in the list of results.
392 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end();
393 Res != ResEnd; ++Res) {
394 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) {
396 (*Res)->getLocation().getRawEncoding() <
397 IIDecl->getLocation().getRawEncoding())
403 // None of the entities we found is a type, so there is no way
404 // to even assume that the result is a type. In this case, don't
405 // complain about the ambiguity. The parser will either try to
406 // perform this lookup again (e.g., as an object name), which
407 // will produce the ambiguity, or will complain that it expected
409 Result.suppressDiagnostics();
413 // We found a type within the ambiguous lookup; diagnose the
414 // ambiguity and then return that type. This might be the right
415 // answer, or it might not be, but it suppresses any attempt to
416 // perform the name lookup again.
419 case LookupResult::Found:
420 IIDecl = Result.getFoundDecl();
424 assert(IIDecl && "Didn't find decl");
427 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) {
428 DiagnoseUseOfDecl(IIDecl, NameLoc);
430 T = Context.getTypeDeclType(TD);
431 MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
433 // NOTE: avoid constructing an ElaboratedType(Loc) if this is a
434 // constructor or destructor name (in such a case, the scope specifier
435 // will be attached to the enclosing Expr or Decl node).
436 if (SS && SS->isNotEmpty() && !IsCtorOrDtorName) {
437 if (WantNontrivialTypeSourceInfo) {
438 // Construct a type with type-source information.
439 TypeLocBuilder Builder;
440 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
442 T = getElaboratedType(ETK_None, *SS, T);
443 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
444 ElabTL.setElaboratedKeywordLoc(SourceLocation());
445 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context));
446 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
448 T = getElaboratedType(ETK_None, *SS, T);
451 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) {
452 (void)DiagnoseUseOfDecl(IDecl, NameLoc);
454 T = Context.getObjCInterfaceType(IDecl);
458 // If it's not plausibly a type, suppress diagnostics.
459 Result.suppressDiagnostics();
462 return ParsedType::make(T);
465 // Builds a fake NNS for the given decl context.
466 static NestedNameSpecifier *
467 synthesizeCurrentNestedNameSpecifier(ASTContext &Context, DeclContext *DC) {
468 for (;; DC = DC->getLookupParent()) {
469 DC = DC->getPrimaryContext();
470 auto *ND = dyn_cast<NamespaceDecl>(DC);
471 if (ND && !ND->isInline() && !ND->isAnonymousNamespace())
472 return NestedNameSpecifier::Create(Context, nullptr, ND);
473 else if (auto *RD = dyn_cast<CXXRecordDecl>(DC))
474 return NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
475 RD->getTypeForDecl());
476 else if (isa<TranslationUnitDecl>(DC))
477 return NestedNameSpecifier::GlobalSpecifier(Context);
479 llvm_unreachable("something isn't in TU scope?");
482 /// Find the parent class with dependent bases of the innermost enclosing method
483 /// context. Do not look for enclosing CXXRecordDecls directly, or we will end
484 /// up allowing unqualified dependent type names at class-level, which MSVC
485 /// correctly rejects.
486 static const CXXRecordDecl *
487 findRecordWithDependentBasesOfEnclosingMethod(const DeclContext *DC) {
488 for (; DC && DC->isDependentContext(); DC = DC->getLookupParent()) {
489 DC = DC->getPrimaryContext();
490 if (const auto *MD = dyn_cast<CXXMethodDecl>(DC))
491 if (MD->getParent()->hasAnyDependentBases())
492 return MD->getParent();
497 ParsedType Sema::ActOnMSVCUnknownTypeName(const IdentifierInfo &II,
498 SourceLocation NameLoc,
499 bool IsTemplateTypeArg) {
500 assert(getLangOpts().MSVCCompat && "shouldn't be called in non-MSVC mode");
502 NestedNameSpecifier *NNS = nullptr;
503 if (IsTemplateTypeArg && getCurScope()->isTemplateParamScope()) {
504 // If we weren't able to parse a default template argument, delay lookup
505 // until instantiation time by making a non-dependent DependentTypeName. We
506 // pretend we saw a NestedNameSpecifier referring to the current scope, and
507 // lookup is retried.
508 // FIXME: This hurts our diagnostic quality, since we get errors like "no
509 // type named 'Foo' in 'current_namespace'" when the user didn't write any
511 NNS = synthesizeCurrentNestedNameSpecifier(Context, CurContext);
512 Diag(NameLoc, diag::ext_ms_delayed_template_argument) << &II;
513 } else if (const CXXRecordDecl *RD =
514 findRecordWithDependentBasesOfEnclosingMethod(CurContext)) {
515 // Build a DependentNameType that will perform lookup into RD at
516 // instantiation time.
517 NNS = NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
518 RD->getTypeForDecl());
520 // Diagnose that this identifier was undeclared, and retry the lookup during
521 // template instantiation.
522 Diag(NameLoc, diag::ext_undeclared_unqual_id_with_dependent_base) << &II
525 // This is not a situation that we should recover from.
529 QualType T = Context.getDependentNameType(ETK_None, NNS, &II);
531 // Build type location information. We synthesized the qualifier, so we have
532 // to build a fake NestedNameSpecifierLoc.
533 NestedNameSpecifierLocBuilder NNSLocBuilder;
534 NNSLocBuilder.MakeTrivial(Context, NNS, SourceRange(NameLoc));
535 NestedNameSpecifierLoc QualifierLoc = NNSLocBuilder.getWithLocInContext(Context);
537 TypeLocBuilder Builder;
538 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
539 DepTL.setNameLoc(NameLoc);
540 DepTL.setElaboratedKeywordLoc(SourceLocation());
541 DepTL.setQualifierLoc(QualifierLoc);
542 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
545 /// isTagName() - This method is called *for error recovery purposes only*
546 /// to determine if the specified name is a valid tag name ("struct foo"). If
547 /// so, this returns the TST for the tag corresponding to it (TST_enum,
548 /// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose
549 /// cases in C where the user forgot to specify the tag.
550 DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) {
551 // Do a tag name lookup in this scope.
552 LookupResult R(*this, &II, SourceLocation(), LookupTagName);
553 LookupName(R, S, false);
554 R.suppressDiagnostics();
555 if (R.getResultKind() == LookupResult::Found)
556 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) {
557 switch (TD->getTagKind()) {
558 case TTK_Struct: return DeclSpec::TST_struct;
559 case TTK_Interface: return DeclSpec::TST_interface;
560 case TTK_Union: return DeclSpec::TST_union;
561 case TTK_Class: return DeclSpec::TST_class;
562 case TTK_Enum: return DeclSpec::TST_enum;
566 return DeclSpec::TST_unspecified;
569 /// isMicrosoftMissingTypename - In Microsoft mode, within class scope,
570 /// if a CXXScopeSpec's type is equal to the type of one of the base classes
571 /// then downgrade the missing typename error to a warning.
572 /// This is needed for MSVC compatibility; Example:
574 /// template<class T> class A {
576 /// typedef int TYPE;
578 /// template<class T> class B : public A<T> {
580 /// A<T>::TYPE a; // no typename required because A<T> is a base class.
583 bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) {
584 if (CurContext->isRecord()) {
585 if (SS->getScopeRep()->getKind() == NestedNameSpecifier::Super)
588 const Type *Ty = SS->getScopeRep()->getAsType();
590 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext);
591 for (const auto &Base : RD->bases())
592 if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base.getType()))
594 return S->isFunctionPrototypeScope();
596 return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope();
599 void Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II,
600 SourceLocation IILoc,
603 ParsedType &SuggestedType,
604 bool AllowClassTemplates) {
605 // We don't have anything to suggest (yet).
606 SuggestedType = nullptr;
608 // There may have been a typo in the name of the type. Look up typo
609 // results, in case we have something that we can suggest.
610 if (TypoCorrection Corrected =
611 CorrectTypo(DeclarationNameInfo(II, IILoc), LookupOrdinaryName, S, SS,
612 llvm::make_unique<TypeNameValidatorCCC>(
613 false, false, AllowClassTemplates),
614 CTK_ErrorRecovery)) {
615 if (Corrected.isKeyword()) {
616 // We corrected to a keyword.
617 diagnoseTypo(Corrected, PDiag(diag::err_unknown_typename_suggest) << II);
618 II = Corrected.getCorrectionAsIdentifierInfo();
620 // We found a similarly-named type or interface; suggest that.
621 if (!SS || !SS->isSet()) {
622 diagnoseTypo(Corrected,
623 PDiag(diag::err_unknown_typename_suggest) << II);
624 } else if (DeclContext *DC = computeDeclContext(*SS, false)) {
625 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
626 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
627 II->getName().equals(CorrectedStr);
628 diagnoseTypo(Corrected,
629 PDiag(diag::err_unknown_nested_typename_suggest)
630 << II << DC << DroppedSpecifier << SS->getRange());
632 llvm_unreachable("could not have corrected a typo here");
636 if (Corrected.getCorrectionSpecifier())
637 tmpSS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
640 getTypeName(*Corrected.getCorrectionAsIdentifierInfo(), IILoc, S,
641 tmpSS.isSet() ? &tmpSS : SS, false, false, nullptr,
642 /*IsCtorOrDtorName=*/false,
643 /*NonTrivialTypeSourceInfo=*/true);
648 if (getLangOpts().CPlusPlus) {
649 // See if II is a class template that the user forgot to pass arguments to.
651 Name.setIdentifier(II, IILoc);
652 CXXScopeSpec EmptySS;
653 TemplateTy TemplateResult;
654 bool MemberOfUnknownSpecialization;
655 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false,
656 Name, nullptr, true, TemplateResult,
657 MemberOfUnknownSpecialization) == TNK_Type_template) {
658 TemplateName TplName = TemplateResult.get();
659 Diag(IILoc, diag::err_template_missing_args) << TplName;
660 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) {
661 Diag(TplDecl->getLocation(), diag::note_template_decl_here)
662 << TplDecl->getTemplateParameters()->getSourceRange();
668 // FIXME: Should we move the logic that tries to recover from a missing tag
669 // (struct, union, enum) from Parser::ParseImplicitInt here, instead?
671 if (!SS || (!SS->isSet() && !SS->isInvalid()))
672 Diag(IILoc, diag::err_unknown_typename) << II;
673 else if (DeclContext *DC = computeDeclContext(*SS, false))
674 Diag(IILoc, diag::err_typename_nested_not_found)
675 << II << DC << SS->getRange();
676 else if (isDependentScopeSpecifier(*SS)) {
677 unsigned DiagID = diag::err_typename_missing;
678 if (getLangOpts().MSVCCompat && isMicrosoftMissingTypename(SS, S))
679 DiagID = diag::ext_typename_missing;
681 Diag(SS->getRange().getBegin(), DiagID)
682 << SS->getScopeRep() << II->getName()
683 << SourceRange(SS->getRange().getBegin(), IILoc)
684 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename ");
685 SuggestedType = ActOnTypenameType(S, SourceLocation(),
686 *SS, *II, IILoc).get();
688 assert(SS && SS->isInvalid() &&
689 "Invalid scope specifier has already been diagnosed");
693 /// \brief Determine whether the given result set contains either a type name
695 static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) {
696 bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus &&
697 NextToken.is(tok::less);
699 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) {
700 if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I))
703 if (CheckTemplate && isa<TemplateDecl>(*I))
710 static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result,
711 Scope *S, CXXScopeSpec &SS,
712 IdentifierInfo *&Name,
713 SourceLocation NameLoc) {
714 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName);
715 SemaRef.LookupParsedName(R, S, &SS);
716 if (TagDecl *Tag = R.getAsSingle<TagDecl>()) {
717 StringRef FixItTagName;
718 switch (Tag->getTagKind()) {
720 FixItTagName = "class ";
724 FixItTagName = "enum ";
728 FixItTagName = "struct ";
732 FixItTagName = "__interface ";
736 FixItTagName = "union ";
740 StringRef TagName = FixItTagName.drop_back();
741 SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag)
742 << Name << TagName << SemaRef.getLangOpts().CPlusPlus
743 << FixItHint::CreateInsertion(NameLoc, FixItTagName);
745 for (LookupResult::iterator I = Result.begin(), IEnd = Result.end();
747 SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type)
750 // Replace lookup results with just the tag decl.
751 Result.clear(Sema::LookupTagName);
752 SemaRef.LookupParsedName(Result, S, &SS);
759 /// Build a ParsedType for a simple-type-specifier with a nested-name-specifier.
760 static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS,
761 QualType T, SourceLocation NameLoc) {
762 ASTContext &Context = S.Context;
764 TypeLocBuilder Builder;
765 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
767 T = S.getElaboratedType(ETK_None, SS, T);
768 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
769 ElabTL.setElaboratedKeywordLoc(SourceLocation());
770 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
771 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
774 Sema::NameClassification
775 Sema::ClassifyName(Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name,
776 SourceLocation NameLoc, const Token &NextToken,
777 bool IsAddressOfOperand,
778 std::unique_ptr<CorrectionCandidateCallback> CCC) {
779 DeclarationNameInfo NameInfo(Name, NameLoc);
780 ObjCMethodDecl *CurMethod = getCurMethodDecl();
782 if (NextToken.is(tok::coloncolon)) {
783 NestedNameSpecInfo IdInfo(Name, NameLoc, NextToken.getLocation());
784 BuildCXXNestedNameSpecifier(S, IdInfo, false, SS, nullptr, false);
787 LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName);
788 LookupParsedName(Result, S, &SS, !CurMethod);
790 // For unqualified lookup in a class template in MSVC mode, look into
791 // dependent base classes where the primary class template is known.
792 if (Result.empty() && SS.isEmpty() && getLangOpts().MSVCCompat) {
793 if (ParsedType TypeInBase =
794 recoverFromTypeInKnownDependentBase(*this, *Name, NameLoc))
798 // Perform lookup for Objective-C instance variables (including automatically
799 // synthesized instance variables), if we're in an Objective-C method.
800 // FIXME: This lookup really, really needs to be folded in to the normal
801 // unqualified lookup mechanism.
802 if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) {
803 ExprResult E = LookupInObjCMethod(Result, S, Name, true);
804 if (E.get() || E.isInvalid())
808 bool SecondTry = false;
809 bool IsFilteredTemplateName = false;
812 switch (Result.getResultKind()) {
813 case LookupResult::NotFound:
814 // If an unqualified-id is followed by a '(', then we have a function
816 if (!SS.isSet() && NextToken.is(tok::l_paren)) {
817 // In C++, this is an ADL-only call.
819 if (getLangOpts().CPlusPlus)
820 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true);
823 // If the expression that precedes the parenthesized argument list in a
824 // function call consists solely of an identifier, and if no
825 // declaration is visible for this identifier, the identifier is
826 // implicitly declared exactly as if, in the innermost block containing
827 // the function call, the declaration
829 // extern int identifier ();
833 // We also allow this in C99 as an extension.
834 if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) {
836 Result.resolveKind();
837 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false);
841 // In C, we first see whether there is a tag type by the same name, in
842 // which case it's likely that the user just forgot to write "enum",
843 // "struct", or "union".
844 if (!getLangOpts().CPlusPlus && !SecondTry &&
845 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
849 // Perform typo correction to determine if there is another name that is
850 // close to this name.
851 if (!SecondTry && CCC) {
853 if (TypoCorrection Corrected = CorrectTypo(Result.getLookupNameInfo(),
854 Result.getLookupKind(), S,
856 CTK_ErrorRecovery)) {
857 unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest;
858 unsigned QualifiedDiag = diag::err_no_member_suggest;
860 NamedDecl *FirstDecl = Corrected.getFoundDecl();
861 NamedDecl *UnderlyingFirstDecl = Corrected.getCorrectionDecl();
862 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
863 UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) {
864 UnqualifiedDiag = diag::err_no_template_suggest;
865 QualifiedDiag = diag::err_no_member_template_suggest;
866 } else if (UnderlyingFirstDecl &&
867 (isa<TypeDecl>(UnderlyingFirstDecl) ||
868 isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) ||
869 isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) {
870 UnqualifiedDiag = diag::err_unknown_typename_suggest;
871 QualifiedDiag = diag::err_unknown_nested_typename_suggest;
875 diagnoseTypo(Corrected, PDiag(UnqualifiedDiag) << Name);
876 } else {// FIXME: is this even reachable? Test it.
877 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
878 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
879 Name->getName().equals(CorrectedStr);
880 diagnoseTypo(Corrected, PDiag(QualifiedDiag)
881 << Name << computeDeclContext(SS, false)
882 << DroppedSpecifier << SS.getRange());
885 // Update the name, so that the caller has the new name.
886 Name = Corrected.getCorrectionAsIdentifierInfo();
888 // Typo correction corrected to a keyword.
889 if (Corrected.isKeyword())
892 // Also update the LookupResult...
893 // FIXME: This should probably go away at some point
895 Result.setLookupName(Corrected.getCorrection());
897 Result.addDecl(FirstDecl);
899 // If we found an Objective-C instance variable, let
900 // LookupInObjCMethod build the appropriate expression to
901 // reference the ivar.
902 // FIXME: This is a gross hack.
903 if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) {
905 ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier()));
913 // We failed to correct; just fall through and let the parser deal with it.
914 Result.suppressDiagnostics();
915 return NameClassification::Unknown();
917 case LookupResult::NotFoundInCurrentInstantiation: {
918 // We performed name lookup into the current instantiation, and there were
919 // dependent bases, so we treat this result the same way as any other
920 // dependent nested-name-specifier.
923 // A name used in a template declaration or definition and that is
924 // dependent on a template-parameter is assumed not to name a type
925 // unless the applicable name lookup finds a type name or the name is
926 // qualified by the keyword typename.
928 // FIXME: If the next token is '<', we might want to ask the parser to
929 // perform some heroics to see if we actually have a
930 // template-argument-list, which would indicate a missing 'template'
932 return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(),
933 NameInfo, IsAddressOfOperand,
934 /*TemplateArgs=*/nullptr);
937 case LookupResult::Found:
938 case LookupResult::FoundOverloaded:
939 case LookupResult::FoundUnresolvedValue:
942 case LookupResult::Ambiguous:
943 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
944 hasAnyAcceptableTemplateNames(Result)) {
945 // C++ [temp.local]p3:
946 // A lookup that finds an injected-class-name (10.2) can result in an
947 // ambiguity in certain cases (for example, if it is found in more than
948 // one base class). If all of the injected-class-names that are found
949 // refer to specializations of the same class template, and if the name
950 // is followed by a template-argument-list, the reference refers to the
951 // class template itself and not a specialization thereof, and is not
954 // This filtering can make an ambiguous result into an unambiguous one,
955 // so try again after filtering out template names.
956 FilterAcceptableTemplateNames(Result);
957 if (!Result.isAmbiguous()) {
958 IsFilteredTemplateName = true;
963 // Diagnose the ambiguity and return an error.
964 return NameClassification::Error();
967 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
968 (IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) {
969 // C++ [temp.names]p3:
970 // After name lookup (3.4) finds that a name is a template-name or that
971 // an operator-function-id or a literal- operator-id refers to a set of
972 // overloaded functions any member of which is a function template if
973 // this is followed by a <, the < is always taken as the delimiter of a
974 // template-argument-list and never as the less-than operator.
975 if (!IsFilteredTemplateName)
976 FilterAcceptableTemplateNames(Result);
978 if (!Result.empty()) {
979 bool IsFunctionTemplate;
981 TemplateName Template;
982 if (Result.end() - Result.begin() > 1) {
983 IsFunctionTemplate = true;
984 Template = Context.getOverloadedTemplateName(Result.begin(),
988 = cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl());
989 IsFunctionTemplate = isa<FunctionTemplateDecl>(TD);
990 IsVarTemplate = isa<VarTemplateDecl>(TD);
992 if (SS.isSet() && !SS.isInvalid())
993 Template = Context.getQualifiedTemplateName(SS.getScopeRep(),
994 /*TemplateKeyword=*/false,
997 Template = TemplateName(TD);
1000 if (IsFunctionTemplate) {
1001 // Function templates always go through overload resolution, at which
1002 // point we'll perform the various checks (e.g., accessibility) we need
1003 // to based on which function we selected.
1004 Result.suppressDiagnostics();
1006 return NameClassification::FunctionTemplate(Template);
1009 return IsVarTemplate ? NameClassification::VarTemplate(Template)
1010 : NameClassification::TypeTemplate(Template);
1014 NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl();
1015 if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) {
1016 DiagnoseUseOfDecl(Type, NameLoc);
1017 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
1018 QualType T = Context.getTypeDeclType(Type);
1019 if (SS.isNotEmpty())
1020 return buildNestedType(*this, SS, T, NameLoc);
1021 return ParsedType::make(T);
1024 ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl);
1026 // FIXME: It's unfortunate that we don't have a Type node for handling this.
1027 if (ObjCCompatibleAliasDecl *Alias =
1028 dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl))
1029 Class = Alias->getClassInterface();
1033 DiagnoseUseOfDecl(Class, NameLoc);
1035 if (NextToken.is(tok::period)) {
1036 // Interface. <something> is parsed as a property reference expression.
1037 // Just return "unknown" as a fall-through for now.
1038 Result.suppressDiagnostics();
1039 return NameClassification::Unknown();
1042 QualType T = Context.getObjCInterfaceType(Class);
1043 return ParsedType::make(T);
1046 // We can have a type template here if we're classifying a template argument.
1047 if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl) &&
1048 !isa<VarTemplateDecl>(FirstDecl))
1049 return NameClassification::TypeTemplate(
1050 TemplateName(cast<TemplateDecl>(FirstDecl)));
1052 // Check for a tag type hidden by a non-type decl in a few cases where it
1053 // seems likely a type is wanted instead of the non-type that was found.
1054 bool NextIsOp = NextToken.isOneOf(tok::amp, tok::star);
1055 if ((NextToken.is(tok::identifier) ||
1057 FirstDecl->getUnderlyingDecl()->isFunctionOrFunctionTemplate())) &&
1058 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
1059 TypeDecl *Type = Result.getAsSingle<TypeDecl>();
1060 DiagnoseUseOfDecl(Type, NameLoc);
1061 QualType T = Context.getTypeDeclType(Type);
1062 if (SS.isNotEmpty())
1063 return buildNestedType(*this, SS, T, NameLoc);
1064 return ParsedType::make(T);
1067 if (FirstDecl->isCXXClassMember())
1068 return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result,
1071 bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren));
1072 return BuildDeclarationNameExpr(SS, Result, ADL);
1075 // Determines the context to return to after temporarily entering a
1076 // context. This depends in an unnecessarily complicated way on the
1077 // exact ordering of callbacks from the parser.
1078 DeclContext *Sema::getContainingDC(DeclContext *DC) {
1080 // Functions defined inline within classes aren't parsed until we've
1081 // finished parsing the top-level class, so the top-level class is
1082 // the context we'll need to return to.
1083 // A Lambda call operator whose parent is a class must not be treated
1084 // as an inline member function. A Lambda can be used legally
1085 // either as an in-class member initializer or a default argument. These
1086 // are parsed once the class has been marked complete and so the containing
1087 // context would be the nested class (when the lambda is defined in one);
1088 // If the class is not complete, then the lambda is being used in an
1089 // ill-formed fashion (such as to specify the width of a bit-field, or
1090 // in an array-bound) - in which case we still want to return the
1091 // lexically containing DC (which could be a nested class).
1092 if (isa<FunctionDecl>(DC) && !isLambdaCallOperator(DC)) {
1093 DC = DC->getLexicalParent();
1095 // A function not defined within a class will always return to its
1097 if (!isa<CXXRecordDecl>(DC))
1100 // A C++ inline method/friend is parsed *after* the topmost class
1101 // it was declared in is fully parsed ("complete"); the topmost
1102 // class is the context we need to return to.
1103 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent()))
1106 // Return the declaration context of the topmost class the inline method is
1111 return DC->getLexicalParent();
1114 void Sema::PushDeclContext(Scope *S, DeclContext *DC) {
1115 assert(getContainingDC(DC) == CurContext &&
1116 "The next DeclContext should be lexically contained in the current one.");
1121 void Sema::PopDeclContext() {
1122 assert(CurContext && "DeclContext imbalance!");
1124 CurContext = getContainingDC(CurContext);
1125 assert(CurContext && "Popped translation unit!");
1128 Sema::SkippedDefinitionContext Sema::ActOnTagStartSkippedDefinition(Scope *S,
1130 // Unlike PushDeclContext, the context to which we return is not necessarily
1131 // the containing DC of TD, because the new context will be some pre-existing
1132 // TagDecl definition instead of a fresh one.
1133 auto Result = static_cast<SkippedDefinitionContext>(CurContext);
1134 CurContext = cast<TagDecl>(D)->getDefinition();
1135 assert(CurContext && "skipping definition of undefined tag");
1136 // Start lookups from the parent of the current context; we don't want to look
1137 // into the pre-existing complete definition.
1138 S->setEntity(CurContext->getLookupParent());
1142 void Sema::ActOnTagFinishSkippedDefinition(SkippedDefinitionContext Context) {
1143 CurContext = static_cast<decltype(CurContext)>(Context);
1146 /// EnterDeclaratorContext - Used when we must lookup names in the context
1147 /// of a declarator's nested name specifier.
1149 void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) {
1150 // C++0x [basic.lookup.unqual]p13:
1151 // A name used in the definition of a static data member of class
1152 // X (after the qualified-id of the static member) is looked up as
1153 // if the name was used in a member function of X.
1154 // C++0x [basic.lookup.unqual]p14:
1155 // If a variable member of a namespace is defined outside of the
1156 // scope of its namespace then any name used in the definition of
1157 // the variable member (after the declarator-id) is looked up as
1158 // if the definition of the variable member occurred in its
1160 // Both of these imply that we should push a scope whose context
1161 // is the semantic context of the declaration. We can't use
1162 // PushDeclContext here because that context is not necessarily
1163 // lexically contained in the current context. Fortunately,
1164 // the containing scope should have the appropriate information.
1166 assert(!S->getEntity() && "scope already has entity");
1169 Scope *Ancestor = S->getParent();
1170 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1171 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch");
1178 void Sema::ExitDeclaratorContext(Scope *S) {
1179 assert(S->getEntity() == CurContext && "Context imbalance!");
1181 // Switch back to the lexical context. The safety of this is
1182 // enforced by an assert in EnterDeclaratorContext.
1183 Scope *Ancestor = S->getParent();
1184 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1185 CurContext = Ancestor->getEntity();
1187 // We don't need to do anything with the scope, which is going to
1191 void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) {
1192 // We assume that the caller has already called
1193 // ActOnReenterTemplateScope so getTemplatedDecl() works.
1194 FunctionDecl *FD = D->getAsFunction();
1198 // Same implementation as PushDeclContext, but enters the context
1199 // from the lexical parent, rather than the top-level class.
1200 assert(CurContext == FD->getLexicalParent() &&
1201 "The next DeclContext should be lexically contained in the current one.");
1203 S->setEntity(CurContext);
1205 for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) {
1206 ParmVarDecl *Param = FD->getParamDecl(P);
1207 // If the parameter has an identifier, then add it to the scope
1208 if (Param->getIdentifier()) {
1210 IdResolver.AddDecl(Param);
1215 void Sema::ActOnExitFunctionContext() {
1216 // Same implementation as PopDeclContext, but returns to the lexical parent,
1217 // rather than the top-level class.
1218 assert(CurContext && "DeclContext imbalance!");
1219 CurContext = CurContext->getLexicalParent();
1220 assert(CurContext && "Popped translation unit!");
1223 /// \brief Determine whether we allow overloading of the function
1224 /// PrevDecl with another declaration.
1226 /// This routine determines whether overloading is possible, not
1227 /// whether some new function is actually an overload. It will return
1228 /// true in C++ (where we can always provide overloads) or, as an
1229 /// extension, in C when the previous function is already an
1230 /// overloaded function declaration or has the "overloadable"
1232 static bool AllowOverloadingOfFunction(LookupResult &Previous,
1233 ASTContext &Context) {
1234 if (Context.getLangOpts().CPlusPlus)
1237 if (Previous.getResultKind() == LookupResult::FoundOverloaded)
1240 return (Previous.getResultKind() == LookupResult::Found
1241 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>());
1244 /// Add this decl to the scope shadowed decl chains.
1245 void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) {
1246 // Move up the scope chain until we find the nearest enclosing
1247 // non-transparent context. The declaration will be introduced into this
1249 while (S->getEntity() && S->getEntity()->isTransparentContext())
1252 // Add scoped declarations into their context, so that they can be
1253 // found later. Declarations without a context won't be inserted
1254 // into any context.
1256 CurContext->addDecl(D);
1258 // Out-of-line definitions shouldn't be pushed into scope in C++, unless they
1259 // are function-local declarations.
1260 if (getLangOpts().CPlusPlus && D->isOutOfLine() &&
1261 !D->getDeclContext()->getRedeclContext()->Equals(
1262 D->getLexicalDeclContext()->getRedeclContext()) &&
1263 !D->getLexicalDeclContext()->isFunctionOrMethod())
1266 // Template instantiations should also not be pushed into scope.
1267 if (isa<FunctionDecl>(D) &&
1268 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization())
1271 // If this replaces anything in the current scope,
1272 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()),
1273 IEnd = IdResolver.end();
1274 for (; I != IEnd; ++I) {
1275 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) {
1277 IdResolver.RemoveDecl(*I);
1279 // Should only need to replace one decl.
1286 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) {
1287 // Implicitly-generated labels may end up getting generated in an order that
1288 // isn't strictly lexical, which breaks name lookup. Be careful to insert
1289 // the label at the appropriate place in the identifier chain.
1290 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) {
1291 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext();
1292 if (IDC == CurContext) {
1293 if (!S->isDeclScope(*I))
1295 } else if (IDC->Encloses(CurContext))
1299 IdResolver.InsertDeclAfter(I, D);
1301 IdResolver.AddDecl(D);
1305 void Sema::pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name) {
1306 if (IdResolver.tryAddTopLevelDecl(D, Name) && TUScope)
1307 TUScope->AddDecl(D);
1310 bool Sema::isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S,
1311 bool AllowInlineNamespace) {
1312 return IdResolver.isDeclInScope(D, Ctx, S, AllowInlineNamespace);
1315 Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) {
1316 DeclContext *TargetDC = DC->getPrimaryContext();
1318 if (DeclContext *ScopeDC = S->getEntity())
1319 if (ScopeDC->getPrimaryContext() == TargetDC)
1321 } while ((S = S->getParent()));
1326 static bool isOutOfScopePreviousDeclaration(NamedDecl *,
1330 /// Filters out lookup results that don't fall within the given scope
1331 /// as determined by isDeclInScope.
1332 void Sema::FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S,
1333 bool ConsiderLinkage,
1334 bool AllowInlineNamespace) {
1335 LookupResult::Filter F = R.makeFilter();
1336 while (F.hasNext()) {
1337 NamedDecl *D = F.next();
1339 if (isDeclInScope(D, Ctx, S, AllowInlineNamespace))
1342 if (ConsiderLinkage && isOutOfScopePreviousDeclaration(D, Ctx, Context))
1351 static bool isUsingDecl(NamedDecl *D) {
1352 return isa<UsingShadowDecl>(D) ||
1353 isa<UnresolvedUsingTypenameDecl>(D) ||
1354 isa<UnresolvedUsingValueDecl>(D);
1357 /// Removes using shadow declarations from the lookup results.
1358 static void RemoveUsingDecls(LookupResult &R) {
1359 LookupResult::Filter F = R.makeFilter();
1361 if (isUsingDecl(F.next()))
1367 /// \brief Check for this common pattern:
1370 /// S(const S&); // DO NOT IMPLEMENT
1371 /// void operator=(const S&); // DO NOT IMPLEMENT
1374 static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) {
1375 // FIXME: Should check for private access too but access is set after we get
1377 if (D->doesThisDeclarationHaveABody())
1380 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D))
1381 return CD->isCopyConstructor();
1382 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
1383 return Method->isCopyAssignmentOperator();
1387 // We need this to handle
1390 // void *foo() { return 0; }
1393 // When we see foo we don't know if after the typedef we will get 'A' or '*A'
1394 // for example. If 'A', foo will have external linkage. If we have '*A',
1395 // foo will have no linkage. Since we can't know until we get to the end
1396 // of the typedef, this function finds out if D might have non-external linkage.
1397 // Callers should verify at the end of the TU if it D has external linkage or
1399 bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) {
1400 const DeclContext *DC = D->getDeclContext();
1401 while (!DC->isTranslationUnit()) {
1402 if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){
1403 if (!RD->hasNameForLinkage())
1406 DC = DC->getParent();
1409 return !D->isExternallyVisible();
1412 // FIXME: This needs to be refactored; some other isInMainFile users want
1414 static bool isMainFileLoc(const Sema &S, SourceLocation Loc) {
1415 if (S.TUKind != TU_Complete)
1417 return S.SourceMgr.isInMainFile(Loc);
1420 bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
1423 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>())
1426 // Ignore all entities declared within templates, and out-of-line definitions
1427 // of members of class templates.
1428 if (D->getDeclContext()->isDependentContext() ||
1429 D->getLexicalDeclContext()->isDependentContext())
1432 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1433 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1436 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
1437 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD))
1440 // 'static inline' functions are defined in headers; don't warn.
1441 if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation()))
1445 if (FD->doesThisDeclarationHaveABody() &&
1446 Context.DeclMustBeEmitted(FD))
1448 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1449 // Constants and utility variables are defined in headers with internal
1450 // linkage; don't warn. (Unlike functions, there isn't a convenient marker
1452 if (!isMainFileLoc(*this, VD->getLocation()))
1455 if (Context.DeclMustBeEmitted(VD))
1458 if (VD->isStaticDataMember() &&
1459 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1462 if (VD->isInline() && !isMainFileLoc(*this, VD->getLocation()))
1468 // Only warn for unused decls internal to the translation unit.
1469 // FIXME: This seems like a bogus check; it suppresses -Wunused-function
1470 // for inline functions defined in the main source file, for instance.
1471 return mightHaveNonExternalLinkage(D);
1474 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
1478 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1479 const FunctionDecl *First = FD->getFirstDecl();
1480 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1481 return; // First should already be in the vector.
1484 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1485 const VarDecl *First = VD->getFirstDecl();
1486 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1487 return; // First should already be in the vector.
1490 if (ShouldWarnIfUnusedFileScopedDecl(D))
1491 UnusedFileScopedDecls.push_back(D);
1494 static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
1495 if (D->isInvalidDecl())
1498 if (D->isReferenced() || D->isUsed() || D->hasAttr<UnusedAttr>() ||
1499 D->hasAttr<ObjCPreciseLifetimeAttr>())
1502 if (isa<LabelDecl>(D))
1505 // Except for labels, we only care about unused decls that are local to
1507 bool WithinFunction = D->getDeclContext()->isFunctionOrMethod();
1508 if (const auto *R = dyn_cast<CXXRecordDecl>(D->getDeclContext()))
1509 // For dependent types, the diagnostic is deferred.
1511 WithinFunction || (R->isLocalClass() && !R->isDependentType());
1512 if (!WithinFunction)
1515 if (isa<TypedefNameDecl>(D))
1518 // White-list anything that isn't a local variable.
1519 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D))
1522 // Types of valid local variables should be complete, so this should succeed.
1523 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1525 // White-list anything with an __attribute__((unused)) type.
1526 const auto *Ty = VD->getType().getTypePtr();
1528 // Only look at the outermost level of typedef.
1529 if (const TypedefType *TT = Ty->getAs<TypedefType>()) {
1530 if (TT->getDecl()->hasAttr<UnusedAttr>())
1534 // If we failed to complete the type for some reason, or if the type is
1535 // dependent, don't diagnose the variable.
1536 if (Ty->isIncompleteType() || Ty->isDependentType())
1539 // Look at the element type to ensure that the warning behaviour is
1540 // consistent for both scalars and arrays.
1541 Ty = Ty->getBaseElementTypeUnsafe();
1543 if (const TagType *TT = Ty->getAs<TagType>()) {
1544 const TagDecl *Tag = TT->getDecl();
1545 if (Tag->hasAttr<UnusedAttr>())
1548 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) {
1549 if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>())
1552 if (const Expr *Init = VD->getInit()) {
1553 if (const ExprWithCleanups *Cleanups =
1554 dyn_cast<ExprWithCleanups>(Init))
1555 Init = Cleanups->getSubExpr();
1556 const CXXConstructExpr *Construct =
1557 dyn_cast<CXXConstructExpr>(Init);
1558 if (Construct && !Construct->isElidable()) {
1559 CXXConstructorDecl *CD = Construct->getConstructor();
1560 if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>())
1567 // TODO: __attribute__((unused)) templates?
1573 static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx,
1575 if (isa<LabelDecl>(D)) {
1576 SourceLocation AfterColon = Lexer::findLocationAfterToken(D->getLocEnd(),
1577 tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(), true);
1578 if (AfterColon.isInvalid())
1580 Hint = FixItHint::CreateRemoval(CharSourceRange::
1581 getCharRange(D->getLocStart(), AfterColon));
1585 void Sema::DiagnoseUnusedNestedTypedefs(const RecordDecl *D) {
1586 if (D->getTypeForDecl()->isDependentType())
1589 for (auto *TmpD : D->decls()) {
1590 if (const auto *T = dyn_cast<TypedefNameDecl>(TmpD))
1591 DiagnoseUnusedDecl(T);
1592 else if(const auto *R = dyn_cast<RecordDecl>(TmpD))
1593 DiagnoseUnusedNestedTypedefs(R);
1597 /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used
1598 /// unless they are marked attr(unused).
1599 void Sema::DiagnoseUnusedDecl(const NamedDecl *D) {
1600 if (!ShouldDiagnoseUnusedDecl(D))
1603 if (auto *TD = dyn_cast<TypedefNameDecl>(D)) {
1604 // typedefs can be referenced later on, so the diagnostics are emitted
1605 // at end-of-translation-unit.
1606 UnusedLocalTypedefNameCandidates.insert(TD);
1611 GenerateFixForUnusedDecl(D, Context, Hint);
1614 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable())
1615 DiagID = diag::warn_unused_exception_param;
1616 else if (isa<LabelDecl>(D))
1617 DiagID = diag::warn_unused_label;
1619 DiagID = diag::warn_unused_variable;
1621 Diag(D->getLocation(), DiagID) << D->getDeclName() << Hint;
1624 static void CheckPoppedLabel(LabelDecl *L, Sema &S) {
1625 // Verify that we have no forward references left. If so, there was a goto
1626 // or address of a label taken, but no definition of it. Label fwd
1627 // definitions are indicated with a null substmt which is also not a resolved
1628 // MS inline assembly label name.
1629 bool Diagnose = false;
1630 if (L->isMSAsmLabel())
1631 Diagnose = !L->isResolvedMSAsmLabel();
1633 Diagnose = L->getStmt() == nullptr;
1635 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName();
1638 void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) {
1639 S->mergeNRVOIntoParent();
1641 if (S->decl_empty()) return;
1642 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) &&
1643 "Scope shouldn't contain decls!");
1645 for (auto *TmpD : S->decls()) {
1646 assert(TmpD && "This decl didn't get pushed??");
1648 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?");
1649 NamedDecl *D = cast<NamedDecl>(TmpD);
1651 if (!D->getDeclName()) continue;
1653 // Diagnose unused variables in this scope.
1654 if (!S->hasUnrecoverableErrorOccurred()) {
1655 DiagnoseUnusedDecl(D);
1656 if (const auto *RD = dyn_cast<RecordDecl>(D))
1657 DiagnoseUnusedNestedTypedefs(RD);
1660 // If this was a forward reference to a label, verify it was defined.
1661 if (LabelDecl *LD = dyn_cast<LabelDecl>(D))
1662 CheckPoppedLabel(LD, *this);
1664 // Remove this name from our lexical scope, and warn on it if we haven't
1666 IdResolver.RemoveDecl(D);
1667 auto ShadowI = ShadowingDecls.find(D);
1668 if (ShadowI != ShadowingDecls.end()) {
1669 if (const auto *FD = dyn_cast<FieldDecl>(ShadowI->second)) {
1670 Diag(D->getLocation(), diag::warn_ctor_parm_shadows_field)
1671 << D << FD << FD->getParent();
1672 Diag(FD->getLocation(), diag::note_previous_declaration);
1674 ShadowingDecls.erase(ShadowI);
1679 /// \brief Look for an Objective-C class in the translation unit.
1681 /// \param Id The name of the Objective-C class we're looking for. If
1682 /// typo-correction fixes this name, the Id will be updated
1683 /// to the fixed name.
1685 /// \param IdLoc The location of the name in the translation unit.
1687 /// \param DoTypoCorrection If true, this routine will attempt typo correction
1688 /// if there is no class with the given name.
1690 /// \returns The declaration of the named Objective-C class, or NULL if the
1691 /// class could not be found.
1692 ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id,
1693 SourceLocation IdLoc,
1694 bool DoTypoCorrection) {
1695 // The third "scope" argument is 0 since we aren't enabling lazy built-in
1696 // creation from this context.
1697 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName);
1699 if (!IDecl && DoTypoCorrection) {
1700 // Perform typo correction at the given location, but only if we
1701 // find an Objective-C class name.
1702 if (TypoCorrection C = CorrectTypo(
1703 DeclarationNameInfo(Id, IdLoc), LookupOrdinaryName, TUScope, nullptr,
1704 llvm::make_unique<DeclFilterCCC<ObjCInterfaceDecl>>(),
1705 CTK_ErrorRecovery)) {
1706 diagnoseTypo(C, PDiag(diag::err_undef_interface_suggest) << Id);
1707 IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>();
1708 Id = IDecl->getIdentifier();
1711 ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl);
1712 // This routine must always return a class definition, if any.
1713 if (Def && Def->getDefinition())
1714 Def = Def->getDefinition();
1718 /// getNonFieldDeclScope - Retrieves the innermost scope, starting
1719 /// from S, where a non-field would be declared. This routine copes
1720 /// with the difference between C and C++ scoping rules in structs and
1721 /// unions. For example, the following code is well-formed in C but
1722 /// ill-formed in C++:
1728 /// void test_S6() {
1733 /// For the declaration of BAR, this routine will return a different
1734 /// scope. The scope S will be the scope of the unnamed enumeration
1735 /// within S6. In C++, this routine will return the scope associated
1736 /// with S6, because the enumeration's scope is a transparent
1737 /// context but structures can contain non-field names. In C, this
1738 /// routine will return the translation unit scope, since the
1739 /// enumeration's scope is a transparent context and structures cannot
1740 /// contain non-field names.
1741 Scope *Sema::getNonFieldDeclScope(Scope *S) {
1742 while (((S->getFlags() & Scope::DeclScope) == 0) ||
1743 (S->getEntity() && S->getEntity()->isTransparentContext()) ||
1744 (S->isClassScope() && !getLangOpts().CPlusPlus))
1749 /// \brief Looks up the declaration of "struct objc_super" and
1750 /// saves it for later use in building builtin declaration of
1751 /// objc_msgSendSuper and objc_msgSendSuper_stret. If no such
1752 /// pre-existing declaration exists no action takes place.
1753 static void LookupPredefedObjCSuperType(Sema &ThisSema, Scope *S,
1754 IdentifierInfo *II) {
1755 if (!II->isStr("objc_msgSendSuper"))
1757 ASTContext &Context = ThisSema.Context;
1759 LookupResult Result(ThisSema, &Context.Idents.get("objc_super"),
1760 SourceLocation(), Sema::LookupTagName);
1761 ThisSema.LookupName(Result, S);
1762 if (Result.getResultKind() == LookupResult::Found)
1763 if (const TagDecl *TD = Result.getAsSingle<TagDecl>())
1764 Context.setObjCSuperType(Context.getTagDeclType(TD));
1767 static StringRef getHeaderName(ASTContext::GetBuiltinTypeError Error) {
1769 case ASTContext::GE_None:
1771 case ASTContext::GE_Missing_stdio:
1773 case ASTContext::GE_Missing_setjmp:
1775 case ASTContext::GE_Missing_ucontext:
1776 return "ucontext.h";
1778 llvm_unreachable("unhandled error kind");
1781 /// LazilyCreateBuiltin - The specified Builtin-ID was first used at
1782 /// file scope. lazily create a decl for it. ForRedeclaration is true
1783 /// if we're creating this built-in in anticipation of redeclaring the
1785 NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID,
1786 Scope *S, bool ForRedeclaration,
1787 SourceLocation Loc) {
1788 LookupPredefedObjCSuperType(*this, S, II);
1790 ASTContext::GetBuiltinTypeError Error;
1791 QualType R = Context.GetBuiltinType(ID, Error);
1793 if (ForRedeclaration)
1794 Diag(Loc, diag::warn_implicit_decl_requires_sysheader)
1795 << getHeaderName(Error) << Context.BuiltinInfo.getName(ID);
1799 if (!ForRedeclaration &&
1800 (Context.BuiltinInfo.isPredefinedLibFunction(ID) ||
1801 Context.BuiltinInfo.isHeaderDependentFunction(ID))) {
1802 Diag(Loc, diag::ext_implicit_lib_function_decl)
1803 << Context.BuiltinInfo.getName(ID) << R;
1804 if (Context.BuiltinInfo.getHeaderName(ID) &&
1805 !Diags.isIgnored(diag::ext_implicit_lib_function_decl, Loc))
1806 Diag(Loc, diag::note_include_header_or_declare)
1807 << Context.BuiltinInfo.getHeaderName(ID)
1808 << Context.BuiltinInfo.getName(ID);
1814 DeclContext *Parent = Context.getTranslationUnitDecl();
1815 if (getLangOpts().CPlusPlus) {
1816 LinkageSpecDecl *CLinkageDecl =
1817 LinkageSpecDecl::Create(Context, Parent, Loc, Loc,
1818 LinkageSpecDecl::lang_c, false);
1819 CLinkageDecl->setImplicit();
1820 Parent->addDecl(CLinkageDecl);
1821 Parent = CLinkageDecl;
1824 FunctionDecl *New = FunctionDecl::Create(Context,
1826 Loc, Loc, II, R, /*TInfo=*/nullptr,
1829 R->isFunctionProtoType());
1832 // Create Decl objects for each parameter, adding them to the
1834 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) {
1835 SmallVector<ParmVarDecl*, 16> Params;
1836 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
1838 ParmVarDecl::Create(Context, New, SourceLocation(), SourceLocation(),
1839 nullptr, FT->getParamType(i), /*TInfo=*/nullptr,
1841 parm->setScopeInfo(0, i);
1842 Params.push_back(parm);
1844 New->setParams(Params);
1847 AddKnownFunctionAttributes(New);
1848 RegisterLocallyScopedExternCDecl(New, S);
1850 // TUScope is the translation-unit scope to insert this function into.
1851 // FIXME: This is hideous. We need to teach PushOnScopeChains to
1852 // relate Scopes to DeclContexts, and probably eliminate CurContext
1853 // entirely, but we're not there yet.
1854 DeclContext *SavedContext = CurContext;
1855 CurContext = Parent;
1856 PushOnScopeChains(New, TUScope);
1857 CurContext = SavedContext;
1861 /// Typedef declarations don't have linkage, but they still denote the same
1862 /// entity if their types are the same.
1863 /// FIXME: This is notionally doing the same thing as ASTReaderDecl's
1865 static void filterNonConflictingPreviousTypedefDecls(Sema &S,
1866 TypedefNameDecl *Decl,
1867 LookupResult &Previous) {
1868 // This is only interesting when modules are enabled.
1869 if (!S.getLangOpts().Modules && !S.getLangOpts().ModulesLocalVisibility)
1872 // Empty sets are uninteresting.
1873 if (Previous.empty())
1876 LookupResult::Filter Filter = Previous.makeFilter();
1877 while (Filter.hasNext()) {
1878 NamedDecl *Old = Filter.next();
1880 // Non-hidden declarations are never ignored.
1881 if (S.isVisible(Old))
1884 // Declarations of the same entity are not ignored, even if they have
1885 // different linkages.
1886 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
1887 if (S.Context.hasSameType(OldTD->getUnderlyingType(),
1888 Decl->getUnderlyingType()))
1891 // If both declarations give a tag declaration a typedef name for linkage
1892 // purposes, then they declare the same entity.
1893 if (S.getLangOpts().CPlusPlus &&
1894 OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true) &&
1895 Decl->getAnonDeclWithTypedefName())
1905 bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) {
1907 if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old))
1908 OldType = OldTypedef->getUnderlyingType();
1910 OldType = Context.getTypeDeclType(Old);
1911 QualType NewType = New->getUnderlyingType();
1913 if (NewType->isVariablyModifiedType()) {
1914 // Must not redefine a typedef with a variably-modified type.
1915 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1916 Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef)
1918 if (Old->getLocation().isValid())
1919 Diag(Old->getLocation(), diag::note_previous_definition);
1920 New->setInvalidDecl();
1924 if (OldType != NewType &&
1925 !OldType->isDependentType() &&
1926 !NewType->isDependentType() &&
1927 !Context.hasSameType(OldType, NewType)) {
1928 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1929 Diag(New->getLocation(), diag::err_redefinition_different_typedef)
1930 << Kind << NewType << OldType;
1931 if (Old->getLocation().isValid())
1932 Diag(Old->getLocation(), diag::note_previous_definition);
1933 New->setInvalidDecl();
1939 /// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the
1940 /// same name and scope as a previous declaration 'Old'. Figure out
1941 /// how to resolve this situation, merging decls or emitting
1942 /// diagnostics as appropriate. If there was an error, set New to be invalid.
1944 void Sema::MergeTypedefNameDecl(Scope *S, TypedefNameDecl *New,
1945 LookupResult &OldDecls) {
1946 // If the new decl is known invalid already, don't bother doing any
1948 if (New->isInvalidDecl()) return;
1950 // Allow multiple definitions for ObjC built-in typedefs.
1951 // FIXME: Verify the underlying types are equivalent!
1952 if (getLangOpts().ObjC1) {
1953 const IdentifierInfo *TypeID = New->getIdentifier();
1954 switch (TypeID->getLength()) {
1958 if (!TypeID->isStr("id"))
1960 QualType T = New->getUnderlyingType();
1961 if (!T->isPointerType())
1963 if (!T->isVoidPointerType()) {
1964 QualType PT = T->getAs<PointerType>()->getPointeeType();
1965 if (!PT->isStructureType())
1968 Context.setObjCIdRedefinitionType(T);
1969 // Install the built-in type for 'id', ignoring the current definition.
1970 New->setTypeForDecl(Context.getObjCIdType().getTypePtr());
1974 if (!TypeID->isStr("Class"))
1976 Context.setObjCClassRedefinitionType(New->getUnderlyingType());
1977 // Install the built-in type for 'Class', ignoring the current definition.
1978 New->setTypeForDecl(Context.getObjCClassType().getTypePtr());
1981 if (!TypeID->isStr("SEL"))
1983 Context.setObjCSelRedefinitionType(New->getUnderlyingType());
1984 // Install the built-in type for 'SEL', ignoring the current definition.
1985 New->setTypeForDecl(Context.getObjCSelType().getTypePtr());
1988 // Fall through - the typedef name was not a builtin type.
1991 // Verify the old decl was also a type.
1992 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>();
1994 Diag(New->getLocation(), diag::err_redefinition_different_kind)
1995 << New->getDeclName();
1997 NamedDecl *OldD = OldDecls.getRepresentativeDecl();
1998 if (OldD->getLocation().isValid())
1999 Diag(OldD->getLocation(), diag::note_previous_definition);
2001 return New->setInvalidDecl();
2004 // If the old declaration is invalid, just give up here.
2005 if (Old->isInvalidDecl())
2006 return New->setInvalidDecl();
2008 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old)) {
2009 auto *OldTag = OldTD->getAnonDeclWithTypedefName(/*AnyRedecl*/true);
2010 auto *NewTag = New->getAnonDeclWithTypedefName();
2011 NamedDecl *Hidden = nullptr;
2012 if (getLangOpts().CPlusPlus && OldTag && NewTag &&
2013 OldTag->getCanonicalDecl() != NewTag->getCanonicalDecl() &&
2014 !hasVisibleDefinition(OldTag, &Hidden)) {
2015 // There is a definition of this tag, but it is not visible. Use it
2016 // instead of our tag.
2017 New->setTypeForDecl(OldTD->getTypeForDecl());
2018 if (OldTD->isModed())
2019 New->setModedTypeSourceInfo(OldTD->getTypeSourceInfo(),
2020 OldTD->getUnderlyingType());
2022 New->setTypeSourceInfo(OldTD->getTypeSourceInfo());
2024 // Make the old tag definition visible.
2025 makeMergedDefinitionVisible(Hidden, NewTag->getLocation());
2027 // If this was an unscoped enumeration, yank all of its enumerators
2028 // out of the scope.
2029 if (isa<EnumDecl>(NewTag)) {
2030 Scope *EnumScope = getNonFieldDeclScope(S);
2031 for (auto *D : NewTag->decls()) {
2032 auto *ED = cast<EnumConstantDecl>(D);
2033 assert(EnumScope->isDeclScope(ED));
2034 EnumScope->RemoveDecl(ED);
2035 IdResolver.RemoveDecl(ED);
2036 ED->getLexicalDeclContext()->removeDecl(ED);
2042 // If the typedef types are not identical, reject them in all languages and
2043 // with any extensions enabled.
2044 if (isIncompatibleTypedef(Old, New))
2047 // The types match. Link up the redeclaration chain and merge attributes if
2048 // the old declaration was a typedef.
2049 if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) {
2050 New->setPreviousDecl(Typedef);
2051 mergeDeclAttributes(New, Old);
2054 if (getLangOpts().MicrosoftExt)
2057 if (getLangOpts().CPlusPlus) {
2058 // C++ [dcl.typedef]p2:
2059 // In a given non-class scope, a typedef specifier can be used to
2060 // redefine the name of any type declared in that scope to refer
2061 // to the type to which it already refers.
2062 if (!isa<CXXRecordDecl>(CurContext))
2065 // C++0x [dcl.typedef]p4:
2066 // In a given class scope, a typedef specifier can be used to redefine
2067 // any class-name declared in that scope that is not also a typedef-name
2068 // to refer to the type to which it already refers.
2070 // This wording came in via DR424, which was a correction to the
2071 // wording in DR56, which accidentally banned code like:
2074 // typedef struct A { } A;
2077 // in the C++03 standard. We implement the C++0x semantics, which
2078 // allow the above but disallow
2085 // since that was the intent of DR56.
2086 if (!isa<TypedefNameDecl>(Old))
2089 Diag(New->getLocation(), diag::err_redefinition)
2090 << New->getDeclName();
2091 Diag(Old->getLocation(), diag::note_previous_definition);
2092 return New->setInvalidDecl();
2095 // Modules always permit redefinition of typedefs, as does C11.
2096 if (getLangOpts().Modules || getLangOpts().C11)
2099 // If we have a redefinition of a typedef in C, emit a warning. This warning
2100 // is normally mapped to an error, but can be controlled with
2101 // -Wtypedef-redefinition. If either the original or the redefinition is
2102 // in a system header, don't emit this for compatibility with GCC.
2103 if (getDiagnostics().getSuppressSystemWarnings() &&
2104 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) ||
2105 Context.getSourceManager().isInSystemHeader(New->getLocation())))
2108 Diag(New->getLocation(), diag::ext_redefinition_of_typedef)
2109 << New->getDeclName();
2110 Diag(Old->getLocation(), diag::note_previous_definition);
2113 /// DeclhasAttr - returns true if decl Declaration already has the target
2115 static bool DeclHasAttr(const Decl *D, const Attr *A) {
2116 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A);
2117 const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A);
2118 for (const auto *i : D->attrs())
2119 if (i->getKind() == A->getKind()) {
2121 if (Ann->getAnnotation() == cast<AnnotateAttr>(i)->getAnnotation())
2125 // FIXME: Don't hardcode this check
2126 if (OA && isa<OwnershipAttr>(i))
2127 return OA->getOwnKind() == cast<OwnershipAttr>(i)->getOwnKind();
2134 static bool isAttributeTargetADefinition(Decl *D) {
2135 if (VarDecl *VD = dyn_cast<VarDecl>(D))
2136 return VD->isThisDeclarationADefinition();
2137 if (TagDecl *TD = dyn_cast<TagDecl>(D))
2138 return TD->isCompleteDefinition() || TD->isBeingDefined();
2142 /// Merge alignment attributes from \p Old to \p New, taking into account the
2143 /// special semantics of C11's _Alignas specifier and C++11's alignas attribute.
2145 /// \return \c true if any attributes were added to \p New.
2146 static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) {
2147 // Look for alignas attributes on Old, and pick out whichever attribute
2148 // specifies the strictest alignment requirement.
2149 AlignedAttr *OldAlignasAttr = nullptr;
2150 AlignedAttr *OldStrictestAlignAttr = nullptr;
2151 unsigned OldAlign = 0;
2152 for (auto *I : Old->specific_attrs<AlignedAttr>()) {
2153 // FIXME: We have no way of representing inherited dependent alignments
2155 // template<int A, int B> struct alignas(A) X;
2156 // template<int A, int B> struct alignas(B) X {};
2157 // For now, we just ignore any alignas attributes which are not on the
2158 // definition in such a case.
2159 if (I->isAlignmentDependent())
2165 unsigned Align = I->getAlignment(S.Context);
2166 if (Align > OldAlign) {
2168 OldStrictestAlignAttr = I;
2172 // Look for alignas attributes on New.
2173 AlignedAttr *NewAlignasAttr = nullptr;
2174 unsigned NewAlign = 0;
2175 for (auto *I : New->specific_attrs<AlignedAttr>()) {
2176 if (I->isAlignmentDependent())
2182 unsigned Align = I->getAlignment(S.Context);
2183 if (Align > NewAlign)
2187 if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) {
2188 // Both declarations have 'alignas' attributes. We require them to match.
2189 // C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but
2190 // fall short. (If two declarations both have alignas, they must both match
2191 // every definition, and so must match each other if there is a definition.)
2193 // If either declaration only contains 'alignas(0)' specifiers, then it
2194 // specifies the natural alignment for the type.
2195 if (OldAlign == 0 || NewAlign == 0) {
2197 if (ValueDecl *VD = dyn_cast<ValueDecl>(New))
2200 Ty = S.Context.getTagDeclType(cast<TagDecl>(New));
2203 OldAlign = S.Context.getTypeAlign(Ty);
2205 NewAlign = S.Context.getTypeAlign(Ty);
2208 if (OldAlign != NewAlign) {
2209 S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch)
2210 << (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity()
2211 << (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity();
2212 S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration);
2216 if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) {
2217 // C++11 [dcl.align]p6:
2218 // if any declaration of an entity has an alignment-specifier,
2219 // every defining declaration of that entity shall specify an
2220 // equivalent alignment.
2222 // If the definition of an object does not have an alignment
2223 // specifier, any other declaration of that object shall also
2224 // have no alignment specifier.
2225 S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition)
2227 S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration)
2231 bool AnyAdded = false;
2233 // Ensure we have an attribute representing the strictest alignment.
2234 if (OldAlign > NewAlign) {
2235 AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context);
2236 Clone->setInherited(true);
2237 New->addAttr(Clone);
2241 // Ensure we have an alignas attribute if the old declaration had one.
2242 if (OldAlignasAttr && !NewAlignasAttr &&
2243 !(AnyAdded && OldStrictestAlignAttr->isAlignas())) {
2244 AlignedAttr *Clone = OldAlignasAttr->clone(S.Context);
2245 Clone->setInherited(true);
2246 New->addAttr(Clone);
2253 static bool mergeDeclAttribute(Sema &S, NamedDecl *D,
2254 const InheritableAttr *Attr,
2255 Sema::AvailabilityMergeKind AMK) {
2256 // This function copies an attribute Attr from a previous declaration to the
2257 // new declaration D if the new declaration doesn't itself have that attribute
2258 // yet or if that attribute allows duplicates.
2259 // If you're adding a new attribute that requires logic different from
2260 // "use explicit attribute on decl if present, else use attribute from
2261 // previous decl", for example if the attribute needs to be consistent
2262 // between redeclarations, you need to call a custom merge function here.
2263 InheritableAttr *NewAttr = nullptr;
2264 unsigned AttrSpellingListIndex = Attr->getSpellingListIndex();
2265 if (const auto *AA = dyn_cast<AvailabilityAttr>(Attr))
2266 NewAttr = S.mergeAvailabilityAttr(D, AA->getRange(), AA->getPlatform(),
2267 AA->isImplicit(), AA->getIntroduced(),
2268 AA->getDeprecated(),
2269 AA->getObsoleted(), AA->getUnavailable(),
2270 AA->getMessage(), AA->getStrict(),
2271 AA->getReplacement(), AMK,
2272 AttrSpellingListIndex);
2273 else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr))
2274 NewAttr = S.mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2275 AttrSpellingListIndex);
2276 else if (const auto *VA = dyn_cast<TypeVisibilityAttr>(Attr))
2277 NewAttr = S.mergeTypeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2278 AttrSpellingListIndex);
2279 else if (const auto *ImportA = dyn_cast<DLLImportAttr>(Attr))
2280 NewAttr = S.mergeDLLImportAttr(D, ImportA->getRange(),
2281 AttrSpellingListIndex);
2282 else if (const auto *ExportA = dyn_cast<DLLExportAttr>(Attr))
2283 NewAttr = S.mergeDLLExportAttr(D, ExportA->getRange(),
2284 AttrSpellingListIndex);
2285 else if (const auto *FA = dyn_cast<FormatAttr>(Attr))
2286 NewAttr = S.mergeFormatAttr(D, FA->getRange(), FA->getType(),
2287 FA->getFormatIdx(), FA->getFirstArg(),
2288 AttrSpellingListIndex);
2289 else if (const auto *SA = dyn_cast<SectionAttr>(Attr))
2290 NewAttr = S.mergeSectionAttr(D, SA->getRange(), SA->getName(),
2291 AttrSpellingListIndex);
2292 else if (const auto *IA = dyn_cast<MSInheritanceAttr>(Attr))
2293 NewAttr = S.mergeMSInheritanceAttr(D, IA->getRange(), IA->getBestCase(),
2294 AttrSpellingListIndex,
2295 IA->getSemanticSpelling());
2296 else if (const auto *AA = dyn_cast<AlwaysInlineAttr>(Attr))
2297 NewAttr = S.mergeAlwaysInlineAttr(D, AA->getRange(),
2298 &S.Context.Idents.get(AA->getSpelling()),
2299 AttrSpellingListIndex);
2300 else if (S.getLangOpts().CUDA && isa<FunctionDecl>(D) &&
2301 (isa<CUDAHostAttr>(Attr) || isa<CUDADeviceAttr>(Attr) ||
2302 isa<CUDAGlobalAttr>(Attr))) {
2303 // CUDA target attributes are part of function signature for
2304 // overloading purposes and must not be merged.
2306 } else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr))
2307 NewAttr = S.mergeMinSizeAttr(D, MA->getRange(), AttrSpellingListIndex);
2308 else if (const auto *OA = dyn_cast<OptimizeNoneAttr>(Attr))
2309 NewAttr = S.mergeOptimizeNoneAttr(D, OA->getRange(), AttrSpellingListIndex);
2310 else if (const auto *InternalLinkageA = dyn_cast<InternalLinkageAttr>(Attr))
2311 NewAttr = S.mergeInternalLinkageAttr(
2312 D, InternalLinkageA->getRange(),
2313 &S.Context.Idents.get(InternalLinkageA->getSpelling()),
2314 AttrSpellingListIndex);
2315 else if (const auto *CommonA = dyn_cast<CommonAttr>(Attr))
2316 NewAttr = S.mergeCommonAttr(D, CommonA->getRange(),
2317 &S.Context.Idents.get(CommonA->getSpelling()),
2318 AttrSpellingListIndex);
2319 else if (isa<AlignedAttr>(Attr))
2320 // AlignedAttrs are handled separately, because we need to handle all
2321 // such attributes on a declaration at the same time.
2323 else if ((isa<DeprecatedAttr>(Attr) || isa<UnavailableAttr>(Attr)) &&
2324 (AMK == Sema::AMK_Override ||
2325 AMK == Sema::AMK_ProtocolImplementation))
2327 else if (const auto *UA = dyn_cast<UuidAttr>(Attr))
2328 NewAttr = S.mergeUuidAttr(D, UA->getRange(), AttrSpellingListIndex,
2330 else if (Attr->duplicatesAllowed() || !DeclHasAttr(D, Attr))
2331 NewAttr = cast<InheritableAttr>(Attr->clone(S.Context));
2334 NewAttr->setInherited(true);
2335 D->addAttr(NewAttr);
2336 if (isa<MSInheritanceAttr>(NewAttr))
2337 S.Consumer.AssignInheritanceModel(cast<CXXRecordDecl>(D));
2344 static const Decl *getDefinition(const Decl *D) {
2345 if (const TagDecl *TD = dyn_cast<TagDecl>(D))
2346 return TD->getDefinition();
2347 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
2348 const VarDecl *Def = VD->getDefinition();
2351 return VD->getActingDefinition();
2353 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
2354 return FD->getDefinition();
2358 static bool hasAttribute(const Decl *D, attr::Kind Kind) {
2359 for (const auto *Attribute : D->attrs())
2360 if (Attribute->getKind() == Kind)
2365 /// checkNewAttributesAfterDef - If we already have a definition, check that
2366 /// there are no new attributes in this declaration.
2367 static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) {
2368 if (!New->hasAttrs())
2371 const Decl *Def = getDefinition(Old);
2372 if (!Def || Def == New)
2375 AttrVec &NewAttributes = New->getAttrs();
2376 for (unsigned I = 0, E = NewAttributes.size(); I != E;) {
2377 const Attr *NewAttribute = NewAttributes[I];
2379 if (isa<AliasAttr>(NewAttribute) || isa<IFuncAttr>(NewAttribute)) {
2380 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(New)) {
2381 Sema::SkipBodyInfo SkipBody;
2382 S.CheckForFunctionRedefinition(FD, cast<FunctionDecl>(Def), &SkipBody);
2384 // If we're skipping this definition, drop the "alias" attribute.
2385 if (SkipBody.ShouldSkip) {
2386 NewAttributes.erase(NewAttributes.begin() + I);
2391 VarDecl *VD = cast<VarDecl>(New);
2392 unsigned Diag = cast<VarDecl>(Def)->isThisDeclarationADefinition() ==
2393 VarDecl::TentativeDefinition
2394 ? diag::err_alias_after_tentative
2395 : diag::err_redefinition;
2396 S.Diag(VD->getLocation(), Diag) << VD->getDeclName();
2397 S.Diag(Def->getLocation(), diag::note_previous_definition);
2398 VD->setInvalidDecl();
2404 if (const VarDecl *VD = dyn_cast<VarDecl>(Def)) {
2405 // Tentative definitions are only interesting for the alias check above.
2406 if (VD->isThisDeclarationADefinition() != VarDecl::Definition) {
2412 if (hasAttribute(Def, NewAttribute->getKind())) {
2414 continue; // regular attr merging will take care of validating this.
2417 if (isa<C11NoReturnAttr>(NewAttribute)) {
2418 // C's _Noreturn is allowed to be added to a function after it is defined.
2421 } else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) {
2422 if (AA->isAlignas()) {
2423 // C++11 [dcl.align]p6:
2424 // if any declaration of an entity has an alignment-specifier,
2425 // every defining declaration of that entity shall specify an
2426 // equivalent alignment.
2428 // If the definition of an object does not have an alignment
2429 // specifier, any other declaration of that object shall also
2430 // have no alignment specifier.
2431 S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition)
2433 S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration)
2435 NewAttributes.erase(NewAttributes.begin() + I);
2441 S.Diag(NewAttribute->getLocation(),
2442 diag::warn_attribute_precede_definition);
2443 S.Diag(Def->getLocation(), diag::note_previous_definition);
2444 NewAttributes.erase(NewAttributes.begin() + I);
2449 /// mergeDeclAttributes - Copy attributes from the Old decl to the New one.
2450 void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old,
2451 AvailabilityMergeKind AMK) {
2452 if (UsedAttr *OldAttr = Old->getMostRecentDecl()->getAttr<UsedAttr>()) {
2453 UsedAttr *NewAttr = OldAttr->clone(Context);
2454 NewAttr->setInherited(true);
2455 New->addAttr(NewAttr);
2458 if (!Old->hasAttrs() && !New->hasAttrs())
2461 // Attributes declared post-definition are currently ignored.
2462 checkNewAttributesAfterDef(*this, New, Old);
2464 if (AsmLabelAttr *NewA = New->getAttr<AsmLabelAttr>()) {
2465 if (AsmLabelAttr *OldA = Old->getAttr<AsmLabelAttr>()) {
2466 if (OldA->getLabel() != NewA->getLabel()) {
2467 // This redeclaration changes __asm__ label.
2468 Diag(New->getLocation(), diag::err_different_asm_label);
2469 Diag(OldA->getLocation(), diag::note_previous_declaration);
2471 } else if (Old->isUsed()) {
2472 // This redeclaration adds an __asm__ label to a declaration that has
2473 // already been ODR-used.
2474 Diag(New->getLocation(), diag::err_late_asm_label_name)
2475 << isa<FunctionDecl>(Old) << New->getAttr<AsmLabelAttr>()->getRange();
2479 // Re-declaration cannot add abi_tag's.
2480 if (const auto *NewAbiTagAttr = New->getAttr<AbiTagAttr>()) {
2481 if (const auto *OldAbiTagAttr = Old->getAttr<AbiTagAttr>()) {
2482 for (const auto &NewTag : NewAbiTagAttr->tags()) {
2483 if (std::find(OldAbiTagAttr->tags_begin(), OldAbiTagAttr->tags_end(),
2484 NewTag) == OldAbiTagAttr->tags_end()) {
2485 Diag(NewAbiTagAttr->getLocation(),
2486 diag::err_new_abi_tag_on_redeclaration)
2488 Diag(OldAbiTagAttr->getLocation(), diag::note_previous_declaration);
2492 Diag(NewAbiTagAttr->getLocation(), diag::err_abi_tag_on_redeclaration);
2493 Diag(Old->getLocation(), diag::note_previous_declaration);
2497 if (!Old->hasAttrs())
2500 bool foundAny = New->hasAttrs();
2502 // Ensure that any moving of objects within the allocated map is done before
2504 if (!foundAny) New->setAttrs(AttrVec());
2506 for (auto *I : Old->specific_attrs<InheritableAttr>()) {
2507 // Ignore deprecated/unavailable/availability attributes if requested.
2508 AvailabilityMergeKind LocalAMK = AMK_None;
2509 if (isa<DeprecatedAttr>(I) ||
2510 isa<UnavailableAttr>(I) ||
2511 isa<AvailabilityAttr>(I)) {
2516 case AMK_Redeclaration:
2518 case AMK_ProtocolImplementation:
2525 if (isa<UsedAttr>(I))
2528 if (mergeDeclAttribute(*this, New, I, LocalAMK))
2532 if (mergeAlignedAttrs(*this, New, Old))
2535 if (!foundAny) New->dropAttrs();
2538 /// mergeParamDeclAttributes - Copy attributes from the old parameter
2540 static void mergeParamDeclAttributes(ParmVarDecl *newDecl,
2541 const ParmVarDecl *oldDecl,
2543 // C++11 [dcl.attr.depend]p2:
2544 // The first declaration of a function shall specify the
2545 // carries_dependency attribute for its declarator-id if any declaration
2546 // of the function specifies the carries_dependency attribute.
2547 const CarriesDependencyAttr *CDA = newDecl->getAttr<CarriesDependencyAttr>();
2548 if (CDA && !oldDecl->hasAttr<CarriesDependencyAttr>()) {
2549 S.Diag(CDA->getLocation(),
2550 diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/;
2551 // Find the first declaration of the parameter.
2552 // FIXME: Should we build redeclaration chains for function parameters?
2553 const FunctionDecl *FirstFD =
2554 cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDecl();
2555 const ParmVarDecl *FirstVD =
2556 FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex());
2557 S.Diag(FirstVD->getLocation(),
2558 diag::note_carries_dependency_missing_first_decl) << 1/*Param*/;
2561 if (!oldDecl->hasAttrs())
2564 bool foundAny = newDecl->hasAttrs();
2566 // Ensure that any moving of objects within the allocated map is
2567 // done before we process them.
2568 if (!foundAny) newDecl->setAttrs(AttrVec());
2570 for (const auto *I : oldDecl->specific_attrs<InheritableParamAttr>()) {
2571 if (!DeclHasAttr(newDecl, I)) {
2572 InheritableAttr *newAttr =
2573 cast<InheritableParamAttr>(I->clone(S.Context));
2574 newAttr->setInherited(true);
2575 newDecl->addAttr(newAttr);
2580 if (!foundAny) newDecl->dropAttrs();
2583 static void mergeParamDeclTypes(ParmVarDecl *NewParam,
2584 const ParmVarDecl *OldParam,
2586 if (auto Oldnullability = OldParam->getType()->getNullability(S.Context)) {
2587 if (auto Newnullability = NewParam->getType()->getNullability(S.Context)) {
2588 if (*Oldnullability != *Newnullability) {
2589 S.Diag(NewParam->getLocation(), diag::warn_mismatched_nullability_attr)
2590 << DiagNullabilityKind(
2592 ((NewParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2594 << DiagNullabilityKind(
2596 ((OldParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2598 S.Diag(OldParam->getLocation(), diag::note_previous_declaration);
2601 QualType NewT = NewParam->getType();
2602 NewT = S.Context.getAttributedType(
2603 AttributedType::getNullabilityAttrKind(*Oldnullability),
2605 NewParam->setType(NewT);
2612 /// Used in MergeFunctionDecl to keep track of function parameters in
2614 struct GNUCompatibleParamWarning {
2615 ParmVarDecl *OldParm;
2616 ParmVarDecl *NewParm;
2617 QualType PromotedType;
2620 } // end anonymous namespace
2622 /// getSpecialMember - get the special member enum for a method.
2623 Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) {
2624 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
2625 if (Ctor->isDefaultConstructor())
2626 return Sema::CXXDefaultConstructor;
2628 if (Ctor->isCopyConstructor())
2629 return Sema::CXXCopyConstructor;
2631 if (Ctor->isMoveConstructor())
2632 return Sema::CXXMoveConstructor;
2633 } else if (isa<CXXDestructorDecl>(MD)) {
2634 return Sema::CXXDestructor;
2635 } else if (MD->isCopyAssignmentOperator()) {
2636 return Sema::CXXCopyAssignment;
2637 } else if (MD->isMoveAssignmentOperator()) {
2638 return Sema::CXXMoveAssignment;
2641 return Sema::CXXInvalid;
2644 // Determine whether the previous declaration was a definition, implicit
2645 // declaration, or a declaration.
2646 template <typename T>
2647 static std::pair<diag::kind, SourceLocation>
2648 getNoteDiagForInvalidRedeclaration(const T *Old, const T *New) {
2649 diag::kind PrevDiag;
2650 SourceLocation OldLocation = Old->getLocation();
2651 if (Old->isThisDeclarationADefinition())
2652 PrevDiag = diag::note_previous_definition;
2653 else if (Old->isImplicit()) {
2654 PrevDiag = diag::note_previous_implicit_declaration;
2655 if (OldLocation.isInvalid())
2656 OldLocation = New->getLocation();
2658 PrevDiag = diag::note_previous_declaration;
2659 return std::make_pair(PrevDiag, OldLocation);
2662 /// canRedefineFunction - checks if a function can be redefined. Currently,
2663 /// only extern inline functions can be redefined, and even then only in
2665 static bool canRedefineFunction(const FunctionDecl *FD,
2666 const LangOptions& LangOpts) {
2667 return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) &&
2668 !LangOpts.CPlusPlus &&
2669 FD->isInlineSpecified() &&
2670 FD->getStorageClass() == SC_Extern);
2673 const AttributedType *Sema::getCallingConvAttributedType(QualType T) const {
2674 const AttributedType *AT = T->getAs<AttributedType>();
2675 while (AT && !AT->isCallingConv())
2676 AT = AT->getModifiedType()->getAs<AttributedType>();
2680 template <typename T>
2681 static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) {
2682 const DeclContext *DC = Old->getDeclContext();
2686 LanguageLinkage OldLinkage = Old->getLanguageLinkage();
2687 if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext())
2689 if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext())
2694 template<typename T> static bool isExternC(T *D) { return D->isExternC(); }
2695 static bool isExternC(VarTemplateDecl *) { return false; }
2697 /// \brief Check whether a redeclaration of an entity introduced by a
2698 /// using-declaration is valid, given that we know it's not an overload
2699 /// (nor a hidden tag declaration).
2700 template<typename ExpectedDecl>
2701 static bool checkUsingShadowRedecl(Sema &S, UsingShadowDecl *OldS,
2702 ExpectedDecl *New) {
2703 // C++11 [basic.scope.declarative]p4:
2704 // Given a set of declarations in a single declarative region, each of
2705 // which specifies the same unqualified name,
2706 // -- they shall all refer to the same entity, or all refer to functions
2707 // and function templates; or
2708 // -- exactly one declaration shall declare a class name or enumeration
2709 // name that is not a typedef name and the other declarations shall all
2710 // refer to the same variable or enumerator, or all refer to functions
2711 // and function templates; in this case the class name or enumeration
2712 // name is hidden (3.3.10).
2714 // C++11 [namespace.udecl]p14:
2715 // If a function declaration in namespace scope or block scope has the
2716 // same name and the same parameter-type-list as a function introduced
2717 // by a using-declaration, and the declarations do not declare the same
2718 // function, the program is ill-formed.
2720 auto *Old = dyn_cast<ExpectedDecl>(OldS->getTargetDecl());
2722 !Old->getDeclContext()->getRedeclContext()->Equals(
2723 New->getDeclContext()->getRedeclContext()) &&
2724 !(isExternC(Old) && isExternC(New)))
2728 S.Diag(New->getLocation(), diag::err_using_decl_conflict_reverse);
2729 S.Diag(OldS->getTargetDecl()->getLocation(), diag::note_using_decl_target);
2730 S.Diag(OldS->getUsingDecl()->getLocation(), diag::note_using_decl) << 0;
2736 static bool hasIdenticalPassObjectSizeAttrs(const FunctionDecl *A,
2737 const FunctionDecl *B) {
2738 assert(A->getNumParams() == B->getNumParams());
2740 auto AttrEq = [](const ParmVarDecl *A, const ParmVarDecl *B) {
2741 const auto *AttrA = A->getAttr<PassObjectSizeAttr>();
2742 const auto *AttrB = B->getAttr<PassObjectSizeAttr>();
2745 return AttrA && AttrB && AttrA->getType() == AttrB->getType();
2748 return std::equal(A->param_begin(), A->param_end(), B->param_begin(), AttrEq);
2751 /// MergeFunctionDecl - We just parsed a function 'New' from
2752 /// declarator D which has the same name and scope as a previous
2753 /// declaration 'Old'. Figure out how to resolve this situation,
2754 /// merging decls or emitting diagnostics as appropriate.
2756 /// In C++, New and Old must be declarations that are not
2757 /// overloaded. Use IsOverload to determine whether New and Old are
2758 /// overloaded, and to select the Old declaration that New should be
2761 /// Returns true if there was an error, false otherwise.
2762 bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
2763 Scope *S, bool MergeTypeWithOld) {
2764 // Verify the old decl was also a function.
2765 FunctionDecl *Old = OldD->getAsFunction();
2767 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) {
2768 if (New->getFriendObjectKind()) {
2769 Diag(New->getLocation(), diag::err_using_decl_friend);
2770 Diag(Shadow->getTargetDecl()->getLocation(),
2771 diag::note_using_decl_target);
2772 Diag(Shadow->getUsingDecl()->getLocation(),
2773 diag::note_using_decl) << 0;
2777 // Check whether the two declarations might declare the same function.
2778 if (checkUsingShadowRedecl<FunctionDecl>(*this, Shadow, New))
2780 OldD = Old = cast<FunctionDecl>(Shadow->getTargetDecl());
2782 Diag(New->getLocation(), diag::err_redefinition_different_kind)
2783 << New->getDeclName();
2784 Diag(OldD->getLocation(), diag::note_previous_definition);
2789 // If the old declaration is invalid, just give up here.
2790 if (Old->isInvalidDecl())
2793 diag::kind PrevDiag;
2794 SourceLocation OldLocation;
2795 std::tie(PrevDiag, OldLocation) =
2796 getNoteDiagForInvalidRedeclaration(Old, New);
2798 // Don't complain about this if we're in GNU89 mode and the old function
2799 // is an extern inline function.
2800 // Don't complain about specializations. They are not supposed to have
2802 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) &&
2803 New->getStorageClass() == SC_Static &&
2804 Old->hasExternalFormalLinkage() &&
2805 !New->getTemplateSpecializationInfo() &&
2806 !canRedefineFunction(Old, getLangOpts())) {
2807 if (getLangOpts().MicrosoftExt) {
2808 Diag(New->getLocation(), diag::ext_static_non_static) << New;
2809 Diag(OldLocation, PrevDiag);
2811 Diag(New->getLocation(), diag::err_static_non_static) << New;
2812 Diag(OldLocation, PrevDiag);
2817 if (New->hasAttr<InternalLinkageAttr>() &&
2818 !Old->hasAttr<InternalLinkageAttr>()) {
2819 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
2820 << New->getDeclName();
2821 Diag(Old->getLocation(), diag::note_previous_definition);
2822 New->dropAttr<InternalLinkageAttr>();
2825 // If a function is first declared with a calling convention, but is later
2826 // declared or defined without one, all following decls assume the calling
2827 // convention of the first.
2829 // It's OK if a function is first declared without a calling convention,
2830 // but is later declared or defined with the default calling convention.
2832 // To test if either decl has an explicit calling convention, we look for
2833 // AttributedType sugar nodes on the type as written. If they are missing or
2834 // were canonicalized away, we assume the calling convention was implicit.
2836 // Note also that we DO NOT return at this point, because we still have
2837 // other tests to run.
2838 QualType OldQType = Context.getCanonicalType(Old->getType());
2839 QualType NewQType = Context.getCanonicalType(New->getType());
2840 const FunctionType *OldType = cast<FunctionType>(OldQType);
2841 const FunctionType *NewType = cast<FunctionType>(NewQType);
2842 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo();
2843 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo();
2844 bool RequiresAdjustment = false;
2846 if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) {
2847 FunctionDecl *First = Old->getFirstDecl();
2848 const FunctionType *FT =
2849 First->getType().getCanonicalType()->castAs<FunctionType>();
2850 FunctionType::ExtInfo FI = FT->getExtInfo();
2851 bool NewCCExplicit = getCallingConvAttributedType(New->getType());
2852 if (!NewCCExplicit) {
2853 // Inherit the CC from the previous declaration if it was specified
2854 // there but not here.
2855 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
2856 RequiresAdjustment = true;
2858 // Calling conventions aren't compatible, so complain.
2859 bool FirstCCExplicit = getCallingConvAttributedType(First->getType());
2860 Diag(New->getLocation(), diag::err_cconv_change)
2861 << FunctionType::getNameForCallConv(NewTypeInfo.getCC())
2863 << (!FirstCCExplicit ? "" :
2864 FunctionType::getNameForCallConv(FI.getCC()));
2866 // Put the note on the first decl, since it is the one that matters.
2867 Diag(First->getLocation(), diag::note_previous_declaration);
2872 // FIXME: diagnose the other way around?
2873 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) {
2874 NewTypeInfo = NewTypeInfo.withNoReturn(true);
2875 RequiresAdjustment = true;
2878 // Merge regparm attribute.
2879 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() ||
2880 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) {
2881 if (NewTypeInfo.getHasRegParm()) {
2882 Diag(New->getLocation(), diag::err_regparm_mismatch)
2883 << NewType->getRegParmType()
2884 << OldType->getRegParmType();
2885 Diag(OldLocation, diag::note_previous_declaration);
2889 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm());
2890 RequiresAdjustment = true;
2893 // Merge ns_returns_retained attribute.
2894 if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) {
2895 if (NewTypeInfo.getProducesResult()) {
2896 Diag(New->getLocation(), diag::err_returns_retained_mismatch);
2897 Diag(OldLocation, diag::note_previous_declaration);
2901 NewTypeInfo = NewTypeInfo.withProducesResult(true);
2902 RequiresAdjustment = true;
2905 if (RequiresAdjustment) {
2906 const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>();
2907 AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo);
2908 New->setType(QualType(AdjustedType, 0));
2909 NewQType = Context.getCanonicalType(New->getType());
2910 NewType = cast<FunctionType>(NewQType);
2913 // If this redeclaration makes the function inline, we may need to add it to
2914 // UndefinedButUsed.
2915 if (!Old->isInlined() && New->isInlined() &&
2916 !New->hasAttr<GNUInlineAttr>() &&
2917 !getLangOpts().GNUInline &&
2918 Old->isUsed(false) &&
2919 !Old->isDefined() && !New->isThisDeclarationADefinition())
2920 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
2923 // If this redeclaration makes it newly gnu_inline, we don't want to warn
2925 if (New->hasAttr<GNUInlineAttr>() &&
2926 Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) {
2927 UndefinedButUsed.erase(Old->getCanonicalDecl());
2930 // If pass_object_size params don't match up perfectly, this isn't a valid
2932 if (Old->getNumParams() > 0 && Old->getNumParams() == New->getNumParams() &&
2933 !hasIdenticalPassObjectSizeAttrs(Old, New)) {
2934 Diag(New->getLocation(), diag::err_different_pass_object_size_params)
2935 << New->getDeclName();
2936 Diag(OldLocation, PrevDiag) << Old << Old->getType();
2940 if (getLangOpts().CPlusPlus) {
2941 // C++1z [over.load]p2
2942 // Certain function declarations cannot be overloaded:
2943 // -- Function declarations that differ only in the return type,
2944 // the exception specification, or both cannot be overloaded.
2946 // Check the exception specifications match. This may recompute the type of
2947 // both Old and New if it resolved exception specifications, so grab the
2948 // types again after this. Because this updates the type, we do this before
2949 // any of the other checks below, which may update the "de facto" NewQType
2950 // but do not necessarily update the type of New.
2951 if (CheckEquivalentExceptionSpec(Old, New))
2953 OldQType = Context.getCanonicalType(Old->getType());
2954 NewQType = Context.getCanonicalType(New->getType());
2956 // Go back to the type source info to compare the declared return types,
2957 // per C++1y [dcl.type.auto]p13:
2958 // Redeclarations or specializations of a function or function template
2959 // with a declared return type that uses a placeholder type shall also
2960 // use that placeholder, not a deduced type.
2961 QualType OldDeclaredReturnType =
2962 (Old->getTypeSourceInfo()
2963 ? Old->getTypeSourceInfo()->getType()->castAs<FunctionType>()
2964 : OldType)->getReturnType();
2965 QualType NewDeclaredReturnType =
2966 (New->getTypeSourceInfo()
2967 ? New->getTypeSourceInfo()->getType()->castAs<FunctionType>()
2968 : NewType)->getReturnType();
2969 if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType) &&
2970 !((NewQType->isDependentType() || OldQType->isDependentType()) &&
2971 New->isLocalExternDecl())) {
2973 if (NewDeclaredReturnType->isObjCObjectPointerType() &&
2974 OldDeclaredReturnType->isObjCObjectPointerType())
2975 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType);
2976 if (ResQT.isNull()) {
2977 if (New->isCXXClassMember() && New->isOutOfLine())
2978 Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type)
2979 << New << New->getReturnTypeSourceRange();
2981 Diag(New->getLocation(), diag::err_ovl_diff_return_type)
2982 << New->getReturnTypeSourceRange();
2983 Diag(OldLocation, PrevDiag) << Old << Old->getType()
2984 << Old->getReturnTypeSourceRange();
2991 QualType OldReturnType = OldType->getReturnType();
2992 QualType NewReturnType = cast<FunctionType>(NewQType)->getReturnType();
2993 if (OldReturnType != NewReturnType) {
2994 // If this function has a deduced return type and has already been
2995 // defined, copy the deduced value from the old declaration.
2996 AutoType *OldAT = Old->getReturnType()->getContainedAutoType();
2997 if (OldAT && OldAT->isDeduced()) {
2999 SubstAutoType(New->getType(),
3000 OldAT->isDependentType() ? Context.DependentTy
3001 : OldAT->getDeducedType()));
3002 NewQType = Context.getCanonicalType(
3003 SubstAutoType(NewQType,
3004 OldAT->isDependentType() ? Context.DependentTy
3005 : OldAT->getDeducedType()));
3009 const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
3010 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
3011 if (OldMethod && NewMethod) {
3012 // Preserve triviality.
3013 NewMethod->setTrivial(OldMethod->isTrivial());
3015 // MSVC allows explicit template specialization at class scope:
3016 // 2 CXXMethodDecls referring to the same function will be injected.
3017 // We don't want a redeclaration error.
3018 bool IsClassScopeExplicitSpecialization =
3019 OldMethod->isFunctionTemplateSpecialization() &&
3020 NewMethod->isFunctionTemplateSpecialization();
3021 bool isFriend = NewMethod->getFriendObjectKind();
3023 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() &&
3024 !IsClassScopeExplicitSpecialization) {
3025 // -- Member function declarations with the same name and the
3026 // same parameter types cannot be overloaded if any of them
3027 // is a static member function declaration.
3028 if (OldMethod->isStatic() != NewMethod->isStatic()) {
3029 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
3030 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3034 // C++ [class.mem]p1:
3035 // [...] A member shall not be declared twice in the
3036 // member-specification, except that a nested class or member
3037 // class template can be declared and then later defined.
3038 if (ActiveTemplateInstantiations.empty()) {
3040 if (isa<CXXConstructorDecl>(OldMethod))
3041 NewDiag = diag::err_constructor_redeclared;
3042 else if (isa<CXXDestructorDecl>(NewMethod))
3043 NewDiag = diag::err_destructor_redeclared;
3044 else if (isa<CXXConversionDecl>(NewMethod))
3045 NewDiag = diag::err_conv_function_redeclared;
3047 NewDiag = diag::err_member_redeclared;
3049 Diag(New->getLocation(), NewDiag);
3051 Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation)
3052 << New << New->getType();
3054 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3057 // Complain if this is an explicit declaration of a special
3058 // member that was initially declared implicitly.
3060 // As an exception, it's okay to befriend such methods in order
3061 // to permit the implicit constructor/destructor/operator calls.
3062 } else if (OldMethod->isImplicit()) {
3064 NewMethod->setImplicit();
3066 Diag(NewMethod->getLocation(),
3067 diag::err_definition_of_implicitly_declared_member)
3068 << New << getSpecialMember(OldMethod);
3071 } else if (OldMethod->getFirstDecl()->isExplicitlyDefaulted() && !isFriend) {
3072 Diag(NewMethod->getLocation(),
3073 diag::err_definition_of_explicitly_defaulted_member)
3074 << getSpecialMember(OldMethod);
3079 // C++11 [dcl.attr.noreturn]p1:
3080 // The first declaration of a function shall specify the noreturn
3081 // attribute if any declaration of that function specifies the noreturn
3083 const CXX11NoReturnAttr *NRA = New->getAttr<CXX11NoReturnAttr>();
3084 if (NRA && !Old->hasAttr<CXX11NoReturnAttr>()) {
3085 Diag(NRA->getLocation(), diag::err_noreturn_missing_on_first_decl);
3086 Diag(Old->getFirstDecl()->getLocation(),
3087 diag::note_noreturn_missing_first_decl);
3090 // C++11 [dcl.attr.depend]p2:
3091 // The first declaration of a function shall specify the
3092 // carries_dependency attribute for its declarator-id if any declaration
3093 // of the function specifies the carries_dependency attribute.
3094 const CarriesDependencyAttr *CDA = New->getAttr<CarriesDependencyAttr>();
3095 if (CDA && !Old->hasAttr<CarriesDependencyAttr>()) {
3096 Diag(CDA->getLocation(),
3097 diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/;
3098 Diag(Old->getFirstDecl()->getLocation(),
3099 diag::note_carries_dependency_missing_first_decl) << 0/*Function*/;
3103 // All declarations for a function shall agree exactly in both the
3104 // return type and the parameter-type-list.
3105 // We also want to respect all the extended bits except noreturn.
3107 // noreturn should now match unless the old type info didn't have it.
3108 QualType OldQTypeForComparison = OldQType;
3109 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) {
3110 auto *OldType = OldQType->castAs<FunctionProtoType>();
3111 const FunctionType *OldTypeForComparison
3112 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true));
3113 OldQTypeForComparison = QualType(OldTypeForComparison, 0);
3114 assert(OldQTypeForComparison.isCanonical());
3117 if (haveIncompatibleLanguageLinkages(Old, New)) {
3118 // As a special case, retain the language linkage from previous
3119 // declarations of a friend function as an extension.
3121 // This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC
3122 // and is useful because there's otherwise no way to specify language
3123 // linkage within class scope.
3125 // Check cautiously as the friend object kind isn't yet complete.
3126 if (New->getFriendObjectKind() != Decl::FOK_None) {
3127 Diag(New->getLocation(), diag::ext_retained_language_linkage) << New;
3128 Diag(OldLocation, PrevDiag);
3130 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3131 Diag(OldLocation, PrevDiag);
3136 if (OldQTypeForComparison == NewQType)
3137 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3139 if ((NewQType->isDependentType() || OldQType->isDependentType()) &&
3140 New->isLocalExternDecl()) {
3141 // It's OK if we couldn't merge types for a local function declaraton
3142 // if either the old or new type is dependent. We'll merge the types
3143 // when we instantiate the function.
3147 // Fall through for conflicting redeclarations and redefinitions.
3150 // C: Function types need to be compatible, not identical. This handles
3151 // duplicate function decls like "void f(int); void f(enum X);" properly.
3152 if (!getLangOpts().CPlusPlus &&
3153 Context.typesAreCompatible(OldQType, NewQType)) {
3154 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>();
3155 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>();
3156 const FunctionProtoType *OldProto = nullptr;
3157 if (MergeTypeWithOld && isa<FunctionNoProtoType>(NewFuncType) &&
3158 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) {
3159 // The old declaration provided a function prototype, but the
3160 // new declaration does not. Merge in the prototype.
3161 assert(!OldProto->hasExceptionSpec() && "Exception spec in C");
3162 SmallVector<QualType, 16> ParamTypes(OldProto->param_types());
3164 Context.getFunctionType(NewFuncType->getReturnType(), ParamTypes,
3165 OldProto->getExtProtoInfo());
3166 New->setType(NewQType);
3167 New->setHasInheritedPrototype();
3169 // Synthesize parameters with the same types.
3170 SmallVector<ParmVarDecl*, 16> Params;
3171 for (const auto &ParamType : OldProto->param_types()) {
3172 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(),
3173 SourceLocation(), nullptr,
3174 ParamType, /*TInfo=*/nullptr,
3176 Param->setScopeInfo(0, Params.size());
3177 Param->setImplicit();
3178 Params.push_back(Param);
3181 New->setParams(Params);
3184 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3187 // GNU C permits a K&R definition to follow a prototype declaration
3188 // if the declared types of the parameters in the K&R definition
3189 // match the types in the prototype declaration, even when the
3190 // promoted types of the parameters from the K&R definition differ
3191 // from the types in the prototype. GCC then keeps the types from
3194 // If a variadic prototype is followed by a non-variadic K&R definition,
3195 // the K&R definition becomes variadic. This is sort of an edge case, but
3196 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and
3198 if (!getLangOpts().CPlusPlus &&
3199 Old->hasPrototype() && !New->hasPrototype() &&
3200 New->getType()->getAs<FunctionProtoType>() &&
3201 Old->getNumParams() == New->getNumParams()) {
3202 SmallVector<QualType, 16> ArgTypes;
3203 SmallVector<GNUCompatibleParamWarning, 16> Warnings;
3204 const FunctionProtoType *OldProto
3205 = Old->getType()->getAs<FunctionProtoType>();
3206 const FunctionProtoType *NewProto
3207 = New->getType()->getAs<FunctionProtoType>();
3209 // Determine whether this is the GNU C extension.
3210 QualType MergedReturn = Context.mergeTypes(OldProto->getReturnType(),
3211 NewProto->getReturnType());
3212 bool LooseCompatible = !MergedReturn.isNull();
3213 for (unsigned Idx = 0, End = Old->getNumParams();
3214 LooseCompatible && Idx != End; ++Idx) {
3215 ParmVarDecl *OldParm = Old->getParamDecl(Idx);
3216 ParmVarDecl *NewParm = New->getParamDecl(Idx);
3217 if (Context.typesAreCompatible(OldParm->getType(),
3218 NewProto->getParamType(Idx))) {
3219 ArgTypes.push_back(NewParm->getType());
3220 } else if (Context.typesAreCompatible(OldParm->getType(),
3222 /*CompareUnqualified=*/true)) {
3223 GNUCompatibleParamWarning Warn = { OldParm, NewParm,
3224 NewProto->getParamType(Idx) };
3225 Warnings.push_back(Warn);
3226 ArgTypes.push_back(NewParm->getType());
3228 LooseCompatible = false;
3231 if (LooseCompatible) {
3232 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) {
3233 Diag(Warnings[Warn].NewParm->getLocation(),
3234 diag::ext_param_promoted_not_compatible_with_prototype)
3235 << Warnings[Warn].PromotedType
3236 << Warnings[Warn].OldParm->getType();
3237 if (Warnings[Warn].OldParm->getLocation().isValid())
3238 Diag(Warnings[Warn].OldParm->getLocation(),
3239 diag::note_previous_declaration);
3242 if (MergeTypeWithOld)
3243 New->setType(Context.getFunctionType(MergedReturn, ArgTypes,
3244 OldProto->getExtProtoInfo()));
3245 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
3248 // Fall through to diagnose conflicting types.
3251 // A function that has already been declared has been redeclared or
3252 // defined with a different type; show an appropriate diagnostic.
3254 // If the previous declaration was an implicitly-generated builtin
3255 // declaration, then at the very least we should use a specialized note.
3257 if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) {
3258 // If it's actually a library-defined builtin function like 'malloc'
3259 // or 'printf', just warn about the incompatible redeclaration.
3260 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) {
3261 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New;
3262 Diag(OldLocation, diag::note_previous_builtin_declaration)
3263 << Old << Old->getType();
3265 // If this is a global redeclaration, just forget hereafter
3266 // about the "builtin-ness" of the function.
3268 // Doing this for local extern declarations is problematic. If
3269 // the builtin declaration remains visible, a second invalid
3270 // local declaration will produce a hard error; if it doesn't
3271 // remain visible, a single bogus local redeclaration (which is
3272 // actually only a warning) could break all the downstream code.
3273 if (!New->getLexicalDeclContext()->isFunctionOrMethod())
3274 New->getIdentifier()->revertBuiltin();
3279 PrevDiag = diag::note_previous_builtin_declaration;
3282 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName();
3283 Diag(OldLocation, PrevDiag) << Old << Old->getType();
3287 /// \brief Completes the merge of two function declarations that are
3288 /// known to be compatible.
3290 /// This routine handles the merging of attributes and other
3291 /// properties of function declarations from the old declaration to
3292 /// the new declaration, once we know that New is in fact a
3293 /// redeclaration of Old.
3296 bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
3297 Scope *S, bool MergeTypeWithOld) {
3298 // Merge the attributes
3299 mergeDeclAttributes(New, Old);
3301 // Merge "pure" flag.
3305 // Merge "used" flag.
3306 if (Old->getMostRecentDecl()->isUsed(false))
3309 // Merge attributes from the parameters. These can mismatch with K&R
3311 if (New->getNumParams() == Old->getNumParams())
3312 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) {
3313 ParmVarDecl *NewParam = New->getParamDecl(i);
3314 ParmVarDecl *OldParam = Old->getParamDecl(i);
3315 mergeParamDeclAttributes(NewParam, OldParam, *this);
3316 mergeParamDeclTypes(NewParam, OldParam, *this);
3319 if (getLangOpts().CPlusPlus)
3320 return MergeCXXFunctionDecl(New, Old, S);
3322 // Merge the function types so the we get the composite types for the return
3323 // and argument types. Per C11 6.2.7/4, only update the type if the old decl
3325 QualType Merged = Context.mergeTypes(Old->getType(), New->getType());
3326 if (!Merged.isNull() && MergeTypeWithOld)
3327 New->setType(Merged);
3332 void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod,
3333 ObjCMethodDecl *oldMethod) {
3334 // Merge the attributes, including deprecated/unavailable
3335 AvailabilityMergeKind MergeKind =
3336 isa<ObjCProtocolDecl>(oldMethod->getDeclContext())
3337 ? AMK_ProtocolImplementation
3338 : isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration
3341 mergeDeclAttributes(newMethod, oldMethod, MergeKind);
3343 // Merge attributes from the parameters.
3344 ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(),
3345 oe = oldMethod->param_end();
3346 for (ObjCMethodDecl::param_iterator
3347 ni = newMethod->param_begin(), ne = newMethod->param_end();
3348 ni != ne && oi != oe; ++ni, ++oi)
3349 mergeParamDeclAttributes(*ni, *oi, *this);
3351 CheckObjCMethodOverride(newMethod, oldMethod);
3354 static void diagnoseVarDeclTypeMismatch(Sema &S, VarDecl *New, VarDecl* Old) {
3355 assert(!S.Context.hasSameType(New->getType(), Old->getType()));
3357 S.Diag(New->getLocation(), New->isThisDeclarationADefinition()
3358 ? diag::err_redefinition_different_type
3359 : diag::err_redeclaration_different_type)
3360 << New->getDeclName() << New->getType() << Old->getType();
3362 diag::kind PrevDiag;
3363 SourceLocation OldLocation;
3364 std::tie(PrevDiag, OldLocation)
3365 = getNoteDiagForInvalidRedeclaration(Old, New);
3366 S.Diag(OldLocation, PrevDiag);
3367 New->setInvalidDecl();
3370 /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and
3371 /// scope as a previous declaration 'Old'. Figure out how to merge their types,
3372 /// emitting diagnostics as appropriate.
3374 /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back
3375 /// to here in AddInitializerToDecl. We can't check them before the initializer
3377 void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old,
3378 bool MergeTypeWithOld) {
3379 if (New->isInvalidDecl() || Old->isInvalidDecl())
3383 if (getLangOpts().CPlusPlus) {
3384 if (New->getType()->isUndeducedType()) {
3385 // We don't know what the new type is until the initializer is attached.
3387 } else if (Context.hasSameType(New->getType(), Old->getType())) {
3388 // These could still be something that needs exception specs checked.
3389 return MergeVarDeclExceptionSpecs(New, Old);
3391 // C++ [basic.link]p10:
3392 // [...] the types specified by all declarations referring to a given
3393 // object or function shall be identical, except that declarations for an
3394 // array object can specify array types that differ by the presence or
3395 // absence of a major array bound (8.3.4).
3396 else if (Old->getType()->isArrayType() && New->getType()->isArrayType()) {
3397 const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
3398 const ArrayType *NewArray = Context.getAsArrayType(New->getType());
3400 // We are merging a variable declaration New into Old. If it has an array
3401 // bound, and that bound differs from Old's bound, we should diagnose the
3403 if (!NewArray->isIncompleteArrayType() && !NewArray->isDependentType()) {
3404 for (VarDecl *PrevVD = Old->getMostRecentDecl(); PrevVD;
3405 PrevVD = PrevVD->getPreviousDecl()) {
3406 const ArrayType *PrevVDTy = Context.getAsArrayType(PrevVD->getType());
3407 if (PrevVDTy->isIncompleteArrayType() || PrevVDTy->isDependentType())
3410 if (!Context.hasSameType(NewArray, PrevVDTy))
3411 return diagnoseVarDeclTypeMismatch(*this, New, PrevVD);
3415 if (OldArray->isIncompleteArrayType() && NewArray->isArrayType()) {
3416 if (Context.hasSameType(OldArray->getElementType(),
3417 NewArray->getElementType()))
3418 MergedT = New->getType();
3420 // FIXME: Check visibility. New is hidden but has a complete type. If New
3421 // has no array bound, it should not inherit one from Old, if Old is not
3423 else if (OldArray->isArrayType() && NewArray->isIncompleteArrayType()) {
3424 if (Context.hasSameType(OldArray->getElementType(),
3425 NewArray->getElementType()))
3426 MergedT = Old->getType();
3429 else if (New->getType()->isObjCObjectPointerType() &&
3430 Old->getType()->isObjCObjectPointerType()) {
3431 MergedT = Context.mergeObjCGCQualifiers(New->getType(),
3436 // All declarations that refer to the same object or function shall have
3438 MergedT = Context.mergeTypes(New->getType(), Old->getType());
3440 if (MergedT.isNull()) {
3441 // It's OK if we couldn't merge types if either type is dependent, for a
3442 // block-scope variable. In other cases (static data members of class
3443 // templates, variable templates, ...), we require the types to be
3445 // FIXME: The C++ standard doesn't say anything about this.
3446 if ((New->getType()->isDependentType() ||
3447 Old->getType()->isDependentType()) && New->isLocalVarDecl()) {
3448 // If the old type was dependent, we can't merge with it, so the new type
3449 // becomes dependent for now. We'll reproduce the original type when we
3450 // instantiate the TypeSourceInfo for the variable.
3451 if (!New->getType()->isDependentType() && MergeTypeWithOld)
3452 New->setType(Context.DependentTy);
3455 return diagnoseVarDeclTypeMismatch(*this, New, Old);
3458 // Don't actually update the type on the new declaration if the old
3459 // declaration was an extern declaration in a different scope.
3460 if (MergeTypeWithOld)
3461 New->setType(MergedT);
3464 static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD,
3465 LookupResult &Previous) {
3467 // For an identifier with internal or external linkage declared
3468 // in a scope in which a prior declaration of that identifier is
3469 // visible, if the prior declaration specifies internal or
3470 // external linkage, the type of the identifier at the later
3471 // declaration becomes the composite type.
3473 // If the variable isn't visible, we do not merge with its type.
3474 if (Previous.isShadowed())
3477 if (S.getLangOpts().CPlusPlus) {
3478 // C++11 [dcl.array]p3:
3479 // If there is a preceding declaration of the entity in the same
3480 // scope in which the bound was specified, an omitted array bound
3481 // is taken to be the same as in that earlier declaration.
3482 return NewVD->isPreviousDeclInSameBlockScope() ||
3483 (!OldVD->getLexicalDeclContext()->isFunctionOrMethod() &&
3484 !NewVD->getLexicalDeclContext()->isFunctionOrMethod());
3486 // If the old declaration was function-local, don't merge with its
3487 // type unless we're in the same function.
3488 return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() ||
3489 OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext();
3493 /// MergeVarDecl - We just parsed a variable 'New' which has the same name
3494 /// and scope as a previous declaration 'Old'. Figure out how to resolve this
3495 /// situation, merging decls or emitting diagnostics as appropriate.
3497 /// Tentative definition rules (C99 6.9.2p2) are checked by
3498 /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative
3499 /// definitions here, since the initializer hasn't been attached.
3501 void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
3502 // If the new decl is already invalid, don't do any other checking.
3503 if (New->isInvalidDecl())
3506 if (!shouldLinkPossiblyHiddenDecl(Previous, New))
3509 VarTemplateDecl *NewTemplate = New->getDescribedVarTemplate();
3511 // Verify the old decl was also a variable or variable template.
3512 VarDecl *Old = nullptr;
3513 VarTemplateDecl *OldTemplate = nullptr;
3514 if (Previous.isSingleResult()) {
3516 OldTemplate = dyn_cast<VarTemplateDecl>(Previous.getFoundDecl());
3517 Old = OldTemplate ? OldTemplate->getTemplatedDecl() : nullptr;
3520 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3521 if (checkUsingShadowRedecl<VarTemplateDecl>(*this, Shadow, NewTemplate))
3522 return New->setInvalidDecl();
3524 Old = dyn_cast<VarDecl>(Previous.getFoundDecl());
3527 dyn_cast<UsingShadowDecl>(Previous.getRepresentativeDecl()))
3528 if (checkUsingShadowRedecl<VarDecl>(*this, Shadow, New))
3529 return New->setInvalidDecl();
3533 Diag(New->getLocation(), diag::err_redefinition_different_kind)
3534 << New->getDeclName();
3535 Diag(Previous.getRepresentativeDecl()->getLocation(),
3536 diag::note_previous_definition);
3537 return New->setInvalidDecl();
3540 // Ensure the template parameters are compatible.
3542 !TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
3543 OldTemplate->getTemplateParameters(),
3544 /*Complain=*/true, TPL_TemplateMatch))
3545 return New->setInvalidDecl();
3547 // C++ [class.mem]p1:
3548 // A member shall not be declared twice in the member-specification [...]
3550 // Here, we need only consider static data members.
3551 if (Old->isStaticDataMember() && !New->isOutOfLine()) {
3552 Diag(New->getLocation(), diag::err_duplicate_member)
3553 << New->getIdentifier();
3554 Diag(Old->getLocation(), diag::note_previous_declaration);
3555 New->setInvalidDecl();
3558 mergeDeclAttributes(New, Old);
3559 // Warn if an already-declared variable is made a weak_import in a subsequent
3561 if (New->hasAttr<WeakImportAttr>() &&
3562 Old->getStorageClass() == SC_None &&
3563 !Old->hasAttr<WeakImportAttr>()) {
3564 Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName();
3565 Diag(Old->getLocation(), diag::note_previous_definition);
3566 // Remove weak_import attribute on new declaration.
3567 New->dropAttr<WeakImportAttr>();
3570 if (New->hasAttr<InternalLinkageAttr>() &&
3571 !Old->hasAttr<InternalLinkageAttr>()) {
3572 Diag(New->getLocation(), diag::err_internal_linkage_redeclaration)
3573 << New->getDeclName();
3574 Diag(Old->getLocation(), diag::note_previous_definition);
3575 New->dropAttr<InternalLinkageAttr>();
3579 VarDecl *MostRecent = Old->getMostRecentDecl();
3580 if (MostRecent != Old) {
3581 MergeVarDeclTypes(New, MostRecent,
3582 mergeTypeWithPrevious(*this, New, MostRecent, Previous));
3583 if (New->isInvalidDecl())
3587 MergeVarDeclTypes(New, Old, mergeTypeWithPrevious(*this, New, Old, Previous));
3588 if (New->isInvalidDecl())
3591 diag::kind PrevDiag;
3592 SourceLocation OldLocation;
3593 std::tie(PrevDiag, OldLocation) =
3594 getNoteDiagForInvalidRedeclaration(Old, New);
3596 // [dcl.stc]p8: Check if we have a non-static decl followed by a static.
3597 if (New->getStorageClass() == SC_Static &&
3598 !New->isStaticDataMember() &&
3599 Old->hasExternalFormalLinkage()) {
3600 if (getLangOpts().MicrosoftExt) {
3601 Diag(New->getLocation(), diag::ext_static_non_static)
3602 << New->getDeclName();
3603 Diag(OldLocation, PrevDiag);
3605 Diag(New->getLocation(), diag::err_static_non_static)
3606 << New->getDeclName();
3607 Diag(OldLocation, PrevDiag);
3608 return New->setInvalidDecl();
3612 // For an identifier declared with the storage-class specifier
3613 // extern in a scope in which a prior declaration of that
3614 // identifier is visible,23) if the prior declaration specifies
3615 // internal or external linkage, the linkage of the identifier at
3616 // the later declaration is the same as the linkage specified at
3617 // the prior declaration. If no prior declaration is visible, or
3618 // if the prior declaration specifies no linkage, then the
3619 // identifier has external linkage.
3620 if (New->hasExternalStorage() && Old->hasLinkage())
3622 else if (New->getCanonicalDecl()->getStorageClass() != SC_Static &&
3623 !New->isStaticDataMember() &&
3624 Old->getCanonicalDecl()->getStorageClass() == SC_Static) {
3625 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName();
3626 Diag(OldLocation, PrevDiag);
3627 return New->setInvalidDecl();
3630 // Check if extern is followed by non-extern and vice-versa.
3631 if (New->hasExternalStorage() &&
3632 !Old->hasLinkage() && Old->isLocalVarDeclOrParm()) {
3633 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName();
3634 Diag(OldLocation, PrevDiag);
3635 return New->setInvalidDecl();
3637 if (Old->hasLinkage() && New->isLocalVarDeclOrParm() &&
3638 !New->hasExternalStorage()) {
3639 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName();
3640 Diag(OldLocation, PrevDiag);
3641 return New->setInvalidDecl();
3644 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup.
3646 // FIXME: The test for external storage here seems wrong? We still
3647 // need to check for mismatches.
3648 if (!New->hasExternalStorage() && !New->isFileVarDecl() &&
3649 // Don't complain about out-of-line definitions of static members.
3650 !(Old->getLexicalDeclContext()->isRecord() &&
3651 !New->getLexicalDeclContext()->isRecord())) {
3652 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName();
3653 Diag(OldLocation, PrevDiag);
3654 return New->setInvalidDecl();
3657 if (New->isInline() && !Old->getMostRecentDecl()->isInline()) {
3658 if (VarDecl *Def = Old->getDefinition()) {
3659 // C++1z [dcl.fcn.spec]p4:
3660 // If the definition of a variable appears in a translation unit before
3661 // its first declaration as inline, the program is ill-formed.
3662 Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
3663 Diag(Def->getLocation(), diag::note_previous_definition);
3667 // If this redeclaration makes the function inline, we may need to add it to
3668 // UndefinedButUsed.
3669 if (!Old->isInline() && New->isInline() && Old->isUsed(false) &&
3670 !Old->getDefinition() && !New->isThisDeclarationADefinition())
3671 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
3674 if (New->getTLSKind() != Old->getTLSKind()) {
3675 if (!Old->getTLSKind()) {
3676 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName();
3677 Diag(OldLocation, PrevDiag);
3678 } else if (!New->getTLSKind()) {
3679 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName();
3680 Diag(OldLocation, PrevDiag);
3682 // Do not allow redeclaration to change the variable between requiring
3683 // static and dynamic initialization.
3684 // FIXME: GCC allows this, but uses the TLS keyword on the first
3685 // declaration to determine the kind. Do we need to be compatible here?
3686 Diag(New->getLocation(), diag::err_thread_thread_different_kind)
3687 << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic);
3688 Diag(OldLocation, PrevDiag);
3692 // C++ doesn't have tentative definitions, so go right ahead and check here.
3693 if (getLangOpts().CPlusPlus &&
3694 New->isThisDeclarationADefinition() == VarDecl::Definition) {
3695 if (Old->isStaticDataMember() && Old->getCanonicalDecl()->isInline() &&
3696 Old->getCanonicalDecl()->isConstexpr()) {
3697 // This definition won't be a definition any more once it's been merged.
3698 Diag(New->getLocation(),
3699 diag::warn_deprecated_redundant_constexpr_static_def);
3700 } else if (VarDecl *Def = Old->getDefinition()) {
3701 if (checkVarDeclRedefinition(Def, New))
3706 if (haveIncompatibleLanguageLinkages(Old, New)) {
3707 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3708 Diag(OldLocation, PrevDiag);
3709 New->setInvalidDecl();
3713 // Merge "used" flag.
3714 if (Old->getMostRecentDecl()->isUsed(false))
3717 // Keep a chain of previous declarations.
3718 New->setPreviousDecl(Old);
3720 NewTemplate->setPreviousDecl(OldTemplate);
3722 // Inherit access appropriately.
3723 New->setAccess(Old->getAccess());
3725 NewTemplate->setAccess(New->getAccess());
3727 if (Old->isInline())
3728 New->setImplicitlyInline();
3731 /// We've just determined that \p Old and \p New both appear to be definitions
3732 /// of the same variable. Either diagnose or fix the problem.
3733 bool Sema::checkVarDeclRedefinition(VarDecl *Old, VarDecl *New) {
3734 if (!hasVisibleDefinition(Old) &&
3735 (New->getFormalLinkage() == InternalLinkage ||
3737 New->getDescribedVarTemplate() ||
3738 New->getNumTemplateParameterLists() ||
3739 New->getDeclContext()->isDependentContext())) {
3740 // The previous definition is hidden, and multiple definitions are
3741 // permitted (in separate TUs). Demote this to a declaration.
3742 New->demoteThisDefinitionToDeclaration();
3744 // Make the canonical definition visible.
3745 if (auto *OldTD = Old->getDescribedVarTemplate())
3746 makeMergedDefinitionVisible(OldTD, New->getLocation());
3747 makeMergedDefinitionVisible(Old, New->getLocation());
3750 Diag(New->getLocation(), diag::err_redefinition) << New;
3751 Diag(Old->getLocation(), diag::note_previous_definition);
3752 New->setInvalidDecl();
3757 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3758 /// no declarator (e.g. "struct foo;") is parsed.
3760 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3761 RecordDecl *&AnonRecord) {
3762 return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg(), false,
3766 // The MS ABI changed between VS2013 and VS2015 with regard to numbers used to
3767 // disambiguate entities defined in different scopes.
3768 // While the VS2015 ABI fixes potential miscompiles, it is also breaks
3770 // We will pick our mangling number depending on which version of MSVC is being
3772 static unsigned getMSManglingNumber(const LangOptions &LO, Scope *S) {
3773 return LO.isCompatibleWithMSVC(LangOptions::MSVC2015)
3774 ? S->getMSCurManglingNumber()
3775 : S->getMSLastManglingNumber();
3778 void Sema::handleTagNumbering(const TagDecl *Tag, Scope *TagScope) {
3779 if (!Context.getLangOpts().CPlusPlus)
3782 if (isa<CXXRecordDecl>(Tag->getParent())) {
3783 // If this tag is the direct child of a class, number it if
3785 if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl())
3787 MangleNumberingContext &MCtx =
3788 Context.getManglingNumberContext(Tag->getParent());
3789 Context.setManglingNumber(
3790 Tag, MCtx.getManglingNumber(
3791 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3795 // If this tag isn't a direct child of a class, number it if it is local.
3796 Decl *ManglingContextDecl;
3797 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
3798 Tag->getDeclContext(), ManglingContextDecl)) {
3799 Context.setManglingNumber(
3800 Tag, MCtx->getManglingNumber(
3801 Tag, getMSManglingNumber(getLangOpts(), TagScope)));
3805 void Sema::setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,
3806 TypedefNameDecl *NewTD) {
3807 if (TagFromDeclSpec->isInvalidDecl())
3810 // Do nothing if the tag already has a name for linkage purposes.
3811 if (TagFromDeclSpec->hasNameForLinkage())
3814 // A well-formed anonymous tag must always be a TUK_Definition.
3815 assert(TagFromDeclSpec->isThisDeclarationADefinition());
3817 // The type must match the tag exactly; no qualifiers allowed.
3818 if (!Context.hasSameType(NewTD->getUnderlyingType(),
3819 Context.getTagDeclType(TagFromDeclSpec))) {
3820 if (getLangOpts().CPlusPlus)
3821 Context.addTypedefNameForUnnamedTagDecl(TagFromDeclSpec, NewTD);
3825 // If we've already computed linkage for the anonymous tag, then
3826 // adding a typedef name for the anonymous decl can change that
3827 // linkage, which might be a serious problem. Diagnose this as
3828 // unsupported and ignore the typedef name. TODO: we should
3829 // pursue this as a language defect and establish a formal rule
3830 // for how to handle it.
3831 if (TagFromDeclSpec->hasLinkageBeenComputed()) {
3832 Diag(NewTD->getLocation(), diag::err_typedef_changes_linkage);
3834 SourceLocation tagLoc = TagFromDeclSpec->getInnerLocStart();
3835 tagLoc = getLocForEndOfToken(tagLoc);
3837 llvm::SmallString<40> textToInsert;
3838 textToInsert += ' ';
3839 textToInsert += NewTD->getIdentifier()->getName();
3840 Diag(tagLoc, diag::note_typedef_changes_linkage)
3841 << FixItHint::CreateInsertion(tagLoc, textToInsert);
3845 // Otherwise, set this is the anon-decl typedef for the tag.
3846 TagFromDeclSpec->setTypedefNameForAnonDecl(NewTD);
3849 static unsigned GetDiagnosticTypeSpecifierID(DeclSpec::TST T) {
3851 case DeclSpec::TST_class:
3853 case DeclSpec::TST_struct:
3855 case DeclSpec::TST_interface:
3857 case DeclSpec::TST_union:
3859 case DeclSpec::TST_enum:
3862 llvm_unreachable("unexpected type specifier");
3866 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3867 /// no declarator (e.g. "struct foo;") is parsed. It also accepts template
3868 /// parameters to cope with template friend declarations.
3870 Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
3871 MultiTemplateParamsArg TemplateParams,
3872 bool IsExplicitInstantiation,
3873 RecordDecl *&AnonRecord) {
3874 Decl *TagD = nullptr;
3875 TagDecl *Tag = nullptr;
3876 if (DS.getTypeSpecType() == DeclSpec::TST_class ||
3877 DS.getTypeSpecType() == DeclSpec::TST_struct ||
3878 DS.getTypeSpecType() == DeclSpec::TST_interface ||
3879 DS.getTypeSpecType() == DeclSpec::TST_union ||
3880 DS.getTypeSpecType() == DeclSpec::TST_enum) {
3881 TagD = DS.getRepAsDecl();
3883 if (!TagD) // We probably had an error
3886 // Note that the above type specs guarantee that the
3887 // type rep is a Decl, whereas in many of the others
3889 if (isa<TagDecl>(TagD))
3890 Tag = cast<TagDecl>(TagD);
3891 else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD))
3892 Tag = CTD->getTemplatedDecl();
3896 handleTagNumbering(Tag, S);
3897 Tag->setFreeStanding();
3898 if (Tag->isInvalidDecl())
3902 if (unsigned TypeQuals = DS.getTypeQualifiers()) {
3903 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object
3904 // or incomplete types shall not be restrict-qualified."
3905 if (TypeQuals & DeclSpec::TQ_restrict)
3906 Diag(DS.getRestrictSpecLoc(),
3907 diag::err_typecheck_invalid_restrict_not_pointer_noarg)
3908 << DS.getSourceRange();
3911 if (DS.isInlineSpecified())
3912 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
3913 << getLangOpts().CPlusPlus1z;
3915 if (DS.isConstexprSpecified()) {
3916 // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations
3917 // and definitions of functions and variables.
3919 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag)
3920 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType());
3922 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_no_declarators);
3923 // Don't emit warnings after this error.
3927 if (DS.isConceptSpecified()) {
3928 // C++ Concepts TS [dcl.spec.concept]p1: A concept definition refers to
3929 // either a function concept and its definition or a variable concept and
3931 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
3935 DiagnoseFunctionSpecifiers(DS);
3937 if (DS.isFriendSpecified()) {
3938 // If we're dealing with a decl but not a TagDecl, assume that
3939 // whatever routines created it handled the friendship aspect.
3942 return ActOnFriendTypeDecl(S, DS, TemplateParams);
3945 const CXXScopeSpec &SS = DS.getTypeSpecScope();
3946 bool IsExplicitSpecialization =
3947 !TemplateParams.empty() && TemplateParams.back()->size() == 0;
3948 if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() &&
3949 !IsExplicitInstantiation && !IsExplicitSpecialization &&
3950 !isa<ClassTemplatePartialSpecializationDecl>(Tag)) {
3951 // Per C++ [dcl.type.elab]p1, a class declaration cannot have a
3952 // nested-name-specifier unless it is an explicit instantiation
3953 // or an explicit specialization.
3955 // FIXME: We allow class template partial specializations here too, per the
3956 // obvious intent of DR1819.
3958 // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either.
3959 Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier)
3960 << GetDiagnosticTypeSpecifierID(DS.getTypeSpecType()) << SS.getRange();
3964 // Track whether this decl-specifier declares anything.
3965 bool DeclaresAnything = true;
3967 // Handle anonymous struct definitions.
3968 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
3969 if (!Record->getDeclName() && Record->isCompleteDefinition() &&
3970 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) {
3971 if (getLangOpts().CPlusPlus ||
3972 Record->getDeclContext()->isRecord()) {
3973 // If CurContext is a DeclContext that can contain statements,
3974 // RecursiveASTVisitor won't visit the decls that
3975 // BuildAnonymousStructOrUnion() will put into CurContext.
3976 // Also store them here so that they can be part of the
3977 // DeclStmt that gets created in this case.
3978 // FIXME: Also return the IndirectFieldDecls created by
3979 // BuildAnonymousStructOr union, for the same reason?
3980 if (CurContext->isFunctionOrMethod())
3981 AnonRecord = Record;
3982 return BuildAnonymousStructOrUnion(S, DS, AS, Record,
3983 Context.getPrintingPolicy());
3986 DeclaresAnything = false;
3991 // A struct-declaration that does not declare an anonymous structure or
3992 // anonymous union shall contain a struct-declarator-list.
3994 // This rule also existed in C89 and C99; the grammar for struct-declaration
3995 // did not permit a struct-declaration without a struct-declarator-list.
3996 if (!getLangOpts().CPlusPlus && CurContext->isRecord() &&
3997 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) {
3998 // Check for Microsoft C extension: anonymous struct/union member.
3999 // Handle 2 kinds of anonymous struct/union:
4003 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct.
4004 // UNION_TYPE; <- where UNION_TYPE is a typedef union.
4005 if ((Tag && Tag->getDeclName()) ||
4006 DS.getTypeSpecType() == DeclSpec::TST_typename) {
4007 RecordDecl *Record = nullptr;
4009 Record = dyn_cast<RecordDecl>(Tag);
4010 else if (const RecordType *RT =
4011 DS.getRepAsType().get()->getAsStructureType())
4012 Record = RT->getDecl();
4013 else if (const RecordType *UT = DS.getRepAsType().get()->getAsUnionType())
4014 Record = UT->getDecl();
4016 if (Record && getLangOpts().MicrosoftExt) {
4017 Diag(DS.getLocStart(), diag::ext_ms_anonymous_record)
4018 << Record->isUnion() << DS.getSourceRange();
4019 return BuildMicrosoftCAnonymousStruct(S, DS, Record);
4022 DeclaresAnything = false;
4026 // Skip all the checks below if we have a type error.
4027 if (DS.getTypeSpecType() == DeclSpec::TST_error ||
4028 (TagD && TagD->isInvalidDecl()))
4031 if (getLangOpts().CPlusPlus &&
4032 DS.getStorageClassSpec() != DeclSpec::SCS_typedef)
4033 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag))
4034 if (Enum->enumerator_begin() == Enum->enumerator_end() &&
4035 !Enum->getIdentifier() && !Enum->isInvalidDecl())
4036 DeclaresAnything = false;
4038 if (!DS.isMissingDeclaratorOk()) {
4039 // Customize diagnostic for a typedef missing a name.
4040 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
4041 Diag(DS.getLocStart(), diag::ext_typedef_without_a_name)
4042 << DS.getSourceRange();
4044 DeclaresAnything = false;
4047 if (DS.isModulePrivateSpecified() &&
4048 Tag && Tag->getDeclContext()->isFunctionOrMethod())
4049 Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class)
4050 << Tag->getTagKind()
4051 << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc());
4053 ActOnDocumentableDecl(TagD);
4056 // A declaration [...] shall declare at least a declarator [...], a tag,
4057 // or the members of an enumeration.
4059 // [If there are no declarators], and except for the declaration of an
4060 // unnamed bit-field, the decl-specifier-seq shall introduce one or more
4061 // names into the program, or shall redeclare a name introduced by a
4062 // previous declaration.
4063 if (!DeclaresAnything) {
4064 // In C, we allow this as a (popular) extension / bug. Don't bother
4065 // producing further diagnostics for redundant qualifiers after this.
4066 Diag(DS.getLocStart(), diag::ext_no_declarators) << DS.getSourceRange();
4071 // If a storage-class-specifier appears in a decl-specifier-seq, [...] the
4072 // init-declarator-list of the declaration shall not be empty.
4073 // C++ [dcl.fct.spec]p1:
4074 // If a cv-qualifier appears in a decl-specifier-seq, the
4075 // init-declarator-list of the declaration shall not be empty.
4077 // Spurious qualifiers here appear to be valid in C.
4078 unsigned DiagID = diag::warn_standalone_specifier;
4079 if (getLangOpts().CPlusPlus)
4080 DiagID = diag::ext_standalone_specifier;
4082 // Note that a linkage-specification sets a storage class, but
4083 // 'extern "C" struct foo;' is actually valid and not theoretically
4085 if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
4086 if (SCS == DeclSpec::SCS_mutable)
4087 // Since mutable is not a viable storage class specifier in C, there is
4088 // no reason to treat it as an extension. Instead, diagnose as an error.
4089 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_nonmember);
4090 else if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef)
4091 Diag(DS.getStorageClassSpecLoc(), DiagID)
4092 << DeclSpec::getSpecifierName(SCS);
4095 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
4096 Diag(DS.getThreadStorageClassSpecLoc(), DiagID)
4097 << DeclSpec::getSpecifierName(TSCS);
4098 if (DS.getTypeQualifiers()) {
4099 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4100 Diag(DS.getConstSpecLoc(), DiagID) << "const";
4101 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4102 Diag(DS.getConstSpecLoc(), DiagID) << "volatile";
4103 // Restrict is covered above.
4104 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4105 Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic";
4106 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4107 Diag(DS.getUnalignedSpecLoc(), DiagID) << "__unaligned";
4110 // Warn about ignored type attributes, for example:
4111 // __attribute__((aligned)) struct A;
4112 // Attributes should be placed after tag to apply to type declaration.
4113 if (!DS.getAttributes().empty()) {
4114 DeclSpec::TST TypeSpecType = DS.getTypeSpecType();
4115 if (TypeSpecType == DeclSpec::TST_class ||
4116 TypeSpecType == DeclSpec::TST_struct ||
4117 TypeSpecType == DeclSpec::TST_interface ||
4118 TypeSpecType == DeclSpec::TST_union ||
4119 TypeSpecType == DeclSpec::TST_enum) {
4120 for (AttributeList* attrs = DS.getAttributes().getList(); attrs;
4121 attrs = attrs->getNext())
4122 Diag(attrs->getLoc(), diag::warn_declspec_attribute_ignored)
4123 << attrs->getName() << GetDiagnosticTypeSpecifierID(TypeSpecType);
4130 /// We are trying to inject an anonymous member into the given scope;
4131 /// check if there's an existing declaration that can't be overloaded.
4133 /// \return true if this is a forbidden redeclaration
4134 static bool CheckAnonMemberRedeclaration(Sema &SemaRef,
4137 DeclarationName Name,
4138 SourceLocation NameLoc,
4140 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName,
4141 Sema::ForRedeclaration);
4142 if (!SemaRef.LookupName(R, S)) return false;
4144 // Pick a representative declaration.
4145 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl();
4146 assert(PrevDecl && "Expected a non-null Decl");
4148 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S))
4151 SemaRef.Diag(NameLoc, diag::err_anonymous_record_member_redecl)
4153 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
4158 /// InjectAnonymousStructOrUnionMembers - Inject the members of the
4159 /// anonymous struct or union AnonRecord into the owning context Owner
4160 /// and scope S. This routine will be invoked just after we realize
4161 /// that an unnamed union or struct is actually an anonymous union or
4168 /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and
4169 /// // f into the surrounding scope.x
4172 /// This routine is recursive, injecting the names of nested anonymous
4173 /// structs/unions into the owning context and scope as well.
4175 InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, DeclContext *Owner,
4176 RecordDecl *AnonRecord, AccessSpecifier AS,
4177 SmallVectorImpl<NamedDecl *> &Chaining) {
4178 bool Invalid = false;
4180 // Look every FieldDecl and IndirectFieldDecl with a name.
4181 for (auto *D : AnonRecord->decls()) {
4182 if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) &&
4183 cast<NamedDecl>(D)->getDeclName()) {
4184 ValueDecl *VD = cast<ValueDecl>(D);
4185 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(),
4187 AnonRecord->isUnion())) {
4188 // C++ [class.union]p2:
4189 // The names of the members of an anonymous union shall be
4190 // distinct from the names of any other entity in the
4191 // scope in which the anonymous union is declared.
4194 // C++ [class.union]p2:
4195 // For the purpose of name lookup, after the anonymous union
4196 // definition, the members of the anonymous union are
4197 // considered to have been defined in the scope in which the
4198 // anonymous union is declared.
4199 unsigned OldChainingSize = Chaining.size();
4200 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD))
4201 Chaining.append(IF->chain_begin(), IF->chain_end());
4203 Chaining.push_back(VD);
4205 assert(Chaining.size() >= 2);
4206 NamedDecl **NamedChain =
4207 new (SemaRef.Context)NamedDecl*[Chaining.size()];
4208 for (unsigned i = 0; i < Chaining.size(); i++)
4209 NamedChain[i] = Chaining[i];
4211 IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
4212 SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(),
4213 VD->getType(), {NamedChain, Chaining.size()});
4215 for (const auto *Attr : VD->attrs())
4216 IndirectField->addAttr(Attr->clone(SemaRef.Context));
4218 IndirectField->setAccess(AS);
4219 IndirectField->setImplicit();
4220 SemaRef.PushOnScopeChains(IndirectField, S);
4222 // That includes picking up the appropriate access specifier.
4223 if (AS != AS_none) IndirectField->setAccess(AS);
4225 Chaining.resize(OldChainingSize);
4233 /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to
4234 /// a VarDecl::StorageClass. Any error reporting is up to the caller:
4235 /// illegal input values are mapped to SC_None.
4237 StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) {
4238 DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec();
4239 assert(StorageClassSpec != DeclSpec::SCS_typedef &&
4240 "Parser allowed 'typedef' as storage class VarDecl.");
4241 switch (StorageClassSpec) {
4242 case DeclSpec::SCS_unspecified: return SC_None;
4243 case DeclSpec::SCS_extern:
4244 if (DS.isExternInLinkageSpec())
4247 case DeclSpec::SCS_static: return SC_Static;
4248 case DeclSpec::SCS_auto: return SC_Auto;
4249 case DeclSpec::SCS_register: return SC_Register;
4250 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
4251 // Illegal SCSs map to None: error reporting is up to the caller.
4252 case DeclSpec::SCS_mutable: // Fall through.
4253 case DeclSpec::SCS_typedef: return SC_None;
4255 llvm_unreachable("unknown storage class specifier");
4258 static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) {
4259 assert(Record->hasInClassInitializer());
4261 for (const auto *I : Record->decls()) {
4262 const auto *FD = dyn_cast<FieldDecl>(I);
4263 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
4264 FD = IFD->getAnonField();
4265 if (FD && FD->hasInClassInitializer())
4266 return FD->getLocation();
4269 llvm_unreachable("couldn't find in-class initializer");
4272 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4273 SourceLocation DefaultInitLoc) {
4274 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4277 S.Diag(DefaultInitLoc, diag::err_multiple_mem_union_initialization);
4278 S.Diag(findDefaultInitializer(Parent), diag::note_previous_initializer) << 0;
4281 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
4282 CXXRecordDecl *AnonUnion) {
4283 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
4286 checkDuplicateDefaultInit(S, Parent, findDefaultInitializer(AnonUnion));
4289 /// BuildAnonymousStructOrUnion - Handle the declaration of an
4290 /// anonymous structure or union. Anonymous unions are a C++ feature
4291 /// (C++ [class.union]) and a C11 feature; anonymous structures
4292 /// are a C11 feature and GNU C++ extension.
4293 Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
4296 const PrintingPolicy &Policy) {
4297 DeclContext *Owner = Record->getDeclContext();
4299 // Diagnose whether this anonymous struct/union is an extension.
4300 if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11)
4301 Diag(Record->getLocation(), diag::ext_anonymous_union);
4302 else if (!Record->isUnion() && getLangOpts().CPlusPlus)
4303 Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct);
4304 else if (!Record->isUnion() && !getLangOpts().C11)
4305 Diag(Record->getLocation(), diag::ext_c11_anonymous_struct);
4307 // C and C++ require different kinds of checks for anonymous
4309 bool Invalid = false;
4310 if (getLangOpts().CPlusPlus) {
4311 const char *PrevSpec = nullptr;
4313 if (Record->isUnion()) {
4314 // C++ [class.union]p6:
4315 // Anonymous unions declared in a named namespace or in the
4316 // global namespace shall be declared static.
4317 if (DS.getStorageClassSpec() != DeclSpec::SCS_static &&
4318 (isa<TranslationUnitDecl>(Owner) ||
4319 (isa<NamespaceDecl>(Owner) &&
4320 cast<NamespaceDecl>(Owner)->getDeclName()))) {
4321 Diag(Record->getLocation(), diag::err_anonymous_union_not_static)
4322 << FixItHint::CreateInsertion(Record->getLocation(), "static ");
4324 // Recover by adding 'static'.
4325 DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(),
4326 PrevSpec, DiagID, Policy);
4328 // C++ [class.union]p6:
4329 // A storage class is not allowed in a declaration of an
4330 // anonymous union in a class scope.
4331 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
4332 isa<RecordDecl>(Owner)) {
4333 Diag(DS.getStorageClassSpecLoc(),
4334 diag::err_anonymous_union_with_storage_spec)
4335 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
4337 // Recover by removing the storage specifier.
4338 DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified,
4340 PrevSpec, DiagID, Context.getPrintingPolicy());
4344 // Ignore const/volatile/restrict qualifiers.
4345 if (DS.getTypeQualifiers()) {
4346 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
4347 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified)
4348 << Record->isUnion() << "const"
4349 << FixItHint::CreateRemoval(DS.getConstSpecLoc());
4350 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
4351 Diag(DS.getVolatileSpecLoc(),
4352 diag::ext_anonymous_struct_union_qualified)
4353 << Record->isUnion() << "volatile"
4354 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc());
4355 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
4356 Diag(DS.getRestrictSpecLoc(),
4357 diag::ext_anonymous_struct_union_qualified)
4358 << Record->isUnion() << "restrict"
4359 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc());
4360 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
4361 Diag(DS.getAtomicSpecLoc(),
4362 diag::ext_anonymous_struct_union_qualified)
4363 << Record->isUnion() << "_Atomic"
4364 << FixItHint::CreateRemoval(DS.getAtomicSpecLoc());
4365 if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
4366 Diag(DS.getUnalignedSpecLoc(),
4367 diag::ext_anonymous_struct_union_qualified)
4368 << Record->isUnion() << "__unaligned"
4369 << FixItHint::CreateRemoval(DS.getUnalignedSpecLoc());
4371 DS.ClearTypeQualifiers();
4374 // C++ [class.union]p2:
4375 // The member-specification of an anonymous union shall only
4376 // define non-static data members. [Note: nested types and
4377 // functions cannot be declared within an anonymous union. ]
4378 for (auto *Mem : Record->decls()) {
4379 if (auto *FD = dyn_cast<FieldDecl>(Mem)) {
4380 // C++ [class.union]p3:
4381 // An anonymous union shall not have private or protected
4382 // members (clause 11).
4383 assert(FD->getAccess() != AS_none);
4384 if (FD->getAccess() != AS_public) {
4385 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member)
4386 << Record->isUnion() << (FD->getAccess() == AS_protected);
4390 // C++ [class.union]p1
4391 // An object of a class with a non-trivial constructor, a non-trivial
4392 // copy constructor, a non-trivial destructor, or a non-trivial copy
4393 // assignment operator cannot be a member of a union, nor can an
4394 // array of such objects.
4395 if (CheckNontrivialField(FD))
4397 } else if (Mem->isImplicit()) {
4398 // Any implicit members are fine.
4399 } else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) {
4400 // This is a type that showed up in an
4401 // elaborated-type-specifier inside the anonymous struct or
4402 // union, but which actually declares a type outside of the
4403 // anonymous struct or union. It's okay.
4404 } else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) {
4405 if (!MemRecord->isAnonymousStructOrUnion() &&
4406 MemRecord->getDeclName()) {
4407 // Visual C++ allows type definition in anonymous struct or union.
4408 if (getLangOpts().MicrosoftExt)
4409 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type)
4410 << Record->isUnion();
4412 // This is a nested type declaration.
4413 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type)
4414 << Record->isUnion();
4418 // This is an anonymous type definition within another anonymous type.
4419 // This is a popular extension, provided by Plan9, MSVC and GCC, but
4420 // not part of standard C++.
4421 Diag(MemRecord->getLocation(),
4422 diag::ext_anonymous_record_with_anonymous_type)
4423 << Record->isUnion();
4425 } else if (isa<AccessSpecDecl>(Mem)) {
4426 // Any access specifier is fine.
4427 } else if (isa<StaticAssertDecl>(Mem)) {
4428 // In C++1z, static_assert declarations are also fine.
4430 // We have something that isn't a non-static data
4431 // member. Complain about it.
4432 unsigned DK = diag::err_anonymous_record_bad_member;
4433 if (isa<TypeDecl>(Mem))
4434 DK = diag::err_anonymous_record_with_type;
4435 else if (isa<FunctionDecl>(Mem))
4436 DK = diag::err_anonymous_record_with_function;
4437 else if (isa<VarDecl>(Mem))
4438 DK = diag::err_anonymous_record_with_static;
4440 // Visual C++ allows type definition in anonymous struct or union.
4441 if (getLangOpts().MicrosoftExt &&
4442 DK == diag::err_anonymous_record_with_type)
4443 Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type)
4444 << Record->isUnion();
4446 Diag(Mem->getLocation(), DK) << Record->isUnion();
4452 // C++11 [class.union]p8 (DR1460):
4453 // At most one variant member of a union may have a
4454 // brace-or-equal-initializer.
4455 if (cast<CXXRecordDecl>(Record)->hasInClassInitializer() &&
4457 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Owner),
4458 cast<CXXRecordDecl>(Record));
4461 if (!Record->isUnion() && !Owner->isRecord()) {
4462 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member)
4463 << getLangOpts().CPlusPlus;
4467 // Mock up a declarator.
4468 Declarator Dc(DS, Declarator::MemberContext);
4469 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4470 assert(TInfo && "couldn't build declarator info for anonymous struct/union");
4472 // Create a declaration for this anonymous struct/union.
4473 NamedDecl *Anon = nullptr;
4474 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) {
4475 Anon = FieldDecl::Create(Context, OwningClass,
4477 Record->getLocation(),
4478 /*IdentifierInfo=*/nullptr,
4479 Context.getTypeDeclType(Record),
4481 /*BitWidth=*/nullptr, /*Mutable=*/false,
4482 /*InitStyle=*/ICIS_NoInit);
4483 Anon->setAccess(AS);
4484 if (getLangOpts().CPlusPlus)
4485 FieldCollector->Add(cast<FieldDecl>(Anon));
4487 DeclSpec::SCS SCSpec = DS.getStorageClassSpec();
4488 StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS);
4489 if (SCSpec == DeclSpec::SCS_mutable) {
4490 // mutable can only appear on non-static class members, so it's always
4492 Diag(Record->getLocation(), diag::err_mutable_nonmember);
4497 Anon = VarDecl::Create(Context, Owner,
4499 Record->getLocation(), /*IdentifierInfo=*/nullptr,
4500 Context.getTypeDeclType(Record),
4503 // Default-initialize the implicit variable. This initialization will be
4504 // trivial in almost all cases, except if a union member has an in-class
4506 // union { int n = 0; };
4507 ActOnUninitializedDecl(Anon);
4509 Anon->setImplicit();
4511 // Mark this as an anonymous struct/union type.
4512 Record->setAnonymousStructOrUnion(true);
4514 // Add the anonymous struct/union object to the current
4515 // context. We'll be referencing this object when we refer to one of
4517 Owner->addDecl(Anon);
4519 // Inject the members of the anonymous struct/union into the owning
4520 // context and into the identifier resolver chain for name lookup
4522 SmallVector<NamedDecl*, 2> Chain;
4523 Chain.push_back(Anon);
4525 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, Chain))
4528 if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) {
4529 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
4530 Decl *ManglingContextDecl;
4531 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
4532 NewVD->getDeclContext(), ManglingContextDecl)) {
4533 Context.setManglingNumber(
4534 NewVD, MCtx->getManglingNumber(
4535 NewVD, getMSManglingNumber(getLangOpts(), S)));
4536 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
4542 Anon->setInvalidDecl();
4547 /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an
4548 /// Microsoft C anonymous structure.
4549 /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx
4552 /// struct A { int a; };
4553 /// struct B { struct A; int b; };
4560 Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
4561 RecordDecl *Record) {
4562 assert(Record && "expected a record!");
4564 // Mock up a declarator.
4565 Declarator Dc(DS, Declarator::TypeNameContext);
4566 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4567 assert(TInfo && "couldn't build declarator info for anonymous struct");
4569 auto *ParentDecl = cast<RecordDecl>(CurContext);
4570 QualType RecTy = Context.getTypeDeclType(Record);
4572 // Create a declaration for this anonymous struct.
4573 NamedDecl *Anon = FieldDecl::Create(Context,
4577 /*IdentifierInfo=*/nullptr,
4580 /*BitWidth=*/nullptr, /*Mutable=*/false,
4581 /*InitStyle=*/ICIS_NoInit);
4582 Anon->setImplicit();
4584 // Add the anonymous struct object to the current context.
4585 CurContext->addDecl(Anon);
4587 // Inject the members of the anonymous struct into the current
4588 // context and into the identifier resolver chain for name lookup
4590 SmallVector<NamedDecl*, 2> Chain;
4591 Chain.push_back(Anon);
4593 RecordDecl *RecordDef = Record->getDefinition();
4594 if (RequireCompleteType(Anon->getLocation(), RecTy,
4595 diag::err_field_incomplete) ||
4596 InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef,
4598 Anon->setInvalidDecl();
4599 ParentDecl->setInvalidDecl();
4605 /// GetNameForDeclarator - Determine the full declaration name for the
4606 /// given Declarator.
4607 DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) {
4608 return GetNameFromUnqualifiedId(D.getName());
4611 /// \brief Retrieves the declaration name from a parsed unqualified-id.
4613 Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
4614 DeclarationNameInfo NameInfo;
4615 NameInfo.setLoc(Name.StartLocation);
4617 switch (Name.getKind()) {
4619 case UnqualifiedId::IK_ImplicitSelfParam:
4620 case UnqualifiedId::IK_Identifier:
4621 NameInfo.setName(Name.Identifier);
4622 NameInfo.setLoc(Name.StartLocation);
4625 case UnqualifiedId::IK_OperatorFunctionId:
4626 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName(
4627 Name.OperatorFunctionId.Operator));
4628 NameInfo.setLoc(Name.StartLocation);
4629 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc
4630 = Name.OperatorFunctionId.SymbolLocations[0];
4631 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc
4632 = Name.EndLocation.getRawEncoding();
4635 case UnqualifiedId::IK_LiteralOperatorId:
4636 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName(
4638 NameInfo.setLoc(Name.StartLocation);
4639 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation);
4642 case UnqualifiedId::IK_ConversionFunctionId: {
4643 TypeSourceInfo *TInfo;
4644 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo);
4646 return DeclarationNameInfo();
4647 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName(
4648 Context.getCanonicalType(Ty)));
4649 NameInfo.setLoc(Name.StartLocation);
4650 NameInfo.setNamedTypeInfo(TInfo);
4654 case UnqualifiedId::IK_ConstructorName: {
4655 TypeSourceInfo *TInfo;
4656 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo);
4658 return DeclarationNameInfo();
4659 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4660 Context.getCanonicalType(Ty)));
4661 NameInfo.setLoc(Name.StartLocation);
4662 NameInfo.setNamedTypeInfo(TInfo);
4666 case UnqualifiedId::IK_ConstructorTemplateId: {
4667 // In well-formed code, we can only have a constructor
4668 // template-id that refers to the current context, so go there
4669 // to find the actual type being constructed.
4670 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext);
4671 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name)
4672 return DeclarationNameInfo();
4674 // Determine the type of the class being constructed.
4675 QualType CurClassType = Context.getTypeDeclType(CurClass);
4677 // FIXME: Check two things: that the template-id names the same type as
4678 // CurClassType, and that the template-id does not occur when the name
4681 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4682 Context.getCanonicalType(CurClassType)));
4683 NameInfo.setLoc(Name.StartLocation);
4684 // FIXME: should we retrieve TypeSourceInfo?
4685 NameInfo.setNamedTypeInfo(nullptr);
4689 case UnqualifiedId::IK_DestructorName: {
4690 TypeSourceInfo *TInfo;
4691 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo);
4693 return DeclarationNameInfo();
4694 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName(
4695 Context.getCanonicalType(Ty)));
4696 NameInfo.setLoc(Name.StartLocation);
4697 NameInfo.setNamedTypeInfo(TInfo);
4701 case UnqualifiedId::IK_TemplateId: {
4702 TemplateName TName = Name.TemplateId->Template.get();
4703 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc;
4704 return Context.getNameForTemplate(TName, TNameLoc);
4707 } // switch (Name.getKind())
4709 llvm_unreachable("Unknown name kind");
4712 static QualType getCoreType(QualType Ty) {
4714 if (Ty->isPointerType() || Ty->isReferenceType())
4715 Ty = Ty->getPointeeType();
4716 else if (Ty->isArrayType())
4717 Ty = Ty->castAsArrayTypeUnsafe()->getElementType();
4719 return Ty.withoutLocalFastQualifiers();
4723 /// hasSimilarParameters - Determine whether the C++ functions Declaration
4724 /// and Definition have "nearly" matching parameters. This heuristic is
4725 /// used to improve diagnostics in the case where an out-of-line function
4726 /// definition doesn't match any declaration within the class or namespace.
4727 /// Also sets Params to the list of indices to the parameters that differ
4728 /// between the declaration and the definition. If hasSimilarParameters
4729 /// returns true and Params is empty, then all of the parameters match.
4730 static bool hasSimilarParameters(ASTContext &Context,
4731 FunctionDecl *Declaration,
4732 FunctionDecl *Definition,
4733 SmallVectorImpl<unsigned> &Params) {
4735 if (Declaration->param_size() != Definition->param_size())
4737 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) {
4738 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType();
4739 QualType DefParamTy = Definition->getParamDecl(Idx)->getType();
4741 // The parameter types are identical
4742 if (Context.hasSameType(DefParamTy, DeclParamTy))
4745 QualType DeclParamBaseTy = getCoreType(DeclParamTy);
4746 QualType DefParamBaseTy = getCoreType(DefParamTy);
4747 const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier();
4748 const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier();
4750 if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) ||
4751 (DeclTyName && DeclTyName == DefTyName))
4752 Params.push_back(Idx);
4753 else // The two parameters aren't even close
4760 /// NeedsRebuildingInCurrentInstantiation - Checks whether the given
4761 /// declarator needs to be rebuilt in the current instantiation.
4762 /// Any bits of declarator which appear before the name are valid for
4763 /// consideration here. That's specifically the type in the decl spec
4764 /// and the base type in any member-pointer chunks.
4765 static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D,
4766 DeclarationName Name) {
4767 // The types we specifically need to rebuild are:
4768 // - typenames, typeofs, and decltypes
4769 // - types which will become injected class names
4770 // Of course, we also need to rebuild any type referencing such a
4771 // type. It's safest to just say "dependent", but we call out a
4774 DeclSpec &DS = D.getMutableDeclSpec();
4775 switch (DS.getTypeSpecType()) {
4776 case DeclSpec::TST_typename:
4777 case DeclSpec::TST_typeofType:
4778 case DeclSpec::TST_underlyingType:
4779 case DeclSpec::TST_atomic: {
4780 // Grab the type from the parser.
4781 TypeSourceInfo *TSI = nullptr;
4782 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI);
4783 if (T.isNull() || !T->isDependentType()) break;
4785 // Make sure there's a type source info. This isn't really much
4786 // of a waste; most dependent types should have type source info
4787 // attached already.
4789 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc());
4791 // Rebuild the type in the current instantiation.
4792 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name);
4793 if (!TSI) return true;
4795 // Store the new type back in the decl spec.
4796 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI);
4797 DS.UpdateTypeRep(LocType);
4801 case DeclSpec::TST_decltype:
4802 case DeclSpec::TST_typeofExpr: {
4803 Expr *E = DS.getRepAsExpr();
4804 ExprResult Result = S.RebuildExprInCurrentInstantiation(E);
4805 if (Result.isInvalid()) return true;
4806 DS.UpdateExprRep(Result.get());
4811 // Nothing to do for these decl specs.
4815 // It doesn't matter what order we do this in.
4816 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
4817 DeclaratorChunk &Chunk = D.getTypeObject(I);
4819 // The only type information in the declarator which can come
4820 // before the declaration name is the base type of a member
4822 if (Chunk.Kind != DeclaratorChunk::MemberPointer)
4825 // Rebuild the scope specifier in-place.
4826 CXXScopeSpec &SS = Chunk.Mem.Scope();
4827 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS))
4834 Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) {
4835 D.setFunctionDefinitionKind(FDK_Declaration);
4836 Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg());
4838 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() &&
4839 Dcl && Dcl->getDeclContext()->isFileContext())
4840 Dcl->setTopLevelDeclInObjCContainer();
4842 if (getLangOpts().OpenCL)
4843 setCurrentOpenCLExtensionForDecl(Dcl);
4848 /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13:
4849 /// If T is the name of a class, then each of the following shall have a
4850 /// name different from T:
4851 /// - every static data member of class T;
4852 /// - every member function of class T
4853 /// - every member of class T that is itself a type;
4854 /// \returns true if the declaration name violates these rules.
4855 bool Sema::DiagnoseClassNameShadow(DeclContext *DC,
4856 DeclarationNameInfo NameInfo) {
4857 DeclarationName Name = NameInfo.getName();
4859 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC);
4860 while (Record && Record->isAnonymousStructOrUnion())
4861 Record = dyn_cast<CXXRecordDecl>(Record->getParent());
4862 if (Record && Record->getIdentifier() && Record->getDeclName() == Name) {
4863 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name;
4870 /// \brief Diagnose a declaration whose declarator-id has the given
4871 /// nested-name-specifier.
4873 /// \param SS The nested-name-specifier of the declarator-id.
4875 /// \param DC The declaration context to which the nested-name-specifier
4878 /// \param Name The name of the entity being declared.
4880 /// \param Loc The location of the name of the entity being declared.
4882 /// \returns true if we cannot safely recover from this error, false otherwise.
4883 bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
4884 DeclarationName Name,
4885 SourceLocation Loc) {
4886 DeclContext *Cur = CurContext;
4887 while (isa<LinkageSpecDecl>(Cur) || isa<CapturedDecl>(Cur))
4888 Cur = Cur->getParent();
4890 // If the user provided a superfluous scope specifier that refers back to the
4891 // class in which the entity is already declared, diagnose and ignore it.
4897 // Note, it was once ill-formed to give redundant qualification in all
4898 // contexts, but that rule was removed by DR482.
4899 if (Cur->Equals(DC)) {
4900 if (Cur->isRecord()) {
4901 Diag(Loc, LangOpts.MicrosoftExt ? diag::warn_member_extra_qualification
4902 : diag::err_member_extra_qualification)
4903 << Name << FixItHint::CreateRemoval(SS.getRange());
4906 Diag(Loc, diag::warn_namespace_member_extra_qualification) << Name;
4911 // Check whether the qualifying scope encloses the scope of the original
4913 if (!Cur->Encloses(DC)) {
4914 if (Cur->isRecord())
4915 Diag(Loc, diag::err_member_qualification)
4916 << Name << SS.getRange();
4917 else if (isa<TranslationUnitDecl>(DC))
4918 Diag(Loc, diag::err_invalid_declarator_global_scope)
4919 << Name << SS.getRange();
4920 else if (isa<FunctionDecl>(Cur))
4921 Diag(Loc, diag::err_invalid_declarator_in_function)
4922 << Name << SS.getRange();
4923 else if (isa<BlockDecl>(Cur))
4924 Diag(Loc, diag::err_invalid_declarator_in_block)
4925 << Name << SS.getRange();
4927 Diag(Loc, diag::err_invalid_declarator_scope)
4928 << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange();
4933 if (Cur->isRecord()) {
4934 // Cannot qualify members within a class.
4935 Diag(Loc, diag::err_member_qualification)
4936 << Name << SS.getRange();
4939 // C++ constructors and destructors with incorrect scopes can break
4940 // our AST invariants by having the wrong underlying types. If
4941 // that's the case, then drop this declaration entirely.
4942 if ((Name.getNameKind() == DeclarationName::CXXConstructorName ||
4943 Name.getNameKind() == DeclarationName::CXXDestructorName) &&
4944 !Context.hasSameType(Name.getCXXNameType(),
4945 Context.getTypeDeclType(cast<CXXRecordDecl>(Cur))))
4951 // C++11 [dcl.meaning]p1:
4952 // [...] "The nested-name-specifier of the qualified declarator-id shall
4953 // not begin with a decltype-specifer"
4954 NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data());
4955 while (SpecLoc.getPrefix())
4956 SpecLoc = SpecLoc.getPrefix();
4957 if (dyn_cast_or_null<DecltypeType>(
4958 SpecLoc.getNestedNameSpecifier()->getAsType()))
4959 Diag(Loc, diag::err_decltype_in_declarator)
4960 << SpecLoc.getTypeLoc().getSourceRange();
4965 NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
4966 MultiTemplateParamsArg TemplateParamLists) {
4967 // TODO: consider using NameInfo for diagnostic.
4968 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
4969 DeclarationName Name = NameInfo.getName();
4971 // All of these full declarators require an identifier. If it doesn't have
4972 // one, the ParsedFreeStandingDeclSpec action should be used.
4973 if (D.isDecompositionDeclarator()) {
4974 return ActOnDecompositionDeclarator(S, D, TemplateParamLists);
4976 if (!D.isInvalidType()) // Reject this if we think it is valid.
4977 Diag(D.getDeclSpec().getLocStart(),
4978 diag::err_declarator_need_ident)
4979 << D.getDeclSpec().getSourceRange() << D.getSourceRange();
4981 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType))
4984 // The scope passed in may not be a decl scope. Zip up the scope tree until
4985 // we find one that is.
4986 while ((S->getFlags() & Scope::DeclScope) == 0 ||
4987 (S->getFlags() & Scope::TemplateParamScope) != 0)
4990 DeclContext *DC = CurContext;
4991 if (D.getCXXScopeSpec().isInvalid())
4993 else if (D.getCXXScopeSpec().isSet()) {
4994 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(),
4995 UPPC_DeclarationQualifier))
4998 bool EnteringContext = !D.getDeclSpec().isFriendSpecified();
4999 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext);
5000 if (!DC || isa<EnumDecl>(DC)) {
5001 // If we could not compute the declaration context, it's because the
5002 // declaration context is dependent but does not refer to a class,
5003 // class template, or class template partial specialization. Complain
5004 // and return early, to avoid the coming semantic disaster.
5005 Diag(D.getIdentifierLoc(),
5006 diag::err_template_qualified_declarator_no_match)
5007 << D.getCXXScopeSpec().getScopeRep()
5008 << D.getCXXScopeSpec().getRange();
5011 bool IsDependentContext = DC->isDependentContext();
5013 if (!IsDependentContext &&
5014 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC))
5017 // If a class is incomplete, do not parse entities inside it.
5018 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) {
5019 Diag(D.getIdentifierLoc(),
5020 diag::err_member_def_undefined_record)
5021 << Name << DC << D.getCXXScopeSpec().getRange();
5024 if (!D.getDeclSpec().isFriendSpecified()) {
5025 if (diagnoseQualifiedDeclaration(D.getCXXScopeSpec(), DC,
5026 Name, D.getIdentifierLoc())) {
5034 // Check whether we need to rebuild the type of the given
5035 // declaration in the current instantiation.
5036 if (EnteringContext && IsDependentContext &&
5037 TemplateParamLists.size() != 0) {
5038 ContextRAII SavedContext(*this, DC);
5039 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name))
5044 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
5045 QualType R = TInfo->getType();
5047 if (!R->isFunctionType() && DiagnoseClassNameShadow(DC, NameInfo))
5048 // If this is a typedef, we'll end up spewing multiple diagnostics.
5049 // Just return early; it's safer. If this is a function, let the
5050 // "constructor cannot have a return type" diagnostic handle it.
5051 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
5054 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
5055 UPPC_DeclarationType))
5058 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
5061 // See if this is a redefinition of a variable in the same scope.
5062 if (!D.getCXXScopeSpec().isSet()) {
5063 bool IsLinkageLookup = false;
5064 bool CreateBuiltins = false;
5066 // If the declaration we're planning to build will be a function
5067 // or object with linkage, then look for another declaration with
5068 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6).
5070 // If the declaration we're planning to build will be declared with
5071 // external linkage in the translation unit, create any builtin with
5073 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
5075 else if (CurContext->isFunctionOrMethod() &&
5076 (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern ||
5077 R->isFunctionType())) {
5078 IsLinkageLookup = true;
5080 CurContext->getEnclosingNamespaceContext()->isTranslationUnit();
5081 } else if (CurContext->getRedeclContext()->isTranslationUnit() &&
5082 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
5083 CreateBuiltins = true;
5085 if (IsLinkageLookup)
5086 Previous.clear(LookupRedeclarationWithLinkage);
5088 LookupName(Previous, S, CreateBuiltins);
5089 } else { // Something like "int foo::x;"
5090 LookupQualifiedName(Previous, DC);
5092 // C++ [dcl.meaning]p1:
5093 // When the declarator-id is qualified, the declaration shall refer to a
5094 // previously declared member of the class or namespace to which the
5095 // qualifier refers (or, in the case of a namespace, of an element of the
5096 // inline namespace set of that namespace (7.3.1)) or to a specialization
5099 // Note that we already checked the context above, and that we do not have
5100 // enough information to make sure that Previous contains the declaration
5101 // we want to match. For example, given:
5108 // void X::f(int) { } // ill-formed
5110 // In this case, Previous will point to the overload set
5111 // containing the two f's declared in X, but neither of them
5114 // C++ [dcl.meaning]p1:
5115 // [...] the member shall not merely have been introduced by a
5116 // using-declaration in the scope of the class or namespace nominated by
5117 // the nested-name-specifier of the declarator-id.
5118 RemoveUsingDecls(Previous);
5121 if (Previous.isSingleResult() &&
5122 Previous.getFoundDecl()->isTemplateParameter()) {
5123 // Maybe we will complain about the shadowed template parameter.
5124 if (!D.isInvalidType())
5125 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
5126 Previous.getFoundDecl());
5128 // Just pretend that we didn't see the previous declaration.
5132 // In C++, the previous declaration we find might be a tag type
5133 // (class or enum). In this case, the new declaration will hide the
5134 // tag type. Note that this does does not apply if we're declaring a
5135 // typedef (C++ [dcl.typedef]p4).
5136 if (Previous.isSingleTagDecl() &&
5137 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef)
5140 // Check that there are no default arguments other than in the parameters
5141 // of a function declaration (C++ only).
5142 if (getLangOpts().CPlusPlus)
5143 CheckExtraCXXDefaultArguments(D);
5145 if (D.getDeclSpec().isConceptSpecified()) {
5146 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
5147 // applied only to the definition of a function template or variable
5148 // template, declared in namespace scope
5149 if (!TemplateParamLists.size()) {
5150 Diag(D.getDeclSpec().getConceptSpecLoc(),
5151 diag:: err_concept_wrong_decl_kind);
5155 if (!DC->getRedeclContext()->isFileContext()) {
5156 Diag(D.getIdentifierLoc(),
5157 diag::err_concept_decls_may_only_appear_in_namespace_scope);
5164 bool AddToScope = true;
5165 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
5166 if (TemplateParamLists.size()) {
5167 Diag(D.getIdentifierLoc(), diag::err_template_typedef);
5171 New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous);
5172 } else if (R->isFunctionType()) {
5173 New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous,
5177 New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists,
5184 // If this has an identifier and is not a function template specialization,
5185 // add it to the scope stack.
5186 if (New->getDeclName() && AddToScope) {
5187 // Only make a locally-scoped extern declaration visible if it is the first
5188 // declaration of this entity. Qualified lookup for such an entity should
5189 // only find this declaration if there is no visible declaration of it.
5190 bool AddToContext = !D.isRedeclaration() || !New->isLocalExternDecl();
5191 PushOnScopeChains(New, S, AddToContext);
5193 CurContext->addHiddenDecl(New);
5196 if (isInOpenMPDeclareTargetContext())
5197 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
5202 /// Helper method to turn variable array types into constant array
5203 /// types in certain situations which would otherwise be errors (for
5204 /// GCC compatibility).
5205 static QualType TryToFixInvalidVariablyModifiedType(QualType T,
5206 ASTContext &Context,
5207 bool &SizeIsNegative,
5208 llvm::APSInt &Oversized) {
5209 // This method tries to turn a variable array into a constant
5210 // array even when the size isn't an ICE. This is necessary
5211 // for compatibility with code that depends on gcc's buggy
5212 // constant expression folding, like struct {char x[(int)(char*)2];}
5213 SizeIsNegative = false;
5216 if (T->isDependentType())
5219 QualifierCollector Qs;
5220 const Type *Ty = Qs.strip(T);
5222 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) {
5223 QualType Pointee = PTy->getPointeeType();
5224 QualType FixedType =
5225 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative,
5227 if (FixedType.isNull()) return FixedType;
5228 FixedType = Context.getPointerType(FixedType);
5229 return Qs.apply(Context, FixedType);
5231 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) {
5232 QualType Inner = PTy->getInnerType();
5233 QualType FixedType =
5234 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative,
5236 if (FixedType.isNull()) return FixedType;
5237 FixedType = Context.getParenType(FixedType);
5238 return Qs.apply(Context, FixedType);
5241 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T);
5244 // FIXME: We should probably handle this case
5245 if (VLATy->getElementType()->isVariablyModifiedType())
5249 if (!VLATy->getSizeExpr() ||
5250 !VLATy->getSizeExpr()->EvaluateAsInt(Res, Context))
5253 // Check whether the array size is negative.
5254 if (Res.isSigned() && Res.isNegative()) {
5255 SizeIsNegative = true;
5259 // Check whether the array is too large to be addressed.
5260 unsigned ActiveSizeBits
5261 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(),
5263 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
5268 return Context.getConstantArrayType(VLATy->getElementType(),
5269 Res, ArrayType::Normal, 0);
5273 FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) {
5274 SrcTL = SrcTL.getUnqualifiedLoc();
5275 DstTL = DstTL.getUnqualifiedLoc();
5276 if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) {
5277 PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>();
5278 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(),
5279 DstPTL.getPointeeLoc());
5280 DstPTL.setStarLoc(SrcPTL.getStarLoc());
5283 if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) {
5284 ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>();
5285 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(),
5286 DstPTL.getInnerLoc());
5287 DstPTL.setLParenLoc(SrcPTL.getLParenLoc());
5288 DstPTL.setRParenLoc(SrcPTL.getRParenLoc());
5291 ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>();
5292 ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>();
5293 TypeLoc SrcElemTL = SrcATL.getElementLoc();
5294 TypeLoc DstElemTL = DstATL.getElementLoc();
5295 DstElemTL.initializeFullCopy(SrcElemTL);
5296 DstATL.setLBracketLoc(SrcATL.getLBracketLoc());
5297 DstATL.setSizeExpr(SrcATL.getSizeExpr());
5298 DstATL.setRBracketLoc(SrcATL.getRBracketLoc());
5301 /// Helper method to turn variable array types into constant array
5302 /// types in certain situations which would otherwise be errors (for
5303 /// GCC compatibility).
5304 static TypeSourceInfo*
5305 TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo,
5306 ASTContext &Context,
5307 bool &SizeIsNegative,
5308 llvm::APSInt &Oversized) {
5310 = TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context,
5311 SizeIsNegative, Oversized);
5312 if (FixedTy.isNull())
5314 TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy);
5315 FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(),
5316 FixedTInfo->getTypeLoc());
5320 /// \brief Register the given locally-scoped extern "C" declaration so
5321 /// that it can be found later for redeclarations. We include any extern "C"
5322 /// declaration that is not visible in the translation unit here, not just
5323 /// function-scope declarations.
5325 Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) {
5326 if (!getLangOpts().CPlusPlus &&
5327 ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit())
5328 // Don't need to track declarations in the TU in C.
5331 // Note that we have a locally-scoped external with this name.
5332 Context.getExternCContextDecl()->makeDeclVisibleInContext(ND);
5335 NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) {
5336 // FIXME: We can have multiple results via __attribute__((overloadable)).
5337 auto Result = Context.getExternCContextDecl()->lookup(Name);
5338 return Result.empty() ? nullptr : *Result.begin();
5341 /// \brief Diagnose function specifiers on a declaration of an identifier that
5342 /// does not identify a function.
5343 void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) {
5344 // FIXME: We should probably indicate the identifier in question to avoid
5345 // confusion for constructs like "virtual int a(), b;"
5346 if (DS.isVirtualSpecified())
5347 Diag(DS.getVirtualSpecLoc(),
5348 diag::err_virtual_non_function);
5350 if (DS.isExplicitSpecified())
5351 Diag(DS.getExplicitSpecLoc(),
5352 diag::err_explicit_non_function);
5354 if (DS.isNoreturnSpecified())
5355 Diag(DS.getNoreturnSpecLoc(),
5356 diag::err_noreturn_non_function);
5360 Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
5361 TypeSourceInfo *TInfo, LookupResult &Previous) {
5362 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1).
5363 if (D.getCXXScopeSpec().isSet()) {
5364 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator)
5365 << D.getCXXScopeSpec().getRange();
5367 // Pretend we didn't see the scope specifier.
5372 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5374 if (D.getDeclSpec().isInlineSpecified())
5375 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
5376 << getLangOpts().CPlusPlus1z;
5377 if (D.getDeclSpec().isConstexprSpecified())
5378 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr)
5380 if (D.getDeclSpec().isConceptSpecified())
5381 Diag(D.getDeclSpec().getConceptSpecLoc(),
5382 diag::err_concept_wrong_decl_kind);
5384 if (D.getName().Kind != UnqualifiedId::IK_Identifier) {
5385 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier)
5386 << D.getName().getSourceRange();
5390 TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo);
5391 if (!NewTD) return nullptr;
5393 // Handle attributes prior to checking for duplicates in MergeVarDecl
5394 ProcessDeclAttributes(S, NewTD, D);
5396 CheckTypedefForVariablyModifiedType(S, NewTD);
5398 bool Redeclaration = D.isRedeclaration();
5399 NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration);
5400 D.setRedeclaration(Redeclaration);
5405 Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) {
5406 // C99 6.7.7p2: If a typedef name specifies a variably modified type
5407 // then it shall have block scope.
5408 // Note that variably modified types must be fixed before merging the decl so
5409 // that redeclarations will match.
5410 TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo();
5411 QualType T = TInfo->getType();
5412 if (T->isVariablyModifiedType()) {
5413 getCurFunction()->setHasBranchProtectedScope();
5415 if (S->getFnParent() == nullptr) {
5416 bool SizeIsNegative;
5417 llvm::APSInt Oversized;
5418 TypeSourceInfo *FixedTInfo =
5419 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
5423 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size);
5424 NewTD->setTypeSourceInfo(FixedTInfo);
5427 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size);
5428 else if (T->isVariableArrayType())
5429 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope);
5430 else if (Oversized.getBoolValue())
5431 Diag(NewTD->getLocation(), diag::err_array_too_large)
5432 << Oversized.toString(10);
5434 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope);
5435 NewTD->setInvalidDecl();
5441 /// ActOnTypedefNameDecl - Perform semantic checking for a declaration which
5442 /// declares a typedef-name, either using the 'typedef' type specifier or via
5443 /// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'.
5445 Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD,
5446 LookupResult &Previous, bool &Redeclaration) {
5447 // Merge the decl with the existing one if appropriate. If the decl is
5448 // in an outer scope, it isn't the same thing.
5449 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/false,
5450 /*AllowInlineNamespace*/false);
5451 filterNonConflictingPreviousTypedefDecls(*this, NewTD, Previous);
5452 if (!Previous.empty()) {
5453 Redeclaration = true;
5454 MergeTypedefNameDecl(S, NewTD, Previous);
5457 // If this is the C FILE type, notify the AST context.
5458 if (IdentifierInfo *II = NewTD->getIdentifier())
5459 if (!NewTD->isInvalidDecl() &&
5460 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
5461 if (II->isStr("FILE"))
5462 Context.setFILEDecl(NewTD);
5463 else if (II->isStr("jmp_buf"))
5464 Context.setjmp_bufDecl(NewTD);
5465 else if (II->isStr("sigjmp_buf"))
5466 Context.setsigjmp_bufDecl(NewTD);
5467 else if (II->isStr("ucontext_t"))
5468 Context.setucontext_tDecl(NewTD);
5474 /// \brief Determines whether the given declaration is an out-of-scope
5475 /// previous declaration.
5477 /// This routine should be invoked when name lookup has found a
5478 /// previous declaration (PrevDecl) that is not in the scope where a
5479 /// new declaration by the same name is being introduced. If the new
5480 /// declaration occurs in a local scope, previous declarations with
5481 /// linkage may still be considered previous declarations (C99
5482 /// 6.2.2p4-5, C++ [basic.link]p6).
5484 /// \param PrevDecl the previous declaration found by name
5487 /// \param DC the context in which the new declaration is being
5490 /// \returns true if PrevDecl is an out-of-scope previous declaration
5491 /// for a new delcaration with the same name.
5493 isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC,
5494 ASTContext &Context) {
5498 if (!PrevDecl->hasLinkage())
5501 if (Context.getLangOpts().CPlusPlus) {
5502 // C++ [basic.link]p6:
5503 // If there is a visible declaration of an entity with linkage
5504 // having the same name and type, ignoring entities declared
5505 // outside the innermost enclosing namespace scope, the block
5506 // scope declaration declares that same entity and receives the
5507 // linkage of the previous declaration.
5508 DeclContext *OuterContext = DC->getRedeclContext();
5509 if (!OuterContext->isFunctionOrMethod())
5510 // This rule only applies to block-scope declarations.
5513 DeclContext *PrevOuterContext = PrevDecl->getDeclContext();
5514 if (PrevOuterContext->isRecord())
5515 // We found a member function: ignore it.
5518 // Find the innermost enclosing namespace for the new and
5519 // previous declarations.
5520 OuterContext = OuterContext->getEnclosingNamespaceContext();
5521 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext();
5523 // The previous declaration is in a different namespace, so it
5524 // isn't the same function.
5525 if (!OuterContext->Equals(PrevOuterContext))
5532 static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) {
5533 CXXScopeSpec &SS = D.getCXXScopeSpec();
5534 if (!SS.isSet()) return;
5535 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext()));
5538 bool Sema::inferObjCARCLifetime(ValueDecl *decl) {
5539 QualType type = decl->getType();
5540 Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime();
5541 if (lifetime == Qualifiers::OCL_Autoreleasing) {
5542 // Various kinds of declaration aren't allowed to be __autoreleasing.
5543 unsigned kind = -1U;
5544 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5545 if (var->hasAttr<BlocksAttr>())
5546 kind = 0; // __block
5547 else if (!var->hasLocalStorage())
5549 } else if (isa<ObjCIvarDecl>(decl)) {
5551 } else if (isa<FieldDecl>(decl)) {
5556 Diag(decl->getLocation(), diag::err_arc_autoreleasing_var)
5559 } else if (lifetime == Qualifiers::OCL_None) {
5560 // Try to infer lifetime.
5561 if (!type->isObjCLifetimeType())
5564 lifetime = type->getObjCARCImplicitLifetime();
5565 type = Context.getLifetimeQualifiedType(type, lifetime);
5566 decl->setType(type);
5569 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5570 // Thread-local variables cannot have lifetime.
5571 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone &&
5572 var->getTLSKind()) {
5573 Diag(var->getLocation(), diag::err_arc_thread_ownership)
5582 static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) {
5583 // Ensure that an auto decl is deduced otherwise the checks below might cache
5584 // the wrong linkage.
5585 assert(S.ParsingInitForAutoVars.count(&ND) == 0);
5587 // 'weak' only applies to declarations with external linkage.
5588 if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) {
5589 if (!ND.isExternallyVisible()) {
5590 S.Diag(Attr->getLocation(), diag::err_attribute_weak_static);
5591 ND.dropAttr<WeakAttr>();
5594 if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) {
5595 if (ND.isExternallyVisible()) {
5596 S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static);
5597 ND.dropAttr<WeakRefAttr>();
5598 ND.dropAttr<AliasAttr>();
5602 if (auto *VD = dyn_cast<VarDecl>(&ND)) {
5603 if (VD->hasInit()) {
5604 if (const auto *Attr = VD->getAttr<AliasAttr>()) {
5605 assert(VD->isThisDeclarationADefinition() &&
5606 !VD->isExternallyVisible() && "Broken AliasAttr handled late!");
5607 S.Diag(Attr->getLocation(), diag::err_alias_is_definition) << VD << 0;
5608 VD->dropAttr<AliasAttr>();
5613 // 'selectany' only applies to externally visible variable declarations.
5614 // It does not apply to functions.
5615 if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) {
5616 if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) {
5617 S.Diag(Attr->getLocation(),
5618 diag::err_attribute_selectany_non_extern_data);
5619 ND.dropAttr<SelectAnyAttr>();
5623 if (const InheritableAttr *Attr = getDLLAttr(&ND)) {
5624 // dll attributes require external linkage. Static locals may have external
5625 // linkage but still cannot be explicitly imported or exported.
5626 auto *VD = dyn_cast<VarDecl>(&ND);
5627 if (!ND.isExternallyVisible() || (VD && VD->isStaticLocal())) {
5628 S.Diag(ND.getLocation(), diag::err_attribute_dll_not_extern)
5630 ND.setInvalidDecl();
5634 // Virtual functions cannot be marked as 'notail'.
5635 if (auto *Attr = ND.getAttr<NotTailCalledAttr>())
5636 if (auto *MD = dyn_cast<CXXMethodDecl>(&ND))
5637 if (MD->isVirtual()) {
5638 S.Diag(ND.getLocation(),
5639 diag::err_invalid_attribute_on_virtual_function)
5641 ND.dropAttr<NotTailCalledAttr>();
5645 static void checkDLLAttributeRedeclaration(Sema &S, NamedDecl *OldDecl,
5647 bool IsSpecialization,
5648 bool IsDefinition) {
5649 if (OldDecl->isInvalidDecl())
5652 if (TemplateDecl *OldTD = dyn_cast<TemplateDecl>(OldDecl)) {
5653 OldDecl = OldTD->getTemplatedDecl();
5654 if (!IsSpecialization)
5655 IsDefinition = false;
5657 if (TemplateDecl *NewTD = dyn_cast<TemplateDecl>(NewDecl))
5658 NewDecl = NewTD->getTemplatedDecl();
5660 if (!OldDecl || !NewDecl)
5663 const DLLImportAttr *OldImportAttr = OldDecl->getAttr<DLLImportAttr>();
5664 const DLLExportAttr *OldExportAttr = OldDecl->getAttr<DLLExportAttr>();
5665 const DLLImportAttr *NewImportAttr = NewDecl->getAttr<DLLImportAttr>();
5666 const DLLExportAttr *NewExportAttr = NewDecl->getAttr<DLLExportAttr>();
5668 // dllimport and dllexport are inheritable attributes so we have to exclude
5669 // inherited attribute instances.
5670 bool HasNewAttr = (NewImportAttr && !NewImportAttr->isInherited()) ||
5671 (NewExportAttr && !NewExportAttr->isInherited());
5673 // A redeclaration is not allowed to add a dllimport or dllexport attribute,
5674 // the only exception being explicit specializations.
5675 // Implicitly generated declarations are also excluded for now because there
5676 // is no other way to switch these to use dllimport or dllexport.
5677 bool AddsAttr = !(OldImportAttr || OldExportAttr) && HasNewAttr;
5679 if (AddsAttr && !IsSpecialization && !OldDecl->isImplicit()) {
5680 // Allow with a warning for free functions and global variables.
5681 bool JustWarn = false;
5682 if (!OldDecl->isCXXClassMember()) {
5683 auto *VD = dyn_cast<VarDecl>(OldDecl);
5684 if (VD && !VD->getDescribedVarTemplate())
5686 auto *FD = dyn_cast<FunctionDecl>(OldDecl);
5687 if (FD && FD->getTemplatedKind() == FunctionDecl::TK_NonTemplate)
5691 // We cannot change a declaration that's been used because IR has already
5692 // been emitted. Dllimported functions will still work though (modulo
5693 // address equality) as they can use the thunk.
5694 if (OldDecl->isUsed())
5695 if (!isa<FunctionDecl>(OldDecl) || !NewImportAttr)
5698 unsigned DiagID = JustWarn ? diag::warn_attribute_dll_redeclaration
5699 : diag::err_attribute_dll_redeclaration;
5700 S.Diag(NewDecl->getLocation(), DiagID)
5702 << (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr);
5703 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5705 NewDecl->setInvalidDecl();
5710 // A redeclaration is not allowed to drop a dllimport attribute, the only
5711 // exceptions being inline function definitions, local extern declarations,
5712 // qualified friend declarations or special MSVC extension: in the last case,
5713 // the declaration is treated as if it were marked dllexport.
5714 bool IsInline = false, IsStaticDataMember = false, IsQualifiedFriend = false;
5715 bool IsMicrosoft = S.Context.getTargetInfo().getCXXABI().isMicrosoft();
5716 if (const auto *VD = dyn_cast<VarDecl>(NewDecl)) {
5717 // Ignore static data because out-of-line definitions are diagnosed
5719 IsStaticDataMember = VD->isStaticDataMember();
5720 IsDefinition = VD->isThisDeclarationADefinition(S.Context) !=
5721 VarDecl::DeclarationOnly;
5722 } else if (const auto *FD = dyn_cast<FunctionDecl>(NewDecl)) {
5723 IsInline = FD->isInlined();
5724 IsQualifiedFriend = FD->getQualifier() &&
5725 FD->getFriendObjectKind() == Decl::FOK_Declared;
5728 if (OldImportAttr && !HasNewAttr && !IsInline && !IsStaticDataMember &&
5729 !NewDecl->isLocalExternDecl() && !IsQualifiedFriend) {
5730 if (IsMicrosoft && IsDefinition) {
5731 S.Diag(NewDecl->getLocation(),
5732 diag::warn_redeclaration_without_import_attribute)
5734 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5735 NewDecl->dropAttr<DLLImportAttr>();
5736 NewDecl->addAttr(::new (S.Context) DLLExportAttr(
5737 NewImportAttr->getRange(), S.Context,
5738 NewImportAttr->getSpellingListIndex()));
5740 S.Diag(NewDecl->getLocation(),
5741 diag::warn_redeclaration_without_attribute_prev_attribute_ignored)
5742 << NewDecl << OldImportAttr;
5743 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5744 S.Diag(OldImportAttr->getLocation(), diag::note_previous_attribute);
5745 OldDecl->dropAttr<DLLImportAttr>();
5746 NewDecl->dropAttr<DLLImportAttr>();
5748 } else if (IsInline && OldImportAttr && !IsMicrosoft) {
5749 // In MinGW, seeing a function declared inline drops the dllimport attribute.
5750 OldDecl->dropAttr<DLLImportAttr>();
5751 NewDecl->dropAttr<DLLImportAttr>();
5752 S.Diag(NewDecl->getLocation(),
5753 diag::warn_dllimport_dropped_from_inline_function)
5754 << NewDecl << OldImportAttr;
5758 /// Given that we are within the definition of the given function,
5759 /// will that definition behave like C99's 'inline', where the
5760 /// definition is discarded except for optimization purposes?
5761 static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) {
5762 // Try to avoid calling GetGVALinkageForFunction.
5764 // All cases of this require the 'inline' keyword.
5765 if (!FD->isInlined()) return false;
5767 // This is only possible in C++ with the gnu_inline attribute.
5768 if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>())
5771 // Okay, go ahead and call the relatively-more-expensive function.
5772 return S.Context.GetGVALinkageForFunction(FD) == GVA_AvailableExternally;
5775 /// Determine whether a variable is extern "C" prior to attaching
5776 /// an initializer. We can't just call isExternC() here, because that
5777 /// will also compute and cache whether the declaration is externally
5778 /// visible, which might change when we attach the initializer.
5780 /// This can only be used if the declaration is known to not be a
5781 /// redeclaration of an internal linkage declaration.
5787 /// Attaching the initializer here makes this declaration not externally
5788 /// visible, because its type has internal linkage.
5790 /// FIXME: This is a hack.
5791 template<typename T>
5792 static bool isIncompleteDeclExternC(Sema &S, const T *D) {
5793 if (S.getLangOpts().CPlusPlus) {
5794 // In C++, the overloadable attribute negates the effects of extern "C".
5795 if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>())
5798 // So do CUDA's host/device attributes.
5799 if (S.getLangOpts().CUDA && (D->template hasAttr<CUDADeviceAttr>() ||
5800 D->template hasAttr<CUDAHostAttr>()))
5803 return D->isExternC();
5806 static bool shouldConsiderLinkage(const VarDecl *VD) {
5807 const DeclContext *DC = VD->getDeclContext()->getRedeclContext();
5808 if (DC->isFunctionOrMethod() || isa<OMPDeclareReductionDecl>(DC))
5809 return VD->hasExternalStorage();
5810 if (DC->isFileContext())
5814 llvm_unreachable("Unexpected context");
5817 static bool shouldConsiderLinkage(const FunctionDecl *FD) {
5818 const DeclContext *DC = FD->getDeclContext()->getRedeclContext();
5819 if (DC->isFileContext() || DC->isFunctionOrMethod() ||
5820 isa<OMPDeclareReductionDecl>(DC))
5824 llvm_unreachable("Unexpected context");
5827 static bool hasParsedAttr(Scope *S, const AttributeList *AttrList,
5828 AttributeList::Kind Kind) {
5829 for (const AttributeList *L = AttrList; L; L = L->getNext())
5830 if (L->getKind() == Kind)
5835 static bool hasParsedAttr(Scope *S, const Declarator &PD,
5836 AttributeList::Kind Kind) {
5837 // Check decl attributes on the DeclSpec.
5838 if (hasParsedAttr(S, PD.getDeclSpec().getAttributes().getList(), Kind))
5841 // Walk the declarator structure, checking decl attributes that were in a type
5842 // position to the decl itself.
5843 for (unsigned I = 0, E = PD.getNumTypeObjects(); I != E; ++I) {
5844 if (hasParsedAttr(S, PD.getTypeObject(I).getAttrs(), Kind))
5848 // Finally, check attributes on the decl itself.
5849 return hasParsedAttr(S, PD.getAttributes(), Kind);
5852 /// Adjust the \c DeclContext for a function or variable that might be a
5853 /// function-local external declaration.
5854 bool Sema::adjustContextForLocalExternDecl(DeclContext *&DC) {
5855 if (!DC->isFunctionOrMethod())
5858 // If this is a local extern function or variable declared within a function
5859 // template, don't add it into the enclosing namespace scope until it is
5860 // instantiated; it might have a dependent type right now.
5861 if (DC->isDependentContext())
5864 // C++11 [basic.link]p7:
5865 // When a block scope declaration of an entity with linkage is not found to
5866 // refer to some other declaration, then that entity is a member of the
5867 // innermost enclosing namespace.
5869 // Per C++11 [namespace.def]p6, the innermost enclosing namespace is a
5870 // semantically-enclosing namespace, not a lexically-enclosing one.
5871 while (!DC->isFileContext() && !isa<LinkageSpecDecl>(DC))
5872 DC = DC->getParent();
5876 /// \brief Returns true if given declaration has external C language linkage.
5877 static bool isDeclExternC(const Decl *D) {
5878 if (const auto *FD = dyn_cast<FunctionDecl>(D))
5879 return FD->isExternC();
5880 if (const auto *VD = dyn_cast<VarDecl>(D))
5881 return VD->isExternC();
5883 llvm_unreachable("Unknown type of decl!");
5886 NamedDecl *Sema::ActOnVariableDeclarator(
5887 Scope *S, Declarator &D, DeclContext *DC, TypeSourceInfo *TInfo,
5888 LookupResult &Previous, MultiTemplateParamsArg TemplateParamLists,
5889 bool &AddToScope, ArrayRef<BindingDecl *> Bindings) {
5890 QualType R = TInfo->getType();
5891 DeclarationName Name = GetNameForDeclarator(D).getName();
5893 IdentifierInfo *II = Name.getAsIdentifierInfo();
5895 if (D.isDecompositionDeclarator()) {
5897 // Take the name of the first declarator as our name for diagnostic
5899 auto &Decomp = D.getDecompositionDeclarator();
5900 if (!Decomp.bindings().empty()) {
5901 II = Decomp.bindings()[0].Name;
5905 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name)
5910 if (getLangOpts().OpenCL) {
5911 // OpenCL v2.0 s6.9.b - Image type can only be used as a function argument.
5912 // OpenCL v2.0 s6.13.16.1 - Pipe type can only be used as a function
5914 if (R->isImageType() || R->isPipeType()) {
5915 Diag(D.getIdentifierLoc(),
5916 diag::err_opencl_type_can_only_be_used_as_function_parameter)
5922 // OpenCL v1.2 s6.9.r:
5923 // The event type cannot be used to declare a program scope variable.
5924 // OpenCL v2.0 s6.9.q:
5925 // The clk_event_t and reserve_id_t types cannot be declared in program scope.
5926 if (NULL == S->getParent()) {
5927 if (R->isReserveIDT() || R->isClkEventT() || R->isEventT()) {
5928 Diag(D.getIdentifierLoc(),
5929 diag::err_invalid_type_for_program_scope_var) << R;
5935 // OpenCL v1.0 s6.8.a.3: Pointers to functions are not allowed.
5937 while (NR->isPointerType()) {
5938 if (NR->isFunctionPointerType()) {
5939 Diag(D.getIdentifierLoc(), diag::err_opencl_function_pointer_variable);
5943 NR = NR->getPointeeType();
5946 if (!getOpenCLOptions().isEnabled("cl_khr_fp16")) {
5947 // OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and
5948 // half array type (unless the cl_khr_fp16 extension is enabled).
5949 if (Context.getBaseElementType(R)->isHalfType()) {
5950 Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R;
5955 // OpenCL v1.2 s6.9.b p4:
5956 // The sampler type cannot be used with the __local and __global address
5957 // space qualifiers.
5958 if (R->isSamplerT() && (R.getAddressSpace() == LangAS::opencl_local ||
5959 R.getAddressSpace() == LangAS::opencl_global)) {
5960 Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace);
5963 // OpenCL v1.2 s6.9.r:
5964 // The event type cannot be used with the __local, __constant and __global
5965 // address space qualifiers.
5966 if (R->isEventT()) {
5967 if (R.getAddressSpace()) {
5968 Diag(D.getLocStart(), diag::err_event_t_addr_space_qual);
5974 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec();
5975 StorageClass SC = StorageClassSpecToVarDeclStorageClass(D.getDeclSpec());
5977 // dllimport globals without explicit storage class are treated as extern. We
5978 // have to change the storage class this early to get the right DeclContext.
5979 if (SC == SC_None && !DC->isRecord() &&
5980 hasParsedAttr(S, D, AttributeList::AT_DLLImport) &&
5981 !hasParsedAttr(S, D, AttributeList::AT_DLLExport))
5984 DeclContext *OriginalDC = DC;
5985 bool IsLocalExternDecl = SC == SC_Extern &&
5986 adjustContextForLocalExternDecl(DC);
5988 if (SCSpec == DeclSpec::SCS_mutable) {
5989 // mutable can only appear on non-static class members, so it's always
5991 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember);
5996 if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register &&
5997 !D.getAsmLabel() && !getSourceManager().isInSystemMacro(
5998 D.getDeclSpec().getStorageClassSpecLoc())) {
5999 // In C++11, the 'register' storage class specifier is deprecated.
6000 // Suppress the warning in system macros, it's used in macros in some
6001 // popular C system headers, such as in glibc's htonl() macro.
6002 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6003 getLangOpts().CPlusPlus1z ? diag::ext_register_storage_class
6004 : diag::warn_deprecated_register)
6005 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6008 DiagnoseFunctionSpecifiers(D.getDeclSpec());
6010 if (!DC->isRecord() && S->getFnParent() == nullptr) {
6011 // C99 6.9p2: The storage-class specifiers auto and register shall not
6012 // appear in the declaration specifiers in an external declaration.
6013 // Global Register+Asm is a GNU extension we support.
6014 if (SC == SC_Auto || (SC == SC_Register && !D.getAsmLabel())) {
6015 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope);
6020 bool IsExplicitSpecialization = false;
6021 bool IsVariableTemplateSpecialization = false;
6022 bool IsPartialSpecialization = false;
6023 bool IsVariableTemplate = false;
6024 VarDecl *NewVD = nullptr;
6025 VarTemplateDecl *NewTemplate = nullptr;
6026 TemplateParameterList *TemplateParams = nullptr;
6027 if (!getLangOpts().CPlusPlus) {
6028 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
6029 D.getIdentifierLoc(), II,
6032 if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
6033 ParsingInitForAutoVars.insert(NewVD);
6035 if (D.isInvalidType())
6036 NewVD->setInvalidDecl();
6038 bool Invalid = false;
6040 if (DC->isRecord() && !CurContext->isRecord()) {
6041 // This is an out-of-line definition of a static data member.
6046 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6047 diag::err_static_out_of_line)
6048 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6053 // [dcl.stc] p2: The auto or register specifiers shall be applied only
6054 // to names of variables declared in a block or to function parameters.
6055 // [dcl.stc] p6: The extern specifier cannot be used in the declaration
6058 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6059 diag::err_storage_class_for_static_member)
6060 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
6062 case SC_PrivateExtern:
6063 llvm_unreachable("C storage class in c++!");
6067 if (SC == SC_Static && CurContext->isRecord()) {
6068 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) {
6069 if (RD->isLocalClass())
6070 Diag(D.getIdentifierLoc(),
6071 diag::err_static_data_member_not_allowed_in_local_class)
6072 << Name << RD->getDeclName();
6074 // C++98 [class.union]p1: If a union contains a static data member,
6075 // the program is ill-formed. C++11 drops this restriction.
6077 Diag(D.getIdentifierLoc(),
6078 getLangOpts().CPlusPlus11
6079 ? diag::warn_cxx98_compat_static_data_member_in_union
6080 : diag::ext_static_data_member_in_union) << Name;
6081 // We conservatively disallow static data members in anonymous structs.
6082 else if (!RD->getDeclName())
6083 Diag(D.getIdentifierLoc(),
6084 diag::err_static_data_member_not_allowed_in_anon_struct)
6085 << Name << RD->isUnion();
6089 // Match up the template parameter lists with the scope specifier, then
6090 // determine whether we have a template or a template specialization.
6091 TemplateParams = MatchTemplateParametersToScopeSpecifier(
6092 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
6093 D.getCXXScopeSpec(),
6094 D.getName().getKind() == UnqualifiedId::IK_TemplateId
6095 ? D.getName().TemplateId
6098 /*never a friend*/ false, IsExplicitSpecialization, Invalid);
6100 if (TemplateParams) {
6101 if (!TemplateParams->size() &&
6102 D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
6103 // There is an extraneous 'template<>' for this variable. Complain
6104 // about it, but allow the declaration of the variable.
6105 Diag(TemplateParams->getTemplateLoc(),
6106 diag::err_template_variable_noparams)
6108 << SourceRange(TemplateParams->getTemplateLoc(),
6109 TemplateParams->getRAngleLoc());
6110 TemplateParams = nullptr;
6112 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
6113 // This is an explicit specialization or a partial specialization.
6114 // FIXME: Check that we can declare a specialization here.
6115 IsVariableTemplateSpecialization = true;
6116 IsPartialSpecialization = TemplateParams->size() > 0;
6117 } else { // if (TemplateParams->size() > 0)
6118 // This is a template declaration.
6119 IsVariableTemplate = true;
6121 // Check that we can declare a template here.
6122 if (CheckTemplateDeclScope(S, TemplateParams))
6125 // Only C++1y supports variable templates (N3651).
6126 Diag(D.getIdentifierLoc(),
6127 getLangOpts().CPlusPlus14
6128 ? diag::warn_cxx11_compat_variable_template
6129 : diag::ext_variable_template);
6134 (Invalid || D.getName().getKind() != UnqualifiedId::IK_TemplateId) &&
6135 "should have a 'template<>' for this decl");
6138 if (IsVariableTemplateSpecialization) {
6139 SourceLocation TemplateKWLoc =
6140 TemplateParamLists.size() > 0
6141 ? TemplateParamLists[0]->getTemplateLoc()
6143 DeclResult Res = ActOnVarTemplateSpecialization(
6144 S, D, TInfo, TemplateKWLoc, TemplateParams, SC,
6145 IsPartialSpecialization);
6146 if (Res.isInvalid())
6148 NewVD = cast<VarDecl>(Res.get());
6150 } else if (D.isDecompositionDeclarator()) {
6151 NewVD = DecompositionDecl::Create(Context, DC, D.getLocStart(),
6152 D.getIdentifierLoc(), R, TInfo, SC,
6155 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
6156 D.getIdentifierLoc(), II, R, TInfo, SC);
6158 // If this is supposed to be a variable template, create it as such.
6159 if (IsVariableTemplate) {
6161 VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name,
6162 TemplateParams, NewVD);
6163 NewVD->setDescribedVarTemplate(NewTemplate);
6166 // If this decl has an auto type in need of deduction, make a note of the
6167 // Decl so we can diagnose uses of it in its own initializer.
6168 if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
6169 ParsingInitForAutoVars.insert(NewVD);
6171 if (D.isInvalidType() || Invalid) {
6172 NewVD->setInvalidDecl();
6174 NewTemplate->setInvalidDecl();
6177 SetNestedNameSpecifier(NewVD, D);
6179 // If we have any template parameter lists that don't directly belong to
6180 // the variable (matching the scope specifier), store them.
6181 unsigned VDTemplateParamLists = TemplateParams ? 1 : 0;
6182 if (TemplateParamLists.size() > VDTemplateParamLists)
6183 NewVD->setTemplateParameterListsInfo(
6184 Context, TemplateParamLists.drop_back(VDTemplateParamLists));
6186 if (D.getDeclSpec().isConstexprSpecified()) {
6187 NewVD->setConstexpr(true);
6188 // C++1z [dcl.spec.constexpr]p1:
6189 // A static data member declared with the constexpr specifier is
6190 // implicitly an inline variable.
6191 if (NewVD->isStaticDataMember() && getLangOpts().CPlusPlus1z)
6192 NewVD->setImplicitlyInline();
6195 if (D.getDeclSpec().isConceptSpecified()) {
6196 if (VarTemplateDecl *VTD = NewVD->getDescribedVarTemplate())
6199 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
6200 // be declared with the thread_local, inline, friend, or constexpr
6201 // specifiers, [...]
6202 if (D.getDeclSpec().getThreadStorageClassSpec() == TSCS_thread_local) {
6203 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6204 diag::err_concept_decl_invalid_specifiers)
6206 NewVD->setInvalidDecl(true);
6209 if (D.getDeclSpec().isConstexprSpecified()) {
6210 Diag(D.getDeclSpec().getConstexprSpecLoc(),
6211 diag::err_concept_decl_invalid_specifiers)
6213 NewVD->setInvalidDecl(true);
6216 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
6217 // applied only to the definition of a function template or variable
6218 // template, declared in namespace scope.
6219 if (IsVariableTemplateSpecialization) {
6220 Diag(D.getDeclSpec().getConceptSpecLoc(),
6221 diag::err_concept_specified_specialization)
6222 << (IsPartialSpecialization ? 2 : 1);
6225 // C++ Concepts TS [dcl.spec.concept]p6: A variable concept has the
6226 // following restrictions:
6227 // - The declared type shall have the type bool.
6228 if (!Context.hasSameType(NewVD->getType(), Context.BoolTy) &&
6229 !NewVD->isInvalidDecl()) {
6230 Diag(D.getIdentifierLoc(), diag::err_variable_concept_bool_decl);
6231 NewVD->setInvalidDecl(true);
6236 if (D.getDeclSpec().isInlineSpecified()) {
6237 if (!getLangOpts().CPlusPlus) {
6238 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
6240 } else if (CurContext->isFunctionOrMethod()) {
6241 // 'inline' is not allowed on block scope variable declaration.
6242 Diag(D.getDeclSpec().getInlineSpecLoc(),
6243 diag::err_inline_declaration_block_scope) << Name
6244 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
6246 Diag(D.getDeclSpec().getInlineSpecLoc(),
6247 getLangOpts().CPlusPlus1z ? diag::warn_cxx14_compat_inline_variable
6248 : diag::ext_inline_variable);
6249 NewVD->setInlineSpecified();
6253 // Set the lexical context. If the declarator has a C++ scope specifier, the
6254 // lexical context will be different from the semantic context.
6255 NewVD->setLexicalDeclContext(CurContext);
6257 NewTemplate->setLexicalDeclContext(CurContext);
6259 if (IsLocalExternDecl) {
6260 if (D.isDecompositionDeclarator())
6261 for (auto *B : Bindings)
6262 B->setLocalExternDecl();
6264 NewVD->setLocalExternDecl();
6267 bool EmitTLSUnsupportedError = false;
6268 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) {
6269 // C++11 [dcl.stc]p4:
6270 // When thread_local is applied to a variable of block scope the
6271 // storage-class-specifier static is implied if it does not appear
6273 // Core issue: 'static' is not implied if the variable is declared
6275 if (NewVD->hasLocalStorage() &&
6276 (SCSpec != DeclSpec::SCS_unspecified ||
6277 TSCS != DeclSpec::TSCS_thread_local ||
6278 !DC->isFunctionOrMethod()))
6279 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6280 diag::err_thread_non_global)
6281 << DeclSpec::getSpecifierName(TSCS);
6282 else if (!Context.getTargetInfo().isTLSSupported()) {
6283 if (getLangOpts().CUDA) {
6284 // Postpone error emission until we've collected attributes required to
6285 // figure out whether it's a host or device variable and whether the
6286 // error should be ignored.
6287 EmitTLSUnsupportedError = true;
6288 // We still need to mark the variable as TLS so it shows up in AST with
6289 // proper storage class for other tools to use even if we're not going
6290 // to emit any code for it.
6291 NewVD->setTSCSpec(TSCS);
6293 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6294 diag::err_thread_unsupported);
6296 NewVD->setTSCSpec(TSCS);
6300 // An inline definition of a function with external linkage shall
6301 // not contain a definition of a modifiable object with static or
6302 // thread storage duration...
6303 // We only apply this when the function is required to be defined
6304 // elsewhere, i.e. when the function is not 'extern inline'. Note
6305 // that a local variable with thread storage duration still has to
6306 // be marked 'static'. Also note that it's possible to get these
6307 // semantics in C++ using __attribute__((gnu_inline)).
6308 if (SC == SC_Static && S->getFnParent() != nullptr &&
6309 !NewVD->getType().isConstQualified()) {
6310 FunctionDecl *CurFD = getCurFunctionDecl();
6311 if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) {
6312 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6313 diag::warn_static_local_in_extern_inline);
6314 MaybeSuggestAddingStaticToDecl(CurFD);
6318 if (D.getDeclSpec().isModulePrivateSpecified()) {
6319 if (IsVariableTemplateSpecialization)
6320 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6321 << (IsPartialSpecialization ? 1 : 0)
6322 << FixItHint::CreateRemoval(
6323 D.getDeclSpec().getModulePrivateSpecLoc());
6324 else if (IsExplicitSpecialization)
6325 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
6327 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6328 else if (NewVD->hasLocalStorage())
6329 Diag(NewVD->getLocation(), diag::err_module_private_local)
6330 << 0 << NewVD->getDeclName()
6331 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
6332 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
6334 NewVD->setModulePrivate();
6336 NewTemplate->setModulePrivate();
6337 for (auto *B : Bindings)
6338 B->setModulePrivate();
6342 // Handle attributes prior to checking for duplicates in MergeVarDecl
6343 ProcessDeclAttributes(S, NewVD, D);
6345 if (getLangOpts().CUDA) {
6346 if (EmitTLSUnsupportedError && DeclAttrsMatchCUDAMode(getLangOpts(), NewVD))
6347 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6348 diag::err_thread_unsupported);
6349 // CUDA B.2.5: "__shared__ and __constant__ variables have implied static
6350 // storage [duration]."
6351 if (SC == SC_None && S->getFnParent() != nullptr &&
6352 (NewVD->hasAttr<CUDASharedAttr>() ||
6353 NewVD->hasAttr<CUDAConstantAttr>())) {
6354 NewVD->setStorageClass(SC_Static);
6358 // Ensure that dllimport globals without explicit storage class are treated as
6359 // extern. The storage class is set above using parsed attributes. Now we can
6360 // check the VarDecl itself.
6361 assert(!NewVD->hasAttr<DLLImportAttr>() ||
6362 NewVD->getAttr<DLLImportAttr>()->isInherited() ||
6363 NewVD->isStaticDataMember() || NewVD->getStorageClass() != SC_None);
6365 // In auto-retain/release, infer strong retension for variables of
6367 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD))
6368 NewVD->setInvalidDecl();
6370 // Handle GNU asm-label extension (encoded as an attribute).
6371 if (Expr *E = (Expr*)D.getAsmLabel()) {
6372 // The parser guarantees this is a string.
6373 StringLiteral *SE = cast<StringLiteral>(E);
6374 StringRef Label = SE->getString();
6375 if (S->getFnParent() != nullptr) {
6379 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label;
6382 // Local Named register
6383 if (!Context.getTargetInfo().isValidGCCRegisterName(Label) &&
6384 DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl()))
6385 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6389 case SC_PrivateExtern:
6392 } else if (SC == SC_Register) {
6393 // Global Named register
6394 if (DeclAttrsMatchCUDAMode(getLangOpts(), NewVD)) {
6395 const auto &TI = Context.getTargetInfo();
6396 bool HasSizeMismatch;
6398 if (!TI.isValidGCCRegisterName(Label))
6399 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
6400 else if (!TI.validateGlobalRegisterVariable(Label,
6401 Context.getTypeSize(R),
6403 Diag(E->getExprLoc(), diag::err_asm_invalid_global_var_reg) << Label;
6404 else if (HasSizeMismatch)
6405 Diag(E->getExprLoc(), diag::err_asm_register_size_mismatch) << Label;
6408 if (!R->isIntegralType(Context) && !R->isPointerType()) {
6409 Diag(D.getLocStart(), diag::err_asm_bad_register_type);
6410 NewVD->setInvalidDecl(true);
6414 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0),
6415 Context, Label, 0));
6416 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
6417 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
6418 ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier());
6419 if (I != ExtnameUndeclaredIdentifiers.end()) {
6420 if (isDeclExternC(NewVD)) {
6421 NewVD->addAttr(I->second);
6422 ExtnameUndeclaredIdentifiers.erase(I);
6424 Diag(NewVD->getLocation(), diag::warn_redefine_extname_not_applied)
6425 << /*Variable*/1 << NewVD;
6429 // Find the shadowed declaration before filtering for scope.
6430 NamedDecl *ShadowedDecl = D.getCXXScopeSpec().isEmpty()
6431 ? getShadowedDeclaration(NewVD, Previous)
6434 // Don't consider existing declarations that are in a different
6435 // scope and are out-of-semantic-context declarations (if the new
6436 // declaration has linkage).
6437 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewVD),
6438 D.getCXXScopeSpec().isNotEmpty() ||
6439 IsExplicitSpecialization ||
6440 IsVariableTemplateSpecialization);
6442 // Check whether the previous declaration is in the same block scope. This
6443 // affects whether we merge types with it, per C++11 [dcl.array]p3.
6444 if (getLangOpts().CPlusPlus &&
6445 NewVD->isLocalVarDecl() && NewVD->hasExternalStorage())
6446 NewVD->setPreviousDeclInSameBlockScope(
6447 Previous.isSingleResult() && !Previous.isShadowed() &&
6448 isDeclInScope(Previous.getFoundDecl(), OriginalDC, S, false));
6450 if (!getLangOpts().CPlusPlus) {
6451 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6453 // If this is an explicit specialization of a static data member, check it.
6454 if (IsExplicitSpecialization && !NewVD->isInvalidDecl() &&
6455 CheckMemberSpecialization(NewVD, Previous))
6456 NewVD->setInvalidDecl();
6458 // Merge the decl with the existing one if appropriate.
6459 if (!Previous.empty()) {
6460 if (Previous.isSingleResult() &&
6461 isa<FieldDecl>(Previous.getFoundDecl()) &&
6462 D.getCXXScopeSpec().isSet()) {
6463 // The user tried to define a non-static data member
6464 // out-of-line (C++ [dcl.meaning]p1).
6465 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line)
6466 << D.getCXXScopeSpec().getRange();
6468 NewVD->setInvalidDecl();
6470 } else if (D.getCXXScopeSpec().isSet()) {
6471 // No previous declaration in the qualifying scope.
6472 Diag(D.getIdentifierLoc(), diag::err_no_member)
6473 << Name << computeDeclContext(D.getCXXScopeSpec(), true)
6474 << D.getCXXScopeSpec().getRange();
6475 NewVD->setInvalidDecl();
6478 if (!IsVariableTemplateSpecialization)
6479 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
6481 // C++ Concepts TS [dcl.spec.concept]p7: A program shall not declare [...]
6482 // an explicit specialization (14.8.3) or a partial specialization of a
6483 // concept definition.
6484 if (IsVariableTemplateSpecialization &&
6485 !D.getDeclSpec().isConceptSpecified() && !Previous.empty() &&
6486 Previous.isSingleResult()) {
6487 NamedDecl *PreviousDecl = Previous.getFoundDecl();
6488 if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(PreviousDecl)) {
6489 if (VarTmpl->isConcept()) {
6490 Diag(NewVD->getLocation(), diag::err_concept_specialized)
6492 << (IsPartialSpecialization ? 2 /*partially specialized*/
6493 : 1 /*explicitly specialized*/);
6494 Diag(VarTmpl->getLocation(), diag::note_previous_declaration);
6495 NewVD->setInvalidDecl();
6501 VarTemplateDecl *PrevVarTemplate =
6502 NewVD->getPreviousDecl()
6503 ? NewVD->getPreviousDecl()->getDescribedVarTemplate()
6506 // Check the template parameter list of this declaration, possibly
6507 // merging in the template parameter list from the previous variable
6508 // template declaration.
6509 if (CheckTemplateParameterList(
6511 PrevVarTemplate ? PrevVarTemplate->getTemplateParameters()
6513 (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() &&
6514 DC->isDependentContext())
6515 ? TPC_ClassTemplateMember
6517 NewVD->setInvalidDecl();
6519 // If we are providing an explicit specialization of a static variable
6520 // template, make a note of that.
6521 if (PrevVarTemplate &&
6522 PrevVarTemplate->getInstantiatedFromMemberTemplate())
6523 PrevVarTemplate->setMemberSpecialization();
6527 // Diagnose shadowed variables iff this isn't a redeclaration.
6528 if (ShadowedDecl && !D.isRedeclaration())
6529 CheckShadow(NewVD, ShadowedDecl, Previous);
6531 ProcessPragmaWeak(S, NewVD);
6533 // If this is the first declaration of an extern C variable, update
6534 // the map of such variables.
6535 if (NewVD->isFirstDecl() && !NewVD->isInvalidDecl() &&
6536 isIncompleteDeclExternC(*this, NewVD))
6537 RegisterLocallyScopedExternCDecl(NewVD, S);
6539 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
6540 Decl *ManglingContextDecl;
6541 if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(
6542 NewVD->getDeclContext(), ManglingContextDecl)) {
6543 Context.setManglingNumber(
6544 NewVD, MCtx->getManglingNumber(
6545 NewVD, getMSManglingNumber(getLangOpts(), S)));
6546 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
6550 // Special handling of variable named 'main'.
6551 if (Name.getAsIdentifierInfo() && Name.getAsIdentifierInfo()->isStr("main") &&
6552 NewVD->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
6553 !getLangOpts().Freestanding && !NewVD->getDescribedVarTemplate()) {
6555 // C++ [basic.start.main]p3
6556 // A program that declares a variable main at global scope is ill-formed.
6557 if (getLangOpts().CPlusPlus)
6558 Diag(D.getLocStart(), diag::err_main_global_variable);
6560 // In C, and external-linkage variable named main results in undefined
6562 else if (NewVD->hasExternalFormalLinkage())
6563 Diag(D.getLocStart(), diag::warn_main_redefined);
6566 if (D.isRedeclaration() && !Previous.empty()) {
6567 checkDLLAttributeRedeclaration(
6568 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewVD,
6569 IsExplicitSpecialization, D.isFunctionDefinition());
6573 if (NewVD->isInvalidDecl())
6574 NewTemplate->setInvalidDecl();
6575 ActOnDocumentableDecl(NewTemplate);
6582 /// Enum describing the %select options in diag::warn_decl_shadow.
6583 enum ShadowedDeclKind { SDK_Local, SDK_Global, SDK_StaticMember, SDK_Field };
6585 /// Determine what kind of declaration we're shadowing.
6586 static ShadowedDeclKind computeShadowedDeclKind(const NamedDecl *ShadowedDecl,
6587 const DeclContext *OldDC) {
6588 if (isa<RecordDecl>(OldDC))
6589 return isa<FieldDecl>(ShadowedDecl) ? SDK_Field : SDK_StaticMember;
6590 return OldDC->isFileContext() ? SDK_Global : SDK_Local;
6593 /// Return the location of the capture if the given lambda captures the given
6594 /// variable \p VD, or an invalid source location otherwise.
6595 static SourceLocation getCaptureLocation(const LambdaScopeInfo *LSI,
6596 const VarDecl *VD) {
6597 for (const LambdaScopeInfo::Capture &Capture : LSI->Captures) {
6598 if (Capture.isVariableCapture() && Capture.getVariable() == VD)
6599 return Capture.getLocation();
6601 return SourceLocation();
6604 /// \brief Return the declaration shadowed by the given variable \p D, or null
6605 /// if it doesn't shadow any declaration or shadowing warnings are disabled.
6606 NamedDecl *Sema::getShadowedDeclaration(const VarDecl *D,
6607 const LookupResult &R) {
6608 // Return if warning is ignored.
6609 if (Diags.isIgnored(diag::warn_decl_shadow, R.getNameLoc()))
6612 // Don't diagnose declarations at file scope.
6613 if (D->hasGlobalStorage())
6616 // Only diagnose if we're shadowing an unambiguous field or variable.
6617 if (R.getResultKind() != LookupResult::Found)
6620 NamedDecl *ShadowedDecl = R.getFoundDecl();
6621 return isa<VarDecl>(ShadowedDecl) || isa<FieldDecl>(ShadowedDecl)
6626 /// \brief Diagnose variable or built-in function shadowing. Implements
6629 /// This method is called whenever a VarDecl is added to a "useful"
6632 /// \param ShadowedDecl the declaration that is shadowed by the given variable
6633 /// \param R the lookup of the name
6635 void Sema::CheckShadow(VarDecl *D, NamedDecl *ShadowedDecl,
6636 const LookupResult &R) {
6637 DeclContext *NewDC = D->getDeclContext();
6639 if (FieldDecl *FD = dyn_cast<FieldDecl>(ShadowedDecl)) {
6640 // Fields are not shadowed by variables in C++ static methods.
6641 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC))
6645 // Fields shadowed by constructor parameters are a special case. Usually
6646 // the constructor initializes the field with the parameter.
6647 if (isa<CXXConstructorDecl>(NewDC) && isa<ParmVarDecl>(D)) {
6648 // Remember that this was shadowed so we can either warn about its
6649 // modification or its existence depending on warning settings.
6650 D = D->getCanonicalDecl();
6651 ShadowingDecls.insert({D, FD});
6656 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl))
6657 if (shadowedVar->isExternC()) {
6658 // For shadowing external vars, make sure that we point to the global
6659 // declaration, not a locally scoped extern declaration.
6660 for (auto I : shadowedVar->redecls())
6661 if (I->isFileVarDecl()) {
6667 DeclContext *OldDC = ShadowedDecl->getDeclContext();
6669 unsigned WarningDiag = diag::warn_decl_shadow;
6670 SourceLocation CaptureLoc;
6671 if (isa<VarDecl>(ShadowedDecl) && NewDC && isa<CXXMethodDecl>(NewDC)) {
6672 if (const auto *RD = dyn_cast<CXXRecordDecl>(NewDC->getParent())) {
6673 if (RD->isLambda() && OldDC->Encloses(NewDC->getLexicalParent())) {
6674 if (RD->getLambdaCaptureDefault() == LCD_None) {
6675 // Try to avoid warnings for lambdas with an explicit capture list.
6676 const auto *LSI = cast<LambdaScopeInfo>(getCurFunction());
6677 // Warn only when the lambda captures the shadowed decl explicitly.
6678 CaptureLoc = getCaptureLocation(LSI, cast<VarDecl>(ShadowedDecl));
6679 if (CaptureLoc.isInvalid())
6680 WarningDiag = diag::warn_decl_shadow_uncaptured_local;
6682 // Remember that this was shadowed so we can avoid the warning if the
6683 // shadowed decl isn't captured and the warning settings allow it.
6684 cast<LambdaScopeInfo>(getCurFunction())
6685 ->ShadowingDecls.push_back({D, cast<VarDecl>(ShadowedDecl)});
6692 // Only warn about certain kinds of shadowing for class members.
6693 if (NewDC && NewDC->isRecord()) {
6694 // In particular, don't warn about shadowing non-class members.
6695 if (!OldDC->isRecord())
6698 // TODO: should we warn about static data members shadowing
6699 // static data members from base classes?
6701 // TODO: don't diagnose for inaccessible shadowed members.
6702 // This is hard to do perfectly because we might friend the
6703 // shadowing context, but that's just a false negative.
6707 DeclarationName Name = R.getLookupName();
6709 // Emit warning and note.
6710 if (getSourceManager().isInSystemMacro(R.getNameLoc()))
6712 ShadowedDeclKind Kind = computeShadowedDeclKind(ShadowedDecl, OldDC);
6713 Diag(R.getNameLoc(), WarningDiag) << Name << Kind << OldDC;
6714 if (!CaptureLoc.isInvalid())
6715 Diag(CaptureLoc, diag::note_var_explicitly_captured_here)
6716 << Name << /*explicitly*/ 1;
6717 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6720 /// Diagnose shadowing for variables shadowed in the lambda record \p LambdaRD
6721 /// when these variables are captured by the lambda.
6722 void Sema::DiagnoseShadowingLambdaDecls(const LambdaScopeInfo *LSI) {
6723 for (const auto &Shadow : LSI->ShadowingDecls) {
6724 const VarDecl *ShadowedDecl = Shadow.ShadowedDecl;
6725 // Try to avoid the warning when the shadowed decl isn't captured.
6726 SourceLocation CaptureLoc = getCaptureLocation(LSI, ShadowedDecl);
6727 const DeclContext *OldDC = ShadowedDecl->getDeclContext();
6728 Diag(Shadow.VD->getLocation(), CaptureLoc.isInvalid()
6729 ? diag::warn_decl_shadow_uncaptured_local
6730 : diag::warn_decl_shadow)
6731 << Shadow.VD->getDeclName()
6732 << computeShadowedDeclKind(ShadowedDecl, OldDC) << OldDC;
6733 if (!CaptureLoc.isInvalid())
6734 Diag(CaptureLoc, diag::note_var_explicitly_captured_here)
6735 << Shadow.VD->getDeclName() << /*explicitly*/ 0;
6736 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6740 /// \brief Check -Wshadow without the advantage of a previous lookup.
6741 void Sema::CheckShadow(Scope *S, VarDecl *D) {
6742 if (Diags.isIgnored(diag::warn_decl_shadow, D->getLocation()))
6745 LookupResult R(*this, D->getDeclName(), D->getLocation(),
6746 Sema::LookupOrdinaryName, Sema::ForRedeclaration);
6748 if (NamedDecl *ShadowedDecl = getShadowedDeclaration(D, R))
6749 CheckShadow(D, ShadowedDecl, R);
6752 /// Check if 'E', which is an expression that is about to be modified, refers
6753 /// to a constructor parameter that shadows a field.
6754 void Sema::CheckShadowingDeclModification(Expr *E, SourceLocation Loc) {
6755 // Quickly ignore expressions that can't be shadowing ctor parameters.
6756 if (!getLangOpts().CPlusPlus || ShadowingDecls.empty())
6758 E = E->IgnoreParenImpCasts();
6759 auto *DRE = dyn_cast<DeclRefExpr>(E);
6762 const NamedDecl *D = cast<NamedDecl>(DRE->getDecl()->getCanonicalDecl());
6763 auto I = ShadowingDecls.find(D);
6764 if (I == ShadowingDecls.end())
6766 const NamedDecl *ShadowedDecl = I->second;
6767 const DeclContext *OldDC = ShadowedDecl->getDeclContext();
6768 Diag(Loc, diag::warn_modifying_shadowing_decl) << D << OldDC;
6769 Diag(D->getLocation(), diag::note_var_declared_here) << D;
6770 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
6772 // Avoid issuing multiple warnings about the same decl.
6773 ShadowingDecls.erase(I);
6776 /// Check for conflict between this global or extern "C" declaration and
6777 /// previous global or extern "C" declarations. This is only used in C++.
6778 template<typename T>
6779 static bool checkGlobalOrExternCConflict(
6780 Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) {
6781 assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\"");
6782 NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName());
6784 if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) {
6785 // The common case: this global doesn't conflict with any extern "C"
6791 if (!IsGlobal || isIncompleteDeclExternC(S, ND)) {
6792 // Both the old and new declarations have C language linkage. This is a
6795 Previous.addDecl(Prev);
6799 // This is a global, non-extern "C" declaration, and there is a previous
6800 // non-global extern "C" declaration. Diagnose if this is a variable
6802 if (!isa<VarDecl>(ND))
6805 // The declaration is extern "C". Check for any declaration in the
6806 // translation unit which might conflict.
6808 // We have already performed the lookup into the translation unit.
6810 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6812 if (isa<VarDecl>(*I)) {
6818 DeclContext::lookup_result R =
6819 S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName());
6820 for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end();
6822 if (isa<VarDecl>(*I)) {
6826 // FIXME: If we have any other entity with this name in global scope,
6827 // the declaration is ill-formed, but that is a defect: it breaks the
6828 // 'stat' hack, for instance. Only variables can have mangled name
6829 // clashes with extern "C" declarations, so only they deserve a
6838 // Use the first declaration's location to ensure we point at something which
6839 // is lexically inside an extern "C" linkage-spec.
6840 assert(Prev && "should have found a previous declaration to diagnose");
6841 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev))
6842 Prev = FD->getFirstDecl();
6844 Prev = cast<VarDecl>(Prev)->getFirstDecl();
6846 S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict)
6848 S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict)
6853 /// Apply special rules for handling extern "C" declarations. Returns \c true
6854 /// if we have found that this is a redeclaration of some prior entity.
6856 /// Per C++ [dcl.link]p6:
6857 /// Two declarations [for a function or variable] with C language linkage
6858 /// with the same name that appear in different scopes refer to the same
6859 /// [entity]. An entity with C language linkage shall not be declared with
6860 /// the same name as an entity in global scope.
6861 template<typename T>
6862 static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND,
6863 LookupResult &Previous) {
6864 if (!S.getLangOpts().CPlusPlus) {
6865 // In C, when declaring a global variable, look for a corresponding 'extern'
6866 // variable declared in function scope. We don't need this in C++, because
6867 // we find local extern decls in the surrounding file-scope DeclContext.
6868 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
6869 if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) {
6871 Previous.addDecl(Prev);
6878 // A declaration in the translation unit can conflict with an extern "C"
6880 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit())
6881 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous);
6883 // An extern "C" declaration can conflict with a declaration in the
6884 // translation unit or can be a redeclaration of an extern "C" declaration
6885 // in another scope.
6886 if (isIncompleteDeclExternC(S,ND))
6887 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous);
6889 // Neither global nor extern "C": nothing to do.
6893 void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
6894 // If the decl is already known invalid, don't check it.
6895 if (NewVD->isInvalidDecl())
6898 TypeSourceInfo *TInfo = NewVD->getTypeSourceInfo();
6899 QualType T = TInfo->getType();
6901 // Defer checking an 'auto' type until its initializer is attached.
6902 if (T->isUndeducedType())
6905 if (NewVD->hasAttrs())
6906 CheckAlignasUnderalignment(NewVD);
6908 if (T->isObjCObjectType()) {
6909 Diag(NewVD->getLocation(), diag::err_statically_allocated_object)
6910 << FixItHint::CreateInsertion(NewVD->getLocation(), "*");
6911 T = Context.getObjCObjectPointerType(T);
6915 // Emit an error if an address space was applied to decl with local storage.
6916 // This includes arrays of objects with address space qualifiers, but not
6917 // automatic variables that point to other address spaces.
6918 // ISO/IEC TR 18037 S5.1.2
6919 if (!getLangOpts().OpenCL
6920 && NewVD->hasLocalStorage() && T.getAddressSpace() != 0) {
6921 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl);
6922 NewVD->setInvalidDecl();
6926 // OpenCL v1.2 s6.8 - The static qualifier is valid only in program
6928 if (getLangOpts().OpenCLVersion == 120 &&
6929 !getOpenCLOptions().isEnabled("cl_clang_storage_class_specifiers") &&
6930 NewVD->isStaticLocal()) {
6931 Diag(NewVD->getLocation(), diag::err_static_function_scope);
6932 NewVD->setInvalidDecl();
6936 if (getLangOpts().OpenCL) {
6937 // OpenCL v2.0 s6.12.5 - The __block storage type is not supported.
6938 if (NewVD->hasAttr<BlocksAttr>()) {
6939 Diag(NewVD->getLocation(), diag::err_opencl_block_storage_type);
6943 if (T->isBlockPointerType()) {
6944 // OpenCL v2.0 s6.12.5 - Any block declaration must be const qualified and
6945 // can't use 'extern' storage class.
6946 if (!T.isConstQualified()) {
6947 Diag(NewVD->getLocation(), diag::err_opencl_invalid_block_declaration)
6949 NewVD->setInvalidDecl();
6952 if (NewVD->hasExternalStorage()) {
6953 Diag(NewVD->getLocation(), diag::err_opencl_extern_block_declaration);
6954 NewVD->setInvalidDecl();
6958 // OpenCL v1.2 s6.5 - All program scope variables must be declared in the
6959 // __constant address space.
6960 // OpenCL v2.0 s6.5.1 - Variables defined at program scope and static
6961 // variables inside a function can also be declared in the global
6963 if (NewVD->isFileVarDecl() || NewVD->isStaticLocal() ||
6964 NewVD->hasExternalStorage()) {
6965 if (!T->isSamplerT() &&
6966 !(T.getAddressSpace() == LangAS::opencl_constant ||
6967 (T.getAddressSpace() == LangAS::opencl_global &&
6968 getLangOpts().OpenCLVersion == 200))) {
6969 int Scope = NewVD->isStaticLocal() | NewVD->hasExternalStorage() << 1;
6970 if (getLangOpts().OpenCLVersion == 200)
6971 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
6972 << Scope << "global or constant";
6974 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space)
6975 << Scope << "constant";
6976 NewVD->setInvalidDecl();
6980 if (T.getAddressSpace() == LangAS::opencl_global) {
6981 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
6982 << 1 /*is any function*/ << "global";
6983 NewVD->setInvalidDecl();
6986 // OpenCL v1.1 s6.5.2 and s6.5.3 no local or constant variables
6988 if (T.getAddressSpace() == LangAS::opencl_constant ||
6989 T.getAddressSpace() == LangAS::opencl_local) {
6990 FunctionDecl *FD = getCurFunctionDecl();
6991 if (FD && !FD->hasAttr<OpenCLKernelAttr>()) {
6992 if (T.getAddressSpace() == LangAS::opencl_constant)
6993 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
6994 << 0 /*non-kernel only*/ << "constant";
6996 Diag(NewVD->getLocation(), diag::err_opencl_function_variable)
6997 << 0 /*non-kernel only*/ << "local";
6998 NewVD->setInvalidDecl();
7005 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()
7006 && !NewVD->hasAttr<BlocksAttr>()) {
7007 if (getLangOpts().getGC() != LangOptions::NonGC)
7008 Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local);
7010 assert(!getLangOpts().ObjCAutoRefCount);
7011 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
7015 bool isVM = T->isVariablyModifiedType();
7016 if (isVM || NewVD->hasAttr<CleanupAttr>() ||
7017 NewVD->hasAttr<BlocksAttr>())
7018 getCurFunction()->setHasBranchProtectedScope();
7020 if ((isVM && NewVD->hasLinkage()) ||
7021 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) {
7022 bool SizeIsNegative;
7023 llvm::APSInt Oversized;
7024 TypeSourceInfo *FixedTInfo =
7025 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
7026 SizeIsNegative, Oversized);
7027 if (!FixedTInfo && T->isVariableArrayType()) {
7028 const VariableArrayType *VAT = Context.getAsVariableArrayType(T);
7029 // FIXME: This won't give the correct result for
7031 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange();
7033 if (NewVD->isFileVarDecl())
7034 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope)
7036 else if (NewVD->isStaticLocal())
7037 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage)
7040 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage)
7042 NewVD->setInvalidDecl();
7047 if (NewVD->isFileVarDecl())
7048 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope);
7050 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage);
7051 NewVD->setInvalidDecl();
7055 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size);
7056 NewVD->setType(FixedTInfo->getType());
7057 NewVD->setTypeSourceInfo(FixedTInfo);
7060 if (T->isVoidType()) {
7061 // C++98 [dcl.stc]p5: The extern specifier can be applied only to the names
7062 // of objects and functions.
7063 if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) {
7064 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type)
7066 NewVD->setInvalidDecl();
7071 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) {
7072 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal);
7073 NewVD->setInvalidDecl();
7077 if (isVM && NewVD->hasAttr<BlocksAttr>()) {
7078 Diag(NewVD->getLocation(), diag::err_block_on_vm);
7079 NewVD->setInvalidDecl();
7083 if (NewVD->isConstexpr() && !T->isDependentType() &&
7084 RequireLiteralType(NewVD->getLocation(), T,
7085 diag::err_constexpr_var_non_literal)) {
7086 NewVD->setInvalidDecl();
7091 /// \brief Perform semantic checking on a newly-created variable
7094 /// This routine performs all of the type-checking required for a
7095 /// variable declaration once it has been built. It is used both to
7096 /// check variables after they have been parsed and their declarators
7097 /// have been translated into a declaration, and to check variables
7098 /// that have been instantiated from a template.
7100 /// Sets NewVD->isInvalidDecl() if an error was encountered.
7102 /// Returns true if the variable declaration is a redeclaration.
7103 bool Sema::CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous) {
7104 CheckVariableDeclarationType(NewVD);
7106 // If the decl is already known invalid, don't check it.
7107 if (NewVD->isInvalidDecl())
7110 // If we did not find anything by this name, look for a non-visible
7111 // extern "C" declaration with the same name.
7112 if (Previous.empty() &&
7113 checkForConflictWithNonVisibleExternC(*this, NewVD, Previous))
7114 Previous.setShadowed();
7116 if (!Previous.empty()) {
7117 MergeVarDecl(NewVD, Previous);
7124 struct FindOverriddenMethod {
7126 CXXMethodDecl *Method;
7128 /// Member lookup function that determines whether a given C++
7129 /// method overrides a method in a base class, to be used with
7130 /// CXXRecordDecl::lookupInBases().
7131 bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
7132 RecordDecl *BaseRecord =
7133 Specifier->getType()->getAs<RecordType>()->getDecl();
7135 DeclarationName Name = Method->getDeclName();
7137 // FIXME: Do we care about other names here too?
7138 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7139 // We really want to find the base class destructor here.
7140 QualType T = S->Context.getTypeDeclType(BaseRecord);
7141 CanQualType CT = S->Context.getCanonicalType(T);
7143 Name = S->Context.DeclarationNames.getCXXDestructorName(CT);
7146 for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
7147 Path.Decls = Path.Decls.slice(1)) {
7148 NamedDecl *D = Path.Decls.front();
7149 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
7150 if (MD->isVirtual() && !S->IsOverload(Method, MD, false))
7159 enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted };
7160 } // end anonymous namespace
7162 /// \brief Report an error regarding overriding, along with any relevant
7163 /// overriden methods.
7165 /// \param DiagID the primary error to report.
7166 /// \param MD the overriding method.
7167 /// \param OEK which overrides to include as notes.
7168 static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD,
7169 OverrideErrorKind OEK = OEK_All) {
7170 S.Diag(MD->getLocation(), DiagID) << MD->getDeclName();
7171 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
7172 E = MD->end_overridden_methods();
7174 // This check (& the OEK parameter) could be replaced by a predicate, but
7175 // without lambdas that would be overkill. This is still nicer than writing
7176 // out the diag loop 3 times.
7177 if ((OEK == OEK_All) ||
7178 (OEK == OEK_NonDeleted && !(*I)->isDeleted()) ||
7179 (OEK == OEK_Deleted && (*I)->isDeleted()))
7180 S.Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
7184 /// AddOverriddenMethods - See if a method overrides any in the base classes,
7185 /// and if so, check that it's a valid override and remember it.
7186 bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) {
7187 // Look for methods in base classes that this method might override.
7189 FindOverriddenMethod FOM;
7192 bool hasDeletedOverridenMethods = false;
7193 bool hasNonDeletedOverridenMethods = false;
7194 bool AddedAny = false;
7195 if (DC->lookupInBases(FOM, Paths)) {
7196 for (auto *I : Paths.found_decls()) {
7197 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(I)) {
7198 MD->addOverriddenMethod(OldMD->getCanonicalDecl());
7199 if (!CheckOverridingFunctionReturnType(MD, OldMD) &&
7200 !CheckOverridingFunctionAttributes(MD, OldMD) &&
7201 !CheckOverridingFunctionExceptionSpec(MD, OldMD) &&
7202 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) {
7203 hasDeletedOverridenMethods |= OldMD->isDeleted();
7204 hasNonDeletedOverridenMethods |= !OldMD->isDeleted();
7211 if (hasDeletedOverridenMethods && !MD->isDeleted()) {
7212 ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted);
7214 if (hasNonDeletedOverridenMethods && MD->isDeleted()) {
7215 ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted);
7222 // Struct for holding all of the extra arguments needed by
7223 // DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator.
7224 struct ActOnFDArgs {
7227 MultiTemplateParamsArg TemplateParamLists;
7230 } // end anonymous namespace
7234 // Callback to only accept typo corrections that have a non-zero edit distance.
7235 // Also only accept corrections that have the same parent decl.
7236 class DifferentNameValidatorCCC : public CorrectionCandidateCallback {
7238 DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD,
7239 CXXRecordDecl *Parent)
7240 : Context(Context), OriginalFD(TypoFD),
7241 ExpectedParent(Parent ? Parent->getCanonicalDecl() : nullptr) {}
7243 bool ValidateCandidate(const TypoCorrection &candidate) override {
7244 if (candidate.getEditDistance() == 0)
7247 SmallVector<unsigned, 1> MismatchedParams;
7248 for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(),
7249 CDeclEnd = candidate.end();
7250 CDecl != CDeclEnd; ++CDecl) {
7251 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7253 if (FD && !FD->hasBody() &&
7254 hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) {
7255 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
7256 CXXRecordDecl *Parent = MD->getParent();
7257 if (Parent && Parent->getCanonicalDecl() == ExpectedParent)
7259 } else if (!ExpectedParent) {
7269 ASTContext &Context;
7270 FunctionDecl *OriginalFD;
7271 CXXRecordDecl *ExpectedParent;
7274 } // end anonymous namespace
7276 /// \brief Generate diagnostics for an invalid function redeclaration.
7278 /// This routine handles generating the diagnostic messages for an invalid
7279 /// function redeclaration, including finding possible similar declarations
7280 /// or performing typo correction if there are no previous declarations with
7283 /// Returns a NamedDecl iff typo correction was performed and substituting in
7284 /// the new declaration name does not cause new errors.
7285 static NamedDecl *DiagnoseInvalidRedeclaration(
7286 Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD,
7287 ActOnFDArgs &ExtraArgs, bool IsLocalFriend, Scope *S) {
7288 DeclarationName Name = NewFD->getDeclName();
7289 DeclContext *NewDC = NewFD->getDeclContext();
7290 SmallVector<unsigned, 1> MismatchedParams;
7291 SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches;
7292 TypoCorrection Correction;
7293 bool IsDefinition = ExtraArgs.D.isFunctionDefinition();
7294 unsigned DiagMsg = IsLocalFriend ? diag::err_no_matching_local_friend
7295 : diag::err_member_decl_does_not_match;
7296 LookupResult Prev(SemaRef, Name, NewFD->getLocation(),
7297 IsLocalFriend ? Sema::LookupLocalFriendName
7298 : Sema::LookupOrdinaryName,
7299 Sema::ForRedeclaration);
7301 NewFD->setInvalidDecl();
7303 SemaRef.LookupName(Prev, S);
7305 SemaRef.LookupQualifiedName(Prev, NewDC);
7306 assert(!Prev.isAmbiguous() &&
7307 "Cannot have an ambiguity in previous-declaration lookup");
7308 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
7309 if (!Prev.empty()) {
7310 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end();
7311 Func != FuncEnd; ++Func) {
7312 FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func);
7314 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7315 // Add 1 to the index so that 0 can mean the mismatch didn't
7316 // involve a parameter
7318 MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1;
7319 NearMatches.push_back(std::make_pair(FD, ParamNum));
7322 // If the qualified name lookup yielded nothing, try typo correction
7323 } else if ((Correction = SemaRef.CorrectTypo(
7324 Prev.getLookupNameInfo(), Prev.getLookupKind(), S,
7325 &ExtraArgs.D.getCXXScopeSpec(),
7326 llvm::make_unique<DifferentNameValidatorCCC>(
7327 SemaRef.Context, NewFD, MD ? MD->getParent() : nullptr),
7328 Sema::CTK_ErrorRecovery, IsLocalFriend ? nullptr : NewDC))) {
7329 // Set up everything for the call to ActOnFunctionDeclarator
7330 ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(),
7331 ExtraArgs.D.getIdentifierLoc());
7333 Previous.setLookupName(Correction.getCorrection());
7334 for (TypoCorrection::decl_iterator CDecl = Correction.begin(),
7335 CDeclEnd = Correction.end();
7336 CDecl != CDeclEnd; ++CDecl) {
7337 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
7338 if (FD && !FD->hasBody() &&
7339 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
7340 Previous.addDecl(FD);
7343 bool wasRedeclaration = ExtraArgs.D.isRedeclaration();
7346 // Retry building the function declaration with the new previous
7347 // declarations, and with errors suppressed.
7350 Sema::SFINAETrap Trap(SemaRef);
7352 // TODO: Refactor ActOnFunctionDeclarator so that we can call only the
7353 // pieces need to verify the typo-corrected C++ declaration and hopefully
7354 // eliminate the need for the parameter pack ExtraArgs.
7355 Result = SemaRef.ActOnFunctionDeclarator(
7356 ExtraArgs.S, ExtraArgs.D,
7357 Correction.getCorrectionDecl()->getDeclContext(),
7358 NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists,
7359 ExtraArgs.AddToScope);
7361 if (Trap.hasErrorOccurred())
7366 // Determine which correction we picked.
7367 Decl *Canonical = Result->getCanonicalDecl();
7368 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
7370 if ((*I)->getCanonicalDecl() == Canonical)
7371 Correction.setCorrectionDecl(*I);
7373 SemaRef.diagnoseTypo(
7375 SemaRef.PDiag(IsLocalFriend
7376 ? diag::err_no_matching_local_friend_suggest
7377 : diag::err_member_decl_does_not_match_suggest)
7378 << Name << NewDC << IsDefinition);
7382 // Pretend the typo correction never occurred
7383 ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(),
7384 ExtraArgs.D.getIdentifierLoc());
7385 ExtraArgs.D.setRedeclaration(wasRedeclaration);
7387 Previous.setLookupName(Name);
7390 SemaRef.Diag(NewFD->getLocation(), DiagMsg)
7391 << Name << NewDC << IsDefinition << NewFD->getLocation();
7393 bool NewFDisConst = false;
7394 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD))
7395 NewFDisConst = NewMD->isConst();
7397 for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator
7398 NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end();
7399 NearMatch != NearMatchEnd; ++NearMatch) {
7400 FunctionDecl *FD = NearMatch->first;
7401 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
7402 bool FDisConst = MD && MD->isConst();
7403 bool IsMember = MD || !IsLocalFriend;
7405 // FIXME: These notes are poorly worded for the local friend case.
7406 if (unsigned Idx = NearMatch->second) {
7407 ParmVarDecl *FDParam = FD->getParamDecl(Idx-1);
7408 SourceLocation Loc = FDParam->getTypeSpecStartLoc();
7409 if (Loc.isInvalid()) Loc = FD->getLocation();
7410 SemaRef.Diag(Loc, IsMember ? diag::note_member_def_close_param_match
7411 : diag::note_local_decl_close_param_match)
7412 << Idx << FDParam->getType()
7413 << NewFD->getParamDecl(Idx - 1)->getType();
7414 } else if (FDisConst != NewFDisConst) {
7415 SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match)
7416 << NewFDisConst << FD->getSourceRange().getEnd();
7418 SemaRef.Diag(FD->getLocation(),
7419 IsMember ? diag::note_member_def_close_match
7420 : diag::note_local_decl_close_match);
7425 static StorageClass getFunctionStorageClass(Sema &SemaRef, Declarator &D) {
7426 switch (D.getDeclSpec().getStorageClassSpec()) {
7427 default: llvm_unreachable("Unknown storage class!");
7428 case DeclSpec::SCS_auto:
7429 case DeclSpec::SCS_register:
7430 case DeclSpec::SCS_mutable:
7431 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7432 diag::err_typecheck_sclass_func);
7435 case DeclSpec::SCS_unspecified: break;
7436 case DeclSpec::SCS_extern:
7437 if (D.getDeclSpec().isExternInLinkageSpec())
7440 case DeclSpec::SCS_static: {
7441 if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) {
7443 // The declaration of an identifier for a function that has
7444 // block scope shall have no explicit storage-class specifier
7445 // other than extern
7446 // See also (C++ [dcl.stc]p4).
7447 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7448 diag::err_static_block_func);
7453 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
7456 // No explicit storage class has already been returned
7460 static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
7461 DeclContext *DC, QualType &R,
7462 TypeSourceInfo *TInfo,
7464 bool &IsVirtualOkay) {
7465 DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D);
7466 DeclarationName Name = NameInfo.getName();
7468 FunctionDecl *NewFD = nullptr;
7469 bool isInline = D.getDeclSpec().isInlineSpecified();
7471 if (!SemaRef.getLangOpts().CPlusPlus) {
7472 // Determine whether the function was written with a
7473 // prototype. This true when:
7474 // - there is a prototype in the declarator, or
7475 // - the type R of the function is some kind of typedef or other reference
7476 // to a type name (which eventually refers to a function type).
7478 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) ||
7479 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType());
7481 NewFD = FunctionDecl::Create(SemaRef.Context, DC,
7482 D.getLocStart(), NameInfo, R,
7483 TInfo, SC, isInline,
7484 HasPrototype, false);
7485 if (D.isInvalidType())
7486 NewFD->setInvalidDecl();
7491 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
7492 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
7494 // Check that the return type is not an abstract class type.
7495 // For record types, this is done by the AbstractClassUsageDiagnoser once
7496 // the class has been completely parsed.
7497 if (!DC->isRecord() &&
7498 SemaRef.RequireNonAbstractType(
7499 D.getIdentifierLoc(), R->getAs<FunctionType>()->getReturnType(),
7500 diag::err_abstract_type_in_decl, SemaRef.AbstractReturnType))
7503 if (Name.getNameKind() == DeclarationName::CXXConstructorName) {
7504 // This is a C++ constructor declaration.
7505 assert(DC->isRecord() &&
7506 "Constructors can only be declared in a member context");
7508 R = SemaRef.CheckConstructorDeclarator(D, R, SC);
7509 return CXXConstructorDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7510 D.getLocStart(), NameInfo,
7511 R, TInfo, isExplicit, isInline,
7512 /*isImplicitlyDeclared=*/false,
7515 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7516 // This is a C++ destructor declaration.
7517 if (DC->isRecord()) {
7518 R = SemaRef.CheckDestructorDeclarator(D, R, SC);
7519 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
7520 CXXDestructorDecl *NewDD = CXXDestructorDecl::Create(
7521 SemaRef.Context, Record,
7523 NameInfo, R, TInfo, isInline,
7524 /*isImplicitlyDeclared=*/false);
7526 // If the class is complete, then we now create the implicit exception
7527 // specification. If the class is incomplete or dependent, we can't do
7529 if (SemaRef.getLangOpts().CPlusPlus11 && !Record->isDependentType() &&
7530 Record->getDefinition() && !Record->isBeingDefined() &&
7531 R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) {
7532 SemaRef.AdjustDestructorExceptionSpec(Record, NewDD);
7535 IsVirtualOkay = true;
7539 SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member);
7542 // Create a FunctionDecl to satisfy the function definition parsing
7544 return FunctionDecl::Create(SemaRef.Context, DC,
7546 D.getIdentifierLoc(), Name, R, TInfo,
7548 /*hasPrototype=*/true, isConstexpr);
7551 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
7552 if (!DC->isRecord()) {
7553 SemaRef.Diag(D.getIdentifierLoc(),
7554 diag::err_conv_function_not_member);
7558 SemaRef.CheckConversionDeclarator(D, R, SC);
7559 IsVirtualOkay = true;
7560 return CXXConversionDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
7561 D.getLocStart(), NameInfo,
7562 R, TInfo, isInline, isExplicit,
7563 isConstexpr, SourceLocation());
7565 } else if (DC->isRecord()) {
7566 // If the name of the function is the same as the name of the record,
7567 // then this must be an invalid constructor that has a return type.
7568 // (The parser checks for a return type and makes the declarator a
7569 // constructor if it has no return type).
7570 if (Name.getAsIdentifierInfo() &&
7571 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){
7572 SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type)
7573 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
7574 << SourceRange(D.getIdentifierLoc());
7578 // This is a C++ method declaration.
7579 CXXMethodDecl *Ret = CXXMethodDecl::Create(SemaRef.Context,
7580 cast<CXXRecordDecl>(DC),
7581 D.getLocStart(), NameInfo, R,
7582 TInfo, SC, isInline,
7583 isConstexpr, SourceLocation());
7584 IsVirtualOkay = !Ret->isStatic();
7588 SemaRef.getLangOpts().CPlusPlus && D.getDeclSpec().isFriendSpecified();
7589 if (!isFriend && SemaRef.CurContext->isRecord())
7592 // Determine whether the function was written with a
7593 // prototype. This true when:
7594 // - we're in C++ (where every function has a prototype),
7595 return FunctionDecl::Create(SemaRef.Context, DC,
7597 NameInfo, R, TInfo, SC, isInline,
7598 true/*HasPrototype*/, isConstexpr);
7602 enum OpenCLParamType {
7606 InvalidAddrSpacePtrKernelParam,
7611 static OpenCLParamType getOpenCLKernelParameterType(Sema &S, QualType PT) {
7612 if (PT->isPointerType()) {
7613 QualType PointeeType = PT->getPointeeType();
7614 if (PointeeType->isPointerType())
7615 return PtrPtrKernelParam;
7616 if (PointeeType.getAddressSpace() == LangAS::opencl_generic ||
7617 PointeeType.getAddressSpace() == 0)
7618 return InvalidAddrSpacePtrKernelParam;
7619 return PtrKernelParam;
7622 // TODO: Forbid the other integer types (size_t, ptrdiff_t...) when they can
7623 // be used as builtin types.
7625 if (PT->isImageType())
7626 return PtrKernelParam;
7628 if (PT->isBooleanType())
7629 return InvalidKernelParam;
7632 return InvalidKernelParam;
7634 // OpenCL extension spec v1.2 s9.5:
7635 // This extension adds support for half scalar and vector types as built-in
7636 // types that can be used for arithmetic operations, conversions etc.
7637 if (!S.getOpenCLOptions().isEnabled("cl_khr_fp16") && PT->isHalfType())
7638 return InvalidKernelParam;
7640 if (PT->isRecordType())
7641 return RecordKernelParam;
7643 return ValidKernelParam;
7646 static void checkIsValidOpenCLKernelParameter(
7650 llvm::SmallPtrSetImpl<const Type *> &ValidTypes) {
7651 QualType PT = Param->getType();
7653 // Cache the valid types we encounter to avoid rechecking structs that are
7655 if (ValidTypes.count(PT.getTypePtr()))
7658 switch (getOpenCLKernelParameterType(S, PT)) {
7659 case PtrPtrKernelParam:
7660 // OpenCL v1.2 s6.9.a:
7661 // A kernel function argument cannot be declared as a
7662 // pointer to a pointer type.
7663 S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param);
7667 case InvalidAddrSpacePtrKernelParam:
7668 // OpenCL v1.0 s6.5:
7669 // __kernel function arguments declared to be a pointer of a type can point
7670 // to one of the following address spaces only : __global, __local or
7672 S.Diag(Param->getLocation(), diag::err_kernel_arg_address_space);
7676 // OpenCL v1.2 s6.9.k:
7677 // Arguments to kernel functions in a program cannot be declared with the
7678 // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and
7679 // uintptr_t or a struct and/or union that contain fields declared to be
7680 // one of these built-in scalar types.
7682 case InvalidKernelParam:
7683 // OpenCL v1.2 s6.8 n:
7684 // A kernel function argument cannot be declared
7686 // Do not diagnose half type since it is diagnosed as invalid argument
7687 // type for any function elsewhere.
7688 if (!PT->isHalfType())
7689 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7693 case PtrKernelParam:
7694 case ValidKernelParam:
7695 ValidTypes.insert(PT.getTypePtr());
7698 case RecordKernelParam:
7702 // Track nested structs we will inspect
7703 SmallVector<const Decl *, 4> VisitStack;
7705 // Track where we are in the nested structs. Items will migrate from
7706 // VisitStack to HistoryStack as we do the DFS for bad field.
7707 SmallVector<const FieldDecl *, 4> HistoryStack;
7708 HistoryStack.push_back(nullptr);
7710 const RecordDecl *PD = PT->castAs<RecordType>()->getDecl();
7711 VisitStack.push_back(PD);
7713 assert(VisitStack.back() && "First decl null?");
7716 const Decl *Next = VisitStack.pop_back_val();
7718 assert(!HistoryStack.empty());
7719 // Found a marker, we have gone up a level
7720 if (const FieldDecl *Hist = HistoryStack.pop_back_val())
7721 ValidTypes.insert(Hist->getType().getTypePtr());
7726 // Adds everything except the original parameter declaration (which is not a
7727 // field itself) to the history stack.
7728 const RecordDecl *RD;
7729 if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) {
7730 HistoryStack.push_back(Field);
7731 RD = Field->getType()->castAs<RecordType>()->getDecl();
7733 RD = cast<RecordDecl>(Next);
7736 // Add a null marker so we know when we've gone back up a level
7737 VisitStack.push_back(nullptr);
7739 for (const auto *FD : RD->fields()) {
7740 QualType QT = FD->getType();
7742 if (ValidTypes.count(QT.getTypePtr()))
7745 OpenCLParamType ParamType = getOpenCLKernelParameterType(S, QT);
7746 if (ParamType == ValidKernelParam)
7749 if (ParamType == RecordKernelParam) {
7750 VisitStack.push_back(FD);
7754 // OpenCL v1.2 s6.9.p:
7755 // Arguments to kernel functions that are declared to be a struct or union
7756 // do not allow OpenCL objects to be passed as elements of the struct or
7758 if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam ||
7759 ParamType == InvalidAddrSpacePtrKernelParam) {
7760 S.Diag(Param->getLocation(),
7761 diag::err_record_with_pointers_kernel_param)
7762 << PT->isUnionType()
7765 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
7768 S.Diag(PD->getLocation(), diag::note_within_field_of_type)
7769 << PD->getDeclName();
7771 // We have an error, now let's go back up through history and show where
7772 // the offending field came from
7773 for (ArrayRef<const FieldDecl *>::const_iterator
7774 I = HistoryStack.begin() + 1,
7775 E = HistoryStack.end();
7777 const FieldDecl *OuterField = *I;
7778 S.Diag(OuterField->getLocation(), diag::note_within_field_of_type)
7779 << OuterField->getType();
7782 S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here)
7783 << QT->isPointerType()
7788 } while (!VisitStack.empty());
7791 /// Find the DeclContext in which a tag is implicitly declared if we see an
7792 /// elaborated type specifier in the specified context, and lookup finds
7794 static DeclContext *getTagInjectionContext(DeclContext *DC) {
7795 while (!DC->isFileContext() && !DC->isFunctionOrMethod())
7796 DC = DC->getParent();
7800 /// Find the Scope in which a tag is implicitly declared if we see an
7801 /// elaborated type specifier in the specified context, and lookup finds
7803 static Scope *getTagInjectionScope(Scope *S, const LangOptions &LangOpts) {
7804 while (S->isClassScope() ||
7805 (LangOpts.CPlusPlus &&
7806 S->isFunctionPrototypeScope()) ||
7807 ((S->getFlags() & Scope::DeclScope) == 0) ||
7808 (S->getEntity() && S->getEntity()->isTransparentContext()))
7814 Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
7815 TypeSourceInfo *TInfo, LookupResult &Previous,
7816 MultiTemplateParamsArg TemplateParamLists,
7818 QualType R = TInfo->getType();
7820 assert(R.getTypePtr()->isFunctionType());
7822 // TODO: consider using NameInfo for diagnostic.
7823 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
7824 DeclarationName Name = NameInfo.getName();
7825 StorageClass SC = getFunctionStorageClass(*this, D);
7827 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
7828 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
7829 diag::err_invalid_thread)
7830 << DeclSpec::getSpecifierName(TSCS);
7832 if (D.isFirstDeclarationOfMember())
7833 adjustMemberFunctionCC(R, D.isStaticMember(), D.isCtorOrDtor(),
7834 D.getIdentifierLoc());
7836 bool isFriend = false;
7837 FunctionTemplateDecl *FunctionTemplate = nullptr;
7838 bool isExplicitSpecialization = false;
7839 bool isFunctionTemplateSpecialization = false;
7841 bool isDependentClassScopeExplicitSpecialization = false;
7842 bool HasExplicitTemplateArgs = false;
7843 TemplateArgumentListInfo TemplateArgs;
7845 bool isVirtualOkay = false;
7847 DeclContext *OriginalDC = DC;
7848 bool IsLocalExternDecl = adjustContextForLocalExternDecl(DC);
7850 FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC,
7852 if (!NewFD) return nullptr;
7854 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer())
7855 NewFD->setTopLevelDeclInObjCContainer();
7857 // Set the lexical context. If this is a function-scope declaration, or has a
7858 // C++ scope specifier, or is the object of a friend declaration, the lexical
7859 // context will be different from the semantic context.
7860 NewFD->setLexicalDeclContext(CurContext);
7862 if (IsLocalExternDecl)
7863 NewFD->setLocalExternDecl();
7865 if (getLangOpts().CPlusPlus) {
7866 bool isInline = D.getDeclSpec().isInlineSpecified();
7867 bool isVirtual = D.getDeclSpec().isVirtualSpecified();
7868 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
7869 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
7870 bool isConcept = D.getDeclSpec().isConceptSpecified();
7871 isFriend = D.getDeclSpec().isFriendSpecified();
7872 if (isFriend && !isInline && D.isFunctionDefinition()) {
7873 // C++ [class.friend]p5
7874 // A function can be defined in a friend declaration of a
7875 // class . . . . Such a function is implicitly inline.
7876 NewFD->setImplicitlyInline();
7879 // If this is a method defined in an __interface, and is not a constructor
7880 // or an overloaded operator, then set the pure flag (isVirtual will already
7882 if (const CXXRecordDecl *Parent =
7883 dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) {
7884 if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided())
7885 NewFD->setPure(true);
7887 // C++ [class.union]p2
7888 // A union can have member functions, but not virtual functions.
7889 if (isVirtual && Parent->isUnion())
7890 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_in_union);
7893 SetNestedNameSpecifier(NewFD, D);
7894 isExplicitSpecialization = false;
7895 isFunctionTemplateSpecialization = false;
7896 if (D.isInvalidType())
7897 NewFD->setInvalidDecl();
7899 // Match up the template parameter lists with the scope specifier, then
7900 // determine whether we have a template or a template specialization.
7901 bool Invalid = false;
7902 if (TemplateParameterList *TemplateParams =
7903 MatchTemplateParametersToScopeSpecifier(
7904 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
7905 D.getCXXScopeSpec(),
7906 D.getName().getKind() == UnqualifiedId::IK_TemplateId
7907 ? D.getName().TemplateId
7909 TemplateParamLists, isFriend, isExplicitSpecialization,
7911 if (TemplateParams->size() > 0) {
7912 // This is a function template
7914 // Check that we can declare a template here.
7915 if (CheckTemplateDeclScope(S, TemplateParams))
7916 NewFD->setInvalidDecl();
7918 // A destructor cannot be a template.
7919 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7920 Diag(NewFD->getLocation(), diag::err_destructor_template);
7921 NewFD->setInvalidDecl();
7924 // If we're adding a template to a dependent context, we may need to
7925 // rebuilding some of the types used within the template parameter list,
7926 // now that we know what the current instantiation is.
7927 if (DC->isDependentContext()) {
7928 ContextRAII SavedContext(*this, DC);
7929 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
7933 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC,
7934 NewFD->getLocation(),
7935 Name, TemplateParams,
7937 FunctionTemplate->setLexicalDeclContext(CurContext);
7938 NewFD->setDescribedFunctionTemplate(FunctionTemplate);
7940 // For source fidelity, store the other template param lists.
7941 if (TemplateParamLists.size() > 1) {
7942 NewFD->setTemplateParameterListsInfo(Context,
7943 TemplateParamLists.drop_back(1));
7946 // This is a function template specialization.
7947 isFunctionTemplateSpecialization = true;
7948 // For source fidelity, store all the template param lists.
7949 if (TemplateParamLists.size() > 0)
7950 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
7952 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);".
7954 // We want to remove the "template<>", found here.
7955 SourceRange RemoveRange = TemplateParams->getSourceRange();
7957 // If we remove the template<> and the name is not a
7958 // template-id, we're actually silently creating a problem:
7959 // the friend declaration will refer to an untemplated decl,
7960 // and clearly the user wants a template specialization. So
7961 // we need to insert '<>' after the name.
7962 SourceLocation InsertLoc;
7963 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
7964 InsertLoc = D.getName().getSourceRange().getEnd();
7965 InsertLoc = getLocForEndOfToken(InsertLoc);
7968 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend)
7969 << Name << RemoveRange
7970 << FixItHint::CreateRemoval(RemoveRange)
7971 << FixItHint::CreateInsertion(InsertLoc, "<>");
7976 // All template param lists were matched against the scope specifier:
7977 // this is NOT (an explicit specialization of) a template.
7978 if (TemplateParamLists.size() > 0)
7979 // For source fidelity, store all the template param lists.
7980 NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists);
7984 NewFD->setInvalidDecl();
7985 if (FunctionTemplate)
7986 FunctionTemplate->setInvalidDecl();
7989 // C++ [dcl.fct.spec]p5:
7990 // The virtual specifier shall only be used in declarations of
7991 // nonstatic class member functions that appear within a
7992 // member-specification of a class declaration; see 10.3.
7994 if (isVirtual && !NewFD->isInvalidDecl()) {
7995 if (!isVirtualOkay) {
7996 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7997 diag::err_virtual_non_function);
7998 } else if (!CurContext->isRecord()) {
7999 // 'virtual' was specified outside of the class.
8000 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8001 diag::err_virtual_out_of_class)
8002 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
8003 } else if (NewFD->getDescribedFunctionTemplate()) {
8004 // C++ [temp.mem]p3:
8005 // A member function template shall not be virtual.
8006 Diag(D.getDeclSpec().getVirtualSpecLoc(),
8007 diag::err_virtual_member_function_template)
8008 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
8010 // Okay: Add virtual to the method.
8011 NewFD->setVirtualAsWritten(true);
8014 if (getLangOpts().CPlusPlus14 &&
8015 NewFD->getReturnType()->isUndeducedType())
8016 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual);
8019 if (getLangOpts().CPlusPlus14 &&
8020 (NewFD->isDependentContext() ||
8021 (isFriend && CurContext->isDependentContext())) &&
8022 NewFD->getReturnType()->isUndeducedType()) {
8023 // If the function template is referenced directly (for instance, as a
8024 // member of the current instantiation), pretend it has a dependent type.
8025 // This is not really justified by the standard, but is the only sane
8027 // FIXME: For a friend function, we have not marked the function as being
8028 // a friend yet, so 'isDependentContext' on the FD doesn't work.
8029 const FunctionProtoType *FPT =
8030 NewFD->getType()->castAs<FunctionProtoType>();
8032 SubstAutoType(FPT->getReturnType(), Context.DependentTy);
8033 NewFD->setType(Context.getFunctionType(Result, FPT->getParamTypes(),
8034 FPT->getExtProtoInfo()));
8037 // C++ [dcl.fct.spec]p3:
8038 // The inline specifier shall not appear on a block scope function
8040 if (isInline && !NewFD->isInvalidDecl()) {
8041 if (CurContext->isFunctionOrMethod()) {
8042 // 'inline' is not allowed on block scope function declaration.
8043 Diag(D.getDeclSpec().getInlineSpecLoc(),
8044 diag::err_inline_declaration_block_scope) << Name
8045 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
8049 // C++ [dcl.fct.spec]p6:
8050 // The explicit specifier shall be used only in the declaration of a
8051 // constructor or conversion function within its class definition;
8052 // see 12.3.1 and 12.3.2.
8053 if (isExplicit && !NewFD->isInvalidDecl()) {
8054 if (!CurContext->isRecord()) {
8055 // 'explicit' was specified outside of the class.
8056 Diag(D.getDeclSpec().getExplicitSpecLoc(),
8057 diag::err_explicit_out_of_class)
8058 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
8059 } else if (!isa<CXXConstructorDecl>(NewFD) &&
8060 !isa<CXXConversionDecl>(NewFD)) {
8061 // 'explicit' was specified on a function that wasn't a constructor
8062 // or conversion function.
8063 Diag(D.getDeclSpec().getExplicitSpecLoc(),
8064 diag::err_explicit_non_ctor_or_conv_function)
8065 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
8070 // C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors
8071 // are implicitly inline.
8072 NewFD->setImplicitlyInline();
8074 // C++11 [dcl.constexpr]p3: functions declared constexpr are required to
8075 // be either constructors or to return a literal type. Therefore,
8076 // destructors cannot be declared constexpr.
8077 if (isa<CXXDestructorDecl>(NewFD))
8078 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor);
8082 // This is a function concept.
8083 if (FunctionTemplateDecl *FTD = NewFD->getDescribedFunctionTemplate())
8086 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
8087 // applied only to the definition of a function template [...]
8088 if (!D.isFunctionDefinition()) {
8089 Diag(D.getDeclSpec().getConceptSpecLoc(),
8090 diag::err_function_concept_not_defined);
8091 NewFD->setInvalidDecl();
8094 // C++ Concepts TS [dcl.spec.concept]p1: [...] A function concept shall
8095 // have no exception-specification and is treated as if it were specified
8096 // with noexcept(true) (15.4). [...]
8097 if (const FunctionProtoType *FPT = R->getAs<FunctionProtoType>()) {
8098 if (FPT->hasExceptionSpec()) {
8100 if (D.isFunctionDeclarator())
8101 Range = D.getFunctionTypeInfo().getExceptionSpecRange();
8102 Diag(NewFD->getLocation(), diag::err_function_concept_exception_spec)
8103 << FixItHint::CreateRemoval(Range);
8104 NewFD->setInvalidDecl();
8106 Context.adjustExceptionSpec(NewFD, EST_BasicNoexcept);
8109 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
8110 // following restrictions:
8111 // - The declared return type shall have the type bool.
8112 if (!Context.hasSameType(FPT->getReturnType(), Context.BoolTy)) {
8113 Diag(D.getIdentifierLoc(), diag::err_function_concept_bool_ret);
8114 NewFD->setInvalidDecl();
8117 // C++ Concepts TS [dcl.spec.concept]p5: A function concept has the
8118 // following restrictions:
8119 // - The declaration's parameter list shall be equivalent to an empty
8121 if (FPT->getNumParams() > 0 || FPT->isVariadic())
8122 Diag(NewFD->getLocation(), diag::err_function_concept_with_params);
8125 // C++ Concepts TS [dcl.spec.concept]p2: Every concept definition is
8126 // implicity defined to be a constexpr declaration (implicitly inline)
8127 NewFD->setImplicitlyInline();
8129 // C++ Concepts TS [dcl.spec.concept]p2: A concept definition shall not
8130 // be declared with the thread_local, inline, friend, or constexpr
8131 // specifiers, [...]
8133 Diag(D.getDeclSpec().getInlineSpecLoc(),
8134 diag::err_concept_decl_invalid_specifiers)
8136 NewFD->setInvalidDecl(true);
8140 Diag(D.getDeclSpec().getFriendSpecLoc(),
8141 diag::err_concept_decl_invalid_specifiers)
8143 NewFD->setInvalidDecl(true);
8147 Diag(D.getDeclSpec().getConstexprSpecLoc(),
8148 diag::err_concept_decl_invalid_specifiers)
8150 NewFD->setInvalidDecl(true);
8153 // C++ Concepts TS [dcl.spec.concept]p1: The concept specifier shall be
8154 // applied only to the definition of a function template or variable
8155 // template, declared in namespace scope.
8156 if (isFunctionTemplateSpecialization) {
8157 Diag(D.getDeclSpec().getConceptSpecLoc(),
8158 diag::err_concept_specified_specialization) << 1;
8159 NewFD->setInvalidDecl(true);
8164 // If __module_private__ was specified, mark the function accordingly.
8165 if (D.getDeclSpec().isModulePrivateSpecified()) {
8166 if (isFunctionTemplateSpecialization) {
8167 SourceLocation ModulePrivateLoc
8168 = D.getDeclSpec().getModulePrivateSpecLoc();
8169 Diag(ModulePrivateLoc, diag::err_module_private_specialization)
8171 << FixItHint::CreateRemoval(ModulePrivateLoc);
8173 NewFD->setModulePrivate();
8174 if (FunctionTemplate)
8175 FunctionTemplate->setModulePrivate();
8180 if (FunctionTemplate) {
8181 FunctionTemplate->setObjectOfFriendDecl();
8182 FunctionTemplate->setAccess(AS_public);
8184 NewFD->setObjectOfFriendDecl();
8185 NewFD->setAccess(AS_public);
8188 // If a function is defined as defaulted or deleted, mark it as such now.
8189 // FIXME: Does this ever happen? ActOnStartOfFunctionDef forces the function
8190 // definition kind to FDK_Definition.
8191 switch (D.getFunctionDefinitionKind()) {
8192 case FDK_Declaration:
8193 case FDK_Definition:
8197 NewFD->setDefaulted();
8201 NewFD->setDeletedAsWritten();
8205 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext &&
8206 D.isFunctionDefinition()) {
8207 // C++ [class.mfct]p2:
8208 // A member function may be defined (8.4) in its class definition, in
8209 // which case it is an inline member function (7.1.2)
8210 NewFD->setImplicitlyInline();
8213 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) &&
8214 !CurContext->isRecord()) {
8215 // C++ [class.static]p1:
8216 // A data or function member of a class may be declared static
8217 // in a class definition, in which case it is a static member of
8220 // Complain about the 'static' specifier if it's on an out-of-line
8221 // member function definition.
8222 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
8223 diag::err_static_out_of_line)
8224 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
8227 // C++11 [except.spec]p15:
8228 // A deallocation function with no exception-specification is treated
8229 // as if it were specified with noexcept(true).
8230 const FunctionProtoType *FPT = R->getAs<FunctionProtoType>();
8231 if ((Name.getCXXOverloadedOperator() == OO_Delete ||
8232 Name.getCXXOverloadedOperator() == OO_Array_Delete) &&
8233 getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec())
8234 NewFD->setType(Context.getFunctionType(
8235 FPT->getReturnType(), FPT->getParamTypes(),
8236 FPT->getExtProtoInfo().withExceptionSpec(EST_BasicNoexcept)));
8239 // Filter out previous declarations that don't match the scope.
8240 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewFD),
8241 D.getCXXScopeSpec().isNotEmpty() ||
8242 isExplicitSpecialization ||
8243 isFunctionTemplateSpecialization);
8245 // Handle GNU asm-label extension (encoded as an attribute).
8246 if (Expr *E = (Expr*) D.getAsmLabel()) {
8247 // The parser guarantees this is a string.
8248 StringLiteral *SE = cast<StringLiteral>(E);
8249 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context,
8250 SE->getString(), 0));
8251 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
8252 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
8253 ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier());
8254 if (I != ExtnameUndeclaredIdentifiers.end()) {
8255 if (isDeclExternC(NewFD)) {
8256 NewFD->addAttr(I->second);
8257 ExtnameUndeclaredIdentifiers.erase(I);
8259 Diag(NewFD->getLocation(), diag::warn_redefine_extname_not_applied)
8260 << /*Variable*/0 << NewFD;
8264 // Copy the parameter declarations from the declarator D to the function
8265 // declaration NewFD, if they are available. First scavenge them into Params.
8266 SmallVector<ParmVarDecl*, 16> Params;
8268 if (D.isFunctionDeclarator(FTIIdx)) {
8269 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(FTIIdx).Fun;
8271 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs
8272 // function that takes no arguments, not a function that takes a
8273 // single void argument.
8274 // We let through "const void" here because Sema::GetTypeForDeclarator
8275 // already checks for that case.
8276 if (FTIHasNonVoidParameters(FTI) && FTI.Params[0].Param) {
8277 for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) {
8278 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
8279 assert(Param->getDeclContext() != NewFD && "Was set before ?");
8280 Param->setDeclContext(NewFD);
8281 Params.push_back(Param);
8283 if (Param->isInvalidDecl())
8284 NewFD->setInvalidDecl();
8288 if (!getLangOpts().CPlusPlus) {
8289 // In C, find all the tag declarations from the prototype and move them
8290 // into the function DeclContext. Remove them from the surrounding tag
8291 // injection context of the function, which is typically but not always
8293 DeclContext *PrototypeTagContext =
8294 getTagInjectionContext(NewFD->getLexicalDeclContext());
8295 for (NamedDecl *NonParmDecl : FTI.getDeclsInPrototype()) {
8296 auto *TD = dyn_cast<TagDecl>(NonParmDecl);
8298 // We don't want to reparent enumerators. Look at their parent enum
8301 if (auto *ECD = dyn_cast<EnumConstantDecl>(NonParmDecl))
8302 TD = cast<EnumDecl>(ECD->getDeclContext());
8306 DeclContext *TagDC = TD->getLexicalDeclContext();
8307 if (!TagDC->containsDecl(TD))
8309 TagDC->removeDecl(TD);
8310 TD->setDeclContext(NewFD);
8313 // Preserve the lexical DeclContext if it is not the surrounding tag
8314 // injection context of the FD. In this example, the semantic context of
8315 // E will be f and the lexical context will be S, while both the
8316 // semantic and lexical contexts of S will be f:
8317 // void f(struct S { enum E { a } f; } s);
8318 if (TagDC != PrototypeTagContext)
8319 TD->setLexicalDeclContext(TagDC);
8322 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) {
8323 // When we're declaring a function with a typedef, typeof, etc as in the
8324 // following example, we'll need to synthesize (unnamed)
8325 // parameters for use in the declaration.
8328 // typedef void fn(int);
8332 // Synthesize a parameter for each argument type.
8333 for (const auto &AI : FT->param_types()) {
8334 ParmVarDecl *Param =
8335 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), AI);
8336 Param->setScopeInfo(0, Params.size());
8337 Params.push_back(Param);
8340 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 &&
8341 "Should not need args for typedef of non-prototype fn");
8344 // Finally, we know we have the right number of parameters, install them.
8345 NewFD->setParams(Params);
8347 if (D.getDeclSpec().isNoreturnSpecified())
8349 ::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(),
8352 // Functions returning a variably modified type violate C99 6.7.5.2p2
8353 // because all functions have linkage.
8354 if (!NewFD->isInvalidDecl() &&
8355 NewFD->getReturnType()->isVariablyModifiedType()) {
8356 Diag(NewFD->getLocation(), diag::err_vm_func_decl);
8357 NewFD->setInvalidDecl();
8360 // Apply an implicit SectionAttr if #pragma code_seg is active.
8361 if (CodeSegStack.CurrentValue && D.isFunctionDefinition() &&
8362 !NewFD->hasAttr<SectionAttr>()) {
8364 SectionAttr::CreateImplicit(Context, SectionAttr::Declspec_allocate,
8365 CodeSegStack.CurrentValue->getString(),
8366 CodeSegStack.CurrentPragmaLocation));
8367 if (UnifySection(CodeSegStack.CurrentValue->getString(),
8368 ASTContext::PSF_Implicit | ASTContext::PSF_Execute |
8369 ASTContext::PSF_Read,
8371 NewFD->dropAttr<SectionAttr>();
8374 // Handle attributes.
8375 ProcessDeclAttributes(S, NewFD, D);
8377 if (getLangOpts().OpenCL) {
8378 // OpenCL v1.1 s6.5: Using an address space qualifier in a function return
8379 // type declaration will generate a compilation error.
8380 unsigned AddressSpace = NewFD->getReturnType().getAddressSpace();
8381 if (AddressSpace == LangAS::opencl_local ||
8382 AddressSpace == LangAS::opencl_global ||
8383 AddressSpace == LangAS::opencl_constant) {
8384 Diag(NewFD->getLocation(),
8385 diag::err_opencl_return_value_with_address_space);
8386 NewFD->setInvalidDecl();
8390 if (!getLangOpts().CPlusPlus) {
8391 // Perform semantic checking on the function declaration.
8392 bool isExplicitSpecialization=false;
8393 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8394 CheckMain(NewFD, D.getDeclSpec());
8396 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8397 CheckMSVCRTEntryPoint(NewFD);
8399 if (!NewFD->isInvalidDecl())
8400 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8401 isExplicitSpecialization));
8402 else if (!Previous.empty())
8403 // Recover gracefully from an invalid redeclaration.
8404 D.setRedeclaration(true);
8405 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8406 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8407 "previous declaration set still overloaded");
8409 // Diagnose no-prototype function declarations with calling conventions that
8410 // don't support variadic calls. Only do this in C and do it after merging
8411 // possibly prototyped redeclarations.
8412 const FunctionType *FT = NewFD->getType()->castAs<FunctionType>();
8413 if (isa<FunctionNoProtoType>(FT) && !D.isFunctionDefinition()) {
8414 CallingConv CC = FT->getExtInfo().getCC();
8415 if (!supportsVariadicCall(CC)) {
8416 // Windows system headers sometimes accidentally use stdcall without
8417 // (void) parameters, so we relax this to a warning.
8419 CC == CC_X86StdCall ? diag::warn_cconv_knr : diag::err_cconv_knr;
8420 Diag(NewFD->getLocation(), DiagID)
8421 << FunctionType::getNameForCallConv(CC);
8425 // C++11 [replacement.functions]p3:
8426 // The program's definitions shall not be specified as inline.
8428 // N.B. We diagnose declarations instead of definitions per LWG issue 2340.
8430 // Suppress the diagnostic if the function is __attribute__((used)), since
8431 // that forces an external definition to be emitted.
8432 if (D.getDeclSpec().isInlineSpecified() &&
8433 NewFD->isReplaceableGlobalAllocationFunction() &&
8434 !NewFD->hasAttr<UsedAttr>())
8435 Diag(D.getDeclSpec().getInlineSpecLoc(),
8436 diag::ext_operator_new_delete_declared_inline)
8437 << NewFD->getDeclName();
8439 // If the declarator is a template-id, translate the parser's template
8440 // argument list into our AST format.
8441 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
8442 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
8443 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
8444 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
8445 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
8446 TemplateId->NumArgs);
8447 translateTemplateArguments(TemplateArgsPtr,
8450 HasExplicitTemplateArgs = true;
8452 if (NewFD->isInvalidDecl()) {
8453 HasExplicitTemplateArgs = false;
8454 } else if (FunctionTemplate) {
8455 // Function template with explicit template arguments.
8456 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec)
8457 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc);
8459 HasExplicitTemplateArgs = false;
8461 assert((isFunctionTemplateSpecialization ||
8462 D.getDeclSpec().isFriendSpecified()) &&
8463 "should have a 'template<>' for this decl");
8464 // "friend void foo<>(int);" is an implicit specialization decl.
8465 isFunctionTemplateSpecialization = true;
8467 } else if (isFriend && isFunctionTemplateSpecialization) {
8468 // This combination is only possible in a recovery case; the user
8469 // wrote something like:
8470 // template <> friend void foo(int);
8471 // which we're recovering from as if the user had written:
8472 // friend void foo<>(int);
8473 // Go ahead and fake up a template id.
8474 HasExplicitTemplateArgs = true;
8475 TemplateArgs.setLAngleLoc(D.getIdentifierLoc());
8476 TemplateArgs.setRAngleLoc(D.getIdentifierLoc());
8479 // We do not add HD attributes to specializations here because
8480 // they may have different constexpr-ness compared to their
8481 // templates and, after maybeAddCUDAHostDeviceAttrs() is applied,
8482 // may end up with different effective targets. Instead, a
8483 // specialization inherits its target attributes from its template
8484 // in the CheckFunctionTemplateSpecialization() call below.
8485 if (getLangOpts().CUDA & !isFunctionTemplateSpecialization)
8486 maybeAddCUDAHostDeviceAttrs(NewFD, Previous);
8488 // If it's a friend (and only if it's a friend), it's possible
8489 // that either the specialized function type or the specialized
8490 // template is dependent, and therefore matching will fail. In
8491 // this case, don't check the specialization yet.
8492 bool InstantiationDependent = false;
8493 if (isFunctionTemplateSpecialization && isFriend &&
8494 (NewFD->getType()->isDependentType() || DC->isDependentContext() ||
8495 TemplateSpecializationType::anyDependentTemplateArguments(
8497 InstantiationDependent))) {
8498 assert(HasExplicitTemplateArgs &&
8499 "friend function specialization without template args");
8500 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs,
8502 NewFD->setInvalidDecl();
8503 } else if (isFunctionTemplateSpecialization) {
8504 if (CurContext->isDependentContext() && CurContext->isRecord()
8506 isDependentClassScopeExplicitSpecialization = true;
8507 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
8508 diag::ext_function_specialization_in_class :
8509 diag::err_function_specialization_in_class)
8510 << NewFD->getDeclName();
8511 } else if (CheckFunctionTemplateSpecialization(NewFD,
8512 (HasExplicitTemplateArgs ? &TemplateArgs
8515 NewFD->setInvalidDecl();
8518 // A storage-class-specifier shall not be specified in an explicit
8519 // specialization (14.7.3)
8520 FunctionTemplateSpecializationInfo *Info =
8521 NewFD->getTemplateSpecializationInfo();
8522 if (Info && SC != SC_None) {
8523 if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass())
8524 Diag(NewFD->getLocation(),
8525 diag::err_explicit_specialization_inconsistent_storage_class)
8527 << FixItHint::CreateRemoval(
8528 D.getDeclSpec().getStorageClassSpecLoc());
8531 Diag(NewFD->getLocation(),
8532 diag::ext_explicit_specialization_storage_class)
8533 << FixItHint::CreateRemoval(
8534 D.getDeclSpec().getStorageClassSpecLoc());
8536 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) {
8537 if (CheckMemberSpecialization(NewFD, Previous))
8538 NewFD->setInvalidDecl();
8541 // Perform semantic checking on the function declaration.
8542 if (!isDependentClassScopeExplicitSpecialization) {
8543 if (!NewFD->isInvalidDecl() && NewFD->isMain())
8544 CheckMain(NewFD, D.getDeclSpec());
8546 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
8547 CheckMSVCRTEntryPoint(NewFD);
8549 if (!NewFD->isInvalidDecl())
8550 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
8551 isExplicitSpecialization));
8552 else if (!Previous.empty())
8553 // Recover gracefully from an invalid redeclaration.
8554 D.setRedeclaration(true);
8557 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
8558 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
8559 "previous declaration set still overloaded");
8561 NamedDecl *PrincipalDecl = (FunctionTemplate
8562 ? cast<NamedDecl>(FunctionTemplate)
8565 if (isFriend && NewFD->getPreviousDecl()) {
8566 AccessSpecifier Access = AS_public;
8567 if (!NewFD->isInvalidDecl())
8568 Access = NewFD->getPreviousDecl()->getAccess();
8570 NewFD->setAccess(Access);
8571 if (FunctionTemplate) FunctionTemplate->setAccess(Access);
8574 if (NewFD->isOverloadedOperator() && !DC->isRecord() &&
8575 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
8576 PrincipalDecl->setNonMemberOperator();
8578 // If we have a function template, check the template parameter
8579 // list. This will check and merge default template arguments.
8580 if (FunctionTemplate) {
8581 FunctionTemplateDecl *PrevTemplate =
8582 FunctionTemplate->getPreviousDecl();
8583 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(),
8584 PrevTemplate ? PrevTemplate->getTemplateParameters()
8586 D.getDeclSpec().isFriendSpecified()
8587 ? (D.isFunctionDefinition()
8588 ? TPC_FriendFunctionTemplateDefinition
8589 : TPC_FriendFunctionTemplate)
8590 : (D.getCXXScopeSpec().isSet() &&
8591 DC && DC->isRecord() &&
8592 DC->isDependentContext())
8593 ? TPC_ClassTemplateMember
8594 : TPC_FunctionTemplate);
8597 if (NewFD->isInvalidDecl()) {
8598 // Ignore all the rest of this.
8599 } else if (!D.isRedeclaration()) {
8600 struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists,
8602 // Fake up an access specifier if it's supposed to be a class member.
8603 if (isa<CXXRecordDecl>(NewFD->getDeclContext()))
8604 NewFD->setAccess(AS_public);
8606 // Qualified decls generally require a previous declaration.
8607 if (D.getCXXScopeSpec().isSet()) {
8608 // ...with the major exception of templated-scope or
8609 // dependent-scope friend declarations.
8611 // TODO: we currently also suppress this check in dependent
8612 // contexts because (1) the parameter depth will be off when
8613 // matching friend templates and (2) we might actually be
8614 // selecting a friend based on a dependent factor. But there
8615 // are situations where these conditions don't apply and we
8616 // can actually do this check immediately.
8618 (TemplateParamLists.size() ||
8619 D.getCXXScopeSpec().getScopeRep()->isDependent() ||
8620 CurContext->isDependentContext())) {
8623 // The user tried to provide an out-of-line definition for a
8624 // function that is a member of a class or namespace, but there
8625 // was no such member function declared (C++ [class.mfct]p2,
8626 // C++ [namespace.memdef]p2). For example:
8632 // void X::f() { } // ill-formed
8634 // Complain about this problem, and attempt to suggest close
8635 // matches (e.g., those that differ only in cv-qualifiers and
8636 // whether the parameter types are references).
8638 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8639 *this, Previous, NewFD, ExtraArgs, false, nullptr)) {
8640 AddToScope = ExtraArgs.AddToScope;
8645 // Unqualified local friend declarations are required to resolve
8647 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) {
8648 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
8649 *this, Previous, NewFD, ExtraArgs, true, S)) {
8650 AddToScope = ExtraArgs.AddToScope;
8654 } else if (!D.isFunctionDefinition() &&
8655 isa<CXXMethodDecl>(NewFD) && NewFD->isOutOfLine() &&
8656 !isFriend && !isFunctionTemplateSpecialization &&
8657 !isExplicitSpecialization) {
8658 // An out-of-line member function declaration must also be a
8659 // definition (C++ [class.mfct]p2).
8660 // Note that this is not the case for explicit specializations of
8661 // function templates or member functions of class templates, per
8662 // C++ [temp.expl.spec]p2. We also allow these declarations as an
8663 // extension for compatibility with old SWIG code which likes to
8665 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration)
8666 << D.getCXXScopeSpec().getRange();
8670 ProcessPragmaWeak(S, NewFD);
8671 checkAttributesAfterMerging(*this, *NewFD);
8673 AddKnownFunctionAttributes(NewFD);
8675 if (NewFD->hasAttr<OverloadableAttr>() &&
8676 !NewFD->getType()->getAs<FunctionProtoType>()) {
8677 Diag(NewFD->getLocation(),
8678 diag::err_attribute_overloadable_no_prototype)
8681 // Turn this into a variadic function with no parameters.
8682 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>();
8683 FunctionProtoType::ExtProtoInfo EPI(
8684 Context.getDefaultCallingConvention(true, false));
8685 EPI.Variadic = true;
8686 EPI.ExtInfo = FT->getExtInfo();
8688 QualType R = Context.getFunctionType(FT->getReturnType(), None, EPI);
8692 // If there's a #pragma GCC visibility in scope, and this isn't a class
8693 // member, set the visibility of this function.
8694 if (!DC->isRecord() && NewFD->isExternallyVisible())
8695 AddPushedVisibilityAttribute(NewFD);
8697 // If there's a #pragma clang arc_cf_code_audited in scope, consider
8698 // marking the function.
8699 AddCFAuditedAttribute(NewFD);
8701 // If this is a function definition, check if we have to apply optnone due to
8703 if(D.isFunctionDefinition())
8704 AddRangeBasedOptnone(NewFD);
8706 // If this is the first declaration of an extern C variable, update
8707 // the map of such variables.
8708 if (NewFD->isFirstDecl() && !NewFD->isInvalidDecl() &&
8709 isIncompleteDeclExternC(*this, NewFD))
8710 RegisterLocallyScopedExternCDecl(NewFD, S);
8712 // Set this FunctionDecl's range up to the right paren.
8713 NewFD->setRangeEnd(D.getSourceRange().getEnd());
8715 if (D.isRedeclaration() && !Previous.empty()) {
8716 checkDLLAttributeRedeclaration(
8717 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewFD,
8718 isExplicitSpecialization || isFunctionTemplateSpecialization,
8719 D.isFunctionDefinition());
8722 if (getLangOpts().CUDA) {
8723 IdentifierInfo *II = NewFD->getIdentifier();
8724 if (II && II->isStr("cudaConfigureCall") && !NewFD->isInvalidDecl() &&
8725 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
8726 if (!R->getAs<FunctionType>()->getReturnType()->isScalarType())
8727 Diag(NewFD->getLocation(), diag::err_config_scalar_return);
8729 Context.setcudaConfigureCallDecl(NewFD);
8732 // Variadic functions, other than a *declaration* of printf, are not allowed
8733 // in device-side CUDA code, unless someone passed
8734 // -fcuda-allow-variadic-functions.
8735 if (!getLangOpts().CUDAAllowVariadicFunctions && NewFD->isVariadic() &&
8736 (NewFD->hasAttr<CUDADeviceAttr>() ||
8737 NewFD->hasAttr<CUDAGlobalAttr>()) &&
8738 !(II && II->isStr("printf") && NewFD->isExternC() &&
8739 !D.isFunctionDefinition())) {
8740 Diag(NewFD->getLocation(), diag::err_variadic_device_fn);
8744 if (getLangOpts().CPlusPlus) {
8745 if (FunctionTemplate) {
8746 if (NewFD->isInvalidDecl())
8747 FunctionTemplate->setInvalidDecl();
8748 return FunctionTemplate;
8752 if (NewFD->hasAttr<OpenCLKernelAttr>()) {
8753 // OpenCL v1.2 s6.8 static is invalid for kernel functions.
8754 if ((getLangOpts().OpenCLVersion >= 120)
8755 && (SC == SC_Static)) {
8756 Diag(D.getIdentifierLoc(), diag::err_static_kernel);
8760 // OpenCL v1.2, s6.9 -- Kernels can only have return type void.
8761 if (!NewFD->getReturnType()->isVoidType()) {
8762 SourceRange RTRange = NewFD->getReturnTypeSourceRange();
8763 Diag(D.getIdentifierLoc(), diag::err_expected_kernel_void_return_type)
8764 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "void")
8769 llvm::SmallPtrSet<const Type *, 16> ValidTypes;
8770 for (auto Param : NewFD->parameters())
8771 checkIsValidOpenCLKernelParameter(*this, D, Param, ValidTypes);
8773 for (const ParmVarDecl *Param : NewFD->parameters()) {
8774 QualType PT = Param->getType();
8776 // OpenCL 2.0 pipe restrictions forbids pipe packet types to be non-value
8778 if (getLangOpts().OpenCLVersion >= 200) {
8779 if(const PipeType *PipeTy = PT->getAs<PipeType>()) {
8780 QualType ElemTy = PipeTy->getElementType();
8781 if (ElemTy->isReferenceType() || ElemTy->isPointerType()) {
8782 Diag(Param->getTypeSpecStartLoc(), diag::err_reference_pipe_type );
8789 MarkUnusedFileScopedDecl(NewFD);
8791 // Here we have an function template explicit specialization at class scope.
8792 // The actually specialization will be postponed to template instatiation
8793 // time via the ClassScopeFunctionSpecializationDecl node.
8794 if (isDependentClassScopeExplicitSpecialization) {
8795 ClassScopeFunctionSpecializationDecl *NewSpec =
8796 ClassScopeFunctionSpecializationDecl::Create(
8797 Context, CurContext, SourceLocation(),
8798 cast<CXXMethodDecl>(NewFD),
8799 HasExplicitTemplateArgs, TemplateArgs);
8800 CurContext->addDecl(NewSpec);
8807 /// \brief Checks if the new declaration declared in dependent context must be
8808 /// put in the same redeclaration chain as the specified declaration.
8810 /// \param D Declaration that is checked.
8811 /// \param PrevDecl Previous declaration found with proper lookup method for the
8812 /// same declaration name.
8813 /// \returns True if D must be added to the redeclaration chain which PrevDecl
8816 bool Sema::shouldLinkDependentDeclWithPrevious(Decl *D, Decl *PrevDecl) {
8817 // Any declarations should be put into redeclaration chains except for
8818 // friend declaration in a dependent context that names a function in
8821 // This allows to compile code like:
8824 // template<typename T> class C1 { friend void func() { } };
8825 // template<typename T> class C2 { friend void func() { } };
8827 // This code snippet is a valid code unless both templates are instantiated.
8828 return !(D->getLexicalDeclContext()->isDependentContext() &&
8829 D->getDeclContext()->isFileContext() &&
8830 D->getFriendObjectKind() != Decl::FOK_None);
8833 /// \brief Perform semantic checking of a new function declaration.
8835 /// Performs semantic analysis of the new function declaration
8836 /// NewFD. This routine performs all semantic checking that does not
8837 /// require the actual declarator involved in the declaration, and is
8838 /// used both for the declaration of functions as they are parsed
8839 /// (called via ActOnDeclarator) and for the declaration of functions
8840 /// that have been instantiated via C++ template instantiation (called
8841 /// via InstantiateDecl).
8843 /// \param IsExplicitSpecialization whether this new function declaration is
8844 /// an explicit specialization of the previous declaration.
8846 /// This sets NewFD->isInvalidDecl() to true if there was an error.
8848 /// \returns true if the function declaration is a redeclaration.
8849 bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
8850 LookupResult &Previous,
8851 bool IsExplicitSpecialization) {
8852 assert(!NewFD->getReturnType()->isVariablyModifiedType() &&
8853 "Variably modified return types are not handled here");
8855 // Determine whether the type of this function should be merged with
8856 // a previous visible declaration. This never happens for functions in C++,
8857 // and always happens in C if the previous declaration was visible.
8858 bool MergeTypeWithPrevious = !getLangOpts().CPlusPlus &&
8859 !Previous.isShadowed();
8861 bool Redeclaration = false;
8862 NamedDecl *OldDecl = nullptr;
8864 // Merge or overload the declaration with an existing declaration of
8865 // the same name, if appropriate.
8866 if (!Previous.empty()) {
8867 // Determine whether NewFD is an overload of PrevDecl or
8868 // a declaration that requires merging. If it's an overload,
8869 // there's no more work to do here; we'll just add the new
8870 // function to the scope.
8871 if (!AllowOverloadingOfFunction(Previous, Context)) {
8872 NamedDecl *Candidate = Previous.getRepresentativeDecl();
8873 if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) {
8874 Redeclaration = true;
8875 OldDecl = Candidate;
8878 switch (CheckOverload(S, NewFD, Previous, OldDecl,
8879 /*NewIsUsingDecl*/ false)) {
8881 Redeclaration = true;
8884 case Ovl_NonFunction:
8885 Redeclaration = true;
8889 Redeclaration = false;
8893 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
8894 // If a function name is overloadable in C, then every function
8895 // with that name must be marked "overloadable".
8896 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
8897 << Redeclaration << NewFD;
8898 NamedDecl *OverloadedDecl = nullptr;
8900 OverloadedDecl = OldDecl;
8901 else if (!Previous.empty())
8902 OverloadedDecl = Previous.getRepresentativeDecl();
8904 Diag(OverloadedDecl->getLocation(),
8905 diag::note_attribute_overloadable_prev_overload);
8906 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
8911 // Check for a previous extern "C" declaration with this name.
8912 if (!Redeclaration &&
8913 checkForConflictWithNonVisibleExternC(*this, NewFD, Previous)) {
8914 if (!Previous.empty()) {
8915 // This is an extern "C" declaration with the same name as a previous
8916 // declaration, and thus redeclares that entity...
8917 Redeclaration = true;
8918 OldDecl = Previous.getFoundDecl();
8919 MergeTypeWithPrevious = false;
8921 // ... except in the presence of __attribute__((overloadable)).
8922 if (OldDecl->hasAttr<OverloadableAttr>()) {
8923 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
8924 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
8925 << Redeclaration << NewFD;
8926 Diag(Previous.getFoundDecl()->getLocation(),
8927 diag::note_attribute_overloadable_prev_overload);
8928 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
8930 if (IsOverload(NewFD, cast<FunctionDecl>(OldDecl), false)) {
8931 Redeclaration = false;
8938 // C++11 [dcl.constexpr]p8:
8939 // A constexpr specifier for a non-static member function that is not
8940 // a constructor declares that member function to be const.
8942 // This needs to be delayed until we know whether this is an out-of-line
8943 // definition of a static member function.
8945 // This rule is not present in C++1y, so we produce a backwards
8946 // compatibility warning whenever it happens in C++11.
8947 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
8948 if (!getLangOpts().CPlusPlus14 && MD && MD->isConstexpr() &&
8949 !MD->isStatic() && !isa<CXXConstructorDecl>(MD) &&
8950 (MD->getTypeQualifiers() & Qualifiers::Const) == 0) {
8951 CXXMethodDecl *OldMD = nullptr;
8953 OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl->getAsFunction());
8954 if (!OldMD || !OldMD->isStatic()) {
8955 const FunctionProtoType *FPT =
8956 MD->getType()->castAs<FunctionProtoType>();
8957 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
8958 EPI.TypeQuals |= Qualifiers::Const;
8959 MD->setType(Context.getFunctionType(FPT->getReturnType(),
8960 FPT->getParamTypes(), EPI));
8962 // Warn that we did this, if we're not performing template instantiation.
8963 // In that case, we'll have warned already when the template was defined.
8964 if (ActiveTemplateInstantiations.empty()) {
8965 SourceLocation AddConstLoc;
8966 if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
8967 .IgnoreParens().getAs<FunctionTypeLoc>())
8968 AddConstLoc = getLocForEndOfToken(FTL.getRParenLoc());
8970 Diag(MD->getLocation(), diag::warn_cxx14_compat_constexpr_not_const)
8971 << FixItHint::CreateInsertion(AddConstLoc, " const");
8976 if (Redeclaration) {
8977 // NewFD and OldDecl represent declarations that need to be
8979 if (MergeFunctionDecl(NewFD, OldDecl, S, MergeTypeWithPrevious)) {
8980 NewFD->setInvalidDecl();
8981 return Redeclaration;
8985 Previous.addDecl(OldDecl);
8987 if (FunctionTemplateDecl *OldTemplateDecl
8988 = dyn_cast<FunctionTemplateDecl>(OldDecl)) {
8989 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl());
8990 FunctionTemplateDecl *NewTemplateDecl
8991 = NewFD->getDescribedFunctionTemplate();
8992 assert(NewTemplateDecl && "Template/non-template mismatch");
8993 if (CXXMethodDecl *Method
8994 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) {
8995 Method->setAccess(OldTemplateDecl->getAccess());
8996 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess());
8999 // If this is an explicit specialization of a member that is a function
9000 // template, mark it as a member specialization.
9001 if (IsExplicitSpecialization &&
9002 NewTemplateDecl->getInstantiatedFromMemberTemplate()) {
9003 NewTemplateDecl->setMemberSpecialization();
9004 assert(OldTemplateDecl->isMemberSpecialization());
9005 // Explicit specializations of a member template do not inherit deleted
9006 // status from the parent member template that they are specializing.
9007 if (OldTemplateDecl->getTemplatedDecl()->isDeleted()) {
9008 FunctionDecl *const OldTemplatedDecl =
9009 OldTemplateDecl->getTemplatedDecl();
9010 assert(OldTemplatedDecl->getCanonicalDecl() == OldTemplatedDecl);
9011 OldTemplatedDecl->setDeletedAsWritten(false);
9016 if (shouldLinkDependentDeclWithPrevious(NewFD, OldDecl)) {
9017 // This needs to happen first so that 'inline' propagates.
9018 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl));
9019 if (isa<CXXMethodDecl>(NewFD))
9020 NewFD->setAccess(OldDecl->getAccess());
9025 // Semantic checking for this function declaration (in isolation).
9027 if (getLangOpts().CPlusPlus) {
9028 // C++-specific checks.
9029 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) {
9030 CheckConstructor(Constructor);
9031 } else if (CXXDestructorDecl *Destructor =
9032 dyn_cast<CXXDestructorDecl>(NewFD)) {
9033 CXXRecordDecl *Record = Destructor->getParent();
9034 QualType ClassType = Context.getTypeDeclType(Record);
9036 // FIXME: Shouldn't we be able to perform this check even when the class
9037 // type is dependent? Both gcc and edg can handle that.
9038 if (!ClassType->isDependentType()) {
9039 DeclarationName Name
9040 = Context.DeclarationNames.getCXXDestructorName(
9041 Context.getCanonicalType(ClassType));
9042 if (NewFD->getDeclName() != Name) {
9043 Diag(NewFD->getLocation(), diag::err_destructor_name);
9044 NewFD->setInvalidDecl();
9045 return Redeclaration;
9048 } else if (CXXConversionDecl *Conversion
9049 = dyn_cast<CXXConversionDecl>(NewFD)) {
9050 ActOnConversionDeclarator(Conversion);
9053 // Find any virtual functions that this function overrides.
9054 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) {
9055 if (!Method->isFunctionTemplateSpecialization() &&
9056 !Method->getDescribedFunctionTemplate() &&
9057 Method->isCanonicalDecl()) {
9058 if (AddOverriddenMethods(Method->getParent(), Method)) {
9059 // If the function was marked as "static", we have a problem.
9060 if (NewFD->getStorageClass() == SC_Static) {
9061 ReportOverrides(*this, diag::err_static_overrides_virtual, Method);
9066 if (Method->isStatic())
9067 checkThisInStaticMemberFunctionType(Method);
9070 // Extra checking for C++ overloaded operators (C++ [over.oper]).
9071 if (NewFD->isOverloadedOperator() &&
9072 CheckOverloadedOperatorDeclaration(NewFD)) {
9073 NewFD->setInvalidDecl();
9074 return Redeclaration;
9077 // Extra checking for C++0x literal operators (C++0x [over.literal]).
9078 if (NewFD->getLiteralIdentifier() &&
9079 CheckLiteralOperatorDeclaration(NewFD)) {
9080 NewFD->setInvalidDecl();
9081 return Redeclaration;
9084 // In C++, check default arguments now that we have merged decls. Unless
9085 // the lexical context is the class, because in this case this is done
9086 // during delayed parsing anyway.
9087 if (!CurContext->isRecord())
9088 CheckCXXDefaultArguments(NewFD);
9090 // If this function declares a builtin function, check the type of this
9091 // declaration against the expected type for the builtin.
9092 if (unsigned BuiltinID = NewFD->getBuiltinID()) {
9093 ASTContext::GetBuiltinTypeError Error;
9094 LookupPredefedObjCSuperType(*this, S, NewFD->getIdentifier());
9095 QualType T = Context.GetBuiltinType(BuiltinID, Error);
9096 // If the type of the builtin differs only in its exception
9097 // specification, that's OK.
9098 // FIXME: If the types do differ in this way, it would be better to
9099 // retain the 'noexcept' form of the type.
9101 !Context.hasSameFunctionTypeIgnoringExceptionSpec(T,
9103 // The type of this function differs from the type of the builtin,
9104 // so forget about the builtin entirely.
9105 Context.BuiltinInfo.forgetBuiltin(BuiltinID, Context.Idents);
9108 // If this function is declared as being extern "C", then check to see if
9109 // the function returns a UDT (class, struct, or union type) that is not C
9110 // compatible, and if it does, warn the user.
9111 // But, issue any diagnostic on the first declaration only.
9112 if (Previous.empty() && NewFD->isExternC()) {
9113 QualType R = NewFD->getReturnType();
9114 if (R->isIncompleteType() && !R->isVoidType())
9115 Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete)
9117 else if (!R.isPODType(Context) && !R->isVoidType() &&
9118 !R->isObjCObjectPointerType())
9119 Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R;
9122 // C++1z [dcl.fct]p6:
9123 // [...] whether the function has a non-throwing exception-specification
9124 // [is] part of the function type
9126 // This results in an ABI break between C++14 and C++17 for functions whose
9127 // declared type includes an exception-specification in a parameter or
9128 // return type. (Exception specifications on the function itself are OK in
9129 // most cases, and exception specifications are not permitted in most other
9130 // contexts where they could make it into a mangling.)
9131 if (!getLangOpts().CPlusPlus1z && !NewFD->getPrimaryTemplate()) {
9132 auto HasNoexcept = [&](QualType T) -> bool {
9133 // Strip off declarator chunks that could be between us and a function
9134 // type. We don't need to look far, exception specifications are very
9135 // restricted prior to C++17.
9136 if (auto *RT = T->getAs<ReferenceType>())
9137 T = RT->getPointeeType();
9138 else if (T->isAnyPointerType())
9139 T = T->getPointeeType();
9140 else if (auto *MPT = T->getAs<MemberPointerType>())
9141 T = MPT->getPointeeType();
9142 if (auto *FPT = T->getAs<FunctionProtoType>())
9143 if (FPT->isNothrow(Context))
9148 auto *FPT = NewFD->getType()->castAs<FunctionProtoType>();
9149 bool AnyNoexcept = HasNoexcept(FPT->getReturnType());
9150 for (QualType T : FPT->param_types())
9151 AnyNoexcept |= HasNoexcept(T);
9153 Diag(NewFD->getLocation(),
9154 diag::warn_cxx1z_compat_exception_spec_in_signature)
9158 if (!Redeclaration && LangOpts.CUDA)
9159 checkCUDATargetOverload(NewFD, Previous);
9161 return Redeclaration;
9164 void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) {
9165 // C++11 [basic.start.main]p3:
9166 // A program that [...] declares main to be inline, static or
9167 // constexpr is ill-formed.
9168 // C11 6.7.4p4: In a hosted environment, no function specifier(s) shall
9169 // appear in a declaration of main.
9170 // static main is not an error under C99, but we should warn about it.
9171 // We accept _Noreturn main as an extension.
9172 if (FD->getStorageClass() == SC_Static)
9173 Diag(DS.getStorageClassSpecLoc(), getLangOpts().CPlusPlus
9174 ? diag::err_static_main : diag::warn_static_main)
9175 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
9176 if (FD->isInlineSpecified())
9177 Diag(DS.getInlineSpecLoc(), diag::err_inline_main)
9178 << FixItHint::CreateRemoval(DS.getInlineSpecLoc());
9179 if (DS.isNoreturnSpecified()) {
9180 SourceLocation NoreturnLoc = DS.getNoreturnSpecLoc();
9181 SourceRange NoreturnRange(NoreturnLoc, getLocForEndOfToken(NoreturnLoc));
9182 Diag(NoreturnLoc, diag::ext_noreturn_main);
9183 Diag(NoreturnLoc, diag::note_main_remove_noreturn)
9184 << FixItHint::CreateRemoval(NoreturnRange);
9186 if (FD->isConstexpr()) {
9187 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_main)
9188 << FixItHint::CreateRemoval(DS.getConstexprSpecLoc());
9189 FD->setConstexpr(false);
9192 if (getLangOpts().OpenCL) {
9193 Diag(FD->getLocation(), diag::err_opencl_no_main)
9194 << FD->hasAttr<OpenCLKernelAttr>();
9195 FD->setInvalidDecl();
9199 QualType T = FD->getType();
9200 assert(T->isFunctionType() && "function decl is not of function type");
9201 const FunctionType* FT = T->castAs<FunctionType>();
9203 if (getLangOpts().GNUMode && !getLangOpts().CPlusPlus) {
9204 // In C with GNU extensions we allow main() to have non-integer return
9205 // type, but we should warn about the extension, and we disable the
9206 // implicit-return-zero rule.
9208 // GCC in C mode accepts qualified 'int'.
9209 if (Context.hasSameUnqualifiedType(FT->getReturnType(), Context.IntTy))
9210 FD->setHasImplicitReturnZero(true);
9212 Diag(FD->getTypeSpecStartLoc(), diag::ext_main_returns_nonint);
9213 SourceRange RTRange = FD->getReturnTypeSourceRange();
9214 if (RTRange.isValid())
9215 Diag(RTRange.getBegin(), diag::note_main_change_return_type)
9216 << FixItHint::CreateReplacement(RTRange, "int");
9219 // In C and C++, main magically returns 0 if you fall off the end;
9220 // set the flag which tells us that.
9221 // This is C++ [basic.start.main]p5 and C99 5.1.2.2.3.
9223 // All the standards say that main() should return 'int'.
9224 if (Context.hasSameType(FT->getReturnType(), Context.IntTy))
9225 FD->setHasImplicitReturnZero(true);
9227 // Otherwise, this is just a flat-out error.
9228 SourceRange RTRange = FD->getReturnTypeSourceRange();
9229 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint)
9230 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "int")
9232 FD->setInvalidDecl(true);
9236 // Treat protoless main() as nullary.
9237 if (isa<FunctionNoProtoType>(FT)) return;
9239 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT);
9240 unsigned nparams = FTP->getNumParams();
9241 assert(FD->getNumParams() == nparams);
9243 bool HasExtraParameters = (nparams > 3);
9245 if (FTP->isVariadic()) {
9246 Diag(FD->getLocation(), diag::ext_variadic_main);
9247 // FIXME: if we had information about the location of the ellipsis, we
9248 // could add a FixIt hint to remove it as a parameter.
9251 // Darwin passes an undocumented fourth argument of type char**. If
9252 // other platforms start sprouting these, the logic below will start
9254 if (nparams == 4 && Context.getTargetInfo().getTriple().isOSDarwin())
9255 HasExtraParameters = false;
9257 if (HasExtraParameters) {
9258 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams;
9259 FD->setInvalidDecl(true);
9263 // FIXME: a lot of the following diagnostics would be improved
9264 // if we had some location information about types.
9267 Context.getPointerType(Context.getPointerType(Context.CharTy));
9268 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP };
9270 for (unsigned i = 0; i < nparams; ++i) {
9271 QualType AT = FTP->getParamType(i);
9273 bool mismatch = true;
9275 if (Context.hasSameUnqualifiedType(AT, Expected[i]))
9277 else if (Expected[i] == CharPP) {
9278 // As an extension, the following forms are okay:
9280 // char const * const *
9283 QualifierCollector qs;
9284 const PointerType* PT;
9285 if ((PT = qs.strip(AT)->getAs<PointerType>()) &&
9286 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) &&
9287 Context.hasSameType(QualType(qs.strip(PT->getPointeeType()), 0),
9290 mismatch = !qs.empty();
9295 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i];
9296 // TODO: suggest replacing given type with expected type
9297 FD->setInvalidDecl(true);
9301 if (nparams == 1 && !FD->isInvalidDecl()) {
9302 Diag(FD->getLocation(), diag::warn_main_one_arg);
9305 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
9306 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
9307 FD->setInvalidDecl();
9311 void Sema::CheckMSVCRTEntryPoint(FunctionDecl *FD) {
9312 QualType T = FD->getType();
9313 assert(T->isFunctionType() && "function decl is not of function type");
9314 const FunctionType *FT = T->castAs<FunctionType>();
9316 // Set an implicit return of 'zero' if the function can return some integral,
9317 // enumeration, pointer or nullptr type.
9318 if (FT->getReturnType()->isIntegralOrEnumerationType() ||
9319 FT->getReturnType()->isAnyPointerType() ||
9320 FT->getReturnType()->isNullPtrType())
9321 // DllMain is exempt because a return value of zero means it failed.
9322 if (FD->getName() != "DllMain")
9323 FD->setHasImplicitReturnZero(true);
9325 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
9326 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
9327 FD->setInvalidDecl();
9331 bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
9332 // FIXME: Need strict checking. In C89, we need to check for
9333 // any assignment, increment, decrement, function-calls, or
9334 // commas outside of a sizeof. In C99, it's the same list,
9335 // except that the aforementioned are allowed in unevaluated
9336 // expressions. Everything else falls under the
9337 // "may accept other forms of constant expressions" exception.
9338 // (We never end up here for C++, so the constant expression
9339 // rules there don't matter.)
9340 const Expr *Culprit;
9341 if (Init->isConstantInitializer(Context, false, &Culprit))
9343 Diag(Culprit->getExprLoc(), diag::err_init_element_not_constant)
9344 << Culprit->getSourceRange();
9349 // Visits an initialization expression to see if OrigDecl is evaluated in
9350 // its own initialization and throws a warning if it does.
9351 class SelfReferenceChecker
9352 : public EvaluatedExprVisitor<SelfReferenceChecker> {
9357 bool isReferenceType;
9360 llvm::SmallVector<unsigned, 4> InitFieldIndex;
9363 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited;
9365 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context),
9366 S(S), OrigDecl(OrigDecl) {
9368 isRecordType = false;
9369 isReferenceType = false;
9371 if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) {
9372 isPODType = VD->getType().isPODType(S.Context);
9373 isRecordType = VD->getType()->isRecordType();
9374 isReferenceType = VD->getType()->isReferenceType();
9378 // For most expressions, just call the visitor. For initializer lists,
9379 // track the index of the field being initialized since fields are
9380 // initialized in order allowing use of previously initialized fields.
9381 void CheckExpr(Expr *E) {
9382 InitListExpr *InitList = dyn_cast<InitListExpr>(E);
9388 // Track and increment the index here.
9390 InitFieldIndex.push_back(0);
9391 for (auto Child : InitList->children()) {
9392 CheckExpr(cast<Expr>(Child));
9393 ++InitFieldIndex.back();
9395 InitFieldIndex.pop_back();
9398 // Returns true if MemberExpr is checked and no futher checking is needed.
9399 // Returns false if additional checking is required.
9400 bool CheckInitListMemberExpr(MemberExpr *E, bool CheckReference) {
9401 llvm::SmallVector<FieldDecl*, 4> Fields;
9403 bool ReferenceField = false;
9405 // Get the field memebers used.
9406 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9407 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
9410 Fields.push_back(FD);
9411 if (FD->getType()->isReferenceType())
9412 ReferenceField = true;
9413 Base = ME->getBase()->IgnoreParenImpCasts();
9416 // Keep checking only if the base Decl is the same.
9417 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base);
9418 if (!DRE || DRE->getDecl() != OrigDecl)
9421 // A reference field can be bound to an unininitialized field.
9422 if (CheckReference && !ReferenceField)
9425 // Convert FieldDecls to their index number.
9426 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
9427 for (const FieldDecl *I : llvm::reverse(Fields))
9428 UsedFieldIndex.push_back(I->getFieldIndex());
9430 // See if a warning is needed by checking the first difference in index
9431 // numbers. If field being used has index less than the field being
9432 // initialized, then the use is safe.
9433 for (auto UsedIter = UsedFieldIndex.begin(),
9434 UsedEnd = UsedFieldIndex.end(),
9435 OrigIter = InitFieldIndex.begin(),
9436 OrigEnd = InitFieldIndex.end();
9437 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
9438 if (*UsedIter < *OrigIter)
9440 if (*UsedIter > *OrigIter)
9444 // TODO: Add a different warning which will print the field names.
9445 HandleDeclRefExpr(DRE);
9449 // For most expressions, the cast is directly above the DeclRefExpr.
9450 // For conditional operators, the cast can be outside the conditional
9451 // operator if both expressions are DeclRefExpr's.
9452 void HandleValue(Expr *E) {
9453 E = E->IgnoreParens();
9454 if (DeclRefExpr* DRE = dyn_cast<DeclRefExpr>(E)) {
9455 HandleDeclRefExpr(DRE);
9459 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
9460 Visit(CO->getCond());
9461 HandleValue(CO->getTrueExpr());
9462 HandleValue(CO->getFalseExpr());
9466 if (BinaryConditionalOperator *BCO =
9467 dyn_cast<BinaryConditionalOperator>(E)) {
9468 Visit(BCO->getCond());
9469 HandleValue(BCO->getFalseExpr());
9473 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
9474 HandleValue(OVE->getSourceExpr());
9478 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
9479 if (BO->getOpcode() == BO_Comma) {
9480 Visit(BO->getLHS());
9481 HandleValue(BO->getRHS());
9486 if (isa<MemberExpr>(E)) {
9488 if (CheckInitListMemberExpr(cast<MemberExpr>(E),
9489 false /*CheckReference*/))
9493 Expr *Base = E->IgnoreParenImpCasts();
9494 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9495 // Check for static member variables and don't warn on them.
9496 if (!isa<FieldDecl>(ME->getMemberDecl()))
9498 Base = ME->getBase()->IgnoreParenImpCasts();
9500 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base))
9501 HandleDeclRefExpr(DRE);
9508 // Reference types not handled in HandleValue are handled here since all
9509 // uses of references are bad, not just r-value uses.
9510 void VisitDeclRefExpr(DeclRefExpr *E) {
9511 if (isReferenceType)
9512 HandleDeclRefExpr(E);
9515 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
9516 if (E->getCastKind() == CK_LValueToRValue) {
9517 HandleValue(E->getSubExpr());
9521 Inherited::VisitImplicitCastExpr(E);
9524 void VisitMemberExpr(MemberExpr *E) {
9526 if (CheckInitListMemberExpr(E, true /*CheckReference*/))
9530 // Don't warn on arrays since they can be treated as pointers.
9531 if (E->getType()->canDecayToPointerType()) return;
9533 // Warn when a non-static method call is followed by non-static member
9534 // field accesses, which is followed by a DeclRefExpr.
9535 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl());
9536 bool Warn = (MD && !MD->isStatic());
9537 Expr *Base = E->getBase()->IgnoreParenImpCasts();
9538 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
9539 if (!isa<FieldDecl>(ME->getMemberDecl()))
9541 Base = ME->getBase()->IgnoreParenImpCasts();
9544 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
9546 HandleDeclRefExpr(DRE);
9550 // The base of a MemberExpr is not a MemberExpr or a DeclRefExpr.
9551 // Visit that expression.
9555 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
9556 Expr *Callee = E->getCallee();
9558 if (isa<UnresolvedLookupExpr>(Callee))
9559 return Inherited::VisitCXXOperatorCallExpr(E);
9562 for (auto Arg: E->arguments())
9563 HandleValue(Arg->IgnoreParenImpCasts());
9566 void VisitUnaryOperator(UnaryOperator *E) {
9567 // For POD record types, addresses of its own members are well-defined.
9568 if (E->getOpcode() == UO_AddrOf && isRecordType &&
9569 isa<MemberExpr>(E->getSubExpr()->IgnoreParens())) {
9571 HandleValue(E->getSubExpr());
9575 if (E->isIncrementDecrementOp()) {
9576 HandleValue(E->getSubExpr());
9580 Inherited::VisitUnaryOperator(E);
9583 void VisitObjCMessageExpr(ObjCMessageExpr *E) {}
9585 void VisitCXXConstructExpr(CXXConstructExpr *E) {
9586 if (E->getConstructor()->isCopyConstructor()) {
9587 Expr *ArgExpr = E->getArg(0);
9588 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
9589 if (ILE->getNumInits() == 1)
9590 ArgExpr = ILE->getInit(0);
9591 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
9592 if (ICE->getCastKind() == CK_NoOp)
9593 ArgExpr = ICE->getSubExpr();
9594 HandleValue(ArgExpr);
9597 Inherited::VisitCXXConstructExpr(E);
9600 void VisitCallExpr(CallExpr *E) {
9601 // Treat std::move as a use.
9602 if (E->getNumArgs() == 1) {
9603 if (FunctionDecl *FD = E->getDirectCallee()) {
9604 if (FD->isInStdNamespace() && FD->getIdentifier() &&
9605 FD->getIdentifier()->isStr("move")) {
9606 HandleValue(E->getArg(0));
9612 Inherited::VisitCallExpr(E);
9615 void VisitBinaryOperator(BinaryOperator *E) {
9616 if (E->isCompoundAssignmentOp()) {
9617 HandleValue(E->getLHS());
9622 Inherited::VisitBinaryOperator(E);
9625 // A custom visitor for BinaryConditionalOperator is needed because the
9626 // regular visitor would check the condition and true expression separately
9627 // but both point to the same place giving duplicate diagnostics.
9628 void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
9629 Visit(E->getCond());
9630 Visit(E->getFalseExpr());
9633 void HandleDeclRefExpr(DeclRefExpr *DRE) {
9634 Decl* ReferenceDecl = DRE->getDecl();
9635 if (OrigDecl != ReferenceDecl) return;
9637 if (isReferenceType) {
9638 diag = diag::warn_uninit_self_reference_in_reference_init;
9639 } else if (cast<VarDecl>(OrigDecl)->isStaticLocal()) {
9640 diag = diag::warn_static_self_reference_in_init;
9641 } else if (isa<TranslationUnitDecl>(OrigDecl->getDeclContext()) ||
9642 isa<NamespaceDecl>(OrigDecl->getDeclContext()) ||
9643 DRE->getDecl()->getType()->isRecordType()) {
9644 diag = diag::warn_uninit_self_reference_in_init;
9646 // Local variables will be handled by the CFG analysis.
9650 S.DiagRuntimeBehavior(DRE->getLocStart(), DRE,
9652 << DRE->getNameInfo().getName()
9653 << OrigDecl->getLocation()
9654 << DRE->getSourceRange());
9658 /// CheckSelfReference - Warns if OrigDecl is used in expression E.
9659 static void CheckSelfReference(Sema &S, Decl* OrigDecl, Expr *E,
9661 // Parameters arguments are occassionially constructed with itself,
9662 // for instance, in recursive functions. Skip them.
9663 if (isa<ParmVarDecl>(OrigDecl))
9666 E = E->IgnoreParens();
9668 // Skip checking T a = a where T is not a record or reference type.
9669 // Doing so is a way to silence uninitialized warnings.
9670 if (!DirectInit && !cast<VarDecl>(OrigDecl)->getType()->isRecordType())
9671 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
9672 if (ICE->getCastKind() == CK_LValueToRValue)
9673 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()))
9674 if (DRE->getDecl() == OrigDecl)
9677 SelfReferenceChecker(S, OrigDecl).CheckExpr(E);
9679 } // end anonymous namespace
9682 // Simple wrapper to add the name of a variable or (if no variable is
9683 // available) a DeclarationName into a diagnostic.
9684 struct VarDeclOrName {
9686 DeclarationName Name;
9688 friend const Sema::SemaDiagnosticBuilder &
9689 operator<<(const Sema::SemaDiagnosticBuilder &Diag, VarDeclOrName VN) {
9690 return VN.VDecl ? Diag << VN.VDecl : Diag << VN.Name;
9693 } // end anonymous namespace
9695 QualType Sema::deduceVarTypeFromInitializer(VarDecl *VDecl,
9696 DeclarationName Name, QualType Type,
9697 TypeSourceInfo *TSI,
9698 SourceRange Range, bool DirectInit,
9700 bool IsInitCapture = !VDecl;
9701 assert((!VDecl || !VDecl->isInitCapture()) &&
9702 "init captures are expected to be deduced prior to initialization");
9704 VarDeclOrName VN{VDecl, Name};
9706 ArrayRef<Expr *> DeduceInits = Init;
9708 if (auto *PL = dyn_cast<ParenListExpr>(Init))
9709 DeduceInits = PL->exprs();
9710 else if (auto *IL = dyn_cast<InitListExpr>(Init))
9711 DeduceInits = IL->inits();
9714 // Deduction only works if we have exactly one source expression.
9715 if (DeduceInits.empty()) {
9716 // It isn't possible to write this directly, but it is possible to
9717 // end up in this situation with "auto x(some_pack...);"
9718 Diag(Init->getLocStart(), IsInitCapture
9719 ? diag::err_init_capture_no_expression
9720 : diag::err_auto_var_init_no_expression)
9721 << VN << Type << Range;
9725 if (DeduceInits.size() > 1) {
9726 Diag(DeduceInits[1]->getLocStart(),
9727 IsInitCapture ? diag::err_init_capture_multiple_expressions
9728 : diag::err_auto_var_init_multiple_expressions)
9729 << VN << Type << Range;
9733 Expr *DeduceInit = DeduceInits[0];
9734 if (DirectInit && isa<InitListExpr>(DeduceInit)) {
9735 Diag(Init->getLocStart(), IsInitCapture
9736 ? diag::err_init_capture_paren_braces
9737 : diag::err_auto_var_init_paren_braces)
9738 << isa<InitListExpr>(Init) << VN << Type << Range;
9742 // Expressions default to 'id' when we're in a debugger.
9743 bool DefaultedAnyToId = false;
9744 if (getLangOpts().DebuggerCastResultToId &&
9745 Init->getType() == Context.UnknownAnyTy && !IsInitCapture) {
9746 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
9747 if (Result.isInvalid()) {
9750 Init = Result.get();
9751 DefaultedAnyToId = true;
9754 // C++ [dcl.decomp]p1:
9755 // If the assignment-expression [...] has array type A and no ref-qualifier
9756 // is present, e has type cv A
9757 if (VDecl && isa<DecompositionDecl>(VDecl) &&
9758 Context.hasSameUnqualifiedType(Type, Context.getAutoDeductType()) &&
9759 DeduceInit->getType()->isConstantArrayType())
9760 return Context.getQualifiedType(DeduceInit->getType(),
9761 Type.getQualifiers());
9763 QualType DeducedType;
9764 if (DeduceAutoType(TSI, DeduceInit, DeducedType) == DAR_Failed) {
9766 DiagnoseAutoDeductionFailure(VDecl, DeduceInit);
9767 else if (isa<InitListExpr>(Init))
9768 Diag(Range.getBegin(),
9769 diag::err_init_capture_deduction_failure_from_init_list)
9771 << (DeduceInit->getType().isNull() ? TSI->getType()
9772 : DeduceInit->getType())
9773 << DeduceInit->getSourceRange();
9775 Diag(Range.getBegin(), diag::err_init_capture_deduction_failure)
9776 << VN << TSI->getType()
9777 << (DeduceInit->getType().isNull() ? TSI->getType()
9778 : DeduceInit->getType())
9779 << DeduceInit->getSourceRange();
9782 // Warn if we deduced 'id'. 'auto' usually implies type-safety, but using
9783 // 'id' instead of a specific object type prevents most of our usual
9785 // We only want to warn outside of template instantiations, though:
9786 // inside a template, the 'id' could have come from a parameter.
9787 if (ActiveTemplateInstantiations.empty() && !DefaultedAnyToId &&
9788 !IsInitCapture && !DeducedType.isNull() && DeducedType->isObjCIdType()) {
9789 SourceLocation Loc = TSI->getTypeLoc().getBeginLoc();
9790 Diag(Loc, diag::warn_auto_var_is_id) << VN << Range;
9796 /// AddInitializerToDecl - Adds the initializer Init to the
9797 /// declaration dcl. If DirectInit is true, this is C++ direct
9798 /// initialization rather than copy initialization.
9799 void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit) {
9800 // If there is no declaration, there was an error parsing it. Just ignore
9802 if (!RealDecl || RealDecl->isInvalidDecl()) {
9803 CorrectDelayedTyposInExpr(Init, dyn_cast_or_null<VarDecl>(RealDecl));
9807 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) {
9808 // Pure-specifiers are handled in ActOnPureSpecifier.
9809 Diag(Method->getLocation(), diag::err_member_function_initialization)
9810 << Method->getDeclName() << Init->getSourceRange();
9811 Method->setInvalidDecl();
9815 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl);
9817 assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here");
9818 Diag(RealDecl->getLocation(), diag::err_illegal_initializer);
9819 RealDecl->setInvalidDecl();
9823 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for.
9824 if (VDecl->getType()->isUndeducedType()) {
9825 // Attempt typo correction early so that the type of the init expression can
9826 // be deduced based on the chosen correction if the original init contains a
9828 ExprResult Res = CorrectDelayedTyposInExpr(Init, VDecl);
9829 if (!Res.isUsable()) {
9830 RealDecl->setInvalidDecl();
9835 QualType DeducedType = deduceVarTypeFromInitializer(
9836 VDecl, VDecl->getDeclName(), VDecl->getType(),
9837 VDecl->getTypeSourceInfo(), VDecl->getSourceRange(), DirectInit, Init);
9838 if (DeducedType.isNull()) {
9839 RealDecl->setInvalidDecl();
9843 VDecl->setType(DeducedType);
9844 assert(VDecl->isLinkageValid());
9846 // In ARC, infer lifetime.
9847 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(VDecl))
9848 VDecl->setInvalidDecl();
9850 // If this is a redeclaration, check that the type we just deduced matches
9851 // the previously declared type.
9852 if (VarDecl *Old = VDecl->getPreviousDecl()) {
9853 // We never need to merge the type, because we cannot form an incomplete
9854 // array of auto, nor deduce such a type.
9855 MergeVarDeclTypes(VDecl, Old, /*MergeTypeWithPrevious*/ false);
9858 // Check the deduced type is valid for a variable declaration.
9859 CheckVariableDeclarationType(VDecl);
9860 if (VDecl->isInvalidDecl())
9864 // dllimport cannot be used on variable definitions.
9865 if (VDecl->hasAttr<DLLImportAttr>() && !VDecl->isStaticDataMember()) {
9866 Diag(VDecl->getLocation(), diag::err_attribute_dllimport_data_definition);
9867 VDecl->setInvalidDecl();
9871 if (VDecl->isLocalVarDecl() && VDecl->hasExternalStorage()) {
9872 // C99 6.7.8p5. C++ has no such restriction, but that is a defect.
9873 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init);
9874 VDecl->setInvalidDecl();
9878 if (!VDecl->getType()->isDependentType()) {
9879 // A definition must end up with a complete type, which means it must be
9880 // complete with the restriction that an array type might be completed by
9881 // the initializer; note that later code assumes this restriction.
9882 QualType BaseDeclType = VDecl->getType();
9883 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType))
9884 BaseDeclType = Array->getElementType();
9885 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType,
9886 diag::err_typecheck_decl_incomplete_type)) {
9887 RealDecl->setInvalidDecl();
9891 // The variable can not have an abstract class type.
9892 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(),
9893 diag::err_abstract_type_in_decl,
9894 AbstractVariableType))
9895 VDecl->setInvalidDecl();
9898 // If adding the initializer will turn this declaration into a definition,
9899 // and we already have a definition for this variable, diagnose or otherwise
9900 // handle the situation.
9902 if ((Def = VDecl->getDefinition()) && Def != VDecl &&
9903 (!VDecl->isStaticDataMember() || VDecl->isOutOfLine()) &&
9904 !VDecl->isThisDeclarationADemotedDefinition() &&
9905 checkVarDeclRedefinition(Def, VDecl))
9908 if (getLangOpts().CPlusPlus) {
9909 // C++ [class.static.data]p4
9910 // If a static data member is of const integral or const
9911 // enumeration type, its declaration in the class definition can
9912 // specify a constant-initializer which shall be an integral
9913 // constant expression (5.19). In that case, the member can appear
9914 // in integral constant expressions. The member shall still be
9915 // defined in a namespace scope if it is used in the program and the
9916 // namespace scope definition shall not contain an initializer.
9918 // We already performed a redefinition check above, but for static
9919 // data members we also need to check whether there was an in-class
9920 // declaration with an initializer.
9921 if (VDecl->isStaticDataMember() && VDecl->getCanonicalDecl()->hasInit()) {
9922 Diag(Init->getExprLoc(), diag::err_static_data_member_reinitialization)
9923 << VDecl->getDeclName();
9924 Diag(VDecl->getCanonicalDecl()->getInit()->getExprLoc(),
9925 diag::note_previous_initializer)
9930 if (VDecl->hasLocalStorage())
9931 getCurFunction()->setHasBranchProtectedScope();
9933 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) {
9934 VDecl->setInvalidDecl();
9939 // OpenCL 1.1 6.5.2: "Variables allocated in the __local address space inside
9940 // a kernel function cannot be initialized."
9941 if (VDecl->getType().getAddressSpace() == LangAS::opencl_local) {
9942 Diag(VDecl->getLocation(), diag::err_local_cant_init);
9943 VDecl->setInvalidDecl();
9947 // Get the decls type and save a reference for later, since
9948 // CheckInitializerTypes may change it.
9949 QualType DclT = VDecl->getType(), SavT = DclT;
9951 // Expressions default to 'id' when we're in a debugger
9952 // and we are assigning it to a variable of Objective-C pointer type.
9953 if (getLangOpts().DebuggerCastResultToId && DclT->isObjCObjectPointerType() &&
9954 Init->getType() == Context.UnknownAnyTy) {
9955 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
9956 if (Result.isInvalid()) {
9957 VDecl->setInvalidDecl();
9960 Init = Result.get();
9963 // Perform the initialization.
9964 ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
9965 if (!VDecl->isInvalidDecl()) {
9966 // Handle errors like: int a({0})
9967 if (CXXDirectInit && CXXDirectInit->getNumExprs() == 1 &&
9968 !canInitializeWithParenthesizedList(VDecl->getType()))
9969 if (auto IList = dyn_cast<InitListExpr>(CXXDirectInit->getExpr(0))) {
9970 Diag(VDecl->getLocation(), diag::err_list_init_in_parens)
9971 << VDecl->getType() << CXXDirectInit->getSourceRange()
9972 << FixItHint::CreateRemoval(CXXDirectInit->getLocStart())
9973 << FixItHint::CreateRemoval(CXXDirectInit->getLocEnd());
9975 CXXDirectInit = nullptr;
9978 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
9979 InitializationKind Kind =
9982 ? InitializationKind::CreateDirect(VDecl->getLocation(),
9983 Init->getLocStart(),
9985 : InitializationKind::CreateDirectList(VDecl->getLocation())
9986 : InitializationKind::CreateCopy(VDecl->getLocation(),
9987 Init->getLocStart());
9989 MultiExprArg Args = Init;
9991 Args = MultiExprArg(CXXDirectInit->getExprs(),
9992 CXXDirectInit->getNumExprs());
9994 // Try to correct any TypoExprs in the initialization arguments.
9995 for (size_t Idx = 0; Idx < Args.size(); ++Idx) {
9996 ExprResult Res = CorrectDelayedTyposInExpr(
9997 Args[Idx], VDecl, [this, Entity, Kind](Expr *E) {
9998 InitializationSequence Init(*this, Entity, Kind, MultiExprArg(E));
9999 return Init.Failed() ? ExprError() : E;
10001 if (Res.isInvalid()) {
10002 VDecl->setInvalidDecl();
10003 } else if (Res.get() != Args[Idx]) {
10004 Args[Idx] = Res.get();
10007 if (VDecl->isInvalidDecl())
10010 InitializationSequence InitSeq(*this, Entity, Kind, Args,
10011 /*TopLevelOfInitList=*/false,
10012 /*TreatUnavailableAsInvalid=*/false);
10013 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
10014 if (Result.isInvalid()) {
10015 VDecl->setInvalidDecl();
10019 Init = Result.getAs<Expr>();
10022 // Check for self-references within variable initializers.
10023 // Variables declared within a function/method body (except for references)
10024 // are handled by a dataflow analysis.
10025 if (!VDecl->hasLocalStorage() || VDecl->getType()->isRecordType() ||
10026 VDecl->getType()->isReferenceType()) {
10027 CheckSelfReference(*this, RealDecl, Init, DirectInit);
10030 // If the type changed, it means we had an incomplete type that was
10031 // completed by the initializer. For example:
10032 // int ary[] = { 1, 3, 5 };
10033 // "ary" transitions from an IncompleteArrayType to a ConstantArrayType.
10034 if (!VDecl->isInvalidDecl() && (DclT != SavT))
10035 VDecl->setType(DclT);
10037 if (!VDecl->isInvalidDecl()) {
10038 checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init);
10040 if (VDecl->hasAttr<BlocksAttr>())
10041 checkRetainCycles(VDecl, Init);
10043 // It is safe to assign a weak reference into a strong variable.
10044 // Although this code can still have problems:
10045 // id x = self.weakProp;
10046 // id y = self.weakProp;
10047 // we do not warn to warn spuriously when 'x' and 'y' are on separate
10048 // paths through the function. This should be revisited if
10049 // -Wrepeated-use-of-weak is made flow-sensitive.
10050 if (VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong &&
10051 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
10052 Init->getLocStart()))
10053 getCurFunction()->markSafeWeakUse(Init);
10056 // The initialization is usually a full-expression.
10058 // FIXME: If this is a braced initialization of an aggregate, it is not
10059 // an expression, and each individual field initializer is a separate
10060 // full-expression. For instance, in:
10062 // struct Temp { ~Temp(); };
10063 // struct S { S(Temp); };
10064 // struct T { S a, b; } t = { Temp(), Temp() }
10066 // we should destroy the first Temp before constructing the second.
10067 ExprResult Result = ActOnFinishFullExpr(Init, VDecl->getLocation(),
10069 VDecl->isConstexpr());
10070 if (Result.isInvalid()) {
10071 VDecl->setInvalidDecl();
10074 Init = Result.get();
10076 // Attach the initializer to the decl.
10077 VDecl->setInit(Init);
10079 if (VDecl->isLocalVarDecl()) {
10080 // C99 6.7.8p4: All the expressions in an initializer for an object that has
10081 // static storage duration shall be constant expressions or string literals.
10082 // C++ does not have this restriction.
10083 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl()) {
10084 const Expr *Culprit;
10085 if (VDecl->getStorageClass() == SC_Static)
10086 CheckForConstantInitializer(Init, DclT);
10087 // C89 is stricter than C99 for non-static aggregate types.
10088 // C89 6.5.7p3: All the expressions [...] in an initializer list
10089 // for an object that has aggregate or union type shall be
10090 // constant expressions.
10091 else if (!getLangOpts().C99 && VDecl->getType()->isAggregateType() &&
10092 isa<InitListExpr>(Init) &&
10093 !Init->isConstantInitializer(Context, false, &Culprit))
10094 Diag(Culprit->getExprLoc(),
10095 diag::ext_aggregate_init_not_constant)
10096 << Culprit->getSourceRange();
10098 } else if (VDecl->isStaticDataMember() && !VDecl->isInline() &&
10099 VDecl->getLexicalDeclContext()->isRecord()) {
10100 // This is an in-class initialization for a static data member, e.g.,
10103 // static const int value = 17;
10106 // C++ [class.mem]p4:
10107 // A member-declarator can contain a constant-initializer only
10108 // if it declares a static member (9.4) of const integral or
10109 // const enumeration type, see 9.4.2.
10111 // C++11 [class.static.data]p3:
10112 // If a non-volatile non-inline const static data member is of integral
10113 // or enumeration type, its declaration in the class definition can
10114 // specify a brace-or-equal-initializer in which every initalizer-clause
10115 // that is an assignment-expression is a constant expression. A static
10116 // data member of literal type can be declared in the class definition
10117 // with the constexpr specifier; if so, its declaration shall specify a
10118 // brace-or-equal-initializer in which every initializer-clause that is
10119 // an assignment-expression is a constant expression.
10121 // Do nothing on dependent types.
10122 if (DclT->isDependentType()) {
10124 // Allow any 'static constexpr' members, whether or not they are of literal
10125 // type. We separately check that every constexpr variable is of literal
10127 } else if (VDecl->isConstexpr()) {
10129 // Require constness.
10130 } else if (!DclT.isConstQualified()) {
10131 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const)
10132 << Init->getSourceRange();
10133 VDecl->setInvalidDecl();
10135 // We allow integer constant expressions in all cases.
10136 } else if (DclT->isIntegralOrEnumerationType()) {
10137 // Check whether the expression is a constant expression.
10138 SourceLocation Loc;
10139 if (getLangOpts().CPlusPlus11 && DclT.isVolatileQualified())
10140 // In C++11, a non-constexpr const static data member with an
10141 // in-class initializer cannot be volatile.
10142 Diag(VDecl->getLocation(), diag::err_in_class_initializer_volatile);
10143 else if (Init->isValueDependent())
10144 ; // Nothing to check.
10145 else if (Init->isIntegerConstantExpr(Context, &Loc))
10146 ; // Ok, it's an ICE!
10147 else if (Init->isEvaluatable(Context)) {
10148 // If we can constant fold the initializer through heroics, accept it,
10149 // but report this as a use of an extension for -pedantic.
10150 Diag(Loc, diag::ext_in_class_initializer_non_constant)
10151 << Init->getSourceRange();
10153 // Otherwise, this is some crazy unknown case. Report the issue at the
10154 // location provided by the isIntegerConstantExpr failed check.
10155 Diag(Loc, diag::err_in_class_initializer_non_constant)
10156 << Init->getSourceRange();
10157 VDecl->setInvalidDecl();
10160 // We allow foldable floating-point constants as an extension.
10161 } else if (DclT->isFloatingType()) { // also permits complex, which is ok
10162 // In C++98, this is a GNU extension. In C++11, it is not, but we support
10163 // it anyway and provide a fixit to add the 'constexpr'.
10164 if (getLangOpts().CPlusPlus11) {
10165 Diag(VDecl->getLocation(),
10166 diag::ext_in_class_initializer_float_type_cxx11)
10167 << DclT << Init->getSourceRange();
10168 Diag(VDecl->getLocStart(),
10169 diag::note_in_class_initializer_float_type_cxx11)
10170 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
10172 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type)
10173 << DclT << Init->getSourceRange();
10175 if (!Init->isValueDependent() && !Init->isEvaluatable(Context)) {
10176 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant)
10177 << Init->getSourceRange();
10178 VDecl->setInvalidDecl();
10182 // Suggest adding 'constexpr' in C++11 for literal types.
10183 } else if (getLangOpts().CPlusPlus11 && DclT->isLiteralType(Context)) {
10184 Diag(VDecl->getLocation(), diag::err_in_class_initializer_literal_type)
10185 << DclT << Init->getSourceRange()
10186 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
10187 VDecl->setConstexpr(true);
10190 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type)
10191 << DclT << Init->getSourceRange();
10192 VDecl->setInvalidDecl();
10194 } else if (VDecl->isFileVarDecl()) {
10195 // In C, extern is typically used to avoid tentative definitions when
10196 // declaring variables in headers, but adding an intializer makes it a
10197 // defintion. This is somewhat confusing, so GCC and Clang both warn on it.
10198 // In C++, extern is often used to give implictly static const variables
10199 // external linkage, so don't warn in that case. If selectany is present,
10200 // this might be header code intended for C and C++ inclusion, so apply the
10202 if (VDecl->getStorageClass() == SC_Extern &&
10203 ((!getLangOpts().CPlusPlus && !VDecl->hasAttr<SelectAnyAttr>()) ||
10204 !Context.getBaseElementType(VDecl->getType()).isConstQualified()) &&
10205 !(getLangOpts().CPlusPlus && VDecl->isExternC()) &&
10206 !isTemplateInstantiation(VDecl->getTemplateSpecializationKind()))
10207 Diag(VDecl->getLocation(), diag::warn_extern_init);
10209 // C99 6.7.8p4. All file scoped initializers need to be constant.
10210 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl())
10211 CheckForConstantInitializer(Init, DclT);
10214 // We will represent direct-initialization similarly to copy-initialization:
10215 // int x(1); -as-> int x = 1;
10216 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c);
10218 // Clients that want to distinguish between the two forms, can check for
10219 // direct initializer using VarDecl::getInitStyle().
10220 // A major benefit is that clients that don't particularly care about which
10221 // exactly form was it (like the CodeGen) can handle both cases without
10222 // special case code.
10225 // The form of initialization (using parentheses or '=') is generally
10226 // insignificant, but does matter when the entity being initialized has a
10228 if (CXXDirectInit) {
10229 assert(DirectInit && "Call-style initializer must be direct init.");
10230 VDecl->setInitStyle(VarDecl::CallInit);
10231 } else if (DirectInit) {
10232 // This must be list-initialization. No other way is direct-initialization.
10233 VDecl->setInitStyle(VarDecl::ListInit);
10236 CheckCompleteVariableDeclaration(VDecl);
10239 /// ActOnInitializerError - Given that there was an error parsing an
10240 /// initializer for the given declaration, try to return to some form
10242 void Sema::ActOnInitializerError(Decl *D) {
10243 // Our main concern here is re-establishing invariants like "a
10244 // variable's type is either dependent or complete".
10245 if (!D || D->isInvalidDecl()) return;
10247 VarDecl *VD = dyn_cast<VarDecl>(D);
10250 // Bindings are not usable if we can't make sense of the initializer.
10251 if (auto *DD = dyn_cast<DecompositionDecl>(D))
10252 for (auto *BD : DD->bindings())
10253 BD->setInvalidDecl();
10255 // Auto types are meaningless if we can't make sense of the initializer.
10256 if (ParsingInitForAutoVars.count(D)) {
10257 D->setInvalidDecl();
10261 QualType Ty = VD->getType();
10262 if (Ty->isDependentType()) return;
10264 // Require a complete type.
10265 if (RequireCompleteType(VD->getLocation(),
10266 Context.getBaseElementType(Ty),
10267 diag::err_typecheck_decl_incomplete_type)) {
10268 VD->setInvalidDecl();
10272 // Require a non-abstract type.
10273 if (RequireNonAbstractType(VD->getLocation(), Ty,
10274 diag::err_abstract_type_in_decl,
10275 AbstractVariableType)) {
10276 VD->setInvalidDecl();
10280 // Don't bother complaining about constructors or destructors,
10284 /// Checks if an object of the given type can be initialized with parenthesized
10287 /// \param TargetType Type of object being initialized.
10289 /// The function is used to detect wrong initializations, such as 'int({0})'.
10291 bool Sema::canInitializeWithParenthesizedList(QualType TargetType) {
10292 return TargetType->isDependentType() || TargetType->isRecordType() ||
10293 TargetType->getContainedAutoType();
10296 void Sema::ActOnUninitializedDecl(Decl *RealDecl) {
10297 // If there is no declaration, there was an error parsing it. Just ignore it.
10301 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) {
10302 QualType Type = Var->getType();
10304 // C++1z [dcl.dcl]p1 grammar implies that an initializer is mandatory.
10305 if (isa<DecompositionDecl>(RealDecl)) {
10306 Diag(Var->getLocation(), diag::err_decomp_decl_requires_init) << Var;
10307 Var->setInvalidDecl();
10311 // C++11 [dcl.spec.auto]p3
10312 if (Type->isUndeducedType()) {
10313 Diag(Var->getLocation(), diag::err_auto_var_requires_init)
10314 << Var->getDeclName() << Type;
10315 Var->setInvalidDecl();
10319 // C++11 [class.static.data]p3: A static data member can be declared with
10320 // the constexpr specifier; if so, its declaration shall specify
10321 // a brace-or-equal-initializer.
10322 // C++11 [dcl.constexpr]p1: The constexpr specifier shall be applied only to
10323 // the definition of a variable [...] or the declaration of a static data
10325 if (Var->isConstexpr() && !Var->isThisDeclarationADefinition() &&
10326 !Var->isThisDeclarationADemotedDefinition()) {
10327 if (Var->isStaticDataMember()) {
10328 // C++1z removes the relevant rule; the in-class declaration is always
10329 // a definition there.
10330 if (!getLangOpts().CPlusPlus1z) {
10331 Diag(Var->getLocation(),
10332 diag::err_constexpr_static_mem_var_requires_init)
10333 << Var->getDeclName();
10334 Var->setInvalidDecl();
10338 Diag(Var->getLocation(), diag::err_invalid_constexpr_var_decl);
10339 Var->setInvalidDecl();
10344 // C++ Concepts TS [dcl.spec.concept]p1: [...] A variable template
10345 // definition having the concept specifier is called a variable concept. A
10346 // concept definition refers to [...] a variable concept and its initializer.
10347 if (VarTemplateDecl *VTD = Var->getDescribedVarTemplate()) {
10348 if (VTD->isConcept()) {
10349 Diag(Var->getLocation(), diag::err_var_concept_not_initialized);
10350 Var->setInvalidDecl();
10355 // OpenCL v1.1 s6.5.3: variables declared in the constant address space must
10357 if (!Var->isInvalidDecl() &&
10358 Var->getType().getAddressSpace() == LangAS::opencl_constant &&
10359 Var->getStorageClass() != SC_Extern && !Var->getInit()) {
10360 Diag(Var->getLocation(), diag::err_opencl_constant_no_init);
10361 Var->setInvalidDecl();
10365 switch (Var->isThisDeclarationADefinition()) {
10366 case VarDecl::Definition:
10367 if (!Var->isStaticDataMember() || !Var->getAnyInitializer())
10370 // We have an out-of-line definition of a static data member
10371 // that has an in-class initializer, so we type-check this like
10376 case VarDecl::DeclarationOnly:
10377 // It's only a declaration.
10379 // Block scope. C99 6.7p7: If an identifier for an object is
10380 // declared with no linkage (C99 6.2.2p6), the type for the
10381 // object shall be complete.
10382 if (!Type->isDependentType() && Var->isLocalVarDecl() &&
10383 !Var->hasLinkage() && !Var->isInvalidDecl() &&
10384 RequireCompleteType(Var->getLocation(), Type,
10385 diag::err_typecheck_decl_incomplete_type))
10386 Var->setInvalidDecl();
10388 // Make sure that the type is not abstract.
10389 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
10390 RequireNonAbstractType(Var->getLocation(), Type,
10391 diag::err_abstract_type_in_decl,
10392 AbstractVariableType))
10393 Var->setInvalidDecl();
10394 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
10395 Var->getStorageClass() == SC_PrivateExtern) {
10396 Diag(Var->getLocation(), diag::warn_private_extern);
10397 Diag(Var->getLocation(), diag::note_private_extern);
10402 case VarDecl::TentativeDefinition:
10403 // File scope. C99 6.9.2p2: A declaration of an identifier for an
10404 // object that has file scope without an initializer, and without a
10405 // storage-class specifier or with the storage-class specifier "static",
10406 // constitutes a tentative definition. Note: A tentative definition with
10407 // external linkage is valid (C99 6.2.2p5).
10408 if (!Var->isInvalidDecl()) {
10409 if (const IncompleteArrayType *ArrayT
10410 = Context.getAsIncompleteArrayType(Type)) {
10411 if (RequireCompleteType(Var->getLocation(),
10412 ArrayT->getElementType(),
10413 diag::err_illegal_decl_array_incomplete_type))
10414 Var->setInvalidDecl();
10415 } else if (Var->getStorageClass() == SC_Static) {
10416 // C99 6.9.2p3: If the declaration of an identifier for an object is
10417 // a tentative definition and has internal linkage (C99 6.2.2p3), the
10418 // declared type shall not be an incomplete type.
10419 // NOTE: code such as the following
10420 // static struct s;
10421 // struct s { int a; };
10422 // is accepted by gcc. Hence here we issue a warning instead of
10423 // an error and we do not invalidate the static declaration.
10424 // NOTE: to avoid multiple warnings, only check the first declaration.
10425 if (Var->isFirstDecl())
10426 RequireCompleteType(Var->getLocation(), Type,
10427 diag::ext_typecheck_decl_incomplete_type);
10431 // Record the tentative definition; we're done.
10432 if (!Var->isInvalidDecl())
10433 TentativeDefinitions.push_back(Var);
10437 // Provide a specific diagnostic for uninitialized variable
10438 // definitions with incomplete array type.
10439 if (Type->isIncompleteArrayType()) {
10440 Diag(Var->getLocation(),
10441 diag::err_typecheck_incomplete_array_needs_initializer);
10442 Var->setInvalidDecl();
10446 // Provide a specific diagnostic for uninitialized variable
10447 // definitions with reference type.
10448 if (Type->isReferenceType()) {
10449 Diag(Var->getLocation(), diag::err_reference_var_requires_init)
10450 << Var->getDeclName()
10451 << SourceRange(Var->getLocation(), Var->getLocation());
10452 Var->setInvalidDecl();
10456 // Do not attempt to type-check the default initializer for a
10457 // variable with dependent type.
10458 if (Type->isDependentType())
10461 if (Var->isInvalidDecl())
10464 if (!Var->hasAttr<AliasAttr>()) {
10465 if (RequireCompleteType(Var->getLocation(),
10466 Context.getBaseElementType(Type),
10467 diag::err_typecheck_decl_incomplete_type)) {
10468 Var->setInvalidDecl();
10475 // The variable can not have an abstract class type.
10476 if (RequireNonAbstractType(Var->getLocation(), Type,
10477 diag::err_abstract_type_in_decl,
10478 AbstractVariableType)) {
10479 Var->setInvalidDecl();
10483 // Check for jumps past the implicit initializer. C++0x
10484 // clarifies that this applies to a "variable with automatic
10485 // storage duration", not a "local variable".
10486 // C++11 [stmt.dcl]p3
10487 // A program that jumps from a point where a variable with automatic
10488 // storage duration is not in scope to a point where it is in scope is
10489 // ill-formed unless the variable has scalar type, class type with a
10490 // trivial default constructor and a trivial destructor, a cv-qualified
10491 // version of one of these types, or an array of one of the preceding
10492 // types and is declared without an initializer.
10493 if (getLangOpts().CPlusPlus && Var->hasLocalStorage()) {
10494 if (const RecordType *Record
10495 = Context.getBaseElementType(Type)->getAs<RecordType>()) {
10496 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl());
10497 // Mark the function for further checking even if the looser rules of
10498 // C++11 do not require such checks, so that we can diagnose
10499 // incompatibilities with C++98.
10500 if (!CXXRecord->isPOD())
10501 getCurFunction()->setHasBranchProtectedScope();
10505 // C++03 [dcl.init]p9:
10506 // If no initializer is specified for an object, and the
10507 // object is of (possibly cv-qualified) non-POD class type (or
10508 // array thereof), the object shall be default-initialized; if
10509 // the object is of const-qualified type, the underlying class
10510 // type shall have a user-declared default
10511 // constructor. Otherwise, if no initializer is specified for
10512 // a non- static object, the object and its subobjects, if
10513 // any, have an indeterminate initial value); if the object
10514 // or any of its subobjects are of const-qualified type, the
10515 // program is ill-formed.
10516 // C++0x [dcl.init]p11:
10517 // If no initializer is specified for an object, the object is
10518 // default-initialized; [...].
10519 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var);
10520 InitializationKind Kind
10521 = InitializationKind::CreateDefault(Var->getLocation());
10523 InitializationSequence InitSeq(*this, Entity, Kind, None);
10524 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, None);
10525 if (Init.isInvalid())
10526 Var->setInvalidDecl();
10527 else if (Init.get()) {
10528 Var->setInit(MaybeCreateExprWithCleanups(Init.get()));
10529 // This is important for template substitution.
10530 Var->setInitStyle(VarDecl::CallInit);
10533 CheckCompleteVariableDeclaration(Var);
10537 void Sema::ActOnCXXForRangeDecl(Decl *D) {
10538 // If there is no declaration, there was an error parsing it. Ignore it.
10542 VarDecl *VD = dyn_cast<VarDecl>(D);
10544 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var);
10545 D->setInvalidDecl();
10549 VD->setCXXForRangeDecl(true);
10551 // for-range-declaration cannot be given a storage class specifier.
10553 switch (VD->getStorageClass()) {
10562 case SC_PrivateExtern:
10573 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class)
10574 << VD->getDeclName() << Error;
10575 D->setInvalidDecl();
10580 Sema::ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
10581 IdentifierInfo *Ident,
10582 ParsedAttributes &Attrs,
10583 SourceLocation AttrEnd) {
10584 // C++1y [stmt.iter]p1:
10585 // A range-based for statement of the form
10586 // for ( for-range-identifier : for-range-initializer ) statement
10587 // is equivalent to
10588 // for ( auto&& for-range-identifier : for-range-initializer ) statement
10589 DeclSpec DS(Attrs.getPool().getFactory());
10591 const char *PrevSpec;
10593 DS.SetTypeSpecType(DeclSpec::TST_auto, IdentLoc, PrevSpec, DiagID,
10594 getPrintingPolicy());
10596 Declarator D(DS, Declarator::ForContext);
10597 D.SetIdentifier(Ident, IdentLoc);
10598 D.takeAttributes(Attrs, AttrEnd);
10600 ParsedAttributes EmptyAttrs(Attrs.getPool().getFactory());
10601 D.AddTypeInfo(DeclaratorChunk::getReference(0, IdentLoc, /*lvalue*/false),
10602 EmptyAttrs, IdentLoc);
10603 Decl *Var = ActOnDeclarator(S, D);
10604 cast<VarDecl>(Var)->setCXXForRangeDecl(true);
10605 FinalizeDeclaration(Var);
10606 return ActOnDeclStmt(FinalizeDeclaratorGroup(S, DS, Var), IdentLoc,
10607 AttrEnd.isValid() ? AttrEnd : IdentLoc);
10610 void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
10611 if (var->isInvalidDecl()) return;
10613 if (getLangOpts().OpenCL) {
10614 // OpenCL v2.0 s6.12.5 - Every block variable declaration must have an
10616 if (var->getTypeSourceInfo()->getType()->isBlockPointerType() &&
10618 Diag(var->getLocation(), diag::err_opencl_invalid_block_declaration)
10620 var->setInvalidDecl();
10625 // In Objective-C, don't allow jumps past the implicit initialization of a
10626 // local retaining variable.
10627 if (getLangOpts().ObjC1 &&
10628 var->hasLocalStorage()) {
10629 switch (var->getType().getObjCLifetime()) {
10630 case Qualifiers::OCL_None:
10631 case Qualifiers::OCL_ExplicitNone:
10632 case Qualifiers::OCL_Autoreleasing:
10635 case Qualifiers::OCL_Weak:
10636 case Qualifiers::OCL_Strong:
10637 getCurFunction()->setHasBranchProtectedScope();
10642 // Warn about externally-visible variables being defined without a
10643 // prior declaration. We only want to do this for global
10644 // declarations, but we also specifically need to avoid doing it for
10645 // class members because the linkage of an anonymous class can
10646 // change if it's later given a typedef name.
10647 if (var->isThisDeclarationADefinition() &&
10648 var->getDeclContext()->getRedeclContext()->isFileContext() &&
10649 var->isExternallyVisible() && var->hasLinkage() &&
10650 !getDiagnostics().isIgnored(diag::warn_missing_variable_declarations,
10651 var->getLocation())) {
10652 // Find a previous declaration that's not a definition.
10653 VarDecl *prev = var->getPreviousDecl();
10654 while (prev && prev->isThisDeclarationADefinition())
10655 prev = prev->getPreviousDecl();
10658 Diag(var->getLocation(), diag::warn_missing_variable_declarations) << var;
10661 // Cache the result of checking for constant initialization.
10662 Optional<bool> CacheHasConstInit;
10663 const Expr *CacheCulprit;
10664 auto checkConstInit = [&]() mutable {
10665 if (!CacheHasConstInit)
10666 CacheHasConstInit = var->getInit()->isConstantInitializer(
10667 Context, var->getType()->isReferenceType(), &CacheCulprit);
10668 return *CacheHasConstInit;
10671 if (var->getTLSKind() == VarDecl::TLS_Static) {
10672 if (var->getType().isDestructedType()) {
10673 // GNU C++98 edits for __thread, [basic.start.term]p3:
10674 // The type of an object with thread storage duration shall not
10675 // have a non-trivial destructor.
10676 Diag(var->getLocation(), diag::err_thread_nontrivial_dtor);
10677 if (getLangOpts().CPlusPlus11)
10678 Diag(var->getLocation(), diag::note_use_thread_local);
10679 } else if (getLangOpts().CPlusPlus && var->hasInit()) {
10680 if (!checkConstInit()) {
10681 // GNU C++98 edits for __thread, [basic.start.init]p4:
10682 // An object of thread storage duration shall not require dynamic
10684 // FIXME: Need strict checking here.
10685 Diag(CacheCulprit->getExprLoc(), diag::err_thread_dynamic_init)
10686 << CacheCulprit->getSourceRange();
10687 if (getLangOpts().CPlusPlus11)
10688 Diag(var->getLocation(), diag::note_use_thread_local);
10693 // Apply section attributes and pragmas to global variables.
10694 bool GlobalStorage = var->hasGlobalStorage();
10695 if (GlobalStorage && var->isThisDeclarationADefinition() &&
10696 ActiveTemplateInstantiations.empty()) {
10697 PragmaStack<StringLiteral *> *Stack = nullptr;
10698 int SectionFlags = ASTContext::PSF_Implicit | ASTContext::PSF_Read;
10699 if (var->getType().isConstQualified())
10700 Stack = &ConstSegStack;
10701 else if (!var->getInit()) {
10702 Stack = &BSSSegStack;
10703 SectionFlags |= ASTContext::PSF_Write;
10705 Stack = &DataSegStack;
10706 SectionFlags |= ASTContext::PSF_Write;
10708 if (Stack->CurrentValue && !var->hasAttr<SectionAttr>()) {
10709 var->addAttr(SectionAttr::CreateImplicit(
10710 Context, SectionAttr::Declspec_allocate,
10711 Stack->CurrentValue->getString(), Stack->CurrentPragmaLocation));
10713 if (const SectionAttr *SA = var->getAttr<SectionAttr>())
10714 if (UnifySection(SA->getName(), SectionFlags, var))
10715 var->dropAttr<SectionAttr>();
10717 // Apply the init_seg attribute if this has an initializer. If the
10718 // initializer turns out to not be dynamic, we'll end up ignoring this
10720 if (CurInitSeg && var->getInit())
10721 var->addAttr(InitSegAttr::CreateImplicit(Context, CurInitSeg->getString(),
10725 // All the following checks are C++ only.
10726 if (!getLangOpts().CPlusPlus) {
10727 // If this variable must be emitted, add it as an initializer for the
10729 if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
10730 Context.addModuleInitializer(ModuleScopes.back().Module, var);
10734 if (auto *DD = dyn_cast<DecompositionDecl>(var))
10735 CheckCompleteDecompositionDeclaration(DD);
10737 QualType type = var->getType();
10738 if (type->isDependentType()) return;
10740 // __block variables might require us to capture a copy-initializer.
10741 if (var->hasAttr<BlocksAttr>()) {
10742 // It's currently invalid to ever have a __block variable with an
10743 // array type; should we diagnose that here?
10745 // Regardless, we don't want to ignore array nesting when
10746 // constructing this copy.
10747 if (type->isStructureOrClassType()) {
10748 EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
10749 SourceLocation poi = var->getLocation();
10750 Expr *varRef =new (Context) DeclRefExpr(var, false, type, VK_LValue, poi);
10752 = PerformMoveOrCopyInitialization(
10753 InitializedEntity::InitializeBlock(poi, type, false),
10754 var, var->getType(), varRef, /*AllowNRVO=*/true);
10755 if (!result.isInvalid()) {
10756 result = MaybeCreateExprWithCleanups(result);
10757 Expr *init = result.getAs<Expr>();
10758 Context.setBlockVarCopyInits(var, init);
10763 Expr *Init = var->getInit();
10764 bool IsGlobal = GlobalStorage && !var->isStaticLocal();
10765 QualType baseType = Context.getBaseElementType(type);
10767 if (!var->getDeclContext()->isDependentContext() &&
10768 Init && !Init->isValueDependent()) {
10770 if (var->isConstexpr()) {
10771 SmallVector<PartialDiagnosticAt, 8> Notes;
10772 if (!var->evaluateValue(Notes) || !var->isInitICE()) {
10773 SourceLocation DiagLoc = var->getLocation();
10774 // If the note doesn't add any useful information other than a source
10775 // location, fold it into the primary diagnostic.
10776 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
10777 diag::note_invalid_subexpr_in_const_expr) {
10778 DiagLoc = Notes[0].first;
10781 Diag(DiagLoc, diag::err_constexpr_var_requires_const_init)
10782 << var << Init->getSourceRange();
10783 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
10784 Diag(Notes[I].first, Notes[I].second);
10786 } else if (var->isUsableInConstantExpressions(Context)) {
10787 // Check whether the initializer of a const variable of integral or
10788 // enumeration type is an ICE now, since we can't tell whether it was
10789 // initialized by a constant expression if we check later.
10790 var->checkInitIsICE();
10793 // Don't emit further diagnostics about constexpr globals since they
10794 // were just diagnosed.
10795 if (!var->isConstexpr() && GlobalStorage &&
10796 var->hasAttr<RequireConstantInitAttr>()) {
10797 // FIXME: Need strict checking in C++03 here.
10798 bool DiagErr = getLangOpts().CPlusPlus11
10799 ? !var->checkInitIsICE() : !checkConstInit();
10801 auto attr = var->getAttr<RequireConstantInitAttr>();
10802 Diag(var->getLocation(), diag::err_require_constant_init_failed)
10803 << Init->getSourceRange();
10804 Diag(attr->getLocation(), diag::note_declared_required_constant_init_here)
10805 << attr->getRange();
10808 else if (!var->isConstexpr() && IsGlobal &&
10809 !getDiagnostics().isIgnored(diag::warn_global_constructor,
10810 var->getLocation())) {
10811 // Warn about globals which don't have a constant initializer. Don't
10812 // warn about globals with a non-trivial destructor because we already
10813 // warned about them.
10814 CXXRecordDecl *RD = baseType->getAsCXXRecordDecl();
10815 if (!(RD && !RD->hasTrivialDestructor())) {
10816 if (!checkConstInit())
10817 Diag(var->getLocation(), diag::warn_global_constructor)
10818 << Init->getSourceRange();
10823 // Require the destructor.
10824 if (const RecordType *recordType = baseType->getAs<RecordType>())
10825 FinalizeVarWithDestructor(var, recordType);
10827 // If this variable must be emitted, add it as an initializer for the current
10829 if (Context.DeclMustBeEmitted(var) && !ModuleScopes.empty())
10830 Context.addModuleInitializer(ModuleScopes.back().Module, var);
10833 /// \brief Determines if a variable's alignment is dependent.
10834 static bool hasDependentAlignment(VarDecl *VD) {
10835 if (VD->getType()->isDependentType())
10837 for (auto *I : VD->specific_attrs<AlignedAttr>())
10838 if (I->isAlignmentDependent())
10843 /// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform
10844 /// any semantic actions necessary after any initializer has been attached.
10846 Sema::FinalizeDeclaration(Decl *ThisDecl) {
10847 // Note that we are no longer parsing the initializer for this declaration.
10848 ParsingInitForAutoVars.erase(ThisDecl);
10850 VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDecl);
10854 if (auto *DD = dyn_cast<DecompositionDecl>(ThisDecl)) {
10855 for (auto *BD : DD->bindings()) {
10856 FinalizeDeclaration(BD);
10860 checkAttributesAfterMerging(*this, *VD);
10862 // Perform TLS alignment check here after attributes attached to the variable
10863 // which may affect the alignment have been processed. Only perform the check
10864 // if the target has a maximum TLS alignment (zero means no constraints).
10865 if (unsigned MaxAlign = Context.getTargetInfo().getMaxTLSAlign()) {
10866 // Protect the check so that it's not performed on dependent types and
10867 // dependent alignments (we can't determine the alignment in that case).
10868 if (VD->getTLSKind() && !hasDependentAlignment(VD)) {
10869 CharUnits MaxAlignChars = Context.toCharUnitsFromBits(MaxAlign);
10870 if (Context.getDeclAlign(VD) > MaxAlignChars) {
10871 Diag(VD->getLocation(), diag::err_tls_var_aligned_over_maximum)
10872 << (unsigned)Context.getDeclAlign(VD).getQuantity() << VD
10873 << (unsigned)MaxAlignChars.getQuantity();
10878 if (VD->isStaticLocal()) {
10879 if (FunctionDecl *FD =
10880 dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod())) {
10881 // Static locals inherit dll attributes from their function.
10882 if (Attr *A = getDLLAttr(FD)) {
10883 auto *NewAttr = cast<InheritableAttr>(A->clone(getASTContext()));
10884 NewAttr->setInherited(true);
10885 VD->addAttr(NewAttr);
10887 // CUDA E.2.9.4: Within the body of a __device__ or __global__
10888 // function, only __shared__ variables may be declared with
10889 // static storage class.
10890 if (getLangOpts().CUDA && !VD->hasAttr<CUDASharedAttr>() &&
10891 CUDADiagIfDeviceCode(VD->getLocation(),
10892 diag::err_device_static_local_var)
10893 << CurrentCUDATarget())
10894 VD->setInvalidDecl();
10898 // Perform check for initializers of device-side global variables.
10899 // CUDA allows empty constructors as initializers (see E.2.3.1, CUDA
10900 // 7.5). We must also apply the same checks to all __shared__
10901 // variables whether they are local or not. CUDA also allows
10902 // constant initializers for __constant__ and __device__ variables.
10903 if (getLangOpts().CUDA) {
10904 const Expr *Init = VD->getInit();
10905 if (Init && VD->hasGlobalStorage()) {
10906 if (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>() ||
10907 VD->hasAttr<CUDASharedAttr>()) {
10908 assert(!VD->isStaticLocal() || VD->hasAttr<CUDASharedAttr>());
10909 bool AllowedInit = false;
10910 if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(Init))
10912 isEmptyCudaConstructor(VD->getLocation(), CE->getConstructor());
10913 // We'll allow constant initializers even if it's a non-empty
10914 // constructor according to CUDA rules. This deviates from NVCC,
10915 // but allows us to handle things like constexpr constructors.
10916 if (!AllowedInit &&
10917 (VD->hasAttr<CUDADeviceAttr>() || VD->hasAttr<CUDAConstantAttr>()))
10918 AllowedInit = VD->getInit()->isConstantInitializer(
10919 Context, VD->getType()->isReferenceType());
10921 // Also make sure that destructor, if there is one, is empty.
10923 if (CXXRecordDecl *RD = VD->getType()->getAsCXXRecordDecl())
10925 isEmptyCudaDestructor(VD->getLocation(), RD->getDestructor());
10927 if (!AllowedInit) {
10928 Diag(VD->getLocation(), VD->hasAttr<CUDASharedAttr>()
10929 ? diag::err_shared_var_init
10930 : diag::err_dynamic_var_init)
10931 << Init->getSourceRange();
10932 VD->setInvalidDecl();
10935 // This is a host-side global variable. Check that the initializer is
10936 // callable from the host side.
10937 const FunctionDecl *InitFn = nullptr;
10938 if (const CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(Init)) {
10939 InitFn = CE->getConstructor();
10940 } else if (const CallExpr *CE = dyn_cast<CallExpr>(Init)) {
10941 InitFn = CE->getDirectCallee();
10944 CUDAFunctionTarget InitFnTarget = IdentifyCUDATarget(InitFn);
10945 if (InitFnTarget != CFT_Host && InitFnTarget != CFT_HostDevice) {
10946 Diag(VD->getLocation(), diag::err_ref_bad_target_global_initializer)
10947 << InitFnTarget << InitFn;
10948 Diag(InitFn->getLocation(), diag::note_previous_decl) << InitFn;
10949 VD->setInvalidDecl();
10956 // Grab the dllimport or dllexport attribute off of the VarDecl.
10957 const InheritableAttr *DLLAttr = getDLLAttr(VD);
10959 // Imported static data members cannot be defined out-of-line.
10960 if (const auto *IA = dyn_cast_or_null<DLLImportAttr>(DLLAttr)) {
10961 if (VD->isStaticDataMember() && VD->isOutOfLine() &&
10962 VD->isThisDeclarationADefinition()) {
10963 // We allow definitions of dllimport class template static data members
10965 CXXRecordDecl *Context =
10966 cast<CXXRecordDecl>(VD->getFirstDecl()->getDeclContext());
10967 bool IsClassTemplateMember =
10968 isa<ClassTemplatePartialSpecializationDecl>(Context) ||
10969 Context->getDescribedClassTemplate();
10971 Diag(VD->getLocation(),
10972 IsClassTemplateMember
10973 ? diag::warn_attribute_dllimport_static_field_definition
10974 : diag::err_attribute_dllimport_static_field_definition);
10975 Diag(IA->getLocation(), diag::note_attribute);
10976 if (!IsClassTemplateMember)
10977 VD->setInvalidDecl();
10981 // dllimport/dllexport variables cannot be thread local, their TLS index
10982 // isn't exported with the variable.
10983 if (DLLAttr && VD->getTLSKind()) {
10984 auto *F = dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod());
10985 if (F && getDLLAttr(F)) {
10986 assert(VD->isStaticLocal());
10987 // But if this is a static local in a dlimport/dllexport function, the
10988 // function will never be inlined, which means the var would never be
10989 // imported, so having it marked import/export is safe.
10991 Diag(VD->getLocation(), diag::err_attribute_dll_thread_local) << VD
10993 VD->setInvalidDecl();
10997 if (UsedAttr *Attr = VD->getAttr<UsedAttr>()) {
10998 if (!Attr->isInherited() && !VD->isThisDeclarationADefinition()) {
10999 Diag(Attr->getLocation(), diag::warn_attribute_ignored) << Attr;
11000 VD->dropAttr<UsedAttr>();
11004 const DeclContext *DC = VD->getDeclContext();
11005 // If there's a #pragma GCC visibility in scope, and this isn't a class
11006 // member, set the visibility of this variable.
11007 if (DC->getRedeclContext()->isFileContext() && VD->isExternallyVisible())
11008 AddPushedVisibilityAttribute(VD);
11010 // FIXME: Warn on unused templates.
11011 if (VD->isFileVarDecl() && !VD->getDescribedVarTemplate() &&
11012 !isa<VarTemplatePartialSpecializationDecl>(VD))
11013 MarkUnusedFileScopedDecl(VD);
11015 // Now we have parsed the initializer and can update the table of magic
11017 if (!VD->hasAttr<TypeTagForDatatypeAttr>() ||
11018 !VD->getType()->isIntegralOrEnumerationType())
11021 for (const auto *I : ThisDecl->specific_attrs<TypeTagForDatatypeAttr>()) {
11022 const Expr *MagicValueExpr = VD->getInit();
11023 if (!MagicValueExpr) {
11026 llvm::APSInt MagicValueInt;
11027 if (!MagicValueExpr->isIntegerConstantExpr(MagicValueInt, Context)) {
11028 Diag(I->getRange().getBegin(),
11029 diag::err_type_tag_for_datatype_not_ice)
11030 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
11033 if (MagicValueInt.getActiveBits() > 64) {
11034 Diag(I->getRange().getBegin(),
11035 diag::err_type_tag_for_datatype_too_large)
11036 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
11039 uint64_t MagicValue = MagicValueInt.getZExtValue();
11040 RegisterTypeTagForDatatype(I->getArgumentKind(),
11042 I->getMatchingCType(),
11043 I->getLayoutCompatible(),
11044 I->getMustBeNull());
11048 Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
11049 ArrayRef<Decl *> Group) {
11050 SmallVector<Decl*, 8> Decls;
11052 if (DS.isTypeSpecOwned())
11053 Decls.push_back(DS.getRepAsDecl());
11055 DeclaratorDecl *FirstDeclaratorInGroup = nullptr;
11056 DecompositionDecl *FirstDecompDeclaratorInGroup = nullptr;
11057 bool DiagnosedMultipleDecomps = false;
11059 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
11060 if (Decl *D = Group[i]) {
11061 auto *DD = dyn_cast<DeclaratorDecl>(D);
11062 if (DD && !FirstDeclaratorInGroup)
11063 FirstDeclaratorInGroup = DD;
11065 auto *Decomp = dyn_cast<DecompositionDecl>(D);
11066 if (Decomp && !FirstDecompDeclaratorInGroup)
11067 FirstDecompDeclaratorInGroup = Decomp;
11069 // A decomposition declaration cannot be combined with any other
11070 // declaration in the same group.
11071 auto *OtherDD = FirstDeclaratorInGroup;
11072 if (OtherDD == FirstDecompDeclaratorInGroup)
11074 if (OtherDD && FirstDecompDeclaratorInGroup &&
11075 OtherDD != FirstDecompDeclaratorInGroup &&
11076 !DiagnosedMultipleDecomps) {
11077 Diag(FirstDecompDeclaratorInGroup->getLocation(),
11078 diag::err_decomp_decl_not_alone)
11079 << OtherDD->getSourceRange();
11080 DiagnosedMultipleDecomps = true;
11083 Decls.push_back(D);
11087 if (DeclSpec::isDeclRep(DS.getTypeSpecType())) {
11088 if (TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) {
11089 handleTagNumbering(Tag, S);
11090 if (FirstDeclaratorInGroup && !Tag->hasNameForLinkage() &&
11091 getLangOpts().CPlusPlus)
11092 Context.addDeclaratorForUnnamedTagDecl(Tag, FirstDeclaratorInGroup);
11096 return BuildDeclaratorGroup(Decls);
11099 /// BuildDeclaratorGroup - convert a list of declarations into a declaration
11100 /// group, performing any necessary semantic checking.
11101 Sema::DeclGroupPtrTy
11102 Sema::BuildDeclaratorGroup(MutableArrayRef<Decl *> Group) {
11103 // C++14 [dcl.spec.auto]p7: (DR1347)
11104 // If the type that replaces the placeholder type is not the same in each
11105 // deduction, the program is ill-formed.
11106 if (Group.size() > 1) {
11108 CanQualType DeducedCanon;
11109 VarDecl *DeducedDecl = nullptr;
11110 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
11111 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) {
11112 AutoType *AT = D->getType()->getContainedAutoType();
11113 // FIXME: DR1265: if we have a function pointer declaration, we can have
11114 // an 'auto' from a trailing return type. In that case, the return type
11115 // must match the various other uses of 'auto'.
11118 // Don't reissue diagnostics when instantiating a template.
11119 if (D->isInvalidDecl())
11121 QualType U = AT->getDeducedType();
11123 CanQualType UCanon = Context.getCanonicalType(U);
11124 if (Deduced.isNull()) {
11126 DeducedCanon = UCanon;
11128 } else if (DeducedCanon != UCanon) {
11129 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(),
11130 diag::err_auto_different_deductions)
11131 << (unsigned)AT->getKeyword()
11132 << Deduced << DeducedDecl->getDeclName()
11133 << U << D->getDeclName()
11134 << DeducedDecl->getInit()->getSourceRange()
11135 << D->getInit()->getSourceRange();
11136 D->setInvalidDecl();
11144 ActOnDocumentableDecls(Group);
11146 return DeclGroupPtrTy::make(
11147 DeclGroupRef::Create(Context, Group.data(), Group.size()));
11150 void Sema::ActOnDocumentableDecl(Decl *D) {
11151 ActOnDocumentableDecls(D);
11154 void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) {
11155 // Don't parse the comment if Doxygen diagnostics are ignored.
11156 if (Group.empty() || !Group[0])
11159 if (Diags.isIgnored(diag::warn_doc_param_not_found,
11160 Group[0]->getLocation()) &&
11161 Diags.isIgnored(diag::warn_unknown_comment_command_name,
11162 Group[0]->getLocation()))
11165 if (Group.size() >= 2) {
11166 // This is a decl group. Normally it will contain only declarations
11167 // produced from declarator list. But in case we have any definitions or
11168 // additional declaration references:
11169 // 'typedef struct S {} S;'
11170 // 'typedef struct S *S;'
11172 // FinalizeDeclaratorGroup adds these as separate declarations.
11173 Decl *MaybeTagDecl = Group[0];
11174 if (MaybeTagDecl && isa<TagDecl>(MaybeTagDecl)) {
11175 Group = Group.slice(1);
11179 // See if there are any new comments that are not attached to a decl.
11180 ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments();
11181 if (!Comments.empty() &&
11182 !Comments.back()->isAttached()) {
11183 // There is at least one comment that not attached to a decl.
11184 // Maybe it should be attached to one of these decls?
11186 // Note that this way we pick up not only comments that precede the
11187 // declaration, but also comments that *follow* the declaration -- thanks to
11188 // the lookahead in the lexer: we've consumed the semicolon and looked
11189 // ahead through comments.
11190 for (unsigned i = 0, e = Group.size(); i != e; ++i)
11191 Context.getCommentForDecl(Group[i], &PP);
11195 /// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator()
11196 /// to introduce parameters into function prototype scope.
11197 Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) {
11198 const DeclSpec &DS = D.getDeclSpec();
11200 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'.
11202 // C++03 [dcl.stc]p2 also permits 'auto'.
11203 StorageClass SC = SC_None;
11204 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
11206 } else if (getLangOpts().CPlusPlus &&
11207 DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
11209 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) {
11210 Diag(DS.getStorageClassSpecLoc(),
11211 diag::err_invalid_storage_class_in_func_decl);
11212 D.getMutableDeclSpec().ClearStorageClassSpecs();
11215 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
11216 Diag(DS.getThreadStorageClassSpecLoc(), diag::err_invalid_thread)
11217 << DeclSpec::getSpecifierName(TSCS);
11218 if (DS.isInlineSpecified())
11219 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
11220 << getLangOpts().CPlusPlus1z;
11221 if (DS.isConstexprSpecified())
11222 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr)
11224 if (DS.isConceptSpecified())
11225 Diag(DS.getConceptSpecLoc(), diag::err_concept_wrong_decl_kind);
11227 DiagnoseFunctionSpecifiers(DS);
11229 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
11230 QualType parmDeclType = TInfo->getType();
11232 if (getLangOpts().CPlusPlus) {
11233 // Check that there are no default arguments inside the type of this
11235 CheckExtraCXXDefaultArguments(D);
11237 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
11238 if (D.getCXXScopeSpec().isSet()) {
11239 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator)
11240 << D.getCXXScopeSpec().getRange();
11241 D.getCXXScopeSpec().clear();
11245 // Ensure we have a valid name
11246 IdentifierInfo *II = nullptr;
11248 II = D.getIdentifier();
11250 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name)
11251 << GetNameForDeclarator(D).getName();
11252 D.setInvalidType(true);
11256 // Check for redeclaration of parameters, e.g. int foo(int x, int x);
11258 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName,
11261 if (R.isSingleResult()) {
11262 NamedDecl *PrevDecl = R.getFoundDecl();
11263 if (PrevDecl->isTemplateParameter()) {
11264 // Maybe we will complain about the shadowed template parameter.
11265 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
11266 // Just pretend that we didn't see the previous declaration.
11267 PrevDecl = nullptr;
11268 } else if (S->isDeclScope(PrevDecl)) {
11269 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II;
11270 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
11272 // Recover by removing the name
11274 D.SetIdentifier(nullptr, D.getIdentifierLoc());
11275 D.setInvalidType(true);
11280 // Temporarily put parameter variables in the translation unit, not
11281 // the enclosing context. This prevents them from accidentally
11282 // looking like class members in C++.
11283 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(),
11285 D.getIdentifierLoc(), II,
11286 parmDeclType, TInfo,
11289 if (D.isInvalidType())
11290 New->setInvalidDecl();
11292 assert(S->isFunctionPrototypeScope());
11293 assert(S->getFunctionPrototypeDepth() >= 1);
11294 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1,
11295 S->getNextFunctionPrototypeIndex());
11297 // Add the parameter declaration into this scope.
11300 IdResolver.AddDecl(New);
11302 ProcessDeclAttributes(S, New, D);
11304 if (D.getDeclSpec().isModulePrivateSpecified())
11305 Diag(New->getLocation(), diag::err_module_private_local)
11306 << 1 << New->getDeclName()
11307 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
11308 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
11310 if (New->hasAttr<BlocksAttr>()) {
11311 Diag(New->getLocation(), diag::err_block_on_nonlocal);
11316 /// \brief Synthesizes a variable for a parameter arising from a
11318 ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC,
11319 SourceLocation Loc,
11321 /* FIXME: setting StartLoc == Loc.
11322 Would it be worth to modify callers so as to provide proper source
11323 location for the unnamed parameters, embedding the parameter's type? */
11324 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, nullptr,
11325 T, Context.getTrivialTypeSourceInfo(T, Loc),
11327 Param->setImplicit();
11331 void Sema::DiagnoseUnusedParameters(ArrayRef<ParmVarDecl *> Parameters) {
11332 // Don't diagnose unused-parameter errors in template instantiations; we
11333 // will already have done so in the template itself.
11334 if (!ActiveTemplateInstantiations.empty())
11337 for (const ParmVarDecl *Parameter : Parameters) {
11338 if (!Parameter->isReferenced() && Parameter->getDeclName() &&
11339 !Parameter->hasAttr<UnusedAttr>()) {
11340 Diag(Parameter->getLocation(), diag::warn_unused_parameter)
11341 << Parameter->getDeclName();
11346 void Sema::DiagnoseSizeOfParametersAndReturnValue(
11347 ArrayRef<ParmVarDecl *> Parameters, QualType ReturnTy, NamedDecl *D) {
11348 if (LangOpts.NumLargeByValueCopy == 0) // No check.
11351 // Warn if the return value is pass-by-value and larger than the specified
11353 if (!ReturnTy->isDependentType() && ReturnTy.isPODType(Context)) {
11354 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity();
11355 if (Size > LangOpts.NumLargeByValueCopy)
11356 Diag(D->getLocation(), diag::warn_return_value_size)
11357 << D->getDeclName() << Size;
11360 // Warn if any parameter is pass-by-value and larger than the specified
11362 for (const ParmVarDecl *Parameter : Parameters) {
11363 QualType T = Parameter->getType();
11364 if (T->isDependentType() || !T.isPODType(Context))
11366 unsigned Size = Context.getTypeSizeInChars(T).getQuantity();
11367 if (Size > LangOpts.NumLargeByValueCopy)
11368 Diag(Parameter->getLocation(), diag::warn_parameter_size)
11369 << Parameter->getDeclName() << Size;
11373 ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc,
11374 SourceLocation NameLoc, IdentifierInfo *Name,
11375 QualType T, TypeSourceInfo *TSInfo,
11377 // In ARC, infer a lifetime qualifier for appropriate parameter types.
11378 if (getLangOpts().ObjCAutoRefCount &&
11379 T.getObjCLifetime() == Qualifiers::OCL_None &&
11380 T->isObjCLifetimeType()) {
11382 Qualifiers::ObjCLifetime lifetime;
11384 // Special cases for arrays:
11385 // - if it's const, use __unsafe_unretained
11386 // - otherwise, it's an error
11387 if (T->isArrayType()) {
11388 if (!T.isConstQualified()) {
11389 DelayedDiagnostics.add(
11390 sema::DelayedDiagnostic::makeForbiddenType(
11391 NameLoc, diag::err_arc_array_param_no_ownership, T, false));
11393 lifetime = Qualifiers::OCL_ExplicitNone;
11395 lifetime = T->getObjCARCImplicitLifetime();
11397 T = Context.getLifetimeQualifiedType(T, lifetime);
11400 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name,
11401 Context.getAdjustedParameterType(T),
11402 TSInfo, SC, nullptr);
11404 // Parameters can not be abstract class types.
11405 // For record types, this is done by the AbstractClassUsageDiagnoser once
11406 // the class has been completely parsed.
11407 if (!CurContext->isRecord() &&
11408 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl,
11409 AbstractParamType))
11410 New->setInvalidDecl();
11412 // Parameter declarators cannot be interface types. All ObjC objects are
11413 // passed by reference.
11414 if (T->isObjCObjectType()) {
11415 SourceLocation TypeEndLoc =
11416 getLocForEndOfToken(TSInfo->getTypeLoc().getLocEnd());
11418 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T
11419 << FixItHint::CreateInsertion(TypeEndLoc, "*");
11420 T = Context.getObjCObjectPointerType(T);
11424 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
11425 // duration shall not be qualified by an address-space qualifier."
11426 // Since all parameters have automatic store duration, they can not have
11427 // an address space.
11428 if (T.getAddressSpace() != 0) {
11429 // OpenCL allows function arguments declared to be an array of a type
11430 // to be qualified with an address space.
11431 if (!(getLangOpts().OpenCL && T->isArrayType())) {
11432 Diag(NameLoc, diag::err_arg_with_address_space);
11433 New->setInvalidDecl();
11440 void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
11441 SourceLocation LocAfterDecls) {
11442 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
11444 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared'
11445 // for a K&R function.
11446 if (!FTI.hasPrototype) {
11447 for (int i = FTI.NumParams; i != 0; /* decrement in loop */) {
11449 if (FTI.Params[i].Param == nullptr) {
11450 SmallString<256> Code;
11451 llvm::raw_svector_ostream(Code)
11452 << " int " << FTI.Params[i].Ident->getName() << ";\n";
11453 Diag(FTI.Params[i].IdentLoc, diag::ext_param_not_declared)
11454 << FTI.Params[i].Ident
11455 << FixItHint::CreateInsertion(LocAfterDecls, Code);
11457 // Implicitly declare the argument as type 'int' for lack of a better
11459 AttributeFactory attrs;
11460 DeclSpec DS(attrs);
11461 const char* PrevSpec; // unused
11462 unsigned DiagID; // unused
11463 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.Params[i].IdentLoc, PrevSpec,
11464 DiagID, Context.getPrintingPolicy());
11465 // Use the identifier location for the type source range.
11466 DS.SetRangeStart(FTI.Params[i].IdentLoc);
11467 DS.SetRangeEnd(FTI.Params[i].IdentLoc);
11468 Declarator ParamD(DS, Declarator::KNRTypeListContext);
11469 ParamD.SetIdentifier(FTI.Params[i].Ident, FTI.Params[i].IdentLoc);
11470 FTI.Params[i].Param = ActOnParamDeclarator(S, ParamD);
11477 Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D,
11478 MultiTemplateParamsArg TemplateParameterLists,
11479 SkipBodyInfo *SkipBody) {
11480 assert(getCurFunctionDecl() == nullptr && "Function parsing confused");
11481 assert(D.isFunctionDeclarator() && "Not a function declarator!");
11482 Scope *ParentScope = FnBodyScope->getParent();
11484 D.setFunctionDefinitionKind(FDK_Definition);
11485 Decl *DP = HandleDeclarator(ParentScope, D, TemplateParameterLists);
11486 return ActOnStartOfFunctionDef(FnBodyScope, DP, SkipBody);
11489 void Sema::ActOnFinishInlineFunctionDef(FunctionDecl *D) {
11490 Consumer.HandleInlineFunctionDefinition(D);
11493 static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD,
11494 const FunctionDecl*& PossibleZeroParamPrototype) {
11495 // Don't warn about invalid declarations.
11496 if (FD->isInvalidDecl())
11499 // Or declarations that aren't global.
11500 if (!FD->isGlobal())
11503 // Don't warn about C++ member functions.
11504 if (isa<CXXMethodDecl>(FD))
11507 // Don't warn about 'main'.
11511 // Don't warn about inline functions.
11512 if (FD->isInlined())
11515 // Don't warn about function templates.
11516 if (FD->getDescribedFunctionTemplate())
11519 // Don't warn about function template specializations.
11520 if (FD->isFunctionTemplateSpecialization())
11523 // Don't warn for OpenCL kernels.
11524 if (FD->hasAttr<OpenCLKernelAttr>())
11527 // Don't warn on explicitly deleted functions.
11528 if (FD->isDeleted())
11531 bool MissingPrototype = true;
11532 for (const FunctionDecl *Prev = FD->getPreviousDecl();
11533 Prev; Prev = Prev->getPreviousDecl()) {
11534 // Ignore any declarations that occur in function or method
11535 // scope, because they aren't visible from the header.
11536 if (Prev->getLexicalDeclContext()->isFunctionOrMethod())
11539 MissingPrototype = !Prev->getType()->isFunctionProtoType();
11540 if (FD->getNumParams() == 0)
11541 PossibleZeroParamPrototype = Prev;
11545 return MissingPrototype;
11549 Sema::CheckForFunctionRedefinition(FunctionDecl *FD,
11550 const FunctionDecl *EffectiveDefinition,
11551 SkipBodyInfo *SkipBody) {
11552 // Don't complain if we're in GNU89 mode and the previous definition
11553 // was an extern inline function.
11554 const FunctionDecl *Definition = EffectiveDefinition;
11556 if (!FD->isDefined(Definition))
11559 if (canRedefineFunction(Definition, getLangOpts()))
11562 // If we don't have a visible definition of the function, and it's inline or
11563 // a template, skip the new definition.
11564 if (SkipBody && !hasVisibleDefinition(Definition) &&
11565 (Definition->getFormalLinkage() == InternalLinkage ||
11566 Definition->isInlined() ||
11567 Definition->getDescribedFunctionTemplate() ||
11568 Definition->getNumTemplateParameterLists())) {
11569 SkipBody->ShouldSkip = true;
11570 if (auto *TD = Definition->getDescribedFunctionTemplate())
11571 makeMergedDefinitionVisible(TD, FD->getLocation());
11572 makeMergedDefinitionVisible(const_cast<FunctionDecl*>(Definition),
11573 FD->getLocation());
11577 if (getLangOpts().GNUMode && Definition->isInlineSpecified() &&
11578 Definition->getStorageClass() == SC_Extern)
11579 Diag(FD->getLocation(), diag::err_redefinition_extern_inline)
11580 << FD->getDeclName() << getLangOpts().CPlusPlus;
11582 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName();
11584 Diag(Definition->getLocation(), diag::note_previous_definition);
11585 FD->setInvalidDecl();
11588 static void RebuildLambdaScopeInfo(CXXMethodDecl *CallOperator,
11590 CXXRecordDecl *const LambdaClass = CallOperator->getParent();
11592 LambdaScopeInfo *LSI = S.PushLambdaScope();
11593 LSI->CallOperator = CallOperator;
11594 LSI->Lambda = LambdaClass;
11595 LSI->ReturnType = CallOperator->getReturnType();
11596 const LambdaCaptureDefault LCD = LambdaClass->getLambdaCaptureDefault();
11598 if (LCD == LCD_None)
11599 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_None;
11600 else if (LCD == LCD_ByCopy)
11601 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByval;
11602 else if (LCD == LCD_ByRef)
11603 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByref;
11604 DeclarationNameInfo DNI = CallOperator->getNameInfo();
11606 LSI->IntroducerRange = DNI.getCXXOperatorNameRange();
11607 LSI->Mutable = !CallOperator->isConst();
11609 // Add the captures to the LSI so they can be noted as already
11610 // captured within tryCaptureVar.
11611 auto I = LambdaClass->field_begin();
11612 for (const auto &C : LambdaClass->captures()) {
11613 if (C.capturesVariable()) {
11614 VarDecl *VD = C.getCapturedVar();
11615 if (VD->isInitCapture())
11616 S.CurrentInstantiationScope->InstantiatedLocal(VD, VD);
11617 QualType CaptureType = VD->getType();
11618 const bool ByRef = C.getCaptureKind() == LCK_ByRef;
11619 LSI->addCapture(VD, /*IsBlock*/false, ByRef,
11620 /*RefersToEnclosingVariableOrCapture*/true, C.getLocation(),
11621 /*EllipsisLoc*/C.isPackExpansion()
11622 ? C.getEllipsisLoc() : SourceLocation(),
11623 CaptureType, /*Expr*/ nullptr);
11625 } else if (C.capturesThis()) {
11626 LSI->addThisCapture(/*Nested*/ false, C.getLocation(),
11628 C.getCaptureKind() == LCK_StarThis);
11630 LSI->addVLATypeCapture(C.getLocation(), I->getType());
11636 Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D,
11637 SkipBodyInfo *SkipBody) {
11638 // Clear the last template instantiation error context.
11639 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation();
11643 FunctionDecl *FD = nullptr;
11645 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D))
11646 FD = FunTmpl->getTemplatedDecl();
11648 FD = cast<FunctionDecl>(D);
11650 // See if this is a redefinition.
11651 if (!FD->isLateTemplateParsed()) {
11652 CheckForFunctionRedefinition(FD, nullptr, SkipBody);
11654 // If we're skipping the body, we're done. Don't enter the scope.
11655 if (SkipBody && SkipBody->ShouldSkip)
11659 // Mark this function as "will have a body eventually". This lets users to
11660 // call e.g. isInlineDefinitionExternallyVisible while we're still parsing
11662 FD->setWillHaveBody();
11664 // If we are instantiating a generic lambda call operator, push
11665 // a LambdaScopeInfo onto the function stack. But use the information
11666 // that's already been calculated (ActOnLambdaExpr) to prime the current
11667 // LambdaScopeInfo.
11668 // When the template operator is being specialized, the LambdaScopeInfo,
11669 // has to be properly restored so that tryCaptureVariable doesn't try
11670 // and capture any new variables. In addition when calculating potential
11671 // captures during transformation of nested lambdas, it is necessary to
11672 // have the LSI properly restored.
11673 if (isGenericLambdaCallOperatorSpecialization(FD)) {
11674 assert(ActiveTemplateInstantiations.size() &&
11675 "There should be an active template instantiation on the stack "
11676 "when instantiating a generic lambda!");
11677 RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this);
11680 // Enter a new function scope
11681 PushFunctionScope();
11683 // Builtin functions cannot be defined.
11684 if (unsigned BuiltinID = FD->getBuiltinID()) {
11685 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) &&
11686 !Context.BuiltinInfo.isPredefinedRuntimeFunction(BuiltinID)) {
11687 Diag(FD->getLocation(), diag::err_builtin_definition) << FD;
11688 FD->setInvalidDecl();
11692 // The return type of a function definition must be complete
11693 // (C99 6.9.1p3, C++ [dcl.fct]p6).
11694 QualType ResultType = FD->getReturnType();
11695 if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
11696 !FD->isInvalidDecl() &&
11697 RequireCompleteType(FD->getLocation(), ResultType,
11698 diag::err_func_def_incomplete_result))
11699 FD->setInvalidDecl();
11702 PushDeclContext(FnBodyScope, FD);
11704 // Check the validity of our function parameters
11705 CheckParmsForFunctionDef(FD->parameters(),
11706 /*CheckParameterNames=*/true);
11708 // Add non-parameter declarations already in the function to the current
11711 for (Decl *NPD : FD->decls()) {
11712 auto *NonParmDecl = dyn_cast<NamedDecl>(NPD);
11715 assert(!isa<ParmVarDecl>(NonParmDecl) &&
11716 "parameters should not be in newly created FD yet");
11718 // If the decl has a name, make it accessible in the current scope.
11719 if (NonParmDecl->getDeclName())
11720 PushOnScopeChains(NonParmDecl, FnBodyScope, /*AddToContext=*/false);
11722 // Similarly, dive into enums and fish their constants out, making them
11723 // accessible in this scope.
11724 if (auto *ED = dyn_cast<EnumDecl>(NonParmDecl)) {
11725 for (auto *EI : ED->enumerators())
11726 PushOnScopeChains(EI, FnBodyScope, /*AddToContext=*/false);
11731 // Introduce our parameters into the function scope
11732 for (auto Param : FD->parameters()) {
11733 Param->setOwningFunction(FD);
11735 // If this has an identifier, add it to the scope stack.
11736 if (Param->getIdentifier() && FnBodyScope) {
11737 CheckShadow(FnBodyScope, Param);
11739 PushOnScopeChains(Param, FnBodyScope);
11743 // Ensure that the function's exception specification is instantiated.
11744 if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>())
11745 ResolveExceptionSpec(D->getLocation(), FPT);
11747 // dllimport cannot be applied to non-inline function definitions.
11748 if (FD->hasAttr<DLLImportAttr>() && !FD->isInlined() &&
11749 !FD->isTemplateInstantiation()) {
11750 assert(!FD->hasAttr<DLLExportAttr>());
11751 Diag(FD->getLocation(), diag::err_attribute_dllimport_function_definition);
11752 FD->setInvalidDecl();
11755 // We want to attach documentation to original Decl (which might be
11756 // a function template).
11757 ActOnDocumentableDecl(D);
11758 if (getCurLexicalContext()->isObjCContainer() &&
11759 getCurLexicalContext()->getDeclKind() != Decl::ObjCCategoryImpl &&
11760 getCurLexicalContext()->getDeclKind() != Decl::ObjCImplementation)
11761 Diag(FD->getLocation(), diag::warn_function_def_in_objc_container);
11766 /// \brief Given the set of return statements within a function body,
11767 /// compute the variables that are subject to the named return value
11770 /// Each of the variables that is subject to the named return value
11771 /// optimization will be marked as NRVO variables in the AST, and any
11772 /// return statement that has a marked NRVO variable as its NRVO candidate can
11773 /// use the named return value optimization.
11775 /// This function applies a very simplistic algorithm for NRVO: if every return
11776 /// statement in the scope of a variable has the same NRVO candidate, that
11777 /// candidate is an NRVO variable.
11778 void Sema::computeNRVO(Stmt *Body, FunctionScopeInfo *Scope) {
11779 ReturnStmt **Returns = Scope->Returns.data();
11781 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) {
11782 if (const VarDecl *NRVOCandidate = Returns[I]->getNRVOCandidate()) {
11783 if (!NRVOCandidate->isNRVOVariable())
11784 Returns[I]->setNRVOCandidate(nullptr);
11789 bool Sema::canDelayFunctionBody(const Declarator &D) {
11790 // We can't delay parsing the body of a constexpr function template (yet).
11791 if (D.getDeclSpec().isConstexprSpecified())
11794 // We can't delay parsing the body of a function template with a deduced
11795 // return type (yet).
11796 if (D.getDeclSpec().containsPlaceholderType()) {
11797 // If the placeholder introduces a non-deduced trailing return type,
11798 // we can still delay parsing it.
11799 if (D.getNumTypeObjects()) {
11800 const auto &Outer = D.getTypeObject(D.getNumTypeObjects() - 1);
11801 if (Outer.Kind == DeclaratorChunk::Function &&
11802 Outer.Fun.hasTrailingReturnType()) {
11803 QualType Ty = GetTypeFromParser(Outer.Fun.getTrailingReturnType());
11804 return Ty.isNull() || !Ty->isUndeducedType();
11813 bool Sema::canSkipFunctionBody(Decl *D) {
11814 // We cannot skip the body of a function (or function template) which is
11815 // constexpr, since we may need to evaluate its body in order to parse the
11816 // rest of the file.
11817 // We cannot skip the body of a function with an undeduced return type,
11818 // because any callers of that function need to know the type.
11819 if (const FunctionDecl *FD = D->getAsFunction())
11820 if (FD->isConstexpr() || FD->getReturnType()->isUndeducedType())
11822 return Consumer.shouldSkipFunctionBody(D);
11825 Decl *Sema::ActOnSkippedFunctionBody(Decl *Decl) {
11826 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Decl))
11827 FD->setHasSkippedBody();
11828 else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(Decl))
11829 MD->setHasSkippedBody();
11833 Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) {
11834 return ActOnFinishFunctionBody(D, BodyArg, false);
11837 Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
11838 bool IsInstantiation) {
11839 FunctionDecl *FD = dcl ? dcl->getAsFunction() : nullptr;
11841 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
11842 sema::AnalysisBasedWarnings::Policy *ActivePolicy = nullptr;
11844 if (getLangOpts().CoroutinesTS && !getCurFunction()->CoroutineStmts.empty())
11845 CheckCompletedCoroutineBody(FD, Body);
11850 if (getLangOpts().CPlusPlus14) {
11851 if (!FD->isInvalidDecl() && Body && !FD->isDependentContext() &&
11852 FD->getReturnType()->isUndeducedType()) {
11853 // If the function has a deduced result type but contains no 'return'
11854 // statements, the result type as written must be exactly 'auto', and
11855 // the deduced result type is 'void'.
11856 if (!FD->getReturnType()->getAs<AutoType>()) {
11857 Diag(dcl->getLocation(), diag::err_auto_fn_no_return_but_not_auto)
11858 << FD->getReturnType();
11859 FD->setInvalidDecl();
11861 // Substitute 'void' for the 'auto' in the type.
11862 TypeLoc ResultType = getReturnTypeLoc(FD);
11863 Context.adjustDeducedFunctionResultType(
11864 FD, SubstAutoType(ResultType.getType(), Context.VoidTy));
11867 } else if (getLangOpts().CPlusPlus11 && isLambdaCallOperator(FD)) {
11868 // In C++11, we don't use 'auto' deduction rules for lambda call
11869 // operators because we don't support return type deduction.
11870 auto *LSI = getCurLambda();
11871 if (LSI->HasImplicitReturnType) {
11872 deduceClosureReturnType(*LSI);
11874 // C++11 [expr.prim.lambda]p4:
11875 // [...] if there are no return statements in the compound-statement
11876 // [the deduced type is] the type void
11878 LSI->ReturnType.isNull() ? Context.VoidTy : LSI->ReturnType;
11880 // Update the return type to the deduced type.
11881 const FunctionProtoType *Proto =
11882 FD->getType()->getAs<FunctionProtoType>();
11883 FD->setType(Context.getFunctionType(RetType, Proto->getParamTypes(),
11884 Proto->getExtProtoInfo()));
11888 // The only way to be included in UndefinedButUsed is if there is an
11889 // ODR use before the definition. Avoid the expensive map lookup if this
11890 // is the first declaration.
11891 if (!FD->isFirstDecl() && FD->getPreviousDecl()->isUsed()) {
11892 if (!FD->isExternallyVisible())
11893 UndefinedButUsed.erase(FD);
11894 else if (FD->isInlined() &&
11895 !LangOpts.GNUInline &&
11896 (!FD->getPreviousDecl()->hasAttr<GNUInlineAttr>()))
11897 UndefinedButUsed.erase(FD);
11900 // If the function implicitly returns zero (like 'main') or is naked,
11901 // don't complain about missing return statements.
11902 if (FD->hasImplicitReturnZero() || FD->hasAttr<NakedAttr>())
11903 WP.disableCheckFallThrough();
11905 // MSVC permits the use of pure specifier (=0) on function definition,
11906 // defined at class scope, warn about this non-standard construct.
11907 if (getLangOpts().MicrosoftExt && FD->isPure() && FD->isCanonicalDecl())
11908 Diag(FD->getLocation(), diag::ext_pure_function_definition);
11910 if (!FD->isInvalidDecl()) {
11911 // Don't diagnose unused parameters of defaulted or deleted functions.
11912 if (!FD->isDeleted() && !FD->isDefaulted())
11913 DiagnoseUnusedParameters(FD->parameters());
11914 DiagnoseSizeOfParametersAndReturnValue(FD->parameters(),
11915 FD->getReturnType(), FD);
11917 // If this is a structor, we need a vtable.
11918 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD))
11919 MarkVTableUsed(FD->getLocation(), Constructor->getParent());
11920 else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(FD))
11921 MarkVTableUsed(FD->getLocation(), Destructor->getParent());
11923 // Try to apply the named return value optimization. We have to check
11924 // if we can do this here because lambdas keep return statements around
11925 // to deduce an implicit return type.
11926 if (getLangOpts().CPlusPlus && FD->getReturnType()->isRecordType() &&
11927 !FD->isDependentContext())
11928 computeNRVO(Body, getCurFunction());
11931 // GNU warning -Wmissing-prototypes:
11932 // Warn if a global function is defined without a previous
11933 // prototype declaration. This warning is issued even if the
11934 // definition itself provides a prototype. The aim is to detect
11935 // global functions that fail to be declared in header files.
11936 const FunctionDecl *PossibleZeroParamPrototype = nullptr;
11937 if (ShouldWarnAboutMissingPrototype(FD, PossibleZeroParamPrototype)) {
11938 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD;
11940 if (PossibleZeroParamPrototype) {
11941 // We found a declaration that is not a prototype,
11942 // but that could be a zero-parameter prototype
11943 if (TypeSourceInfo *TI =
11944 PossibleZeroParamPrototype->getTypeSourceInfo()) {
11945 TypeLoc TL = TI->getTypeLoc();
11946 if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>())
11947 Diag(PossibleZeroParamPrototype->getLocation(),
11948 diag::note_declaration_not_a_prototype)
11949 << PossibleZeroParamPrototype
11950 << FixItHint::CreateInsertion(FTL.getRParenLoc(), "void");
11954 // GNU warning -Wstrict-prototypes
11955 // Warn if K&R function is defined without a previous declaration.
11956 // This warning is issued only if the definition itself does not provide
11957 // a prototype. Only K&R definitions do not provide a prototype.
11958 // An empty list in a function declarator that is part of a definition
11959 // of that function specifies that the function has no parameters
11960 // (C99 6.7.5.3p14)
11961 if (!FD->hasWrittenPrototype() && FD->getNumParams() > 0 &&
11962 !LangOpts.CPlusPlus) {
11963 TypeSourceInfo *TI = FD->getTypeSourceInfo();
11964 TypeLoc TL = TI->getTypeLoc();
11965 FunctionTypeLoc FTL = TL.castAs<FunctionTypeLoc>();
11966 Diag(FTL.getLParenLoc(), diag::warn_strict_prototypes) << 1;
11970 if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) {
11971 const CXXMethodDecl *KeyFunction;
11972 if (MD->isOutOfLine() && (MD = MD->getCanonicalDecl()) &&
11974 (KeyFunction = Context.getCurrentKeyFunction(MD->getParent())) &&
11975 MD == KeyFunction->getCanonicalDecl()) {
11976 // Update the key-function state if necessary for this ABI.
11977 if (FD->isInlined() &&
11978 !Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
11979 Context.setNonKeyFunction(MD);
11981 // If the newly-chosen key function is already defined, then we
11982 // need to mark the vtable as used retroactively.
11983 KeyFunction = Context.getCurrentKeyFunction(MD->getParent());
11984 const FunctionDecl *Definition;
11985 if (KeyFunction && KeyFunction->isDefined(Definition))
11986 MarkVTableUsed(Definition->getLocation(), MD->getParent(), true);
11988 // We just defined they key function; mark the vtable as used.
11989 MarkVTableUsed(FD->getLocation(), MD->getParent(), true);
11994 assert((FD == getCurFunctionDecl() || getCurLambda()->CallOperator == FD) &&
11995 "Function parsing confused");
11996 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) {
11997 assert(MD == getCurMethodDecl() && "Method parsing confused");
11999 if (!MD->isInvalidDecl()) {
12000 DiagnoseUnusedParameters(MD->parameters());
12001 DiagnoseSizeOfParametersAndReturnValue(MD->parameters(),
12002 MD->getReturnType(), MD);
12005 computeNRVO(Body, getCurFunction());
12007 if (getCurFunction()->ObjCShouldCallSuper) {
12008 Diag(MD->getLocEnd(), diag::warn_objc_missing_super_call)
12009 << MD->getSelector().getAsString();
12010 getCurFunction()->ObjCShouldCallSuper = false;
12012 if (getCurFunction()->ObjCWarnForNoDesignatedInitChain) {
12013 const ObjCMethodDecl *InitMethod = nullptr;
12014 bool isDesignated =
12015 MD->isDesignatedInitializerForTheInterface(&InitMethod);
12016 assert(isDesignated && InitMethod);
12017 (void)isDesignated;
12019 auto superIsNSObject = [&](const ObjCMethodDecl *MD) {
12020 auto IFace = MD->getClassInterface();
12023 auto SuperD = IFace->getSuperClass();
12026 return SuperD->getIdentifier() ==
12027 NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject);
12029 // Don't issue this warning for unavailable inits or direct subclasses
12031 if (!MD->isUnavailable() && !superIsNSObject(MD)) {
12032 Diag(MD->getLocation(),
12033 diag::warn_objc_designated_init_missing_super_call);
12034 Diag(InitMethod->getLocation(),
12035 diag::note_objc_designated_init_marked_here);
12037 getCurFunction()->ObjCWarnForNoDesignatedInitChain = false;
12039 if (getCurFunction()->ObjCWarnForNoInitDelegation) {
12040 // Don't issue this warning for unavaialable inits.
12041 if (!MD->isUnavailable())
12042 Diag(MD->getLocation(),
12043 diag::warn_objc_secondary_init_missing_init_call);
12044 getCurFunction()->ObjCWarnForNoInitDelegation = false;
12050 if (Body && getCurFunction()->HasPotentialAvailabilityViolations)
12051 DiagnoseUnguardedAvailabilityViolations(dcl);
12053 assert(!getCurFunction()->ObjCShouldCallSuper &&
12054 "This should only be set for ObjC methods, which should have been "
12055 "handled in the block above.");
12057 // Verify and clean out per-function state.
12058 if (Body && (!FD || !FD->isDefaulted())) {
12059 // C++ constructors that have function-try-blocks can't have return
12060 // statements in the handlers of that block. (C++ [except.handle]p14)
12062 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body))
12063 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body));
12065 // Verify that gotos and switch cases don't jump into scopes illegally.
12066 if (getCurFunction()->NeedsScopeChecking() &&
12067 !PP.isCodeCompletionEnabled())
12068 DiagnoseInvalidJumps(Body);
12070 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) {
12071 if (!Destructor->getParent()->isDependentType())
12072 CheckDestructor(Destructor);
12074 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
12075 Destructor->getParent());
12078 // If any errors have occurred, clear out any temporaries that may have
12079 // been leftover. This ensures that these temporaries won't be picked up for
12080 // deletion in some later function.
12081 if (getDiagnostics().hasErrorOccurred() ||
12082 getDiagnostics().getSuppressAllDiagnostics()) {
12083 DiscardCleanupsInEvaluationContext();
12085 if (!getDiagnostics().hasUncompilableErrorOccurred() &&
12086 !isa<FunctionTemplateDecl>(dcl)) {
12087 // Since the body is valid, issue any analysis-based warnings that are
12089 ActivePolicy = &WP;
12092 if (!IsInstantiation && FD && FD->isConstexpr() && !FD->isInvalidDecl() &&
12093 (!CheckConstexprFunctionDecl(FD) ||
12094 !CheckConstexprFunctionBody(FD, Body)))
12095 FD->setInvalidDecl();
12097 if (FD && FD->hasAttr<NakedAttr>()) {
12098 for (const Stmt *S : Body->children()) {
12099 // Allow local register variables without initializer as they don't
12100 // require prologue.
12101 bool RegisterVariables = false;
12102 if (auto *DS = dyn_cast<DeclStmt>(S)) {
12103 for (const auto *Decl : DS->decls()) {
12104 if (const auto *Var = dyn_cast<VarDecl>(Decl)) {
12105 RegisterVariables =
12106 Var->hasAttr<AsmLabelAttr>() && !Var->hasInit();
12107 if (!RegisterVariables)
12112 if (RegisterVariables)
12114 if (!isa<AsmStmt>(S) && !isa<NullStmt>(S)) {
12115 Diag(S->getLocStart(), diag::err_non_asm_stmt_in_naked_function);
12116 Diag(FD->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
12117 FD->setInvalidDecl();
12123 assert(ExprCleanupObjects.size() ==
12124 ExprEvalContexts.back().NumCleanupObjects &&
12125 "Leftover temporaries in function");
12126 assert(!Cleanup.exprNeedsCleanups() && "Unaccounted cleanups in function");
12127 assert(MaybeODRUseExprs.empty() &&
12128 "Leftover expressions for odr-use checking");
12131 if (!IsInstantiation)
12134 PopFunctionScopeInfo(ActivePolicy, dcl);
12135 // If any errors have occurred, clear out any temporaries that may have
12136 // been leftover. This ensures that these temporaries won't be picked up for
12137 // deletion in some later function.
12138 if (getDiagnostics().hasErrorOccurred()) {
12139 DiscardCleanupsInEvaluationContext();
12145 /// When we finish delayed parsing of an attribute, we must attach it to the
12147 void Sema::ActOnFinishDelayedAttribute(Scope *S, Decl *D,
12148 ParsedAttributes &Attrs) {
12149 // Always attach attributes to the underlying decl.
12150 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
12151 D = TD->getTemplatedDecl();
12152 ProcessDeclAttributeList(S, D, Attrs.getList());
12154 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(D))
12155 if (Method->isStatic())
12156 checkThisInStaticMemberFunctionAttributes(Method);
12159 /// ImplicitlyDefineFunction - An undeclared identifier was used in a function
12160 /// call, forming a call to an implicitly defined function (per C99 6.5.1p2).
12161 NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
12162 IdentifierInfo &II, Scope *S) {
12163 // Before we produce a declaration for an implicitly defined
12164 // function, see whether there was a locally-scoped declaration of
12165 // this name as a function or variable. If so, use that
12166 // (non-visible) declaration, and complain about it.
12167 if (NamedDecl *ExternCPrev = findLocallyScopedExternCDecl(&II)) {
12168 Diag(Loc, diag::warn_use_out_of_scope_declaration) << ExternCPrev;
12169 Diag(ExternCPrev->getLocation(), diag::note_previous_declaration);
12170 return ExternCPrev;
12173 // Extension in C99. Legal in C90, but warn about it.
12175 if (II.getName().startswith("__builtin_"))
12176 diag_id = diag::warn_builtin_unknown;
12177 else if (getLangOpts().C99)
12178 diag_id = diag::ext_implicit_function_decl;
12180 diag_id = diag::warn_implicit_function_decl;
12181 Diag(Loc, diag_id) << &II;
12183 // Because typo correction is expensive, only do it if the implicit
12184 // function declaration is going to be treated as an error.
12185 if (Diags.getDiagnosticLevel(diag_id, Loc) >= DiagnosticsEngine::Error) {
12186 TypoCorrection Corrected;
12188 (Corrected = CorrectTypo(
12189 DeclarationNameInfo(&II, Loc), LookupOrdinaryName, S, nullptr,
12190 llvm::make_unique<DeclFilterCCC<FunctionDecl>>(), CTK_NonError)))
12191 diagnoseTypo(Corrected, PDiag(diag::note_function_suggestion),
12192 /*ErrorRecovery*/false);
12195 // Set a Declarator for the implicit definition: int foo();
12197 AttributeFactory attrFactory;
12198 DeclSpec DS(attrFactory);
12200 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID,
12201 Context.getPrintingPolicy());
12202 (void)Error; // Silence warning.
12203 assert(!Error && "Error setting up implicit decl!");
12204 SourceLocation NoLoc;
12205 Declarator D(DS, Declarator::BlockContext);
12206 D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false,
12207 /*IsAmbiguous=*/false,
12208 /*LParenLoc=*/NoLoc,
12209 /*Params=*/nullptr,
12211 /*EllipsisLoc=*/NoLoc,
12212 /*RParenLoc=*/NoLoc,
12214 /*RefQualifierIsLvalueRef=*/true,
12215 /*RefQualifierLoc=*/NoLoc,
12216 /*ConstQualifierLoc=*/NoLoc,
12217 /*VolatileQualifierLoc=*/NoLoc,
12218 /*RestrictQualifierLoc=*/NoLoc,
12219 /*MutableLoc=*/NoLoc,
12221 /*ESpecRange=*/SourceRange(),
12222 /*Exceptions=*/nullptr,
12223 /*ExceptionRanges=*/nullptr,
12224 /*NumExceptions=*/0,
12225 /*NoexceptExpr=*/nullptr,
12226 /*ExceptionSpecTokens=*/nullptr,
12227 /*DeclsInPrototype=*/None,
12229 DS.getAttributes(),
12231 D.SetIdentifier(&II, Loc);
12233 // Insert this function into translation-unit scope.
12235 DeclContext *PrevDC = CurContext;
12236 CurContext = Context.getTranslationUnitDecl();
12238 FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(TUScope, D));
12241 CurContext = PrevDC;
12243 AddKnownFunctionAttributes(FD);
12248 /// \brief Adds any function attributes that we know a priori based on
12249 /// the declaration of this function.
12251 /// These attributes can apply both to implicitly-declared builtins
12252 /// (like __builtin___printf_chk) or to library-declared functions
12253 /// like NSLog or printf.
12255 /// We need to check for duplicate attributes both here and where user-written
12256 /// attributes are applied to declarations.
12257 void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) {
12258 if (FD->isInvalidDecl())
12261 // If this is a built-in function, map its builtin attributes to
12262 // actual attributes.
12263 if (unsigned BuiltinID = FD->getBuiltinID()) {
12264 // Handle printf-formatting attributes.
12265 unsigned FormatIdx;
12267 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) {
12268 if (!FD->hasAttr<FormatAttr>()) {
12269 const char *fmt = "printf";
12270 unsigned int NumParams = FD->getNumParams();
12271 if (FormatIdx < NumParams && // NumParams may be 0 (e.g. vfprintf)
12272 FD->getParamDecl(FormatIdx)->getType()->isObjCObjectPointerType())
12274 FD->addAttr(FormatAttr::CreateImplicit(Context,
12275 &Context.Idents.get(fmt),
12277 HasVAListArg ? 0 : FormatIdx+2,
12278 FD->getLocation()));
12281 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx,
12283 if (!FD->hasAttr<FormatAttr>())
12284 FD->addAttr(FormatAttr::CreateImplicit(Context,
12285 &Context.Idents.get("scanf"),
12287 HasVAListArg ? 0 : FormatIdx+2,
12288 FD->getLocation()));
12291 // Mark const if we don't care about errno and that is the only
12292 // thing preventing the function from being const. This allows
12293 // IRgen to use LLVM intrinsics for such functions.
12294 if (!getLangOpts().MathErrno &&
12295 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) {
12296 if (!FD->hasAttr<ConstAttr>())
12297 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
12300 if (Context.BuiltinInfo.isReturnsTwice(BuiltinID) &&
12301 !FD->hasAttr<ReturnsTwiceAttr>())
12302 FD->addAttr(ReturnsTwiceAttr::CreateImplicit(Context,
12303 FD->getLocation()));
12304 if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->hasAttr<NoThrowAttr>())
12305 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
12306 if (Context.BuiltinInfo.isPure(BuiltinID) && !FD->hasAttr<PureAttr>())
12307 FD->addAttr(PureAttr::CreateImplicit(Context, FD->getLocation()));
12308 if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->hasAttr<ConstAttr>())
12309 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
12310 if (getLangOpts().CUDA && Context.BuiltinInfo.isTSBuiltin(BuiltinID) &&
12311 !FD->hasAttr<CUDADeviceAttr>() && !FD->hasAttr<CUDAHostAttr>()) {
12312 // Add the appropriate attribute, depending on the CUDA compilation mode
12313 // and which target the builtin belongs to. For example, during host
12314 // compilation, aux builtins are __device__, while the rest are __host__.
12315 if (getLangOpts().CUDAIsDevice !=
12316 Context.BuiltinInfo.isAuxBuiltinID(BuiltinID))
12317 FD->addAttr(CUDADeviceAttr::CreateImplicit(Context, FD->getLocation()));
12319 FD->addAttr(CUDAHostAttr::CreateImplicit(Context, FD->getLocation()));
12323 // If C++ exceptions are enabled but we are told extern "C" functions cannot
12324 // throw, add an implicit nothrow attribute to any extern "C" function we come
12326 if (getLangOpts().CXXExceptions && getLangOpts().ExternCNoUnwind &&
12327 FD->isExternC() && !FD->hasAttr<NoThrowAttr>()) {
12328 const auto *FPT = FD->getType()->getAs<FunctionProtoType>();
12329 if (!FPT || FPT->getExceptionSpecType() == EST_None)
12330 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
12333 IdentifierInfo *Name = FD->getIdentifier();
12336 if ((!getLangOpts().CPlusPlus &&
12337 FD->getDeclContext()->isTranslationUnit()) ||
12338 (isa<LinkageSpecDecl>(FD->getDeclContext()) &&
12339 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() ==
12340 LinkageSpecDecl::lang_c)) {
12341 // Okay: this could be a libc/libm/Objective-C function we know
12346 if (Name->isStr("asprintf") || Name->isStr("vasprintf")) {
12347 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be
12348 // target-specific builtins, perhaps?
12349 if (!FD->hasAttr<FormatAttr>())
12350 FD->addAttr(FormatAttr::CreateImplicit(Context,
12351 &Context.Idents.get("printf"), 2,
12352 Name->isStr("vasprintf") ? 0 : 3,
12353 FD->getLocation()));
12356 if (Name->isStr("__CFStringMakeConstantString")) {
12357 // We already have a __builtin___CFStringMakeConstantString,
12358 // but builds that use -fno-constant-cfstrings don't go through that.
12359 if (!FD->hasAttr<FormatArgAttr>())
12360 FD->addAttr(FormatArgAttr::CreateImplicit(Context, 1,
12361 FD->getLocation()));
12365 TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
12366 TypeSourceInfo *TInfo) {
12367 assert(D.getIdentifier() && "Wrong callback for declspec without declarator");
12368 assert(!T.isNull() && "GetTypeForDeclarator() returned null type");
12371 assert(D.isInvalidType() && "no declarator info for valid type");
12372 TInfo = Context.getTrivialTypeSourceInfo(T);
12375 // Scope manipulation handled by caller.
12376 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext,
12378 D.getIdentifierLoc(),
12382 // Bail out immediately if we have an invalid declaration.
12383 if (D.isInvalidType()) {
12384 NewTD->setInvalidDecl();
12388 if (D.getDeclSpec().isModulePrivateSpecified()) {
12389 if (CurContext->isFunctionOrMethod())
12390 Diag(NewTD->getLocation(), diag::err_module_private_local)
12391 << 2 << NewTD->getDeclName()
12392 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
12393 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
12395 NewTD->setModulePrivate();
12398 // C++ [dcl.typedef]p8:
12399 // If the typedef declaration defines an unnamed class (or
12400 // enum), the first typedef-name declared by the declaration
12401 // to be that class type (or enum type) is used to denote the
12402 // class type (or enum type) for linkage purposes only.
12403 // We need to check whether the type was declared in the declaration.
12404 switch (D.getDeclSpec().getTypeSpecType()) {
12407 case TST_interface:
12410 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
12411 setTagNameForLinkagePurposes(tagFromDeclSpec, NewTD);
12422 /// \brief Check that this is a valid underlying type for an enum declaration.
12423 bool Sema::CheckEnumUnderlyingType(TypeSourceInfo *TI) {
12424 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
12425 QualType T = TI->getType();
12427 if (T->isDependentType())
12430 if (const BuiltinType *BT = T->getAs<BuiltinType>())
12431 if (BT->isInteger())
12434 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) << T;
12438 /// Check whether this is a valid redeclaration of a previous enumeration.
12439 /// \return true if the redeclaration was invalid.
12440 bool Sema::CheckEnumRedeclaration(
12441 SourceLocation EnumLoc, bool IsScoped, QualType EnumUnderlyingTy,
12442 bool EnumUnderlyingIsImplicit, const EnumDecl *Prev) {
12443 bool IsFixed = !EnumUnderlyingTy.isNull();
12445 if (IsScoped != Prev->isScoped()) {
12446 Diag(EnumLoc, diag::err_enum_redeclare_scoped_mismatch)
12447 << Prev->isScoped();
12448 Diag(Prev->getLocation(), diag::note_previous_declaration);
12452 if (IsFixed && Prev->isFixed()) {
12453 if (!EnumUnderlyingTy->isDependentType() &&
12454 !Prev->getIntegerType()->isDependentType() &&
12455 !Context.hasSameUnqualifiedType(EnumUnderlyingTy,
12456 Prev->getIntegerType())) {
12457 // TODO: Highlight the underlying type of the redeclaration.
12458 Diag(EnumLoc, diag::err_enum_redeclare_type_mismatch)
12459 << EnumUnderlyingTy << Prev->getIntegerType();
12460 Diag(Prev->getLocation(), diag::note_previous_declaration)
12461 << Prev->getIntegerTypeRange();
12464 } else if (IsFixed && !Prev->isFixed() && EnumUnderlyingIsImplicit) {
12466 } else if (!IsFixed && Prev->isFixed() && !Prev->getIntegerTypeSourceInfo()) {
12468 } else if (IsFixed != Prev->isFixed()) {
12469 Diag(EnumLoc, diag::err_enum_redeclare_fixed_mismatch)
12470 << Prev->isFixed();
12471 Diag(Prev->getLocation(), diag::note_previous_declaration);
12478 /// \brief Get diagnostic %select index for tag kind for
12479 /// redeclaration diagnostic message.
12480 /// WARNING: Indexes apply to particular diagnostics only!
12482 /// \returns diagnostic %select index.
12483 static unsigned getRedeclDiagFromTagKind(TagTypeKind Tag) {
12485 case TTK_Struct: return 0;
12486 case TTK_Interface: return 1;
12487 case TTK_Class: return 2;
12488 default: llvm_unreachable("Invalid tag kind for redecl diagnostic!");
12492 /// \brief Determine if tag kind is a class-key compatible with
12493 /// class for redeclaration (class, struct, or __interface).
12495 /// \returns true iff the tag kind is compatible.
12496 static bool isClassCompatTagKind(TagTypeKind Tag)
12498 return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface;
12501 Sema::NonTagKind Sema::getNonTagTypeDeclKind(const Decl *PrevDecl,
12503 if (isa<TypedefDecl>(PrevDecl))
12504 return NTK_Typedef;
12505 else if (isa<TypeAliasDecl>(PrevDecl))
12506 return NTK_TypeAlias;
12507 else if (isa<ClassTemplateDecl>(PrevDecl))
12508 return NTK_Template;
12509 else if (isa<TypeAliasTemplateDecl>(PrevDecl))
12510 return NTK_TypeAliasTemplate;
12511 else if (isa<TemplateTemplateParmDecl>(PrevDecl))
12512 return NTK_TemplateTemplateArgument;
12515 case TTK_Interface:
12517 return getLangOpts().CPlusPlus ? NTK_NonClass : NTK_NonStruct;
12519 return NTK_NonUnion;
12521 return NTK_NonEnum;
12523 llvm_unreachable("invalid TTK");
12526 /// \brief Determine whether a tag with a given kind is acceptable
12527 /// as a redeclaration of the given tag declaration.
12529 /// \returns true if the new tag kind is acceptable, false otherwise.
12530 bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous,
12531 TagTypeKind NewTag, bool isDefinition,
12532 SourceLocation NewTagLoc,
12533 const IdentifierInfo *Name) {
12534 // C++ [dcl.type.elab]p3:
12535 // The class-key or enum keyword present in the
12536 // elaborated-type-specifier shall agree in kind with the
12537 // declaration to which the name in the elaborated-type-specifier
12538 // refers. This rule also applies to the form of
12539 // elaborated-type-specifier that declares a class-name or
12540 // friend class since it can be construed as referring to the
12541 // definition of the class. Thus, in any
12542 // elaborated-type-specifier, the enum keyword shall be used to
12543 // refer to an enumeration (7.2), the union class-key shall be
12544 // used to refer to a union (clause 9), and either the class or
12545 // struct class-key shall be used to refer to a class (clause 9)
12546 // declared using the class or struct class-key.
12547 TagTypeKind OldTag = Previous->getTagKind();
12548 if (!isDefinition || !isClassCompatTagKind(NewTag))
12549 if (OldTag == NewTag)
12552 if (isClassCompatTagKind(OldTag) && isClassCompatTagKind(NewTag)) {
12553 // Warn about the struct/class tag mismatch.
12554 bool isTemplate = false;
12555 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous))
12556 isTemplate = Record->getDescribedClassTemplate();
12558 if (!ActiveTemplateInstantiations.empty()) {
12559 // In a template instantiation, do not offer fix-its for tag mismatches
12560 // since they usually mess up the template instead of fixing the problem.
12561 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
12562 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12563 << getRedeclDiagFromTagKind(OldTag);
12567 if (isDefinition) {
12568 // On definitions, check previous tags and issue a fix-it for each
12569 // one that doesn't match the current tag.
12570 if (Previous->getDefinition()) {
12571 // Don't suggest fix-its for redefinitions.
12575 bool previousMismatch = false;
12576 for (auto I : Previous->redecls()) {
12577 if (I->getTagKind() != NewTag) {
12578 if (!previousMismatch) {
12579 previousMismatch = true;
12580 Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch)
12581 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12582 << getRedeclDiagFromTagKind(I->getTagKind());
12584 Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion)
12585 << getRedeclDiagFromTagKind(NewTag)
12586 << FixItHint::CreateReplacement(I->getInnerLocStart(),
12587 TypeWithKeyword::getTagTypeKindName(NewTag));
12593 // Check for a previous definition. If current tag and definition
12594 // are same type, do nothing. If no definition, but disagree with
12595 // with previous tag type, give a warning, but no fix-it.
12596 const TagDecl *Redecl = Previous->getDefinition() ?
12597 Previous->getDefinition() : Previous;
12598 if (Redecl->getTagKind() == NewTag) {
12602 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
12603 << getRedeclDiagFromTagKind(NewTag) << isTemplate << Name
12604 << getRedeclDiagFromTagKind(OldTag);
12605 Diag(Redecl->getLocation(), diag::note_previous_use);
12607 // If there is a previous definition, suggest a fix-it.
12608 if (Previous->getDefinition()) {
12609 Diag(NewTagLoc, diag::note_struct_class_suggestion)
12610 << getRedeclDiagFromTagKind(Redecl->getTagKind())
12611 << FixItHint::CreateReplacement(SourceRange(NewTagLoc),
12612 TypeWithKeyword::getTagTypeKindName(Redecl->getTagKind()));
12620 /// Add a minimal nested name specifier fixit hint to allow lookup of a tag name
12621 /// from an outer enclosing namespace or file scope inside a friend declaration.
12622 /// This should provide the commented out code in the following snippet:
12626 /// struct Y { friend struct /*N::*/ X; };
12629 static FixItHint createFriendTagNNSFixIt(Sema &SemaRef, NamedDecl *ND, Scope *S,
12630 SourceLocation NameLoc) {
12631 // While the decl is in a namespace, do repeated lookup of that name and see
12632 // if we get the same namespace back. If we do not, continue until
12633 // translation unit scope, at which point we have a fully qualified NNS.
12634 SmallVector<IdentifierInfo *, 4> Namespaces;
12635 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
12636 for (; !DC->isTranslationUnit(); DC = DC->getParent()) {
12637 // This tag should be declared in a namespace, which can only be enclosed by
12638 // other namespaces. Bail if there's an anonymous namespace in the chain.
12639 NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(DC);
12640 if (!Namespace || Namespace->isAnonymousNamespace())
12641 return FixItHint();
12642 IdentifierInfo *II = Namespace->getIdentifier();
12643 Namespaces.push_back(II);
12644 NamedDecl *Lookup = SemaRef.LookupSingleName(
12645 S, II, NameLoc, Sema::LookupNestedNameSpecifierName);
12646 if (Lookup == Namespace)
12650 // Once we have all the namespaces, reverse them to go outermost first, and
12652 SmallString<64> Insertion;
12653 llvm::raw_svector_ostream OS(Insertion);
12654 if (DC->isTranslationUnit())
12656 std::reverse(Namespaces.begin(), Namespaces.end());
12657 for (auto *II : Namespaces)
12658 OS << II->getName() << "::";
12659 return FixItHint::CreateInsertion(NameLoc, Insertion);
12662 /// \brief Determine whether a tag originally declared in context \p OldDC can
12663 /// be redeclared with an unqualfied name in \p NewDC (assuming name lookup
12664 /// found a declaration in \p OldDC as a previous decl, perhaps through a
12665 /// using-declaration).
12666 static bool isAcceptableTagRedeclContext(Sema &S, DeclContext *OldDC,
12667 DeclContext *NewDC) {
12668 OldDC = OldDC->getRedeclContext();
12669 NewDC = NewDC->getRedeclContext();
12671 if (OldDC->Equals(NewDC))
12674 // In MSVC mode, we allow a redeclaration if the contexts are related (either
12675 // encloses the other).
12676 if (S.getLangOpts().MSVCCompat &&
12677 (OldDC->Encloses(NewDC) || NewDC->Encloses(OldDC)))
12683 /// \brief This is invoked when we see 'struct foo' or 'struct {'. In the
12684 /// former case, Name will be non-null. In the later case, Name will be null.
12685 /// TagSpec indicates what kind of tag this is. TUK indicates whether this is a
12686 /// reference/declaration/definition of a tag.
12688 /// \param IsTypeSpecifier \c true if this is a type-specifier (or
12689 /// trailing-type-specifier) other than one in an alias-declaration.
12691 /// \param SkipBody If non-null, will be set to indicate if the caller should
12692 /// skip the definition of this tag and treat it as if it were a declaration.
12693 Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
12694 SourceLocation KWLoc, CXXScopeSpec &SS,
12695 IdentifierInfo *Name, SourceLocation NameLoc,
12696 AttributeList *Attr, AccessSpecifier AS,
12697 SourceLocation ModulePrivateLoc,
12698 MultiTemplateParamsArg TemplateParameterLists,
12699 bool &OwnedDecl, bool &IsDependent,
12700 SourceLocation ScopedEnumKWLoc,
12701 bool ScopedEnumUsesClassTag,
12702 TypeResult UnderlyingType,
12703 bool IsTypeSpecifier, SkipBodyInfo *SkipBody) {
12704 // If this is not a definition, it must have a name.
12705 IdentifierInfo *OrigName = Name;
12706 assert((Name != nullptr || TUK == TUK_Definition) &&
12707 "Nameless record must be a definition!");
12708 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference);
12711 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
12712 bool ScopedEnum = ScopedEnumKWLoc.isValid();
12714 // FIXME: Check explicit specializations more carefully.
12715 bool isExplicitSpecialization = false;
12716 bool Invalid = false;
12718 // We only need to do this matching if we have template parameters
12719 // or a scope specifier, which also conveniently avoids this work
12720 // for non-C++ cases.
12721 if (TemplateParameterLists.size() > 0 ||
12722 (SS.isNotEmpty() && TUK != TUK_Reference)) {
12723 if (TemplateParameterList *TemplateParams =
12724 MatchTemplateParametersToScopeSpecifier(
12725 KWLoc, NameLoc, SS, nullptr, TemplateParameterLists,
12726 TUK == TUK_Friend, isExplicitSpecialization, Invalid)) {
12727 if (Kind == TTK_Enum) {
12728 Diag(KWLoc, diag::err_enum_template);
12732 if (TemplateParams->size() > 0) {
12733 // This is a declaration or definition of a class template (which may
12734 // be a member of another template).
12740 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc,
12741 SS, Name, NameLoc, Attr,
12742 TemplateParams, AS,
12744 /*FriendLoc*/SourceLocation(),
12745 TemplateParameterLists.size()-1,
12746 TemplateParameterLists.data(),
12748 return Result.get();
12750 // The "template<>" header is extraneous.
12751 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
12752 << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
12753 isExplicitSpecialization = true;
12758 // Figure out the underlying type if this a enum declaration. We need to do
12759 // this early, because it's needed to detect if this is an incompatible
12761 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying;
12762 bool EnumUnderlyingIsImplicit = false;
12764 if (Kind == TTK_Enum) {
12765 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum))
12766 // No underlying type explicitly specified, or we failed to parse the
12767 // type, default to int.
12768 EnumUnderlying = Context.IntTy.getTypePtr();
12769 else if (UnderlyingType.get()) {
12770 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
12771 // integral type; any cv-qualification is ignored.
12772 TypeSourceInfo *TI = nullptr;
12773 GetTypeFromParser(UnderlyingType.get(), &TI);
12774 EnumUnderlying = TI;
12776 if (CheckEnumUnderlyingType(TI))
12777 // Recover by falling back to int.
12778 EnumUnderlying = Context.IntTy.getTypePtr();
12780 if (DiagnoseUnexpandedParameterPack(TI->getTypeLoc().getBeginLoc(), TI,
12781 UPPC_FixedUnderlyingType))
12782 EnumUnderlying = Context.IntTy.getTypePtr();
12784 } else if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
12785 if (getLangOpts().MSVCCompat || TUK == TUK_Definition) {
12786 // Microsoft enums are always of int type.
12787 EnumUnderlying = Context.IntTy.getTypePtr();
12788 EnumUnderlyingIsImplicit = true;
12793 DeclContext *SearchDC = CurContext;
12794 DeclContext *DC = CurContext;
12795 bool isStdBadAlloc = false;
12796 bool isStdAlignValT = false;
12798 RedeclarationKind Redecl = ForRedeclaration;
12799 if (TUK == TUK_Friend || TUK == TUK_Reference)
12800 Redecl = NotForRedeclaration;
12802 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl);
12803 if (Name && SS.isNotEmpty()) {
12804 // We have a nested-name tag ('struct foo::bar').
12806 // Check for invalid 'foo::'.
12807 if (SS.isInvalid()) {
12809 goto CreateNewDecl;
12812 // If this is a friend or a reference to a class in a dependent
12813 // context, don't try to make a decl for it.
12814 if (TUK == TUK_Friend || TUK == TUK_Reference) {
12815 DC = computeDeclContext(SS, false);
12817 IsDependent = true;
12821 DC = computeDeclContext(SS, true);
12823 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec)
12829 if (RequireCompleteDeclContext(SS, DC))
12833 // Look-up name inside 'foo::'.
12834 LookupQualifiedName(Previous, DC);
12836 if (Previous.isAmbiguous())
12839 if (Previous.empty()) {
12840 // Name lookup did not find anything. However, if the
12841 // nested-name-specifier refers to the current instantiation,
12842 // and that current instantiation has any dependent base
12843 // classes, we might find something at instantiation time: treat
12844 // this as a dependent elaborated-type-specifier.
12845 // But this only makes any sense for reference-like lookups.
12846 if (Previous.wasNotFoundInCurrentInstantiation() &&
12847 (TUK == TUK_Reference || TUK == TUK_Friend)) {
12848 IsDependent = true;
12852 // A tag 'foo::bar' must already exist.
12853 Diag(NameLoc, diag::err_not_tag_in_scope)
12854 << Kind << Name << DC << SS.getRange();
12857 goto CreateNewDecl;
12860 // C++14 [class.mem]p14:
12861 // If T is the name of a class, then each of the following shall have a
12862 // name different from T:
12863 // -- every member of class T that is itself a type
12864 if (TUK != TUK_Reference && TUK != TUK_Friend &&
12865 DiagnoseClassNameShadow(SearchDC, DeclarationNameInfo(Name, NameLoc)))
12868 // If this is a named struct, check to see if there was a previous forward
12869 // declaration or definition.
12870 // FIXME: We're looking into outer scopes here, even when we
12871 // shouldn't be. Doing so can result in ambiguities that we
12872 // shouldn't be diagnosing.
12873 LookupName(Previous, S);
12875 // When declaring or defining a tag, ignore ambiguities introduced
12876 // by types using'ed into this scope.
12877 if (Previous.isAmbiguous() &&
12878 (TUK == TUK_Definition || TUK == TUK_Declaration)) {
12879 LookupResult::Filter F = Previous.makeFilter();
12880 while (F.hasNext()) {
12881 NamedDecl *ND = F.next();
12882 if (!ND->getDeclContext()->getRedeclContext()->Equals(
12883 SearchDC->getRedeclContext()))
12889 // C++11 [namespace.memdef]p3:
12890 // If the name in a friend declaration is neither qualified nor
12891 // a template-id and the declaration is a function or an
12892 // elaborated-type-specifier, the lookup to determine whether
12893 // the entity has been previously declared shall not consider
12894 // any scopes outside the innermost enclosing namespace.
12896 // MSVC doesn't implement the above rule for types, so a friend tag
12897 // declaration may be a redeclaration of a type declared in an enclosing
12898 // scope. They do implement this rule for friend functions.
12900 // Does it matter that this should be by scope instead of by
12901 // semantic context?
12902 if (!Previous.empty() && TUK == TUK_Friend) {
12903 DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext();
12904 LookupResult::Filter F = Previous.makeFilter();
12905 bool FriendSawTagOutsideEnclosingNamespace = false;
12906 while (F.hasNext()) {
12907 NamedDecl *ND = F.next();
12908 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
12909 if (DC->isFileContext() &&
12910 !EnclosingNS->Encloses(ND->getDeclContext())) {
12911 if (getLangOpts().MSVCCompat)
12912 FriendSawTagOutsideEnclosingNamespace = true;
12919 // Diagnose this MSVC extension in the easy case where lookup would have
12920 // unambiguously found something outside the enclosing namespace.
12921 if (Previous.isSingleResult() && FriendSawTagOutsideEnclosingNamespace) {
12922 NamedDecl *ND = Previous.getFoundDecl();
12923 Diag(NameLoc, diag::ext_friend_tag_redecl_outside_namespace)
12924 << createFriendTagNNSFixIt(*this, ND, S, NameLoc);
12928 // Note: there used to be some attempt at recovery here.
12929 if (Previous.isAmbiguous())
12932 if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) {
12933 // FIXME: This makes sure that we ignore the contexts associated
12934 // with C structs, unions, and enums when looking for a matching
12935 // tag declaration or definition. See the similar lookup tweak
12936 // in Sema::LookupName; is there a better way to deal with this?
12937 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
12938 SearchDC = SearchDC->getParent();
12942 if (Previous.isSingleResult() &&
12943 Previous.getFoundDecl()->isTemplateParameter()) {
12944 // Maybe we will complain about the shadowed template parameter.
12945 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
12946 // Just pretend that we didn't see the previous declaration.
12950 if (getLangOpts().CPlusPlus && Name && DC && StdNamespace &&
12951 DC->Equals(getStdNamespace())) {
12952 if (Name->isStr("bad_alloc")) {
12953 // This is a declaration of or a reference to "std::bad_alloc".
12954 isStdBadAlloc = true;
12956 // If std::bad_alloc has been implicitly declared (but made invisible to
12957 // name lookup), fill in this implicit declaration as the previous
12958 // declaration, so that the declarations get chained appropriately.
12959 if (Previous.empty() && StdBadAlloc)
12960 Previous.addDecl(getStdBadAlloc());
12961 } else if (Name->isStr("align_val_t")) {
12962 isStdAlignValT = true;
12963 if (Previous.empty() && StdAlignValT)
12964 Previous.addDecl(getStdAlignValT());
12968 // If we didn't find a previous declaration, and this is a reference
12969 // (or friend reference), move to the correct scope. In C++, we
12970 // also need to do a redeclaration lookup there, just in case
12971 // there's a shadow friend decl.
12972 if (Name && Previous.empty() &&
12973 (TUK == TUK_Reference || TUK == TUK_Friend)) {
12974 if (Invalid) goto CreateNewDecl;
12975 assert(SS.isEmpty());
12977 if (TUK == TUK_Reference) {
12978 // C++ [basic.scope.pdecl]p5:
12979 // -- for an elaborated-type-specifier of the form
12981 // class-key identifier
12983 // if the elaborated-type-specifier is used in the
12984 // decl-specifier-seq or parameter-declaration-clause of a
12985 // function defined in namespace scope, the identifier is
12986 // declared as a class-name in the namespace that contains
12987 // the declaration; otherwise, except as a friend
12988 // declaration, the identifier is declared in the smallest
12989 // non-class, non-function-prototype scope that contains the
12992 // C99 6.7.2.3p8 has a similar (but not identical!) provision for
12993 // C structs and unions.
12995 // It is an error in C++ to declare (rather than define) an enum
12996 // type, including via an elaborated type specifier. We'll
12997 // diagnose that later; for now, declare the enum in the same
12998 // scope as we would have picked for any other tag type.
13000 // GNU C also supports this behavior as part of its incomplete
13001 // enum types extension, while GNU C++ does not.
13003 // Find the context where we'll be declaring the tag.
13004 // FIXME: We would like to maintain the current DeclContext as the
13005 // lexical context,
13006 SearchDC = getTagInjectionContext(SearchDC);
13008 // Find the scope where we'll be declaring the tag.
13009 S = getTagInjectionScope(S, getLangOpts());
13011 assert(TUK == TUK_Friend);
13012 // C++ [namespace.memdef]p3:
13013 // If a friend declaration in a non-local class first declares a
13014 // class or function, the friend class or function is a member of
13015 // the innermost enclosing namespace.
13016 SearchDC = SearchDC->getEnclosingNamespaceContext();
13019 // In C++, we need to do a redeclaration lookup to properly
13020 // diagnose some problems.
13021 // FIXME: redeclaration lookup is also used (with and without C++) to find a
13022 // hidden declaration so that we don't get ambiguity errors when using a
13023 // type declared by an elaborated-type-specifier. In C that is not correct
13024 // and we should instead merge compatible types found by lookup.
13025 if (getLangOpts().CPlusPlus) {
13026 Previous.setRedeclarationKind(ForRedeclaration);
13027 LookupQualifiedName(Previous, SearchDC);
13029 Previous.setRedeclarationKind(ForRedeclaration);
13030 LookupName(Previous, S);
13034 // If we have a known previous declaration to use, then use it.
13035 if (Previous.empty() && SkipBody && SkipBody->Previous)
13036 Previous.addDecl(SkipBody->Previous);
13038 if (!Previous.empty()) {
13039 NamedDecl *PrevDecl = Previous.getFoundDecl();
13040 NamedDecl *DirectPrevDecl = Previous.getRepresentativeDecl();
13042 // It's okay to have a tag decl in the same scope as a typedef
13043 // which hides a tag decl in the same scope. Finding this
13044 // insanity with a redeclaration lookup can only actually happen
13047 // This is also okay for elaborated-type-specifiers, which is
13048 // technically forbidden by the current standard but which is
13049 // okay according to the likely resolution of an open issue;
13050 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
13051 if (getLangOpts().CPlusPlus) {
13052 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
13053 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
13054 TagDecl *Tag = TT->getDecl();
13055 if (Tag->getDeclName() == Name &&
13056 Tag->getDeclContext()->getRedeclContext()
13057 ->Equals(TD->getDeclContext()->getRedeclContext())) {
13060 Previous.addDecl(Tag);
13061 Previous.resolveKind();
13067 // If this is a redeclaration of a using shadow declaration, it must
13068 // declare a tag in the same context. In MSVC mode, we allow a
13069 // redefinition if either context is within the other.
13070 if (auto *Shadow = dyn_cast<UsingShadowDecl>(DirectPrevDecl)) {
13071 auto *OldTag = dyn_cast<TagDecl>(PrevDecl);
13072 if (SS.isEmpty() && TUK != TUK_Reference && TUK != TUK_Friend &&
13073 isDeclInScope(Shadow, SearchDC, S, isExplicitSpecialization) &&
13074 !(OldTag && isAcceptableTagRedeclContext(
13075 *this, OldTag->getDeclContext(), SearchDC))) {
13076 Diag(KWLoc, diag::err_using_decl_conflict_reverse);
13077 Diag(Shadow->getTargetDecl()->getLocation(),
13078 diag::note_using_decl_target);
13079 Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl)
13081 // Recover by ignoring the old declaration.
13083 goto CreateNewDecl;
13087 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
13088 // If this is a use of a previous tag, or if the tag is already declared
13089 // in the same scope (so that the definition/declaration completes or
13090 // rementions the tag), reuse the decl.
13091 if (TUK == TUK_Reference || TUK == TUK_Friend ||
13092 isDeclInScope(DirectPrevDecl, SearchDC, S,
13093 SS.isNotEmpty() || isExplicitSpecialization)) {
13094 // Make sure that this wasn't declared as an enum and now used as a
13095 // struct or something similar.
13096 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind,
13097 TUK == TUK_Definition, KWLoc,
13099 bool SafeToContinue
13100 = (PrevTagDecl->getTagKind() != TTK_Enum &&
13102 if (SafeToContinue)
13103 Diag(KWLoc, diag::err_use_with_wrong_tag)
13105 << FixItHint::CreateReplacement(SourceRange(KWLoc),
13106 PrevTagDecl->getKindName());
13108 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
13109 Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
13111 if (SafeToContinue)
13112 Kind = PrevTagDecl->getTagKind();
13114 // Recover by making this an anonymous redefinition.
13121 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
13122 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);
13124 // If this is an elaborated-type-specifier for a scoped enumeration,
13125 // the 'class' keyword is not necessary and not permitted.
13126 if (TUK == TUK_Reference || TUK == TUK_Friend) {
13128 Diag(ScopedEnumKWLoc, diag::err_enum_class_reference)
13129 << PrevEnum->isScoped()
13130 << FixItHint::CreateRemoval(ScopedEnumKWLoc);
13131 return PrevTagDecl;
13134 QualType EnumUnderlyingTy;
13135 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
13136 EnumUnderlyingTy = TI->getType().getUnqualifiedType();
13137 else if (const Type *T = EnumUnderlying.dyn_cast<const Type*>())
13138 EnumUnderlyingTy = QualType(T, 0);
13140 // All conflicts with previous declarations are recovered by
13141 // returning the previous declaration, unless this is a definition,
13142 // in which case we want the caller to bail out.
13143 if (CheckEnumRedeclaration(NameLoc.isValid() ? NameLoc : KWLoc,
13144 ScopedEnum, EnumUnderlyingTy,
13145 EnumUnderlyingIsImplicit, PrevEnum))
13146 return TUK == TUK_Declaration ? PrevTagDecl : nullptr;
13149 // C++11 [class.mem]p1:
13150 // A member shall not be declared twice in the member-specification,
13151 // except that a nested class or member class template can be declared
13152 // and then later defined.
13153 if (TUK == TUK_Declaration && PrevDecl->isCXXClassMember() &&
13154 S->isDeclScope(PrevDecl)) {
13155 Diag(NameLoc, diag::ext_member_redeclared);
13156 Diag(PrevTagDecl->getLocation(), diag::note_previous_declaration);
13160 // If this is a use, just return the declaration we found, unless
13161 // we have attributes.
13162 if (TUK == TUK_Reference || TUK == TUK_Friend) {
13164 // FIXME: Diagnose these attributes. For now, we create a new
13165 // declaration to hold them.
13166 } else if (TUK == TUK_Reference &&
13167 (PrevTagDecl->getFriendObjectKind() ==
13168 Decl::FOK_Undeclared ||
13169 PP.getModuleContainingLocation(
13170 PrevDecl->getLocation()) !=
13171 PP.getModuleContainingLocation(KWLoc)) &&
13173 // This declaration is a reference to an existing entity, but
13174 // has different visibility from that entity: it either makes
13175 // a friend visible or it makes a type visible in a new module.
13176 // In either case, create a new declaration. We only do this if
13177 // the declaration would have meant the same thing if no prior
13178 // declaration were found, that is, if it was found in the same
13179 // scope where we would have injected a declaration.
13180 if (!getTagInjectionContext(CurContext)->getRedeclContext()
13181 ->Equals(PrevDecl->getDeclContext()->getRedeclContext()))
13182 return PrevTagDecl;
13183 // This is in the injected scope, create a new declaration in
13185 S = getTagInjectionScope(S, getLangOpts());
13187 return PrevTagDecl;
13191 // Diagnose attempts to redefine a tag.
13192 if (TUK == TUK_Definition) {
13193 if (NamedDecl *Def = PrevTagDecl->getDefinition()) {
13194 // If we're defining a specialization and the previous definition
13195 // is from an implicit instantiation, don't emit an error
13196 // here; we'll catch this in the general case below.
13197 bool IsExplicitSpecializationAfterInstantiation = false;
13198 if (isExplicitSpecialization) {
13199 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Def))
13200 IsExplicitSpecializationAfterInstantiation =
13201 RD->getTemplateSpecializationKind() !=
13202 TSK_ExplicitSpecialization;
13203 else if (EnumDecl *ED = dyn_cast<EnumDecl>(Def))
13204 IsExplicitSpecializationAfterInstantiation =
13205 ED->getTemplateSpecializationKind() !=
13206 TSK_ExplicitSpecialization;
13209 NamedDecl *Hidden = nullptr;
13210 if (SkipBody && getLangOpts().CPlusPlus &&
13211 !hasVisibleDefinition(Def, &Hidden)) {
13212 // There is a definition of this tag, but it is not visible. We
13213 // explicitly make use of C++'s one definition rule here, and
13214 // assume that this definition is identical to the hidden one
13215 // we already have. Make the existing definition visible and
13216 // use it in place of this one.
13217 SkipBody->ShouldSkip = true;
13218 makeMergedDefinitionVisible(Hidden, KWLoc);
13220 } else if (!IsExplicitSpecializationAfterInstantiation) {
13221 // A redeclaration in function prototype scope in C isn't
13222 // visible elsewhere, so merely issue a warning.
13223 if (!getLangOpts().CPlusPlus && S->containedInPrototypeScope())
13224 Diag(NameLoc, diag::warn_redefinition_in_param_list) << Name;
13226 Diag(NameLoc, diag::err_redefinition) << Name;
13227 Diag(Def->getLocation(), diag::note_previous_definition);
13228 // If this is a redefinition, recover by making this
13229 // struct be anonymous, which will make any later
13230 // references get the previous definition.
13236 // If the type is currently being defined, complain
13237 // about a nested redefinition.
13238 auto *TD = Context.getTagDeclType(PrevTagDecl)->getAsTagDecl();
13239 if (TD->isBeingDefined()) {
13240 Diag(NameLoc, diag::err_nested_redefinition) << Name;
13241 Diag(PrevTagDecl->getLocation(),
13242 diag::note_previous_definition);
13249 // Okay, this is definition of a previously declared or referenced
13250 // tag. We're going to create a new Decl for it.
13253 // Okay, we're going to make a redeclaration. If this is some kind
13254 // of reference, make sure we build the redeclaration in the same DC
13255 // as the original, and ignore the current access specifier.
13256 if (TUK == TUK_Friend || TUK == TUK_Reference) {
13257 SearchDC = PrevTagDecl->getDeclContext();
13261 // If we get here we have (another) forward declaration or we
13262 // have a definition. Just create a new decl.
13265 // If we get here, this is a definition of a new tag type in a nested
13266 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a
13267 // new decl/type. We set PrevDecl to NULL so that the entities
13268 // have distinct types.
13271 // If we get here, we're going to create a new Decl. If PrevDecl
13272 // is non-NULL, it's a definition of the tag declared by
13273 // PrevDecl. If it's NULL, we have a new definition.
13275 // Otherwise, PrevDecl is not a tag, but was found with tag
13276 // lookup. This is only actually possible in C++, where a few
13277 // things like templates still live in the tag namespace.
13279 // Use a better diagnostic if an elaborated-type-specifier
13280 // found the wrong kind of type on the first
13281 // (non-redeclaration) lookup.
13282 if ((TUK == TUK_Reference || TUK == TUK_Friend) &&
13283 !Previous.isForRedeclaration()) {
13284 NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl, Kind);
13285 Diag(NameLoc, diag::err_tag_reference_non_tag) << PrevDecl << NTK
13287 Diag(PrevDecl->getLocation(), diag::note_declared_at);
13290 // Otherwise, only diagnose if the declaration is in scope.
13291 } else if (!isDeclInScope(DirectPrevDecl, SearchDC, S,
13292 SS.isNotEmpty() || isExplicitSpecialization)) {
13295 // Diagnose implicit declarations introduced by elaborated types.
13296 } else if (TUK == TUK_Reference || TUK == TUK_Friend) {
13297 NonTagKind NTK = getNonTagTypeDeclKind(PrevDecl, Kind);
13298 Diag(NameLoc, diag::err_tag_reference_conflict) << NTK;
13299 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
13302 // Otherwise it's a declaration. Call out a particularly common
13304 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
13306 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
13307 Diag(NameLoc, diag::err_tag_definition_of_typedef)
13308 << Name << Kind << TND->getUnderlyingType();
13309 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
13312 // Otherwise, diagnose.
13314 // The tag name clashes with something else in the target scope,
13315 // issue an error and recover by making this tag be anonymous.
13316 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
13317 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
13322 // The existing declaration isn't relevant to us; we're in a
13323 // new scope, so clear out the previous declaration.
13330 TagDecl *PrevDecl = nullptr;
13331 if (Previous.isSingleResult())
13332 PrevDecl = cast<TagDecl>(Previous.getFoundDecl());
13334 // If there is an identifier, use the location of the identifier as the
13335 // location of the decl, otherwise use the location of the struct/union
13337 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc;
13339 // Otherwise, create a new declaration. If there is a previous
13340 // declaration of the same entity, the two will be linked via
13344 bool IsForwardReference = false;
13345 if (Kind == TTK_Enum) {
13346 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
13347 // enum X { A, B, C } D; D should chain to X.
13348 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name,
13349 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum,
13350 ScopedEnumUsesClassTag, !EnumUnderlying.isNull());
13352 if (isStdAlignValT && (!StdAlignValT || getStdAlignValT()->isImplicit()))
13353 StdAlignValT = cast<EnumDecl>(New);
13355 // If this is an undefined enum, warn.
13356 if (TUK != TUK_Definition && !Invalid) {
13358 if ((getLangOpts().CPlusPlus11 || getLangOpts().ObjC2) &&
13359 cast<EnumDecl>(New)->isFixed()) {
13360 // C++0x: 7.2p2: opaque-enum-declaration.
13361 // Conflicts are diagnosed above. Do nothing.
13363 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) {
13364 Diag(Loc, diag::ext_forward_ref_enum_def)
13366 Diag(Def->getLocation(), diag::note_previous_definition);
13368 unsigned DiagID = diag::ext_forward_ref_enum;
13369 if (getLangOpts().MSVCCompat)
13370 DiagID = diag::ext_ms_forward_ref_enum;
13371 else if (getLangOpts().CPlusPlus)
13372 DiagID = diag::err_forward_ref_enum;
13375 // If this is a forward-declared reference to an enumeration, make a
13376 // note of it; we won't actually be introducing the declaration into
13377 // the declaration context.
13378 if (TUK == TUK_Reference)
13379 IsForwardReference = true;
13383 if (EnumUnderlying) {
13384 EnumDecl *ED = cast<EnumDecl>(New);
13385 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
13386 ED->setIntegerTypeSourceInfo(TI);
13388 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
13389 ED->setPromotionType(ED->getIntegerType());
13392 // struct/union/class
13394 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
13395 // struct X { int A; } D; D should chain to X.
13396 if (getLangOpts().CPlusPlus) {
13397 // FIXME: Look for a way to use RecordDecl for simple structs.
13398 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
13399 cast_or_null<CXXRecordDecl>(PrevDecl));
13401 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit()))
13402 StdBadAlloc = cast<CXXRecordDecl>(New);
13404 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
13405 cast_or_null<RecordDecl>(PrevDecl));
13408 // C++11 [dcl.type]p3:
13409 // A type-specifier-seq shall not define a class or enumeration [...].
13410 if (getLangOpts().CPlusPlus && IsTypeSpecifier && TUK == TUK_Definition) {
13411 Diag(New->getLocation(), diag::err_type_defined_in_type_specifier)
13412 << Context.getTagDeclType(New);
13416 // Maybe add qualifier info.
13417 if (SS.isNotEmpty()) {
13419 // If this is either a declaration or a definition, check the
13420 // nested-name-specifier against the current context. We don't do this
13421 // for explicit specializations, because they have similar checking
13422 // (with more specific diagnostics) in the call to
13423 // CheckMemberSpecialization, below.
13424 if (!isExplicitSpecialization &&
13425 (TUK == TUK_Definition || TUK == TUK_Declaration) &&
13426 diagnoseQualifiedDeclaration(SS, DC, OrigName, Loc))
13429 New->setQualifierInfo(SS.getWithLocInContext(Context));
13430 if (TemplateParameterLists.size() > 0) {
13431 New->setTemplateParameterListsInfo(Context, TemplateParameterLists);
13438 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) {
13439 // Add alignment attributes if necessary; these attributes are checked when
13440 // the ASTContext lays out the structure.
13442 // It is important for implementing the correct semantics that this
13443 // happen here (in act on tag decl). The #pragma pack stack is
13444 // maintained as a result of parser callbacks which can occur at
13445 // many points during the parsing of a struct declaration (because
13446 // the #pragma tokens are effectively skipped over during the
13447 // parsing of the struct).
13448 if (TUK == TUK_Definition) {
13449 AddAlignmentAttributesForRecord(RD);
13450 AddMsStructLayoutForRecord(RD);
13454 if (ModulePrivateLoc.isValid()) {
13455 if (isExplicitSpecialization)
13456 Diag(New->getLocation(), diag::err_module_private_specialization)
13458 << FixItHint::CreateRemoval(ModulePrivateLoc);
13459 // __module_private__ does not apply to local classes. However, we only
13460 // diagnose this as an error when the declaration specifiers are
13461 // freestanding. Here, we just ignore the __module_private__.
13462 else if (!SearchDC->isFunctionOrMethod())
13463 New->setModulePrivate();
13466 // If this is a specialization of a member class (of a class template),
13467 // check the specialization.
13468 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous))
13471 // If we're declaring or defining a tag in function prototype scope in C,
13472 // note that this type can only be used within the function and add it to
13473 // the list of decls to inject into the function definition scope.
13474 if ((Name || Kind == TTK_Enum) &&
13475 getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
13476 if (getLangOpts().CPlusPlus) {
13477 // C++ [dcl.fct]p6:
13478 // Types shall not be defined in return or parameter types.
13479 if (TUK == TUK_Definition && !IsTypeSpecifier) {
13480 Diag(Loc, diag::err_type_defined_in_param_type)
13484 } else if (!PrevDecl) {
13485 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
13490 New->setInvalidDecl();
13493 ProcessDeclAttributeList(S, New, Attr);
13495 // Set the lexical context. If the tag has a C++ scope specifier, the
13496 // lexical context will be different from the semantic context.
13497 New->setLexicalDeclContext(CurContext);
13499 // Mark this as a friend decl if applicable.
13500 // In Microsoft mode, a friend declaration also acts as a forward
13501 // declaration so we always pass true to setObjectOfFriendDecl to make
13502 // the tag name visible.
13503 if (TUK == TUK_Friend)
13504 New->setObjectOfFriendDecl(getLangOpts().MSVCCompat);
13506 // Set the access specifier.
13507 if (!Invalid && SearchDC->isRecord())
13508 SetMemberAccessSpecifier(New, PrevDecl, AS);
13510 if (TUK == TUK_Definition)
13511 New->startDefinition();
13513 // If this has an identifier, add it to the scope stack.
13514 if (TUK == TUK_Friend) {
13515 // We might be replacing an existing declaration in the lookup tables;
13516 // if so, borrow its access specifier.
13518 New->setAccess(PrevDecl->getAccess());
13520 DeclContext *DC = New->getDeclContext()->getRedeclContext();
13521 DC->makeDeclVisibleInContext(New);
13522 if (Name) // can be null along some error paths
13523 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
13524 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false);
13526 S = getNonFieldDeclScope(S);
13527 PushOnScopeChains(New, S, !IsForwardReference);
13528 if (IsForwardReference)
13529 SearchDC->makeDeclVisibleInContext(New);
13531 CurContext->addDecl(New);
13534 // If this is the C FILE type, notify the AST context.
13535 if (IdentifierInfo *II = New->getIdentifier())
13536 if (!New->isInvalidDecl() &&
13537 New->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
13539 Context.setFILEDecl(New);
13542 mergeDeclAttributes(New, PrevDecl);
13544 // If there's a #pragma GCC visibility in scope, set the visibility of this
13546 AddPushedVisibilityAttribute(New);
13549 // In C++, don't return an invalid declaration. We can't recover well from
13550 // the cases where we make the type anonymous.
13551 if (Invalid && getLangOpts().CPlusPlus) {
13552 if (New->isBeingDefined())
13553 if (auto RD = dyn_cast<RecordDecl>(New))
13554 RD->completeDefinition();
13561 void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) {
13562 AdjustDeclIfTemplate(TagD);
13563 TagDecl *Tag = cast<TagDecl>(TagD);
13565 // Enter the tag context.
13566 PushDeclContext(S, Tag);
13568 ActOnDocumentableDecl(TagD);
13570 // If there's a #pragma GCC visibility in scope, set the visibility of this
13572 AddPushedVisibilityAttribute(Tag);
13575 Decl *Sema::ActOnObjCContainerStartDefinition(Decl *IDecl) {
13576 assert(isa<ObjCContainerDecl>(IDecl) &&
13577 "ActOnObjCContainerStartDefinition - Not ObjCContainerDecl");
13578 DeclContext *OCD = cast<DeclContext>(IDecl);
13579 assert(getContainingDC(OCD) == CurContext &&
13580 "The next DeclContext should be lexically contained in the current one.");
13585 void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD,
13586 SourceLocation FinalLoc,
13587 bool IsFinalSpelledSealed,
13588 SourceLocation LBraceLoc) {
13589 AdjustDeclIfTemplate(TagD);
13590 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD);
13592 FieldCollector->StartClass();
13594 if (!Record->getIdentifier())
13597 if (FinalLoc.isValid())
13598 Record->addAttr(new (Context)
13599 FinalAttr(FinalLoc, Context, IsFinalSpelledSealed));
13602 // [...] The class-name is also inserted into the scope of the
13603 // class itself; this is known as the injected-class-name. For
13604 // purposes of access checking, the injected-class-name is treated
13605 // as if it were a public member name.
13606 CXXRecordDecl *InjectedClassName
13607 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext,
13608 Record->getLocStart(), Record->getLocation(),
13609 Record->getIdentifier(),
13610 /*PrevDecl=*/nullptr,
13611 /*DelayTypeCreation=*/true);
13612 Context.getTypeDeclType(InjectedClassName, Record);
13613 InjectedClassName->setImplicit();
13614 InjectedClassName->setAccess(AS_public);
13615 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate())
13616 InjectedClassName->setDescribedClassTemplate(Template);
13617 PushOnScopeChains(InjectedClassName, S);
13618 assert(InjectedClassName->isInjectedClassName() &&
13619 "Broken injected-class-name");
13622 void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD,
13623 SourceRange BraceRange) {
13624 AdjustDeclIfTemplate(TagD);
13625 TagDecl *Tag = cast<TagDecl>(TagD);
13626 Tag->setBraceRange(BraceRange);
13628 // Make sure we "complete" the definition even it is invalid.
13629 if (Tag->isBeingDefined()) {
13630 assert(Tag->isInvalidDecl() && "We should already have completed it");
13631 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
13632 RD->completeDefinition();
13635 if (isa<CXXRecordDecl>(Tag))
13636 FieldCollector->FinishClass();
13638 // Exit this scope of this tag's definition.
13641 if (getCurLexicalContext()->isObjCContainer() &&
13642 Tag->getDeclContext()->isFileContext())
13643 Tag->setTopLevelDeclInObjCContainer();
13645 // Notify the consumer that we've defined a tag.
13646 if (!Tag->isInvalidDecl())
13647 Consumer.HandleTagDeclDefinition(Tag);
13650 void Sema::ActOnObjCContainerFinishDefinition() {
13651 // Exit this scope of this interface definition.
13655 void Sema::ActOnObjCTemporaryExitContainerContext(DeclContext *DC) {
13656 assert(DC == CurContext && "Mismatch of container contexts");
13657 OriginalLexicalContext = DC;
13658 ActOnObjCContainerFinishDefinition();
13661 void Sema::ActOnObjCReenterContainerContext(DeclContext *DC) {
13662 ActOnObjCContainerStartDefinition(cast<Decl>(DC));
13663 OriginalLexicalContext = nullptr;
13666 void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) {
13667 AdjustDeclIfTemplate(TagD);
13668 TagDecl *Tag = cast<TagDecl>(TagD);
13669 Tag->setInvalidDecl();
13671 // Make sure we "complete" the definition even it is invalid.
13672 if (Tag->isBeingDefined()) {
13673 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
13674 RD->completeDefinition();
13677 // We're undoing ActOnTagStartDefinition here, not
13678 // ActOnStartCXXMemberDeclarations, so we don't have to mess with
13679 // the FieldCollector.
13684 // Note that FieldName may be null for anonymous bitfields.
13685 ExprResult Sema::VerifyBitField(SourceLocation FieldLoc,
13686 IdentifierInfo *FieldName,
13687 QualType FieldTy, bool IsMsStruct,
13688 Expr *BitWidth, bool *ZeroWidth) {
13689 // Default to true; that shouldn't confuse checks for emptiness
13693 // C99 6.7.2.1p4 - verify the field type.
13694 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
13695 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) {
13696 // Handle incomplete types with specific error.
13697 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete))
13698 return ExprError();
13700 return Diag(FieldLoc, diag::err_not_integral_type_bitfield)
13701 << FieldName << FieldTy << BitWidth->getSourceRange();
13702 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield)
13703 << FieldTy << BitWidth->getSourceRange();
13704 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth),
13705 UPPC_BitFieldWidth))
13706 return ExprError();
13708 // If the bit-width is type- or value-dependent, don't try to check
13710 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent())
13713 llvm::APSInt Value;
13714 ExprResult ICE = VerifyIntegerConstantExpression(BitWidth, &Value);
13715 if (ICE.isInvalid())
13717 BitWidth = ICE.get();
13719 if (Value != 0 && ZeroWidth)
13720 *ZeroWidth = false;
13722 // Zero-width bitfield is ok for anonymous field.
13723 if (Value == 0 && FieldName)
13724 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName;
13726 if (Value.isSigned() && Value.isNegative()) {
13728 return Diag(FieldLoc, diag::err_bitfield_has_negative_width)
13729 << FieldName << Value.toString(10);
13730 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width)
13731 << Value.toString(10);
13734 if (!FieldTy->isDependentType()) {
13735 uint64_t TypeStorageSize = Context.getTypeSize(FieldTy);
13736 uint64_t TypeWidth = Context.getIntWidth(FieldTy);
13737 bool BitfieldIsOverwide = Value.ugt(TypeWidth);
13739 // Over-wide bitfields are an error in C or when using the MSVC bitfield
13741 bool CStdConstraintViolation =
13742 BitfieldIsOverwide && !getLangOpts().CPlusPlus;
13743 bool MSBitfieldViolation =
13744 Value.ugt(TypeStorageSize) &&
13745 (IsMsStruct || Context.getTargetInfo().getCXXABI().isMicrosoft());
13746 if (CStdConstraintViolation || MSBitfieldViolation) {
13747 unsigned DiagWidth =
13748 CStdConstraintViolation ? TypeWidth : TypeStorageSize;
13750 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_width)
13751 << FieldName << (unsigned)Value.getZExtValue()
13752 << !CStdConstraintViolation << DiagWidth;
13754 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_width)
13755 << (unsigned)Value.getZExtValue() << !CStdConstraintViolation
13759 // Warn on types where the user might conceivably expect to get all
13760 // specified bits as value bits: that's all integral types other than
13762 if (BitfieldIsOverwide && !FieldTy->isBooleanType()) {
13764 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_width)
13765 << FieldName << (unsigned)Value.getZExtValue()
13766 << (unsigned)TypeWidth;
13768 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_width)
13769 << (unsigned)Value.getZExtValue() << (unsigned)TypeWidth;
13776 /// ActOnField - Each field of a C struct/union is passed into this in order
13777 /// to create a FieldDecl object for it.
13778 Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
13779 Declarator &D, Expr *BitfieldWidth) {
13780 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD),
13781 DeclStart, D, static_cast<Expr*>(BitfieldWidth),
13782 /*InitStyle=*/ICIS_NoInit, AS_public);
13786 /// HandleField - Analyze a field of a C struct or a C++ data member.
13788 FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
13789 SourceLocation DeclStart,
13790 Declarator &D, Expr *BitWidth,
13791 InClassInitStyle InitStyle,
13792 AccessSpecifier AS) {
13793 if (D.isDecompositionDeclarator()) {
13794 const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
13795 Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
13796 << Decomp.getSourceRange();
13800 IdentifierInfo *II = D.getIdentifier();
13801 SourceLocation Loc = DeclStart;
13802 if (II) Loc = D.getIdentifierLoc();
13804 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13805 QualType T = TInfo->getType();
13806 if (getLangOpts().CPlusPlus) {
13807 CheckExtraCXXDefaultArguments(D);
13809 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
13810 UPPC_DataMemberType)) {
13811 D.setInvalidType();
13813 TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
13817 // TR 18037 does not allow fields to be declared with address spaces.
13818 if (T.getQualifiers().hasAddressSpace()) {
13819 Diag(Loc, diag::err_field_with_address_space);
13820 D.setInvalidType();
13823 // OpenCL v1.2 s6.9b,r & OpenCL v2.0 s6.12.5 - The following types cannot be
13824 // used as structure or union field: image, sampler, event or block types.
13825 if (LangOpts.OpenCL && (T->isEventT() || T->isImageType() ||
13826 T->isSamplerT() || T->isBlockPointerType())) {
13827 Diag(Loc, diag::err_opencl_type_struct_or_union_field) << T;
13828 D.setInvalidType();
13831 DiagnoseFunctionSpecifiers(D.getDeclSpec());
13833 if (D.getDeclSpec().isInlineSpecified())
13834 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
13835 << getLangOpts().CPlusPlus1z;
13836 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
13837 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
13838 diag::err_invalid_thread)
13839 << DeclSpec::getSpecifierName(TSCS);
13841 // Check to see if this name was declared as a member previously
13842 NamedDecl *PrevDecl = nullptr;
13843 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
13844 LookupName(Previous, S);
13845 switch (Previous.getResultKind()) {
13846 case LookupResult::Found:
13847 case LookupResult::FoundUnresolvedValue:
13848 PrevDecl = Previous.getAsSingle<NamedDecl>();
13851 case LookupResult::FoundOverloaded:
13852 PrevDecl = Previous.getRepresentativeDecl();
13855 case LookupResult::NotFound:
13856 case LookupResult::NotFoundInCurrentInstantiation:
13857 case LookupResult::Ambiguous:
13860 Previous.suppressDiagnostics();
13862 if (PrevDecl && PrevDecl->isTemplateParameter()) {
13863 // Maybe we will complain about the shadowed template parameter.
13864 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
13865 // Just pretend that we didn't see the previous declaration.
13866 PrevDecl = nullptr;
13869 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
13870 PrevDecl = nullptr;
13873 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable);
13874 SourceLocation TSSL = D.getLocStart();
13876 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, InitStyle,
13877 TSSL, AS, PrevDecl, &D);
13879 if (NewFD->isInvalidDecl())
13880 Record->setInvalidDecl();
13882 if (D.getDeclSpec().isModulePrivateSpecified())
13883 NewFD->setModulePrivate();
13885 if (NewFD->isInvalidDecl() && PrevDecl) {
13886 // Don't introduce NewFD into scope; there's already something
13887 // with the same name in the same scope.
13889 PushOnScopeChains(NewFD, S);
13891 Record->addDecl(NewFD);
13896 /// \brief Build a new FieldDecl and check its well-formedness.
13898 /// This routine builds a new FieldDecl given the fields name, type,
13899 /// record, etc. \p PrevDecl should refer to any previous declaration
13900 /// with the same name and in the same scope as the field to be
13903 /// \returns a new FieldDecl.
13905 /// \todo The Declarator argument is a hack. It will be removed once
13906 FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T,
13907 TypeSourceInfo *TInfo,
13908 RecordDecl *Record, SourceLocation Loc,
13909 bool Mutable, Expr *BitWidth,
13910 InClassInitStyle InitStyle,
13911 SourceLocation TSSL,
13912 AccessSpecifier AS, NamedDecl *PrevDecl,
13914 IdentifierInfo *II = Name.getAsIdentifierInfo();
13915 bool InvalidDecl = false;
13916 if (D) InvalidDecl = D->isInvalidType();
13918 // If we receive a broken type, recover by assuming 'int' and
13919 // marking this declaration as invalid.
13921 InvalidDecl = true;
13925 QualType EltTy = Context.getBaseElementType(T);
13926 if (!EltTy->isDependentType()) {
13927 if (RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) {
13928 // Fields of incomplete type force their record to be invalid.
13929 Record->setInvalidDecl();
13930 InvalidDecl = true;
13933 EltTy->isIncompleteType(&Def);
13934 if (Def && Def->isInvalidDecl()) {
13935 Record->setInvalidDecl();
13936 InvalidDecl = true;
13941 // OpenCL v1.2 s6.9.c: bitfields are not supported.
13942 if (BitWidth && getLangOpts().OpenCL) {
13943 Diag(Loc, diag::err_opencl_bitfields);
13944 InvalidDecl = true;
13947 // C99 6.7.2.1p8: A member of a structure or union may have any type other
13948 // than a variably modified type.
13949 if (!InvalidDecl && T->isVariablyModifiedType()) {
13950 bool SizeIsNegative;
13951 llvm::APSInt Oversized;
13953 TypeSourceInfo *FixedTInfo =
13954 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
13958 Diag(Loc, diag::warn_illegal_constant_array_size);
13959 TInfo = FixedTInfo;
13960 T = FixedTInfo->getType();
13962 if (SizeIsNegative)
13963 Diag(Loc, diag::err_typecheck_negative_array_size);
13964 else if (Oversized.getBoolValue())
13965 Diag(Loc, diag::err_array_too_large)
13966 << Oversized.toString(10);
13968 Diag(Loc, diag::err_typecheck_field_variable_size);
13969 InvalidDecl = true;
13973 // Fields can not have abstract class types
13974 if (!InvalidDecl && RequireNonAbstractType(Loc, T,
13975 diag::err_abstract_type_in_decl,
13976 AbstractFieldType))
13977 InvalidDecl = true;
13979 bool ZeroWidth = false;
13981 BitWidth = nullptr;
13982 // If this is declared as a bit-field, check the bit-field.
13984 BitWidth = VerifyBitField(Loc, II, T, Record->isMsStruct(Context), BitWidth,
13987 InvalidDecl = true;
13988 BitWidth = nullptr;
13993 // Check that 'mutable' is consistent with the type of the declaration.
13994 if (!InvalidDecl && Mutable) {
13995 unsigned DiagID = 0;
13996 if (T->isReferenceType())
13997 DiagID = getLangOpts().MSVCCompat ? diag::ext_mutable_reference
13998 : diag::err_mutable_reference;
13999 else if (T.isConstQualified())
14000 DiagID = diag::err_mutable_const;
14003 SourceLocation ErrLoc = Loc;
14004 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid())
14005 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc();
14006 Diag(ErrLoc, DiagID);
14007 if (DiagID != diag::ext_mutable_reference) {
14009 InvalidDecl = true;
14014 // C++11 [class.union]p8 (DR1460):
14015 // At most one variant member of a union may have a
14016 // brace-or-equal-initializer.
14017 if (InitStyle != ICIS_NoInit)
14018 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Record), Loc);
14020 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo,
14021 BitWidth, Mutable, InitStyle);
14023 NewFD->setInvalidDecl();
14025 if (PrevDecl && !isa<TagDecl>(PrevDecl)) {
14026 Diag(Loc, diag::err_duplicate_member) << II;
14027 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
14028 NewFD->setInvalidDecl();
14031 if (!InvalidDecl && getLangOpts().CPlusPlus) {
14032 if (Record->isUnion()) {
14033 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
14034 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl());
14035 if (RDecl->getDefinition()) {
14036 // C++ [class.union]p1: An object of a class with a non-trivial
14037 // constructor, a non-trivial copy constructor, a non-trivial
14038 // destructor, or a non-trivial copy assignment operator
14039 // cannot be a member of a union, nor can an array of such
14041 if (CheckNontrivialField(NewFD))
14042 NewFD->setInvalidDecl();
14046 // C++ [class.union]p1: If a union contains a member of reference type,
14047 // the program is ill-formed, except when compiling with MSVC extensions
14049 if (EltTy->isReferenceType()) {
14050 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
14051 diag::ext_union_member_of_reference_type :
14052 diag::err_union_member_of_reference_type)
14053 << NewFD->getDeclName() << EltTy;
14054 if (!getLangOpts().MicrosoftExt)
14055 NewFD->setInvalidDecl();
14060 // FIXME: We need to pass in the attributes given an AST
14061 // representation, not a parser representation.
14063 // FIXME: The current scope is almost... but not entirely... correct here.
14064 ProcessDeclAttributes(getCurScope(), NewFD, *D);
14066 if (NewFD->hasAttrs())
14067 CheckAlignasUnderalignment(NewFD);
14070 // In auto-retain/release, infer strong retension for fields of
14071 // retainable type.
14072 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewFD))
14073 NewFD->setInvalidDecl();
14075 if (T.isObjCGCWeak())
14076 Diag(Loc, diag::warn_attribute_weak_on_field);
14078 NewFD->setAccess(AS);
14082 bool Sema::CheckNontrivialField(FieldDecl *FD) {
14084 assert(getLangOpts().CPlusPlus && "valid check only for C++");
14086 if (FD->isInvalidDecl() || FD->getType()->isDependentType())
14089 QualType EltTy = Context.getBaseElementType(FD->getType());
14090 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
14091 CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl());
14092 if (RDecl->getDefinition()) {
14093 // We check for copy constructors before constructors
14094 // because otherwise we'll never get complaints about
14095 // copy constructors.
14097 CXXSpecialMember member = CXXInvalid;
14098 // We're required to check for any non-trivial constructors. Since the
14099 // implicit default constructor is suppressed if there are any
14100 // user-declared constructors, we just need to check that there is a
14101 // trivial default constructor and a trivial copy constructor. (We don't
14102 // worry about move constructors here, since this is a C++98 check.)
14103 if (RDecl->hasNonTrivialCopyConstructor())
14104 member = CXXCopyConstructor;
14105 else if (!RDecl->hasTrivialDefaultConstructor())
14106 member = CXXDefaultConstructor;
14107 else if (RDecl->hasNonTrivialCopyAssignment())
14108 member = CXXCopyAssignment;
14109 else if (RDecl->hasNonTrivialDestructor())
14110 member = CXXDestructor;
14112 if (member != CXXInvalid) {
14113 if (!getLangOpts().CPlusPlus11 &&
14114 getLangOpts().ObjCAutoRefCount && RDecl->hasObjectMember()) {
14115 // Objective-C++ ARC: it is an error to have a non-trivial field of
14116 // a union. However, system headers in Objective-C programs
14117 // occasionally have Objective-C lifetime objects within unions,
14118 // and rather than cause the program to fail, we make those
14119 // members unavailable.
14120 SourceLocation Loc = FD->getLocation();
14121 if (getSourceManager().isInSystemHeader(Loc)) {
14122 if (!FD->hasAttr<UnavailableAttr>())
14123 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
14124 UnavailableAttr::IR_ARCFieldWithOwnership, Loc));
14129 Diag(FD->getLocation(), getLangOpts().CPlusPlus11 ?
14130 diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member :
14131 diag::err_illegal_union_or_anon_struct_member)
14132 << FD->getParent()->isUnion() << FD->getDeclName() << member;
14133 DiagnoseNontrivial(RDecl, member);
14134 return !getLangOpts().CPlusPlus11;
14142 /// TranslateIvarVisibility - Translate visibility from a token ID to an
14143 /// AST enum value.
14144 static ObjCIvarDecl::AccessControl
14145 TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) {
14146 switch (ivarVisibility) {
14147 default: llvm_unreachable("Unknown visitibility kind");
14148 case tok::objc_private: return ObjCIvarDecl::Private;
14149 case tok::objc_public: return ObjCIvarDecl::Public;
14150 case tok::objc_protected: return ObjCIvarDecl::Protected;
14151 case tok::objc_package: return ObjCIvarDecl::Package;
14155 /// ActOnIvar - Each ivar field of an objective-c class is passed into this
14156 /// in order to create an IvarDecl object for it.
14157 Decl *Sema::ActOnIvar(Scope *S,
14158 SourceLocation DeclStart,
14159 Declarator &D, Expr *BitfieldWidth,
14160 tok::ObjCKeywordKind Visibility) {
14162 IdentifierInfo *II = D.getIdentifier();
14163 Expr *BitWidth = (Expr*)BitfieldWidth;
14164 SourceLocation Loc = DeclStart;
14165 if (II) Loc = D.getIdentifierLoc();
14167 // FIXME: Unnamed fields can be handled in various different ways, for
14168 // example, unnamed unions inject all members into the struct namespace!
14170 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
14171 QualType T = TInfo->getType();
14174 // 6.7.2.1p3, 6.7.2.1p4
14175 BitWidth = VerifyBitField(Loc, II, T, /*IsMsStruct*/false, BitWidth).get();
14177 D.setInvalidType();
14184 if (T->isReferenceType()) {
14185 Diag(Loc, diag::err_ivar_reference_type);
14186 D.setInvalidType();
14188 // C99 6.7.2.1p8: A member of a structure or union may have any type other
14189 // than a variably modified type.
14190 else if (T->isVariablyModifiedType()) {
14191 Diag(Loc, diag::err_typecheck_ivar_variable_size);
14192 D.setInvalidType();
14195 // Get the visibility (access control) for this ivar.
14196 ObjCIvarDecl::AccessControl ac =
14197 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility)
14198 : ObjCIvarDecl::None;
14199 // Must set ivar's DeclContext to its enclosing interface.
14200 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(CurContext);
14201 if (!EnclosingDecl || EnclosingDecl->isInvalidDecl())
14203 ObjCContainerDecl *EnclosingContext;
14204 if (ObjCImplementationDecl *IMPDecl =
14205 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
14206 if (LangOpts.ObjCRuntime.isFragile()) {
14207 // Case of ivar declared in an implementation. Context is that of its class.
14208 EnclosingContext = IMPDecl->getClassInterface();
14209 assert(EnclosingContext && "Implementation has no class interface!");
14212 EnclosingContext = EnclosingDecl;
14214 if (ObjCCategoryDecl *CDecl =
14215 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
14216 if (LangOpts.ObjCRuntime.isFragile() || !CDecl->IsClassExtension()) {
14217 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension();
14221 EnclosingContext = EnclosingDecl;
14224 // Construct the decl.
14225 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext,
14226 DeclStart, Loc, II, T,
14227 TInfo, ac, (Expr *)BitfieldWidth);
14230 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName,
14232 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S)
14233 && !isa<TagDecl>(PrevDecl)) {
14234 Diag(Loc, diag::err_duplicate_member) << II;
14235 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
14236 NewID->setInvalidDecl();
14240 // Process attributes attached to the ivar.
14241 ProcessDeclAttributes(S, NewID, D);
14243 if (D.isInvalidType())
14244 NewID->setInvalidDecl();
14246 // In ARC, infer 'retaining' for ivars of retainable type.
14247 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewID))
14248 NewID->setInvalidDecl();
14250 if (D.getDeclSpec().isModulePrivateSpecified())
14251 NewID->setModulePrivate();
14254 // FIXME: When interfaces are DeclContexts, we'll need to add
14255 // these to the interface.
14257 IdResolver.AddDecl(NewID);
14260 if (LangOpts.ObjCRuntime.isNonFragile() &&
14261 !NewID->isInvalidDecl() && isa<ObjCInterfaceDecl>(EnclosingDecl))
14262 Diag(Loc, diag::warn_ivars_in_interface);
14267 /// ActOnLastBitfield - This routine handles synthesized bitfields rules for
14268 /// class and class extensions. For every class \@interface and class
14269 /// extension \@interface, if the last ivar is a bitfield of any type,
14270 /// then add an implicit `char :0` ivar to the end of that interface.
14271 void Sema::ActOnLastBitfield(SourceLocation DeclLoc,
14272 SmallVectorImpl<Decl *> &AllIvarDecls) {
14273 if (LangOpts.ObjCRuntime.isFragile() || AllIvarDecls.empty())
14276 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1];
14277 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl);
14279 if (!Ivar->isBitField() || Ivar->getBitWidthValue(Context) == 0)
14281 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CurContext);
14283 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(CurContext)) {
14284 if (!CD->IsClassExtension())
14287 // No need to add this to end of @implementation.
14291 // All conditions are met. Add a new bitfield to the tail end of ivars.
14292 llvm::APInt Zero(Context.getTypeSize(Context.IntTy), 0);
14293 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.IntTy, DeclLoc);
14295 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(CurContext),
14296 DeclLoc, DeclLoc, nullptr,
14298 Context.getTrivialTypeSourceInfo(Context.CharTy,
14300 ObjCIvarDecl::Private, BW,
14302 AllIvarDecls.push_back(Ivar);
14305 void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
14306 ArrayRef<Decl *> Fields, SourceLocation LBrac,
14307 SourceLocation RBrac, AttributeList *Attr) {
14308 assert(EnclosingDecl && "missing record or interface decl");
14310 // If this is an Objective-C @implementation or category and we have
14311 // new fields here we should reset the layout of the interface since
14312 // it will now change.
14313 if (!Fields.empty() && isa<ObjCContainerDecl>(EnclosingDecl)) {
14314 ObjCContainerDecl *DC = cast<ObjCContainerDecl>(EnclosingDecl);
14315 switch (DC->getKind()) {
14317 case Decl::ObjCCategory:
14318 Context.ResetObjCLayout(cast<ObjCCategoryDecl>(DC)->getClassInterface());
14320 case Decl::ObjCImplementation:
14322 ResetObjCLayout(cast<ObjCImplementationDecl>(DC)->getClassInterface());
14327 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl);
14329 // Start counting up the number of named members; make sure to include
14330 // members of anonymous structs and unions in the total.
14331 unsigned NumNamedMembers = 0;
14333 for (const auto *I : Record->decls()) {
14334 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
14335 if (IFD->getDeclName())
14340 // Verify that all the fields are okay.
14341 SmallVector<FieldDecl*, 32> RecFields;
14343 bool ARCErrReported = false;
14344 for (ArrayRef<Decl *>::iterator i = Fields.begin(), end = Fields.end();
14346 FieldDecl *FD = cast<FieldDecl>(*i);
14348 // Get the type for the field.
14349 const Type *FDTy = FD->getType().getTypePtr();
14351 if (!FD->isAnonymousStructOrUnion()) {
14352 // Remember all fields written by the user.
14353 RecFields.push_back(FD);
14356 // If the field is already invalid for some reason, don't emit more
14357 // diagnostics about it.
14358 if (FD->isInvalidDecl()) {
14359 EnclosingDecl->setInvalidDecl();
14364 // A structure or union shall not contain a member with
14365 // incomplete or function type (hence, a structure shall not
14366 // contain an instance of itself, but may contain a pointer to
14367 // an instance of itself), except that the last member of a
14368 // structure with more than one named member may have incomplete
14369 // array type; such a structure (and any union containing,
14370 // possibly recursively, a member that is such a structure)
14371 // shall not be a member of a structure or an element of an
14373 if (FDTy->isFunctionType()) {
14374 // Field declared as a function.
14375 Diag(FD->getLocation(), diag::err_field_declared_as_function)
14376 << FD->getDeclName();
14377 FD->setInvalidDecl();
14378 EnclosingDecl->setInvalidDecl();
14380 } else if (FDTy->isIncompleteArrayType() && Record &&
14381 ((i + 1 == Fields.end() && !Record->isUnion()) ||
14382 ((getLangOpts().MicrosoftExt ||
14383 getLangOpts().CPlusPlus) &&
14384 (i + 1 == Fields.end() || Record->isUnion())))) {
14385 // Flexible array member.
14386 // Microsoft and g++ is more permissive regarding flexible array.
14387 // It will accept flexible array in union and also
14388 // as the sole element of a struct/class.
14389 unsigned DiagID = 0;
14390 if (Record->isUnion())
14391 DiagID = getLangOpts().MicrosoftExt
14392 ? diag::ext_flexible_array_union_ms
14393 : getLangOpts().CPlusPlus
14394 ? diag::ext_flexible_array_union_gnu
14395 : diag::err_flexible_array_union;
14396 else if (NumNamedMembers < 1)
14397 DiagID = getLangOpts().MicrosoftExt
14398 ? diag::ext_flexible_array_empty_aggregate_ms
14399 : getLangOpts().CPlusPlus
14400 ? diag::ext_flexible_array_empty_aggregate_gnu
14401 : diag::err_flexible_array_empty_aggregate;
14404 Diag(FD->getLocation(), DiagID) << FD->getDeclName()
14405 << Record->getTagKind();
14406 // While the layout of types that contain virtual bases is not specified
14407 // by the C++ standard, both the Itanium and Microsoft C++ ABIs place
14408 // virtual bases after the derived members. This would make a flexible
14409 // array member declared at the end of an object not adjacent to the end
14411 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record))
14412 if (RD->getNumVBases() != 0)
14413 Diag(FD->getLocation(), diag::err_flexible_array_virtual_base)
14414 << FD->getDeclName() << Record->getTagKind();
14415 if (!getLangOpts().C99)
14416 Diag(FD->getLocation(), diag::ext_c99_flexible_array_member)
14417 << FD->getDeclName() << Record->getTagKind();
14419 // If the element type has a non-trivial destructor, we would not
14420 // implicitly destroy the elements, so disallow it for now.
14422 // FIXME: GCC allows this. We should probably either implicitly delete
14423 // the destructor of the containing class, or just allow this.
14424 QualType BaseElem = Context.getBaseElementType(FD->getType());
14425 if (!BaseElem->isDependentType() && BaseElem.isDestructedType()) {
14426 Diag(FD->getLocation(), diag::err_flexible_array_has_nontrivial_dtor)
14427 << FD->getDeclName() << FD->getType();
14428 FD->setInvalidDecl();
14429 EnclosingDecl->setInvalidDecl();
14432 // Okay, we have a legal flexible array member at the end of the struct.
14433 Record->setHasFlexibleArrayMember(true);
14434 } else if (!FDTy->isDependentType() &&
14435 RequireCompleteType(FD->getLocation(), FD->getType(),
14436 diag::err_field_incomplete)) {
14438 FD->setInvalidDecl();
14439 EnclosingDecl->setInvalidDecl();
14441 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) {
14442 if (Record && FDTTy->getDecl()->hasFlexibleArrayMember()) {
14443 // A type which contains a flexible array member is considered to be a
14444 // flexible array member.
14445 Record->setHasFlexibleArrayMember(true);
14446 if (!Record->isUnion()) {
14447 // If this is a struct/class and this is not the last element, reject
14448 // it. Note that GCC supports variable sized arrays in the middle of
14450 if (i + 1 != Fields.end())
14451 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct)
14452 << FD->getDeclName() << FD->getType();
14454 // We support flexible arrays at the end of structs in
14455 // other structs as an extension.
14456 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct)
14457 << FD->getDeclName();
14461 if (isa<ObjCContainerDecl>(EnclosingDecl) &&
14462 RequireNonAbstractType(FD->getLocation(), FD->getType(),
14463 diag::err_abstract_type_in_decl,
14464 AbstractIvarType)) {
14465 // Ivars can not have abstract class types
14466 FD->setInvalidDecl();
14468 if (Record && FDTTy->getDecl()->hasObjectMember())
14469 Record->setHasObjectMember(true);
14470 if (Record && FDTTy->getDecl()->hasVolatileMember())
14471 Record->setHasVolatileMember(true);
14472 } else if (FDTy->isObjCObjectType()) {
14473 /// A field cannot be an Objective-c object
14474 Diag(FD->getLocation(), diag::err_statically_allocated_object)
14475 << FixItHint::CreateInsertion(FD->getLocation(), "*");
14476 QualType T = Context.getObjCObjectPointerType(FD->getType());
14478 } else if (getLangOpts().ObjCAutoRefCount && Record && !ARCErrReported &&
14479 (!getLangOpts().CPlusPlus || Record->isUnion())) {
14480 // It's an error in ARC if a field has lifetime.
14481 // We don't want to report this in a system header, though,
14482 // so we just make the field unavailable.
14483 // FIXME: that's really not sufficient; we need to make the type
14484 // itself invalid to, say, initialize or copy.
14485 QualType T = FD->getType();
14486 Qualifiers::ObjCLifetime lifetime = T.getObjCLifetime();
14487 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone) {
14488 SourceLocation loc = FD->getLocation();
14489 if (getSourceManager().isInSystemHeader(loc)) {
14490 if (!FD->hasAttr<UnavailableAttr>()) {
14491 FD->addAttr(UnavailableAttr::CreateImplicit(Context, "",
14492 UnavailableAttr::IR_ARCFieldWithOwnership, loc));
14495 Diag(FD->getLocation(), diag::err_arc_objc_object_in_tag)
14496 << T->isBlockPointerType() << Record->getTagKind();
14498 ARCErrReported = true;
14500 } else if (getLangOpts().ObjC1 &&
14501 getLangOpts().getGC() != LangOptions::NonGC &&
14502 Record && !Record->hasObjectMember()) {
14503 if (FD->getType()->isObjCObjectPointerType() ||
14504 FD->getType().isObjCGCStrong())
14505 Record->setHasObjectMember(true);
14506 else if (Context.getAsArrayType(FD->getType())) {
14507 QualType BaseType = Context.getBaseElementType(FD->getType());
14508 if (BaseType->isRecordType() &&
14509 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember())
14510 Record->setHasObjectMember(true);
14511 else if (BaseType->isObjCObjectPointerType() ||
14512 BaseType.isObjCGCStrong())
14513 Record->setHasObjectMember(true);
14516 if (Record && FD->getType().isVolatileQualified())
14517 Record->setHasVolatileMember(true);
14518 // Keep track of the number of named members.
14519 if (FD->getIdentifier())
14523 // Okay, we successfully defined 'Record'.
14525 bool Completed = false;
14526 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
14527 if (!CXXRecord->isInvalidDecl()) {
14528 // Set access bits correctly on the directly-declared conversions.
14529 for (CXXRecordDecl::conversion_iterator
14530 I = CXXRecord->conversion_begin(),
14531 E = CXXRecord->conversion_end(); I != E; ++I)
14532 I.setAccess((*I)->getAccess());
14535 if (!CXXRecord->isDependentType()) {
14536 if (CXXRecord->hasUserDeclaredDestructor()) {
14537 // Adjust user-defined destructor exception spec.
14538 if (getLangOpts().CPlusPlus11)
14539 AdjustDestructorExceptionSpec(CXXRecord,
14540 CXXRecord->getDestructor());
14543 if (!CXXRecord->isInvalidDecl()) {
14544 // Add any implicitly-declared members to this class.
14545 AddImplicitlyDeclaredMembersToClass(CXXRecord);
14547 // If we have virtual base classes, we may end up finding multiple
14548 // final overriders for a given virtual function. Check for this
14550 if (CXXRecord->getNumVBases()) {
14551 CXXFinalOverriderMap FinalOverriders;
14552 CXXRecord->getFinalOverriders(FinalOverriders);
14554 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
14555 MEnd = FinalOverriders.end();
14557 for (OverridingMethods::iterator SO = M->second.begin(),
14558 SOEnd = M->second.end();
14559 SO != SOEnd; ++SO) {
14560 assert(SO->second.size() > 0 &&
14561 "Virtual function without overridding functions?");
14562 if (SO->second.size() == 1)
14565 // C++ [class.virtual]p2:
14566 // In a derived class, if a virtual member function of a base
14567 // class subobject has more than one final overrider the
14568 // program is ill-formed.
14569 Diag(Record->getLocation(), diag::err_multiple_final_overriders)
14570 << (const NamedDecl *)M->first << Record;
14571 Diag(M->first->getLocation(),
14572 diag::note_overridden_virtual_function);
14573 for (OverridingMethods::overriding_iterator
14574 OM = SO->second.begin(),
14575 OMEnd = SO->second.end();
14577 Diag(OM->Method->getLocation(), diag::note_final_overrider)
14578 << (const NamedDecl *)M->first << OM->Method->getParent();
14580 Record->setInvalidDecl();
14583 CXXRecord->completeDefinition(&FinalOverriders);
14591 Record->completeDefinition();
14593 // We may have deferred checking for a deleted destructor. Check now.
14594 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
14595 auto *Dtor = CXXRecord->getDestructor();
14596 if (Dtor && Dtor->isImplicit() &&
14597 ShouldDeleteSpecialMember(Dtor, CXXDestructor))
14598 SetDeclDeleted(Dtor, CXXRecord->getLocation());
14601 if (Record->hasAttrs()) {
14602 CheckAlignasUnderalignment(Record);
14604 if (const MSInheritanceAttr *IA = Record->getAttr<MSInheritanceAttr>())
14605 checkMSInheritanceAttrOnDefinition(cast<CXXRecordDecl>(Record),
14606 IA->getRange(), IA->getBestCase(),
14607 IA->getSemanticSpelling());
14610 // Check if the structure/union declaration is a type that can have zero
14611 // size in C. For C this is a language extension, for C++ it may cause
14612 // compatibility problems.
14613 bool CheckForZeroSize;
14614 if (!getLangOpts().CPlusPlus) {
14615 CheckForZeroSize = true;
14617 // For C++ filter out types that cannot be referenced in C code.
14618 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record);
14620 CXXRecord->getLexicalDeclContext()->isExternCContext() &&
14621 !CXXRecord->isDependentType() &&
14622 CXXRecord->isCLike();
14624 if (CheckForZeroSize) {
14625 bool ZeroSize = true;
14626 bool IsEmpty = true;
14627 unsigned NonBitFields = 0;
14628 for (RecordDecl::field_iterator I = Record->field_begin(),
14629 E = Record->field_end();
14630 (NonBitFields == 0 || ZeroSize) && I != E; ++I) {
14632 if (I->isUnnamedBitfield()) {
14633 if (I->getBitWidthValue(Context) > 0)
14637 QualType FieldType = I->getType();
14638 if (FieldType->isIncompleteType() ||
14639 !Context.getTypeSizeInChars(FieldType).isZero())
14644 // Empty structs are an extension in C (C99 6.7.2.1p7). They are
14645 // allowed in C++, but warn if its declaration is inside
14646 // extern "C" block.
14648 Diag(RecLoc, getLangOpts().CPlusPlus ?
14649 diag::warn_zero_size_struct_union_in_extern_c :
14650 diag::warn_zero_size_struct_union_compat)
14651 << IsEmpty << Record->isUnion() << (NonBitFields > 1);
14654 // Structs without named members are extension in C (C99 6.7.2.1p7),
14655 // but are accepted by GCC.
14656 if (NonBitFields == 0 && !getLangOpts().CPlusPlus) {
14657 Diag(RecLoc, IsEmpty ? diag::ext_empty_struct_union :
14658 diag::ext_no_named_members_in_struct_union)
14659 << Record->isUnion();
14663 ObjCIvarDecl **ClsFields =
14664 reinterpret_cast<ObjCIvarDecl**>(RecFields.data());
14665 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) {
14666 ID->setEndOfDefinitionLoc(RBrac);
14667 // Add ivar's to class's DeclContext.
14668 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
14669 ClsFields[i]->setLexicalDeclContext(ID);
14670 ID->addDecl(ClsFields[i]);
14672 // Must enforce the rule that ivars in the base classes may not be
14674 if (ID->getSuperClass())
14675 DiagnoseDuplicateIvars(ID, ID->getSuperClass());
14676 } else if (ObjCImplementationDecl *IMPDecl =
14677 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
14678 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl");
14679 for (unsigned I = 0, N = RecFields.size(); I != N; ++I)
14680 // Ivar declared in @implementation never belongs to the implementation.
14681 // Only it is in implementation's lexical context.
14682 ClsFields[I]->setLexicalDeclContext(IMPDecl);
14683 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac);
14684 IMPDecl->setIvarLBraceLoc(LBrac);
14685 IMPDecl->setIvarRBraceLoc(RBrac);
14686 } else if (ObjCCategoryDecl *CDecl =
14687 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
14688 // case of ivars in class extension; all other cases have been
14689 // reported as errors elsewhere.
14690 // FIXME. Class extension does not have a LocEnd field.
14691 // CDecl->setLocEnd(RBrac);
14692 // Add ivar's to class extension's DeclContext.
14693 // Diagnose redeclaration of private ivars.
14694 ObjCInterfaceDecl *IDecl = CDecl->getClassInterface();
14695 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
14697 if (const ObjCIvarDecl *ClsIvar =
14698 IDecl->getIvarDecl(ClsFields[i]->getIdentifier())) {
14699 Diag(ClsFields[i]->getLocation(),
14700 diag::err_duplicate_ivar_declaration);
14701 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
14704 for (const auto *Ext : IDecl->known_extensions()) {
14705 if (const ObjCIvarDecl *ClsExtIvar
14706 = Ext->getIvarDecl(ClsFields[i]->getIdentifier())) {
14707 Diag(ClsFields[i]->getLocation(),
14708 diag::err_duplicate_ivar_declaration);
14709 Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
14714 ClsFields[i]->setLexicalDeclContext(CDecl);
14715 CDecl->addDecl(ClsFields[i]);
14717 CDecl->setIvarLBraceLoc(LBrac);
14718 CDecl->setIvarRBraceLoc(RBrac);
14723 ProcessDeclAttributeList(S, Record, Attr);
14726 /// \brief Determine whether the given integral value is representable within
14727 /// the given type T.
14728 static bool isRepresentableIntegerValue(ASTContext &Context,
14729 llvm::APSInt &Value,
14731 assert(T->isIntegralType(Context) && "Integral type required!");
14732 unsigned BitWidth = Context.getIntWidth(T);
14734 if (Value.isUnsigned() || Value.isNonNegative()) {
14735 if (T->isSignedIntegerOrEnumerationType())
14737 return Value.getActiveBits() <= BitWidth;
14739 return Value.getMinSignedBits() <= BitWidth;
14742 // \brief Given an integral type, return the next larger integral type
14743 // (or a NULL type of no such type exists).
14744 static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) {
14745 // FIXME: Int128/UInt128 support, which also needs to be introduced into
14746 // enum checking below.
14747 assert(T->isIntegralType(Context) && "Integral type required!");
14748 const unsigned NumTypes = 4;
14749 QualType SignedIntegralTypes[NumTypes] = {
14750 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy
14752 QualType UnsignedIntegralTypes[NumTypes] = {
14753 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy,
14754 Context.UnsignedLongLongTy
14757 unsigned BitWidth = Context.getTypeSize(T);
14758 QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes
14759 : UnsignedIntegralTypes;
14760 for (unsigned I = 0; I != NumTypes; ++I)
14761 if (Context.getTypeSize(Types[I]) > BitWidth)
14767 EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum,
14768 EnumConstantDecl *LastEnumConst,
14769 SourceLocation IdLoc,
14770 IdentifierInfo *Id,
14772 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
14773 llvm::APSInt EnumVal(IntWidth);
14776 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue))
14780 Val = DefaultLvalueConversion(Val).get();
14783 if (Enum->isDependentType() || Val->isTypeDependent())
14784 EltTy = Context.DependentTy;
14786 SourceLocation ExpLoc;
14787 if (getLangOpts().CPlusPlus11 && Enum->isFixed() &&
14788 !getLangOpts().MSVCCompat) {
14789 // C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the
14790 // constant-expression in the enumerator-definition shall be a converted
14791 // constant expression of the underlying type.
14792 EltTy = Enum->getIntegerType();
14793 ExprResult Converted =
14794 CheckConvertedConstantExpression(Val, EltTy, EnumVal,
14796 if (Converted.isInvalid())
14799 Val = Converted.get();
14800 } else if (!Val->isValueDependent() &&
14801 !(Val = VerifyIntegerConstantExpression(Val,
14802 &EnumVal).get())) {
14803 // C99 6.7.2.2p2: Make sure we have an integer constant expression.
14805 if (Enum->isFixed()) {
14806 EltTy = Enum->getIntegerType();
14808 // In Obj-C and Microsoft mode, require the enumeration value to be
14809 // representable in the underlying type of the enumeration. In C++11,
14810 // we perform a non-narrowing conversion as part of converted constant
14811 // expression checking.
14812 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
14813 if (getLangOpts().MSVCCompat) {
14814 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy;
14815 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
14817 Diag(IdLoc, diag::err_enumerator_too_large) << EltTy;
14819 Val = ImpCastExprToType(Val, EltTy,
14820 EltTy->isBooleanType() ?
14821 CK_IntegralToBoolean : CK_IntegralCast)
14823 } else if (getLangOpts().CPlusPlus) {
14824 // C++11 [dcl.enum]p5:
14825 // If the underlying type is not fixed, the type of each enumerator
14826 // is the type of its initializing value:
14827 // - If an initializer is specified for an enumerator, the
14828 // initializing value has the same type as the expression.
14829 EltTy = Val->getType();
14832 // The expression that defines the value of an enumeration constant
14833 // shall be an integer constant expression that has a value
14834 // representable as an int.
14836 // Complain if the value is not representable in an int.
14837 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy))
14838 Diag(IdLoc, diag::ext_enum_value_not_int)
14839 << EnumVal.toString(10) << Val->getSourceRange()
14840 << (EnumVal.isUnsigned() || EnumVal.isNonNegative());
14841 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) {
14842 // Force the type of the expression to 'int'.
14843 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).get();
14845 EltTy = Val->getType();
14852 if (Enum->isDependentType())
14853 EltTy = Context.DependentTy;
14854 else if (!LastEnumConst) {
14855 // C++0x [dcl.enum]p5:
14856 // If the underlying type is not fixed, the type of each enumerator
14857 // is the type of its initializing value:
14858 // - If no initializer is specified for the first enumerator, the
14859 // initializing value has an unspecified integral type.
14861 // GCC uses 'int' for its unspecified integral type, as does
14863 if (Enum->isFixed()) {
14864 EltTy = Enum->getIntegerType();
14867 EltTy = Context.IntTy;
14870 // Assign the last value + 1.
14871 EnumVal = LastEnumConst->getInitVal();
14873 EltTy = LastEnumConst->getType();
14875 // Check for overflow on increment.
14876 if (EnumVal < LastEnumConst->getInitVal()) {
14877 // C++0x [dcl.enum]p5:
14878 // If the underlying type is not fixed, the type of each enumerator
14879 // is the type of its initializing value:
14881 // - Otherwise the type of the initializing value is the same as
14882 // the type of the initializing value of the preceding enumerator
14883 // unless the incremented value is not representable in that type,
14884 // in which case the type is an unspecified integral type
14885 // sufficient to contain the incremented value. If no such type
14886 // exists, the program is ill-formed.
14887 QualType T = getNextLargerIntegralType(Context, EltTy);
14888 if (T.isNull() || Enum->isFixed()) {
14889 // There is no integral type larger enough to represent this
14890 // value. Complain, then allow the value to wrap around.
14891 EnumVal = LastEnumConst->getInitVal();
14892 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2);
14894 if (Enum->isFixed())
14895 // When the underlying type is fixed, this is ill-formed.
14896 Diag(IdLoc, diag::err_enumerator_wrapped)
14897 << EnumVal.toString(10)
14900 Diag(IdLoc, diag::ext_enumerator_increment_too_large)
14901 << EnumVal.toString(10);
14906 // Retrieve the last enumerator's value, extent that type to the
14907 // type that is supposed to be large enough to represent the incremented
14908 // value, then increment.
14909 EnumVal = LastEnumConst->getInitVal();
14910 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
14911 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy));
14914 // If we're not in C++, diagnose the overflow of enumerator values,
14915 // which in C99 means that the enumerator value is not representable in
14916 // an int (C99 6.7.2.2p2). However, we support GCC's extension that
14917 // permits enumerator values that are representable in some larger
14919 if (!getLangOpts().CPlusPlus && !T.isNull())
14920 Diag(IdLoc, diag::warn_enum_value_overflow);
14921 } else if (!getLangOpts().CPlusPlus &&
14922 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
14923 // Enforce C99 6.7.2.2p2 even when we compute the next value.
14924 Diag(IdLoc, diag::ext_enum_value_not_int)
14925 << EnumVal.toString(10) << 1;
14930 if (!EltTy->isDependentType()) {
14931 // Make the enumerator value match the signedness and size of the
14932 // enumerator's type.
14933 EnumVal = EnumVal.extOrTrunc(Context.getIntWidth(EltTy));
14934 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
14937 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy,
14941 Sema::SkipBodyInfo Sema::shouldSkipAnonEnumBody(Scope *S, IdentifierInfo *II,
14942 SourceLocation IILoc) {
14943 if (!(getLangOpts().Modules || getLangOpts().ModulesLocalVisibility) ||
14944 !getLangOpts().CPlusPlus)
14945 return SkipBodyInfo();
14947 // We have an anonymous enum definition. Look up the first enumerator to
14948 // determine if we should merge the definition with an existing one and
14950 NamedDecl *PrevDecl = LookupSingleName(S, II, IILoc, LookupOrdinaryName,
14952 auto *PrevECD = dyn_cast_or_null<EnumConstantDecl>(PrevDecl);
14954 return SkipBodyInfo();
14956 EnumDecl *PrevED = cast<EnumDecl>(PrevECD->getDeclContext());
14958 if (!PrevED->getDeclName() && !hasVisibleDefinition(PrevED, &Hidden)) {
14960 Skip.Previous = Hidden;
14964 return SkipBodyInfo();
14967 Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst,
14968 SourceLocation IdLoc, IdentifierInfo *Id,
14969 AttributeList *Attr,
14970 SourceLocation EqualLoc, Expr *Val) {
14971 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl);
14972 EnumConstantDecl *LastEnumConst =
14973 cast_or_null<EnumConstantDecl>(lastEnumConst);
14975 // The scope passed in may not be a decl scope. Zip up the scope tree until
14976 // we find one that is.
14977 S = getNonFieldDeclScope(S);
14979 // Verify that there isn't already something declared with this name in this
14981 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName,
14983 if (PrevDecl && PrevDecl->isTemplateParameter()) {
14984 // Maybe we will complain about the shadowed template parameter.
14985 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl);
14986 // Just pretend that we didn't see the previous declaration.
14987 PrevDecl = nullptr;
14990 // C++ [class.mem]p15:
14991 // If T is the name of a class, then each of the following shall have a name
14992 // different from T:
14993 // - every enumerator of every member of class T that is an unscoped
14995 if (!TheEnumDecl->isScoped())
14996 DiagnoseClassNameShadow(TheEnumDecl->getDeclContext(),
14997 DeclarationNameInfo(Id, IdLoc));
14999 EnumConstantDecl *New =
15000 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val);
15005 // When in C++, we may get a TagDecl with the same name; in this case the
15006 // enum constant will 'hide' the tag.
15007 assert((getLangOpts().CPlusPlus || !isa<TagDecl>(PrevDecl)) &&
15008 "Received TagDecl when not in C++!");
15009 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S) &&
15010 shouldLinkPossiblyHiddenDecl(PrevDecl, New)) {
15011 if (isa<EnumConstantDecl>(PrevDecl))
15012 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id;
15014 Diag(IdLoc, diag::err_redefinition) << Id;
15015 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
15020 // Process attributes.
15021 if (Attr) ProcessDeclAttributeList(S, New, Attr);
15023 // Register this decl in the current scope stack.
15024 New->setAccess(TheEnumDecl->getAccess());
15025 PushOnScopeChains(New, S);
15027 ActOnDocumentableDecl(New);
15032 // Returns true when the enum initial expression does not trigger the
15033 // duplicate enum warning. A few common cases are exempted as follows:
15034 // Element2 = Element1
15035 // Element2 = Element1 + 1
15036 // Element2 = Element1 - 1
15037 // Where Element2 and Element1 are from the same enum.
15038 static bool ValidDuplicateEnum(EnumConstantDecl *ECD, EnumDecl *Enum) {
15039 Expr *InitExpr = ECD->getInitExpr();
15042 InitExpr = InitExpr->IgnoreImpCasts();
15044 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(InitExpr)) {
15045 if (!BO->isAdditiveOp())
15047 IntegerLiteral *IL = dyn_cast<IntegerLiteral>(BO->getRHS());
15050 if (IL->getValue() != 1)
15053 InitExpr = BO->getLHS();
15056 // This checks if the elements are from the same enum.
15057 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InitExpr);
15061 EnumConstantDecl *EnumConstant = dyn_cast<EnumConstantDecl>(DRE->getDecl());
15065 if (cast<EnumDecl>(TagDecl::castFromDeclContext(ECD->getDeclContext())) !=
15075 bool isTombstoneOrEmptyKey;
15076 DupKey(int64_t val, bool isTombstoneOrEmptyKey)
15077 : val(val), isTombstoneOrEmptyKey(isTombstoneOrEmptyKey) {}
15080 static DupKey GetDupKey(const llvm::APSInt& Val) {
15081 return DupKey(Val.isSigned() ? Val.getSExtValue() : Val.getZExtValue(),
15085 struct DenseMapInfoDupKey {
15086 static DupKey getEmptyKey() { return DupKey(0, true); }
15087 static DupKey getTombstoneKey() { return DupKey(1, true); }
15088 static unsigned getHashValue(const DupKey Key) {
15089 return (unsigned)(Key.val * 37);
15091 static bool isEqual(const DupKey& LHS, const DupKey& RHS) {
15092 return LHS.isTombstoneOrEmptyKey == RHS.isTombstoneOrEmptyKey &&
15093 LHS.val == RHS.val;
15096 } // end anonymous namespace
15098 // Emits a warning when an element is implicitly set a value that
15099 // a previous element has already been set to.
15100 static void CheckForDuplicateEnumValues(Sema &S, ArrayRef<Decl *> Elements,
15102 QualType EnumType) {
15103 if (S.Diags.isIgnored(diag::warn_duplicate_enum_values, Enum->getLocation()))
15105 // Avoid anonymous enums
15106 if (!Enum->getIdentifier())
15109 // Only check for small enums.
15110 if (Enum->getNumPositiveBits() > 63 || Enum->getNumNegativeBits() > 64)
15113 typedef SmallVector<EnumConstantDecl *, 3> ECDVector;
15114 typedef SmallVector<ECDVector *, 3> DuplicatesVector;
15116 typedef llvm::PointerUnion<EnumConstantDecl*, ECDVector*> DeclOrVector;
15117 typedef llvm::DenseMap<DupKey, DeclOrVector, DenseMapInfoDupKey>
15120 DuplicatesVector DupVector;
15121 ValueToVectorMap EnumMap;
15123 // Populate the EnumMap with all values represented by enum constants without
15125 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15126 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]);
15128 // Null EnumConstantDecl means a previous diagnostic has been emitted for
15129 // this constant. Skip this enum since it may be ill-formed.
15134 if (ECD->getInitExpr())
15137 DupKey Key = GetDupKey(ECD->getInitVal());
15138 DeclOrVector &Entry = EnumMap[Key];
15140 // First time encountering this value.
15141 if (Entry.isNull())
15145 // Create vectors for any values that has duplicates.
15146 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15147 EnumConstantDecl *ECD = cast<EnumConstantDecl>(Elements[i]);
15148 if (!ValidDuplicateEnum(ECD, Enum))
15151 DupKey Key = GetDupKey(ECD->getInitVal());
15153 DeclOrVector& Entry = EnumMap[Key];
15154 if (Entry.isNull())
15157 if (EnumConstantDecl *D = Entry.dyn_cast<EnumConstantDecl*>()) {
15158 // Ensure constants are different.
15162 // Create new vector and push values onto it.
15163 ECDVector *Vec = new ECDVector();
15165 Vec->push_back(ECD);
15167 // Update entry to point to the duplicates vector.
15170 // Store the vector somewhere we can consult later for quick emission of
15172 DupVector.push_back(Vec);
15176 ECDVector *Vec = Entry.get<ECDVector*>();
15177 // Make sure constants are not added more than once.
15178 if (*Vec->begin() == ECD)
15181 Vec->push_back(ECD);
15184 // Emit diagnostics.
15185 for (DuplicatesVector::iterator DupVectorIter = DupVector.begin(),
15186 DupVectorEnd = DupVector.end();
15187 DupVectorIter != DupVectorEnd; ++DupVectorIter) {
15188 ECDVector *Vec = *DupVectorIter;
15189 assert(Vec->size() > 1 && "ECDVector should have at least 2 elements.");
15191 // Emit warning for one enum constant.
15192 ECDVector::iterator I = Vec->begin();
15193 S.Diag((*I)->getLocation(), diag::warn_duplicate_enum_values)
15194 << (*I)->getName() << (*I)->getInitVal().toString(10)
15195 << (*I)->getSourceRange();
15198 // Emit one note for each of the remaining enum constants with
15200 for (ECDVector::iterator E = Vec->end(); I != E; ++I)
15201 S.Diag((*I)->getLocation(), diag::note_duplicate_element)
15202 << (*I)->getName() << (*I)->getInitVal().toString(10)
15203 << (*I)->getSourceRange();
15208 bool Sema::IsValueInFlagEnum(const EnumDecl *ED, const llvm::APInt &Val,
15209 bool AllowMask) const {
15210 assert(ED->hasAttr<FlagEnumAttr>() && "looking for value in non-flag enum");
15211 assert(ED->isCompleteDefinition() && "expected enum definition");
15213 auto R = FlagBitsCache.insert(std::make_pair(ED, llvm::APInt()));
15214 llvm::APInt &FlagBits = R.first->second;
15217 for (auto *E : ED->enumerators()) {
15218 const auto &EVal = E->getInitVal();
15219 // Only single-bit enumerators introduce new flag values.
15220 if (EVal.isPowerOf2())
15221 FlagBits = FlagBits.zextOrSelf(EVal.getBitWidth()) | EVal;
15225 // A value is in a flag enum if either its bits are a subset of the enum's
15226 // flag bits (the first condition) or we are allowing masks and the same is
15227 // true of its complement (the second condition). When masks are allowed, we
15228 // allow the common idiom of ~(enum1 | enum2) to be a valid enum value.
15230 // While it's true that any value could be used as a mask, the assumption is
15231 // that a mask will have all of the insignificant bits set. Anything else is
15232 // likely a logic error.
15233 llvm::APInt FlagMask = ~FlagBits.zextOrTrunc(Val.getBitWidth());
15234 return !(FlagMask & Val) || (AllowMask && !(FlagMask & ~Val));
15237 void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceRange BraceRange,
15239 ArrayRef<Decl *> Elements,
15240 Scope *S, AttributeList *Attr) {
15241 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX);
15242 QualType EnumType = Context.getTypeDeclType(Enum);
15245 ProcessDeclAttributeList(S, Enum, Attr);
15247 if (Enum->isDependentType()) {
15248 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15249 EnumConstantDecl *ECD =
15250 cast_or_null<EnumConstantDecl>(Elements[i]);
15251 if (!ECD) continue;
15253 ECD->setType(EnumType);
15256 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0);
15260 // TODO: If the result value doesn't fit in an int, it must be a long or long
15261 // long value. ISO C does not support this, but GCC does as an extension,
15263 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
15264 unsigned CharWidth = Context.getTargetInfo().getCharWidth();
15265 unsigned ShortWidth = Context.getTargetInfo().getShortWidth();
15267 // Verify that all the values are okay, compute the size of the values, and
15268 // reverse the list.
15269 unsigned NumNegativeBits = 0;
15270 unsigned NumPositiveBits = 0;
15272 // Keep track of whether all elements have type int.
15273 bool AllElementsInt = true;
15275 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
15276 EnumConstantDecl *ECD =
15277 cast_or_null<EnumConstantDecl>(Elements[i]);
15278 if (!ECD) continue; // Already issued a diagnostic.
15280 const llvm::APSInt &InitVal = ECD->getInitVal();
15282 // Keep track of the size of positive and negative values.
15283 if (InitVal.isUnsigned() || InitVal.isNonNegative())
15284 NumPositiveBits = std::max(NumPositiveBits,
15285 (unsigned)InitVal.getActiveBits());
15287 NumNegativeBits = std::max(NumNegativeBits,
15288 (unsigned)InitVal.getMinSignedBits());
15290 // Keep track of whether every enum element has type int (very commmon).
15291 if (AllElementsInt)
15292 AllElementsInt = ECD->getType() == Context.IntTy;
15295 // Figure out the type that should be used for this enum.
15297 unsigned BestWidth;
15299 // C++0x N3000 [conv.prom]p3:
15300 // An rvalue of an unscoped enumeration type whose underlying
15301 // type is not fixed can be converted to an rvalue of the first
15302 // of the following types that can represent all the values of
15303 // the enumeration: int, unsigned int, long int, unsigned long
15304 // int, long long int, or unsigned long long int.
15306 // An identifier declared as an enumeration constant has type int.
15307 // The C99 rule is modified by a gcc extension
15308 QualType BestPromotionType;
15310 bool Packed = Enum->hasAttr<PackedAttr>();
15311 // -fshort-enums is the equivalent to specifying the packed attribute on all
15312 // enum definitions.
15313 if (LangOpts.ShortEnums)
15316 if (Enum->isFixed()) {
15317 BestType = Enum->getIntegerType();
15318 if (BestType->isPromotableIntegerType())
15319 BestPromotionType = Context.getPromotedIntegerType(BestType);
15321 BestPromotionType = BestType;
15323 BestWidth = Context.getIntWidth(BestType);
15325 else if (NumNegativeBits) {
15326 // If there is a negative value, figure out the smallest integer type (of
15327 // int/long/longlong) that fits.
15328 // If it's packed, check also if it fits a char or a short.
15329 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
15330 BestType = Context.SignedCharTy;
15331 BestWidth = CharWidth;
15332 } else if (Packed && NumNegativeBits <= ShortWidth &&
15333 NumPositiveBits < ShortWidth) {
15334 BestType = Context.ShortTy;
15335 BestWidth = ShortWidth;
15336 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
15337 BestType = Context.IntTy;
15338 BestWidth = IntWidth;
15340 BestWidth = Context.getTargetInfo().getLongWidth();
15342 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) {
15343 BestType = Context.LongTy;
15345 BestWidth = Context.getTargetInfo().getLongLongWidth();
15347 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth)
15348 Diag(Enum->getLocation(), diag::ext_enum_too_large);
15349 BestType = Context.LongLongTy;
15352 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType);
15354 // If there is no negative value, figure out the smallest type that fits
15355 // all of the enumerator values.
15356 // If it's packed, check also if it fits a char or a short.
15357 if (Packed && NumPositiveBits <= CharWidth) {
15358 BestType = Context.UnsignedCharTy;
15359 BestPromotionType = Context.IntTy;
15360 BestWidth = CharWidth;
15361 } else if (Packed && NumPositiveBits <= ShortWidth) {
15362 BestType = Context.UnsignedShortTy;
15363 BestPromotionType = Context.IntTy;
15364 BestWidth = ShortWidth;
15365 } else if (NumPositiveBits <= IntWidth) {
15366 BestType = Context.UnsignedIntTy;
15367 BestWidth = IntWidth;
15369 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
15370 ? Context.UnsignedIntTy : Context.IntTy;
15371 } else if (NumPositiveBits <=
15372 (BestWidth = Context.getTargetInfo().getLongWidth())) {
15373 BestType = Context.UnsignedLongTy;
15375 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
15376 ? Context.UnsignedLongTy : Context.LongTy;
15378 BestWidth = Context.getTargetInfo().getLongLongWidth();
15379 assert(NumPositiveBits <= BestWidth &&
15380 "How could an initializer get larger than ULL?");
15381 BestType = Context.UnsignedLongLongTy;
15383 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
15384 ? Context.UnsignedLongLongTy : Context.LongLongTy;
15388 // Loop over all of the enumerator constants, changing their types to match
15389 // the type of the enum if needed.
15390 for (auto *D : Elements) {
15391 auto *ECD = cast_or_null<EnumConstantDecl>(D);
15392 if (!ECD) continue; // Already issued a diagnostic.
15394 // Standard C says the enumerators have int type, but we allow, as an
15395 // extension, the enumerators to be larger than int size. If each
15396 // enumerator value fits in an int, type it as an int, otherwise type it the
15397 // same as the enumerator decl itself. This means that in "enum { X = 1U }"
15398 // that X has type 'int', not 'unsigned'.
15400 // Determine whether the value fits into an int.
15401 llvm::APSInt InitVal = ECD->getInitVal();
15403 // If it fits into an integer type, force it. Otherwise force it to match
15404 // the enum decl type.
15408 if (!getLangOpts().CPlusPlus &&
15409 !Enum->isFixed() &&
15410 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) {
15411 NewTy = Context.IntTy;
15412 NewWidth = IntWidth;
15414 } else if (ECD->getType() == BestType) {
15415 // Already the right type!
15416 if (getLangOpts().CPlusPlus)
15417 // C++ [dcl.enum]p4: Following the closing brace of an
15418 // enum-specifier, each enumerator has the type of its
15420 ECD->setType(EnumType);
15424 NewWidth = BestWidth;
15425 NewSign = BestType->isSignedIntegerOrEnumerationType();
15428 // Adjust the APSInt value.
15429 InitVal = InitVal.extOrTrunc(NewWidth);
15430 InitVal.setIsSigned(NewSign);
15431 ECD->setInitVal(InitVal);
15433 // Adjust the Expr initializer and type.
15434 if (ECD->getInitExpr() &&
15435 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType()))
15436 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy,
15438 ECD->getInitExpr(),
15439 /*base paths*/ nullptr,
15441 if (getLangOpts().CPlusPlus)
15442 // C++ [dcl.enum]p4: Following the closing brace of an
15443 // enum-specifier, each enumerator has the type of its
15445 ECD->setType(EnumType);
15447 ECD->setType(NewTy);
15450 Enum->completeDefinition(BestType, BestPromotionType,
15451 NumPositiveBits, NumNegativeBits);
15453 CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType);
15455 if (Enum->hasAttr<FlagEnumAttr>()) {
15456 for (Decl *D : Elements) {
15457 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(D);
15458 if (!ECD) continue; // Already issued a diagnostic.
15460 llvm::APSInt InitVal = ECD->getInitVal();
15461 if (InitVal != 0 && !InitVal.isPowerOf2() &&
15462 !IsValueInFlagEnum(Enum, InitVal, true))
15463 Diag(ECD->getLocation(), diag::warn_flag_enum_constant_out_of_range)
15468 // Now that the enum type is defined, ensure it's not been underaligned.
15469 if (Enum->hasAttrs())
15470 CheckAlignasUnderalignment(Enum);
15473 Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr,
15474 SourceLocation StartLoc,
15475 SourceLocation EndLoc) {
15476 StringLiteral *AsmString = cast<StringLiteral>(expr);
15478 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext,
15479 AsmString, StartLoc,
15481 CurContext->addDecl(New);
15485 static void checkModuleImportContext(Sema &S, Module *M,
15486 SourceLocation ImportLoc, DeclContext *DC,
15487 bool FromInclude = false) {
15488 SourceLocation ExternCLoc;
15490 if (auto *LSD = dyn_cast<LinkageSpecDecl>(DC)) {
15491 switch (LSD->getLanguage()) {
15492 case LinkageSpecDecl::lang_c:
15493 if (ExternCLoc.isInvalid())
15494 ExternCLoc = LSD->getLocStart();
15496 case LinkageSpecDecl::lang_cxx:
15499 DC = LSD->getParent();
15502 while (isa<LinkageSpecDecl>(DC))
15503 DC = DC->getParent();
15505 if (!isa<TranslationUnitDecl>(DC)) {
15506 S.Diag(ImportLoc, (FromInclude && S.isModuleVisible(M))
15507 ? diag::ext_module_import_not_at_top_level_noop
15508 : diag::err_module_import_not_at_top_level_fatal)
15509 << M->getFullModuleName() << DC;
15510 S.Diag(cast<Decl>(DC)->getLocStart(),
15511 diag::note_module_import_not_at_top_level) << DC;
15512 } else if (!M->IsExternC && ExternCLoc.isValid()) {
15513 S.Diag(ImportLoc, diag::ext_module_import_in_extern_c)
15514 << M->getFullModuleName();
15515 S.Diag(ExternCLoc, diag::note_extern_c_begins_here);
15519 Sema::DeclGroupPtrTy Sema::ActOnModuleDecl(SourceLocation ModuleLoc,
15520 ModuleDeclKind MDK,
15521 ModuleIdPath Path) {
15522 // 'module implementation' requires that we are not compiling a module of any
15523 // kind. 'module' and 'module partition' require that we are compiling a
15524 // module inteface (not a module map).
15525 auto CMK = getLangOpts().getCompilingModule();
15526 if (MDK == ModuleDeclKind::Implementation
15527 ? CMK != LangOptions::CMK_None
15528 : CMK != LangOptions::CMK_ModuleInterface) {
15529 Diag(ModuleLoc, diag::err_module_interface_implementation_mismatch)
15534 // FIXME: Create a ModuleDecl and return it.
15536 // FIXME: Most of this work should be done by the preprocessor rather than
15537 // here, in case we look ahead across something where the current
15538 // module matters (eg a #include).
15540 // The dots in a module name in the Modules TS are a lie. Unlike Clang's
15541 // hierarchical module map modules, the dots here are just another character
15542 // that can appear in a module name. Flatten down to the actual module name.
15543 std::string ModuleName;
15544 for (auto &Piece : Path) {
15545 if (!ModuleName.empty())
15547 ModuleName += Piece.first->getName();
15550 // If a module name was explicitly specified on the command line, it must be
15552 if (!getLangOpts().CurrentModule.empty() &&
15553 getLangOpts().CurrentModule != ModuleName) {
15554 Diag(Path.front().second, diag::err_current_module_name_mismatch)
15555 << SourceRange(Path.front().second, Path.back().second)
15556 << getLangOpts().CurrentModule;
15559 const_cast<LangOptions&>(getLangOpts()).CurrentModule = ModuleName;
15561 auto &Map = PP.getHeaderSearchInfo().getModuleMap();
15564 case ModuleDeclKind::Module: {
15565 // FIXME: Check we're not in a submodule.
15567 // We can't have imported a definition of this module or parsed a module
15568 // map defining it already.
15569 if (auto *M = Map.findModule(ModuleName)) {
15570 Diag(Path[0].second, diag::err_module_redefinition) << ModuleName;
15571 if (M->DefinitionLoc.isValid())
15572 Diag(M->DefinitionLoc, diag::note_prev_module_definition);
15573 else if (const auto *FE = M->getASTFile())
15574 Diag(M->DefinitionLoc, diag::note_prev_module_definition_from_ast_file)
15579 // Create a Module for the module that we're defining.
15580 Module *Mod = Map.createModuleForInterfaceUnit(ModuleLoc, ModuleName);
15581 assert(Mod && "module creation should not fail");
15583 // Enter the semantic scope of the module.
15584 ActOnModuleBegin(ModuleLoc, Mod);
15588 case ModuleDeclKind::Partition:
15589 // FIXME: Check we are in a submodule of the named module.
15592 case ModuleDeclKind::Implementation:
15593 std::pair<IdentifierInfo *, SourceLocation> ModuleNameLoc(
15594 PP.getIdentifierInfo(ModuleName), Path[0].second);
15596 DeclResult Import = ActOnModuleImport(ModuleLoc, ModuleLoc, ModuleNameLoc);
15597 if (Import.isInvalid())
15599 return ConvertDeclToDeclGroup(Import.get());
15602 llvm_unreachable("unexpected module decl kind");
15605 DeclResult Sema::ActOnModuleImport(SourceLocation StartLoc,
15606 SourceLocation ImportLoc,
15607 ModuleIdPath Path) {
15609 getModuleLoader().loadModule(ImportLoc, Path, Module::AllVisible,
15610 /*IsIncludeDirective=*/false);
15614 VisibleModules.setVisible(Mod, ImportLoc);
15616 checkModuleImportContext(*this, Mod, ImportLoc, CurContext);
15618 // FIXME: we should support importing a submodule within a different submodule
15619 // of the same top-level module. Until we do, make it an error rather than
15620 // silently ignoring the import.
15621 // Import-from-implementation is valid in the Modules TS. FIXME: Should we
15622 // warn on a redundant import of the current module?
15623 if (Mod->getTopLevelModuleName() == getLangOpts().CurrentModule &&
15624 (getLangOpts().isCompilingModule() || !getLangOpts().ModulesTS))
15625 Diag(ImportLoc, getLangOpts().isCompilingModule()
15626 ? diag::err_module_self_import
15627 : diag::err_module_import_in_implementation)
15628 << Mod->getFullModuleName() << getLangOpts().CurrentModule;
15630 SmallVector<SourceLocation, 2> IdentifierLocs;
15631 Module *ModCheck = Mod;
15632 for (unsigned I = 0, N = Path.size(); I != N; ++I) {
15633 // If we've run out of module parents, just drop the remaining identifiers.
15634 // We need the length to be consistent.
15637 ModCheck = ModCheck->Parent;
15639 IdentifierLocs.push_back(Path[I].second);
15642 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15643 ImportDecl *Import = ImportDecl::Create(Context, TU, StartLoc,
15644 Mod, IdentifierLocs);
15645 if (!ModuleScopes.empty())
15646 Context.addModuleInitializer(ModuleScopes.back().Module, Import);
15647 TU->addDecl(Import);
15651 void Sema::ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
15652 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext, true);
15653 BuildModuleInclude(DirectiveLoc, Mod);
15656 void Sema::BuildModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
15657 // Determine whether we're in the #include buffer for a module. The #includes
15658 // in that buffer do not qualify as module imports; they're just an
15659 // implementation detail of us building the module.
15661 // FIXME: Should we even get ActOnModuleInclude calls for those?
15662 bool IsInModuleIncludes =
15663 TUKind == TU_Module &&
15664 getSourceManager().isWrittenInMainFile(DirectiveLoc);
15666 bool ShouldAddImport = !IsInModuleIncludes;
15668 // If this module import was due to an inclusion directive, create an
15669 // implicit import declaration to capture it in the AST.
15670 if (ShouldAddImport) {
15671 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15672 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
15675 if (!ModuleScopes.empty())
15676 Context.addModuleInitializer(ModuleScopes.back().Module, ImportD);
15677 TU->addDecl(ImportD);
15678 Consumer.HandleImplicitImportDecl(ImportD);
15681 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, DirectiveLoc);
15682 VisibleModules.setVisible(Mod, DirectiveLoc);
15685 void Sema::ActOnModuleBegin(SourceLocation DirectiveLoc, Module *Mod) {
15686 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext, true);
15688 ModuleScopes.push_back({});
15689 ModuleScopes.back().Module = Mod;
15690 if (getLangOpts().ModulesLocalVisibility)
15691 ModuleScopes.back().OuterVisibleModules = std::move(VisibleModules);
15693 VisibleModules.setVisible(Mod, DirectiveLoc);
15696 void Sema::ActOnModuleEnd(SourceLocation EofLoc, Module *Mod) {
15697 if (getLangOpts().ModulesLocalVisibility) {
15698 VisibleModules = std::move(ModuleScopes.back().OuterVisibleModules);
15699 // Leaving a module hides namespace names, so our visible namespace cache
15700 // is now out of date.
15701 VisibleNamespaceCache.clear();
15704 assert(!ModuleScopes.empty() && ModuleScopes.back().Module == Mod &&
15705 "left the wrong module scope");
15706 ModuleScopes.pop_back();
15708 // We got to the end of processing a #include of a local module. Create an
15709 // ImportDecl as we would for an imported module.
15710 FileID File = getSourceManager().getFileID(EofLoc);
15711 assert(File != getSourceManager().getMainFileID() &&
15712 "end of submodule in main source file");
15713 SourceLocation DirectiveLoc = getSourceManager().getIncludeLoc(File);
15714 BuildModuleInclude(DirectiveLoc, Mod);
15717 void Sema::createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
15719 // Bail if we're not allowed to implicitly import a module here.
15720 if (isSFINAEContext() || !getLangOpts().ModulesErrorRecovery)
15723 // Create the implicit import declaration.
15724 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
15725 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
15727 TU->addDecl(ImportD);
15728 Consumer.HandleImplicitImportDecl(ImportD);
15730 // Make the module visible.
15731 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, Loc);
15732 VisibleModules.setVisible(Mod, Loc);
15735 /// We have parsed the start of an export declaration, including the '{'
15737 Decl *Sema::ActOnStartExportDecl(Scope *S, SourceLocation ExportLoc,
15738 SourceLocation LBraceLoc) {
15739 ExportDecl *D = ExportDecl::Create(Context, CurContext, ExportLoc);
15741 // C++ Modules TS draft:
15742 // An export-declaration [...] shall not contain more than one
15745 // The intent here is that an export-declaration cannot appear within another
15746 // export-declaration.
15747 if (D->isExported())
15748 Diag(ExportLoc, diag::err_export_within_export);
15750 CurContext->addDecl(D);
15751 PushDeclContext(S, D);
15755 /// Complete the definition of an export declaration.
15756 Decl *Sema::ActOnFinishExportDecl(Scope *S, Decl *D, SourceLocation RBraceLoc) {
15757 auto *ED = cast<ExportDecl>(D);
15758 if (RBraceLoc.isValid())
15759 ED->setRBraceLoc(RBraceLoc);
15761 // FIXME: Diagnose export of internal-linkage declaration (including
15762 // anonymous namespace).
15768 void Sema::ActOnPragmaRedefineExtname(IdentifierInfo* Name,
15769 IdentifierInfo* AliasName,
15770 SourceLocation PragmaLoc,
15771 SourceLocation NameLoc,
15772 SourceLocation AliasNameLoc) {
15773 NamedDecl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc,
15774 LookupOrdinaryName);
15775 AsmLabelAttr *Attr =
15776 AsmLabelAttr::CreateImplicit(Context, AliasName->getName(), AliasNameLoc);
15778 // If a declaration that:
15779 // 1) declares a function or a variable
15780 // 2) has external linkage
15781 // already exists, add a label attribute to it.
15782 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
15783 if (isDeclExternC(PrevDecl))
15784 PrevDecl->addAttr(Attr);
15786 Diag(PrevDecl->getLocation(), diag::warn_redefine_extname_not_applied)
15787 << /*Variable*/(isa<FunctionDecl>(PrevDecl) ? 0 : 1) << PrevDecl;
15788 // Otherwise, add a label atttibute to ExtnameUndeclaredIdentifiers.
15790 (void)ExtnameUndeclaredIdentifiers.insert(std::make_pair(Name, Attr));
15793 void Sema::ActOnPragmaWeakID(IdentifierInfo* Name,
15794 SourceLocation PragmaLoc,
15795 SourceLocation NameLoc) {
15796 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName);
15799 PrevDecl->addAttr(WeakAttr::CreateImplicit(Context, PragmaLoc));
15801 (void)WeakUndeclaredIdentifiers.insert(
15802 std::pair<IdentifierInfo*,WeakInfo>
15803 (Name, WeakInfo((IdentifierInfo*)nullptr, NameLoc)));
15807 void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name,
15808 IdentifierInfo* AliasName,
15809 SourceLocation PragmaLoc,
15810 SourceLocation NameLoc,
15811 SourceLocation AliasNameLoc) {
15812 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc,
15813 LookupOrdinaryName);
15814 WeakInfo W = WeakInfo(Name, NameLoc);
15816 if (PrevDecl && (isa<FunctionDecl>(PrevDecl) || isa<VarDecl>(PrevDecl))) {
15817 if (!PrevDecl->hasAttr<AliasAttr>())
15818 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl))
15819 DeclApplyPragmaWeak(TUScope, ND, W);
15821 (void)WeakUndeclaredIdentifiers.insert(
15822 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W));
15826 Decl *Sema::getObjCDeclContext() const {
15827 return (dyn_cast_or_null<ObjCContainerDecl>(CurContext));