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 "clang/Sema/SemaInternal.h"
15 #include "TypeLocBuilder.h"
16 #include "clang/AST/ASTConsumer.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/ASTLambda.h"
19 #include "clang/AST/CXXInheritance.h"
20 #include "clang/AST/CharUnits.h"
21 #include "clang/AST/CommentDiagnostic.h"
22 #include "clang/AST/DeclCXX.h"
23 #include "clang/AST/DeclObjC.h"
24 #include "clang/AST/DeclTemplate.h"
25 #include "clang/AST/EvaluatedExprVisitor.h"
26 #include "clang/AST/ExprCXX.h"
27 #include "clang/AST/StmtCXX.h"
28 #include "clang/Basic/Builtins.h"
29 #include "clang/Basic/PartialDiagnostic.h"
30 #include "clang/Basic/SourceManager.h"
31 #include "clang/Basic/TargetInfo.h"
32 #include "clang/Lex/HeaderSearch.h" // TODO: Sema shouldn't depend on Lex
33 #include "clang/Lex/Lexer.h" // TODO: Extract static functions to fix layering.
34 #include "clang/Lex/ModuleLoader.h" // TODO: Sema shouldn't depend on Lex
35 #include "clang/Lex/Preprocessor.h" // Included for isCodeCompletionEnabled()
36 #include "clang/Parse/ParseDiagnostic.h"
37 #include "clang/Sema/CXXFieldCollector.h"
38 #include "clang/Sema/DeclSpec.h"
39 #include "clang/Sema/DelayedDiagnostic.h"
40 #include "clang/Sema/Initialization.h"
41 #include "clang/Sema/Lookup.h"
42 #include "clang/Sema/ParsedTemplate.h"
43 #include "clang/Sema/Scope.h"
44 #include "clang/Sema/ScopeInfo.h"
45 #include "clang/Sema/Template.h"
46 #include "llvm/ADT/SmallString.h"
47 #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;
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_wchar_t:
113 case tok::kw___underlying_type:
116 case tok::annot_typename:
117 case tok::kw_char16_t:
118 case tok::kw_char32_t:
120 case tok::annot_decltype:
121 case tok::kw_decltype:
122 return getLangOpts().CPlusPlus;
131 static ParsedType recoverFromTypeInKnownDependentBase(Sema &S,
132 const IdentifierInfo &II,
133 SourceLocation NameLoc) {
134 // Find the first parent class template context, if any.
135 // FIXME: Perform the lookup in all enclosing class templates.
136 const CXXRecordDecl *RD = nullptr;
137 for (DeclContext *DC = S.CurContext; DC; DC = DC->getParent()) {
138 RD = dyn_cast<CXXRecordDecl>(DC);
139 if (RD && RD->getDescribedClassTemplate())
145 // Look for type decls in dependent base classes that have known primary
147 bool FoundTypeDecl = false;
148 for (const auto &Base : RD->bases()) {
149 auto *TST = Base.getType()->getAs<TemplateSpecializationType>();
150 if (!TST || !TST->isDependentType())
152 auto *TD = TST->getTemplateName().getAsTemplateDecl();
155 auto *BasePrimaryTemplate =
156 dyn_cast_or_null<CXXRecordDecl>(TD->getTemplatedDecl());
157 if (!BasePrimaryTemplate)
159 // FIXME: Allow lookup into non-dependent bases of dependent bases, possibly
160 // by calling or integrating with the main LookupQualifiedName mechanism.
161 for (NamedDecl *ND : BasePrimaryTemplate->lookup(&II)) {
164 FoundTypeDecl = isa<TypeDecl>(ND);
172 // We found some types in dependent base classes. Recover as if the user
173 // wrote 'typename MyClass::II' instead of 'II'. We'll fully resolve the
174 // lookup during template instantiation.
175 S.Diag(NameLoc, diag::ext_found_via_dependent_bases_lookup) << &II;
177 ASTContext &Context = S.Context;
178 auto *NNS = NestedNameSpecifier::Create(Context, nullptr, false,
179 cast<Type>(Context.getRecordType(RD)));
180 QualType T = Context.getDependentNameType(ETK_Typename, NNS, &II);
183 SS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
185 TypeLocBuilder Builder;
186 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
187 DepTL.setNameLoc(NameLoc);
188 DepTL.setElaboratedKeywordLoc(SourceLocation());
189 DepTL.setQualifierLoc(SS.getWithLocInContext(Context));
190 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
193 /// \brief If the identifier refers to a type name within this scope,
194 /// return the declaration of that type.
196 /// This routine performs ordinary name lookup of the identifier II
197 /// within the given scope, with optional C++ scope specifier SS, to
198 /// determine whether the name refers to a type. If so, returns an
199 /// opaque pointer (actually a QualType) corresponding to that
200 /// type. Otherwise, returns NULL.
201 ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
202 Scope *S, CXXScopeSpec *SS,
203 bool isClassName, bool HasTrailingDot,
204 ParsedType ObjectTypePtr,
205 bool IsCtorOrDtorName,
206 bool WantNontrivialTypeSourceInfo,
207 IdentifierInfo **CorrectedII) {
208 // Determine where we will perform name lookup.
209 DeclContext *LookupCtx = nullptr;
211 QualType ObjectType = ObjectTypePtr.get();
212 if (ObjectType->isRecordType())
213 LookupCtx = computeDeclContext(ObjectType);
214 } else if (SS && SS->isNotEmpty()) {
215 LookupCtx = computeDeclContext(*SS, false);
218 if (isDependentScopeSpecifier(*SS)) {
220 // A qualified-id that refers to a type and in which the
221 // nested-name-specifier depends on a template-parameter (14.6.2)
222 // shall be prefixed by the keyword typename to indicate that the
223 // qualified-id denotes a type, forming an
224 // elaborated-type-specifier (7.1.5.3).
226 // We therefore do not perform any name lookup if the result would
227 // refer to a member of an unknown specialization.
228 if (!isClassName && !IsCtorOrDtorName)
231 // We know from the grammar that this name refers to a type,
232 // so build a dependent node to describe the type.
233 if (WantNontrivialTypeSourceInfo)
234 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get();
236 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context);
237 QualType T = CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc,
239 return ParsedType::make(T);
245 if (!LookupCtx->isDependentContext() &&
246 RequireCompleteDeclContext(*SS, LookupCtx))
250 // FIXME: LookupNestedNameSpecifierName isn't the right kind of
251 // lookup for class-names.
252 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName :
254 LookupResult Result(*this, &II, NameLoc, Kind);
256 // Perform "qualified" name lookup into the declaration context we
257 // computed, which is either the type of the base of a member access
258 // expression or the declaration context associated with a prior
259 // nested-name-specifier.
260 LookupQualifiedName(Result, LookupCtx);
262 if (ObjectTypePtr && Result.empty()) {
263 // C++ [basic.lookup.classref]p3:
264 // If the unqualified-id is ~type-name, the type-name is looked up
265 // in the context of the entire postfix-expression. If the type T of
266 // the object expression is of a class type C, the type-name is also
267 // looked up in the scope of class C. At least one of the lookups shall
268 // find a name that refers to (possibly cv-qualified) T.
269 LookupName(Result, S);
272 // Perform unqualified name lookup.
273 LookupName(Result, S);
275 // For unqualified lookup in a class template in MSVC mode, look into
276 // dependent base classes where the primary class template is known.
277 if (Result.empty() && getLangOpts().MSVCCompat && (!SS || SS->isEmpty())) {
278 if (ParsedType TypeInBase =
279 recoverFromTypeInKnownDependentBase(*this, II, NameLoc))
284 NamedDecl *IIDecl = nullptr;
285 switch (Result.getResultKind()) {
286 case LookupResult::NotFound:
287 case LookupResult::NotFoundInCurrentInstantiation:
289 TypoCorrection Correction = CorrectTypo(
290 Result.getLookupNameInfo(), Kind, S, SS,
291 llvm::make_unique<TypeNameValidatorCCC>(true, isClassName),
293 IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo();
295 bool MemberOfUnknownSpecialization;
296 UnqualifiedId TemplateName;
297 TemplateName.setIdentifier(NewII, NameLoc);
298 NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier();
299 CXXScopeSpec NewSS, *NewSSPtr = SS;
301 NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc));
304 if (Correction && (NNS || NewII != &II) &&
305 // Ignore a correction to a template type as the to-be-corrected
306 // identifier is not a template (typo correction for template names
307 // is handled elsewhere).
308 !(getLangOpts().CPlusPlus && NewSSPtr &&
309 isTemplateName(S, *NewSSPtr, false, TemplateName, ParsedType(),
310 false, Template, MemberOfUnknownSpecialization))) {
311 ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr,
312 isClassName, HasTrailingDot, ObjectTypePtr,
314 WantNontrivialTypeSourceInfo);
316 diagnoseTypo(Correction,
317 PDiag(diag::err_unknown_type_or_class_name_suggest)
318 << Result.getLookupName() << isClassName);
320 SS->MakeTrivial(Context, NNS, SourceRange(NameLoc));
321 *CorrectedII = NewII;
326 // If typo correction failed or was not performed, fall through
327 case LookupResult::FoundOverloaded:
328 case LookupResult::FoundUnresolvedValue:
329 Result.suppressDiagnostics();
332 case LookupResult::Ambiguous:
333 // Recover from type-hiding ambiguities by hiding the type. We'll
334 // do the lookup again when looking for an object, and we can
335 // diagnose the error then. If we don't do this, then the error
336 // about hiding the type will be immediately followed by an error
337 // that only makes sense if the identifier was treated like a type.
338 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) {
339 Result.suppressDiagnostics();
343 // Look to see if we have a type anywhere in the list of results.
344 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end();
345 Res != ResEnd; ++Res) {
346 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) {
348 (*Res)->getLocation().getRawEncoding() <
349 IIDecl->getLocation().getRawEncoding())
355 // None of the entities we found is a type, so there is no way
356 // to even assume that the result is a type. In this case, don't
357 // complain about the ambiguity. The parser will either try to
358 // perform this lookup again (e.g., as an object name), which
359 // will produce the ambiguity, or will complain that it expected
361 Result.suppressDiagnostics();
365 // We found a type within the ambiguous lookup; diagnose the
366 // ambiguity and then return that type. This might be the right
367 // answer, or it might not be, but it suppresses any attempt to
368 // perform the name lookup again.
371 case LookupResult::Found:
372 IIDecl = Result.getFoundDecl();
376 assert(IIDecl && "Didn't find decl");
379 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) {
380 DiagnoseUseOfDecl(IIDecl, NameLoc);
382 T = Context.getTypeDeclType(TD);
383 MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
385 // NOTE: avoid constructing an ElaboratedType(Loc) if this is a
386 // constructor or destructor name (in such a case, the scope specifier
387 // will be attached to the enclosing Expr or Decl node).
388 if (SS && SS->isNotEmpty() && !IsCtorOrDtorName) {
389 if (WantNontrivialTypeSourceInfo) {
390 // Construct a type with type-source information.
391 TypeLocBuilder Builder;
392 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
394 T = getElaboratedType(ETK_None, *SS, T);
395 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
396 ElabTL.setElaboratedKeywordLoc(SourceLocation());
397 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context));
398 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
400 T = getElaboratedType(ETK_None, *SS, T);
403 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) {
404 (void)DiagnoseUseOfDecl(IDecl, NameLoc);
406 T = Context.getObjCInterfaceType(IDecl);
410 // If it's not plausibly a type, suppress diagnostics.
411 Result.suppressDiagnostics();
414 return ParsedType::make(T);
417 // Builds a fake NNS for the given decl context.
418 static NestedNameSpecifier *
419 synthesizeCurrentNestedNameSpecifier(ASTContext &Context, DeclContext *DC) {
420 for (;; DC = DC->getLookupParent()) {
421 DC = DC->getPrimaryContext();
422 auto *ND = dyn_cast<NamespaceDecl>(DC);
423 if (ND && !ND->isInline() && !ND->isAnonymousNamespace())
424 return NestedNameSpecifier::Create(Context, nullptr, ND);
425 else if (auto *RD = dyn_cast<CXXRecordDecl>(DC))
426 return NestedNameSpecifier::Create(Context, nullptr, RD->isTemplateDecl(),
427 RD->getTypeForDecl());
428 else if (isa<TranslationUnitDecl>(DC))
429 return NestedNameSpecifier::GlobalSpecifier(Context);
431 llvm_unreachable("something isn't in TU scope?");
434 ParsedType Sema::ActOnDelayedDefaultTemplateArg(const IdentifierInfo &II,
435 SourceLocation NameLoc) {
436 // Accepting an undeclared identifier as a default argument for a template
437 // type parameter is a Microsoft extension.
438 Diag(NameLoc, diag::ext_ms_delayed_template_argument) << &II;
440 // Build a fake DependentNameType that will perform lookup into CurContext at
441 // instantiation time. The name specifier isn't dependent, so template
442 // instantiation won't transform it. It will retry the lookup, however.
443 NestedNameSpecifier *NNS =
444 synthesizeCurrentNestedNameSpecifier(Context, CurContext);
445 QualType T = Context.getDependentNameType(ETK_None, NNS, &II);
447 // Build type location information. We synthesized the qualifier, so we have
448 // to build a fake NestedNameSpecifierLoc.
449 NestedNameSpecifierLocBuilder NNSLocBuilder;
450 NNSLocBuilder.MakeTrivial(Context, NNS, SourceRange(NameLoc));
451 NestedNameSpecifierLoc QualifierLoc = NNSLocBuilder.getWithLocInContext(Context);
453 TypeLocBuilder Builder;
454 DependentNameTypeLoc DepTL = Builder.push<DependentNameTypeLoc>(T);
455 DepTL.setNameLoc(NameLoc);
456 DepTL.setElaboratedKeywordLoc(SourceLocation());
457 DepTL.setQualifierLoc(QualifierLoc);
458 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
461 /// isTagName() - This method is called *for error recovery purposes only*
462 /// to determine if the specified name is a valid tag name ("struct foo"). If
463 /// so, this returns the TST for the tag corresponding to it (TST_enum,
464 /// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose
465 /// cases in C where the user forgot to specify the tag.
466 DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) {
467 // Do a tag name lookup in this scope.
468 LookupResult R(*this, &II, SourceLocation(), LookupTagName);
469 LookupName(R, S, false);
470 R.suppressDiagnostics();
471 if (R.getResultKind() == LookupResult::Found)
472 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) {
473 switch (TD->getTagKind()) {
474 case TTK_Struct: return DeclSpec::TST_struct;
475 case TTK_Interface: return DeclSpec::TST_interface;
476 case TTK_Union: return DeclSpec::TST_union;
477 case TTK_Class: return DeclSpec::TST_class;
478 case TTK_Enum: return DeclSpec::TST_enum;
482 return DeclSpec::TST_unspecified;
485 /// isMicrosoftMissingTypename - In Microsoft mode, within class scope,
486 /// if a CXXScopeSpec's type is equal to the type of one of the base classes
487 /// then downgrade the missing typename error to a warning.
488 /// This is needed for MSVC compatibility; Example:
490 /// template<class T> class A {
492 /// typedef int TYPE;
494 /// template<class T> class B : public A<T> {
496 /// A<T>::TYPE a; // no typename required because A<T> is a base class.
499 bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) {
500 if (CurContext->isRecord()) {
501 if (SS->getScopeRep()->getKind() == NestedNameSpecifier::Super)
504 const Type *Ty = SS->getScopeRep()->getAsType();
506 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext);
507 for (const auto &Base : RD->bases())
508 if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base.getType()))
510 return S->isFunctionPrototypeScope();
512 return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope();
515 void Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II,
516 SourceLocation IILoc,
519 ParsedType &SuggestedType,
520 bool AllowClassTemplates) {
521 // We don't have anything to suggest (yet).
522 SuggestedType = ParsedType();
524 // There may have been a typo in the name of the type. Look up typo
525 // results, in case we have something that we can suggest.
526 if (TypoCorrection Corrected =
527 CorrectTypo(DeclarationNameInfo(II, IILoc), LookupOrdinaryName, S, SS,
528 llvm::make_unique<TypeNameValidatorCCC>(
529 false, false, AllowClassTemplates),
530 CTK_ErrorRecovery)) {
531 if (Corrected.isKeyword()) {
532 // We corrected to a keyword.
533 diagnoseTypo(Corrected, PDiag(diag::err_unknown_typename_suggest) << II);
534 II = Corrected.getCorrectionAsIdentifierInfo();
536 // We found a similarly-named type or interface; suggest that.
537 if (!SS || !SS->isSet()) {
538 diagnoseTypo(Corrected,
539 PDiag(diag::err_unknown_typename_suggest) << II);
540 } else if (DeclContext *DC = computeDeclContext(*SS, false)) {
541 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
542 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
543 II->getName().equals(CorrectedStr);
544 diagnoseTypo(Corrected,
545 PDiag(diag::err_unknown_nested_typename_suggest)
546 << II << DC << DroppedSpecifier << SS->getRange());
548 llvm_unreachable("could not have corrected a typo here");
552 if (Corrected.getCorrectionSpecifier())
553 tmpSS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
555 SuggestedType = getTypeName(*Corrected.getCorrectionAsIdentifierInfo(),
556 IILoc, S, tmpSS.isSet() ? &tmpSS : SS, false,
558 /*IsCtorOrDtorName=*/false,
559 /*NonTrivialTypeSourceInfo=*/true);
564 if (getLangOpts().CPlusPlus) {
565 // See if II is a class template that the user forgot to pass arguments to.
567 Name.setIdentifier(II, IILoc);
568 CXXScopeSpec EmptySS;
569 TemplateTy TemplateResult;
570 bool MemberOfUnknownSpecialization;
571 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false,
572 Name, ParsedType(), true, TemplateResult,
573 MemberOfUnknownSpecialization) == TNK_Type_template) {
574 TemplateName TplName = TemplateResult.get();
575 Diag(IILoc, diag::err_template_missing_args) << TplName;
576 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) {
577 Diag(TplDecl->getLocation(), diag::note_template_decl_here)
578 << TplDecl->getTemplateParameters()->getSourceRange();
584 // FIXME: Should we move the logic that tries to recover from a missing tag
585 // (struct, union, enum) from Parser::ParseImplicitInt here, instead?
587 if (!SS || (!SS->isSet() && !SS->isInvalid()))
588 Diag(IILoc, diag::err_unknown_typename) << II;
589 else if (DeclContext *DC = computeDeclContext(*SS, false))
590 Diag(IILoc, diag::err_typename_nested_not_found)
591 << II << DC << SS->getRange();
592 else if (isDependentScopeSpecifier(*SS)) {
593 unsigned DiagID = diag::err_typename_missing;
594 if (getLangOpts().MSVCCompat && isMicrosoftMissingTypename(SS, S))
595 DiagID = diag::ext_typename_missing;
597 Diag(SS->getRange().getBegin(), DiagID)
598 << SS->getScopeRep() << II->getName()
599 << SourceRange(SS->getRange().getBegin(), IILoc)
600 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename ");
601 SuggestedType = ActOnTypenameType(S, SourceLocation(),
602 *SS, *II, IILoc).get();
604 assert(SS && SS->isInvalid() &&
605 "Invalid scope specifier has already been diagnosed");
609 /// \brief Determine whether the given result set contains either a type name
611 static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) {
612 bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus &&
613 NextToken.is(tok::less);
615 for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) {
616 if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I))
619 if (CheckTemplate && isa<TemplateDecl>(*I))
626 static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result,
627 Scope *S, CXXScopeSpec &SS,
628 IdentifierInfo *&Name,
629 SourceLocation NameLoc) {
630 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName);
631 SemaRef.LookupParsedName(R, S, &SS);
632 if (TagDecl *Tag = R.getAsSingle<TagDecl>()) {
633 StringRef FixItTagName;
634 switch (Tag->getTagKind()) {
636 FixItTagName = "class ";
640 FixItTagName = "enum ";
644 FixItTagName = "struct ";
648 FixItTagName = "__interface ";
652 FixItTagName = "union ";
656 StringRef TagName = FixItTagName.drop_back();
657 SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag)
658 << Name << TagName << SemaRef.getLangOpts().CPlusPlus
659 << FixItHint::CreateInsertion(NameLoc, FixItTagName);
661 for (LookupResult::iterator I = Result.begin(), IEnd = Result.end();
663 SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type)
666 // Replace lookup results with just the tag decl.
667 Result.clear(Sema::LookupTagName);
668 SemaRef.LookupParsedName(Result, S, &SS);
675 /// Build a ParsedType for a simple-type-specifier with a nested-name-specifier.
676 static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS,
677 QualType T, SourceLocation NameLoc) {
678 ASTContext &Context = S.Context;
680 TypeLocBuilder Builder;
681 Builder.pushTypeSpec(T).setNameLoc(NameLoc);
683 T = S.getElaboratedType(ETK_None, SS, T);
684 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T);
685 ElabTL.setElaboratedKeywordLoc(SourceLocation());
686 ElabTL.setQualifierLoc(SS.getWithLocInContext(Context));
687 return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T));
690 Sema::NameClassification
691 Sema::ClassifyName(Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name,
692 SourceLocation NameLoc, const Token &NextToken,
693 bool IsAddressOfOperand,
694 std::unique_ptr<CorrectionCandidateCallback> CCC) {
695 DeclarationNameInfo NameInfo(Name, NameLoc);
696 ObjCMethodDecl *CurMethod = getCurMethodDecl();
698 if (NextToken.is(tok::coloncolon)) {
699 BuildCXXNestedNameSpecifier(S, *Name, NameLoc, NextToken.getLocation(),
700 QualType(), false, SS, nullptr, false);
703 LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName);
704 LookupParsedName(Result, S, &SS, !CurMethod);
706 // For unqualified lookup in a class template in MSVC mode, look into
707 // dependent base classes where the primary class template is known.
708 if (Result.empty() && SS.isEmpty() && getLangOpts().MSVCCompat) {
709 if (ParsedType TypeInBase =
710 recoverFromTypeInKnownDependentBase(*this, *Name, NameLoc))
714 // Perform lookup for Objective-C instance variables (including automatically
715 // synthesized instance variables), if we're in an Objective-C method.
716 // FIXME: This lookup really, really needs to be folded in to the normal
717 // unqualified lookup mechanism.
718 if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) {
719 ExprResult E = LookupInObjCMethod(Result, S, Name, true);
720 if (E.get() || E.isInvalid())
724 bool SecondTry = false;
725 bool IsFilteredTemplateName = false;
728 switch (Result.getResultKind()) {
729 case LookupResult::NotFound:
730 // If an unqualified-id is followed by a '(', then we have a function
732 if (!SS.isSet() && NextToken.is(tok::l_paren)) {
733 // In C++, this is an ADL-only call.
735 if (getLangOpts().CPlusPlus)
736 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true);
739 // If the expression that precedes the parenthesized argument list in a
740 // function call consists solely of an identifier, and if no
741 // declaration is visible for this identifier, the identifier is
742 // implicitly declared exactly as if, in the innermost block containing
743 // the function call, the declaration
745 // extern int identifier ();
749 // We also allow this in C99 as an extension.
750 if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) {
752 Result.resolveKind();
753 return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false);
757 // In C, we first see whether there is a tag type by the same name, in
758 // which case it's likely that the user just forget to write "enum",
759 // "struct", or "union".
760 if (!getLangOpts().CPlusPlus && !SecondTry &&
761 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
765 // Perform typo correction to determine if there is another name that is
766 // close to this name.
767 if (!SecondTry && CCC) {
769 if (TypoCorrection Corrected = CorrectTypo(Result.getLookupNameInfo(),
770 Result.getLookupKind(), S,
772 CTK_ErrorRecovery)) {
773 unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest;
774 unsigned QualifiedDiag = diag::err_no_member_suggest;
776 NamedDecl *FirstDecl = Corrected.getCorrectionDecl();
777 NamedDecl *UnderlyingFirstDecl
778 = FirstDecl? FirstDecl->getUnderlyingDecl() : nullptr;
779 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
780 UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) {
781 UnqualifiedDiag = diag::err_no_template_suggest;
782 QualifiedDiag = diag::err_no_member_template_suggest;
783 } else if (UnderlyingFirstDecl &&
784 (isa<TypeDecl>(UnderlyingFirstDecl) ||
785 isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) ||
786 isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) {
787 UnqualifiedDiag = diag::err_unknown_typename_suggest;
788 QualifiedDiag = diag::err_unknown_nested_typename_suggest;
792 diagnoseTypo(Corrected, PDiag(UnqualifiedDiag) << Name);
793 } else {// FIXME: is this even reachable? Test it.
794 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
795 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
796 Name->getName().equals(CorrectedStr);
797 diagnoseTypo(Corrected, PDiag(QualifiedDiag)
798 << Name << computeDeclContext(SS, false)
799 << DroppedSpecifier << SS.getRange());
802 // Update the name, so that the caller has the new name.
803 Name = Corrected.getCorrectionAsIdentifierInfo();
805 // Typo correction corrected to a keyword.
806 if (Corrected.isKeyword())
809 // Also update the LookupResult...
810 // FIXME: This should probably go away at some point
812 Result.setLookupName(Corrected.getCorrection());
814 Result.addDecl(FirstDecl);
816 // If we found an Objective-C instance variable, let
817 // LookupInObjCMethod build the appropriate expression to
818 // reference the ivar.
819 // FIXME: This is a gross hack.
820 if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) {
822 ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier()));
830 // We failed to correct; just fall through and let the parser deal with it.
831 Result.suppressDiagnostics();
832 return NameClassification::Unknown();
834 case LookupResult::NotFoundInCurrentInstantiation: {
835 // We performed name lookup into the current instantiation, and there were
836 // dependent bases, so we treat this result the same way as any other
837 // dependent nested-name-specifier.
840 // A name used in a template declaration or definition and that is
841 // dependent on a template-parameter is assumed not to name a type
842 // unless the applicable name lookup finds a type name or the name is
843 // qualified by the keyword typename.
845 // FIXME: If the next token is '<', we might want to ask the parser to
846 // perform some heroics to see if we actually have a
847 // template-argument-list, which would indicate a missing 'template'
849 return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(),
850 NameInfo, IsAddressOfOperand,
851 /*TemplateArgs=*/nullptr);
854 case LookupResult::Found:
855 case LookupResult::FoundOverloaded:
856 case LookupResult::FoundUnresolvedValue:
859 case LookupResult::Ambiguous:
860 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
861 hasAnyAcceptableTemplateNames(Result)) {
862 // C++ [temp.local]p3:
863 // A lookup that finds an injected-class-name (10.2) can result in an
864 // ambiguity in certain cases (for example, if it is found in more than
865 // one base class). If all of the injected-class-names that are found
866 // refer to specializations of the same class template, and if the name
867 // is followed by a template-argument-list, the reference refers to the
868 // class template itself and not a specialization thereof, and is not
871 // This filtering can make an ambiguous result into an unambiguous one,
872 // so try again after filtering out template names.
873 FilterAcceptableTemplateNames(Result);
874 if (!Result.isAmbiguous()) {
875 IsFilteredTemplateName = true;
880 // Diagnose the ambiguity and return an error.
881 return NameClassification::Error();
884 if (getLangOpts().CPlusPlus && NextToken.is(tok::less) &&
885 (IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) {
886 // C++ [temp.names]p3:
887 // After name lookup (3.4) finds that a name is a template-name or that
888 // an operator-function-id or a literal- operator-id refers to a set of
889 // overloaded functions any member of which is a function template if
890 // this is followed by a <, the < is always taken as the delimiter of a
891 // template-argument-list and never as the less-than operator.
892 if (!IsFilteredTemplateName)
893 FilterAcceptableTemplateNames(Result);
895 if (!Result.empty()) {
896 bool IsFunctionTemplate;
898 TemplateName Template;
899 if (Result.end() - Result.begin() > 1) {
900 IsFunctionTemplate = true;
901 Template = Context.getOverloadedTemplateName(Result.begin(),
905 = cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl());
906 IsFunctionTemplate = isa<FunctionTemplateDecl>(TD);
907 IsVarTemplate = isa<VarTemplateDecl>(TD);
909 if (SS.isSet() && !SS.isInvalid())
910 Template = Context.getQualifiedTemplateName(SS.getScopeRep(),
911 /*TemplateKeyword=*/false,
914 Template = TemplateName(TD);
917 if (IsFunctionTemplate) {
918 // Function templates always go through overload resolution, at which
919 // point we'll perform the various checks (e.g., accessibility) we need
920 // to based on which function we selected.
921 Result.suppressDiagnostics();
923 return NameClassification::FunctionTemplate(Template);
926 return IsVarTemplate ? NameClassification::VarTemplate(Template)
927 : NameClassification::TypeTemplate(Template);
931 NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl();
932 if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) {
933 DiagnoseUseOfDecl(Type, NameLoc);
934 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
935 QualType T = Context.getTypeDeclType(Type);
937 return buildNestedType(*this, SS, T, NameLoc);
938 return ParsedType::make(T);
941 ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl);
943 // FIXME: It's unfortunate that we don't have a Type node for handling this.
944 if (ObjCCompatibleAliasDecl *Alias =
945 dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl))
946 Class = Alias->getClassInterface();
950 DiagnoseUseOfDecl(Class, NameLoc);
952 if (NextToken.is(tok::period)) {
953 // Interface. <something> is parsed as a property reference expression.
954 // Just return "unknown" as a fall-through for now.
955 Result.suppressDiagnostics();
956 return NameClassification::Unknown();
959 QualType T = Context.getObjCInterfaceType(Class);
960 return ParsedType::make(T);
963 // We can have a type template here if we're classifying a template argument.
964 if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl))
965 return NameClassification::TypeTemplate(
966 TemplateName(cast<TemplateDecl>(FirstDecl)));
968 // Check for a tag type hidden by a non-type decl in a few cases where it
969 // seems likely a type is wanted instead of the non-type that was found.
970 bool NextIsOp = NextToken.is(tok::amp) || NextToken.is(tok::star);
971 if ((NextToken.is(tok::identifier) ||
973 FirstDecl->getUnderlyingDecl()->isFunctionOrFunctionTemplate())) &&
974 isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) {
975 TypeDecl *Type = Result.getAsSingle<TypeDecl>();
976 DiagnoseUseOfDecl(Type, NameLoc);
977 QualType T = Context.getTypeDeclType(Type);
979 return buildNestedType(*this, SS, T, NameLoc);
980 return ParsedType::make(T);
983 if (FirstDecl->isCXXClassMember())
984 return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result,
987 bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren));
988 return BuildDeclarationNameExpr(SS, Result, ADL);
991 // Determines the context to return to after temporarily entering a
992 // context. This depends in an unnecessarily complicated way on the
993 // exact ordering of callbacks from the parser.
994 DeclContext *Sema::getContainingDC(DeclContext *DC) {
996 // Functions defined inline within classes aren't parsed until we've
997 // finished parsing the top-level class, so the top-level class is
998 // the context we'll need to return to.
999 // A Lambda call operator whose parent is a class must not be treated
1000 // as an inline member function. A Lambda can be used legally
1001 // either as an in-class member initializer or a default argument. These
1002 // are parsed once the class has been marked complete and so the containing
1003 // context would be the nested class (when the lambda is defined in one);
1004 // If the class is not complete, then the lambda is being used in an
1005 // ill-formed fashion (such as to specify the width of a bit-field, or
1006 // in an array-bound) - in which case we still want to return the
1007 // lexically containing DC (which could be a nested class).
1008 if (isa<FunctionDecl>(DC) && !isLambdaCallOperator(DC)) {
1009 DC = DC->getLexicalParent();
1011 // A function not defined within a class will always return to its
1013 if (!isa<CXXRecordDecl>(DC))
1016 // A C++ inline method/friend is parsed *after* the topmost class
1017 // it was declared in is fully parsed ("complete"); the topmost
1018 // class is the context we need to return to.
1019 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent()))
1022 // Return the declaration context of the topmost class the inline method is
1027 return DC->getLexicalParent();
1030 void Sema::PushDeclContext(Scope *S, DeclContext *DC) {
1031 assert(getContainingDC(DC) == CurContext &&
1032 "The next DeclContext should be lexically contained in the current one.");
1037 void Sema::PopDeclContext() {
1038 assert(CurContext && "DeclContext imbalance!");
1040 CurContext = getContainingDC(CurContext);
1041 assert(CurContext && "Popped translation unit!");
1044 /// EnterDeclaratorContext - Used when we must lookup names in the context
1045 /// of a declarator's nested name specifier.
1047 void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) {
1048 // C++0x [basic.lookup.unqual]p13:
1049 // A name used in the definition of a static data member of class
1050 // X (after the qualified-id of the static member) is looked up as
1051 // if the name was used in a member function of X.
1052 // C++0x [basic.lookup.unqual]p14:
1053 // If a variable member of a namespace is defined outside of the
1054 // scope of its namespace then any name used in the definition of
1055 // the variable member (after the declarator-id) is looked up as
1056 // if the definition of the variable member occurred in its
1058 // Both of these imply that we should push a scope whose context
1059 // is the semantic context of the declaration. We can't use
1060 // PushDeclContext here because that context is not necessarily
1061 // lexically contained in the current context. Fortunately,
1062 // the containing scope should have the appropriate information.
1064 assert(!S->getEntity() && "scope already has entity");
1067 Scope *Ancestor = S->getParent();
1068 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1069 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch");
1076 void Sema::ExitDeclaratorContext(Scope *S) {
1077 assert(S->getEntity() == CurContext && "Context imbalance!");
1079 // Switch back to the lexical context. The safety of this is
1080 // enforced by an assert in EnterDeclaratorContext.
1081 Scope *Ancestor = S->getParent();
1082 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent();
1083 CurContext = Ancestor->getEntity();
1085 // We don't need to do anything with the scope, which is going to
1090 void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) {
1091 // We assume that the caller has already called
1092 // ActOnReenterTemplateScope so getTemplatedDecl() works.
1093 FunctionDecl *FD = D->getAsFunction();
1097 // Same implementation as PushDeclContext, but enters the context
1098 // from the lexical parent, rather than the top-level class.
1099 assert(CurContext == FD->getLexicalParent() &&
1100 "The next DeclContext should be lexically contained in the current one.");
1102 S->setEntity(CurContext);
1104 for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) {
1105 ParmVarDecl *Param = FD->getParamDecl(P);
1106 // If the parameter has an identifier, then add it to the scope
1107 if (Param->getIdentifier()) {
1109 IdResolver.AddDecl(Param);
1115 void Sema::ActOnExitFunctionContext() {
1116 // Same implementation as PopDeclContext, but returns to the lexical parent,
1117 // rather than the top-level class.
1118 assert(CurContext && "DeclContext imbalance!");
1119 CurContext = CurContext->getLexicalParent();
1120 assert(CurContext && "Popped translation unit!");
1124 /// \brief Determine whether we allow overloading of the function
1125 /// PrevDecl with another declaration.
1127 /// This routine determines whether overloading is possible, not
1128 /// whether some new function is actually an overload. It will return
1129 /// true in C++ (where we can always provide overloads) or, as an
1130 /// extension, in C when the previous function is already an
1131 /// overloaded function declaration or has the "overloadable"
1133 static bool AllowOverloadingOfFunction(LookupResult &Previous,
1134 ASTContext &Context) {
1135 if (Context.getLangOpts().CPlusPlus)
1138 if (Previous.getResultKind() == LookupResult::FoundOverloaded)
1141 return (Previous.getResultKind() == LookupResult::Found
1142 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>());
1145 /// Add this decl to the scope shadowed decl chains.
1146 void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) {
1147 // Move up the scope chain until we find the nearest enclosing
1148 // non-transparent context. The declaration will be introduced into this
1150 while (S->getEntity() && S->getEntity()->isTransparentContext())
1153 // Add scoped declarations into their context, so that they can be
1154 // found later. Declarations without a context won't be inserted
1155 // into any context.
1157 CurContext->addDecl(D);
1159 // Out-of-line definitions shouldn't be pushed into scope in C++, unless they
1160 // are function-local declarations.
1161 if (getLangOpts().CPlusPlus && D->isOutOfLine() &&
1162 !D->getDeclContext()->getRedeclContext()->Equals(
1163 D->getLexicalDeclContext()->getRedeclContext()) &&
1164 !D->getLexicalDeclContext()->isFunctionOrMethod())
1167 // Template instantiations should also not be pushed into scope.
1168 if (isa<FunctionDecl>(D) &&
1169 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization())
1172 // If this replaces anything in the current scope,
1173 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()),
1174 IEnd = IdResolver.end();
1175 for (; I != IEnd; ++I) {
1176 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) {
1178 IdResolver.RemoveDecl(*I);
1180 // Should only need to replace one decl.
1187 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) {
1188 // Implicitly-generated labels may end up getting generated in an order that
1189 // isn't strictly lexical, which breaks name lookup. Be careful to insert
1190 // the label at the appropriate place in the identifier chain.
1191 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) {
1192 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext();
1193 if (IDC == CurContext) {
1194 if (!S->isDeclScope(*I))
1196 } else if (IDC->Encloses(CurContext))
1200 IdResolver.InsertDeclAfter(I, D);
1202 IdResolver.AddDecl(D);
1206 void Sema::pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name) {
1207 if (IdResolver.tryAddTopLevelDecl(D, Name) && TUScope)
1208 TUScope->AddDecl(D);
1211 bool Sema::isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S,
1212 bool AllowInlineNamespace) {
1213 return IdResolver.isDeclInScope(D, Ctx, S, AllowInlineNamespace);
1216 Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) {
1217 DeclContext *TargetDC = DC->getPrimaryContext();
1219 if (DeclContext *ScopeDC = S->getEntity())
1220 if (ScopeDC->getPrimaryContext() == TargetDC)
1222 } while ((S = S->getParent()));
1227 static bool isOutOfScopePreviousDeclaration(NamedDecl *,
1231 /// Filters out lookup results that don't fall within the given scope
1232 /// as determined by isDeclInScope.
1233 void Sema::FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S,
1234 bool ConsiderLinkage,
1235 bool AllowInlineNamespace) {
1236 LookupResult::Filter F = R.makeFilter();
1237 while (F.hasNext()) {
1238 NamedDecl *D = F.next();
1240 if (isDeclInScope(D, Ctx, S, AllowInlineNamespace))
1243 if (ConsiderLinkage && isOutOfScopePreviousDeclaration(D, Ctx, Context))
1252 static bool isUsingDecl(NamedDecl *D) {
1253 return isa<UsingShadowDecl>(D) ||
1254 isa<UnresolvedUsingTypenameDecl>(D) ||
1255 isa<UnresolvedUsingValueDecl>(D);
1258 /// Removes using shadow declarations from the lookup results.
1259 static void RemoveUsingDecls(LookupResult &R) {
1260 LookupResult::Filter F = R.makeFilter();
1262 if (isUsingDecl(F.next()))
1268 /// \brief Check for this common pattern:
1271 /// S(const S&); // DO NOT IMPLEMENT
1272 /// void operator=(const S&); // DO NOT IMPLEMENT
1275 static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) {
1276 // FIXME: Should check for private access too but access is set after we get
1278 if (D->doesThisDeclarationHaveABody())
1281 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D))
1282 return CD->isCopyConstructor();
1283 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
1284 return Method->isCopyAssignmentOperator();
1288 // We need this to handle
1291 // void *foo() { return 0; }
1294 // When we see foo we don't know if after the typedef we will get 'A' or '*A'
1295 // for example. If 'A', foo will have external linkage. If we have '*A',
1296 // foo will have no linkage. Since we can't know until we get to the end
1297 // of the typedef, this function finds out if D might have non-external linkage.
1298 // Callers should verify at the end of the TU if it D has external linkage or
1300 bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) {
1301 const DeclContext *DC = D->getDeclContext();
1302 while (!DC->isTranslationUnit()) {
1303 if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){
1304 if (!RD->hasNameForLinkage())
1307 DC = DC->getParent();
1310 return !D->isExternallyVisible();
1313 // FIXME: This needs to be refactored; some other isInMainFile users want
1315 static bool isMainFileLoc(const Sema &S, SourceLocation Loc) {
1316 if (S.TUKind != TU_Complete)
1318 return S.SourceMgr.isInMainFile(Loc);
1321 bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const {
1324 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>())
1327 // Ignore all entities declared within templates, and out-of-line definitions
1328 // of members of class templates.
1329 if (D->getDeclContext()->isDependentContext() ||
1330 D->getLexicalDeclContext()->isDependentContext())
1333 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1334 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1337 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
1338 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD))
1341 // 'static inline' functions are defined in headers; don't warn.
1342 if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation()))
1346 if (FD->doesThisDeclarationHaveABody() &&
1347 Context.DeclMustBeEmitted(FD))
1349 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1350 // Constants and utility variables are defined in headers with internal
1351 // linkage; don't warn. (Unlike functions, there isn't a convenient marker
1353 if (!isMainFileLoc(*this, VD->getLocation()))
1356 if (Context.DeclMustBeEmitted(VD))
1359 if (VD->isStaticDataMember() &&
1360 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1366 // Only warn for unused decls internal to the translation unit.
1367 // FIXME: This seems like a bogus check; it suppresses -Wunused-function
1368 // for inline functions defined in the main source file, for instance.
1369 return mightHaveNonExternalLinkage(D);
1372 void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) {
1376 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1377 const FunctionDecl *First = FD->getFirstDecl();
1378 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1379 return; // First should already be in the vector.
1382 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1383 const VarDecl *First = VD->getFirstDecl();
1384 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First))
1385 return; // First should already be in the vector.
1388 if (ShouldWarnIfUnusedFileScopedDecl(D))
1389 UnusedFileScopedDecls.push_back(D);
1392 static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
1393 if (D->isInvalidDecl())
1396 if (D->isReferenced() || D->isUsed() || D->hasAttr<UnusedAttr>() ||
1397 D->hasAttr<ObjCPreciseLifetimeAttr>())
1400 if (isa<LabelDecl>(D))
1403 // Except for labels, we only care about unused decls that are local to
1405 bool WithinFunction = D->getDeclContext()->isFunctionOrMethod();
1406 if (const auto *R = dyn_cast<CXXRecordDecl>(D->getDeclContext()))
1407 // For dependent types, the diagnostic is deferred.
1409 WithinFunction || (R->isLocalClass() && !R->isDependentType());
1410 if (!WithinFunction)
1413 if (isa<TypedefNameDecl>(D))
1416 // White-list anything that isn't a local variable.
1417 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D))
1420 // Types of valid local variables should be complete, so this should succeed.
1421 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1423 // White-list anything with an __attribute__((unused)) type.
1424 QualType Ty = VD->getType();
1426 // Only look at the outermost level of typedef.
1427 if (const TypedefType *TT = Ty->getAs<TypedefType>()) {
1428 if (TT->getDecl()->hasAttr<UnusedAttr>())
1432 // If we failed to complete the type for some reason, or if the type is
1433 // dependent, don't diagnose the variable.
1434 if (Ty->isIncompleteType() || Ty->isDependentType())
1437 if (const TagType *TT = Ty->getAs<TagType>()) {
1438 const TagDecl *Tag = TT->getDecl();
1439 if (Tag->hasAttr<UnusedAttr>())
1442 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) {
1443 if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>())
1446 if (const Expr *Init = VD->getInit()) {
1447 if (const ExprWithCleanups *Cleanups =
1448 dyn_cast<ExprWithCleanups>(Init))
1449 Init = Cleanups->getSubExpr();
1450 const CXXConstructExpr *Construct =
1451 dyn_cast<CXXConstructExpr>(Init);
1452 if (Construct && !Construct->isElidable()) {
1453 CXXConstructorDecl *CD = Construct->getConstructor();
1454 if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>())
1461 // TODO: __attribute__((unused)) templates?
1467 static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx,
1469 if (isa<LabelDecl>(D)) {
1470 SourceLocation AfterColon = Lexer::findLocationAfterToken(D->getLocEnd(),
1471 tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(), true);
1472 if (AfterColon.isInvalid())
1474 Hint = FixItHint::CreateRemoval(CharSourceRange::
1475 getCharRange(D->getLocStart(), AfterColon));
1480 void Sema::DiagnoseUnusedNestedTypedefs(const RecordDecl *D) {
1481 if (D->getTypeForDecl()->isDependentType())
1484 for (auto *TmpD : D->decls()) {
1485 if (const auto *T = dyn_cast<TypedefNameDecl>(TmpD))
1486 DiagnoseUnusedDecl(T);
1487 else if(const auto *R = dyn_cast<RecordDecl>(TmpD))
1488 DiagnoseUnusedNestedTypedefs(R);
1492 /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used
1493 /// unless they are marked attr(unused).
1494 void Sema::DiagnoseUnusedDecl(const NamedDecl *D) {
1495 if (!ShouldDiagnoseUnusedDecl(D))
1498 if (auto *TD = dyn_cast<TypedefNameDecl>(D)) {
1499 // typedefs can be referenced later on, so the diagnostics are emitted
1500 // at end-of-translation-unit.
1501 UnusedLocalTypedefNameCandidates.insert(TD);
1506 GenerateFixForUnusedDecl(D, Context, Hint);
1509 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable())
1510 DiagID = diag::warn_unused_exception_param;
1511 else if (isa<LabelDecl>(D))
1512 DiagID = diag::warn_unused_label;
1514 DiagID = diag::warn_unused_variable;
1516 Diag(D->getLocation(), DiagID) << D->getDeclName() << Hint;
1519 static void CheckPoppedLabel(LabelDecl *L, Sema &S) {
1520 // Verify that we have no forward references left. If so, there was a goto
1521 // or address of a label taken, but no definition of it. Label fwd
1522 // definitions are indicated with a null substmt which is also not a resolved
1523 // MS inline assembly label name.
1524 bool Diagnose = false;
1525 if (L->isMSAsmLabel())
1526 Diagnose = !L->isResolvedMSAsmLabel();
1528 Diagnose = L->getStmt() == nullptr;
1530 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName();
1533 void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) {
1534 S->mergeNRVOIntoParent();
1536 if (S->decl_empty()) return;
1537 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) &&
1538 "Scope shouldn't contain decls!");
1540 for (auto *TmpD : S->decls()) {
1541 assert(TmpD && "This decl didn't get pushed??");
1543 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?");
1544 NamedDecl *D = cast<NamedDecl>(TmpD);
1546 if (!D->getDeclName()) continue;
1548 // Diagnose unused variables in this scope.
1549 if (!S->hasUnrecoverableErrorOccurred()) {
1550 DiagnoseUnusedDecl(D);
1551 if (const auto *RD = dyn_cast<RecordDecl>(D))
1552 DiagnoseUnusedNestedTypedefs(RD);
1555 // If this was a forward reference to a label, verify it was defined.
1556 if (LabelDecl *LD = dyn_cast<LabelDecl>(D))
1557 CheckPoppedLabel(LD, *this);
1559 // Remove this name from our lexical scope.
1560 IdResolver.RemoveDecl(D);
1564 /// \brief Look for an Objective-C class in the translation unit.
1566 /// \param Id The name of the Objective-C class we're looking for. If
1567 /// typo-correction fixes this name, the Id will be updated
1568 /// to the fixed name.
1570 /// \param IdLoc The location of the name in the translation unit.
1572 /// \param DoTypoCorrection If true, this routine will attempt typo correction
1573 /// if there is no class with the given name.
1575 /// \returns The declaration of the named Objective-C class, or NULL if the
1576 /// class could not be found.
1577 ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id,
1578 SourceLocation IdLoc,
1579 bool DoTypoCorrection) {
1580 // The third "scope" argument is 0 since we aren't enabling lazy built-in
1581 // creation from this context.
1582 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName);
1584 if (!IDecl && DoTypoCorrection) {
1585 // Perform typo correction at the given location, but only if we
1586 // find an Objective-C class name.
1587 if (TypoCorrection C = CorrectTypo(
1588 DeclarationNameInfo(Id, IdLoc), LookupOrdinaryName, TUScope, nullptr,
1589 llvm::make_unique<DeclFilterCCC<ObjCInterfaceDecl>>(),
1590 CTK_ErrorRecovery)) {
1591 diagnoseTypo(C, PDiag(diag::err_undef_interface_suggest) << Id);
1592 IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>();
1593 Id = IDecl->getIdentifier();
1596 ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl);
1597 // This routine must always return a class definition, if any.
1598 if (Def && Def->getDefinition())
1599 Def = Def->getDefinition();
1603 /// getNonFieldDeclScope - Retrieves the innermost scope, starting
1604 /// from S, where a non-field would be declared. This routine copes
1605 /// with the difference between C and C++ scoping rules in structs and
1606 /// unions. For example, the following code is well-formed in C but
1607 /// ill-formed in C++:
1613 /// void test_S6() {
1618 /// For the declaration of BAR, this routine will return a different
1619 /// scope. The scope S will be the scope of the unnamed enumeration
1620 /// within S6. In C++, this routine will return the scope associated
1621 /// with S6, because the enumeration's scope is a transparent
1622 /// context but structures can contain non-field names. In C, this
1623 /// routine will return the translation unit scope, since the
1624 /// enumeration's scope is a transparent context and structures cannot
1625 /// contain non-field names.
1626 Scope *Sema::getNonFieldDeclScope(Scope *S) {
1627 while (((S->getFlags() & Scope::DeclScope) == 0) ||
1628 (S->getEntity() && S->getEntity()->isTransparentContext()) ||
1629 (S->isClassScope() && !getLangOpts().CPlusPlus))
1634 /// \brief Looks up the declaration of "struct objc_super" and
1635 /// saves it for later use in building builtin declaration of
1636 /// objc_msgSendSuper and objc_msgSendSuper_stret. If no such
1637 /// pre-existing declaration exists no action takes place.
1638 static void LookupPredefedObjCSuperType(Sema &ThisSema, Scope *S,
1639 IdentifierInfo *II) {
1640 if (!II->isStr("objc_msgSendSuper"))
1642 ASTContext &Context = ThisSema.Context;
1644 LookupResult Result(ThisSema, &Context.Idents.get("objc_super"),
1645 SourceLocation(), Sema::LookupTagName);
1646 ThisSema.LookupName(Result, S);
1647 if (Result.getResultKind() == LookupResult::Found)
1648 if (const TagDecl *TD = Result.getAsSingle<TagDecl>())
1649 Context.setObjCSuperType(Context.getTagDeclType(TD));
1652 static StringRef getHeaderName(ASTContext::GetBuiltinTypeError Error) {
1654 case ASTContext::GE_None:
1656 case ASTContext::GE_Missing_stdio:
1658 case ASTContext::GE_Missing_setjmp:
1660 case ASTContext::GE_Missing_ucontext:
1661 return "ucontext.h";
1663 llvm_unreachable("unhandled error kind");
1666 /// LazilyCreateBuiltin - The specified Builtin-ID was first used at
1667 /// file scope. lazily create a decl for it. ForRedeclaration is true
1668 /// if we're creating this built-in in anticipation of redeclaring the
1670 NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID,
1671 Scope *S, bool ForRedeclaration,
1672 SourceLocation Loc) {
1673 LookupPredefedObjCSuperType(*this, S, II);
1675 ASTContext::GetBuiltinTypeError Error;
1676 QualType R = Context.GetBuiltinType(ID, Error);
1678 if (ForRedeclaration)
1679 Diag(Loc, diag::warn_implicit_decl_requires_sysheader)
1680 << getHeaderName(Error)
1681 << Context.BuiltinInfo.GetName(ID);
1685 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(ID)) {
1686 Diag(Loc, diag::ext_implicit_lib_function_decl)
1687 << Context.BuiltinInfo.GetName(ID)
1689 if (Context.BuiltinInfo.getHeaderName(ID) &&
1690 !Diags.isIgnored(diag::ext_implicit_lib_function_decl, Loc))
1691 Diag(Loc, diag::note_include_header_or_declare)
1692 << Context.BuiltinInfo.getHeaderName(ID)
1693 << Context.BuiltinInfo.GetName(ID);
1696 DeclContext *Parent = Context.getTranslationUnitDecl();
1697 if (getLangOpts().CPlusPlus) {
1698 LinkageSpecDecl *CLinkageDecl =
1699 LinkageSpecDecl::Create(Context, Parent, Loc, Loc,
1700 LinkageSpecDecl::lang_c, false);
1701 CLinkageDecl->setImplicit();
1702 Parent->addDecl(CLinkageDecl);
1703 Parent = CLinkageDecl;
1706 FunctionDecl *New = FunctionDecl::Create(Context,
1708 Loc, Loc, II, R, /*TInfo=*/nullptr,
1711 /*hasPrototype=*/true);
1714 // Create Decl objects for each parameter, adding them to the
1716 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) {
1717 SmallVector<ParmVarDecl*, 16> Params;
1718 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
1720 ParmVarDecl::Create(Context, New, SourceLocation(), SourceLocation(),
1721 nullptr, FT->getParamType(i), /*TInfo=*/nullptr,
1723 parm->setScopeInfo(0, i);
1724 Params.push_back(parm);
1726 New->setParams(Params);
1729 AddKnownFunctionAttributes(New);
1730 RegisterLocallyScopedExternCDecl(New, S);
1732 // TUScope is the translation-unit scope to insert this function into.
1733 // FIXME: This is hideous. We need to teach PushOnScopeChains to
1734 // relate Scopes to DeclContexts, and probably eliminate CurContext
1735 // entirely, but we're not there yet.
1736 DeclContext *SavedContext = CurContext;
1737 CurContext = Parent;
1738 PushOnScopeChains(New, TUScope);
1739 CurContext = SavedContext;
1743 /// \brief Filter out any previous declarations that the given declaration
1744 /// should not consider because they are not permitted to conflict, e.g.,
1745 /// because they come from hidden sub-modules and do not refer to the same
1747 static void filterNonConflictingPreviousDecls(ASTContext &context,
1749 LookupResult &previous){
1750 // This is only interesting when modules are enabled.
1751 if (!context.getLangOpts().Modules)
1754 // Empty sets are uninteresting.
1755 if (previous.empty())
1758 LookupResult::Filter filter = previous.makeFilter();
1759 while (filter.hasNext()) {
1760 NamedDecl *old = filter.next();
1762 // Non-hidden declarations are never ignored.
1763 if (!old->isHidden())
1766 if (!old->isExternallyVisible())
1773 /// Typedef declarations don't have linkage, but they still denote the same
1774 /// entity if their types are the same.
1775 /// FIXME: This is notionally doing the same thing as ASTReaderDecl's
1777 static void filterNonConflictingPreviousTypedefDecls(ASTContext &Context,
1778 TypedefNameDecl *Decl,
1779 LookupResult &Previous) {
1780 // This is only interesting when modules are enabled.
1781 if (!Context.getLangOpts().Modules)
1784 // Empty sets are uninteresting.
1785 if (Previous.empty())
1788 LookupResult::Filter Filter = Previous.makeFilter();
1789 while (Filter.hasNext()) {
1790 NamedDecl *Old = Filter.next();
1792 // Non-hidden declarations are never ignored.
1793 if (!Old->isHidden())
1796 // Declarations of the same entity are not ignored, even if they have
1797 // different linkages.
1798 if (auto *OldTD = dyn_cast<TypedefNameDecl>(Old))
1799 if (Context.hasSameType(OldTD->getUnderlyingType(),
1800 Decl->getUnderlyingType()))
1803 if (!Old->isExternallyVisible())
1810 bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) {
1812 if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old))
1813 OldType = OldTypedef->getUnderlyingType();
1815 OldType = Context.getTypeDeclType(Old);
1816 QualType NewType = New->getUnderlyingType();
1818 if (NewType->isVariablyModifiedType()) {
1819 // Must not redefine a typedef with a variably-modified type.
1820 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1821 Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef)
1823 if (Old->getLocation().isValid())
1824 Diag(Old->getLocation(), diag::note_previous_definition);
1825 New->setInvalidDecl();
1829 if (OldType != NewType &&
1830 !OldType->isDependentType() &&
1831 !NewType->isDependentType() &&
1832 !Context.hasSameType(OldType, NewType)) {
1833 int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0;
1834 Diag(New->getLocation(), diag::err_redefinition_different_typedef)
1835 << Kind << NewType << OldType;
1836 if (Old->getLocation().isValid())
1837 Diag(Old->getLocation(), diag::note_previous_definition);
1838 New->setInvalidDecl();
1844 /// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the
1845 /// same name and scope as a previous declaration 'Old'. Figure out
1846 /// how to resolve this situation, merging decls or emitting
1847 /// diagnostics as appropriate. If there was an error, set New to be invalid.
1849 void Sema::MergeTypedefNameDecl(TypedefNameDecl *New, LookupResult &OldDecls) {
1850 // If the new decl is known invalid already, don't bother doing any
1852 if (New->isInvalidDecl()) return;
1854 // Allow multiple definitions for ObjC built-in typedefs.
1855 // FIXME: Verify the underlying types are equivalent!
1856 if (getLangOpts().ObjC1) {
1857 const IdentifierInfo *TypeID = New->getIdentifier();
1858 switch (TypeID->getLength()) {
1862 if (!TypeID->isStr("id"))
1864 QualType T = New->getUnderlyingType();
1865 if (!T->isPointerType())
1867 if (!T->isVoidPointerType()) {
1868 QualType PT = T->getAs<PointerType>()->getPointeeType();
1869 if (!PT->isStructureType())
1872 Context.setObjCIdRedefinitionType(T);
1873 // Install the built-in type for 'id', ignoring the current definition.
1874 New->setTypeForDecl(Context.getObjCIdType().getTypePtr());
1878 if (!TypeID->isStr("Class"))
1880 Context.setObjCClassRedefinitionType(New->getUnderlyingType());
1881 // Install the built-in type for 'Class', ignoring the current definition.
1882 New->setTypeForDecl(Context.getObjCClassType().getTypePtr());
1885 if (!TypeID->isStr("SEL"))
1887 Context.setObjCSelRedefinitionType(New->getUnderlyingType());
1888 // Install the built-in type for 'SEL', ignoring the current definition.
1889 New->setTypeForDecl(Context.getObjCSelType().getTypePtr());
1892 // Fall through - the typedef name was not a builtin type.
1895 // Verify the old decl was also a type.
1896 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>();
1898 Diag(New->getLocation(), diag::err_redefinition_different_kind)
1899 << New->getDeclName();
1901 NamedDecl *OldD = OldDecls.getRepresentativeDecl();
1902 if (OldD->getLocation().isValid())
1903 Diag(OldD->getLocation(), diag::note_previous_definition);
1905 return New->setInvalidDecl();
1908 // If the old declaration is invalid, just give up here.
1909 if (Old->isInvalidDecl())
1910 return New->setInvalidDecl();
1912 // If the typedef types are not identical, reject them in all languages and
1913 // with any extensions enabled.
1914 if (isIncompatibleTypedef(Old, New))
1917 // The types match. Link up the redeclaration chain and merge attributes if
1918 // the old declaration was a typedef.
1919 if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) {
1920 New->setPreviousDecl(Typedef);
1921 mergeDeclAttributes(New, Old);
1924 if (getLangOpts().MicrosoftExt)
1927 if (getLangOpts().CPlusPlus) {
1928 // C++ [dcl.typedef]p2:
1929 // In a given non-class scope, a typedef specifier can be used to
1930 // redefine the name of any type declared in that scope to refer
1931 // to the type to which it already refers.
1932 if (!isa<CXXRecordDecl>(CurContext))
1935 // C++0x [dcl.typedef]p4:
1936 // In a given class scope, a typedef specifier can be used to redefine
1937 // any class-name declared in that scope that is not also a typedef-name
1938 // to refer to the type to which it already refers.
1940 // This wording came in via DR424, which was a correction to the
1941 // wording in DR56, which accidentally banned code like:
1944 // typedef struct A { } A;
1947 // in the C++03 standard. We implement the C++0x semantics, which
1948 // allow the above but disallow
1955 // since that was the intent of DR56.
1956 if (!isa<TypedefNameDecl>(Old))
1959 Diag(New->getLocation(), diag::err_redefinition)
1960 << New->getDeclName();
1961 Diag(Old->getLocation(), diag::note_previous_definition);
1962 return New->setInvalidDecl();
1965 // Modules always permit redefinition of typedefs, as does C11.
1966 if (getLangOpts().Modules || getLangOpts().C11)
1969 // If we have a redefinition of a typedef in C, emit a warning. This warning
1970 // is normally mapped to an error, but can be controlled with
1971 // -Wtypedef-redefinition. If either the original or the redefinition is
1972 // in a system header, don't emit this for compatibility with GCC.
1973 if (getDiagnostics().getSuppressSystemWarnings() &&
1974 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) ||
1975 Context.getSourceManager().isInSystemHeader(New->getLocation())))
1978 Diag(New->getLocation(), diag::ext_redefinition_of_typedef)
1979 << New->getDeclName();
1980 Diag(Old->getLocation(), diag::note_previous_definition);
1984 /// DeclhasAttr - returns true if decl Declaration already has the target
1986 static bool DeclHasAttr(const Decl *D, const Attr *A) {
1987 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A);
1988 const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A);
1989 for (const auto *i : D->attrs())
1990 if (i->getKind() == A->getKind()) {
1992 if (Ann->getAnnotation() == cast<AnnotateAttr>(i)->getAnnotation())
1996 // FIXME: Don't hardcode this check
1997 if (OA && isa<OwnershipAttr>(i))
1998 return OA->getOwnKind() == cast<OwnershipAttr>(i)->getOwnKind();
2005 static bool isAttributeTargetADefinition(Decl *D) {
2006 if (VarDecl *VD = dyn_cast<VarDecl>(D))
2007 return VD->isThisDeclarationADefinition();
2008 if (TagDecl *TD = dyn_cast<TagDecl>(D))
2009 return TD->isCompleteDefinition() || TD->isBeingDefined();
2013 /// Merge alignment attributes from \p Old to \p New, taking into account the
2014 /// special semantics of C11's _Alignas specifier and C++11's alignas attribute.
2016 /// \return \c true if any attributes were added to \p New.
2017 static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) {
2018 // Look for alignas attributes on Old, and pick out whichever attribute
2019 // specifies the strictest alignment requirement.
2020 AlignedAttr *OldAlignasAttr = nullptr;
2021 AlignedAttr *OldStrictestAlignAttr = nullptr;
2022 unsigned OldAlign = 0;
2023 for (auto *I : Old->specific_attrs<AlignedAttr>()) {
2024 // FIXME: We have no way of representing inherited dependent alignments
2026 // template<int A, int B> struct alignas(A) X;
2027 // template<int A, int B> struct alignas(B) X {};
2028 // For now, we just ignore any alignas attributes which are not on the
2029 // definition in such a case.
2030 if (I->isAlignmentDependent())
2036 unsigned Align = I->getAlignment(S.Context);
2037 if (Align > OldAlign) {
2039 OldStrictestAlignAttr = I;
2043 // Look for alignas attributes on New.
2044 AlignedAttr *NewAlignasAttr = nullptr;
2045 unsigned NewAlign = 0;
2046 for (auto *I : New->specific_attrs<AlignedAttr>()) {
2047 if (I->isAlignmentDependent())
2053 unsigned Align = I->getAlignment(S.Context);
2054 if (Align > NewAlign)
2058 if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) {
2059 // Both declarations have 'alignas' attributes. We require them to match.
2060 // C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but
2061 // fall short. (If two declarations both have alignas, they must both match
2062 // every definition, and so must match each other if there is a definition.)
2064 // If either declaration only contains 'alignas(0)' specifiers, then it
2065 // specifies the natural alignment for the type.
2066 if (OldAlign == 0 || NewAlign == 0) {
2068 if (ValueDecl *VD = dyn_cast<ValueDecl>(New))
2071 Ty = S.Context.getTagDeclType(cast<TagDecl>(New));
2074 OldAlign = S.Context.getTypeAlign(Ty);
2076 NewAlign = S.Context.getTypeAlign(Ty);
2079 if (OldAlign != NewAlign) {
2080 S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch)
2081 << (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity()
2082 << (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity();
2083 S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration);
2087 if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) {
2088 // C++11 [dcl.align]p6:
2089 // if any declaration of an entity has an alignment-specifier,
2090 // every defining declaration of that entity shall specify an
2091 // equivalent alignment.
2093 // If the definition of an object does not have an alignment
2094 // specifier, any other declaration of that object shall also
2095 // have no alignment specifier.
2096 S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition)
2098 S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration)
2102 bool AnyAdded = false;
2104 // Ensure we have an attribute representing the strictest alignment.
2105 if (OldAlign > NewAlign) {
2106 AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context);
2107 Clone->setInherited(true);
2108 New->addAttr(Clone);
2112 // Ensure we have an alignas attribute if the old declaration had one.
2113 if (OldAlignasAttr && !NewAlignasAttr &&
2114 !(AnyAdded && OldStrictestAlignAttr->isAlignas())) {
2115 AlignedAttr *Clone = OldAlignasAttr->clone(S.Context);
2116 Clone->setInherited(true);
2117 New->addAttr(Clone);
2124 static bool mergeDeclAttribute(Sema &S, NamedDecl *D,
2125 const InheritableAttr *Attr, bool Override) {
2126 InheritableAttr *NewAttr = nullptr;
2127 unsigned AttrSpellingListIndex = Attr->getSpellingListIndex();
2128 if (const auto *AA = dyn_cast<AvailabilityAttr>(Attr))
2129 NewAttr = S.mergeAvailabilityAttr(D, AA->getRange(), AA->getPlatform(),
2130 AA->getIntroduced(), AA->getDeprecated(),
2131 AA->getObsoleted(), AA->getUnavailable(),
2132 AA->getMessage(), Override,
2133 AttrSpellingListIndex);
2134 else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr))
2135 NewAttr = S.mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2136 AttrSpellingListIndex);
2137 else if (const auto *VA = dyn_cast<TypeVisibilityAttr>(Attr))
2138 NewAttr = S.mergeTypeVisibilityAttr(D, VA->getRange(), VA->getVisibility(),
2139 AttrSpellingListIndex);
2140 else if (const auto *ImportA = dyn_cast<DLLImportAttr>(Attr))
2141 NewAttr = S.mergeDLLImportAttr(D, ImportA->getRange(),
2142 AttrSpellingListIndex);
2143 else if (const auto *ExportA = dyn_cast<DLLExportAttr>(Attr))
2144 NewAttr = S.mergeDLLExportAttr(D, ExportA->getRange(),
2145 AttrSpellingListIndex);
2146 else if (const auto *FA = dyn_cast<FormatAttr>(Attr))
2147 NewAttr = S.mergeFormatAttr(D, FA->getRange(), FA->getType(),
2148 FA->getFormatIdx(), FA->getFirstArg(),
2149 AttrSpellingListIndex);
2150 else if (const auto *SA = dyn_cast<SectionAttr>(Attr))
2151 NewAttr = S.mergeSectionAttr(D, SA->getRange(), SA->getName(),
2152 AttrSpellingListIndex);
2153 else if (const auto *IA = dyn_cast<MSInheritanceAttr>(Attr))
2154 NewAttr = S.mergeMSInheritanceAttr(D, IA->getRange(), IA->getBestCase(),
2155 AttrSpellingListIndex,
2156 IA->getSemanticSpelling());
2157 else if (const auto *AA = dyn_cast<AlwaysInlineAttr>(Attr))
2158 NewAttr = S.mergeAlwaysInlineAttr(D, AA->getRange(),
2159 &S.Context.Idents.get(AA->getSpelling()),
2160 AttrSpellingListIndex);
2161 else if (const auto *MA = dyn_cast<MinSizeAttr>(Attr))
2162 NewAttr = S.mergeMinSizeAttr(D, MA->getRange(), AttrSpellingListIndex);
2163 else if (const auto *OA = dyn_cast<OptimizeNoneAttr>(Attr))
2164 NewAttr = S.mergeOptimizeNoneAttr(D, OA->getRange(), AttrSpellingListIndex);
2165 else if (isa<AlignedAttr>(Attr))
2166 // AlignedAttrs are handled separately, because we need to handle all
2167 // such attributes on a declaration at the same time.
2169 else if (isa<DeprecatedAttr>(Attr) && Override)
2171 else if (Attr->duplicatesAllowed() || !DeclHasAttr(D, Attr))
2172 NewAttr = cast<InheritableAttr>(Attr->clone(S.Context));
2175 NewAttr->setInherited(true);
2176 D->addAttr(NewAttr);
2183 static const Decl *getDefinition(const Decl *D) {
2184 if (const TagDecl *TD = dyn_cast<TagDecl>(D))
2185 return TD->getDefinition();
2186 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
2187 const VarDecl *Def = VD->getDefinition();
2190 return VD->getActingDefinition();
2192 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
2193 const FunctionDecl* Def;
2194 if (FD->isDefined(Def))
2200 static bool hasAttribute(const Decl *D, attr::Kind Kind) {
2201 for (const auto *Attribute : D->attrs())
2202 if (Attribute->getKind() == Kind)
2207 /// checkNewAttributesAfterDef - If we already have a definition, check that
2208 /// there are no new attributes in this declaration.
2209 static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) {
2210 if (!New->hasAttrs())
2213 const Decl *Def = getDefinition(Old);
2214 if (!Def || Def == New)
2217 AttrVec &NewAttributes = New->getAttrs();
2218 for (unsigned I = 0, E = NewAttributes.size(); I != E;) {
2219 const Attr *NewAttribute = NewAttributes[I];
2221 if (isa<AliasAttr>(NewAttribute)) {
2222 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(New))
2223 S.CheckForFunctionRedefinition(FD, cast<FunctionDecl>(Def));
2225 VarDecl *VD = cast<VarDecl>(New);
2226 unsigned Diag = cast<VarDecl>(Def)->isThisDeclarationADefinition() ==
2227 VarDecl::TentativeDefinition
2228 ? diag::err_alias_after_tentative
2229 : diag::err_redefinition;
2230 S.Diag(VD->getLocation(), Diag) << VD->getDeclName();
2231 S.Diag(Def->getLocation(), diag::note_previous_definition);
2232 VD->setInvalidDecl();
2238 if (const VarDecl *VD = dyn_cast<VarDecl>(Def)) {
2239 // Tentative definitions are only interesting for the alias check above.
2240 if (VD->isThisDeclarationADefinition() != VarDecl::Definition) {
2246 if (hasAttribute(Def, NewAttribute->getKind())) {
2248 continue; // regular attr merging will take care of validating this.
2251 if (isa<C11NoReturnAttr>(NewAttribute)) {
2252 // C's _Noreturn is allowed to be added to a function after it is defined.
2255 } else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) {
2256 if (AA->isAlignas()) {
2257 // C++11 [dcl.align]p6:
2258 // if any declaration of an entity has an alignment-specifier,
2259 // every defining declaration of that entity shall specify an
2260 // equivalent alignment.
2262 // If the definition of an object does not have an alignment
2263 // specifier, any other declaration of that object shall also
2264 // have no alignment specifier.
2265 S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition)
2267 S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration)
2269 NewAttributes.erase(NewAttributes.begin() + I);
2275 S.Diag(NewAttribute->getLocation(),
2276 diag::warn_attribute_precede_definition);
2277 S.Diag(Def->getLocation(), diag::note_previous_definition);
2278 NewAttributes.erase(NewAttributes.begin() + I);
2283 /// mergeDeclAttributes - Copy attributes from the Old decl to the New one.
2284 void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old,
2285 AvailabilityMergeKind AMK) {
2286 if (UsedAttr *OldAttr = Old->getMostRecentDecl()->getAttr<UsedAttr>()) {
2287 UsedAttr *NewAttr = OldAttr->clone(Context);
2288 NewAttr->setInherited(true);
2289 New->addAttr(NewAttr);
2292 if (!Old->hasAttrs() && !New->hasAttrs())
2295 // attributes declared post-definition are currently ignored
2296 checkNewAttributesAfterDef(*this, New, Old);
2298 if (!Old->hasAttrs())
2301 bool foundAny = New->hasAttrs();
2303 // Ensure that any moving of objects within the allocated map is done before
2305 if (!foundAny) New->setAttrs(AttrVec());
2307 for (auto *I : Old->specific_attrs<InheritableAttr>()) {
2308 bool Override = false;
2309 // Ignore deprecated/unavailable/availability attributes if requested.
2310 if (isa<DeprecatedAttr>(I) ||
2311 isa<UnavailableAttr>(I) ||
2312 isa<AvailabilityAttr>(I)) {
2317 case AMK_Redeclaration:
2327 if (isa<UsedAttr>(I))
2330 if (mergeDeclAttribute(*this, New, I, Override))
2334 if (mergeAlignedAttrs(*this, New, Old))
2337 if (!foundAny) New->dropAttrs();
2340 /// mergeParamDeclAttributes - Copy attributes from the old parameter
2342 static void mergeParamDeclAttributes(ParmVarDecl *newDecl,
2343 const ParmVarDecl *oldDecl,
2345 // C++11 [dcl.attr.depend]p2:
2346 // The first declaration of a function shall specify the
2347 // carries_dependency attribute for its declarator-id if any declaration
2348 // of the function specifies the carries_dependency attribute.
2349 const CarriesDependencyAttr *CDA = newDecl->getAttr<CarriesDependencyAttr>();
2350 if (CDA && !oldDecl->hasAttr<CarriesDependencyAttr>()) {
2351 S.Diag(CDA->getLocation(),
2352 diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/;
2353 // Find the first declaration of the parameter.
2354 // FIXME: Should we build redeclaration chains for function parameters?
2355 const FunctionDecl *FirstFD =
2356 cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDecl();
2357 const ParmVarDecl *FirstVD =
2358 FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex());
2359 S.Diag(FirstVD->getLocation(),
2360 diag::note_carries_dependency_missing_first_decl) << 1/*Param*/;
2363 if (!oldDecl->hasAttrs())
2366 bool foundAny = newDecl->hasAttrs();
2368 // Ensure that any moving of objects within the allocated map is
2369 // done before we process them.
2370 if (!foundAny) newDecl->setAttrs(AttrVec());
2372 for (const auto *I : oldDecl->specific_attrs<InheritableParamAttr>()) {
2373 if (!DeclHasAttr(newDecl, I)) {
2374 InheritableAttr *newAttr =
2375 cast<InheritableParamAttr>(I->clone(S.Context));
2376 newAttr->setInherited(true);
2377 newDecl->addAttr(newAttr);
2382 if (!foundAny) newDecl->dropAttrs();
2387 /// Used in MergeFunctionDecl to keep track of function parameters in
2389 struct GNUCompatibleParamWarning {
2390 ParmVarDecl *OldParm;
2391 ParmVarDecl *NewParm;
2392 QualType PromotedType;
2397 /// getSpecialMember - get the special member enum for a method.
2398 Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) {
2399 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
2400 if (Ctor->isDefaultConstructor())
2401 return Sema::CXXDefaultConstructor;
2403 if (Ctor->isCopyConstructor())
2404 return Sema::CXXCopyConstructor;
2406 if (Ctor->isMoveConstructor())
2407 return Sema::CXXMoveConstructor;
2408 } else if (isa<CXXDestructorDecl>(MD)) {
2409 return Sema::CXXDestructor;
2410 } else if (MD->isCopyAssignmentOperator()) {
2411 return Sema::CXXCopyAssignment;
2412 } else if (MD->isMoveAssignmentOperator()) {
2413 return Sema::CXXMoveAssignment;
2416 return Sema::CXXInvalid;
2419 // Determine whether the previous declaration was a definition, implicit
2420 // declaration, or a declaration.
2421 template <typename T>
2422 static std::pair<diag::kind, SourceLocation>
2423 getNoteDiagForInvalidRedeclaration(const T *Old, const T *New) {
2424 diag::kind PrevDiag;
2425 SourceLocation OldLocation = Old->getLocation();
2426 if (Old->isThisDeclarationADefinition())
2427 PrevDiag = diag::note_previous_definition;
2428 else if (Old->isImplicit()) {
2429 PrevDiag = diag::note_previous_implicit_declaration;
2430 if (OldLocation.isInvalid())
2431 OldLocation = New->getLocation();
2433 PrevDiag = diag::note_previous_declaration;
2434 return std::make_pair(PrevDiag, OldLocation);
2437 /// canRedefineFunction - checks if a function can be redefined. Currently,
2438 /// only extern inline functions can be redefined, and even then only in
2440 static bool canRedefineFunction(const FunctionDecl *FD,
2441 const LangOptions& LangOpts) {
2442 return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) &&
2443 !LangOpts.CPlusPlus &&
2444 FD->isInlineSpecified() &&
2445 FD->getStorageClass() == SC_Extern);
2448 const AttributedType *Sema::getCallingConvAttributedType(QualType T) const {
2449 const AttributedType *AT = T->getAs<AttributedType>();
2450 while (AT && !AT->isCallingConv())
2451 AT = AT->getModifiedType()->getAs<AttributedType>();
2455 template <typename T>
2456 static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) {
2457 const DeclContext *DC = Old->getDeclContext();
2461 LanguageLinkage OldLinkage = Old->getLanguageLinkage();
2462 if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext())
2464 if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext())
2469 /// MergeFunctionDecl - We just parsed a function 'New' from
2470 /// declarator D which has the same name and scope as a previous
2471 /// declaration 'Old'. Figure out how to resolve this situation,
2472 /// merging decls or emitting diagnostics as appropriate.
2474 /// In C++, New and Old must be declarations that are not
2475 /// overloaded. Use IsOverload to determine whether New and Old are
2476 /// overloaded, and to select the Old declaration that New should be
2479 /// Returns true if there was an error, false otherwise.
2480 bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
2481 Scope *S, bool MergeTypeWithOld) {
2482 // Verify the old decl was also a function.
2483 FunctionDecl *Old = OldD->getAsFunction();
2485 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) {
2486 if (New->getFriendObjectKind()) {
2487 Diag(New->getLocation(), diag::err_using_decl_friend);
2488 Diag(Shadow->getTargetDecl()->getLocation(),
2489 diag::note_using_decl_target);
2490 Diag(Shadow->getUsingDecl()->getLocation(),
2491 diag::note_using_decl) << 0;
2495 // C++11 [namespace.udecl]p14:
2496 // If a function declaration in namespace scope or block scope has the
2497 // same name and the same parameter-type-list as a function introduced
2498 // by a using-declaration, and the declarations do not declare the same
2499 // function, the program is ill-formed.
2501 // Check whether the two declarations might declare the same function.
2502 Old = dyn_cast<FunctionDecl>(Shadow->getTargetDecl());
2504 !Old->getDeclContext()->getRedeclContext()->Equals(
2505 New->getDeclContext()->getRedeclContext()) &&
2506 !(Old->isExternC() && New->isExternC()))
2510 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse);
2511 Diag(Shadow->getTargetDecl()->getLocation(),
2512 diag::note_using_decl_target);
2513 Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl) << 0;
2518 Diag(New->getLocation(), diag::err_redefinition_different_kind)
2519 << New->getDeclName();
2520 Diag(OldD->getLocation(), diag::note_previous_definition);
2525 // If the old declaration is invalid, just give up here.
2526 if (Old->isInvalidDecl())
2529 diag::kind PrevDiag;
2530 SourceLocation OldLocation;
2531 std::tie(PrevDiag, OldLocation) =
2532 getNoteDiagForInvalidRedeclaration(Old, New);
2534 // Don't complain about this if we're in GNU89 mode and the old function
2535 // is an extern inline function.
2536 // Don't complain about specializations. They are not supposed to have
2538 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) &&
2539 New->getStorageClass() == SC_Static &&
2540 Old->hasExternalFormalLinkage() &&
2541 !New->getTemplateSpecializationInfo() &&
2542 !canRedefineFunction(Old, getLangOpts())) {
2543 if (getLangOpts().MicrosoftExt) {
2544 Diag(New->getLocation(), diag::ext_static_non_static) << New;
2545 Diag(OldLocation, PrevDiag);
2547 Diag(New->getLocation(), diag::err_static_non_static) << New;
2548 Diag(OldLocation, PrevDiag);
2554 // If a function is first declared with a calling convention, but is later
2555 // declared or defined without one, all following decls assume the calling
2556 // convention of the first.
2558 // It's OK if a function is first declared without a calling convention,
2559 // but is later declared or defined with the default calling convention.
2561 // To test if either decl has an explicit calling convention, we look for
2562 // AttributedType sugar nodes on the type as written. If they are missing or
2563 // were canonicalized away, we assume the calling convention was implicit.
2565 // Note also that we DO NOT return at this point, because we still have
2566 // other tests to run.
2567 QualType OldQType = Context.getCanonicalType(Old->getType());
2568 QualType NewQType = Context.getCanonicalType(New->getType());
2569 const FunctionType *OldType = cast<FunctionType>(OldQType);
2570 const FunctionType *NewType = cast<FunctionType>(NewQType);
2571 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo();
2572 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo();
2573 bool RequiresAdjustment = false;
2575 if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) {
2576 FunctionDecl *First = Old->getFirstDecl();
2577 const FunctionType *FT =
2578 First->getType().getCanonicalType()->castAs<FunctionType>();
2579 FunctionType::ExtInfo FI = FT->getExtInfo();
2580 bool NewCCExplicit = getCallingConvAttributedType(New->getType());
2581 if (!NewCCExplicit) {
2582 // Inherit the CC from the previous declaration if it was specified
2583 // there but not here.
2584 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC());
2585 RequiresAdjustment = true;
2587 // Calling conventions aren't compatible, so complain.
2588 bool FirstCCExplicit = getCallingConvAttributedType(First->getType());
2589 Diag(New->getLocation(), diag::err_cconv_change)
2590 << FunctionType::getNameForCallConv(NewTypeInfo.getCC())
2592 << (!FirstCCExplicit ? "" :
2593 FunctionType::getNameForCallConv(FI.getCC()));
2595 // Put the note on the first decl, since it is the one that matters.
2596 Diag(First->getLocation(), diag::note_previous_declaration);
2601 // FIXME: diagnose the other way around?
2602 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) {
2603 NewTypeInfo = NewTypeInfo.withNoReturn(true);
2604 RequiresAdjustment = true;
2607 // Merge regparm attribute.
2608 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() ||
2609 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) {
2610 if (NewTypeInfo.getHasRegParm()) {
2611 Diag(New->getLocation(), diag::err_regparm_mismatch)
2612 << NewType->getRegParmType()
2613 << OldType->getRegParmType();
2614 Diag(OldLocation, diag::note_previous_declaration);
2618 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm());
2619 RequiresAdjustment = true;
2622 // Merge ns_returns_retained attribute.
2623 if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) {
2624 if (NewTypeInfo.getProducesResult()) {
2625 Diag(New->getLocation(), diag::err_returns_retained_mismatch);
2626 Diag(OldLocation, diag::note_previous_declaration);
2630 NewTypeInfo = NewTypeInfo.withProducesResult(true);
2631 RequiresAdjustment = true;
2634 if (RequiresAdjustment) {
2635 const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>();
2636 AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo);
2637 New->setType(QualType(AdjustedType, 0));
2638 NewQType = Context.getCanonicalType(New->getType());
2639 NewType = cast<FunctionType>(NewQType);
2642 // If this redeclaration makes the function inline, we may need to add it to
2643 // UndefinedButUsed.
2644 if (!Old->isInlined() && New->isInlined() &&
2645 !New->hasAttr<GNUInlineAttr>() &&
2646 (getLangOpts().CPlusPlus || !getLangOpts().GNUInline) &&
2647 Old->isUsed(false) &&
2648 !Old->isDefined() && !New->isThisDeclarationADefinition())
2649 UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(),
2652 // If this redeclaration makes it newly gnu_inline, we don't want to warn
2654 if (New->hasAttr<GNUInlineAttr>() &&
2655 Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) {
2656 UndefinedButUsed.erase(Old->getCanonicalDecl());
2659 if (getLangOpts().CPlusPlus) {
2661 // Certain function declarations cannot be overloaded:
2662 // -- Function declarations that differ only in the return type
2663 // cannot be overloaded.
2665 // Go back to the type source info to compare the declared return types,
2666 // per C++1y [dcl.type.auto]p13:
2667 // Redeclarations or specializations of a function or function template
2668 // with a declared return type that uses a placeholder type shall also
2669 // use that placeholder, not a deduced type.
2670 QualType OldDeclaredReturnType =
2671 (Old->getTypeSourceInfo()
2672 ? Old->getTypeSourceInfo()->getType()->castAs<FunctionType>()
2673 : OldType)->getReturnType();
2674 QualType NewDeclaredReturnType =
2675 (New->getTypeSourceInfo()
2676 ? New->getTypeSourceInfo()->getType()->castAs<FunctionType>()
2677 : NewType)->getReturnType();
2679 if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType) &&
2680 !((NewQType->isDependentType() || OldQType->isDependentType()) &&
2681 New->isLocalExternDecl())) {
2682 if (NewDeclaredReturnType->isObjCObjectPointerType() &&
2683 OldDeclaredReturnType->isObjCObjectPointerType())
2684 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType);
2685 if (ResQT.isNull()) {
2686 if (New->isCXXClassMember() && New->isOutOfLine())
2687 Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type)
2688 << New << New->getReturnTypeSourceRange();
2690 Diag(New->getLocation(), diag::err_ovl_diff_return_type)
2691 << New->getReturnTypeSourceRange();
2692 Diag(OldLocation, PrevDiag) << Old << Old->getType()
2693 << Old->getReturnTypeSourceRange();
2700 QualType OldReturnType = OldType->getReturnType();
2701 QualType NewReturnType = cast<FunctionType>(NewQType)->getReturnType();
2702 if (OldReturnType != NewReturnType) {
2703 // If this function has a deduced return type and has already been
2704 // defined, copy the deduced value from the old declaration.
2705 AutoType *OldAT = Old->getReturnType()->getContainedAutoType();
2706 if (OldAT && OldAT->isDeduced()) {
2708 SubstAutoType(New->getType(),
2709 OldAT->isDependentType() ? Context.DependentTy
2710 : OldAT->getDeducedType()));
2711 NewQType = Context.getCanonicalType(
2712 SubstAutoType(NewQType,
2713 OldAT->isDependentType() ? Context.DependentTy
2714 : OldAT->getDeducedType()));
2718 const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
2719 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
2720 if (OldMethod && NewMethod) {
2721 // Preserve triviality.
2722 NewMethod->setTrivial(OldMethod->isTrivial());
2724 // MSVC allows explicit template specialization at class scope:
2725 // 2 CXXMethodDecls referring to the same function will be injected.
2726 // We don't want a redeclaration error.
2727 bool IsClassScopeExplicitSpecialization =
2728 OldMethod->isFunctionTemplateSpecialization() &&
2729 NewMethod->isFunctionTemplateSpecialization();
2730 bool isFriend = NewMethod->getFriendObjectKind();
2732 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() &&
2733 !IsClassScopeExplicitSpecialization) {
2734 // -- Member function declarations with the same name and the
2735 // same parameter types cannot be overloaded if any of them
2736 // is a static member function declaration.
2737 if (OldMethod->isStatic() != NewMethod->isStatic()) {
2738 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
2739 Diag(OldLocation, PrevDiag) << Old << Old->getType();
2743 // C++ [class.mem]p1:
2744 // [...] A member shall not be declared twice in the
2745 // member-specification, except that a nested class or member
2746 // class template can be declared and then later defined.
2747 if (ActiveTemplateInstantiations.empty()) {
2749 if (isa<CXXConstructorDecl>(OldMethod))
2750 NewDiag = diag::err_constructor_redeclared;
2751 else if (isa<CXXDestructorDecl>(NewMethod))
2752 NewDiag = diag::err_destructor_redeclared;
2753 else if (isa<CXXConversionDecl>(NewMethod))
2754 NewDiag = diag::err_conv_function_redeclared;
2756 NewDiag = diag::err_member_redeclared;
2758 Diag(New->getLocation(), NewDiag);
2760 Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation)
2761 << New << New->getType();
2763 Diag(OldLocation, PrevDiag) << Old << Old->getType();
2765 // Complain if this is an explicit declaration of a special
2766 // member that was initially declared implicitly.
2768 // As an exception, it's okay to befriend such methods in order
2769 // to permit the implicit constructor/destructor/operator calls.
2770 } else if (OldMethod->isImplicit()) {
2772 NewMethod->setImplicit();
2774 Diag(NewMethod->getLocation(),
2775 diag::err_definition_of_implicitly_declared_member)
2776 << New << getSpecialMember(OldMethod);
2779 } else if (OldMethod->isExplicitlyDefaulted() && !isFriend) {
2780 Diag(NewMethod->getLocation(),
2781 diag::err_definition_of_explicitly_defaulted_member)
2782 << getSpecialMember(OldMethod);
2787 // C++11 [dcl.attr.noreturn]p1:
2788 // The first declaration of a function shall specify the noreturn
2789 // attribute if any declaration of that function specifies the noreturn
2791 const CXX11NoReturnAttr *NRA = New->getAttr<CXX11NoReturnAttr>();
2792 if (NRA && !Old->hasAttr<CXX11NoReturnAttr>()) {
2793 Diag(NRA->getLocation(), diag::err_noreturn_missing_on_first_decl);
2794 Diag(Old->getFirstDecl()->getLocation(),
2795 diag::note_noreturn_missing_first_decl);
2798 // C++11 [dcl.attr.depend]p2:
2799 // The first declaration of a function shall specify the
2800 // carries_dependency attribute for its declarator-id if any declaration
2801 // of the function specifies the carries_dependency attribute.
2802 const CarriesDependencyAttr *CDA = New->getAttr<CarriesDependencyAttr>();
2803 if (CDA && !Old->hasAttr<CarriesDependencyAttr>()) {
2804 Diag(CDA->getLocation(),
2805 diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/;
2806 Diag(Old->getFirstDecl()->getLocation(),
2807 diag::note_carries_dependency_missing_first_decl) << 0/*Function*/;
2811 // All declarations for a function shall agree exactly in both the
2812 // return type and the parameter-type-list.
2813 // We also want to respect all the extended bits except noreturn.
2815 // noreturn should now match unless the old type info didn't have it.
2816 QualType OldQTypeForComparison = OldQType;
2817 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) {
2818 assert(OldQType == QualType(OldType, 0));
2819 const FunctionType *OldTypeForComparison
2820 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true));
2821 OldQTypeForComparison = QualType(OldTypeForComparison, 0);
2822 assert(OldQTypeForComparison.isCanonical());
2825 if (haveIncompatibleLanguageLinkages(Old, New)) {
2826 // As a special case, retain the language linkage from previous
2827 // declarations of a friend function as an extension.
2829 // This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC
2830 // and is useful because there's otherwise no way to specify language
2831 // linkage within class scope.
2833 // Check cautiously as the friend object kind isn't yet complete.
2834 if (New->getFriendObjectKind() != Decl::FOK_None) {
2835 Diag(New->getLocation(), diag::ext_retained_language_linkage) << New;
2836 Diag(OldLocation, PrevDiag);
2838 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
2839 Diag(OldLocation, PrevDiag);
2844 if (OldQTypeForComparison == NewQType)
2845 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
2847 if ((NewQType->isDependentType() || OldQType->isDependentType()) &&
2848 New->isLocalExternDecl()) {
2849 // It's OK if we couldn't merge types for a local function declaraton
2850 // if either the old or new type is dependent. We'll merge the types
2851 // when we instantiate the function.
2855 // Fall through for conflicting redeclarations and redefinitions.
2858 // C: Function types need to be compatible, not identical. This handles
2859 // duplicate function decls like "void f(int); void f(enum X);" properly.
2860 if (!getLangOpts().CPlusPlus &&
2861 Context.typesAreCompatible(OldQType, NewQType)) {
2862 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>();
2863 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>();
2864 const FunctionProtoType *OldProto = nullptr;
2865 if (MergeTypeWithOld && isa<FunctionNoProtoType>(NewFuncType) &&
2866 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) {
2867 // The old declaration provided a function prototype, but the
2868 // new declaration does not. Merge in the prototype.
2869 assert(!OldProto->hasExceptionSpec() && "Exception spec in C");
2870 SmallVector<QualType, 16> ParamTypes(OldProto->param_types());
2872 Context.getFunctionType(NewFuncType->getReturnType(), ParamTypes,
2873 OldProto->getExtProtoInfo());
2874 New->setType(NewQType);
2875 New->setHasInheritedPrototype();
2877 // Synthesize parameters with the same types.
2878 SmallVector<ParmVarDecl*, 16> Params;
2879 for (const auto &ParamType : OldProto->param_types()) {
2880 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(),
2881 SourceLocation(), nullptr,
2882 ParamType, /*TInfo=*/nullptr,
2884 Param->setScopeInfo(0, Params.size());
2885 Param->setImplicit();
2886 Params.push_back(Param);
2889 New->setParams(Params);
2892 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
2895 // GNU C permits a K&R definition to follow a prototype declaration
2896 // if the declared types of the parameters in the K&R definition
2897 // match the types in the prototype declaration, even when the
2898 // promoted types of the parameters from the K&R definition differ
2899 // from the types in the prototype. GCC then keeps the types from
2902 // If a variadic prototype is followed by a non-variadic K&R definition,
2903 // the K&R definition becomes variadic. This is sort of an edge case, but
2904 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and
2906 if (!getLangOpts().CPlusPlus &&
2907 Old->hasPrototype() && !New->hasPrototype() &&
2908 New->getType()->getAs<FunctionProtoType>() &&
2909 Old->getNumParams() == New->getNumParams()) {
2910 SmallVector<QualType, 16> ArgTypes;
2911 SmallVector<GNUCompatibleParamWarning, 16> Warnings;
2912 const FunctionProtoType *OldProto
2913 = Old->getType()->getAs<FunctionProtoType>();
2914 const FunctionProtoType *NewProto
2915 = New->getType()->getAs<FunctionProtoType>();
2917 // Determine whether this is the GNU C extension.
2918 QualType MergedReturn = Context.mergeTypes(OldProto->getReturnType(),
2919 NewProto->getReturnType());
2920 bool LooseCompatible = !MergedReturn.isNull();
2921 for (unsigned Idx = 0, End = Old->getNumParams();
2922 LooseCompatible && Idx != End; ++Idx) {
2923 ParmVarDecl *OldParm = Old->getParamDecl(Idx);
2924 ParmVarDecl *NewParm = New->getParamDecl(Idx);
2925 if (Context.typesAreCompatible(OldParm->getType(),
2926 NewProto->getParamType(Idx))) {
2927 ArgTypes.push_back(NewParm->getType());
2928 } else if (Context.typesAreCompatible(OldParm->getType(),
2930 /*CompareUnqualified=*/true)) {
2931 GNUCompatibleParamWarning Warn = { OldParm, NewParm,
2932 NewProto->getParamType(Idx) };
2933 Warnings.push_back(Warn);
2934 ArgTypes.push_back(NewParm->getType());
2936 LooseCompatible = false;
2939 if (LooseCompatible) {
2940 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) {
2941 Diag(Warnings[Warn].NewParm->getLocation(),
2942 diag::ext_param_promoted_not_compatible_with_prototype)
2943 << Warnings[Warn].PromotedType
2944 << Warnings[Warn].OldParm->getType();
2945 if (Warnings[Warn].OldParm->getLocation().isValid())
2946 Diag(Warnings[Warn].OldParm->getLocation(),
2947 diag::note_previous_declaration);
2950 if (MergeTypeWithOld)
2951 New->setType(Context.getFunctionType(MergedReturn, ArgTypes,
2952 OldProto->getExtProtoInfo()));
2953 return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
2956 // Fall through to diagnose conflicting types.
2959 // A function that has already been declared has been redeclared or
2960 // defined with a different type; show an appropriate diagnostic.
2962 // If the previous declaration was an implicitly-generated builtin
2963 // declaration, then at the very least we should use a specialized note.
2965 if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) {
2966 // If it's actually a library-defined builtin function like 'malloc'
2967 // or 'printf', just warn about the incompatible redeclaration.
2968 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) {
2969 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New;
2970 Diag(OldLocation, diag::note_previous_builtin_declaration)
2971 << Old << Old->getType();
2973 // If this is a global redeclaration, just forget hereafter
2974 // about the "builtin-ness" of the function.
2976 // Doing this for local extern declarations is problematic. If
2977 // the builtin declaration remains visible, a second invalid
2978 // local declaration will produce a hard error; if it doesn't
2979 // remain visible, a single bogus local redeclaration (which is
2980 // actually only a warning) could break all the downstream code.
2981 if (!New->getLexicalDeclContext()->isFunctionOrMethod())
2982 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin);
2987 PrevDiag = diag::note_previous_builtin_declaration;
2990 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName();
2991 Diag(OldLocation, PrevDiag) << Old << Old->getType();
2995 /// \brief Completes the merge of two function declarations that are
2996 /// known to be compatible.
2998 /// This routine handles the merging of attributes and other
2999 /// properties of function declarations from the old declaration to
3000 /// the new declaration, once we know that New is in fact a
3001 /// redeclaration of Old.
3004 bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
3005 Scope *S, bool MergeTypeWithOld) {
3006 // Merge the attributes
3007 mergeDeclAttributes(New, Old);
3009 // Merge "pure" flag.
3013 // Merge "used" flag.
3014 if (Old->getMostRecentDecl()->isUsed(false))
3017 // Merge attributes from the parameters. These can mismatch with K&R
3019 if (New->getNumParams() == Old->getNumParams())
3020 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i)
3021 mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i),
3024 if (getLangOpts().CPlusPlus)
3025 return MergeCXXFunctionDecl(New, Old, S);
3027 // Merge the function types so the we get the composite types for the return
3028 // and argument types. Per C11 6.2.7/4, only update the type if the old decl
3030 QualType Merged = Context.mergeTypes(Old->getType(), New->getType());
3031 if (!Merged.isNull() && MergeTypeWithOld)
3032 New->setType(Merged);
3038 void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod,
3039 ObjCMethodDecl *oldMethod) {
3041 // Merge the attributes, including deprecated/unavailable
3042 AvailabilityMergeKind MergeKind =
3043 isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration
3045 mergeDeclAttributes(newMethod, oldMethod, MergeKind);
3047 // Merge attributes from the parameters.
3048 ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(),
3049 oe = oldMethod->param_end();
3050 for (ObjCMethodDecl::param_iterator
3051 ni = newMethod->param_begin(), ne = newMethod->param_end();
3052 ni != ne && oi != oe; ++ni, ++oi)
3053 mergeParamDeclAttributes(*ni, *oi, *this);
3055 CheckObjCMethodOverride(newMethod, oldMethod);
3058 /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and
3059 /// scope as a previous declaration 'Old'. Figure out how to merge their types,
3060 /// emitting diagnostics as appropriate.
3062 /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back
3063 /// to here in AddInitializerToDecl. We can't check them before the initializer
3065 void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old,
3066 bool MergeTypeWithOld) {
3067 if (New->isInvalidDecl() || Old->isInvalidDecl())
3071 if (getLangOpts().CPlusPlus) {
3072 if (New->getType()->isUndeducedType()) {
3073 // We don't know what the new type is until the initializer is attached.
3075 } else if (Context.hasSameType(New->getType(), Old->getType())) {
3076 // These could still be something that needs exception specs checked.
3077 return MergeVarDeclExceptionSpecs(New, Old);
3079 // C++ [basic.link]p10:
3080 // [...] the types specified by all declarations referring to a given
3081 // object or function shall be identical, except that declarations for an
3082 // array object can specify array types that differ by the presence or
3083 // absence of a major array bound (8.3.4).
3084 else if (Old->getType()->isIncompleteArrayType() &&
3085 New->getType()->isArrayType()) {
3086 const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
3087 const ArrayType *NewArray = Context.getAsArrayType(New->getType());
3088 if (Context.hasSameType(OldArray->getElementType(),
3089 NewArray->getElementType()))
3090 MergedT = New->getType();
3091 } else if (Old->getType()->isArrayType() &&
3092 New->getType()->isIncompleteArrayType()) {
3093 const ArrayType *OldArray = Context.getAsArrayType(Old->getType());
3094 const ArrayType *NewArray = Context.getAsArrayType(New->getType());
3095 if (Context.hasSameType(OldArray->getElementType(),
3096 NewArray->getElementType()))
3097 MergedT = Old->getType();
3098 } else if (New->getType()->isObjCObjectPointerType() &&
3099 Old->getType()->isObjCObjectPointerType()) {
3100 MergedT = Context.mergeObjCGCQualifiers(New->getType(),
3105 // All declarations that refer to the same object or function shall have
3107 MergedT = Context.mergeTypes(New->getType(), Old->getType());
3109 if (MergedT.isNull()) {
3110 // It's OK if we couldn't merge types if either type is dependent, for a
3111 // block-scope variable. In other cases (static data members of class
3112 // templates, variable templates, ...), we require the types to be
3114 // FIXME: The C++ standard doesn't say anything about this.
3115 if ((New->getType()->isDependentType() ||
3116 Old->getType()->isDependentType()) && New->isLocalVarDecl()) {
3117 // If the old type was dependent, we can't merge with it, so the new type
3118 // becomes dependent for now. We'll reproduce the original type when we
3119 // instantiate the TypeSourceInfo for the variable.
3120 if (!New->getType()->isDependentType() && MergeTypeWithOld)
3121 New->setType(Context.DependentTy);
3125 // FIXME: Even if this merging succeeds, some other non-visible declaration
3126 // of this variable might have an incompatible type. For instance:
3128 // extern int arr[];
3129 // void f() { extern int arr[2]; }
3130 // void g() { extern int arr[3]; }
3132 // Neither C nor C++ requires a diagnostic for this, but we should still try
3134 Diag(New->getLocation(), diag::err_redefinition_different_type)
3135 << New->getDeclName() << New->getType() << Old->getType();
3136 Diag(Old->getLocation(), diag::note_previous_definition);
3137 return New->setInvalidDecl();
3140 // Don't actually update the type on the new declaration if the old
3141 // declaration was an extern declaration in a different scope.
3142 if (MergeTypeWithOld)
3143 New->setType(MergedT);
3146 static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD,
3147 LookupResult &Previous) {
3149 // For an identifier with internal or external linkage declared
3150 // in a scope in which a prior declaration of that identifier is
3151 // visible, if the prior declaration specifies internal or
3152 // external linkage, the type of the identifier at the later
3153 // declaration becomes the composite type.
3155 // If the variable isn't visible, we do not merge with its type.
3156 if (Previous.isShadowed())
3159 if (S.getLangOpts().CPlusPlus) {
3160 // C++11 [dcl.array]p3:
3161 // If there is a preceding declaration of the entity in the same
3162 // scope in which the bound was specified, an omitted array bound
3163 // is taken to be the same as in that earlier declaration.
3164 return NewVD->isPreviousDeclInSameBlockScope() ||
3165 (!OldVD->getLexicalDeclContext()->isFunctionOrMethod() &&
3166 !NewVD->getLexicalDeclContext()->isFunctionOrMethod());
3168 // If the old declaration was function-local, don't merge with its
3169 // type unless we're in the same function.
3170 return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() ||
3171 OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext();
3175 /// MergeVarDecl - We just parsed a variable 'New' which has the same name
3176 /// and scope as a previous declaration 'Old'. Figure out how to resolve this
3177 /// situation, merging decls or emitting diagnostics as appropriate.
3179 /// Tentative definition rules (C99 6.9.2p2) are checked by
3180 /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative
3181 /// definitions here, since the initializer hasn't been attached.
3183 void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
3184 // If the new decl is already invalid, don't do any other checking.
3185 if (New->isInvalidDecl())
3188 VarTemplateDecl *NewTemplate = New->getDescribedVarTemplate();
3190 // Verify the old decl was also a variable or variable template.
3191 VarDecl *Old = nullptr;
3192 VarTemplateDecl *OldTemplate = nullptr;
3193 if (Previous.isSingleResult()) {
3195 OldTemplate = dyn_cast<VarTemplateDecl>(Previous.getFoundDecl());
3196 Old = OldTemplate ? OldTemplate->getTemplatedDecl() : nullptr;
3198 Old = dyn_cast<VarDecl>(Previous.getFoundDecl());
3201 Diag(New->getLocation(), diag::err_redefinition_different_kind)
3202 << New->getDeclName();
3203 Diag(Previous.getRepresentativeDecl()->getLocation(),
3204 diag::note_previous_definition);
3205 return New->setInvalidDecl();
3208 if (!shouldLinkPossiblyHiddenDecl(Old, New))
3211 // Ensure the template parameters are compatible.
3213 !TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
3214 OldTemplate->getTemplateParameters(),
3215 /*Complain=*/true, TPL_TemplateMatch))
3218 // C++ [class.mem]p1:
3219 // A member shall not be declared twice in the member-specification [...]
3221 // Here, we need only consider static data members.
3222 if (Old->isStaticDataMember() && !New->isOutOfLine()) {
3223 Diag(New->getLocation(), diag::err_duplicate_member)
3224 << New->getIdentifier();
3225 Diag(Old->getLocation(), diag::note_previous_declaration);
3226 New->setInvalidDecl();
3229 mergeDeclAttributes(New, Old);
3230 // Warn if an already-declared variable is made a weak_import in a subsequent
3232 if (New->hasAttr<WeakImportAttr>() &&
3233 Old->getStorageClass() == SC_None &&
3234 !Old->hasAttr<WeakImportAttr>()) {
3235 Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName();
3236 Diag(Old->getLocation(), diag::note_previous_definition);
3237 // Remove weak_import attribute on new declaration.
3238 New->dropAttr<WeakImportAttr>();
3242 VarDecl *MostRecent = Old->getMostRecentDecl();
3243 if (MostRecent != Old) {
3244 MergeVarDeclTypes(New, MostRecent,
3245 mergeTypeWithPrevious(*this, New, MostRecent, Previous));
3246 if (New->isInvalidDecl())
3250 MergeVarDeclTypes(New, Old, mergeTypeWithPrevious(*this, New, Old, Previous));
3251 if (New->isInvalidDecl())
3254 diag::kind PrevDiag;
3255 SourceLocation OldLocation;
3256 std::tie(PrevDiag, OldLocation) =
3257 getNoteDiagForInvalidRedeclaration(Old, New);
3259 // [dcl.stc]p8: Check if we have a non-static decl followed by a static.
3260 if (New->getStorageClass() == SC_Static &&
3261 !New->isStaticDataMember() &&
3262 Old->hasExternalFormalLinkage()) {
3263 if (getLangOpts().MicrosoftExt) {
3264 Diag(New->getLocation(), diag::ext_static_non_static)
3265 << New->getDeclName();
3266 Diag(OldLocation, PrevDiag);
3268 Diag(New->getLocation(), diag::err_static_non_static)
3269 << New->getDeclName();
3270 Diag(OldLocation, PrevDiag);
3271 return New->setInvalidDecl();
3275 // For an identifier declared with the storage-class specifier
3276 // extern in a scope in which a prior declaration of that
3277 // identifier is visible,23) if the prior declaration specifies
3278 // internal or external linkage, the linkage of the identifier at
3279 // the later declaration is the same as the linkage specified at
3280 // the prior declaration. If no prior declaration is visible, or
3281 // if the prior declaration specifies no linkage, then the
3282 // identifier has external linkage.
3283 if (New->hasExternalStorage() && Old->hasLinkage())
3285 else if (New->getCanonicalDecl()->getStorageClass() != SC_Static &&
3286 !New->isStaticDataMember() &&
3287 Old->getCanonicalDecl()->getStorageClass() == SC_Static) {
3288 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName();
3289 Diag(OldLocation, PrevDiag);
3290 return New->setInvalidDecl();
3293 // Check if extern is followed by non-extern and vice-versa.
3294 if (New->hasExternalStorage() &&
3295 !Old->hasLinkage() && Old->isLocalVarDeclOrParm()) {
3296 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName();
3297 Diag(OldLocation, PrevDiag);
3298 return New->setInvalidDecl();
3300 if (Old->hasLinkage() && New->isLocalVarDeclOrParm() &&
3301 !New->hasExternalStorage()) {
3302 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName();
3303 Diag(OldLocation, PrevDiag);
3304 return New->setInvalidDecl();
3307 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup.
3309 // FIXME: The test for external storage here seems wrong? We still
3310 // need to check for mismatches.
3311 if (!New->hasExternalStorage() && !New->isFileVarDecl() &&
3312 // Don't complain about out-of-line definitions of static members.
3313 !(Old->getLexicalDeclContext()->isRecord() &&
3314 !New->getLexicalDeclContext()->isRecord())) {
3315 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName();
3316 Diag(OldLocation, PrevDiag);
3317 return New->setInvalidDecl();
3320 if (New->getTLSKind() != Old->getTLSKind()) {
3321 if (!Old->getTLSKind()) {
3322 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName();
3323 Diag(OldLocation, PrevDiag);
3324 } else if (!New->getTLSKind()) {
3325 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName();
3326 Diag(OldLocation, PrevDiag);
3328 // Do not allow redeclaration to change the variable between requiring
3329 // static and dynamic initialization.
3330 // FIXME: GCC allows this, but uses the TLS keyword on the first
3331 // declaration to determine the kind. Do we need to be compatible here?
3332 Diag(New->getLocation(), diag::err_thread_thread_different_kind)
3333 << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic);
3334 Diag(OldLocation, PrevDiag);
3338 // C++ doesn't have tentative definitions, so go right ahead and check here.
3340 if (getLangOpts().CPlusPlus &&
3341 New->isThisDeclarationADefinition() == VarDecl::Definition &&
3342 (Def = Old->getDefinition())) {
3343 Diag(New->getLocation(), diag::err_redefinition) << New;
3344 Diag(Def->getLocation(), diag::note_previous_definition);
3345 New->setInvalidDecl();
3349 if (haveIncompatibleLanguageLinkages(Old, New)) {
3350 Diag(New->getLocation(), diag::err_different_language_linkage) << New;
3351 Diag(OldLocation, PrevDiag);
3352 New->setInvalidDecl();
3356 // Merge "used" flag.
3357 if (Old->getMostRecentDecl()->isUsed(false))
3360 // Keep a chain of previous declarations.
3361 New->setPreviousDecl(Old);
3363 NewTemplate->setPreviousDecl(OldTemplate);
3365 // Inherit access appropriately.
3366 New->setAccess(Old->getAccess());
3368 NewTemplate->setAccess(New->getAccess());
3371 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3372 /// no declarator (e.g. "struct foo;") is parsed.
3373 Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS,
3375 return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg());
3378 static void HandleTagNumbering(Sema &S, const TagDecl *Tag, Scope *TagScope) {
3379 if (!S.Context.getLangOpts().CPlusPlus)
3382 if (isa<CXXRecordDecl>(Tag->getParent())) {
3383 // If this tag is the direct child of a class, number it if
3385 if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl())
3387 MangleNumberingContext &MCtx =
3388 S.Context.getManglingNumberContext(Tag->getParent());
3389 S.Context.setManglingNumber(
3390 Tag, MCtx.getManglingNumber(Tag, TagScope->getMSLocalManglingNumber()));
3394 // If this tag isn't a direct child of a class, number it if it is local.
3395 Decl *ManglingContextDecl;
3396 if (MangleNumberingContext *MCtx =
3397 S.getCurrentMangleNumberContext(Tag->getDeclContext(),
3398 ManglingContextDecl)) {
3399 S.Context.setManglingNumber(
3401 MCtx->getManglingNumber(Tag, TagScope->getMSLocalManglingNumber()));
3405 /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
3406 /// no declarator (e.g. "struct foo;") is parsed. It also accepts template
3407 /// parameters to cope with template friend declarations.
3408 Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS,
3410 MultiTemplateParamsArg TemplateParams,
3411 bool IsExplicitInstantiation) {
3412 Decl *TagD = nullptr;
3413 TagDecl *Tag = nullptr;
3414 if (DS.getTypeSpecType() == DeclSpec::TST_class ||
3415 DS.getTypeSpecType() == DeclSpec::TST_struct ||
3416 DS.getTypeSpecType() == DeclSpec::TST_interface ||
3417 DS.getTypeSpecType() == DeclSpec::TST_union ||
3418 DS.getTypeSpecType() == DeclSpec::TST_enum) {
3419 TagD = DS.getRepAsDecl();
3421 if (!TagD) // We probably had an error
3424 // Note that the above type specs guarantee that the
3425 // type rep is a Decl, whereas in many of the others
3427 if (isa<TagDecl>(TagD))
3428 Tag = cast<TagDecl>(TagD);
3429 else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD))
3430 Tag = CTD->getTemplatedDecl();
3434 HandleTagNumbering(*this, Tag, S);
3435 Tag->setFreeStanding();
3436 if (Tag->isInvalidDecl())
3440 if (unsigned TypeQuals = DS.getTypeQualifiers()) {
3441 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object
3442 // or incomplete types shall not be restrict-qualified."
3443 if (TypeQuals & DeclSpec::TQ_restrict)
3444 Diag(DS.getRestrictSpecLoc(),
3445 diag::err_typecheck_invalid_restrict_not_pointer_noarg)
3446 << DS.getSourceRange();
3449 if (DS.isConstexprSpecified()) {
3450 // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations
3451 // and definitions of functions and variables.
3453 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag)
3454 << (DS.getTypeSpecType() == DeclSpec::TST_class ? 0 :
3455 DS.getTypeSpecType() == DeclSpec::TST_struct ? 1 :
3456 DS.getTypeSpecType() == DeclSpec::TST_interface ? 2 :
3457 DS.getTypeSpecType() == DeclSpec::TST_union ? 3 : 4);
3459 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_no_declarators);
3460 // Don't emit warnings after this error.
3464 DiagnoseFunctionSpecifiers(DS);
3466 if (DS.isFriendSpecified()) {
3467 // If we're dealing with a decl but not a TagDecl, assume that
3468 // whatever routines created it handled the friendship aspect.
3471 return ActOnFriendTypeDecl(S, DS, TemplateParams);
3474 CXXScopeSpec &SS = DS.getTypeSpecScope();
3475 bool IsExplicitSpecialization =
3476 !TemplateParams.empty() && TemplateParams.back()->size() == 0;
3477 if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() &&
3478 !IsExplicitInstantiation && !IsExplicitSpecialization) {
3479 // Per C++ [dcl.type.elab]p1, a class declaration cannot have a
3480 // nested-name-specifier unless it is an explicit instantiation
3481 // or an explicit specialization.
3482 // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either.
3483 Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier)
3484 << (DS.getTypeSpecType() == DeclSpec::TST_class ? 0 :
3485 DS.getTypeSpecType() == DeclSpec::TST_struct ? 1 :
3486 DS.getTypeSpecType() == DeclSpec::TST_interface ? 2 :
3487 DS.getTypeSpecType() == DeclSpec::TST_union ? 3 : 4)
3492 // Track whether this decl-specifier declares anything.
3493 bool DeclaresAnything = true;
3495 // Handle anonymous struct definitions.
3496 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
3497 if (!Record->getDeclName() && Record->isCompleteDefinition() &&
3498 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) {
3499 if (getLangOpts().CPlusPlus ||
3500 Record->getDeclContext()->isRecord())
3501 return BuildAnonymousStructOrUnion(S, DS, AS, Record, Context.getPrintingPolicy());
3503 DeclaresAnything = false;
3508 // A struct-declaration that does not declare an anonymous structure or
3509 // anonymous union shall contain a struct-declarator-list.
3511 // This rule also existed in C89 and C99; the grammar for struct-declaration
3512 // did not permit a struct-declaration without a struct-declarator-list.
3513 if (!getLangOpts().CPlusPlus && CurContext->isRecord() &&
3514 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) {
3515 // Check for Microsoft C extension: anonymous struct/union member.
3516 // Handle 2 kinds of anonymous struct/union:
3520 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct.
3521 // UNION_TYPE; <- where UNION_TYPE is a typedef union.
3522 if ((Tag && Tag->getDeclName()) ||
3523 DS.getTypeSpecType() == DeclSpec::TST_typename) {
3524 RecordDecl *Record = nullptr;
3526 Record = dyn_cast<RecordDecl>(Tag);
3527 else if (const RecordType *RT =
3528 DS.getRepAsType().get()->getAsStructureType())
3529 Record = RT->getDecl();
3530 else if (const RecordType *UT = DS.getRepAsType().get()->getAsUnionType())
3531 Record = UT->getDecl();
3533 if (Record && getLangOpts().MicrosoftExt) {
3534 Diag(DS.getLocStart(), diag::ext_ms_anonymous_record)
3535 << Record->isUnion() << DS.getSourceRange();
3536 return BuildMicrosoftCAnonymousStruct(S, DS, Record);
3539 DeclaresAnything = false;
3543 // Skip all the checks below if we have a type error.
3544 if (DS.getTypeSpecType() == DeclSpec::TST_error ||
3545 (TagD && TagD->isInvalidDecl()))
3548 if (getLangOpts().CPlusPlus &&
3549 DS.getStorageClassSpec() != DeclSpec::SCS_typedef)
3550 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag))
3551 if (Enum->enumerator_begin() == Enum->enumerator_end() &&
3552 !Enum->getIdentifier() && !Enum->isInvalidDecl())
3553 DeclaresAnything = false;
3555 if (!DS.isMissingDeclaratorOk()) {
3556 // Customize diagnostic for a typedef missing a name.
3557 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
3558 Diag(DS.getLocStart(), diag::ext_typedef_without_a_name)
3559 << DS.getSourceRange();
3561 DeclaresAnything = false;
3564 if (DS.isModulePrivateSpecified() &&
3565 Tag && Tag->getDeclContext()->isFunctionOrMethod())
3566 Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class)
3567 << Tag->getTagKind()
3568 << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc());
3570 ActOnDocumentableDecl(TagD);
3573 // A declaration [...] shall declare at least a declarator [...], a tag,
3574 // or the members of an enumeration.
3576 // [If there are no declarators], and except for the declaration of an
3577 // unnamed bit-field, the decl-specifier-seq shall introduce one or more
3578 // names into the program, or shall redeclare a name introduced by a
3579 // previous declaration.
3580 if (!DeclaresAnything) {
3581 // In C, we allow this as a (popular) extension / bug. Don't bother
3582 // producing further diagnostics for redundant qualifiers after this.
3583 Diag(DS.getLocStart(), diag::ext_no_declarators) << DS.getSourceRange();
3588 // If a storage-class-specifier appears in a decl-specifier-seq, [...] the
3589 // init-declarator-list of the declaration shall not be empty.
3590 // C++ [dcl.fct.spec]p1:
3591 // If a cv-qualifier appears in a decl-specifier-seq, the
3592 // init-declarator-list of the declaration shall not be empty.
3594 // Spurious qualifiers here appear to be valid in C.
3595 unsigned DiagID = diag::warn_standalone_specifier;
3596 if (getLangOpts().CPlusPlus)
3597 DiagID = diag::ext_standalone_specifier;
3599 // Note that a linkage-specification sets a storage class, but
3600 // 'extern "C" struct foo;' is actually valid and not theoretically
3602 if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
3603 if (SCS == DeclSpec::SCS_mutable)
3604 // Since mutable is not a viable storage class specifier in C, there is
3605 // no reason to treat it as an extension. Instead, diagnose as an error.
3606 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_nonmember);
3607 else if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef)
3608 Diag(DS.getStorageClassSpecLoc(), DiagID)
3609 << DeclSpec::getSpecifierName(SCS);
3612 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
3613 Diag(DS.getThreadStorageClassSpecLoc(), DiagID)
3614 << DeclSpec::getSpecifierName(TSCS);
3615 if (DS.getTypeQualifiers()) {
3616 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
3617 Diag(DS.getConstSpecLoc(), DiagID) << "const";
3618 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
3619 Diag(DS.getConstSpecLoc(), DiagID) << "volatile";
3620 // Restrict is covered above.
3621 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
3622 Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic";
3625 // Warn about ignored type attributes, for example:
3626 // __attribute__((aligned)) struct A;
3627 // Attributes should be placed after tag to apply to type declaration.
3628 if (!DS.getAttributes().empty()) {
3629 DeclSpec::TST TypeSpecType = DS.getTypeSpecType();
3630 if (TypeSpecType == DeclSpec::TST_class ||
3631 TypeSpecType == DeclSpec::TST_struct ||
3632 TypeSpecType == DeclSpec::TST_interface ||
3633 TypeSpecType == DeclSpec::TST_union ||
3634 TypeSpecType == DeclSpec::TST_enum) {
3635 AttributeList* attrs = DS.getAttributes().getList();
3637 Diag(attrs->getLoc(), diag::warn_declspec_attribute_ignored)
3639 << (TypeSpecType == DeclSpec::TST_class ? 0 :
3640 TypeSpecType == DeclSpec::TST_struct ? 1 :
3641 TypeSpecType == DeclSpec::TST_union ? 2 :
3642 TypeSpecType == DeclSpec::TST_interface ? 3 : 4);
3643 attrs = attrs->getNext();
3651 /// We are trying to inject an anonymous member into the given scope;
3652 /// check if there's an existing declaration that can't be overloaded.
3654 /// \return true if this is a forbidden redeclaration
3655 static bool CheckAnonMemberRedeclaration(Sema &SemaRef,
3658 DeclarationName Name,
3659 SourceLocation NameLoc,
3660 unsigned diagnostic) {
3661 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName,
3662 Sema::ForRedeclaration);
3663 if (!SemaRef.LookupName(R, S)) return false;
3665 if (R.getAsSingle<TagDecl>())
3668 // Pick a representative declaration.
3669 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl();
3670 assert(PrevDecl && "Expected a non-null Decl");
3672 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S))
3675 SemaRef.Diag(NameLoc, diagnostic) << Name;
3676 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
3681 /// InjectAnonymousStructOrUnionMembers - Inject the members of the
3682 /// anonymous struct or union AnonRecord into the owning context Owner
3683 /// and scope S. This routine will be invoked just after we realize
3684 /// that an unnamed union or struct is actually an anonymous union or
3691 /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and
3692 /// // f into the surrounding scope.x
3695 /// This routine is recursive, injecting the names of nested anonymous
3696 /// structs/unions into the owning context and scope as well.
3697 static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S,
3699 RecordDecl *AnonRecord,
3701 SmallVectorImpl<NamedDecl *> &Chaining,
3702 bool MSAnonStruct) {
3704 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl
3705 : diag::err_anonymous_struct_member_redecl;
3707 bool Invalid = false;
3709 // Look every FieldDecl and IndirectFieldDecl with a name.
3710 for (auto *D : AnonRecord->decls()) {
3711 if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) &&
3712 cast<NamedDecl>(D)->getDeclName()) {
3713 ValueDecl *VD = cast<ValueDecl>(D);
3714 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(),
3715 VD->getLocation(), diagKind)) {
3716 // C++ [class.union]p2:
3717 // The names of the members of an anonymous union shall be
3718 // distinct from the names of any other entity in the
3719 // scope in which the anonymous union is declared.
3722 // C++ [class.union]p2:
3723 // For the purpose of name lookup, after the anonymous union
3724 // definition, the members of the anonymous union are
3725 // considered to have been defined in the scope in which the
3726 // anonymous union is declared.
3727 unsigned OldChainingSize = Chaining.size();
3728 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD))
3729 for (auto *PI : IF->chain())
3730 Chaining.push_back(PI);
3732 Chaining.push_back(VD);
3734 assert(Chaining.size() >= 2);
3735 NamedDecl **NamedChain =
3736 new (SemaRef.Context)NamedDecl*[Chaining.size()];
3737 for (unsigned i = 0; i < Chaining.size(); i++)
3738 NamedChain[i] = Chaining[i];
3740 IndirectFieldDecl *IndirectField = IndirectFieldDecl::Create(
3741 SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(),
3742 VD->getType(), NamedChain, Chaining.size());
3744 for (const auto *Attr : VD->attrs())
3745 IndirectField->addAttr(Attr->clone(SemaRef.Context));
3747 IndirectField->setAccess(AS);
3748 IndirectField->setImplicit();
3749 SemaRef.PushOnScopeChains(IndirectField, S);
3751 // That includes picking up the appropriate access specifier.
3752 if (AS != AS_none) IndirectField->setAccess(AS);
3754 Chaining.resize(OldChainingSize);
3762 /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to
3763 /// a VarDecl::StorageClass. Any error reporting is up to the caller:
3764 /// illegal input values are mapped to SC_None.
3766 StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) {
3767 DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec();
3768 assert(StorageClassSpec != DeclSpec::SCS_typedef &&
3769 "Parser allowed 'typedef' as storage class VarDecl.");
3770 switch (StorageClassSpec) {
3771 case DeclSpec::SCS_unspecified: return SC_None;
3772 case DeclSpec::SCS_extern:
3773 if (DS.isExternInLinkageSpec())
3776 case DeclSpec::SCS_static: return SC_Static;
3777 case DeclSpec::SCS_auto: return SC_Auto;
3778 case DeclSpec::SCS_register: return SC_Register;
3779 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
3780 // Illegal SCSs map to None: error reporting is up to the caller.
3781 case DeclSpec::SCS_mutable: // Fall through.
3782 case DeclSpec::SCS_typedef: return SC_None;
3784 llvm_unreachable("unknown storage class specifier");
3787 static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) {
3788 assert(Record->hasInClassInitializer());
3790 for (const auto *I : Record->decls()) {
3791 const auto *FD = dyn_cast<FieldDecl>(I);
3792 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
3793 FD = IFD->getAnonField();
3794 if (FD && FD->hasInClassInitializer())
3795 return FD->getLocation();
3798 llvm_unreachable("couldn't find in-class initializer");
3801 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
3802 SourceLocation DefaultInitLoc) {
3803 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
3806 S.Diag(DefaultInitLoc, diag::err_multiple_mem_union_initialization);
3807 S.Diag(findDefaultInitializer(Parent), diag::note_previous_initializer) << 0;
3810 static void checkDuplicateDefaultInit(Sema &S, CXXRecordDecl *Parent,
3811 CXXRecordDecl *AnonUnion) {
3812 if (!Parent->isUnion() || !Parent->hasInClassInitializer())
3815 checkDuplicateDefaultInit(S, Parent, findDefaultInitializer(AnonUnion));
3818 /// BuildAnonymousStructOrUnion - Handle the declaration of an
3819 /// anonymous structure or union. Anonymous unions are a C++ feature
3820 /// (C++ [class.union]) and a C11 feature; anonymous structures
3821 /// are a C11 feature and GNU C++ extension.
3822 Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
3825 const PrintingPolicy &Policy) {
3826 DeclContext *Owner = Record->getDeclContext();
3828 // Diagnose whether this anonymous struct/union is an extension.
3829 if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11)
3830 Diag(Record->getLocation(), diag::ext_anonymous_union);
3831 else if (!Record->isUnion() && getLangOpts().CPlusPlus)
3832 Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct);
3833 else if (!Record->isUnion() && !getLangOpts().C11)
3834 Diag(Record->getLocation(), diag::ext_c11_anonymous_struct);
3836 // C and C++ require different kinds of checks for anonymous
3838 bool Invalid = false;
3839 if (getLangOpts().CPlusPlus) {
3840 const char *PrevSpec = nullptr;
3842 if (Record->isUnion()) {
3843 // C++ [class.union]p6:
3844 // Anonymous unions declared in a named namespace or in the
3845 // global namespace shall be declared static.
3846 if (DS.getStorageClassSpec() != DeclSpec::SCS_static &&
3847 (isa<TranslationUnitDecl>(Owner) ||
3848 (isa<NamespaceDecl>(Owner) &&
3849 cast<NamespaceDecl>(Owner)->getDeclName()))) {
3850 Diag(Record->getLocation(), diag::err_anonymous_union_not_static)
3851 << FixItHint::CreateInsertion(Record->getLocation(), "static ");
3853 // Recover by adding 'static'.
3854 DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(),
3855 PrevSpec, DiagID, Policy);
3857 // C++ [class.union]p6:
3858 // A storage class is not allowed in a declaration of an
3859 // anonymous union in a class scope.
3860 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified &&
3861 isa<RecordDecl>(Owner)) {
3862 Diag(DS.getStorageClassSpecLoc(),
3863 diag::err_anonymous_union_with_storage_spec)
3864 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
3866 // Recover by removing the storage specifier.
3867 DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified,
3869 PrevSpec, DiagID, Context.getPrintingPolicy());
3873 // Ignore const/volatile/restrict qualifiers.
3874 if (DS.getTypeQualifiers()) {
3875 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
3876 Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified)
3877 << Record->isUnion() << "const"
3878 << FixItHint::CreateRemoval(DS.getConstSpecLoc());
3879 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
3880 Diag(DS.getVolatileSpecLoc(),
3881 diag::ext_anonymous_struct_union_qualified)
3882 << Record->isUnion() << "volatile"
3883 << FixItHint::CreateRemoval(DS.getVolatileSpecLoc());
3884 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
3885 Diag(DS.getRestrictSpecLoc(),
3886 diag::ext_anonymous_struct_union_qualified)
3887 << Record->isUnion() << "restrict"
3888 << FixItHint::CreateRemoval(DS.getRestrictSpecLoc());
3889 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
3890 Diag(DS.getAtomicSpecLoc(),
3891 diag::ext_anonymous_struct_union_qualified)
3892 << Record->isUnion() << "_Atomic"
3893 << FixItHint::CreateRemoval(DS.getAtomicSpecLoc());
3895 DS.ClearTypeQualifiers();
3898 // C++ [class.union]p2:
3899 // The member-specification of an anonymous union shall only
3900 // define non-static data members. [Note: nested types and
3901 // functions cannot be declared within an anonymous union. ]
3902 for (auto *Mem : Record->decls()) {
3903 if (auto *FD = dyn_cast<FieldDecl>(Mem)) {
3904 // C++ [class.union]p3:
3905 // An anonymous union shall not have private or protected
3906 // members (clause 11).
3907 assert(FD->getAccess() != AS_none);
3908 if (FD->getAccess() != AS_public) {
3909 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member)
3910 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected);
3914 // C++ [class.union]p1
3915 // An object of a class with a non-trivial constructor, a non-trivial
3916 // copy constructor, a non-trivial destructor, or a non-trivial copy
3917 // assignment operator cannot be a member of a union, nor can an
3918 // array of such objects.
3919 if (CheckNontrivialField(FD))
3921 } else if (Mem->isImplicit()) {
3922 // Any implicit members are fine.
3923 } else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) {
3924 // This is a type that showed up in an
3925 // elaborated-type-specifier inside the anonymous struct or
3926 // union, but which actually declares a type outside of the
3927 // anonymous struct or union. It's okay.
3928 } else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) {
3929 if (!MemRecord->isAnonymousStructOrUnion() &&
3930 MemRecord->getDeclName()) {
3931 // Visual C++ allows type definition in anonymous struct or union.
3932 if (getLangOpts().MicrosoftExt)
3933 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type)
3934 << (int)Record->isUnion();
3936 // This is a nested type declaration.
3937 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type)
3938 << (int)Record->isUnion();
3942 // This is an anonymous type definition within another anonymous type.
3943 // This is a popular extension, provided by Plan9, MSVC and GCC, but
3944 // not part of standard C++.
3945 Diag(MemRecord->getLocation(),
3946 diag::ext_anonymous_record_with_anonymous_type)
3947 << (int)Record->isUnion();
3949 } else if (isa<AccessSpecDecl>(Mem)) {
3950 // Any access specifier is fine.
3951 } else if (isa<StaticAssertDecl>(Mem)) {
3952 // In C++1z, static_assert declarations are also fine.
3954 // We have something that isn't a non-static data
3955 // member. Complain about it.
3956 unsigned DK = diag::err_anonymous_record_bad_member;
3957 if (isa<TypeDecl>(Mem))
3958 DK = diag::err_anonymous_record_with_type;
3959 else if (isa<FunctionDecl>(Mem))
3960 DK = diag::err_anonymous_record_with_function;
3961 else if (isa<VarDecl>(Mem))
3962 DK = diag::err_anonymous_record_with_static;
3964 // Visual C++ allows type definition in anonymous struct or union.
3965 if (getLangOpts().MicrosoftExt &&
3966 DK == diag::err_anonymous_record_with_type)
3967 Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type)
3968 << (int)Record->isUnion();
3970 Diag(Mem->getLocation(), DK)
3971 << (int)Record->isUnion();
3977 // C++11 [class.union]p8 (DR1460):
3978 // At most one variant member of a union may have a
3979 // brace-or-equal-initializer.
3980 if (cast<CXXRecordDecl>(Record)->hasInClassInitializer() &&
3982 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Owner),
3983 cast<CXXRecordDecl>(Record));
3986 if (!Record->isUnion() && !Owner->isRecord()) {
3987 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member)
3988 << (int)getLangOpts().CPlusPlus;
3992 // Mock up a declarator.
3993 Declarator Dc(DS, Declarator::MemberContext);
3994 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
3995 assert(TInfo && "couldn't build declarator info for anonymous struct/union");
3997 // Create a declaration for this anonymous struct/union.
3998 NamedDecl *Anon = nullptr;
3999 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) {
4000 Anon = FieldDecl::Create(Context, OwningClass,
4002 Record->getLocation(),
4003 /*IdentifierInfo=*/nullptr,
4004 Context.getTypeDeclType(Record),
4006 /*BitWidth=*/nullptr, /*Mutable=*/false,
4007 /*InitStyle=*/ICIS_NoInit);
4008 Anon->setAccess(AS);
4009 if (getLangOpts().CPlusPlus)
4010 FieldCollector->Add(cast<FieldDecl>(Anon));
4012 DeclSpec::SCS SCSpec = DS.getStorageClassSpec();
4013 StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS);
4014 if (SCSpec == DeclSpec::SCS_mutable) {
4015 // mutable can only appear on non-static class members, so it's always
4017 Diag(Record->getLocation(), diag::err_mutable_nonmember);
4022 Anon = VarDecl::Create(Context, Owner,
4024 Record->getLocation(), /*IdentifierInfo=*/nullptr,
4025 Context.getTypeDeclType(Record),
4028 // Default-initialize the implicit variable. This initialization will be
4029 // trivial in almost all cases, except if a union member has an in-class
4031 // union { int n = 0; };
4032 ActOnUninitializedDecl(Anon, /*TypeMayContainAuto=*/false);
4034 Anon->setImplicit();
4036 // Mark this as an anonymous struct/union type.
4037 Record->setAnonymousStructOrUnion(true);
4039 // Add the anonymous struct/union object to the current
4040 // context. We'll be referencing this object when we refer to one of
4042 Owner->addDecl(Anon);
4044 // Inject the members of the anonymous struct/union into the owning
4045 // context and into the identifier resolver chain for name lookup
4047 SmallVector<NamedDecl*, 2> Chain;
4048 Chain.push_back(Anon);
4050 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS,
4054 if (VarDecl *NewVD = dyn_cast<VarDecl>(Anon)) {
4055 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
4056 Decl *ManglingContextDecl;
4057 if (MangleNumberingContext *MCtx =
4058 getCurrentMangleNumberContext(NewVD->getDeclContext(),
4059 ManglingContextDecl)) {
4060 Context.setManglingNumber(NewVD, MCtx->getManglingNumber(NewVD, S->getMSLocalManglingNumber()));
4061 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
4067 Anon->setInvalidDecl();
4072 /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an
4073 /// Microsoft C anonymous structure.
4074 /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx
4077 /// struct A { int a; };
4078 /// struct B { struct A; int b; };
4085 Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
4086 RecordDecl *Record) {
4087 assert(Record && "expected a record!");
4089 // Mock up a declarator.
4090 Declarator Dc(DS, Declarator::TypeNameContext);
4091 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
4092 assert(TInfo && "couldn't build declarator info for anonymous struct");
4094 auto *ParentDecl = cast<RecordDecl>(CurContext);
4095 QualType RecTy = Context.getTypeDeclType(Record);
4097 // Create a declaration for this anonymous struct.
4098 NamedDecl *Anon = FieldDecl::Create(Context,
4102 /*IdentifierInfo=*/nullptr,
4105 /*BitWidth=*/nullptr, /*Mutable=*/false,
4106 /*InitStyle=*/ICIS_NoInit);
4107 Anon->setImplicit();
4109 // Add the anonymous struct object to the current context.
4110 CurContext->addDecl(Anon);
4112 // Inject the members of the anonymous struct into the current
4113 // context and into the identifier resolver chain for name lookup
4115 SmallVector<NamedDecl*, 2> Chain;
4116 Chain.push_back(Anon);
4118 RecordDecl *RecordDef = Record->getDefinition();
4119 if (RequireCompleteType(Anon->getLocation(), RecTy,
4120 diag::err_field_incomplete) ||
4121 InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef,
4122 AS_none, Chain, true)) {
4123 Anon->setInvalidDecl();
4124 ParentDecl->setInvalidDecl();
4130 /// GetNameForDeclarator - Determine the full declaration name for the
4131 /// given Declarator.
4132 DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) {
4133 return GetNameFromUnqualifiedId(D.getName());
4136 /// \brief Retrieves the declaration name from a parsed unqualified-id.
4138 Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
4139 DeclarationNameInfo NameInfo;
4140 NameInfo.setLoc(Name.StartLocation);
4142 switch (Name.getKind()) {
4144 case UnqualifiedId::IK_ImplicitSelfParam:
4145 case UnqualifiedId::IK_Identifier:
4146 NameInfo.setName(Name.Identifier);
4147 NameInfo.setLoc(Name.StartLocation);
4150 case UnqualifiedId::IK_OperatorFunctionId:
4151 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName(
4152 Name.OperatorFunctionId.Operator));
4153 NameInfo.setLoc(Name.StartLocation);
4154 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc
4155 = Name.OperatorFunctionId.SymbolLocations[0];
4156 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc
4157 = Name.EndLocation.getRawEncoding();
4160 case UnqualifiedId::IK_LiteralOperatorId:
4161 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName(
4163 NameInfo.setLoc(Name.StartLocation);
4164 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation);
4167 case UnqualifiedId::IK_ConversionFunctionId: {
4168 TypeSourceInfo *TInfo;
4169 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo);
4171 return DeclarationNameInfo();
4172 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName(
4173 Context.getCanonicalType(Ty)));
4174 NameInfo.setLoc(Name.StartLocation);
4175 NameInfo.setNamedTypeInfo(TInfo);
4179 case UnqualifiedId::IK_ConstructorName: {
4180 TypeSourceInfo *TInfo;
4181 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo);
4183 return DeclarationNameInfo();
4184 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4185 Context.getCanonicalType(Ty)));
4186 NameInfo.setLoc(Name.StartLocation);
4187 NameInfo.setNamedTypeInfo(TInfo);
4191 case UnqualifiedId::IK_ConstructorTemplateId: {
4192 // In well-formed code, we can only have a constructor
4193 // template-id that refers to the current context, so go there
4194 // to find the actual type being constructed.
4195 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext);
4196 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name)
4197 return DeclarationNameInfo();
4199 // Determine the type of the class being constructed.
4200 QualType CurClassType = Context.getTypeDeclType(CurClass);
4202 // FIXME: Check two things: that the template-id names the same type as
4203 // CurClassType, and that the template-id does not occur when the name
4206 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
4207 Context.getCanonicalType(CurClassType)));
4208 NameInfo.setLoc(Name.StartLocation);
4209 // FIXME: should we retrieve TypeSourceInfo?
4210 NameInfo.setNamedTypeInfo(nullptr);
4214 case UnqualifiedId::IK_DestructorName: {
4215 TypeSourceInfo *TInfo;
4216 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo);
4218 return DeclarationNameInfo();
4219 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName(
4220 Context.getCanonicalType(Ty)));
4221 NameInfo.setLoc(Name.StartLocation);
4222 NameInfo.setNamedTypeInfo(TInfo);
4226 case UnqualifiedId::IK_TemplateId: {
4227 TemplateName TName = Name.TemplateId->Template.get();
4228 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc;
4229 return Context.getNameForTemplate(TName, TNameLoc);
4232 } // switch (Name.getKind())
4234 llvm_unreachable("Unknown name kind");
4237 static QualType getCoreType(QualType Ty) {
4239 if (Ty->isPointerType() || Ty->isReferenceType())
4240 Ty = Ty->getPointeeType();
4241 else if (Ty->isArrayType())
4242 Ty = Ty->castAsArrayTypeUnsafe()->getElementType();
4244 return Ty.withoutLocalFastQualifiers();
4248 /// hasSimilarParameters - Determine whether the C++ functions Declaration
4249 /// and Definition have "nearly" matching parameters. This heuristic is
4250 /// used to improve diagnostics in the case where an out-of-line function
4251 /// definition doesn't match any declaration within the class or namespace.
4252 /// Also sets Params to the list of indices to the parameters that differ
4253 /// between the declaration and the definition. If hasSimilarParameters
4254 /// returns true and Params is empty, then all of the parameters match.
4255 static bool hasSimilarParameters(ASTContext &Context,
4256 FunctionDecl *Declaration,
4257 FunctionDecl *Definition,
4258 SmallVectorImpl<unsigned> &Params) {
4260 if (Declaration->param_size() != Definition->param_size())
4262 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) {
4263 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType();
4264 QualType DefParamTy = Definition->getParamDecl(Idx)->getType();
4266 // The parameter types are identical
4267 if (Context.hasSameType(DefParamTy, DeclParamTy))
4270 QualType DeclParamBaseTy = getCoreType(DeclParamTy);
4271 QualType DefParamBaseTy = getCoreType(DefParamTy);
4272 const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier();
4273 const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier();
4275 if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) ||
4276 (DeclTyName && DeclTyName == DefTyName))
4277 Params.push_back(Idx);
4278 else // The two parameters aren't even close
4285 /// NeedsRebuildingInCurrentInstantiation - Checks whether the given
4286 /// declarator needs to be rebuilt in the current instantiation.
4287 /// Any bits of declarator which appear before the name are valid for
4288 /// consideration here. That's specifically the type in the decl spec
4289 /// and the base type in any member-pointer chunks.
4290 static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D,
4291 DeclarationName Name) {
4292 // The types we specifically need to rebuild are:
4293 // - typenames, typeofs, and decltypes
4294 // - types which will become injected class names
4295 // Of course, we also need to rebuild any type referencing such a
4296 // type. It's safest to just say "dependent", but we call out a
4299 DeclSpec &DS = D.getMutableDeclSpec();
4300 switch (DS.getTypeSpecType()) {
4301 case DeclSpec::TST_typename:
4302 case DeclSpec::TST_typeofType:
4303 case DeclSpec::TST_underlyingType:
4304 case DeclSpec::TST_atomic: {
4305 // Grab the type from the parser.
4306 TypeSourceInfo *TSI = nullptr;
4307 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI);
4308 if (T.isNull() || !T->isDependentType()) break;
4310 // Make sure there's a type source info. This isn't really much
4311 // of a waste; most dependent types should have type source info
4312 // attached already.
4314 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc());
4316 // Rebuild the type in the current instantiation.
4317 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name);
4318 if (!TSI) return true;
4320 // Store the new type back in the decl spec.
4321 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI);
4322 DS.UpdateTypeRep(LocType);
4326 case DeclSpec::TST_decltype:
4327 case DeclSpec::TST_typeofExpr: {
4328 Expr *E = DS.getRepAsExpr();
4329 ExprResult Result = S.RebuildExprInCurrentInstantiation(E);
4330 if (Result.isInvalid()) return true;
4331 DS.UpdateExprRep(Result.get());
4336 // Nothing to do for these decl specs.
4340 // It doesn't matter what order we do this in.
4341 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
4342 DeclaratorChunk &Chunk = D.getTypeObject(I);
4344 // The only type information in the declarator which can come
4345 // before the declaration name is the base type of a member
4347 if (Chunk.Kind != DeclaratorChunk::MemberPointer)
4350 // Rebuild the scope specifier in-place.
4351 CXXScopeSpec &SS = Chunk.Mem.Scope();
4352 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS))
4359 Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) {
4360 D.setFunctionDefinitionKind(FDK_Declaration);
4361 Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg());
4363 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() &&
4364 Dcl && Dcl->getDeclContext()->isFileContext())
4365 Dcl->setTopLevelDeclInObjCContainer();
4370 /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13:
4371 /// If T is the name of a class, then each of the following shall have a
4372 /// name different from T:
4373 /// - every static data member of class T;
4374 /// - every member function of class T
4375 /// - every member of class T that is itself a type;
4376 /// \returns true if the declaration name violates these rules.
4377 bool Sema::DiagnoseClassNameShadow(DeclContext *DC,
4378 DeclarationNameInfo NameInfo) {
4379 DeclarationName Name = NameInfo.getName();
4381 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
4382 if (Record->getIdentifier() && Record->getDeclName() == Name) {
4383 Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name;
4390 /// \brief Diagnose a declaration whose declarator-id has the given
4391 /// nested-name-specifier.
4393 /// \param SS The nested-name-specifier of the declarator-id.
4395 /// \param DC The declaration context to which the nested-name-specifier
4398 /// \param Name The name of the entity being declared.
4400 /// \param Loc The location of the name of the entity being declared.
4402 /// \returns true if we cannot safely recover from this error, false otherwise.
4403 bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
4404 DeclarationName Name,
4405 SourceLocation Loc) {
4406 DeclContext *Cur = CurContext;
4407 while (isa<LinkageSpecDecl>(Cur) || isa<CapturedDecl>(Cur))
4408 Cur = Cur->getParent();
4410 // If the user provided a superfluous scope specifier that refers back to the
4411 // class in which the entity is already declared, diagnose and ignore it.
4417 // Note, it was once ill-formed to give redundant qualification in all
4418 // contexts, but that rule was removed by DR482.
4419 if (Cur->Equals(DC)) {
4420 if (Cur->isRecord()) {
4421 Diag(Loc, LangOpts.MicrosoftExt ? diag::warn_member_extra_qualification
4422 : diag::err_member_extra_qualification)
4423 << Name << FixItHint::CreateRemoval(SS.getRange());
4426 Diag(Loc, diag::warn_namespace_member_extra_qualification) << Name;
4431 // Check whether the qualifying scope encloses the scope of the original
4433 if (!Cur->Encloses(DC)) {
4434 if (Cur->isRecord())
4435 Diag(Loc, diag::err_member_qualification)
4436 << Name << SS.getRange();
4437 else if (isa<TranslationUnitDecl>(DC))
4438 Diag(Loc, diag::err_invalid_declarator_global_scope)
4439 << Name << SS.getRange();
4440 else if (isa<FunctionDecl>(Cur))
4441 Diag(Loc, diag::err_invalid_declarator_in_function)
4442 << Name << SS.getRange();
4443 else if (isa<BlockDecl>(Cur))
4444 Diag(Loc, diag::err_invalid_declarator_in_block)
4445 << Name << SS.getRange();
4447 Diag(Loc, diag::err_invalid_declarator_scope)
4448 << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange();
4453 if (Cur->isRecord()) {
4454 // Cannot qualify members within a class.
4455 Diag(Loc, diag::err_member_qualification)
4456 << Name << SS.getRange();
4459 // C++ constructors and destructors with incorrect scopes can break
4460 // our AST invariants by having the wrong underlying types. If
4461 // that's the case, then drop this declaration entirely.
4462 if ((Name.getNameKind() == DeclarationName::CXXConstructorName ||
4463 Name.getNameKind() == DeclarationName::CXXDestructorName) &&
4464 !Context.hasSameType(Name.getCXXNameType(),
4465 Context.getTypeDeclType(cast<CXXRecordDecl>(Cur))))
4471 // C++11 [dcl.meaning]p1:
4472 // [...] "The nested-name-specifier of the qualified declarator-id shall
4473 // not begin with a decltype-specifer"
4474 NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data());
4475 while (SpecLoc.getPrefix())
4476 SpecLoc = SpecLoc.getPrefix();
4477 if (dyn_cast_or_null<DecltypeType>(
4478 SpecLoc.getNestedNameSpecifier()->getAsType()))
4479 Diag(Loc, diag::err_decltype_in_declarator)
4480 << SpecLoc.getTypeLoc().getSourceRange();
4485 NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
4486 MultiTemplateParamsArg TemplateParamLists) {
4487 // TODO: consider using NameInfo for diagnostic.
4488 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
4489 DeclarationName Name = NameInfo.getName();
4491 // All of these full declarators require an identifier. If it doesn't have
4492 // one, the ParsedFreeStandingDeclSpec action should be used.
4494 if (!D.isInvalidType()) // Reject this if we think it is valid.
4495 Diag(D.getDeclSpec().getLocStart(),
4496 diag::err_declarator_need_ident)
4497 << D.getDeclSpec().getSourceRange() << D.getSourceRange();
4499 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType))
4502 // The scope passed in may not be a decl scope. Zip up the scope tree until
4503 // we find one that is.
4504 while ((S->getFlags() & Scope::DeclScope) == 0 ||
4505 (S->getFlags() & Scope::TemplateParamScope) != 0)
4508 DeclContext *DC = CurContext;
4509 if (D.getCXXScopeSpec().isInvalid())
4511 else if (D.getCXXScopeSpec().isSet()) {
4512 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(),
4513 UPPC_DeclarationQualifier))
4516 bool EnteringContext = !D.getDeclSpec().isFriendSpecified();
4517 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext);
4518 if (!DC || isa<EnumDecl>(DC)) {
4519 // If we could not compute the declaration context, it's because the
4520 // declaration context is dependent but does not refer to a class,
4521 // class template, or class template partial specialization. Complain
4522 // and return early, to avoid the coming semantic disaster.
4523 Diag(D.getIdentifierLoc(),
4524 diag::err_template_qualified_declarator_no_match)
4525 << D.getCXXScopeSpec().getScopeRep()
4526 << D.getCXXScopeSpec().getRange();
4529 bool IsDependentContext = DC->isDependentContext();
4531 if (!IsDependentContext &&
4532 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC))
4535 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) {
4536 Diag(D.getIdentifierLoc(),
4537 diag::err_member_def_undefined_record)
4538 << Name << DC << D.getCXXScopeSpec().getRange();
4540 } else if (!D.getDeclSpec().isFriendSpecified()) {
4541 if (diagnoseQualifiedDeclaration(D.getCXXScopeSpec(), DC,
4542 Name, D.getIdentifierLoc())) {
4550 // Check whether we need to rebuild the type of the given
4551 // declaration in the current instantiation.
4552 if (EnteringContext && IsDependentContext &&
4553 TemplateParamLists.size() != 0) {
4554 ContextRAII SavedContext(*this, DC);
4555 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name))
4560 if (DiagnoseClassNameShadow(DC, NameInfo))
4561 // If this is a typedef, we'll end up spewing multiple diagnostics.
4562 // Just return early; it's safer.
4563 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
4566 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
4567 QualType R = TInfo->getType();
4569 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
4570 UPPC_DeclarationType))
4573 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
4576 // See if this is a redefinition of a variable in the same scope.
4577 if (!D.getCXXScopeSpec().isSet()) {
4578 bool IsLinkageLookup = false;
4579 bool CreateBuiltins = false;
4581 // If the declaration we're planning to build will be a function
4582 // or object with linkage, then look for another declaration with
4583 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6).
4585 // If the declaration we're planning to build will be declared with
4586 // external linkage in the translation unit, create any builtin with
4588 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
4590 else if (CurContext->isFunctionOrMethod() &&
4591 (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern ||
4592 R->isFunctionType())) {
4593 IsLinkageLookup = true;
4595 CurContext->getEnclosingNamespaceContext()->isTranslationUnit();
4596 } else if (CurContext->getRedeclContext()->isTranslationUnit() &&
4597 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)
4598 CreateBuiltins = true;
4600 if (IsLinkageLookup)
4601 Previous.clear(LookupRedeclarationWithLinkage);
4603 LookupName(Previous, S, CreateBuiltins);
4604 } else { // Something like "int foo::x;"
4605 LookupQualifiedName(Previous, DC);
4607 // C++ [dcl.meaning]p1:
4608 // When the declarator-id is qualified, the declaration shall refer to a
4609 // previously declared member of the class or namespace to which the
4610 // qualifier refers (or, in the case of a namespace, of an element of the
4611 // inline namespace set of that namespace (7.3.1)) or to a specialization
4614 // Note that we already checked the context above, and that we do not have
4615 // enough information to make sure that Previous contains the declaration
4616 // we want to match. For example, given:
4623 // void X::f(int) { } // ill-formed
4625 // In this case, Previous will point to the overload set
4626 // containing the two f's declared in X, but neither of them
4629 // C++ [dcl.meaning]p1:
4630 // [...] the member shall not merely have been introduced by a
4631 // using-declaration in the scope of the class or namespace nominated by
4632 // the nested-name-specifier of the declarator-id.
4633 RemoveUsingDecls(Previous);
4636 if (Previous.isSingleResult() &&
4637 Previous.getFoundDecl()->isTemplateParameter()) {
4638 // Maybe we will complain about the shadowed template parameter.
4639 if (!D.isInvalidType())
4640 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
4641 Previous.getFoundDecl());
4643 // Just pretend that we didn't see the previous declaration.
4647 // In C++, the previous declaration we find might be a tag type
4648 // (class or enum). In this case, the new declaration will hide the
4649 // tag type. Note that this does does not apply if we're declaring a
4650 // typedef (C++ [dcl.typedef]p4).
4651 if (Previous.isSingleTagDecl() &&
4652 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef)
4655 // Check that there are no default arguments other than in the parameters
4656 // of a function declaration (C++ only).
4657 if (getLangOpts().CPlusPlus)
4658 CheckExtraCXXDefaultArguments(D);
4662 bool AddToScope = true;
4663 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) {
4664 if (TemplateParamLists.size()) {
4665 Diag(D.getIdentifierLoc(), diag::err_template_typedef);
4669 New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous);
4670 } else if (R->isFunctionType()) {
4671 New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous,
4675 New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists,
4682 // If this has an identifier and is not an invalid redeclaration or
4683 // function template specialization, add it to the scope stack.
4684 if (New->getDeclName() && AddToScope &&
4685 !(D.isRedeclaration() && New->isInvalidDecl())) {
4686 // Only make a locally-scoped extern declaration visible if it is the first
4687 // declaration of this entity. Qualified lookup for such an entity should
4688 // only find this declaration if there is no visible declaration of it.
4689 bool AddToContext = !D.isRedeclaration() || !New->isLocalExternDecl();
4690 PushOnScopeChains(New, S, AddToContext);
4692 CurContext->addHiddenDecl(New);
4698 /// Helper method to turn variable array types into constant array
4699 /// types in certain situations which would otherwise be errors (for
4700 /// GCC compatibility).
4701 static QualType TryToFixInvalidVariablyModifiedType(QualType T,
4702 ASTContext &Context,
4703 bool &SizeIsNegative,
4704 llvm::APSInt &Oversized) {
4705 // This method tries to turn a variable array into a constant
4706 // array even when the size isn't an ICE. This is necessary
4707 // for compatibility with code that depends on gcc's buggy
4708 // constant expression folding, like struct {char x[(int)(char*)2];}
4709 SizeIsNegative = false;
4712 if (T->isDependentType())
4715 QualifierCollector Qs;
4716 const Type *Ty = Qs.strip(T);
4718 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) {
4719 QualType Pointee = PTy->getPointeeType();
4720 QualType FixedType =
4721 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative,
4723 if (FixedType.isNull()) return FixedType;
4724 FixedType = Context.getPointerType(FixedType);
4725 return Qs.apply(Context, FixedType);
4727 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) {
4728 QualType Inner = PTy->getInnerType();
4729 QualType FixedType =
4730 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative,
4732 if (FixedType.isNull()) return FixedType;
4733 FixedType = Context.getParenType(FixedType);
4734 return Qs.apply(Context, FixedType);
4737 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T);
4740 // FIXME: We should probably handle this case
4741 if (VLATy->getElementType()->isVariablyModifiedType())
4745 if (!VLATy->getSizeExpr() ||
4746 !VLATy->getSizeExpr()->EvaluateAsInt(Res, Context))
4749 // Check whether the array size is negative.
4750 if (Res.isSigned() && Res.isNegative()) {
4751 SizeIsNegative = true;
4755 // Check whether the array is too large to be addressed.
4756 unsigned ActiveSizeBits
4757 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(),
4759 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
4764 return Context.getConstantArrayType(VLATy->getElementType(),
4765 Res, ArrayType::Normal, 0);
4769 FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) {
4770 if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) {
4771 PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>();
4772 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(),
4773 DstPTL.getPointeeLoc());
4774 DstPTL.setStarLoc(SrcPTL.getStarLoc());
4777 if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) {
4778 ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>();
4779 FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(),
4780 DstPTL.getInnerLoc());
4781 DstPTL.setLParenLoc(SrcPTL.getLParenLoc());
4782 DstPTL.setRParenLoc(SrcPTL.getRParenLoc());
4785 ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>();
4786 ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>();
4787 TypeLoc SrcElemTL = SrcATL.getElementLoc();
4788 TypeLoc DstElemTL = DstATL.getElementLoc();
4789 DstElemTL.initializeFullCopy(SrcElemTL);
4790 DstATL.setLBracketLoc(SrcATL.getLBracketLoc());
4791 DstATL.setSizeExpr(SrcATL.getSizeExpr());
4792 DstATL.setRBracketLoc(SrcATL.getRBracketLoc());
4795 /// Helper method to turn variable array types into constant array
4796 /// types in certain situations which would otherwise be errors (for
4797 /// GCC compatibility).
4798 static TypeSourceInfo*
4799 TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo,
4800 ASTContext &Context,
4801 bool &SizeIsNegative,
4802 llvm::APSInt &Oversized) {
4804 = TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context,
4805 SizeIsNegative, Oversized);
4806 if (FixedTy.isNull())
4808 TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy);
4809 FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(),
4810 FixedTInfo->getTypeLoc());
4814 /// \brief Register the given locally-scoped extern "C" declaration so
4815 /// that it can be found later for redeclarations. We include any extern "C"
4816 /// declaration that is not visible in the translation unit here, not just
4817 /// function-scope declarations.
4819 Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) {
4820 if (!getLangOpts().CPlusPlus &&
4821 ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit())
4822 // Don't need to track declarations in the TU in C.
4825 // Note that we have a locally-scoped external with this name.
4826 // FIXME: There can be multiple such declarations if they are functions marked
4827 // __attribute__((overloadable)) declared in function scope in C.
4828 LocallyScopedExternCDecls[ND->getDeclName()] = ND;
4831 NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) {
4832 if (ExternalSource) {
4833 // Load locally-scoped external decls from the external source.
4834 // FIXME: This is inefficient. Maybe add a DeclContext for extern "C" decls?
4835 SmallVector<NamedDecl *, 4> Decls;
4836 ExternalSource->ReadLocallyScopedExternCDecls(Decls);
4837 for (unsigned I = 0, N = Decls.size(); I != N; ++I) {
4838 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos
4839 = LocallyScopedExternCDecls.find(Decls[I]->getDeclName());
4840 if (Pos == LocallyScopedExternCDecls.end())
4841 LocallyScopedExternCDecls[Decls[I]->getDeclName()] = Decls[I];
4845 NamedDecl *D = LocallyScopedExternCDecls.lookup(Name);
4846 return D ? D->getMostRecentDecl() : nullptr;
4849 /// \brief Diagnose function specifiers on a declaration of an identifier that
4850 /// does not identify a function.
4851 void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) {
4852 // FIXME: We should probably indicate the identifier in question to avoid
4853 // confusion for constructs like "inline int a(), b;"
4854 if (DS.isInlineSpecified())
4855 Diag(DS.getInlineSpecLoc(),
4856 diag::err_inline_non_function);
4858 if (DS.isVirtualSpecified())
4859 Diag(DS.getVirtualSpecLoc(),
4860 diag::err_virtual_non_function);
4862 if (DS.isExplicitSpecified())
4863 Diag(DS.getExplicitSpecLoc(),
4864 diag::err_explicit_non_function);
4866 if (DS.isNoreturnSpecified())
4867 Diag(DS.getNoreturnSpecLoc(),
4868 diag::err_noreturn_non_function);
4872 Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
4873 TypeSourceInfo *TInfo, LookupResult &Previous) {
4874 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1).
4875 if (D.getCXXScopeSpec().isSet()) {
4876 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator)
4877 << D.getCXXScopeSpec().getRange();
4879 // Pretend we didn't see the scope specifier.
4884 DiagnoseFunctionSpecifiers(D.getDeclSpec());
4886 if (D.getDeclSpec().isConstexprSpecified())
4887 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr)
4890 if (D.getName().Kind != UnqualifiedId::IK_Identifier) {
4891 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier)
4892 << D.getName().getSourceRange();
4896 TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo);
4897 if (!NewTD) return nullptr;
4899 // Handle attributes prior to checking for duplicates in MergeVarDecl
4900 ProcessDeclAttributes(S, NewTD, D);
4902 CheckTypedefForVariablyModifiedType(S, NewTD);
4904 bool Redeclaration = D.isRedeclaration();
4905 NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration);
4906 D.setRedeclaration(Redeclaration);
4911 Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) {
4912 // C99 6.7.7p2: If a typedef name specifies a variably modified type
4913 // then it shall have block scope.
4914 // Note that variably modified types must be fixed before merging the decl so
4915 // that redeclarations will match.
4916 TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo();
4917 QualType T = TInfo->getType();
4918 if (T->isVariablyModifiedType()) {
4919 getCurFunction()->setHasBranchProtectedScope();
4921 if (S->getFnParent() == nullptr) {
4922 bool SizeIsNegative;
4923 llvm::APSInt Oversized;
4924 TypeSourceInfo *FixedTInfo =
4925 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
4929 Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size);
4930 NewTD->setTypeSourceInfo(FixedTInfo);
4933 Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size);
4934 else if (T->isVariableArrayType())
4935 Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope);
4936 else if (Oversized.getBoolValue())
4937 Diag(NewTD->getLocation(), diag::err_array_too_large)
4938 << Oversized.toString(10);
4940 Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope);
4941 NewTD->setInvalidDecl();
4948 /// ActOnTypedefNameDecl - Perform semantic checking for a declaration which
4949 /// declares a typedef-name, either using the 'typedef' type specifier or via
4950 /// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'.
4952 Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD,
4953 LookupResult &Previous, bool &Redeclaration) {
4954 // Merge the decl with the existing one if appropriate. If the decl is
4955 // in an outer scope, it isn't the same thing.
4956 FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/false,
4957 /*AllowInlineNamespace*/false);
4958 filterNonConflictingPreviousTypedefDecls(Context, NewTD, Previous);
4959 if (!Previous.empty()) {
4960 Redeclaration = true;
4961 MergeTypedefNameDecl(NewTD, Previous);
4964 // If this is the C FILE type, notify the AST context.
4965 if (IdentifierInfo *II = NewTD->getIdentifier())
4966 if (!NewTD->isInvalidDecl() &&
4967 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
4968 if (II->isStr("FILE"))
4969 Context.setFILEDecl(NewTD);
4970 else if (II->isStr("jmp_buf"))
4971 Context.setjmp_bufDecl(NewTD);
4972 else if (II->isStr("sigjmp_buf"))
4973 Context.setsigjmp_bufDecl(NewTD);
4974 else if (II->isStr("ucontext_t"))
4975 Context.setucontext_tDecl(NewTD);
4981 /// \brief Determines whether the given declaration is an out-of-scope
4982 /// previous declaration.
4984 /// This routine should be invoked when name lookup has found a
4985 /// previous declaration (PrevDecl) that is not in the scope where a
4986 /// new declaration by the same name is being introduced. If the new
4987 /// declaration occurs in a local scope, previous declarations with
4988 /// linkage may still be considered previous declarations (C99
4989 /// 6.2.2p4-5, C++ [basic.link]p6).
4991 /// \param PrevDecl the previous declaration found by name
4994 /// \param DC the context in which the new declaration is being
4997 /// \returns true if PrevDecl is an out-of-scope previous declaration
4998 /// for a new delcaration with the same name.
5000 isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC,
5001 ASTContext &Context) {
5005 if (!PrevDecl->hasLinkage())
5008 if (Context.getLangOpts().CPlusPlus) {
5009 // C++ [basic.link]p6:
5010 // If there is a visible declaration of an entity with linkage
5011 // having the same name and type, ignoring entities declared
5012 // outside the innermost enclosing namespace scope, the block
5013 // scope declaration declares that same entity and receives the
5014 // linkage of the previous declaration.
5015 DeclContext *OuterContext = DC->getRedeclContext();
5016 if (!OuterContext->isFunctionOrMethod())
5017 // This rule only applies to block-scope declarations.
5020 DeclContext *PrevOuterContext = PrevDecl->getDeclContext();
5021 if (PrevOuterContext->isRecord())
5022 // We found a member function: ignore it.
5025 // Find the innermost enclosing namespace for the new and
5026 // previous declarations.
5027 OuterContext = OuterContext->getEnclosingNamespaceContext();
5028 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext();
5030 // The previous declaration is in a different namespace, so it
5031 // isn't the same function.
5032 if (!OuterContext->Equals(PrevOuterContext))
5039 static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) {
5040 CXXScopeSpec &SS = D.getCXXScopeSpec();
5041 if (!SS.isSet()) return;
5042 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext()));
5045 bool Sema::inferObjCARCLifetime(ValueDecl *decl) {
5046 QualType type = decl->getType();
5047 Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime();
5048 if (lifetime == Qualifiers::OCL_Autoreleasing) {
5049 // Various kinds of declaration aren't allowed to be __autoreleasing.
5050 unsigned kind = -1U;
5051 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5052 if (var->hasAttr<BlocksAttr>())
5053 kind = 0; // __block
5054 else if (!var->hasLocalStorage())
5056 } else if (isa<ObjCIvarDecl>(decl)) {
5058 } else if (isa<FieldDecl>(decl)) {
5063 Diag(decl->getLocation(), diag::err_arc_autoreleasing_var)
5066 } else if (lifetime == Qualifiers::OCL_None) {
5067 // Try to infer lifetime.
5068 if (!type->isObjCLifetimeType())
5071 lifetime = type->getObjCARCImplicitLifetime();
5072 type = Context.getLifetimeQualifiedType(type, lifetime);
5073 decl->setType(type);
5076 if (VarDecl *var = dyn_cast<VarDecl>(decl)) {
5077 // Thread-local variables cannot have lifetime.
5078 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone &&
5079 var->getTLSKind()) {
5080 Diag(var->getLocation(), diag::err_arc_thread_ownership)
5089 static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) {
5090 // Ensure that an auto decl is deduced otherwise the checks below might cache
5091 // the wrong linkage.
5092 assert(S.ParsingInitForAutoVars.count(&ND) == 0);
5094 // 'weak' only applies to declarations with external linkage.
5095 if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) {
5096 if (!ND.isExternallyVisible()) {
5097 S.Diag(Attr->getLocation(), diag::err_attribute_weak_static);
5098 ND.dropAttr<WeakAttr>();
5101 if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) {
5102 if (ND.isExternallyVisible()) {
5103 S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static);
5104 ND.dropAttr<WeakRefAttr>();
5108 // 'selectany' only applies to externally visible varable declarations.
5109 // It does not apply to functions.
5110 if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) {
5111 if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) {
5112 S.Diag(Attr->getLocation(), diag::err_attribute_selectany_non_extern_data);
5113 ND.dropAttr<SelectAnyAttr>();
5117 // dll attributes require external linkage.
5118 if (const InheritableAttr *Attr = getDLLAttr(&ND)) {
5119 if (!ND.isExternallyVisible()) {
5120 S.Diag(ND.getLocation(), diag::err_attribute_dll_not_extern)
5122 ND.setInvalidDecl();
5127 static void checkDLLAttributeRedeclaration(Sema &S, NamedDecl *OldDecl,
5129 bool IsSpecialization) {
5130 if (TemplateDecl *OldTD = dyn_cast<TemplateDecl>(OldDecl))
5131 OldDecl = OldTD->getTemplatedDecl();
5132 if (TemplateDecl *NewTD = dyn_cast<TemplateDecl>(NewDecl))
5133 NewDecl = NewTD->getTemplatedDecl();
5135 if (!OldDecl || !NewDecl)
5138 const DLLImportAttr *OldImportAttr = OldDecl->getAttr<DLLImportAttr>();
5139 const DLLExportAttr *OldExportAttr = OldDecl->getAttr<DLLExportAttr>();
5140 const DLLImportAttr *NewImportAttr = NewDecl->getAttr<DLLImportAttr>();
5141 const DLLExportAttr *NewExportAttr = NewDecl->getAttr<DLLExportAttr>();
5143 // dllimport and dllexport are inheritable attributes so we have to exclude
5144 // inherited attribute instances.
5145 bool HasNewAttr = (NewImportAttr && !NewImportAttr->isInherited()) ||
5146 (NewExportAttr && !NewExportAttr->isInherited());
5148 // A redeclaration is not allowed to add a dllimport or dllexport attribute,
5149 // the only exception being explicit specializations.
5150 // Implicitly generated declarations are also excluded for now because there
5151 // is no other way to switch these to use dllimport or dllexport.
5152 bool AddsAttr = !(OldImportAttr || OldExportAttr) && HasNewAttr;
5154 if (AddsAttr && !IsSpecialization && !OldDecl->isImplicit()) {
5155 // If the declaration hasn't been used yet, allow with a warning for
5156 // free functions and global variables.
5157 bool JustWarn = false;
5158 if (!OldDecl->isUsed() && !OldDecl->isCXXClassMember()) {
5159 auto *VD = dyn_cast<VarDecl>(OldDecl);
5160 if (VD && !VD->getDescribedVarTemplate())
5162 auto *FD = dyn_cast<FunctionDecl>(OldDecl);
5163 if (FD && FD->getTemplatedKind() == FunctionDecl::TK_NonTemplate)
5167 unsigned DiagID = JustWarn ? diag::warn_attribute_dll_redeclaration
5168 : diag::err_attribute_dll_redeclaration;
5169 S.Diag(NewDecl->getLocation(), DiagID)
5171 << (NewImportAttr ? (const Attr *)NewImportAttr : NewExportAttr);
5172 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5174 NewDecl->setInvalidDecl();
5179 // A redeclaration is not allowed to drop a dllimport attribute, the only
5180 // exceptions being inline function definitions, local extern declarations,
5181 // and qualified friend declarations.
5182 // NB: MSVC converts such a declaration to dllexport.
5183 bool IsInline = false, IsStaticDataMember = false, IsQualifiedFriend = false;
5184 if (const auto *VD = dyn_cast<VarDecl>(NewDecl))
5185 // Ignore static data because out-of-line definitions are diagnosed
5187 IsStaticDataMember = VD->isStaticDataMember();
5188 else if (const auto *FD = dyn_cast<FunctionDecl>(NewDecl)) {
5189 IsInline = FD->isInlined();
5190 IsQualifiedFriend = FD->getQualifier() &&
5191 FD->getFriendObjectKind() == Decl::FOK_Declared;
5194 if (OldImportAttr && !HasNewAttr && !IsInline && !IsStaticDataMember &&
5195 !NewDecl->isLocalExternDecl() && !IsQualifiedFriend) {
5196 S.Diag(NewDecl->getLocation(),
5197 diag::warn_redeclaration_without_attribute_prev_attribute_ignored)
5198 << NewDecl << OldImportAttr;
5199 S.Diag(OldDecl->getLocation(), diag::note_previous_declaration);
5200 S.Diag(OldImportAttr->getLocation(), diag::note_previous_attribute);
5201 OldDecl->dropAttr<DLLImportAttr>();
5202 NewDecl->dropAttr<DLLImportAttr>();
5203 } else if (IsInline && OldImportAttr &&
5204 !S.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
5205 // In MinGW, seeing a function declared inline drops the dllimport attribute.
5206 OldDecl->dropAttr<DLLImportAttr>();
5207 NewDecl->dropAttr<DLLImportAttr>();
5208 S.Diag(NewDecl->getLocation(),
5209 diag::warn_dllimport_dropped_from_inline_function)
5210 << NewDecl << OldImportAttr;
5214 /// Given that we are within the definition of the given function,
5215 /// will that definition behave like C99's 'inline', where the
5216 /// definition is discarded except for optimization purposes?
5217 static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) {
5218 // Try to avoid calling GetGVALinkageForFunction.
5220 // All cases of this require the 'inline' keyword.
5221 if (!FD->isInlined()) return false;
5223 // This is only possible in C++ with the gnu_inline attribute.
5224 if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>())
5227 // Okay, go ahead and call the relatively-more-expensive function.
5230 // AST quite reasonably asserts that it's working on a function
5231 // definition. We don't really have a way to tell it that we're
5232 // currently defining the function, so just lie to it in +Asserts
5233 // builds. This is an awful hack.
5238 S.Context.GetGVALinkageForFunction(FD) == GVA_AvailableExternally;
5247 /// Determine whether a variable is extern "C" prior to attaching
5248 /// an initializer. We can't just call isExternC() here, because that
5249 /// will also compute and cache whether the declaration is externally
5250 /// visible, which might change when we attach the initializer.
5252 /// This can only be used if the declaration is known to not be a
5253 /// redeclaration of an internal linkage declaration.
5259 /// Attaching the initializer here makes this declaration not externally
5260 /// visible, because its type has internal linkage.
5262 /// FIXME: This is a hack.
5263 template<typename T>
5264 static bool isIncompleteDeclExternC(Sema &S, const T *D) {
5265 if (S.getLangOpts().CPlusPlus) {
5266 // In C++, the overloadable attribute negates the effects of extern "C".
5267 if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>())
5270 return D->isExternC();
5273 static bool shouldConsiderLinkage(const VarDecl *VD) {
5274 const DeclContext *DC = VD->getDeclContext()->getRedeclContext();
5275 if (DC->isFunctionOrMethod())
5276 return VD->hasExternalStorage();
5277 if (DC->isFileContext())
5281 llvm_unreachable("Unexpected context");
5284 static bool shouldConsiderLinkage(const FunctionDecl *FD) {
5285 const DeclContext *DC = FD->getDeclContext()->getRedeclContext();
5286 if (DC->isFileContext() || DC->isFunctionOrMethod())
5290 llvm_unreachable("Unexpected context");
5293 static bool hasParsedAttr(Scope *S, const AttributeList *AttrList,
5294 AttributeList::Kind Kind) {
5295 for (const AttributeList *L = AttrList; L; L = L->getNext())
5296 if (L->getKind() == Kind)
5301 static bool hasParsedAttr(Scope *S, const Declarator &PD,
5302 AttributeList::Kind Kind) {
5303 // Check decl attributes on the DeclSpec.
5304 if (hasParsedAttr(S, PD.getDeclSpec().getAttributes().getList(), Kind))
5307 // Walk the declarator structure, checking decl attributes that were in a type
5308 // position to the decl itself.
5309 for (unsigned I = 0, E = PD.getNumTypeObjects(); I != E; ++I) {
5310 if (hasParsedAttr(S, PD.getTypeObject(I).getAttrs(), Kind))
5314 // Finally, check attributes on the decl itself.
5315 return hasParsedAttr(S, PD.getAttributes(), Kind);
5318 /// Adjust the \c DeclContext for a function or variable that might be a
5319 /// function-local external declaration.
5320 bool Sema::adjustContextForLocalExternDecl(DeclContext *&DC) {
5321 if (!DC->isFunctionOrMethod())
5324 // If this is a local extern function or variable declared within a function
5325 // template, don't add it into the enclosing namespace scope until it is
5326 // instantiated; it might have a dependent type right now.
5327 if (DC->isDependentContext())
5330 // C++11 [basic.link]p7:
5331 // When a block scope declaration of an entity with linkage is not found to
5332 // refer to some other declaration, then that entity is a member of the
5333 // innermost enclosing namespace.
5335 // Per C++11 [namespace.def]p6, the innermost enclosing namespace is a
5336 // semantically-enclosing namespace, not a lexically-enclosing one.
5337 while (!DC->isFileContext() && !isa<LinkageSpecDecl>(DC))
5338 DC = DC->getParent();
5343 Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC,
5344 TypeSourceInfo *TInfo, LookupResult &Previous,
5345 MultiTemplateParamsArg TemplateParamLists,
5347 QualType R = TInfo->getType();
5348 DeclarationName Name = GetNameForDeclarator(D).getName();
5350 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec();
5351 StorageClass SC = StorageClassSpecToVarDeclStorageClass(D.getDeclSpec());
5353 // dllimport globals without explicit storage class are treated as extern. We
5354 // have to change the storage class this early to get the right DeclContext.
5355 if (SC == SC_None && !DC->isRecord() &&
5356 hasParsedAttr(S, D, AttributeList::AT_DLLImport) &&
5357 !hasParsedAttr(S, D, AttributeList::AT_DLLExport))
5360 DeclContext *OriginalDC = DC;
5361 bool IsLocalExternDecl = SC == SC_Extern &&
5362 adjustContextForLocalExternDecl(DC);
5364 if (getLangOpts().OpenCL) {
5365 // OpenCL v1.0 s6.8.a.3: Pointers to functions are not allowed.
5367 while (NR->isPointerType()) {
5368 if (NR->isFunctionPointerType()) {
5369 Diag(D.getIdentifierLoc(), diag::err_opencl_function_pointer_variable);
5373 NR = NR->getPointeeType();
5376 if (!getOpenCLOptions().cl_khr_fp16) {
5377 // OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and
5378 // half array type (unless the cl_khr_fp16 extension is enabled).
5379 if (Context.getBaseElementType(R)->isHalfType()) {
5380 Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R;
5386 if (SCSpec == DeclSpec::SCS_mutable) {
5387 // mutable can only appear on non-static class members, so it's always
5389 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember);
5394 if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register &&
5395 !D.getAsmLabel() && !getSourceManager().isInSystemMacro(
5396 D.getDeclSpec().getStorageClassSpecLoc())) {
5397 // In C++11, the 'register' storage class specifier is deprecated.
5398 // Suppress the warning in system macros, it's used in macros in some
5399 // popular C system headers, such as in glibc's htonl() macro.
5400 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
5401 diag::warn_deprecated_register)
5402 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
5405 IdentifierInfo *II = Name.getAsIdentifierInfo();
5407 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name)
5412 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5414 if (!DC->isRecord() && S->getFnParent() == nullptr) {
5415 // C99 6.9p2: The storage-class specifiers auto and register shall not
5416 // appear in the declaration specifiers in an external declaration.
5417 // Global Register+Asm is a GNU extension we support.
5418 if (SC == SC_Auto || (SC == SC_Register && !D.getAsmLabel())) {
5419 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope);
5424 if (getLangOpts().OpenCL) {
5425 // Set up the special work-group-local storage class for variables in the
5426 // OpenCL __local address space.
5427 if (R.getAddressSpace() == LangAS::opencl_local) {
5428 SC = SC_OpenCLWorkGroupLocal;
5431 // OpenCL v1.2 s6.9.b p4:
5432 // The sampler type cannot be used with the __local and __global address
5433 // space qualifiers.
5434 if (R->isSamplerT() && (R.getAddressSpace() == LangAS::opencl_local ||
5435 R.getAddressSpace() == LangAS::opencl_global)) {
5436 Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace);
5439 // OpenCL 1.2 spec, p6.9 r:
5440 // The event type cannot be used to declare a program scope variable.
5441 // The event type cannot be used with the __local, __constant and __global
5442 // address space qualifiers.
5443 if (R->isEventT()) {
5444 if (S->getParent() == nullptr) {
5445 Diag(D.getLocStart(), diag::err_event_t_global_var);
5449 if (R.getAddressSpace()) {
5450 Diag(D.getLocStart(), diag::err_event_t_addr_space_qual);
5456 bool IsExplicitSpecialization = false;
5457 bool IsVariableTemplateSpecialization = false;
5458 bool IsPartialSpecialization = false;
5459 bool IsVariableTemplate = false;
5460 VarDecl *NewVD = nullptr;
5461 VarTemplateDecl *NewTemplate = nullptr;
5462 TemplateParameterList *TemplateParams = nullptr;
5463 if (!getLangOpts().CPlusPlus) {
5464 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
5465 D.getIdentifierLoc(), II,
5468 if (D.isInvalidType())
5469 NewVD->setInvalidDecl();
5471 bool Invalid = false;
5473 if (DC->isRecord() && !CurContext->isRecord()) {
5474 // This is an out-of-line definition of a static data member.
5479 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
5480 diag::err_static_out_of_line)
5481 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
5486 // [dcl.stc] p2: The auto or register specifiers shall be applied only
5487 // to names of variables declared in a block or to function parameters.
5488 // [dcl.stc] p6: The extern specifier cannot be used in the declaration
5491 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
5492 diag::err_storage_class_for_static_member)
5493 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
5495 case SC_PrivateExtern:
5496 llvm_unreachable("C storage class in c++!");
5497 case SC_OpenCLWorkGroupLocal:
5498 llvm_unreachable("OpenCL storage class in c++!");
5502 if (SC == SC_Static && CurContext->isRecord()) {
5503 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) {
5504 if (RD->isLocalClass())
5505 Diag(D.getIdentifierLoc(),
5506 diag::err_static_data_member_not_allowed_in_local_class)
5507 << Name << RD->getDeclName();
5509 // C++98 [class.union]p1: If a union contains a static data member,
5510 // the program is ill-formed. C++11 drops this restriction.
5512 Diag(D.getIdentifierLoc(),
5513 getLangOpts().CPlusPlus11
5514 ? diag::warn_cxx98_compat_static_data_member_in_union
5515 : diag::ext_static_data_member_in_union) << Name;
5516 // We conservatively disallow static data members in anonymous structs.
5517 else if (!RD->getDeclName())
5518 Diag(D.getIdentifierLoc(),
5519 diag::err_static_data_member_not_allowed_in_anon_struct)
5520 << Name << RD->isUnion();
5524 // Match up the template parameter lists with the scope specifier, then
5525 // determine whether we have a template or a template specialization.
5526 TemplateParams = MatchTemplateParametersToScopeSpecifier(
5527 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
5528 D.getCXXScopeSpec(),
5529 D.getName().getKind() == UnqualifiedId::IK_TemplateId
5530 ? D.getName().TemplateId
5533 /*never a friend*/ false, IsExplicitSpecialization, Invalid);
5535 if (TemplateParams) {
5536 if (!TemplateParams->size() &&
5537 D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
5538 // There is an extraneous 'template<>' for this variable. Complain
5539 // about it, but allow the declaration of the variable.
5540 Diag(TemplateParams->getTemplateLoc(),
5541 diag::err_template_variable_noparams)
5543 << SourceRange(TemplateParams->getTemplateLoc(),
5544 TemplateParams->getRAngleLoc());
5545 TemplateParams = nullptr;
5547 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
5548 // This is an explicit specialization or a partial specialization.
5549 // FIXME: Check that we can declare a specialization here.
5550 IsVariableTemplateSpecialization = true;
5551 IsPartialSpecialization = TemplateParams->size() > 0;
5552 } else { // if (TemplateParams->size() > 0)
5553 // This is a template declaration.
5554 IsVariableTemplate = true;
5556 // Check that we can declare a template here.
5557 if (CheckTemplateDeclScope(S, TemplateParams))
5560 // Only C++1y supports variable templates (N3651).
5561 Diag(D.getIdentifierLoc(),
5562 getLangOpts().CPlusPlus14
5563 ? diag::warn_cxx11_compat_variable_template
5564 : diag::ext_variable_template);
5568 assert(D.getName().getKind() != UnqualifiedId::IK_TemplateId &&
5569 "should have a 'template<>' for this decl");
5572 if (IsVariableTemplateSpecialization) {
5573 SourceLocation TemplateKWLoc =
5574 TemplateParamLists.size() > 0
5575 ? TemplateParamLists[0]->getTemplateLoc()
5577 DeclResult Res = ActOnVarTemplateSpecialization(
5578 S, D, TInfo, TemplateKWLoc, TemplateParams, SC,
5579 IsPartialSpecialization);
5580 if (Res.isInvalid())
5582 NewVD = cast<VarDecl>(Res.get());
5585 NewVD = VarDecl::Create(Context, DC, D.getLocStart(),
5586 D.getIdentifierLoc(), II, R, TInfo, SC);
5588 // If this is supposed to be a variable template, create it as such.
5589 if (IsVariableTemplate) {
5591 VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name,
5592 TemplateParams, NewVD);
5593 NewVD->setDescribedVarTemplate(NewTemplate);
5596 // If this decl has an auto type in need of deduction, make a note of the
5597 // Decl so we can diagnose uses of it in its own initializer.
5598 if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType())
5599 ParsingInitForAutoVars.insert(NewVD);
5601 if (D.isInvalidType() || Invalid) {
5602 NewVD->setInvalidDecl();
5604 NewTemplate->setInvalidDecl();
5607 SetNestedNameSpecifier(NewVD, D);
5609 // If we have any template parameter lists that don't directly belong to
5610 // the variable (matching the scope specifier), store them.
5611 unsigned VDTemplateParamLists = TemplateParams ? 1 : 0;
5612 if (TemplateParamLists.size() > VDTemplateParamLists)
5613 NewVD->setTemplateParameterListsInfo(
5614 Context, TemplateParamLists.size() - VDTemplateParamLists,
5615 TemplateParamLists.data());
5617 if (D.getDeclSpec().isConstexprSpecified())
5618 NewVD->setConstexpr(true);
5621 // Set the lexical context. If the declarator has a C++ scope specifier, the
5622 // lexical context will be different from the semantic context.
5623 NewVD->setLexicalDeclContext(CurContext);
5625 NewTemplate->setLexicalDeclContext(CurContext);
5627 if (IsLocalExternDecl)
5628 NewVD->setLocalExternDecl();
5630 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) {
5631 // C++11 [dcl.stc]p4:
5632 // When thread_local is applied to a variable of block scope the
5633 // storage-class-specifier static is implied if it does not appear
5635 // Core issue: 'static' is not implied if the variable is declared
5637 if (NewVD->hasLocalStorage() &&
5638 (SCSpec != DeclSpec::SCS_unspecified ||
5639 TSCS != DeclSpec::TSCS_thread_local ||
5640 !DC->isFunctionOrMethod()))
5641 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
5642 diag::err_thread_non_global)
5643 << DeclSpec::getSpecifierName(TSCS);
5644 else if (!Context.getTargetInfo().isTLSSupported())
5645 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
5646 diag::err_thread_unsupported);
5648 NewVD->setTSCSpec(TSCS);
5652 // An inline definition of a function with external linkage shall
5653 // not contain a definition of a modifiable object with static or
5654 // thread storage duration...
5655 // We only apply this when the function is required to be defined
5656 // elsewhere, i.e. when the function is not 'extern inline'. Note
5657 // that a local variable with thread storage duration still has to
5658 // be marked 'static'. Also note that it's possible to get these
5659 // semantics in C++ using __attribute__((gnu_inline)).
5660 if (SC == SC_Static && S->getFnParent() != nullptr &&
5661 !NewVD->getType().isConstQualified()) {
5662 FunctionDecl *CurFD = getCurFunctionDecl();
5663 if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) {
5664 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
5665 diag::warn_static_local_in_extern_inline);
5666 MaybeSuggestAddingStaticToDecl(CurFD);
5670 if (D.getDeclSpec().isModulePrivateSpecified()) {
5671 if (IsVariableTemplateSpecialization)
5672 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
5673 << (IsPartialSpecialization ? 1 : 0)
5674 << FixItHint::CreateRemoval(
5675 D.getDeclSpec().getModulePrivateSpecLoc());
5676 else if (IsExplicitSpecialization)
5677 Diag(NewVD->getLocation(), diag::err_module_private_specialization)
5679 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
5680 else if (NewVD->hasLocalStorage())
5681 Diag(NewVD->getLocation(), diag::err_module_private_local)
5682 << 0 << NewVD->getDeclName()
5683 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
5684 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
5686 NewVD->setModulePrivate();
5688 NewTemplate->setModulePrivate();
5692 // Handle attributes prior to checking for duplicates in MergeVarDecl
5693 ProcessDeclAttributes(S, NewVD, D);
5695 if (getLangOpts().CUDA) {
5696 // CUDA B.2.5: "__shared__ and __constant__ variables have implied static
5697 // storage [duration]."
5698 if (SC == SC_None && S->getFnParent() != nullptr &&
5699 (NewVD->hasAttr<CUDASharedAttr>() ||
5700 NewVD->hasAttr<CUDAConstantAttr>())) {
5701 NewVD->setStorageClass(SC_Static);
5705 // Ensure that dllimport globals without explicit storage class are treated as
5706 // extern. The storage class is set above using parsed attributes. Now we can
5707 // check the VarDecl itself.
5708 assert(!NewVD->hasAttr<DLLImportAttr>() ||
5709 NewVD->getAttr<DLLImportAttr>()->isInherited() ||
5710 NewVD->isStaticDataMember() || NewVD->getStorageClass() != SC_None);
5712 // In auto-retain/release, infer strong retension for variables of
5714 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD))
5715 NewVD->setInvalidDecl();
5717 // Handle GNU asm-label extension (encoded as an attribute).
5718 if (Expr *E = (Expr*)D.getAsmLabel()) {
5719 // The parser guarantees this is a string.
5720 StringLiteral *SE = cast<StringLiteral>(E);
5721 StringRef Label = SE->getString();
5722 if (S->getFnParent() != nullptr) {
5726 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label;
5729 // Local Named register
5730 if (!Context.getTargetInfo().isValidGCCRegisterName(Label))
5731 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
5735 case SC_PrivateExtern:
5736 case SC_OpenCLWorkGroupLocal:
5739 } else if (SC == SC_Register) {
5740 // Global Named register
5741 if (!Context.getTargetInfo().isValidGCCRegisterName(Label))
5742 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
5743 if (!R->isIntegralType(Context) && !R->isPointerType()) {
5744 Diag(D.getLocStart(), diag::err_asm_bad_register_type);
5745 NewVD->setInvalidDecl(true);
5749 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0),
5750 Context, Label, 0));
5751 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
5752 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
5753 ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier());
5754 if (I != ExtnameUndeclaredIdentifiers.end()) {
5755 NewVD->addAttr(I->second);
5756 ExtnameUndeclaredIdentifiers.erase(I);
5760 // Diagnose shadowed variables before filtering for scope.
5761 if (D.getCXXScopeSpec().isEmpty())
5762 CheckShadow(S, NewVD, Previous);
5764 // Don't consider existing declarations that are in a different
5765 // scope and are out-of-semantic-context declarations (if the new
5766 // declaration has linkage).
5767 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewVD),
5768 D.getCXXScopeSpec().isNotEmpty() ||
5769 IsExplicitSpecialization ||
5770 IsVariableTemplateSpecialization);
5772 // Check whether the previous declaration is in the same block scope. This
5773 // affects whether we merge types with it, per C++11 [dcl.array]p3.
5774 if (getLangOpts().CPlusPlus &&
5775 NewVD->isLocalVarDecl() && NewVD->hasExternalStorage())
5776 NewVD->setPreviousDeclInSameBlockScope(
5777 Previous.isSingleResult() && !Previous.isShadowed() &&
5778 isDeclInScope(Previous.getFoundDecl(), OriginalDC, S, false));
5780 if (!getLangOpts().CPlusPlus) {
5781 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
5783 // If this is an explicit specialization of a static data member, check it.
5784 if (IsExplicitSpecialization && !NewVD->isInvalidDecl() &&
5785 CheckMemberSpecialization(NewVD, Previous))
5786 NewVD->setInvalidDecl();
5788 // Merge the decl with the existing one if appropriate.
5789 if (!Previous.empty()) {
5790 if (Previous.isSingleResult() &&
5791 isa<FieldDecl>(Previous.getFoundDecl()) &&
5792 D.getCXXScopeSpec().isSet()) {
5793 // The user tried to define a non-static data member
5794 // out-of-line (C++ [dcl.meaning]p1).
5795 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line)
5796 << D.getCXXScopeSpec().getRange();
5798 NewVD->setInvalidDecl();
5800 } else if (D.getCXXScopeSpec().isSet()) {
5801 // No previous declaration in the qualifying scope.
5802 Diag(D.getIdentifierLoc(), diag::err_no_member)
5803 << Name << computeDeclContext(D.getCXXScopeSpec(), true)
5804 << D.getCXXScopeSpec().getRange();
5805 NewVD->setInvalidDecl();
5808 if (!IsVariableTemplateSpecialization)
5809 D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous));
5812 VarTemplateDecl *PrevVarTemplate =
5813 NewVD->getPreviousDecl()
5814 ? NewVD->getPreviousDecl()->getDescribedVarTemplate()
5817 // Check the template parameter list of this declaration, possibly
5818 // merging in the template parameter list from the previous variable
5819 // template declaration.
5820 if (CheckTemplateParameterList(
5822 PrevVarTemplate ? PrevVarTemplate->getTemplateParameters()
5824 (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() &&
5825 DC->isDependentContext())
5826 ? TPC_ClassTemplateMember
5828 NewVD->setInvalidDecl();
5830 // If we are providing an explicit specialization of a static variable
5831 // template, make a note of that.
5832 if (PrevVarTemplate &&
5833 PrevVarTemplate->getInstantiatedFromMemberTemplate())
5834 PrevVarTemplate->setMemberSpecialization();
5838 ProcessPragmaWeak(S, NewVD);
5840 // If this is the first declaration of an extern C variable, update
5841 // the map of such variables.
5842 if (NewVD->isFirstDecl() && !NewVD->isInvalidDecl() &&
5843 isIncompleteDeclExternC(*this, NewVD))
5844 RegisterLocallyScopedExternCDecl(NewVD, S);
5846 if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) {
5847 Decl *ManglingContextDecl;
5848 if (MangleNumberingContext *MCtx =
5849 getCurrentMangleNumberContext(NewVD->getDeclContext(),
5850 ManglingContextDecl)) {
5851 Context.setManglingNumber(
5852 NewVD, MCtx->getManglingNumber(NewVD, S->getMSLocalManglingNumber()));
5853 Context.setStaticLocalNumber(NewVD, MCtx->getStaticLocalNumber(NewVD));
5857 if (D.isRedeclaration() && !Previous.empty()) {
5858 checkDLLAttributeRedeclaration(
5859 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewVD,
5860 IsExplicitSpecialization);
5864 if (NewVD->isInvalidDecl())
5865 NewTemplate->setInvalidDecl();
5866 ActOnDocumentableDecl(NewTemplate);
5873 /// \brief Diagnose variable or built-in function shadowing. Implements
5876 /// This method is called whenever a VarDecl is added to a "useful"
5879 /// \param S the scope in which the shadowing name is being declared
5880 /// \param R the lookup of the name
5882 void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) {
5883 // Return if warning is ignored.
5884 if (Diags.isIgnored(diag::warn_decl_shadow, R.getNameLoc()))
5887 // Don't diagnose declarations at file scope.
5888 if (D->hasGlobalStorage())
5891 DeclContext *NewDC = D->getDeclContext();
5893 // Only diagnose if we're shadowing an unambiguous field or variable.
5894 if (R.getResultKind() != LookupResult::Found)
5897 NamedDecl* ShadowedDecl = R.getFoundDecl();
5898 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl))
5901 // Fields are not shadowed by variables in C++ static methods.
5902 if (isa<FieldDecl>(ShadowedDecl))
5903 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC))
5907 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl))
5908 if (shadowedVar->isExternC()) {
5909 // For shadowing external vars, make sure that we point to the global
5910 // declaration, not a locally scoped extern declaration.
5911 for (auto I : shadowedVar->redecls())
5912 if (I->isFileVarDecl()) {
5918 DeclContext *OldDC = ShadowedDecl->getDeclContext();
5920 // Only warn about certain kinds of shadowing for class members.
5921 if (NewDC && NewDC->isRecord()) {
5922 // In particular, don't warn about shadowing non-class members.
5923 if (!OldDC->isRecord())
5926 // TODO: should we warn about static data members shadowing
5927 // static data members from base classes?
5929 // TODO: don't diagnose for inaccessible shadowed members.
5930 // This is hard to do perfectly because we might friend the
5931 // shadowing context, but that's just a false negative.
5934 // Determine what kind of declaration we're shadowing.
5936 if (isa<RecordDecl>(OldDC)) {
5937 if (isa<FieldDecl>(ShadowedDecl))
5940 Kind = 2; // static data member
5941 } else if (OldDC->isFileContext())
5946 DeclarationName Name = R.getLookupName();
5948 // Emit warning and note.
5949 if (getSourceManager().isInSystemMacro(R.getNameLoc()))
5951 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC;
5952 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration);
5955 /// \brief Check -Wshadow without the advantage of a previous lookup.
5956 void Sema::CheckShadow(Scope *S, VarDecl *D) {
5957 if (Diags.isIgnored(diag::warn_decl_shadow, D->getLocation()))
5960 LookupResult R(*this, D->getDeclName(), D->getLocation(),
5961 Sema::LookupOrdinaryName, Sema::ForRedeclaration);
5963 CheckShadow(S, D, R);
5966 /// Check for conflict between this global or extern "C" declaration and
5967 /// previous global or extern "C" declarations. This is only used in C++.
5968 template<typename T>
5969 static bool checkGlobalOrExternCConflict(
5970 Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) {
5971 assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\"");
5972 NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName());
5974 if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) {
5975 // The common case: this global doesn't conflict with any extern "C"
5981 if (!IsGlobal || isIncompleteDeclExternC(S, ND)) {
5982 // Both the old and new declarations have C language linkage. This is a
5985 Previous.addDecl(Prev);
5989 // This is a global, non-extern "C" declaration, and there is a previous
5990 // non-global extern "C" declaration. Diagnose if this is a variable
5992 if (!isa<VarDecl>(ND))
5995 // The declaration is extern "C". Check for any declaration in the
5996 // translation unit which might conflict.
5998 // We have already performed the lookup into the translation unit.
6000 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6002 if (isa<VarDecl>(*I)) {
6008 DeclContext::lookup_result R =
6009 S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName());
6010 for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end();
6012 if (isa<VarDecl>(*I)) {
6016 // FIXME: If we have any other entity with this name in global scope,
6017 // the declaration is ill-formed, but that is a defect: it breaks the
6018 // 'stat' hack, for instance. Only variables can have mangled name
6019 // clashes with extern "C" declarations, so only they deserve a
6028 // Use the first declaration's location to ensure we point at something which
6029 // is lexically inside an extern "C" linkage-spec.
6030 assert(Prev && "should have found a previous declaration to diagnose");
6031 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev))
6032 Prev = FD->getFirstDecl();
6034 Prev = cast<VarDecl>(Prev)->getFirstDecl();
6036 S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict)
6038 S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict)
6043 /// Apply special rules for handling extern "C" declarations. Returns \c true
6044 /// if we have found that this is a redeclaration of some prior entity.
6046 /// Per C++ [dcl.link]p6:
6047 /// Two declarations [for a function or variable] with C language linkage
6048 /// with the same name that appear in different scopes refer to the same
6049 /// [entity]. An entity with C language linkage shall not be declared with
6050 /// the same name as an entity in global scope.
6051 template<typename T>
6052 static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND,
6053 LookupResult &Previous) {
6054 if (!S.getLangOpts().CPlusPlus) {
6055 // In C, when declaring a global variable, look for a corresponding 'extern'
6056 // variable declared in function scope. We don't need this in C++, because
6057 // we find local extern decls in the surrounding file-scope DeclContext.
6058 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
6059 if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) {
6061 Previous.addDecl(Prev);
6068 // A declaration in the translation unit can conflict with an extern "C"
6070 if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit())
6071 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous);
6073 // An extern "C" declaration can conflict with a declaration in the
6074 // translation unit or can be a redeclaration of an extern "C" declaration
6075 // in another scope.
6076 if (isIncompleteDeclExternC(S,ND))
6077 return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous);
6079 // Neither global nor extern "C": nothing to do.
6083 void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
6084 // If the decl is already known invalid, don't check it.
6085 if (NewVD->isInvalidDecl())
6088 TypeSourceInfo *TInfo = NewVD->getTypeSourceInfo();
6089 QualType T = TInfo->getType();
6091 // Defer checking an 'auto' type until its initializer is attached.
6092 if (T->isUndeducedType())
6095 if (NewVD->hasAttrs())
6096 CheckAlignasUnderalignment(NewVD);
6098 if (T->isObjCObjectType()) {
6099 Diag(NewVD->getLocation(), diag::err_statically_allocated_object)
6100 << FixItHint::CreateInsertion(NewVD->getLocation(), "*");
6101 T = Context.getObjCObjectPointerType(T);
6105 // Emit an error if an address space was applied to decl with local storage.
6106 // This includes arrays of objects with address space qualifiers, but not
6107 // automatic variables that point to other address spaces.
6108 // ISO/IEC TR 18037 S5.1.2
6109 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) {
6110 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl);
6111 NewVD->setInvalidDecl();
6115 // OpenCL v1.2 s6.5 - All program scope variables must be declared in the
6116 // __constant address space.
6117 if (getLangOpts().OpenCL && NewVD->isFileVarDecl()
6118 && T.getAddressSpace() != LangAS::opencl_constant
6119 && !T->isSamplerT()){
6120 Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space);
6121 NewVD->setInvalidDecl();
6125 // OpenCL v1.2 s6.8 -- The static qualifier is valid only in program
6127 if ((getLangOpts().OpenCLVersion >= 120)
6128 && NewVD->isStaticLocal()) {
6129 Diag(NewVD->getLocation(), diag::err_static_function_scope);
6130 NewVD->setInvalidDecl();
6134 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()
6135 && !NewVD->hasAttr<BlocksAttr>()) {
6136 if (getLangOpts().getGC() != LangOptions::NonGC)
6137 Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local);
6139 assert(!getLangOpts().ObjCAutoRefCount);
6140 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
6144 bool isVM = T->isVariablyModifiedType();
6145 if (isVM || NewVD->hasAttr<CleanupAttr>() ||
6146 NewVD->hasAttr<BlocksAttr>())
6147 getCurFunction()->setHasBranchProtectedScope();
6149 if ((isVM && NewVD->hasLinkage()) ||
6150 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) {
6151 bool SizeIsNegative;
6152 llvm::APSInt Oversized;
6153 TypeSourceInfo *FixedTInfo =
6154 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
6155 SizeIsNegative, Oversized);
6156 if (!FixedTInfo && T->isVariableArrayType()) {
6157 const VariableArrayType *VAT = Context.getAsVariableArrayType(T);
6158 // FIXME: This won't give the correct result for
6160 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange();
6162 if (NewVD->isFileVarDecl())
6163 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope)
6165 else if (NewVD->isStaticLocal())
6166 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage)
6169 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage)
6171 NewVD->setInvalidDecl();
6176 if (NewVD->isFileVarDecl())
6177 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope);
6179 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage);
6180 NewVD->setInvalidDecl();
6184 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size);
6185 NewVD->setType(FixedTInfo->getType());
6186 NewVD->setTypeSourceInfo(FixedTInfo);
6189 if (T->isVoidType()) {
6190 // C++98 [dcl.stc]p5: The extern specifier can be applied only to the names
6191 // of objects and functions.
6192 if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) {
6193 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type)
6195 NewVD->setInvalidDecl();
6200 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) {
6201 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal);
6202 NewVD->setInvalidDecl();
6206 if (isVM && NewVD->hasAttr<BlocksAttr>()) {
6207 Diag(NewVD->getLocation(), diag::err_block_on_vm);
6208 NewVD->setInvalidDecl();
6212 if (NewVD->isConstexpr() && !T->isDependentType() &&
6213 RequireLiteralType(NewVD->getLocation(), T,
6214 diag::err_constexpr_var_non_literal)) {
6215 NewVD->setInvalidDecl();
6220 /// \brief Perform semantic checking on a newly-created variable
6223 /// This routine performs all of the type-checking required for a
6224 /// variable declaration once it has been built. It is used both to
6225 /// check variables after they have been parsed and their declarators
6226 /// have been translated into a declaration, and to check variables
6227 /// that have been instantiated from a template.
6229 /// Sets NewVD->isInvalidDecl() if an error was encountered.
6231 /// Returns true if the variable declaration is a redeclaration.
6232 bool Sema::CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous) {
6233 CheckVariableDeclarationType(NewVD);
6235 // If the decl is already known invalid, don't check it.
6236 if (NewVD->isInvalidDecl())
6239 // If we did not find anything by this name, look for a non-visible
6240 // extern "C" declaration with the same name.
6241 if (Previous.empty() &&
6242 checkForConflictWithNonVisibleExternC(*this, NewVD, Previous))
6243 Previous.setShadowed();
6245 // Filter out any non-conflicting previous declarations.
6246 filterNonConflictingPreviousDecls(Context, NewVD, Previous);
6248 if (!Previous.empty()) {
6249 MergeVarDecl(NewVD, Previous);
6255 /// \brief Data used with FindOverriddenMethod
6256 struct FindOverriddenMethodData {
6258 CXXMethodDecl *Method;
6261 /// \brief Member lookup function that determines whether a given C++
6262 /// method overrides a method in a base class, to be used with
6263 /// CXXRecordDecl::lookupInBases().
6264 static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier,
6267 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();
6269 FindOverriddenMethodData *Data
6270 = reinterpret_cast<FindOverriddenMethodData*>(UserData);
6272 DeclarationName Name = Data->Method->getDeclName();
6274 // FIXME: Do we care about other names here too?
6275 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
6276 // We really want to find the base class destructor here.
6277 QualType T = Data->S->Context.getTypeDeclType(BaseRecord);
6278 CanQualType CT = Data->S->Context.getCanonicalType(T);
6280 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT);
6283 for (Path.Decls = BaseRecord->lookup(Name);
6284 !Path.Decls.empty();
6285 Path.Decls = Path.Decls.slice(1)) {
6286 NamedDecl *D = Path.Decls.front();
6287 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
6288 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false))
6297 enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted };
6299 /// \brief Report an error regarding overriding, along with any relevant
6300 /// overriden methods.
6302 /// \param DiagID the primary error to report.
6303 /// \param MD the overriding method.
6304 /// \param OEK which overrides to include as notes.
6305 static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD,
6306 OverrideErrorKind OEK = OEK_All) {
6307 S.Diag(MD->getLocation(), DiagID) << MD->getDeclName();
6308 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
6309 E = MD->end_overridden_methods();
6311 // This check (& the OEK parameter) could be replaced by a predicate, but
6312 // without lambdas that would be overkill. This is still nicer than writing
6313 // out the diag loop 3 times.
6314 if ((OEK == OEK_All) ||
6315 (OEK == OEK_NonDeleted && !(*I)->isDeleted()) ||
6316 (OEK == OEK_Deleted && (*I)->isDeleted()))
6317 S.Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
6321 /// AddOverriddenMethods - See if a method overrides any in the base classes,
6322 /// and if so, check that it's a valid override and remember it.
6323 bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) {
6324 // Look for methods in base classes that this method might override.
6326 FindOverriddenMethodData Data;
6329 bool hasDeletedOverridenMethods = false;
6330 bool hasNonDeletedOverridenMethods = false;
6331 bool AddedAny = false;
6332 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) {
6333 for (auto *I : Paths.found_decls()) {
6334 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(I)) {
6335 MD->addOverriddenMethod(OldMD->getCanonicalDecl());
6336 if (!CheckOverridingFunctionReturnType(MD, OldMD) &&
6337 !CheckOverridingFunctionAttributes(MD, OldMD) &&
6338 !CheckOverridingFunctionExceptionSpec(MD, OldMD) &&
6339 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) {
6340 hasDeletedOverridenMethods |= OldMD->isDeleted();
6341 hasNonDeletedOverridenMethods |= !OldMD->isDeleted();
6348 if (hasDeletedOverridenMethods && !MD->isDeleted()) {
6349 ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted);
6351 if (hasNonDeletedOverridenMethods && MD->isDeleted()) {
6352 ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted);
6359 // Struct for holding all of the extra arguments needed by
6360 // DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator.
6361 struct ActOnFDArgs {
6364 MultiTemplateParamsArg TemplateParamLists;
6371 // Callback to only accept typo corrections that have a non-zero edit distance.
6372 // Also only accept corrections that have the same parent decl.
6373 class DifferentNameValidatorCCC : public CorrectionCandidateCallback {
6375 DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD,
6376 CXXRecordDecl *Parent)
6377 : Context(Context), OriginalFD(TypoFD),
6378 ExpectedParent(Parent ? Parent->getCanonicalDecl() : nullptr) {}
6380 bool ValidateCandidate(const TypoCorrection &candidate) override {
6381 if (candidate.getEditDistance() == 0)
6384 SmallVector<unsigned, 1> MismatchedParams;
6385 for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(),
6386 CDeclEnd = candidate.end();
6387 CDecl != CDeclEnd; ++CDecl) {
6388 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
6390 if (FD && !FD->hasBody() &&
6391 hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) {
6392 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
6393 CXXRecordDecl *Parent = MD->getParent();
6394 if (Parent && Parent->getCanonicalDecl() == ExpectedParent)
6396 } else if (!ExpectedParent) {
6406 ASTContext &Context;
6407 FunctionDecl *OriginalFD;
6408 CXXRecordDecl *ExpectedParent;
6413 /// \brief Generate diagnostics for an invalid function redeclaration.
6415 /// This routine handles generating the diagnostic messages for an invalid
6416 /// function redeclaration, including finding possible similar declarations
6417 /// or performing typo correction if there are no previous declarations with
6420 /// Returns a NamedDecl iff typo correction was performed and substituting in
6421 /// the new declaration name does not cause new errors.
6422 static NamedDecl *DiagnoseInvalidRedeclaration(
6423 Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD,
6424 ActOnFDArgs &ExtraArgs, bool IsLocalFriend, Scope *S) {
6425 DeclarationName Name = NewFD->getDeclName();
6426 DeclContext *NewDC = NewFD->getDeclContext();
6427 SmallVector<unsigned, 1> MismatchedParams;
6428 SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches;
6429 TypoCorrection Correction;
6430 bool IsDefinition = ExtraArgs.D.isFunctionDefinition();
6431 unsigned DiagMsg = IsLocalFriend ? diag::err_no_matching_local_friend
6432 : diag::err_member_decl_does_not_match;
6433 LookupResult Prev(SemaRef, Name, NewFD->getLocation(),
6434 IsLocalFriend ? Sema::LookupLocalFriendName
6435 : Sema::LookupOrdinaryName,
6436 Sema::ForRedeclaration);
6438 NewFD->setInvalidDecl();
6440 SemaRef.LookupName(Prev, S);
6442 SemaRef.LookupQualifiedName(Prev, NewDC);
6443 assert(!Prev.isAmbiguous() &&
6444 "Cannot have an ambiguity in previous-declaration lookup");
6445 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
6446 if (!Prev.empty()) {
6447 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end();
6448 Func != FuncEnd; ++Func) {
6449 FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func);
6451 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
6452 // Add 1 to the index so that 0 can mean the mismatch didn't
6453 // involve a parameter
6455 MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1;
6456 NearMatches.push_back(std::make_pair(FD, ParamNum));
6459 // If the qualified name lookup yielded nothing, try typo correction
6460 } else if ((Correction = SemaRef.CorrectTypo(
6461 Prev.getLookupNameInfo(), Prev.getLookupKind(), S,
6462 &ExtraArgs.D.getCXXScopeSpec(),
6463 llvm::make_unique<DifferentNameValidatorCCC>(
6464 SemaRef.Context, NewFD, MD ? MD->getParent() : nullptr),
6465 Sema::CTK_ErrorRecovery, IsLocalFriend ? nullptr : NewDC))) {
6466 // Set up everything for the call to ActOnFunctionDeclarator
6467 ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(),
6468 ExtraArgs.D.getIdentifierLoc());
6470 Previous.setLookupName(Correction.getCorrection());
6471 for (TypoCorrection::decl_iterator CDecl = Correction.begin(),
6472 CDeclEnd = Correction.end();
6473 CDecl != CDeclEnd; ++CDecl) {
6474 FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl);
6475 if (FD && !FD->hasBody() &&
6476 hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) {
6477 Previous.addDecl(FD);
6480 bool wasRedeclaration = ExtraArgs.D.isRedeclaration();
6483 // Retry building the function declaration with the new previous
6484 // declarations, and with errors suppressed.
6487 Sema::SFINAETrap Trap(SemaRef);
6489 // TODO: Refactor ActOnFunctionDeclarator so that we can call only the
6490 // pieces need to verify the typo-corrected C++ declaration and hopefully
6491 // eliminate the need for the parameter pack ExtraArgs.
6492 Result = SemaRef.ActOnFunctionDeclarator(
6493 ExtraArgs.S, ExtraArgs.D,
6494 Correction.getCorrectionDecl()->getDeclContext(),
6495 NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists,
6496 ExtraArgs.AddToScope);
6498 if (Trap.hasErrorOccurred())
6503 // Determine which correction we picked.
6504 Decl *Canonical = Result->getCanonicalDecl();
6505 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
6507 if ((*I)->getCanonicalDecl() == Canonical)
6508 Correction.setCorrectionDecl(*I);
6510 SemaRef.diagnoseTypo(
6512 SemaRef.PDiag(IsLocalFriend
6513 ? diag::err_no_matching_local_friend_suggest
6514 : diag::err_member_decl_does_not_match_suggest)
6515 << Name << NewDC << IsDefinition);
6519 // Pretend the typo correction never occurred
6520 ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(),
6521 ExtraArgs.D.getIdentifierLoc());
6522 ExtraArgs.D.setRedeclaration(wasRedeclaration);
6524 Previous.setLookupName(Name);
6527 SemaRef.Diag(NewFD->getLocation(), DiagMsg)
6528 << Name << NewDC << IsDefinition << NewFD->getLocation();
6530 bool NewFDisConst = false;
6531 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD))
6532 NewFDisConst = NewMD->isConst();
6534 for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator
6535 NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end();
6536 NearMatch != NearMatchEnd; ++NearMatch) {
6537 FunctionDecl *FD = NearMatch->first;
6538 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
6539 bool FDisConst = MD && MD->isConst();
6540 bool IsMember = MD || !IsLocalFriend;
6542 // FIXME: These notes are poorly worded for the local friend case.
6543 if (unsigned Idx = NearMatch->second) {
6544 ParmVarDecl *FDParam = FD->getParamDecl(Idx-1);
6545 SourceLocation Loc = FDParam->getTypeSpecStartLoc();
6546 if (Loc.isInvalid()) Loc = FD->getLocation();
6547 SemaRef.Diag(Loc, IsMember ? diag::note_member_def_close_param_match
6548 : diag::note_local_decl_close_param_match)
6549 << Idx << FDParam->getType()
6550 << NewFD->getParamDecl(Idx - 1)->getType();
6551 } else if (FDisConst != NewFDisConst) {
6552 SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match)
6553 << NewFDisConst << FD->getSourceRange().getEnd();
6555 SemaRef.Diag(FD->getLocation(),
6556 IsMember ? diag::note_member_def_close_match
6557 : diag::note_local_decl_close_match);
6562 static StorageClass getFunctionStorageClass(Sema &SemaRef, Declarator &D) {
6563 switch (D.getDeclSpec().getStorageClassSpec()) {
6564 default: llvm_unreachable("Unknown storage class!");
6565 case DeclSpec::SCS_auto:
6566 case DeclSpec::SCS_register:
6567 case DeclSpec::SCS_mutable:
6568 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6569 diag::err_typecheck_sclass_func);
6572 case DeclSpec::SCS_unspecified: break;
6573 case DeclSpec::SCS_extern:
6574 if (D.getDeclSpec().isExternInLinkageSpec())
6577 case DeclSpec::SCS_static: {
6578 if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) {
6580 // The declaration of an identifier for a function that has
6581 // block scope shall have no explicit storage-class specifier
6582 // other than extern
6583 // See also (C++ [dcl.stc]p4).
6584 SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(),
6585 diag::err_static_block_func);
6590 case DeclSpec::SCS_private_extern: return SC_PrivateExtern;
6593 // No explicit storage class has already been returned
6597 static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D,
6598 DeclContext *DC, QualType &R,
6599 TypeSourceInfo *TInfo,
6601 bool &IsVirtualOkay) {
6602 DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D);
6603 DeclarationName Name = NameInfo.getName();
6605 FunctionDecl *NewFD = nullptr;
6606 bool isInline = D.getDeclSpec().isInlineSpecified();
6608 if (!SemaRef.getLangOpts().CPlusPlus) {
6609 // Determine whether the function was written with a
6610 // prototype. This true when:
6611 // - there is a prototype in the declarator, or
6612 // - the type R of the function is some kind of typedef or other reference
6613 // to a type name (which eventually refers to a function type).
6615 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) ||
6616 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType());
6618 NewFD = FunctionDecl::Create(SemaRef.Context, DC,
6619 D.getLocStart(), NameInfo, R,
6620 TInfo, SC, isInline,
6621 HasPrototype, false);
6622 if (D.isInvalidType())
6623 NewFD->setInvalidDecl();
6628 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
6629 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
6631 // Check that the return type is not an abstract class type.
6632 // For record types, this is done by the AbstractClassUsageDiagnoser once
6633 // the class has been completely parsed.
6634 if (!DC->isRecord() &&
6635 SemaRef.RequireNonAbstractType(
6636 D.getIdentifierLoc(), R->getAs<FunctionType>()->getReturnType(),
6637 diag::err_abstract_type_in_decl, SemaRef.AbstractReturnType))
6640 if (Name.getNameKind() == DeclarationName::CXXConstructorName) {
6641 // This is a C++ constructor declaration.
6642 assert(DC->isRecord() &&
6643 "Constructors can only be declared in a member context");
6645 R = SemaRef.CheckConstructorDeclarator(D, R, SC);
6646 return CXXConstructorDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
6647 D.getLocStart(), NameInfo,
6648 R, TInfo, isExplicit, isInline,
6649 /*isImplicitlyDeclared=*/false,
6652 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
6653 // This is a C++ destructor declaration.
6654 if (DC->isRecord()) {
6655 R = SemaRef.CheckDestructorDeclarator(D, R, SC);
6656 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
6657 CXXDestructorDecl *NewDD = CXXDestructorDecl::Create(
6658 SemaRef.Context, Record,
6660 NameInfo, R, TInfo, isInline,
6661 /*isImplicitlyDeclared=*/false);
6663 // If the class is complete, then we now create the implicit exception
6664 // specification. If the class is incomplete or dependent, we can't do
6666 if (SemaRef.getLangOpts().CPlusPlus11 && !Record->isDependentType() &&
6667 Record->getDefinition() && !Record->isBeingDefined() &&
6668 R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) {
6669 SemaRef.AdjustDestructorExceptionSpec(Record, NewDD);
6672 IsVirtualOkay = true;
6676 SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member);
6679 // Create a FunctionDecl to satisfy the function definition parsing
6681 return FunctionDecl::Create(SemaRef.Context, DC,
6683 D.getIdentifierLoc(), Name, R, TInfo,
6685 /*hasPrototype=*/true, isConstexpr);
6688 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
6689 if (!DC->isRecord()) {
6690 SemaRef.Diag(D.getIdentifierLoc(),
6691 diag::err_conv_function_not_member);
6695 SemaRef.CheckConversionDeclarator(D, R, SC);
6696 IsVirtualOkay = true;
6697 return CXXConversionDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC),
6698 D.getLocStart(), NameInfo,
6699 R, TInfo, isInline, isExplicit,
6700 isConstexpr, SourceLocation());
6702 } else if (DC->isRecord()) {
6703 // If the name of the function is the same as the name of the record,
6704 // then this must be an invalid constructor that has a return type.
6705 // (The parser checks for a return type and makes the declarator a
6706 // constructor if it has no return type).
6707 if (Name.getAsIdentifierInfo() &&
6708 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){
6709 SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type)
6710 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
6711 << SourceRange(D.getIdentifierLoc());
6715 // This is a C++ method declaration.
6716 CXXMethodDecl *Ret = CXXMethodDecl::Create(SemaRef.Context,
6717 cast<CXXRecordDecl>(DC),
6718 D.getLocStart(), NameInfo, R,
6719 TInfo, SC, isInline,
6720 isConstexpr, SourceLocation());
6721 IsVirtualOkay = !Ret->isStatic();
6725 SemaRef.getLangOpts().CPlusPlus && D.getDeclSpec().isFriendSpecified();
6726 if (!isFriend && SemaRef.CurContext->isRecord())
6729 // Determine whether the function was written with a
6730 // prototype. This true when:
6731 // - we're in C++ (where every function has a prototype),
6732 return FunctionDecl::Create(SemaRef.Context, DC,
6734 NameInfo, R, TInfo, SC, isInline,
6735 true/*HasPrototype*/, isConstexpr);
6739 enum OpenCLParamType {
6743 PrivatePtrKernelParam,
6748 static OpenCLParamType getOpenCLKernelParameterType(QualType PT) {
6749 if (PT->isPointerType()) {
6750 QualType PointeeType = PT->getPointeeType();
6751 if (PointeeType->isPointerType())
6752 return PtrPtrKernelParam;
6753 return PointeeType.getAddressSpace() == 0 ? PrivatePtrKernelParam
6757 // TODO: Forbid the other integer types (size_t, ptrdiff_t...) when they can
6758 // be used as builtin types.
6760 if (PT->isImageType())
6761 return PtrKernelParam;
6763 if (PT->isBooleanType())
6764 return InvalidKernelParam;
6767 return InvalidKernelParam;
6769 if (PT->isHalfType())
6770 return InvalidKernelParam;
6772 if (PT->isRecordType())
6773 return RecordKernelParam;
6775 return ValidKernelParam;
6778 static void checkIsValidOpenCLKernelParameter(
6782 llvm::SmallPtrSetImpl<const Type *> &ValidTypes) {
6783 QualType PT = Param->getType();
6785 // Cache the valid types we encounter to avoid rechecking structs that are
6787 if (ValidTypes.count(PT.getTypePtr()))
6790 switch (getOpenCLKernelParameterType(PT)) {
6791 case PtrPtrKernelParam:
6792 // OpenCL v1.2 s6.9.a:
6793 // A kernel function argument cannot be declared as a
6794 // pointer to a pointer type.
6795 S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param);
6799 case PrivatePtrKernelParam:
6800 // OpenCL v1.2 s6.9.a:
6801 // A kernel function argument cannot be declared as a
6802 // pointer to the private address space.
6803 S.Diag(Param->getLocation(), diag::err_opencl_private_ptr_kernel_param);
6807 // OpenCL v1.2 s6.9.k:
6808 // Arguments to kernel functions in a program cannot be declared with the
6809 // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and
6810 // uintptr_t or a struct and/or union that contain fields declared to be
6811 // one of these built-in scalar types.
6813 case InvalidKernelParam:
6814 // OpenCL v1.2 s6.8 n:
6815 // A kernel function argument cannot be declared
6817 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
6821 case PtrKernelParam:
6822 case ValidKernelParam:
6823 ValidTypes.insert(PT.getTypePtr());
6826 case RecordKernelParam:
6830 // Track nested structs we will inspect
6831 SmallVector<const Decl *, 4> VisitStack;
6833 // Track where we are in the nested structs. Items will migrate from
6834 // VisitStack to HistoryStack as we do the DFS for bad field.
6835 SmallVector<const FieldDecl *, 4> HistoryStack;
6836 HistoryStack.push_back(nullptr);
6838 const RecordDecl *PD = PT->castAs<RecordType>()->getDecl();
6839 VisitStack.push_back(PD);
6841 assert(VisitStack.back() && "First decl null?");
6844 const Decl *Next = VisitStack.pop_back_val();
6846 assert(!HistoryStack.empty());
6847 // Found a marker, we have gone up a level
6848 if (const FieldDecl *Hist = HistoryStack.pop_back_val())
6849 ValidTypes.insert(Hist->getType().getTypePtr());
6854 // Adds everything except the original parameter declaration (which is not a
6855 // field itself) to the history stack.
6856 const RecordDecl *RD;
6857 if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) {
6858 HistoryStack.push_back(Field);
6859 RD = Field->getType()->castAs<RecordType>()->getDecl();
6861 RD = cast<RecordDecl>(Next);
6864 // Add a null marker so we know when we've gone back up a level
6865 VisitStack.push_back(nullptr);
6867 for (const auto *FD : RD->fields()) {
6868 QualType QT = FD->getType();
6870 if (ValidTypes.count(QT.getTypePtr()))
6873 OpenCLParamType ParamType = getOpenCLKernelParameterType(QT);
6874 if (ParamType == ValidKernelParam)
6877 if (ParamType == RecordKernelParam) {
6878 VisitStack.push_back(FD);
6882 // OpenCL v1.2 s6.9.p:
6883 // Arguments to kernel functions that are declared to be a struct or union
6884 // do not allow OpenCL objects to be passed as elements of the struct or
6886 if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam ||
6887 ParamType == PrivatePtrKernelParam) {
6888 S.Diag(Param->getLocation(),
6889 diag::err_record_with_pointers_kernel_param)
6890 << PT->isUnionType()
6893 S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT;
6896 S.Diag(PD->getLocation(), diag::note_within_field_of_type)
6897 << PD->getDeclName();
6899 // We have an error, now let's go back up through history and show where
6900 // the offending field came from
6901 for (ArrayRef<const FieldDecl *>::const_iterator I = HistoryStack.begin() + 1,
6902 E = HistoryStack.end(); I != E; ++I) {
6903 const FieldDecl *OuterField = *I;
6904 S.Diag(OuterField->getLocation(), diag::note_within_field_of_type)
6905 << OuterField->getType();
6908 S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here)
6909 << QT->isPointerType()
6914 } while (!VisitStack.empty());
6918 Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
6919 TypeSourceInfo *TInfo, LookupResult &Previous,
6920 MultiTemplateParamsArg TemplateParamLists,
6922 QualType R = TInfo->getType();
6924 assert(R.getTypePtr()->isFunctionType());
6926 // TODO: consider using NameInfo for diagnostic.
6927 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
6928 DeclarationName Name = NameInfo.getName();
6929 StorageClass SC = getFunctionStorageClass(*this, D);
6931 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
6932 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
6933 diag::err_invalid_thread)
6934 << DeclSpec::getSpecifierName(TSCS);
6936 if (D.isFirstDeclarationOfMember())
6937 adjustMemberFunctionCC(R, D.isStaticMember());
6939 bool isFriend = false;
6940 FunctionTemplateDecl *FunctionTemplate = nullptr;
6941 bool isExplicitSpecialization = false;
6942 bool isFunctionTemplateSpecialization = false;
6944 bool isDependentClassScopeExplicitSpecialization = false;
6945 bool HasExplicitTemplateArgs = false;
6946 TemplateArgumentListInfo TemplateArgs;
6948 bool isVirtualOkay = false;
6950 DeclContext *OriginalDC = DC;
6951 bool IsLocalExternDecl = adjustContextForLocalExternDecl(DC);
6953 FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC,
6955 if (!NewFD) return nullptr;
6957 if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer())
6958 NewFD->setTopLevelDeclInObjCContainer();
6960 // Set the lexical context. If this is a function-scope declaration, or has a
6961 // C++ scope specifier, or is the object of a friend declaration, the lexical
6962 // context will be different from the semantic context.
6963 NewFD->setLexicalDeclContext(CurContext);
6965 if (IsLocalExternDecl)
6966 NewFD->setLocalExternDecl();
6968 if (getLangOpts().CPlusPlus) {
6969 bool isInline = D.getDeclSpec().isInlineSpecified();
6970 bool isVirtual = D.getDeclSpec().isVirtualSpecified();
6971 bool isExplicit = D.getDeclSpec().isExplicitSpecified();
6972 bool isConstexpr = D.getDeclSpec().isConstexprSpecified();
6973 isFriend = D.getDeclSpec().isFriendSpecified();
6974 if (isFriend && !isInline && D.isFunctionDefinition()) {
6975 // C++ [class.friend]p5
6976 // A function can be defined in a friend declaration of a
6977 // class . . . . Such a function is implicitly inline.
6978 NewFD->setImplicitlyInline();
6981 // If this is a method defined in an __interface, and is not a constructor
6982 // or an overloaded operator, then set the pure flag (isVirtual will already
6984 if (const CXXRecordDecl *Parent =
6985 dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) {
6986 if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided())
6987 NewFD->setPure(true);
6990 SetNestedNameSpecifier(NewFD, D);
6991 isExplicitSpecialization = false;
6992 isFunctionTemplateSpecialization = false;
6993 if (D.isInvalidType())
6994 NewFD->setInvalidDecl();
6996 // Match up the template parameter lists with the scope specifier, then
6997 // determine whether we have a template or a template specialization.
6998 bool Invalid = false;
6999 if (TemplateParameterList *TemplateParams =
7000 MatchTemplateParametersToScopeSpecifier(
7001 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
7002 D.getCXXScopeSpec(),
7003 D.getName().getKind() == UnqualifiedId::IK_TemplateId
7004 ? D.getName().TemplateId
7006 TemplateParamLists, isFriend, isExplicitSpecialization,
7008 if (TemplateParams->size() > 0) {
7009 // This is a function template
7011 // Check that we can declare a template here.
7012 if (CheckTemplateDeclScope(S, TemplateParams))
7015 // A destructor cannot be a template.
7016 if (Name.getNameKind() == DeclarationName::CXXDestructorName) {
7017 Diag(NewFD->getLocation(), diag::err_destructor_template);
7021 // If we're adding a template to a dependent context, we may need to
7022 // rebuilding some of the types used within the template parameter list,
7023 // now that we know what the current instantiation is.
7024 if (DC->isDependentContext()) {
7025 ContextRAII SavedContext(*this, DC);
7026 if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams))
7031 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC,
7032 NewFD->getLocation(),
7033 Name, TemplateParams,
7035 FunctionTemplate->setLexicalDeclContext(CurContext);
7036 NewFD->setDescribedFunctionTemplate(FunctionTemplate);
7038 // For source fidelity, store the other template param lists.
7039 if (TemplateParamLists.size() > 1) {
7040 NewFD->setTemplateParameterListsInfo(Context,
7041 TemplateParamLists.size() - 1,
7042 TemplateParamLists.data());
7045 // This is a function template specialization.
7046 isFunctionTemplateSpecialization = true;
7047 // For source fidelity, store all the template param lists.
7048 if (TemplateParamLists.size() > 0)
7049 NewFD->setTemplateParameterListsInfo(Context,
7050 TemplateParamLists.size(),
7051 TemplateParamLists.data());
7053 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);".
7055 // We want to remove the "template<>", found here.
7056 SourceRange RemoveRange = TemplateParams->getSourceRange();
7058 // If we remove the template<> and the name is not a
7059 // template-id, we're actually silently creating a problem:
7060 // the friend declaration will refer to an untemplated decl,
7061 // and clearly the user wants a template specialization. So
7062 // we need to insert '<>' after the name.
7063 SourceLocation InsertLoc;
7064 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
7065 InsertLoc = D.getName().getSourceRange().getEnd();
7066 InsertLoc = getLocForEndOfToken(InsertLoc);
7069 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend)
7070 << Name << RemoveRange
7071 << FixItHint::CreateRemoval(RemoveRange)
7072 << FixItHint::CreateInsertion(InsertLoc, "<>");
7077 // All template param lists were matched against the scope specifier:
7078 // this is NOT (an explicit specialization of) a template.
7079 if (TemplateParamLists.size() > 0)
7080 // For source fidelity, store all the template param lists.
7081 NewFD->setTemplateParameterListsInfo(Context,
7082 TemplateParamLists.size(),
7083 TemplateParamLists.data());
7087 NewFD->setInvalidDecl();
7088 if (FunctionTemplate)
7089 FunctionTemplate->setInvalidDecl();
7092 // C++ [dcl.fct.spec]p5:
7093 // The virtual specifier shall only be used in declarations of
7094 // nonstatic class member functions that appear within a
7095 // member-specification of a class declaration; see 10.3.
7097 if (isVirtual && !NewFD->isInvalidDecl()) {
7098 if (!isVirtualOkay) {
7099 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7100 diag::err_virtual_non_function);
7101 } else if (!CurContext->isRecord()) {
7102 // 'virtual' was specified outside of the class.
7103 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7104 diag::err_virtual_out_of_class)
7105 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
7106 } else if (NewFD->getDescribedFunctionTemplate()) {
7107 // C++ [temp.mem]p3:
7108 // A member function template shall not be virtual.
7109 Diag(D.getDeclSpec().getVirtualSpecLoc(),
7110 diag::err_virtual_member_function_template)
7111 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc());
7113 // Okay: Add virtual to the method.
7114 NewFD->setVirtualAsWritten(true);
7117 if (getLangOpts().CPlusPlus14 &&
7118 NewFD->getReturnType()->isUndeducedType())
7119 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual);
7122 if (getLangOpts().CPlusPlus14 &&
7123 (NewFD->isDependentContext() ||
7124 (isFriend && CurContext->isDependentContext())) &&
7125 NewFD->getReturnType()->isUndeducedType()) {
7126 // If the function template is referenced directly (for instance, as a
7127 // member of the current instantiation), pretend it has a dependent type.
7128 // This is not really justified by the standard, but is the only sane
7130 // FIXME: For a friend function, we have not marked the function as being
7131 // a friend yet, so 'isDependentContext' on the FD doesn't work.
7132 const FunctionProtoType *FPT =
7133 NewFD->getType()->castAs<FunctionProtoType>();
7135 SubstAutoType(FPT->getReturnType(), Context.DependentTy);
7136 NewFD->setType(Context.getFunctionType(Result, FPT->getParamTypes(),
7137 FPT->getExtProtoInfo()));
7140 // C++ [dcl.fct.spec]p3:
7141 // The inline specifier shall not appear on a block scope function
7143 if (isInline && !NewFD->isInvalidDecl()) {
7144 if (CurContext->isFunctionOrMethod()) {
7145 // 'inline' is not allowed on block scope function declaration.
7146 Diag(D.getDeclSpec().getInlineSpecLoc(),
7147 diag::err_inline_declaration_block_scope) << Name
7148 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc());
7152 // C++ [dcl.fct.spec]p6:
7153 // The explicit specifier shall be used only in the declaration of a
7154 // constructor or conversion function within its class definition;
7155 // see 12.3.1 and 12.3.2.
7156 if (isExplicit && !NewFD->isInvalidDecl()) {
7157 if (!CurContext->isRecord()) {
7158 // 'explicit' was specified outside of the class.
7159 Diag(D.getDeclSpec().getExplicitSpecLoc(),
7160 diag::err_explicit_out_of_class)
7161 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
7162 } else if (!isa<CXXConstructorDecl>(NewFD) &&
7163 !isa<CXXConversionDecl>(NewFD)) {
7164 // 'explicit' was specified on a function that wasn't a constructor
7165 // or conversion function.
7166 Diag(D.getDeclSpec().getExplicitSpecLoc(),
7167 diag::err_explicit_non_ctor_or_conv_function)
7168 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc());
7173 // C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors
7174 // are implicitly inline.
7175 NewFD->setImplicitlyInline();
7177 // C++11 [dcl.constexpr]p3: functions declared constexpr are required to
7178 // be either constructors or to return a literal type. Therefore,
7179 // destructors cannot be declared constexpr.
7180 if (isa<CXXDestructorDecl>(NewFD))
7181 Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor);
7184 // If __module_private__ was specified, mark the function accordingly.
7185 if (D.getDeclSpec().isModulePrivateSpecified()) {
7186 if (isFunctionTemplateSpecialization) {
7187 SourceLocation ModulePrivateLoc
7188 = D.getDeclSpec().getModulePrivateSpecLoc();
7189 Diag(ModulePrivateLoc, diag::err_module_private_specialization)
7191 << FixItHint::CreateRemoval(ModulePrivateLoc);
7193 NewFD->setModulePrivate();
7194 if (FunctionTemplate)
7195 FunctionTemplate->setModulePrivate();
7200 if (FunctionTemplate) {
7201 FunctionTemplate->setObjectOfFriendDecl();
7202 FunctionTemplate->setAccess(AS_public);
7204 NewFD->setObjectOfFriendDecl();
7205 NewFD->setAccess(AS_public);
7208 // If a function is defined as defaulted or deleted, mark it as such now.
7209 // FIXME: Does this ever happen? ActOnStartOfFunctionDef forces the function
7210 // definition kind to FDK_Definition.
7211 switch (D.getFunctionDefinitionKind()) {
7212 case FDK_Declaration:
7213 case FDK_Definition:
7217 NewFD->setDefaulted();
7221 NewFD->setDeletedAsWritten();
7225 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext &&
7226 D.isFunctionDefinition()) {
7227 // C++ [class.mfct]p2:
7228 // A member function may be defined (8.4) in its class definition, in
7229 // which case it is an inline member function (7.1.2)
7230 NewFD->setImplicitlyInline();
7233 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) &&
7234 !CurContext->isRecord()) {
7235 // C++ [class.static]p1:
7236 // A data or function member of a class may be declared static
7237 // in a class definition, in which case it is a static member of
7240 // Complain about the 'static' specifier if it's on an out-of-line
7241 // member function definition.
7242 Diag(D.getDeclSpec().getStorageClassSpecLoc(),
7243 diag::err_static_out_of_line)
7244 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
7247 // C++11 [except.spec]p15:
7248 // A deallocation function with no exception-specification is treated
7249 // as if it were specified with noexcept(true).
7250 const FunctionProtoType *FPT = R->getAs<FunctionProtoType>();
7251 if ((Name.getCXXOverloadedOperator() == OO_Delete ||
7252 Name.getCXXOverloadedOperator() == OO_Array_Delete) &&
7253 getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec())
7254 NewFD->setType(Context.getFunctionType(
7255 FPT->getReturnType(), FPT->getParamTypes(),
7256 FPT->getExtProtoInfo().withExceptionSpec(EST_BasicNoexcept)));
7259 // Filter out previous declarations that don't match the scope.
7260 FilterLookupForScope(Previous, OriginalDC, S, shouldConsiderLinkage(NewFD),
7261 D.getCXXScopeSpec().isNotEmpty() ||
7262 isExplicitSpecialization ||
7263 isFunctionTemplateSpecialization);
7265 // Handle GNU asm-label extension (encoded as an attribute).
7266 if (Expr *E = (Expr*) D.getAsmLabel()) {
7267 // The parser guarantees this is a string.
7268 StringLiteral *SE = cast<StringLiteral>(E);
7269 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context,
7270 SE->getString(), 0));
7271 } else if (!ExtnameUndeclaredIdentifiers.empty()) {
7272 llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I =
7273 ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier());
7274 if (I != ExtnameUndeclaredIdentifiers.end()) {
7275 NewFD->addAttr(I->second);
7276 ExtnameUndeclaredIdentifiers.erase(I);
7280 // Copy the parameter declarations from the declarator D to the function
7281 // declaration NewFD, if they are available. First scavenge them into Params.
7282 SmallVector<ParmVarDecl*, 16> Params;
7283 if (D.isFunctionDeclarator()) {
7284 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
7286 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs
7287 // function that takes no arguments, not a function that takes a
7288 // single void argument.
7289 // We let through "const void" here because Sema::GetTypeForDeclarator
7290 // already checks for that case.
7291 if (FTIHasNonVoidParameters(FTI) && FTI.Params[0].Param) {
7292 for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) {
7293 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
7294 assert(Param->getDeclContext() != NewFD && "Was set before ?");
7295 Param->setDeclContext(NewFD);
7296 Params.push_back(Param);
7298 if (Param->isInvalidDecl())
7299 NewFD->setInvalidDecl();
7303 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) {
7304 // When we're declaring a function with a typedef, typeof, etc as in the
7305 // following example, we'll need to synthesize (unnamed)
7306 // parameters for use in the declaration.
7309 // typedef void fn(int);
7313 // Synthesize a parameter for each argument type.
7314 for (const auto &AI : FT->param_types()) {
7315 ParmVarDecl *Param =
7316 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), AI);
7317 Param->setScopeInfo(0, Params.size());
7318 Params.push_back(Param);
7321 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 &&
7322 "Should not need args for typedef of non-prototype fn");
7325 // Finally, we know we have the right number of parameters, install them.
7326 NewFD->setParams(Params);
7328 // Find all anonymous symbols defined during the declaration of this function
7329 // and add to NewFD. This lets us track decls such 'enum Y' in:
7331 // void f(enum Y {AA} x) {}
7333 // which would otherwise incorrectly end up in the translation unit scope.
7334 NewFD->setDeclsInPrototypeScope(DeclsInPrototypeScope);
7335 DeclsInPrototypeScope.clear();
7337 if (D.getDeclSpec().isNoreturnSpecified())
7339 ::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(),
7342 // Functions returning a variably modified type violate C99 6.7.5.2p2
7343 // because all functions have linkage.
7344 if (!NewFD->isInvalidDecl() &&
7345 NewFD->getReturnType()->isVariablyModifiedType()) {
7346 Diag(NewFD->getLocation(), diag::err_vm_func_decl);
7347 NewFD->setInvalidDecl();
7350 if (D.isFunctionDefinition() && CodeSegStack.CurrentValue &&
7351 !NewFD->hasAttr<SectionAttr>()) {
7353 SectionAttr::CreateImplicit(Context, SectionAttr::Declspec_allocate,
7354 CodeSegStack.CurrentValue->getString(),
7355 CodeSegStack.CurrentPragmaLocation));
7356 if (UnifySection(CodeSegStack.CurrentValue->getString(),
7357 ASTContext::PSF_Implicit | ASTContext::PSF_Execute |
7358 ASTContext::PSF_Read,
7360 NewFD->dropAttr<SectionAttr>();
7363 // Handle attributes.
7364 ProcessDeclAttributes(S, NewFD, D);
7366 QualType RetType = NewFD->getReturnType();
7367 const CXXRecordDecl *Ret = RetType->isRecordType() ?
7368 RetType->getAsCXXRecordDecl() : RetType->getPointeeCXXRecordDecl();
7369 if (!NewFD->isInvalidDecl() && !NewFD->hasAttr<WarnUnusedResultAttr>() &&
7370 Ret && Ret->hasAttr<WarnUnusedResultAttr>()) {
7371 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
7372 // Attach WarnUnusedResult to functions returning types with that attribute.
7373 // Don't apply the attribute to that type's own non-static member functions
7374 // (to avoid warning on things like assignment operators)
7375 if (!MD || MD->getParent() != Ret)
7376 NewFD->addAttr(WarnUnusedResultAttr::CreateImplicit(Context));
7379 if (getLangOpts().OpenCL) {
7380 // OpenCL v1.1 s6.5: Using an address space qualifier in a function return
7381 // type declaration will generate a compilation error.
7382 unsigned AddressSpace = RetType.getAddressSpace();
7383 if (AddressSpace == LangAS::opencl_local ||
7384 AddressSpace == LangAS::opencl_global ||
7385 AddressSpace == LangAS::opencl_constant) {
7386 Diag(NewFD->getLocation(),
7387 diag::err_opencl_return_value_with_address_space);
7388 NewFD->setInvalidDecl();
7392 if (!getLangOpts().CPlusPlus) {
7393 // Perform semantic checking on the function declaration.
7394 bool isExplicitSpecialization=false;
7395 if (!NewFD->isInvalidDecl() && NewFD->isMain())
7396 CheckMain(NewFD, D.getDeclSpec());
7398 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
7399 CheckMSVCRTEntryPoint(NewFD);
7401 if (!NewFD->isInvalidDecl())
7402 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
7403 isExplicitSpecialization));
7404 else if (!Previous.empty())
7405 // Make graceful recovery from an invalid redeclaration.
7406 D.setRedeclaration(true);
7407 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
7408 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
7409 "previous declaration set still overloaded");
7411 // Diagnose no-prototype function declarations with calling conventions that
7412 // don't support variadic calls. Only do this in C and do it after merging
7413 // possibly prototyped redeclarations.
7414 const FunctionType *FT = NewFD->getType()->castAs<FunctionType>();
7415 if (isa<FunctionNoProtoType>(FT) && !D.isFunctionDefinition()) {
7416 CallingConv CC = FT->getExtInfo().getCC();
7417 if (!supportsVariadicCall(CC)) {
7418 // Windows system headers sometimes accidentally use stdcall without
7419 // (void) parameters, so we relax this to a warning.
7421 CC == CC_X86StdCall ? diag::warn_cconv_knr : diag::err_cconv_knr;
7422 Diag(NewFD->getLocation(), DiagID)
7423 << FunctionType::getNameForCallConv(CC);
7427 // C++11 [replacement.functions]p3:
7428 // The program's definitions shall not be specified as inline.
7430 // N.B. We diagnose declarations instead of definitions per LWG issue 2340.
7432 // Suppress the diagnostic if the function is __attribute__((used)), since
7433 // that forces an external definition to be emitted.
7434 if (D.getDeclSpec().isInlineSpecified() &&
7435 NewFD->isReplaceableGlobalAllocationFunction() &&
7436 !NewFD->hasAttr<UsedAttr>())
7437 Diag(D.getDeclSpec().getInlineSpecLoc(),
7438 diag::ext_operator_new_delete_declared_inline)
7439 << NewFD->getDeclName();
7441 // If the declarator is a template-id, translate the parser's template
7442 // argument list into our AST format.
7443 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
7444 TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
7445 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
7446 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
7447 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
7448 TemplateId->NumArgs);
7449 translateTemplateArguments(TemplateArgsPtr,
7452 HasExplicitTemplateArgs = true;
7454 if (NewFD->isInvalidDecl()) {
7455 HasExplicitTemplateArgs = false;
7456 } else if (FunctionTemplate) {
7457 // Function template with explicit template arguments.
7458 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec)
7459 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc);
7461 HasExplicitTemplateArgs = false;
7463 assert((isFunctionTemplateSpecialization ||
7464 D.getDeclSpec().isFriendSpecified()) &&
7465 "should have a 'template<>' for this decl");
7466 // "friend void foo<>(int);" is an implicit specialization decl.
7467 isFunctionTemplateSpecialization = true;
7469 } else if (isFriend && isFunctionTemplateSpecialization) {
7470 // This combination is only possible in a recovery case; the user
7471 // wrote something like:
7472 // template <> friend void foo(int);
7473 // which we're recovering from as if the user had written:
7474 // friend void foo<>(int);
7475 // Go ahead and fake up a template id.
7476 HasExplicitTemplateArgs = true;
7477 TemplateArgs.setLAngleLoc(D.getIdentifierLoc());
7478 TemplateArgs.setRAngleLoc(D.getIdentifierLoc());
7481 // If it's a friend (and only if it's a friend), it's possible
7482 // that either the specialized function type or the specialized
7483 // template is dependent, and therefore matching will fail. In
7484 // this case, don't check the specialization yet.
7485 bool InstantiationDependent = false;
7486 if (isFunctionTemplateSpecialization && isFriend &&
7487 (NewFD->getType()->isDependentType() || DC->isDependentContext() ||
7488 TemplateSpecializationType::anyDependentTemplateArguments(
7489 TemplateArgs.getArgumentArray(), TemplateArgs.size(),
7490 InstantiationDependent))) {
7491 assert(HasExplicitTemplateArgs &&
7492 "friend function specialization without template args");
7493 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs,
7495 NewFD->setInvalidDecl();
7496 } else if (isFunctionTemplateSpecialization) {
7497 if (CurContext->isDependentContext() && CurContext->isRecord()
7499 isDependentClassScopeExplicitSpecialization = true;
7500 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
7501 diag::ext_function_specialization_in_class :
7502 diag::err_function_specialization_in_class)
7503 << NewFD->getDeclName();
7504 } else if (CheckFunctionTemplateSpecialization(NewFD,
7505 (HasExplicitTemplateArgs ? &TemplateArgs
7508 NewFD->setInvalidDecl();
7511 // A storage-class-specifier shall not be specified in an explicit
7512 // specialization (14.7.3)
7513 FunctionTemplateSpecializationInfo *Info =
7514 NewFD->getTemplateSpecializationInfo();
7515 if (Info && SC != SC_None) {
7516 if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass())
7517 Diag(NewFD->getLocation(),
7518 diag::err_explicit_specialization_inconsistent_storage_class)
7520 << FixItHint::CreateRemoval(
7521 D.getDeclSpec().getStorageClassSpecLoc());
7524 Diag(NewFD->getLocation(),
7525 diag::ext_explicit_specialization_storage_class)
7526 << FixItHint::CreateRemoval(
7527 D.getDeclSpec().getStorageClassSpecLoc());
7530 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) {
7531 if (CheckMemberSpecialization(NewFD, Previous))
7532 NewFD->setInvalidDecl();
7535 // Perform semantic checking on the function declaration.
7536 if (!isDependentClassScopeExplicitSpecialization) {
7537 if (!NewFD->isInvalidDecl() && NewFD->isMain())
7538 CheckMain(NewFD, D.getDeclSpec());
7540 if (!NewFD->isInvalidDecl() && NewFD->isMSVCRTEntryPoint())
7541 CheckMSVCRTEntryPoint(NewFD);
7543 if (!NewFD->isInvalidDecl())
7544 D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous,
7545 isExplicitSpecialization));
7548 assert((NewFD->isInvalidDecl() || !D.isRedeclaration() ||
7549 Previous.getResultKind() != LookupResult::FoundOverloaded) &&
7550 "previous declaration set still overloaded");
7552 NamedDecl *PrincipalDecl = (FunctionTemplate
7553 ? cast<NamedDecl>(FunctionTemplate)
7556 if (isFriend && D.isRedeclaration()) {
7557 AccessSpecifier Access = AS_public;
7558 if (!NewFD->isInvalidDecl())
7559 Access = NewFD->getPreviousDecl()->getAccess();
7561 NewFD->setAccess(Access);
7562 if (FunctionTemplate) FunctionTemplate->setAccess(Access);
7565 if (NewFD->isOverloadedOperator() && !DC->isRecord() &&
7566 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary))
7567 PrincipalDecl->setNonMemberOperator();
7569 // If we have a function template, check the template parameter
7570 // list. This will check and merge default template arguments.
7571 if (FunctionTemplate) {
7572 FunctionTemplateDecl *PrevTemplate =
7573 FunctionTemplate->getPreviousDecl();
7574 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(),
7575 PrevTemplate ? PrevTemplate->getTemplateParameters()
7577 D.getDeclSpec().isFriendSpecified()
7578 ? (D.isFunctionDefinition()
7579 ? TPC_FriendFunctionTemplateDefinition
7580 : TPC_FriendFunctionTemplate)
7581 : (D.getCXXScopeSpec().isSet() &&
7582 DC && DC->isRecord() &&
7583 DC->isDependentContext())
7584 ? TPC_ClassTemplateMember
7585 : TPC_FunctionTemplate);
7588 if (NewFD->isInvalidDecl()) {
7589 // Ignore all the rest of this.
7590 } else if (!D.isRedeclaration()) {
7591 struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists,
7593 // Fake up an access specifier if it's supposed to be a class member.
7594 if (isa<CXXRecordDecl>(NewFD->getDeclContext()))
7595 NewFD->setAccess(AS_public);
7597 // Qualified decls generally require a previous declaration.
7598 if (D.getCXXScopeSpec().isSet()) {
7599 // ...with the major exception of templated-scope or
7600 // dependent-scope friend declarations.
7602 // TODO: we currently also suppress this check in dependent
7603 // contexts because (1) the parameter depth will be off when
7604 // matching friend templates and (2) we might actually be
7605 // selecting a friend based on a dependent factor. But there
7606 // are situations where these conditions don't apply and we
7607 // can actually do this check immediately.
7609 (TemplateParamLists.size() ||
7610 D.getCXXScopeSpec().getScopeRep()->isDependent() ||
7611 CurContext->isDependentContext())) {
7614 // The user tried to provide an out-of-line definition for a
7615 // function that is a member of a class or namespace, but there
7616 // was no such member function declared (C++ [class.mfct]p2,
7617 // C++ [namespace.memdef]p2). For example:
7623 // void X::f() { } // ill-formed
7625 // Complain about this problem, and attempt to suggest close
7626 // matches (e.g., those that differ only in cv-qualifiers and
7627 // whether the parameter types are references).
7629 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
7630 *this, Previous, NewFD, ExtraArgs, false, nullptr)) {
7631 AddToScope = ExtraArgs.AddToScope;
7636 // Unqualified local friend declarations are required to resolve
7638 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) {
7639 if (NamedDecl *Result = DiagnoseInvalidRedeclaration(
7640 *this, Previous, NewFD, ExtraArgs, true, S)) {
7641 AddToScope = ExtraArgs.AddToScope;
7646 } else if (!D.isFunctionDefinition() &&
7647 isa<CXXMethodDecl>(NewFD) && NewFD->isOutOfLine() &&
7648 !isFriend && !isFunctionTemplateSpecialization &&
7649 !isExplicitSpecialization) {
7650 // An out-of-line member function declaration must also be a
7651 // definition (C++ [class.mfct]p2).
7652 // Note that this is not the case for explicit specializations of
7653 // function templates or member functions of class templates, per
7654 // C++ [temp.expl.spec]p2. We also allow these declarations as an
7655 // extension for compatibility with old SWIG code which likes to
7657 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration)
7658 << D.getCXXScopeSpec().getRange();
7662 ProcessPragmaWeak(S, NewFD);
7663 checkAttributesAfterMerging(*this, *NewFD);
7665 AddKnownFunctionAttributes(NewFD);
7667 if (NewFD->hasAttr<OverloadableAttr>() &&
7668 !NewFD->getType()->getAs<FunctionProtoType>()) {
7669 Diag(NewFD->getLocation(),
7670 diag::err_attribute_overloadable_no_prototype)
7673 // Turn this into a variadic function with no parameters.
7674 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>();
7675 FunctionProtoType::ExtProtoInfo EPI(
7676 Context.getDefaultCallingConvention(true, false));
7677 EPI.Variadic = true;
7678 EPI.ExtInfo = FT->getExtInfo();
7680 QualType R = Context.getFunctionType(FT->getReturnType(), None, EPI);
7684 // If there's a #pragma GCC visibility in scope, and this isn't a class
7685 // member, set the visibility of this function.
7686 if (!DC->isRecord() && NewFD->isExternallyVisible())
7687 AddPushedVisibilityAttribute(NewFD);
7689 // If there's a #pragma clang arc_cf_code_audited in scope, consider
7690 // marking the function.
7691 AddCFAuditedAttribute(NewFD);
7693 // If this is a function definition, check if we have to apply optnone due to
7695 if(D.isFunctionDefinition())
7696 AddRangeBasedOptnone(NewFD);
7698 // If this is the first declaration of an extern C variable, update
7699 // the map of such variables.
7700 if (NewFD->isFirstDecl() && !NewFD->isInvalidDecl() &&
7701 isIncompleteDeclExternC(*this, NewFD))
7702 RegisterLocallyScopedExternCDecl(NewFD, S);
7704 // Set this FunctionDecl's range up to the right paren.
7705 NewFD->setRangeEnd(D.getSourceRange().getEnd());
7707 if (D.isRedeclaration() && !Previous.empty()) {
7708 checkDLLAttributeRedeclaration(
7709 *this, dyn_cast<NamedDecl>(Previous.getRepresentativeDecl()), NewFD,
7710 isExplicitSpecialization || isFunctionTemplateSpecialization);
7713 if (getLangOpts().CPlusPlus) {
7714 if (FunctionTemplate) {
7715 if (NewFD->isInvalidDecl())
7716 FunctionTemplate->setInvalidDecl();
7717 return FunctionTemplate;
7721 if (NewFD->hasAttr<OpenCLKernelAttr>()) {
7722 // OpenCL v1.2 s6.8 static is invalid for kernel functions.
7723 if ((getLangOpts().OpenCLVersion >= 120)
7724 && (SC == SC_Static)) {
7725 Diag(D.getIdentifierLoc(), diag::err_static_kernel);
7729 // OpenCL v1.2, s6.9 -- Kernels can only have return type void.
7730 if (!NewFD->getReturnType()->isVoidType()) {
7731 SourceRange RTRange = NewFD->getReturnTypeSourceRange();
7732 Diag(D.getIdentifierLoc(), diag::err_expected_kernel_void_return_type)
7733 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "void")
7738 llvm::SmallPtrSet<const Type *, 16> ValidTypes;
7739 for (auto Param : NewFD->params())
7740 checkIsValidOpenCLKernelParameter(*this, D, Param, ValidTypes);
7743 MarkUnusedFileScopedDecl(NewFD);
7745 if (getLangOpts().CUDA)
7746 if (IdentifierInfo *II = NewFD->getIdentifier())
7747 if (!NewFD->isInvalidDecl() &&
7748 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
7749 if (II->isStr("cudaConfigureCall")) {
7750 if (!R->getAs<FunctionType>()->getReturnType()->isScalarType())
7751 Diag(NewFD->getLocation(), diag::err_config_scalar_return);
7753 Context.setcudaConfigureCallDecl(NewFD);
7757 // Here we have an function template explicit specialization at class scope.
7758 // The actually specialization will be postponed to template instatiation
7759 // time via the ClassScopeFunctionSpecializationDecl node.
7760 if (isDependentClassScopeExplicitSpecialization) {
7761 ClassScopeFunctionSpecializationDecl *NewSpec =
7762 ClassScopeFunctionSpecializationDecl::Create(
7763 Context, CurContext, SourceLocation(),
7764 cast<CXXMethodDecl>(NewFD),
7765 HasExplicitTemplateArgs, TemplateArgs);
7766 CurContext->addDecl(NewSpec);
7773 /// \brief Perform semantic checking of a new function declaration.
7775 /// Performs semantic analysis of the new function declaration
7776 /// NewFD. This routine performs all semantic checking that does not
7777 /// require the actual declarator involved in the declaration, and is
7778 /// used both for the declaration of functions as they are parsed
7779 /// (called via ActOnDeclarator) and for the declaration of functions
7780 /// that have been instantiated via C++ template instantiation (called
7781 /// via InstantiateDecl).
7783 /// \param IsExplicitSpecialization whether this new function declaration is
7784 /// an explicit specialization of the previous declaration.
7786 /// This sets NewFD->isInvalidDecl() to true if there was an error.
7788 /// \returns true if the function declaration is a redeclaration.
7789 bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
7790 LookupResult &Previous,
7791 bool IsExplicitSpecialization) {
7792 assert(!NewFD->getReturnType()->isVariablyModifiedType() &&
7793 "Variably modified return types are not handled here");
7795 // Determine whether the type of this function should be merged with
7796 // a previous visible declaration. This never happens for functions in C++,
7797 // and always happens in C if the previous declaration was visible.
7798 bool MergeTypeWithPrevious = !getLangOpts().CPlusPlus &&
7799 !Previous.isShadowed();
7801 // Filter out any non-conflicting previous declarations.
7802 filterNonConflictingPreviousDecls(Context, NewFD, Previous);
7804 bool Redeclaration = false;
7805 NamedDecl *OldDecl = nullptr;
7807 // Merge or overload the declaration with an existing declaration of
7808 // the same name, if appropriate.
7809 if (!Previous.empty()) {
7810 // Determine whether NewFD is an overload of PrevDecl or
7811 // a declaration that requires merging. If it's an overload,
7812 // there's no more work to do here; we'll just add the new
7813 // function to the scope.
7814 if (!AllowOverloadingOfFunction(Previous, Context)) {
7815 NamedDecl *Candidate = Previous.getFoundDecl();
7816 if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) {
7817 Redeclaration = true;
7818 OldDecl = Candidate;
7821 switch (CheckOverload(S, NewFD, Previous, OldDecl,
7822 /*NewIsUsingDecl*/ false)) {
7824 Redeclaration = true;
7827 case Ovl_NonFunction:
7828 Redeclaration = true;
7832 Redeclaration = false;
7836 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
7837 // If a function name is overloadable in C, then every function
7838 // with that name must be marked "overloadable".
7839 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
7840 << Redeclaration << NewFD;
7841 NamedDecl *OverloadedDecl = nullptr;
7843 OverloadedDecl = OldDecl;
7844 else if (!Previous.empty())
7845 OverloadedDecl = Previous.getRepresentativeDecl();
7847 Diag(OverloadedDecl->getLocation(),
7848 diag::note_attribute_overloadable_prev_overload);
7849 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
7854 // Check for a previous extern "C" declaration with this name.
7855 if (!Redeclaration &&
7856 checkForConflictWithNonVisibleExternC(*this, NewFD, Previous)) {
7857 filterNonConflictingPreviousDecls(Context, NewFD, Previous);
7858 if (!Previous.empty()) {
7859 // This is an extern "C" declaration with the same name as a previous
7860 // declaration, and thus redeclares that entity...
7861 Redeclaration = true;
7862 OldDecl = Previous.getFoundDecl();
7863 MergeTypeWithPrevious = false;
7865 // ... except in the presence of __attribute__((overloadable)).
7866 if (OldDecl->hasAttr<OverloadableAttr>()) {
7867 if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) {
7868 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing)
7869 << Redeclaration << NewFD;
7870 Diag(Previous.getFoundDecl()->getLocation(),
7871 diag::note_attribute_overloadable_prev_overload);
7872 NewFD->addAttr(OverloadableAttr::CreateImplicit(Context));
7874 if (IsOverload(NewFD, cast<FunctionDecl>(OldDecl), false)) {
7875 Redeclaration = false;
7882 // C++11 [dcl.constexpr]p8:
7883 // A constexpr specifier for a non-static member function that is not
7884 // a constructor declares that member function to be const.
7886 // This needs to be delayed until we know whether this is an out-of-line
7887 // definition of a static member function.
7889 // This rule is not present in C++1y, so we produce a backwards
7890 // compatibility warning whenever it happens in C++11.
7891 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
7892 if (!getLangOpts().CPlusPlus14 && MD && MD->isConstexpr() &&
7893 !MD->isStatic() && !isa<CXXConstructorDecl>(MD) &&
7894 (MD->getTypeQualifiers() & Qualifiers::Const) == 0) {
7895 CXXMethodDecl *OldMD = nullptr;
7897 OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl->getAsFunction());
7898 if (!OldMD || !OldMD->isStatic()) {
7899 const FunctionProtoType *FPT =
7900 MD->getType()->castAs<FunctionProtoType>();
7901 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
7902 EPI.TypeQuals |= Qualifiers::Const;
7903 MD->setType(Context.getFunctionType(FPT->getReturnType(),
7904 FPT->getParamTypes(), EPI));
7906 // Warn that we did this, if we're not performing template instantiation.
7907 // In that case, we'll have warned already when the template was defined.
7908 if (ActiveTemplateInstantiations.empty()) {
7909 SourceLocation AddConstLoc;
7910 if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
7911 .IgnoreParens().getAs<FunctionTypeLoc>())
7912 AddConstLoc = getLocForEndOfToken(FTL.getRParenLoc());
7914 Diag(MD->getLocation(), diag::warn_cxx14_compat_constexpr_not_const)
7915 << FixItHint::CreateInsertion(AddConstLoc, " const");
7920 if (Redeclaration) {
7921 // NewFD and OldDecl represent declarations that need to be
7923 if (MergeFunctionDecl(NewFD, OldDecl, S, MergeTypeWithPrevious)) {
7924 NewFD->setInvalidDecl();
7925 return Redeclaration;
7929 Previous.addDecl(OldDecl);
7931 if (FunctionTemplateDecl *OldTemplateDecl
7932 = dyn_cast<FunctionTemplateDecl>(OldDecl)) {
7933 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl());
7934 FunctionTemplateDecl *NewTemplateDecl
7935 = NewFD->getDescribedFunctionTemplate();
7936 assert(NewTemplateDecl && "Template/non-template mismatch");
7937 if (CXXMethodDecl *Method
7938 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) {
7939 Method->setAccess(OldTemplateDecl->getAccess());
7940 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess());
7943 // If this is an explicit specialization of a member that is a function
7944 // template, mark it as a member specialization.
7945 if (IsExplicitSpecialization &&
7946 NewTemplateDecl->getInstantiatedFromMemberTemplate()) {
7947 NewTemplateDecl->setMemberSpecialization();
7948 assert(OldTemplateDecl->isMemberSpecialization());
7952 // This needs to happen first so that 'inline' propagates.
7953 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl));
7955 if (isa<CXXMethodDecl>(NewFD)) {
7956 // A valid redeclaration of a C++ method must be out-of-line,
7957 // but (unfortunately) it's not necessarily a definition
7958 // because of templates, which means that the previous
7959 // declaration is not necessarily from the class definition.
7961 // For just setting the access, that doesn't matter.
7962 CXXMethodDecl *oldMethod = cast<CXXMethodDecl>(OldDecl);
7963 NewFD->setAccess(oldMethod->getAccess());
7965 // Update the key-function state if necessary for this ABI.
7966 if (NewFD->isInlined() &&
7967 !Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline()) {
7968 // setNonKeyFunction needs to work with the original
7969 // declaration from the class definition, and isVirtual() is
7970 // just faster in that case, so map back to that now.
7971 oldMethod = cast<CXXMethodDecl>(oldMethod->getFirstDecl());
7972 if (oldMethod->isVirtual()) {
7973 Context.setNonKeyFunction(oldMethod);
7980 // Semantic checking for this function declaration (in isolation).
7982 if (getLangOpts().CPlusPlus) {
7983 // C++-specific checks.
7984 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) {
7985 CheckConstructor(Constructor);
7986 } else if (CXXDestructorDecl *Destructor =
7987 dyn_cast<CXXDestructorDecl>(NewFD)) {
7988 CXXRecordDecl *Record = Destructor->getParent();
7989 QualType ClassType = Context.getTypeDeclType(Record);
7991 // FIXME: Shouldn't we be able to perform this check even when the class
7992 // type is dependent? Both gcc and edg can handle that.
7993 if (!ClassType->isDependentType()) {
7994 DeclarationName Name
7995 = Context.DeclarationNames.getCXXDestructorName(
7996 Context.getCanonicalType(ClassType));
7997 if (NewFD->getDeclName() != Name) {
7998 Diag(NewFD->getLocation(), diag::err_destructor_name);
7999 NewFD->setInvalidDecl();
8000 return Redeclaration;
8003 } else if (CXXConversionDecl *Conversion
8004 = dyn_cast<CXXConversionDecl>(NewFD)) {
8005 ActOnConversionDeclarator(Conversion);
8008 // Find any virtual functions that this function overrides.
8009 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) {
8010 if (!Method->isFunctionTemplateSpecialization() &&
8011 !Method->getDescribedFunctionTemplate() &&
8012 Method->isCanonicalDecl()) {
8013 if (AddOverriddenMethods(Method->getParent(), Method)) {
8014 // If the function was marked as "static", we have a problem.
8015 if (NewFD->getStorageClass() == SC_Static) {
8016 ReportOverrides(*this, diag::err_static_overrides_virtual, Method);
8021 if (Method->isStatic())
8022 checkThisInStaticMemberFunctionType(Method);
8025 // Extra checking for C++ overloaded operators (C++ [over.oper]).
8026 if (NewFD->isOverloadedOperator() &&
8027 CheckOverloadedOperatorDeclaration(NewFD)) {
8028 NewFD->setInvalidDecl();
8029 return Redeclaration;
8032 // Extra checking for C++0x literal operators (C++0x [over.literal]).
8033 if (NewFD->getLiteralIdentifier() &&
8034 CheckLiteralOperatorDeclaration(NewFD)) {
8035 NewFD->setInvalidDecl();
8036 return Redeclaration;
8039 // In C++, check default arguments now that we have merged decls. Unless
8040 // the lexical context is the class, because in this case this is done
8041 // during delayed parsing anyway.
8042 if (!CurContext->isRecord())
8043 CheckCXXDefaultArguments(NewFD);
8045 // If this function declares a builtin function, check the type of this
8046 // declaration against the expected type for the builtin.
8047 if (unsigned BuiltinID = NewFD->getBuiltinID()) {
8048 ASTContext::GetBuiltinTypeError Error;
8049 LookupPredefedObjCSuperType(*this, S, NewFD->getIdentifier());
8050 QualType T = Context.GetBuiltinType(BuiltinID, Error);
8051 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) {
8052 // The type of this function differs from the type of the builtin,
8053 // so forget about the builtin entirely.
8054 Context.BuiltinInfo.ForgetBuiltin(BuiltinID, Context.Idents);
8058 // If this function is declared as being extern "C", then check to see if
8059 // the function returns a UDT (class, struct, or union type) that is not C
8060 // compatible, and if it does, warn the user.
8061 // But, issue any diagnostic on the first declaration only.
8062 if (Previous.empty() && NewFD->isExternC()) {
8063 QualType R = NewFD->getReturnType();
8064 if (R->isIncompleteType() && !R->isVoidType())
8065 Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete)
8067 else if (!R.isPODType(Context) && !R->isVoidType() &&
8068 !R->isObjCObjectPointerType())
8069 Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R;
8072 return Redeclaration;
8075 void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) {
8076 // C++11 [basic.start.main]p3:
8077 // A program that [...] declares main to be inline, static or
8078 // constexpr is ill-formed.
8079 // C11 6.7.4p4: In a hosted environment, no function specifier(s) shall
8080 // appear in a declaration of main.
8081 // static main is not an error under C99, but we should warn about it.
8082 // We accept _Noreturn main as an extension.
8083 if (FD->getStorageClass() == SC_Static)
8084 Diag(DS.getStorageClassSpecLoc(), getLangOpts().CPlusPlus
8085 ? diag::err_static_main : diag::warn_static_main)
8086 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
8087 if (FD->isInlineSpecified())
8088 Diag(DS.getInlineSpecLoc(), diag::err_inline_main)
8089 << FixItHint::CreateRemoval(DS.getInlineSpecLoc());
8090 if (DS.isNoreturnSpecified()) {
8091 SourceLocation NoreturnLoc = DS.getNoreturnSpecLoc();
8092 SourceRange NoreturnRange(NoreturnLoc, getLocForEndOfToken(NoreturnLoc));
8093 Diag(NoreturnLoc, diag::ext_noreturn_main);
8094 Diag(NoreturnLoc, diag::note_main_remove_noreturn)
8095 << FixItHint::CreateRemoval(NoreturnRange);
8097 if (FD->isConstexpr()) {
8098 Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_main)
8099 << FixItHint::CreateRemoval(DS.getConstexprSpecLoc());
8100 FD->setConstexpr(false);
8103 if (getLangOpts().OpenCL) {
8104 Diag(FD->getLocation(), diag::err_opencl_no_main)
8105 << FD->hasAttr<OpenCLKernelAttr>();
8106 FD->setInvalidDecl();
8110 QualType T = FD->getType();
8111 assert(T->isFunctionType() && "function decl is not of function type");
8112 const FunctionType* FT = T->castAs<FunctionType>();
8114 if (getLangOpts().GNUMode && !getLangOpts().CPlusPlus) {
8115 // In C with GNU extensions we allow main() to have non-integer return
8116 // type, but we should warn about the extension, and we disable the
8117 // implicit-return-zero rule.
8119 // GCC in C mode accepts qualified 'int'.
8120 if (Context.hasSameUnqualifiedType(FT->getReturnType(), Context.IntTy))
8121 FD->setHasImplicitReturnZero(true);
8123 Diag(FD->getTypeSpecStartLoc(), diag::ext_main_returns_nonint);
8124 SourceRange RTRange = FD->getReturnTypeSourceRange();
8125 if (RTRange.isValid())
8126 Diag(RTRange.getBegin(), diag::note_main_change_return_type)
8127 << FixItHint::CreateReplacement(RTRange, "int");
8130 // In C and C++, main magically returns 0 if you fall off the end;
8131 // set the flag which tells us that.
8132 // This is C++ [basic.start.main]p5 and C99 5.1.2.2.3.
8134 // All the standards say that main() should return 'int'.
8135 if (Context.hasSameType(FT->getReturnType(), Context.IntTy))
8136 FD->setHasImplicitReturnZero(true);
8138 // Otherwise, this is just a flat-out error.
8139 SourceRange RTRange = FD->getReturnTypeSourceRange();
8140 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint)
8141 << (RTRange.isValid() ? FixItHint::CreateReplacement(RTRange, "int")
8143 FD->setInvalidDecl(true);
8147 // Treat protoless main() as nullary.
8148 if (isa<FunctionNoProtoType>(FT)) return;
8150 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT);
8151 unsigned nparams = FTP->getNumParams();
8152 assert(FD->getNumParams() == nparams);
8154 bool HasExtraParameters = (nparams > 3);
8156 // Darwin passes an undocumented fourth argument of type char**. If
8157 // other platforms start sprouting these, the logic below will start
8159 if (nparams == 4 && Context.getTargetInfo().getTriple().isOSDarwin())
8160 HasExtraParameters = false;
8162 if (HasExtraParameters) {
8163 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams;
8164 FD->setInvalidDecl(true);
8168 // FIXME: a lot of the following diagnostics would be improved
8169 // if we had some location information about types.
8172 Context.getPointerType(Context.getPointerType(Context.CharTy));
8173 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP };
8175 for (unsigned i = 0; i < nparams; ++i) {
8176 QualType AT = FTP->getParamType(i);
8178 bool mismatch = true;
8180 if (Context.hasSameUnqualifiedType(AT, Expected[i]))
8182 else if (Expected[i] == CharPP) {
8183 // As an extension, the following forms are okay:
8185 // char const * const *
8188 QualifierCollector qs;
8189 const PointerType* PT;
8190 if ((PT = qs.strip(AT)->getAs<PointerType>()) &&
8191 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) &&
8192 Context.hasSameType(QualType(qs.strip(PT->getPointeeType()), 0),
8195 mismatch = !qs.empty();
8200 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i];
8201 // TODO: suggest replacing given type with expected type
8202 FD->setInvalidDecl(true);
8206 if (nparams == 1 && !FD->isInvalidDecl()) {
8207 Diag(FD->getLocation(), diag::warn_main_one_arg);
8210 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
8211 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
8212 FD->setInvalidDecl();
8216 void Sema::CheckMSVCRTEntryPoint(FunctionDecl *FD) {
8217 QualType T = FD->getType();
8218 assert(T->isFunctionType() && "function decl is not of function type");
8219 const FunctionType *FT = T->castAs<FunctionType>();
8221 // Set an implicit return of 'zero' if the function can return some integral,
8222 // enumeration, pointer or nullptr type.
8223 if (FT->getReturnType()->isIntegralOrEnumerationType() ||
8224 FT->getReturnType()->isAnyPointerType() ||
8225 FT->getReturnType()->isNullPtrType())
8226 // DllMain is exempt because a return value of zero means it failed.
8227 if (FD->getName() != "DllMain")
8228 FD->setHasImplicitReturnZero(true);
8230 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) {
8231 Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD;
8232 FD->setInvalidDecl();
8236 bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) {
8237 // FIXME: Need strict checking. In C89, we need to check for
8238 // any assignment, increment, decrement, function-calls, or
8239 // commas outside of a sizeof. In C99, it's the same list,
8240 // except that the aforementioned are allowed in unevaluated
8241 // expressions. Everything else falls under the
8242 // "may accept other forms of constant expressions" exception.
8243 // (We never end up here for C++, so the constant expression
8244 // rules there don't matter.)
8245 const Expr *Culprit;
8246 if (Init->isConstantInitializer(Context, false, &Culprit))
8248 Diag(Culprit->getExprLoc(), diag::err_init_element_not_constant)
8249 << Culprit->getSourceRange();
8254 // Visits an initialization expression to see if OrigDecl is evaluated in
8255 // its own initialization and throws a warning if it does.
8256 class SelfReferenceChecker
8257 : public EvaluatedExprVisitor<SelfReferenceChecker> {
8262 bool isReferenceType;
8265 llvm::SmallVector<unsigned, 4> InitFieldIndex;
8267 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited;
8269 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context),
8270 S(S), OrigDecl(OrigDecl) {
8272 isRecordType = false;
8273 isReferenceType = false;
8275 if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) {
8276 isPODType = VD->getType().isPODType(S.Context);
8277 isRecordType = VD->getType()->isRecordType();
8278 isReferenceType = VD->getType()->isReferenceType();
8282 // For most expressions, just call the visitor. For initializer lists,
8283 // track the index of the field being initialized since fields are
8284 // initialized in order allowing use of previously initialized fields.
8285 void CheckExpr(Expr *E) {
8286 InitListExpr *InitList = dyn_cast<InitListExpr>(E);
8292 // Track and increment the index here.
8294 InitFieldIndex.push_back(0);
8295 for (auto Child : InitList->children()) {
8296 CheckExpr(cast<Expr>(Child));
8297 ++InitFieldIndex.back();
8299 InitFieldIndex.pop_back();
8302 // Returns true if MemberExpr is checked and no futher checking is needed.
8303 // Returns false if additional checking is required.
8304 bool CheckInitListMemberExpr(MemberExpr *E, bool CheckReference) {
8305 llvm::SmallVector<FieldDecl*, 4> Fields;
8307 bool ReferenceField = false;
8309 // Get the field memebers used.
8310 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
8311 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
8314 Fields.push_back(FD);
8315 if (FD->getType()->isReferenceType())
8316 ReferenceField = true;
8317 Base = ME->getBase()->IgnoreParenImpCasts();
8320 // Keep checking only if the base Decl is the same.
8321 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base);
8322 if (!DRE || DRE->getDecl() != OrigDecl)
8325 // A reference field can be bound to an unininitialized field.
8326 if (CheckReference && !ReferenceField)
8329 // Convert FieldDecls to their index number.
8330 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
8331 for (auto I = Fields.rbegin(), E = Fields.rend(); I != E; ++I) {
8332 UsedFieldIndex.push_back((*I)->getFieldIndex());
8335 // See if a warning is needed by checking the first difference in index
8336 // numbers. If field being used has index less than the field being
8337 // initialized, then the use is safe.
8338 for (auto UsedIter = UsedFieldIndex.begin(),
8339 UsedEnd = UsedFieldIndex.end(),
8340 OrigIter = InitFieldIndex.begin(),
8341 OrigEnd = InitFieldIndex.end();
8342 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
8343 if (*UsedIter < *OrigIter)
8345 if (*UsedIter > *OrigIter)
8349 // TODO: Add a different warning which will print the field names.
8350 HandleDeclRefExpr(DRE);
8354 // For most expressions, the cast is directly above the DeclRefExpr.
8355 // For conditional operators, the cast can be outside the conditional
8356 // operator if both expressions are DeclRefExpr's.
8357 void HandleValue(Expr *E) {
8358 E = E->IgnoreParens();
8359 if (DeclRefExpr* DRE = dyn_cast<DeclRefExpr>(E)) {
8360 HandleDeclRefExpr(DRE);
8364 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
8365 Visit(CO->getCond());
8366 HandleValue(CO->getTrueExpr());
8367 HandleValue(CO->getFalseExpr());
8371 if (BinaryConditionalOperator *BCO =
8372 dyn_cast<BinaryConditionalOperator>(E)) {
8373 Visit(BCO->getCond());
8374 HandleValue(BCO->getFalseExpr());
8378 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
8379 HandleValue(OVE->getSourceExpr());
8383 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
8384 if (BO->getOpcode() == BO_Comma) {
8385 Visit(BO->getLHS());
8386 HandleValue(BO->getRHS());
8391 if (isa<MemberExpr>(E)) {
8393 if (CheckInitListMemberExpr(cast<MemberExpr>(E),
8394 false /*CheckReference*/))
8398 Expr *Base = E->IgnoreParenImpCasts();
8399 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
8400 // Check for static member variables and don't warn on them.
8401 if (!isa<FieldDecl>(ME->getMemberDecl()))
8403 Base = ME->getBase()->IgnoreParenImpCasts();
8405 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base))
8406 HandleDeclRefExpr(DRE);
8413 // Reference types not handled in HandleValue are handled here since all
8414 // uses of references are bad, not just r-value uses.
8415 void VisitDeclRefExpr(DeclRefExpr *E) {
8416 if (isReferenceType)
8417 HandleDeclRefExpr(E);
8420 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
8421 if (E->getCastKind() == CK_LValueToRValue) {
8422 HandleValue(E->getSubExpr());
8426 Inherited::VisitImplicitCastExpr(E);
8429 void VisitMemberExpr(MemberExpr *E) {
8431 if (CheckInitListMemberExpr(E, true /*CheckReference*/))
8435 // Don't warn on arrays since they can be treated as pointers.
8436 if (E->getType()->canDecayToPointerType()) return;
8438 // Warn when a non-static method call is followed by non-static member
8439 // field accesses, which is followed by a DeclRefExpr.
8440 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl());
8441 bool Warn = (MD && !MD->isStatic());
8442 Expr *Base = E->getBase()->IgnoreParenImpCasts();
8443 while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) {
8444 if (!isa<FieldDecl>(ME->getMemberDecl()))
8446 Base = ME->getBase()->IgnoreParenImpCasts();
8449 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
8451 HandleDeclRefExpr(DRE);
8455 // The base of a MemberExpr is not a MemberExpr or a DeclRefExpr.
8456 // Visit that expression.
8460 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
8461 Expr *Callee = E->getCallee();
8463 if (isa<UnresolvedLookupExpr>(Callee))
8464 return Inherited::VisitCXXOperatorCallExpr(E);
8467 for (auto Arg: E->arguments())
8468 HandleValue(Arg->IgnoreParenImpCasts());
8471 void VisitUnaryOperator(UnaryOperator *E) {
8472 // For POD record types, addresses of its own members are well-defined.
8473 if (E->getOpcode() == UO_AddrOf && isRecordType &&
8474 isa<MemberExpr>(E->getSubExpr()->IgnoreParens())) {
8476 HandleValue(E->getSubExpr());
8480 if (E->isIncrementDecrementOp()) {
8481 HandleValue(E->getSubExpr());
8485 Inherited::VisitUnaryOperator(E);
8488 void VisitObjCMessageExpr(ObjCMessageExpr *E) { return; }
8490 void VisitCXXConstructExpr(CXXConstructExpr *E) {
8491 if (E->getConstructor()->isCopyConstructor()) {
8492 Expr *ArgExpr = E->getArg(0);
8493 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
8494 if (ILE->getNumInits() == 1)
8495 ArgExpr = ILE->getInit(0);
8496 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
8497 if (ICE->getCastKind() == CK_NoOp)
8498 ArgExpr = ICE->getSubExpr();
8499 HandleValue(ArgExpr);
8502 Inherited::VisitCXXConstructExpr(E);
8505 void VisitCallExpr(CallExpr *E) {
8506 // Treat std::move as a use.
8507 if (E->getNumArgs() == 1) {
8508 if (FunctionDecl *FD = E->getDirectCallee()) {
8509 if (FD->isInStdNamespace() && FD->getIdentifier() &&
8510 FD->getIdentifier()->isStr("move")) {
8511 HandleValue(E->getArg(0));
8517 Inherited::VisitCallExpr(E);
8520 void VisitBinaryOperator(BinaryOperator *E) {
8521 if (E->isCompoundAssignmentOp()) {
8522 HandleValue(E->getLHS());
8527 Inherited::VisitBinaryOperator(E);
8530 // A custom visitor for BinaryConditionalOperator is needed because the
8531 // regular visitor would check the condition and true expression separately
8532 // but both point to the same place giving duplicate diagnostics.
8533 void VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
8534 Visit(E->getCond());
8535 Visit(E->getFalseExpr());
8538 void HandleDeclRefExpr(DeclRefExpr *DRE) {
8539 Decl* ReferenceDecl = DRE->getDecl();
8540 if (OrigDecl != ReferenceDecl) return;
8542 if (isReferenceType) {
8543 diag = diag::warn_uninit_self_reference_in_reference_init;
8544 } else if (cast<VarDecl>(OrigDecl)->isStaticLocal()) {
8545 diag = diag::warn_static_self_reference_in_init;
8547 diag = diag::warn_uninit_self_reference_in_init;
8550 S.DiagRuntimeBehavior(DRE->getLocStart(), DRE,
8552 << DRE->getNameInfo().getName()
8553 << OrigDecl->getLocation()
8554 << DRE->getSourceRange());
8558 /// CheckSelfReference - Warns if OrigDecl is used in expression E.
8559 static void CheckSelfReference(Sema &S, Decl* OrigDecl, Expr *E,
8561 // Parameters arguments are occassionially constructed with itself,
8562 // for instance, in recursive functions. Skip them.
8563 if (isa<ParmVarDecl>(OrigDecl))
8566 E = E->IgnoreParens();
8568 // Skip checking T a = a where T is not a record or reference type.
8569 // Doing so is a way to silence uninitialized warnings.
8570 if (!DirectInit && !cast<VarDecl>(OrigDecl)->getType()->isRecordType())
8571 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
8572 if (ICE->getCastKind() == CK_LValueToRValue)
8573 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()))
8574 if (DRE->getDecl() == OrigDecl)
8577 SelfReferenceChecker(S, OrigDecl).CheckExpr(E);
8581 /// AddInitializerToDecl - Adds the initializer Init to the
8582 /// declaration dcl. If DirectInit is true, this is C++ direct
8583 /// initialization rather than copy initialization.
8584 void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init,
8585 bool DirectInit, bool TypeMayContainAuto) {
8586 // If there is no declaration, there was an error parsing it. Just ignore
8588 if (!RealDecl || RealDecl->isInvalidDecl()) {
8589 CorrectDelayedTyposInExpr(Init);
8593 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) {
8594 // With declarators parsed the way they are, the parser cannot
8595 // distinguish between a normal initializer and a pure-specifier.
8596 // Thus this grotesque test.
8598 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 &&
8599 Context.getCanonicalType(IL->getType()) == Context.IntTy)
8600 CheckPureMethod(Method, Init->getSourceRange());
8602 Diag(Method->getLocation(), diag::err_member_function_initialization)
8603 << Method->getDeclName() << Init->getSourceRange();
8604 Method->setInvalidDecl();
8609 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl);
8611 assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here");
8612 Diag(RealDecl->getLocation(), diag::err_illegal_initializer);
8613 RealDecl->setInvalidDecl();
8616 ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
8618 // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for.
8619 if (TypeMayContainAuto && VDecl->getType()->isUndeducedType()) {
8620 Expr *DeduceInit = Init;
8621 // Initializer could be a C++ direct-initializer. Deduction only works if it
8622 // contains exactly one expression.
8623 if (CXXDirectInit) {
8624 if (CXXDirectInit->getNumExprs() == 0) {
8625 // It isn't possible to write this directly, but it is possible to
8626 // end up in this situation with "auto x(some_pack...);"
8627 Diag(CXXDirectInit->getLocStart(),
8628 VDecl->isInitCapture() ? diag::err_init_capture_no_expression
8629 : diag::err_auto_var_init_no_expression)
8630 << VDecl->getDeclName() << VDecl->getType()
8631 << VDecl->getSourceRange();
8632 RealDecl->setInvalidDecl();
8634 } else if (CXXDirectInit->getNumExprs() > 1) {
8635 Diag(CXXDirectInit->getExpr(1)->getLocStart(),
8636 VDecl->isInitCapture()
8637 ? diag::err_init_capture_multiple_expressions
8638 : diag::err_auto_var_init_multiple_expressions)
8639 << VDecl->getDeclName() << VDecl->getType()
8640 << VDecl->getSourceRange();
8641 RealDecl->setInvalidDecl();
8644 DeduceInit = CXXDirectInit->getExpr(0);
8645 if (isa<InitListExpr>(DeduceInit))
8646 Diag(CXXDirectInit->getLocStart(),
8647 diag::err_auto_var_init_paren_braces)
8648 << VDecl->getDeclName() << VDecl->getType()
8649 << VDecl->getSourceRange();
8653 // Expressions default to 'id' when we're in a debugger.
8654 bool DefaultedToAuto = false;
8655 if (getLangOpts().DebuggerCastResultToId &&
8656 Init->getType() == Context.UnknownAnyTy) {
8657 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
8658 if (Result.isInvalid()) {
8659 VDecl->setInvalidDecl();
8662 Init = Result.get();
8663 DefaultedToAuto = true;
8666 QualType DeducedType;
8667 if (DeduceAutoType(VDecl->getTypeSourceInfo(), DeduceInit, DeducedType) ==
8669 DiagnoseAutoDeductionFailure(VDecl, DeduceInit);
8670 if (DeducedType.isNull()) {
8671 RealDecl->setInvalidDecl();
8674 VDecl->setType(DeducedType);
8675 assert(VDecl->isLinkageValid());
8677 // In ARC, infer lifetime.
8678 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(VDecl))
8679 VDecl->setInvalidDecl();
8681 // Warn if we deduced 'id'. 'auto' usually implies type-safety, but using
8682 // 'id' instead of a specific object type prevents most of our usual checks.
8683 // We only want to warn outside of template instantiations, though:
8684 // inside a template, the 'id' could have come from a parameter.
8685 if (ActiveTemplateInstantiations.empty() && !DefaultedToAuto &&
8686 DeducedType->isObjCIdType()) {
8687 SourceLocation Loc =
8688 VDecl->getTypeSourceInfo()->getTypeLoc().getBeginLoc();
8689 Diag(Loc, diag::warn_auto_var_is_id)
8690 << VDecl->getDeclName() << DeduceInit->getSourceRange();
8693 // If this is a redeclaration, check that the type we just deduced matches
8694 // the previously declared type.
8695 if (VarDecl *Old = VDecl->getPreviousDecl()) {
8696 // We never need to merge the type, because we cannot form an incomplete
8697 // array of auto, nor deduce such a type.
8698 MergeVarDeclTypes(VDecl, Old, /*MergeTypeWithPrevious*/false);
8701 // Check the deduced type is valid for a variable declaration.
8702 CheckVariableDeclarationType(VDecl);
8703 if (VDecl->isInvalidDecl())
8706 // If all looks well, warn if this is a case that will change meaning when
8707 // we implement N3922.
8708 if (DirectInit && !CXXDirectInit && isa<InitListExpr>(Init)) {
8709 Diag(Init->getLocStart(),
8710 diag::warn_auto_var_direct_list_init)
8711 << FixItHint::CreateInsertion(Init->getLocStart(), "=");
8715 // dllimport cannot be used on variable definitions.
8716 if (VDecl->hasAttr<DLLImportAttr>() && !VDecl->isStaticDataMember()) {
8717 Diag(VDecl->getLocation(), diag::err_attribute_dllimport_data_definition);
8718 VDecl->setInvalidDecl();
8722 if (VDecl->isLocalVarDecl() && VDecl->hasExternalStorage()) {
8723 // C99 6.7.8p5. C++ has no such restriction, but that is a defect.
8724 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init);
8725 VDecl->setInvalidDecl();
8729 if (!VDecl->getType()->isDependentType()) {
8730 // A definition must end up with a complete type, which means it must be
8731 // complete with the restriction that an array type might be completed by
8732 // the initializer; note that later code assumes this restriction.
8733 QualType BaseDeclType = VDecl->getType();
8734 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType))
8735 BaseDeclType = Array->getElementType();
8736 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType,
8737 diag::err_typecheck_decl_incomplete_type)) {
8738 RealDecl->setInvalidDecl();
8742 // The variable can not have an abstract class type.
8743 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(),
8744 diag::err_abstract_type_in_decl,
8745 AbstractVariableType))
8746 VDecl->setInvalidDecl();
8750 if ((Def = VDecl->getDefinition()) && Def != VDecl) {
8751 Diag(VDecl->getLocation(), diag::err_redefinition)
8752 << VDecl->getDeclName();
8753 Diag(Def->getLocation(), diag::note_previous_definition);
8754 VDecl->setInvalidDecl();
8758 const VarDecl *PrevInit = nullptr;
8759 if (getLangOpts().CPlusPlus) {
8760 // C++ [class.static.data]p4
8761 // If a static data member is of const integral or const
8762 // enumeration type, its declaration in the class definition can
8763 // specify a constant-initializer which shall be an integral
8764 // constant expression (5.19). In that case, the member can appear
8765 // in integral constant expressions. The member shall still be
8766 // defined in a namespace scope if it is used in the program and the
8767 // namespace scope definition shall not contain an initializer.
8769 // We already performed a redefinition check above, but for static
8770 // data members we also need to check whether there was an in-class
8771 // declaration with an initializer.
8772 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) {
8773 Diag(Init->getExprLoc(), diag::err_static_data_member_reinitialization)
8774 << VDecl->getDeclName();
8775 Diag(PrevInit->getInit()->getExprLoc(), diag::note_previous_initializer) << 0;
8779 if (VDecl->hasLocalStorage())
8780 getCurFunction()->setHasBranchProtectedScope();
8782 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) {
8783 VDecl->setInvalidDecl();
8788 // OpenCL 1.1 6.5.2: "Variables allocated in the __local address space inside
8789 // a kernel function cannot be initialized."
8790 if (VDecl->getStorageClass() == SC_OpenCLWorkGroupLocal) {
8791 Diag(VDecl->getLocation(), diag::err_local_cant_init);
8792 VDecl->setInvalidDecl();
8796 // Get the decls type and save a reference for later, since
8797 // CheckInitializerTypes may change it.
8798 QualType DclT = VDecl->getType(), SavT = DclT;
8800 // Expressions default to 'id' when we're in a debugger
8801 // and we are assigning it to a variable of Objective-C pointer type.
8802 if (getLangOpts().DebuggerCastResultToId && DclT->isObjCObjectPointerType() &&
8803 Init->getType() == Context.UnknownAnyTy) {
8804 ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType());
8805 if (Result.isInvalid()) {
8806 VDecl->setInvalidDecl();
8809 Init = Result.get();
8812 // Perform the initialization.
8813 if (!VDecl->isInvalidDecl()) {
8814 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl);
8815 InitializationKind Kind
8817 CXXDirectInit ? InitializationKind::CreateDirect(VDecl->getLocation(),
8818 Init->getLocStart(),
8820 : InitializationKind::CreateDirectList(
8821 VDecl->getLocation())
8822 : InitializationKind::CreateCopy(VDecl->getLocation(),
8823 Init->getLocStart());
8825 MultiExprArg Args = Init;
8827 Args = MultiExprArg(CXXDirectInit->getExprs(),
8828 CXXDirectInit->getNumExprs());
8830 // Try to correct any TypoExprs in the initialization arguments.
8831 for (size_t Idx = 0; Idx < Args.size(); ++Idx) {
8833 CorrectDelayedTyposInExpr(Args[Idx], [this, Entity, Kind](Expr *E) {
8834 InitializationSequence Init(*this, Entity, Kind, MultiExprArg(E));
8835 return Init.Failed() ? ExprError() : E;
8837 if (Res.isInvalid()) {
8838 VDecl->setInvalidDecl();
8839 } else if (Res.get() != Args[Idx]) {
8840 Args[Idx] = Res.get();
8843 if (VDecl->isInvalidDecl())
8846 InitializationSequence InitSeq(*this, Entity, Kind, Args);
8847 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
8848 if (Result.isInvalid()) {
8849 VDecl->setInvalidDecl();
8853 Init = Result.getAs<Expr>();
8856 // Check for self-references within variable initializers.
8857 // Variables declared within a function/method body (except for references)
8858 // are handled by a dataflow analysis.
8859 if (!VDecl->hasLocalStorage() || VDecl->getType()->isRecordType() ||
8860 VDecl->getType()->isReferenceType()) {
8861 CheckSelfReference(*this, RealDecl, Init, DirectInit);
8864 // If the type changed, it means we had an incomplete type that was
8865 // completed by the initializer. For example:
8866 // int ary[] = { 1, 3, 5 };
8867 // "ary" transitions from an IncompleteArrayType to a ConstantArrayType.
8868 if (!VDecl->isInvalidDecl() && (DclT != SavT))
8869 VDecl->setType(DclT);
8871 if (!VDecl->isInvalidDecl()) {
8872 checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init);
8874 if (VDecl->hasAttr<BlocksAttr>())
8875 checkRetainCycles(VDecl, Init);
8877 // It is safe to assign a weak reference into a strong variable.
8878 // Although this code can still have problems:
8879 // id x = self.weakProp;
8880 // id y = self.weakProp;
8881 // we do not warn to warn spuriously when 'x' and 'y' are on separate
8882 // paths through the function. This should be revisited if
8883 // -Wrepeated-use-of-weak is made flow-sensitive.
8884 if (VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong &&
8885 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
8886 Init->getLocStart()))
8887 getCurFunction()->markSafeWeakUse(Init);
8890 // The initialization is usually a full-expression.
8892 // FIXME: If this is a braced initialization of an aggregate, it is not
8893 // an expression, and each individual field initializer is a separate
8894 // full-expression. For instance, in:
8896 // struct Temp { ~Temp(); };
8897 // struct S { S(Temp); };
8898 // struct T { S a, b; } t = { Temp(), Temp() }
8900 // we should destroy the first Temp before constructing the second.
8901 ExprResult Result = ActOnFinishFullExpr(Init, VDecl->getLocation(),
8903 VDecl->isConstexpr());
8904 if (Result.isInvalid()) {
8905 VDecl->setInvalidDecl();
8908 Init = Result.get();
8910 // Attach the initializer to the decl.
8911 VDecl->setInit(Init);
8913 if (VDecl->isLocalVarDecl()) {
8914 // C99 6.7.8p4: All the expressions in an initializer for an object that has
8915 // static storage duration shall be constant expressions or string literals.
8916 // C++ does not have this restriction.
8917 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl()) {
8918 const Expr *Culprit;
8919 if (VDecl->getStorageClass() == SC_Static)
8920 CheckForConstantInitializer(Init, DclT);
8921 // C89 is stricter than C99 for non-static aggregate types.
8922 // C89 6.5.7p3: All the expressions [...] in an initializer list
8923 // for an object that has aggregate or union type shall be
8924 // constant expressions.
8925 else if (!getLangOpts().C99 && VDecl->getType()->isAggregateType() &&
8926 isa<InitListExpr>(Init) &&
8927 !Init->isConstantInitializer(Context, false, &Culprit))
8928 Diag(Culprit->getExprLoc(),
8929 diag::ext_aggregate_init_not_constant)
8930 << Culprit->getSourceRange();
8932 } else if (VDecl->isStaticDataMember() &&
8933 VDecl->getLexicalDeclContext()->isRecord()) {
8934 // This is an in-class initialization for a static data member, e.g.,
8937 // static const int value = 17;
8940 // C++ [class.mem]p4:
8941 // A member-declarator can contain a constant-initializer only
8942 // if it declares a static member (9.4) of const integral or
8943 // const enumeration type, see 9.4.2.
8945 // C++11 [class.static.data]p3:
8946 // If a non-volatile const static data member is of integral or
8947 // enumeration type, its declaration in the class definition can
8948 // specify a brace-or-equal-initializer in which every initalizer-clause
8949 // that is an assignment-expression is a constant expression. A static
8950 // data member of literal type can be declared in the class definition
8951 // with the constexpr specifier; if so, its declaration shall specify a
8952 // brace-or-equal-initializer in which every initializer-clause that is
8953 // an assignment-expression is a constant expression.
8955 // Do nothing on dependent types.
8956 if (DclT->isDependentType()) {
8958 // Allow any 'static constexpr' members, whether or not they are of literal
8959 // type. We separately check that every constexpr variable is of literal
8961 } else if (VDecl->isConstexpr()) {
8963 // Require constness.
8964 } else if (!DclT.isConstQualified()) {
8965 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const)
8966 << Init->getSourceRange();
8967 VDecl->setInvalidDecl();
8969 // We allow integer constant expressions in all cases.
8970 } else if (DclT->isIntegralOrEnumerationType()) {
8971 // Check whether the expression is a constant expression.
8973 if (getLangOpts().CPlusPlus11 && DclT.isVolatileQualified())
8974 // In C++11, a non-constexpr const static data member with an
8975 // in-class initializer cannot be volatile.
8976 Diag(VDecl->getLocation(), diag::err_in_class_initializer_volatile);
8977 else if (Init->isValueDependent())
8978 ; // Nothing to check.
8979 else if (Init->isIntegerConstantExpr(Context, &Loc))
8980 ; // Ok, it's an ICE!
8981 else if (Init->isEvaluatable(Context)) {
8982 // If we can constant fold the initializer through heroics, accept it,
8983 // but report this as a use of an extension for -pedantic.
8984 Diag(Loc, diag::ext_in_class_initializer_non_constant)
8985 << Init->getSourceRange();
8987 // Otherwise, this is some crazy unknown case. Report the issue at the
8988 // location provided by the isIntegerConstantExpr failed check.
8989 Diag(Loc, diag::err_in_class_initializer_non_constant)
8990 << Init->getSourceRange();
8991 VDecl->setInvalidDecl();
8994 // We allow foldable floating-point constants as an extension.
8995 } else if (DclT->isFloatingType()) { // also permits complex, which is ok
8996 // In C++98, this is a GNU extension. In C++11, it is not, but we support
8997 // it anyway and provide a fixit to add the 'constexpr'.
8998 if (getLangOpts().CPlusPlus11) {
8999 Diag(VDecl->getLocation(),
9000 diag::ext_in_class_initializer_float_type_cxx11)
9001 << DclT << Init->getSourceRange();
9002 Diag(VDecl->getLocStart(),
9003 diag::note_in_class_initializer_float_type_cxx11)
9004 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
9006 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type)
9007 << DclT << Init->getSourceRange();
9009 if (!Init->isValueDependent() && !Init->isEvaluatable(Context)) {
9010 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant)
9011 << Init->getSourceRange();
9012 VDecl->setInvalidDecl();
9016 // Suggest adding 'constexpr' in C++11 for literal types.
9017 } else if (getLangOpts().CPlusPlus11 && DclT->isLiteralType(Context)) {
9018 Diag(VDecl->getLocation(), diag::err_in_class_initializer_literal_type)
9019 << DclT << Init->getSourceRange()
9020 << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr ");
9021 VDecl->setConstexpr(true);
9024 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type)
9025 << DclT << Init->getSourceRange();
9026 VDecl->setInvalidDecl();
9028 } else if (VDecl->isFileVarDecl()) {
9029 if (VDecl->getStorageClass() == SC_Extern &&
9030 (!getLangOpts().CPlusPlus ||
9031 !(Context.getBaseElementType(VDecl->getType()).isConstQualified() ||
9032 VDecl->isExternC())) &&
9033 !isTemplateInstantiation(VDecl->getTemplateSpecializationKind()))
9034 Diag(VDecl->getLocation(), diag::warn_extern_init);
9036 // C99 6.7.8p4. All file scoped initializers need to be constant.
9037 if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl())
9038 CheckForConstantInitializer(Init, DclT);
9041 // We will represent direct-initialization similarly to copy-initialization:
9042 // int x(1); -as-> int x = 1;
9043 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c);
9045 // Clients that want to distinguish between the two forms, can check for
9046 // direct initializer using VarDecl::getInitStyle().
9047 // A major benefit is that clients that don't particularly care about which
9048 // exactly form was it (like the CodeGen) can handle both cases without
9049 // special case code.
9052 // The form of initialization (using parentheses or '=') is generally
9053 // insignificant, but does matter when the entity being initialized has a
9055 if (CXXDirectInit) {
9056 assert(DirectInit && "Call-style initializer must be direct init.");
9057 VDecl->setInitStyle(VarDecl::CallInit);
9058 } else if (DirectInit) {
9059 // This must be list-initialization. No other way is direct-initialization.
9060 VDecl->setInitStyle(VarDecl::ListInit);
9063 CheckCompleteVariableDeclaration(VDecl);
9066 /// ActOnInitializerError - Given that there was an error parsing an
9067 /// initializer for the given declaration, try to return to some form
9069 void Sema::ActOnInitializerError(Decl *D) {
9070 // Our main concern here is re-establishing invariants like "a
9071 // variable's type is either dependent or complete".
9072 if (!D || D->isInvalidDecl()) return;
9074 VarDecl *VD = dyn_cast<VarDecl>(D);
9077 // Auto types are meaningless if we can't make sense of the initializer.
9078 if (ParsingInitForAutoVars.count(D)) {
9079 D->setInvalidDecl();
9083 QualType Ty = VD->getType();
9084 if (Ty->isDependentType()) return;
9086 // Require a complete type.
9087 if (RequireCompleteType(VD->getLocation(),
9088 Context.getBaseElementType(Ty),
9089 diag::err_typecheck_decl_incomplete_type)) {
9090 VD->setInvalidDecl();
9094 // Require a non-abstract type.
9095 if (RequireNonAbstractType(VD->getLocation(), Ty,
9096 diag::err_abstract_type_in_decl,
9097 AbstractVariableType)) {
9098 VD->setInvalidDecl();
9102 // Don't bother complaining about constructors or destructors,
9106 void Sema::ActOnUninitializedDecl(Decl *RealDecl,
9107 bool TypeMayContainAuto) {
9108 // If there is no declaration, there was an error parsing it. Just ignore it.
9112 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) {
9113 QualType Type = Var->getType();
9115 // C++11 [dcl.spec.auto]p3
9116 if (TypeMayContainAuto && Type->getContainedAutoType()) {
9117 Diag(Var->getLocation(), diag::err_auto_var_requires_init)
9118 << Var->getDeclName() << Type;
9119 Var->setInvalidDecl();
9123 // C++11 [class.static.data]p3: A static data member can be declared with
9124 // the constexpr specifier; if so, its declaration shall specify
9125 // a brace-or-equal-initializer.
9126 // C++11 [dcl.constexpr]p1: The constexpr specifier shall be applied only to
9127 // the definition of a variable [...] or the declaration of a static data
9129 if (Var->isConstexpr() && !Var->isThisDeclarationADefinition()) {
9130 if (Var->isStaticDataMember())
9131 Diag(Var->getLocation(),
9132 diag::err_constexpr_static_mem_var_requires_init)
9133 << Var->getDeclName();
9135 Diag(Var->getLocation(), diag::err_invalid_constexpr_var_decl);
9136 Var->setInvalidDecl();
9140 // OpenCL v1.1 s6.5.3: variables declared in the constant address space must
9142 if (!Var->isInvalidDecl() &&
9143 Var->getType().getAddressSpace() == LangAS::opencl_constant &&
9144 Var->getStorageClass() != SC_Extern && !Var->getInit()) {
9145 Diag(Var->getLocation(), diag::err_opencl_constant_no_init);
9146 Var->setInvalidDecl();
9150 switch (Var->isThisDeclarationADefinition()) {
9151 case VarDecl::Definition:
9152 if (!Var->isStaticDataMember() || !Var->getAnyInitializer())
9155 // We have an out-of-line definition of a static data member
9156 // that has an in-class initializer, so we type-check this like
9161 case VarDecl::DeclarationOnly:
9162 // It's only a declaration.
9164 // Block scope. C99 6.7p7: If an identifier for an object is
9165 // declared with no linkage (C99 6.2.2p6), the type for the
9166 // object shall be complete.
9167 if (!Type->isDependentType() && Var->isLocalVarDecl() &&
9168 !Var->hasLinkage() && !Var->isInvalidDecl() &&
9169 RequireCompleteType(Var->getLocation(), Type,
9170 diag::err_typecheck_decl_incomplete_type))
9171 Var->setInvalidDecl();
9173 // Make sure that the type is not abstract.
9174 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
9175 RequireNonAbstractType(Var->getLocation(), Type,
9176 diag::err_abstract_type_in_decl,
9177 AbstractVariableType))
9178 Var->setInvalidDecl();
9179 if (!Type->isDependentType() && !Var->isInvalidDecl() &&
9180 Var->getStorageClass() == SC_PrivateExtern) {
9181 Diag(Var->getLocation(), diag::warn_private_extern);
9182 Diag(Var->getLocation(), diag::note_private_extern);
9187 case VarDecl::TentativeDefinition:
9188 // File scope. C99 6.9.2p2: A declaration of an identifier for an
9189 // object that has file scope without an initializer, and without a
9190 // storage-class specifier or with the storage-class specifier "static",
9191 // constitutes a tentative definition. Note: A tentative definition with
9192 // external linkage is valid (C99 6.2.2p5).
9193 if (!Var->isInvalidDecl()) {
9194 if (const IncompleteArrayType *ArrayT
9195 = Context.getAsIncompleteArrayType(Type)) {
9196 if (RequireCompleteType(Var->getLocation(),
9197 ArrayT->getElementType(),
9198 diag::err_illegal_decl_array_incomplete_type))
9199 Var->setInvalidDecl();
9200 } else if (Var->getStorageClass() == SC_Static) {
9201 // C99 6.9.2p3: If the declaration of an identifier for an object is
9202 // a tentative definition and has internal linkage (C99 6.2.2p3), the
9203 // declared type shall not be an incomplete type.
9204 // NOTE: code such as the following
9206 // struct s { int a; };
9207 // is accepted by gcc. Hence here we issue a warning instead of
9208 // an error and we do not invalidate the static declaration.
9209 // NOTE: to avoid multiple warnings, only check the first declaration.
9210 if (Var->isFirstDecl())
9211 RequireCompleteType(Var->getLocation(), Type,
9212 diag::ext_typecheck_decl_incomplete_type);
9216 // Record the tentative definition; we're done.
9217 if (!Var->isInvalidDecl())
9218 TentativeDefinitions.push_back(Var);
9222 // Provide a specific diagnostic for uninitialized variable
9223 // definitions with incomplete array type.
9224 if (Type->isIncompleteArrayType()) {
9225 Diag(Var->getLocation(),
9226 diag::err_typecheck_incomplete_array_needs_initializer);
9227 Var->setInvalidDecl();
9231 // Provide a specific diagnostic for uninitialized variable
9232 // definitions with reference type.
9233 if (Type->isReferenceType()) {
9234 Diag(Var->getLocation(), diag::err_reference_var_requires_init)
9235 << Var->getDeclName()
9236 << SourceRange(Var->getLocation(), Var->getLocation());
9237 Var->setInvalidDecl();
9241 // Do not attempt to type-check the default initializer for a
9242 // variable with dependent type.
9243 if (Type->isDependentType())
9246 if (Var->isInvalidDecl())
9249 if (!Var->hasAttr<AliasAttr>()) {
9250 if (RequireCompleteType(Var->getLocation(),
9251 Context.getBaseElementType(Type),
9252 diag::err_typecheck_decl_incomplete_type)) {
9253 Var->setInvalidDecl();
9258 // The variable can not have an abstract class type.
9259 if (RequireNonAbstractType(Var->getLocation(), Type,
9260 diag::err_abstract_type_in_decl,
9261 AbstractVariableType)) {
9262 Var->setInvalidDecl();
9266 // Check for jumps past the implicit initializer. C++0x
9267 // clarifies that this applies to a "variable with automatic
9268 // storage duration", not a "local variable".
9269 // C++11 [stmt.dcl]p3
9270 // A program that jumps from a point where a variable with automatic
9271 // storage duration is not in scope to a point where it is in scope is
9272 // ill-formed unless the variable has scalar type, class type with a
9273 // trivial default constructor and a trivial destructor, a cv-qualified
9274 // version of one of these types, or an array of one of the preceding
9275 // types and is declared without an initializer.
9276 if (getLangOpts().CPlusPlus && Var->hasLocalStorage()) {
9277 if (const RecordType *Record
9278 = Context.getBaseElementType(Type)->getAs<RecordType>()) {
9279 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl());
9280 // Mark the function for further checking even if the looser rules of
9281 // C++11 do not require such checks, so that we can diagnose
9282 // incompatibilities with C++98.
9283 if (!CXXRecord->isPOD())
9284 getCurFunction()->setHasBranchProtectedScope();
9288 // C++03 [dcl.init]p9:
9289 // If no initializer is specified for an object, and the
9290 // object is of (possibly cv-qualified) non-POD class type (or
9291 // array thereof), the object shall be default-initialized; if
9292 // the object is of const-qualified type, the underlying class
9293 // type shall have a user-declared default
9294 // constructor. Otherwise, if no initializer is specified for
9295 // a non- static object, the object and its subobjects, if
9296 // any, have an indeterminate initial value); if the object
9297 // or any of its subobjects are of const-qualified type, the
9298 // program is ill-formed.
9299 // C++0x [dcl.init]p11:
9300 // If no initializer is specified for an object, the object is
9301 // default-initialized; [...].
9302 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var);
9303 InitializationKind Kind
9304 = InitializationKind::CreateDefault(Var->getLocation());
9306 InitializationSequence InitSeq(*this, Entity, Kind, None);
9307 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, None);
9308 if (Init.isInvalid())
9309 Var->setInvalidDecl();
9310 else if (Init.get()) {
9311 Var->setInit(MaybeCreateExprWithCleanups(Init.get()));
9312 // This is important for template substitution.
9313 Var->setInitStyle(VarDecl::CallInit);
9316 CheckCompleteVariableDeclaration(Var);
9320 void Sema::ActOnCXXForRangeDecl(Decl *D) {
9321 VarDecl *VD = dyn_cast<VarDecl>(D);
9323 Diag(D->getLocation(), diag::err_for_range_decl_must_be_var);
9324 D->setInvalidDecl();
9328 VD->setCXXForRangeDecl(true);
9330 // for-range-declaration cannot be given a storage class specifier.
9332 switch (VD->getStorageClass()) {
9341 case SC_PrivateExtern:
9350 case SC_OpenCLWorkGroupLocal:
9351 llvm_unreachable("Unexpected storage class");
9353 if (VD->isConstexpr())
9356 Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class)
9357 << VD->getDeclName() << Error;
9358 D->setInvalidDecl();
9363 Sema::ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
9364 IdentifierInfo *Ident,
9365 ParsedAttributes &Attrs,
9366 SourceLocation AttrEnd) {
9367 // C++1y [stmt.iter]p1:
9368 // A range-based for statement of the form
9369 // for ( for-range-identifier : for-range-initializer ) statement
9371 // for ( auto&& for-range-identifier : for-range-initializer ) statement
9372 DeclSpec DS(Attrs.getPool().getFactory());
9374 const char *PrevSpec;
9376 DS.SetTypeSpecType(DeclSpec::TST_auto, IdentLoc, PrevSpec, DiagID,
9377 getPrintingPolicy());
9379 Declarator D(DS, Declarator::ForContext);
9380 D.SetIdentifier(Ident, IdentLoc);
9381 D.takeAttributes(Attrs, AttrEnd);
9383 ParsedAttributes EmptyAttrs(Attrs.getPool().getFactory());
9384 D.AddTypeInfo(DeclaratorChunk::getReference(0, IdentLoc, /*lvalue*/false),
9385 EmptyAttrs, IdentLoc);
9386 Decl *Var = ActOnDeclarator(S, D);
9387 cast<VarDecl>(Var)->setCXXForRangeDecl(true);
9388 FinalizeDeclaration(Var);
9389 return ActOnDeclStmt(FinalizeDeclaratorGroup(S, DS, Var), IdentLoc,
9390 AttrEnd.isValid() ? AttrEnd : IdentLoc);
9393 void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
9394 if (var->isInvalidDecl()) return;
9396 // In ARC, don't allow jumps past the implicit initialization of a
9397 // local retaining variable.
9398 if (getLangOpts().ObjCAutoRefCount &&
9399 var->hasLocalStorage()) {
9400 switch (var->getType().getObjCLifetime()) {
9401 case Qualifiers::OCL_None:
9402 case Qualifiers::OCL_ExplicitNone:
9403 case Qualifiers::OCL_Autoreleasing:
9406 case Qualifiers::OCL_Weak:
9407 case Qualifiers::OCL_Strong:
9408 getCurFunction()->setHasBranchProtectedScope();
9413 // Warn about externally-visible variables being defined without a
9414 // prior declaration. We only want to do this for global
9415 // declarations, but we also specifically need to avoid doing it for
9416 // class members because the linkage of an anonymous class can
9417 // change if it's later given a typedef name.
9418 if (var->isThisDeclarationADefinition() &&
9419 var->getDeclContext()->getRedeclContext()->isFileContext() &&
9420 var->isExternallyVisible() && var->hasLinkage() &&
9421 !getDiagnostics().isIgnored(diag::warn_missing_variable_declarations,
9422 var->getLocation())) {
9423 // Find a previous declaration that's not a definition.
9424 VarDecl *prev = var->getPreviousDecl();
9425 while (prev && prev->isThisDeclarationADefinition())
9426 prev = prev->getPreviousDecl();
9429 Diag(var->getLocation(), diag::warn_missing_variable_declarations) << var;
9432 if (var->getTLSKind() == VarDecl::TLS_Static) {
9433 const Expr *Culprit;
9434 if (var->getType().isDestructedType()) {
9435 // GNU C++98 edits for __thread, [basic.start.term]p3:
9436 // The type of an object with thread storage duration shall not
9437 // have a non-trivial destructor.
9438 Diag(var->getLocation(), diag::err_thread_nontrivial_dtor);
9439 if (getLangOpts().CPlusPlus11)
9440 Diag(var->getLocation(), diag::note_use_thread_local);
9441 } else if (getLangOpts().CPlusPlus && var->hasInit() &&
9442 !var->getInit()->isConstantInitializer(
9443 Context, var->getType()->isReferenceType(), &Culprit)) {
9444 // GNU C++98 edits for __thread, [basic.start.init]p4:
9445 // An object of thread storage duration shall not require dynamic
9447 // FIXME: Need strict checking here.
9448 Diag(Culprit->getExprLoc(), diag::err_thread_dynamic_init)
9449 << Culprit->getSourceRange();
9450 if (getLangOpts().CPlusPlus11)
9451 Diag(var->getLocation(), diag::note_use_thread_local);
9456 if (var->isThisDeclarationADefinition() &&
9457 ActiveTemplateInstantiations.empty()) {
9458 PragmaStack<StringLiteral *> *Stack = nullptr;
9459 int SectionFlags = ASTContext::PSF_Implicit | ASTContext::PSF_Read;
9460 if (var->getType().isConstQualified())
9461 Stack = &ConstSegStack;
9462 else if (!var->getInit()) {
9463 Stack = &BSSSegStack;
9464 SectionFlags |= ASTContext::PSF_Write;
9466 Stack = &DataSegStack;
9467 SectionFlags |= ASTContext::PSF_Write;
9469 if (!var->hasAttr<SectionAttr>() && Stack->CurrentValue)
9471 SectionAttr::CreateImplicit(Context, SectionAttr::Declspec_allocate,
9472 Stack->CurrentValue->getString(),
9473 Stack->CurrentPragmaLocation));
9474 if (const SectionAttr *SA = var->getAttr<SectionAttr>())
9475 if (UnifySection(SA->getName(), SectionFlags, var))
9476 var->dropAttr<SectionAttr>();
9478 // Apply the init_seg attribute if this has an initializer. If the
9479 // initializer turns out to not be dynamic, we'll end up ignoring this
9481 if (CurInitSeg && var->getInit())
9482 var->addAttr(InitSegAttr::CreateImplicit(Context, CurInitSeg->getString(),
9486 // All the following checks are C++ only.
9487 if (!getLangOpts().CPlusPlus) return;
9489 QualType type = var->getType();
9490 if (type->isDependentType()) return;
9492 // __block variables might require us to capture a copy-initializer.
9493 if (var->hasAttr<BlocksAttr>()) {
9494 // It's currently invalid to ever have a __block variable with an
9495 // array type; should we diagnose that here?
9497 // Regardless, we don't want to ignore array nesting when
9498 // constructing this copy.
9499 if (type->isStructureOrClassType()) {
9500 EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
9501 SourceLocation poi = var->getLocation();
9502 Expr *varRef =new (Context) DeclRefExpr(var, false, type, VK_LValue, poi);
9504 = PerformMoveOrCopyInitialization(
9505 InitializedEntity::InitializeBlock(poi, type, false),
9506 var, var->getType(), varRef, /*AllowNRVO=*/true);
9507 if (!result.isInvalid()) {
9508 result = MaybeCreateExprWithCleanups(result);
9509 Expr *init = result.getAs<Expr>();
9510 Context.setBlockVarCopyInits(var, init);
9515 Expr *Init = var->getInit();
9516 bool IsGlobal = var->hasGlobalStorage() && !var->isStaticLocal();
9517 QualType baseType = Context.getBaseElementType(type);
9519 if (!var->getDeclContext()->isDependentContext() &&
9520 Init && !Init->isValueDependent()) {
9521 if (IsGlobal && !var->isConstexpr() &&
9522 !getDiagnostics().isIgnored(diag::warn_global_constructor,
9523 var->getLocation())) {
9524 // Warn about globals which don't have a constant initializer. Don't
9525 // warn about globals with a non-trivial destructor because we already
9526 // warned about them.
9527 CXXRecordDecl *RD = baseType->getAsCXXRecordDecl();
9528 if (!(RD && !RD->hasTrivialDestructor()) &&
9529 !Init->isConstantInitializer(Context, baseType->isReferenceType()))
9530 Diag(var->getLocation(), diag::warn_global_constructor)
9531 << Init->getSourceRange();
9534 if (var->isConstexpr()) {
9535 SmallVector<PartialDiagnosticAt, 8> Notes;
9536 if (!var->evaluateValue(Notes) || !var->isInitICE()) {
9537 SourceLocation DiagLoc = var->getLocation();
9538 // If the note doesn't add any useful information other than a source
9539 // location, fold it into the primary diagnostic.
9540 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
9541 diag::note_invalid_subexpr_in_const_expr) {
9542 DiagLoc = Notes[0].first;
9545 Diag(DiagLoc, diag::err_constexpr_var_requires_const_init)
9546 << var << Init->getSourceRange();
9547 for (unsigned I = 0, N = Notes.size(); I != N; ++I)
9548 Diag(Notes[I].first, Notes[I].second);
9550 } else if (var->isUsableInConstantExpressions(Context)) {
9551 // Check whether the initializer of a const variable of integral or
9552 // enumeration type is an ICE now, since we can't tell whether it was
9553 // initialized by a constant expression if we check later.
9554 var->checkInitIsICE();
9558 // Require the destructor.
9559 if (const RecordType *recordType = baseType->getAs<RecordType>())
9560 FinalizeVarWithDestructor(var, recordType);
9563 /// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform
9564 /// any semantic actions necessary after any initializer has been attached.
9566 Sema::FinalizeDeclaration(Decl *ThisDecl) {
9567 // Note that we are no longer parsing the initializer for this declaration.
9568 ParsingInitForAutoVars.erase(ThisDecl);
9570 VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDecl);
9574 checkAttributesAfterMerging(*this, *VD);
9576 // Static locals inherit dll attributes from their function.
9577 if (VD->isStaticLocal()) {
9578 if (FunctionDecl *FD =
9579 dyn_cast_or_null<FunctionDecl>(VD->getParentFunctionOrMethod())) {
9580 if (Attr *A = getDLLAttr(FD)) {
9581 auto *NewAttr = cast<InheritableAttr>(A->clone(getASTContext()));
9582 NewAttr->setInherited(true);
9583 VD->addAttr(NewAttr);
9588 // Grab the dllimport or dllexport attribute off of the VarDecl.
9589 const InheritableAttr *DLLAttr = getDLLAttr(VD);
9591 // Imported static data members cannot be defined out-of-line.
9592 if (const auto *IA = dyn_cast_or_null<DLLImportAttr>(DLLAttr)) {
9593 if (VD->isStaticDataMember() && VD->isOutOfLine() &&
9594 VD->isThisDeclarationADefinition()) {
9595 // We allow definitions of dllimport class template static data members
9597 CXXRecordDecl *Context =
9598 cast<CXXRecordDecl>(VD->getFirstDecl()->getDeclContext());
9599 bool IsClassTemplateMember =
9600 isa<ClassTemplatePartialSpecializationDecl>(Context) ||
9601 Context->getDescribedClassTemplate();
9603 Diag(VD->getLocation(),
9604 IsClassTemplateMember
9605 ? diag::warn_attribute_dllimport_static_field_definition
9606 : diag::err_attribute_dllimport_static_field_definition);
9607 Diag(IA->getLocation(), diag::note_attribute);
9608 if (!IsClassTemplateMember)
9609 VD->setInvalidDecl();
9613 // dllimport/dllexport variables cannot be thread local, their TLS index
9614 // isn't exported with the variable.
9615 if (DLLAttr && VD->getTLSKind()) {
9616 Diag(VD->getLocation(), diag::err_attribute_dll_thread_local) << VD
9618 VD->setInvalidDecl();
9621 if (UsedAttr *Attr = VD->getAttr<UsedAttr>()) {
9622 if (!Attr->isInherited() && !VD->isThisDeclarationADefinition()) {
9623 Diag(Attr->getLocation(), diag::warn_attribute_ignored) << Attr;
9624 VD->dropAttr<UsedAttr>();
9628 if (!VD->isInvalidDecl() &&
9629 VD->isThisDeclarationADefinition() == VarDecl::TentativeDefinition) {
9630 if (const VarDecl *Def = VD->getDefinition()) {
9631 if (Def->hasAttr<AliasAttr>()) {
9632 Diag(VD->getLocation(), diag::err_tentative_after_alias)
9633 << VD->getDeclName();
9634 Diag(Def->getLocation(), diag::note_previous_definition);
9635 VD->setInvalidDecl();
9640 const DeclContext *DC = VD->getDeclContext();
9641 // If there's a #pragma GCC visibility in scope, and this isn't a class
9642 // member, set the visibility of this variable.
9643 if (DC->getRedeclContext()->isFileContext() && VD->isExternallyVisible())
9644 AddPushedVisibilityAttribute(VD);
9646 // FIXME: Warn on unused templates.
9647 if (VD->isFileVarDecl() && !VD->getDescribedVarTemplate() &&
9648 !isa<VarTemplatePartialSpecializationDecl>(VD))
9649 MarkUnusedFileScopedDecl(VD);
9651 // Now we have parsed the initializer and can update the table of magic
9653 if (!VD->hasAttr<TypeTagForDatatypeAttr>() ||
9654 !VD->getType()->isIntegralOrEnumerationType())
9657 for (const auto *I : ThisDecl->specific_attrs<TypeTagForDatatypeAttr>()) {
9658 const Expr *MagicValueExpr = VD->getInit();
9659 if (!MagicValueExpr) {
9662 llvm::APSInt MagicValueInt;
9663 if (!MagicValueExpr->isIntegerConstantExpr(MagicValueInt, Context)) {
9664 Diag(I->getRange().getBegin(),
9665 diag::err_type_tag_for_datatype_not_ice)
9666 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
9669 if (MagicValueInt.getActiveBits() > 64) {
9670 Diag(I->getRange().getBegin(),
9671 diag::err_type_tag_for_datatype_too_large)
9672 << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange();
9675 uint64_t MagicValue = MagicValueInt.getZExtValue();
9676 RegisterTypeTagForDatatype(I->getArgumentKind(),
9678 I->getMatchingCType(),
9679 I->getLayoutCompatible(),
9680 I->getMustBeNull());
9684 Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
9685 ArrayRef<Decl *> Group) {
9686 SmallVector<Decl*, 8> Decls;
9688 if (DS.isTypeSpecOwned())
9689 Decls.push_back(DS.getRepAsDecl());
9691 DeclaratorDecl *FirstDeclaratorInGroup = nullptr;
9692 for (unsigned i = 0, e = Group.size(); i != e; ++i)
9693 if (Decl *D = Group[i]) {
9694 if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D))
9695 if (!FirstDeclaratorInGroup)
9696 FirstDeclaratorInGroup = DD;
9700 if (DeclSpec::isDeclRep(DS.getTypeSpecType())) {
9701 if (TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) {
9702 HandleTagNumbering(*this, Tag, S);
9703 if (!Tag->hasNameForLinkage() && !Tag->hasDeclaratorForAnonDecl())
9704 Tag->setDeclaratorForAnonDecl(FirstDeclaratorInGroup);
9708 return BuildDeclaratorGroup(Decls, DS.containsPlaceholderType());
9711 /// BuildDeclaratorGroup - convert a list of declarations into a declaration
9712 /// group, performing any necessary semantic checking.
9713 Sema::DeclGroupPtrTy
9714 Sema::BuildDeclaratorGroup(MutableArrayRef<Decl *> Group,
9715 bool TypeMayContainAuto) {
9716 // C++0x [dcl.spec.auto]p7:
9717 // If the type deduced for the template parameter U is not the same in each
9718 // deduction, the program is ill-formed.
9719 // FIXME: When initializer-list support is added, a distinction is needed
9720 // between the deduced type U and the deduced type which 'auto' stands for.
9721 // auto a = 0, b = { 1, 2, 3 };
9722 // is legal because the deduced type U is 'int' in both cases.
9723 if (TypeMayContainAuto && Group.size() > 1) {
9725 CanQualType DeducedCanon;
9726 VarDecl *DeducedDecl = nullptr;
9727 for (unsigned i = 0, e = Group.size(); i != e; ++i) {
9728 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) {
9729 AutoType *AT = D->getType()->getContainedAutoType();
9730 // Don't reissue diagnostics when instantiating a template.
9731 if (AT && D->isInvalidDecl())
9733 QualType U = AT ? AT->getDeducedType() : QualType();
9735 CanQualType UCanon = Context.getCanonicalType(U);
9736 if (Deduced.isNull()) {
9738 DeducedCanon = UCanon;
9740 } else if (DeducedCanon != UCanon) {
9741 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(),
9742 diag::err_auto_different_deductions)
9743 << (AT->isDecltypeAuto() ? 1 : 0)
9744 << Deduced << DeducedDecl->getDeclName()
9745 << U << D->getDeclName()
9746 << DeducedDecl->getInit()->getSourceRange()
9747 << D->getInit()->getSourceRange();
9748 D->setInvalidDecl();
9756 ActOnDocumentableDecls(Group);
9758 return DeclGroupPtrTy::make(
9759 DeclGroupRef::Create(Context, Group.data(), Group.size()));
9762 void Sema::ActOnDocumentableDecl(Decl *D) {
9763 ActOnDocumentableDecls(D);
9766 void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) {
9767 // Don't parse the comment if Doxygen diagnostics are ignored.
9768 if (Group.empty() || !Group[0])
9771 if (Diags.isIgnored(diag::warn_doc_param_not_found, Group[0]->getLocation()))
9774 if (Group.size() >= 2) {
9775 // This is a decl group. Normally it will contain only declarations
9776 // produced from declarator list. But in case we have any definitions or
9777 // additional declaration references:
9778 // 'typedef struct S {} S;'
9779 // 'typedef struct S *S;'
9781 // FinalizeDeclaratorGroup adds these as separate declarations.
9782 Decl *MaybeTagDecl = Group[0];
9783 if (MaybeTagDecl && isa<TagDecl>(MaybeTagDecl)) {
9784 Group = Group.slice(1);
9788 // See if there are any new comments that are not attached to a decl.
9789 ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments();
9790 if (!Comments.empty() &&
9791 !Comments.back()->isAttached()) {
9792 // There is at least one comment that not attached to a decl.
9793 // Maybe it should be attached to one of these decls?
9795 // Note that this way we pick up not only comments that precede the
9796 // declaration, but also comments that *follow* the declaration -- thanks to
9797 // the lookahead in the lexer: we've consumed the semicolon and looked
9798 // ahead through comments.
9799 for (unsigned i = 0, e = Group.size(); i != e; ++i)
9800 Context.getCommentForDecl(Group[i], &PP);
9804 /// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator()
9805 /// to introduce parameters into function prototype scope.
9806 Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) {
9807 const DeclSpec &DS = D.getDeclSpec();
9809 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'.
9811 // C++03 [dcl.stc]p2 also permits 'auto'.
9812 StorageClass SC = SC_None;
9813 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
9815 } else if (getLangOpts().CPlusPlus &&
9816 DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
9818 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) {
9819 Diag(DS.getStorageClassSpecLoc(),
9820 diag::err_invalid_storage_class_in_func_decl);
9821 D.getMutableDeclSpec().ClearStorageClassSpecs();
9824 if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec())
9825 Diag(DS.getThreadStorageClassSpecLoc(), diag::err_invalid_thread)
9826 << DeclSpec::getSpecifierName(TSCS);
9827 if (DS.isConstexprSpecified())
9828 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr)
9831 DiagnoseFunctionSpecifiers(DS);
9833 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
9834 QualType parmDeclType = TInfo->getType();
9836 if (getLangOpts().CPlusPlus) {
9837 // Check that there are no default arguments inside the type of this
9839 CheckExtraCXXDefaultArguments(D);
9841 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
9842 if (D.getCXXScopeSpec().isSet()) {
9843 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator)
9844 << D.getCXXScopeSpec().getRange();
9845 D.getCXXScopeSpec().clear();
9849 // Ensure we have a valid name
9850 IdentifierInfo *II = nullptr;
9852 II = D.getIdentifier();
9854 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name)
9855 << GetNameForDeclarator(D).getName();
9856 D.setInvalidType(true);
9860 // Check for redeclaration of parameters, e.g. int foo(int x, int x);
9862 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName,
9865 if (R.isSingleResult()) {
9866 NamedDecl *PrevDecl = R.getFoundDecl();
9867 if (PrevDecl->isTemplateParameter()) {
9868 // Maybe we will complain about the shadowed template parameter.
9869 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
9870 // Just pretend that we didn't see the previous declaration.
9872 } else if (S->isDeclScope(PrevDecl)) {
9873 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II;
9874 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
9876 // Recover by removing the name
9878 D.SetIdentifier(nullptr, D.getIdentifierLoc());
9879 D.setInvalidType(true);
9884 // Temporarily put parameter variables in the translation unit, not
9885 // the enclosing context. This prevents them from accidentally
9886 // looking like class members in C++.
9887 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(),
9889 D.getIdentifierLoc(), II,
9890 parmDeclType, TInfo,
9893 if (D.isInvalidType())
9894 New->setInvalidDecl();
9896 assert(S->isFunctionPrototypeScope());
9897 assert(S->getFunctionPrototypeDepth() >= 1);
9898 New->setScopeInfo(S->getFunctionPrototypeDepth() - 1,
9899 S->getNextFunctionPrototypeIndex());
9901 // Add the parameter declaration into this scope.
9904 IdResolver.AddDecl(New);
9906 ProcessDeclAttributes(S, New, D);
9908 if (D.getDeclSpec().isModulePrivateSpecified())
9909 Diag(New->getLocation(), diag::err_module_private_local)
9910 << 1 << New->getDeclName()
9911 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
9912 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
9914 if (New->hasAttr<BlocksAttr>()) {
9915 Diag(New->getLocation(), diag::err_block_on_nonlocal);
9920 /// \brief Synthesizes a variable for a parameter arising from a
9922 ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC,
9925 /* FIXME: setting StartLoc == Loc.
9926 Would it be worth to modify callers so as to provide proper source
9927 location for the unnamed parameters, embedding the parameter's type? */
9928 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, nullptr,
9929 T, Context.getTrivialTypeSourceInfo(T, Loc),
9931 Param->setImplicit();
9935 void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param,
9936 ParmVarDecl * const *ParamEnd) {
9937 // Don't diagnose unused-parameter errors in template instantiations; we
9938 // will already have done so in the template itself.
9939 if (!ActiveTemplateInstantiations.empty())
9942 for (; Param != ParamEnd; ++Param) {
9943 if (!(*Param)->isReferenced() && (*Param)->getDeclName() &&
9944 !(*Param)->hasAttr<UnusedAttr>()) {
9945 Diag((*Param)->getLocation(), diag::warn_unused_parameter)
9946 << (*Param)->getDeclName();
9951 void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param,
9952 ParmVarDecl * const *ParamEnd,
9955 if (LangOpts.NumLargeByValueCopy == 0) // No check.
9958 // Warn if the return value is pass-by-value and larger than the specified
9960 if (!ReturnTy->isDependentType() && ReturnTy.isPODType(Context)) {
9961 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity();
9962 if (Size > LangOpts.NumLargeByValueCopy)
9963 Diag(D->getLocation(), diag::warn_return_value_size)
9964 << D->getDeclName() << Size;
9967 // Warn if any parameter is pass-by-value and larger than the specified
9969 for (; Param != ParamEnd; ++Param) {
9970 QualType T = (*Param)->getType();
9971 if (T->isDependentType() || !T.isPODType(Context))
9973 unsigned Size = Context.getTypeSizeInChars(T).getQuantity();
9974 if (Size > LangOpts.NumLargeByValueCopy)
9975 Diag((*Param)->getLocation(), diag::warn_parameter_size)
9976 << (*Param)->getDeclName() << Size;
9980 ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc,
9981 SourceLocation NameLoc, IdentifierInfo *Name,
9982 QualType T, TypeSourceInfo *TSInfo,
9984 // In ARC, infer a lifetime qualifier for appropriate parameter types.
9985 if (getLangOpts().ObjCAutoRefCount &&
9986 T.getObjCLifetime() == Qualifiers::OCL_None &&
9987 T->isObjCLifetimeType()) {
9989 Qualifiers::ObjCLifetime lifetime;
9991 // Special cases for arrays:
9992 // - if it's const, use __unsafe_unretained
9993 // - otherwise, it's an error
9994 if (T->isArrayType()) {
9995 if (!T.isConstQualified()) {
9996 DelayedDiagnostics.add(
9997 sema::DelayedDiagnostic::makeForbiddenType(
9998 NameLoc, diag::err_arc_array_param_no_ownership, T, false));
10000 lifetime = Qualifiers::OCL_ExplicitNone;
10002 lifetime = T->getObjCARCImplicitLifetime();
10004 T = Context.getLifetimeQualifiedType(T, lifetime);
10007 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name,
10008 Context.getAdjustedParameterType(T),
10009 TSInfo, SC, nullptr);
10011 // Parameters can not be abstract class types.
10012 // For record types, this is done by the AbstractClassUsageDiagnoser once
10013 // the class has been completely parsed.
10014 if (!CurContext->isRecord() &&
10015 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl,
10016 AbstractParamType))
10017 New->setInvalidDecl();
10019 // Parameter declarators cannot be interface types. All ObjC objects are
10020 // passed by reference.
10021 if (T->isObjCObjectType()) {
10022 SourceLocation TypeEndLoc = TSInfo->getTypeLoc().getLocEnd();
10024 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T
10025 << FixItHint::CreateInsertion(TypeEndLoc, "*");
10026 T = Context.getObjCObjectPointerType(T);
10030 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
10031 // duration shall not be qualified by an address-space qualifier."
10032 // Since all parameters have automatic store duration, they can not have
10033 // an address space.
10034 if (T.getAddressSpace() != 0) {
10035 // OpenCL allows function arguments declared to be an array of a type
10036 // to be qualified with an address space.
10037 if (!(getLangOpts().OpenCL && T->isArrayType())) {
10038 Diag(NameLoc, diag::err_arg_with_address_space);
10039 New->setInvalidDecl();
10046 void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
10047 SourceLocation LocAfterDecls) {
10048 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
10050 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared'
10051 // for a K&R function.
10052 if (!FTI.hasPrototype) {
10053 for (int i = FTI.NumParams; i != 0; /* decrement in loop */) {
10055 if (FTI.Params[i].Param == nullptr) {
10056 SmallString<256> Code;
10057 llvm::raw_svector_ostream(Code)
10058 << " int " << FTI.Params[i].Ident->getName() << ";\n";
10059 Diag(FTI.Params[i].IdentLoc, diag::ext_param_not_declared)
10060 << FTI.Params[i].Ident
10061 << FixItHint::CreateInsertion(LocAfterDecls, Code.str());
10063 // Implicitly declare the argument as type 'int' for lack of a better
10065 AttributeFactory attrs;
10066 DeclSpec DS(attrs);
10067 const char* PrevSpec; // unused
10068 unsigned DiagID; // unused
10069 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.Params[i].IdentLoc, PrevSpec,
10070 DiagID, Context.getPrintingPolicy());
10071 // Use the identifier location for the type source range.
10072 DS.SetRangeStart(FTI.Params[i].IdentLoc);
10073 DS.SetRangeEnd(FTI.Params[i].IdentLoc);
10074 Declarator ParamD(DS, Declarator::KNRTypeListContext);
10075 ParamD.SetIdentifier(FTI.Params[i].Ident, FTI.Params[i].IdentLoc);
10076 FTI.Params[i].Param = ActOnParamDeclarator(S, ParamD);
10082 Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) {
10083 assert(getCurFunctionDecl() == nullptr && "Function parsing confused");
10084 assert(D.isFunctionDeclarator() && "Not a function declarator!");
10085 Scope *ParentScope = FnBodyScope->getParent();
10087 D.setFunctionDefinitionKind(FDK_Definition);
10088 Decl *DP = HandleDeclarator(ParentScope, D, MultiTemplateParamsArg());
10089 return ActOnStartOfFunctionDef(FnBodyScope, DP);
10092 void Sema::ActOnFinishInlineMethodDef(CXXMethodDecl *D) {
10093 Consumer.HandleInlineMethodDefinition(D);
10096 static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD,
10097 const FunctionDecl*& PossibleZeroParamPrototype) {
10098 // Don't warn about invalid declarations.
10099 if (FD->isInvalidDecl())
10102 // Or declarations that aren't global.
10103 if (!FD->isGlobal())
10106 // Don't warn about C++ member functions.
10107 if (isa<CXXMethodDecl>(FD))
10110 // Don't warn about 'main'.
10114 // Don't warn about inline functions.
10115 if (FD->isInlined())
10118 // Don't warn about function templates.
10119 if (FD->getDescribedFunctionTemplate())
10122 // Don't warn about function template specializations.
10123 if (FD->isFunctionTemplateSpecialization())
10126 // Don't warn for OpenCL kernels.
10127 if (FD->hasAttr<OpenCLKernelAttr>())
10130 bool MissingPrototype = true;
10131 for (const FunctionDecl *Prev = FD->getPreviousDecl();
10132 Prev; Prev = Prev->getPreviousDecl()) {
10133 // Ignore any declarations that occur in function or method
10134 // scope, because they aren't visible from the header.
10135 if (Prev->getLexicalDeclContext()->isFunctionOrMethod())
10138 MissingPrototype = !Prev->getType()->isFunctionProtoType();
10139 if (FD->getNumParams() == 0)
10140 PossibleZeroParamPrototype = Prev;
10144 return MissingPrototype;
10148 Sema::CheckForFunctionRedefinition(FunctionDecl *FD,
10149 const FunctionDecl *EffectiveDefinition) {
10150 // Don't complain if we're in GNU89 mode and the previous definition
10151 // was an extern inline function.
10152 const FunctionDecl *Definition = EffectiveDefinition;
10154 if (!FD->isDefined(Definition))
10157 if (canRedefineFunction(Definition, getLangOpts()))
10160 if (getLangOpts().GNUMode && Definition->isInlineSpecified() &&
10161 Definition->getStorageClass() == SC_Extern)
10162 Diag(FD->getLocation(), diag::err_redefinition_extern_inline)
10163 << FD->getDeclName() << getLangOpts().CPlusPlus;
10165 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName();
10167 Diag(Definition->getLocation(), diag::note_previous_definition);
10168 FD->setInvalidDecl();
10172 static void RebuildLambdaScopeInfo(CXXMethodDecl *CallOperator,
10174 CXXRecordDecl *const LambdaClass = CallOperator->getParent();
10176 LambdaScopeInfo *LSI = S.PushLambdaScope();
10177 LSI->CallOperator = CallOperator;
10178 LSI->Lambda = LambdaClass;
10179 LSI->ReturnType = CallOperator->getReturnType();
10180 const LambdaCaptureDefault LCD = LambdaClass->getLambdaCaptureDefault();
10182 if (LCD == LCD_None)
10183 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_None;
10184 else if (LCD == LCD_ByCopy)
10185 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByval;
10186 else if (LCD == LCD_ByRef)
10187 LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByref;
10188 DeclarationNameInfo DNI = CallOperator->getNameInfo();
10190 LSI->IntroducerRange = DNI.getCXXOperatorNameRange();
10191 LSI->Mutable = !CallOperator->isConst();
10193 // Add the captures to the LSI so they can be noted as already
10194 // captured within tryCaptureVar.
10195 auto I = LambdaClass->field_begin();
10196 for (const auto &C : LambdaClass->captures()) {
10197 if (C.capturesVariable()) {
10198 VarDecl *VD = C.getCapturedVar();
10199 if (VD->isInitCapture())
10200 S.CurrentInstantiationScope->InstantiatedLocal(VD, VD);
10201 QualType CaptureType = VD->getType();
10202 const bool ByRef = C.getCaptureKind() == LCK_ByRef;
10203 LSI->addCapture(VD, /*IsBlock*/false, ByRef,
10204 /*RefersToEnclosingVariableOrCapture*/true, C.getLocation(),
10205 /*EllipsisLoc*/C.isPackExpansion()
10206 ? C.getEllipsisLoc() : SourceLocation(),
10207 CaptureType, /*Expr*/ nullptr);
10209 } else if (C.capturesThis()) {
10210 LSI->addThisCapture(/*Nested*/ false, C.getLocation(),
10211 S.getCurrentThisType(), /*Expr*/ nullptr);
10213 LSI->addVLATypeCapture(C.getLocation(), I->getType());
10219 Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) {
10220 // Clear the last template instantiation error context.
10221 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation();
10225 FunctionDecl *FD = nullptr;
10227 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D))
10228 FD = FunTmpl->getTemplatedDecl();
10230 FD = cast<FunctionDecl>(D);
10231 // If we are instantiating a generic lambda call operator, push
10232 // a LambdaScopeInfo onto the function stack. But use the information
10233 // that's already been calculated (ActOnLambdaExpr) to prime the current
10234 // LambdaScopeInfo.
10235 // When the template operator is being specialized, the LambdaScopeInfo,
10236 // has to be properly restored so that tryCaptureVariable doesn't try
10237 // and capture any new variables. In addition when calculating potential
10238 // captures during transformation of nested lambdas, it is necessary to
10239 // have the LSI properly restored.
10240 if (isGenericLambdaCallOperatorSpecialization(FD)) {
10241 assert(ActiveTemplateInstantiations.size() &&
10242 "There should be an active template instantiation on the stack "
10243 "when instantiating a generic lambda!");
10244 RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this);
10247 // Enter a new function scope
10248 PushFunctionScope();
10250 // See if this is a redefinition.
10251 if (!FD->isLateTemplateParsed())
10252 CheckForFunctionRedefinition(FD);
10254 // Builtin functions cannot be defined.
10255 if (unsigned BuiltinID = FD->getBuiltinID()) {
10256 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) &&
10257 !Context.BuiltinInfo.isPredefinedRuntimeFunction(BuiltinID)) {
10258 Diag(FD->getLocation(), diag::err_builtin_definition) << FD;
10259 FD->setInvalidDecl();
10263 // The return type of a function definition must be complete
10264 // (C99 6.9.1p3, C++ [dcl.fct]p6).
10265 QualType ResultType = FD->getReturnType();
10266 if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
10267 !FD->isInvalidDecl() &&
10268 RequireCompleteType(FD->getLocation(), ResultType,
10269 diag::err_func_def_incomplete_result))
10270 FD->setInvalidDecl();
10272 // GNU warning -Wmissing-prototypes:
10273 // Warn if a global function is defined without a previous
10274 // prototype declaration. This warning is issued even if the
10275 // definition itself provides a prototype. The aim is to detect
10276 // global functions that fail to be declared in header files.
10277 const FunctionDecl *PossibleZeroParamPrototype = nullptr;
10278 if (ShouldWarnAboutMissingPrototype(FD, PossibleZeroParamPrototype)) {
10279 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD;
10281 if (PossibleZeroParamPrototype) {
10282 // We found a declaration that is not a prototype,
10283 // but that could be a zero-parameter prototype
10284 if (TypeSourceInfo *TI =
10285 PossibleZeroParamPrototype->getTypeSourceInfo()) {
10286 TypeLoc TL = TI->getTypeLoc();
10287 if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>())
10288 Diag(PossibleZeroParamPrototype->getLocation(),
10289 diag::note_declaration_not_a_prototype)
10290 << PossibleZeroParamPrototype
10291 << FixItHint::CreateInsertion(FTL.getRParenLoc(), "void");
10297 PushDeclContext(FnBodyScope, FD);
10299 // Check the validity of our function parameters
10300 CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(),
10301 /*CheckParameterNames=*/true);
10303 // Introduce our parameters into the function scope
10304 for (auto Param : FD->params()) {
10305 Param->setOwningFunction(FD);
10307 // If this has an identifier, add it to the scope stack.
10308 if (Param->getIdentifier() && FnBodyScope) {
10309 CheckShadow(FnBodyScope, Param);
10311 PushOnScopeChains(Param, FnBodyScope);
10315 // If we had any tags defined in the function prototype,
10316 // introduce them into the function scope.
10318 for (ArrayRef<NamedDecl *>::iterator
10319 I = FD->getDeclsInPrototypeScope().begin(),
10320 E = FD->getDeclsInPrototypeScope().end();
10324 // Some of these decls (like enums) may have been pinned to the translation unit
10325 // for lack of a real context earlier. If so, remove from the translation unit
10326 // and reattach to the current context.
10327 if (D->getLexicalDeclContext() == Context.getTranslationUnitDecl()) {
10328 // Is the decl actually in the context?
10329 for (const auto *DI : Context.getTranslationUnitDecl()->decls()) {
10331 Context.getTranslationUnitDecl()->removeDecl(D);
10335 // Either way, reassign the lexical decl context to our FunctionDecl.
10336 D->setLexicalDeclContext(CurContext);
10339 // If the decl has a non-null name, make accessible in the current scope.
10340 if (!D->getName().empty())
10341 PushOnScopeChains(D, FnBodyScope, /*AddToContext=*/false);
10343 // Similarly, dive into enums and fish their constants out, making them
10344 // accessible in this scope.
10345 if (auto *ED = dyn_cast<EnumDecl>(D)) {
10346 for (auto *EI : ED->enumerators())
10347 PushOnScopeChains(EI, FnBodyScope, /*AddToContext=*/false);
10352 // Ensure that the function's exception specification is instantiated.
10353 if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>())
10354 ResolveExceptionSpec(D->getLocation(), FPT);
10356 // dllimport cannot be applied to non-inline function definitions.
10357 if (FD->hasAttr<DLLImportAttr>() && !FD->isInlined() &&
10358 !FD->isTemplateInstantiation()) {
10359 assert(!FD->hasAttr<DLLExportAttr>());
10360 Diag(FD->getLocation(), diag::err_attribute_dllimport_function_definition);
10361 FD->setInvalidDecl();
10364 // We want to attach documentation to original Decl (which might be
10365 // a function template).
10366 ActOnDocumentableDecl(D);
10367 if (getCurLexicalContext()->isObjCContainer() &&
10368 getCurLexicalContext()->getDeclKind() != Decl::ObjCCategoryImpl &&
10369 getCurLexicalContext()->getDeclKind() != Decl::ObjCImplementation)
10370 Diag(FD->getLocation(), diag::warn_function_def_in_objc_container);
10375 /// \brief Given the set of return statements within a function body,
10376 /// compute the variables that are subject to the named return value
10379 /// Each of the variables that is subject to the named return value
10380 /// optimization will be marked as NRVO variables in the AST, and any
10381 /// return statement that has a marked NRVO variable as its NRVO candidate can
10382 /// use the named return value optimization.
10384 /// This function applies a very simplistic algorithm for NRVO: if every return
10385 /// statement in the scope of a variable has the same NRVO candidate, that
10386 /// candidate is an NRVO variable.
10387 void Sema::computeNRVO(Stmt *Body, FunctionScopeInfo *Scope) {
10388 ReturnStmt **Returns = Scope->Returns.data();
10390 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) {
10391 if (const VarDecl *NRVOCandidate = Returns[I]->getNRVOCandidate()) {
10392 if (!NRVOCandidate->isNRVOVariable())
10393 Returns[I]->setNRVOCandidate(nullptr);
10398 bool Sema::canDelayFunctionBody(const Declarator &D) {
10399 // We can't delay parsing the body of a constexpr function template (yet).
10400 if (D.getDeclSpec().isConstexprSpecified())
10403 // We can't delay parsing the body of a function template with a deduced
10404 // return type (yet).
10405 if (D.getDeclSpec().containsPlaceholderType()) {
10406 // If the placeholder introduces a non-deduced trailing return type,
10407 // we can still delay parsing it.
10408 if (D.getNumTypeObjects()) {
10409 const auto &Outer = D.getTypeObject(D.getNumTypeObjects() - 1);
10410 if (Outer.Kind == DeclaratorChunk::Function &&
10411 Outer.Fun.hasTrailingReturnType()) {
10412 QualType Ty = GetTypeFromParser(Outer.Fun.getTrailingReturnType());
10413 return Ty.isNull() || !Ty->isUndeducedType();
10422 bool Sema::canSkipFunctionBody(Decl *D) {
10423 // We cannot skip the body of a function (or function template) which is
10424 // constexpr, since we may need to evaluate its body in order to parse the
10425 // rest of the file.
10426 // We cannot skip the body of a function with an undeduced return type,
10427 // because any callers of that function need to know the type.
10428 if (const FunctionDecl *FD = D->getAsFunction())
10429 if (FD->isConstexpr() || FD->getReturnType()->isUndeducedType())
10431 return Consumer.shouldSkipFunctionBody(D);
10434 Decl *Sema::ActOnSkippedFunctionBody(Decl *Decl) {
10435 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Decl))
10436 FD->setHasSkippedBody();
10437 else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(Decl))
10438 MD->setHasSkippedBody();
10439 return ActOnFinishFunctionBody(Decl, nullptr);
10442 Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) {
10443 return ActOnFinishFunctionBody(D, BodyArg, false);
10446 Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
10447 bool IsInstantiation) {
10448 FunctionDecl *FD = dcl ? dcl->getAsFunction() : nullptr;
10450 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
10451 sema::AnalysisBasedWarnings::Policy *ActivePolicy = nullptr;
10456 if (getLangOpts().CPlusPlus14 && !FD->isInvalidDecl() && Body &&
10457 !FD->isDependentContext() && FD->getReturnType()->isUndeducedType()) {
10458 // If the function has a deduced result type but contains no 'return'
10459 // statements, the result type as written must be exactly 'auto', and
10460 // the deduced result type is 'void'.
10461 if (!FD->getReturnType()->getAs<AutoType>()) {
10462 Diag(dcl->getLocation(), diag::err_auto_fn_no_return_but_not_auto)
10463 << FD->getReturnType();
10464 FD->setInvalidDecl();
10466 // Substitute 'void' for the 'auto' in the type.
10467 TypeLoc ResultType = getReturnTypeLoc(FD);
10468 Context.adjustDeducedFunctionResultType(
10469 FD, SubstAutoType(ResultType.getType(), Context.VoidTy));
10473 // The only way to be included in UndefinedButUsed is if there is an
10474 // ODR use before the definition. Avoid the expensive map lookup if this
10475 // is the first declaration.
10476 if (!FD->isFirstDecl() && FD->getPreviousDecl()->isUsed()) {
10477 if (!FD->isExternallyVisible())
10478 UndefinedButUsed.erase(FD);
10479 else if (FD->isInlined() &&
10480 (LangOpts.CPlusPlus || !LangOpts.GNUInline) &&
10481 (!FD->getPreviousDecl()->hasAttr<GNUInlineAttr>()))
10482 UndefinedButUsed.erase(FD);
10485 // If the function implicitly returns zero (like 'main') or is naked,
10486 // don't complain about missing return statements.
10487 if (FD->hasImplicitReturnZero() || FD->hasAttr<NakedAttr>())
10488 WP.disableCheckFallThrough();
10490 // MSVC permits the use of pure specifier (=0) on function definition,
10491 // defined at class scope, warn about this non-standard construct.
10492 if (getLangOpts().MicrosoftExt && FD->isPure() && FD->isCanonicalDecl())
10493 Diag(FD->getLocation(), diag::ext_pure_function_definition);
10495 if (!FD->isInvalidDecl()) {
10496 // Don't diagnose unused parameters of defaulted or deleted functions.
10498 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end());
10499 DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(),
10500 FD->getReturnType(), FD);
10502 // If this is a structor, we need a vtable.
10503 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD))
10504 MarkVTableUsed(FD->getLocation(), Constructor->getParent());
10505 else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(FD))
10506 MarkVTableUsed(FD->getLocation(), Destructor->getParent());
10508 // Try to apply the named return value optimization. We have to check
10509 // if we can do this here because lambdas keep return statements around
10510 // to deduce an implicit return type.
10511 if (getLangOpts().CPlusPlus && FD->getReturnType()->isRecordType() &&
10512 !FD->isDependentContext())
10513 computeNRVO(Body, getCurFunction());
10516 assert((FD == getCurFunctionDecl() || getCurLambda()->CallOperator == FD) &&
10517 "Function parsing confused");
10518 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) {
10519 assert(MD == getCurMethodDecl() && "Method parsing confused");
10521 if (!MD->isInvalidDecl()) {
10522 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end());
10523 DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(),
10524 MD->getReturnType(), MD);
10527 computeNRVO(Body, getCurFunction());
10529 if (getCurFunction()->ObjCShouldCallSuper) {
10530 Diag(MD->getLocEnd(), diag::warn_objc_missing_super_call)
10531 << MD->getSelector().getAsString();
10532 getCurFunction()->ObjCShouldCallSuper = false;
10534 if (getCurFunction()->ObjCWarnForNoDesignatedInitChain) {
10535 const ObjCMethodDecl *InitMethod = nullptr;
10536 bool isDesignated =
10537 MD->isDesignatedInitializerForTheInterface(&InitMethod);
10538 assert(isDesignated && InitMethod);
10539 (void)isDesignated;
10541 auto superIsNSObject = [&](const ObjCMethodDecl *MD) {
10542 auto IFace = MD->getClassInterface();
10545 auto SuperD = IFace->getSuperClass();
10548 return SuperD->getIdentifier() ==
10549 NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject);
10551 // Don't issue this warning for unavailable inits or direct subclasses
10553 if (!MD->isUnavailable() && !superIsNSObject(MD)) {
10554 Diag(MD->getLocation(),
10555 diag::warn_objc_designated_init_missing_super_call);
10556 Diag(InitMethod->getLocation(),
10557 diag::note_objc_designated_init_marked_here);
10559 getCurFunction()->ObjCWarnForNoDesignatedInitChain = false;
10561 if (getCurFunction()->ObjCWarnForNoInitDelegation) {
10562 // Don't issue this warning for unavaialable inits.
10563 if (!MD->isUnavailable())
10564 Diag(MD->getLocation(), diag::warn_objc_secondary_init_missing_init_call);
10565 getCurFunction()->ObjCWarnForNoInitDelegation = false;
10571 assert(!getCurFunction()->ObjCShouldCallSuper &&
10572 "This should only be set for ObjC methods, which should have been "
10573 "handled in the block above.");
10575 // Verify and clean out per-function state.
10577 // C++ constructors that have function-try-blocks can't have return
10578 // statements in the handlers of that block. (C++ [except.handle]p14)
10580 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body))
10581 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body));
10583 // Verify that gotos and switch cases don't jump into scopes illegally.
10584 if (getCurFunction()->NeedsScopeChecking() &&
10585 !PP.isCodeCompletionEnabled())
10586 DiagnoseInvalidJumps(Body);
10588 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) {
10589 if (!Destructor->getParent()->isDependentType())
10590 CheckDestructor(Destructor);
10592 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
10593 Destructor->getParent());
10596 // If any errors have occurred, clear out any temporaries that may have
10597 // been leftover. This ensures that these temporaries won't be picked up for
10598 // deletion in some later function.
10599 if (getDiagnostics().hasErrorOccurred() ||
10600 getDiagnostics().getSuppressAllDiagnostics()) {
10601 DiscardCleanupsInEvaluationContext();
10603 if (!getDiagnostics().hasUncompilableErrorOccurred() &&
10604 !isa<FunctionTemplateDecl>(dcl)) {
10605 // Since the body is valid, issue any analysis-based warnings that are
10607 ActivePolicy = &WP;
10610 if (!IsInstantiation && FD && FD->isConstexpr() && !FD->isInvalidDecl() &&
10611 (!CheckConstexprFunctionDecl(FD) ||
10612 !CheckConstexprFunctionBody(FD, Body)))
10613 FD->setInvalidDecl();
10615 if (FD && FD->hasAttr<NakedAttr>()) {
10616 for (const Stmt *S : Body->children()) {
10617 if (!isa<AsmStmt>(S) && !isa<NullStmt>(S)) {
10618 Diag(S->getLocStart(), diag::err_non_asm_stmt_in_naked_function);
10619 Diag(FD->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
10620 FD->setInvalidDecl();
10626 assert(ExprCleanupObjects.size() == ExprEvalContexts.back().NumCleanupObjects
10627 && "Leftover temporaries in function");
10628 assert(!ExprNeedsCleanups && "Unaccounted cleanups in function");
10629 assert(MaybeODRUseExprs.empty() &&
10630 "Leftover expressions for odr-use checking");
10633 if (!IsInstantiation)
10636 PopFunctionScopeInfo(ActivePolicy, dcl);
10637 // If any errors have occurred, clear out any temporaries that may have
10638 // been leftover. This ensures that these temporaries won't be picked up for
10639 // deletion in some later function.
10640 if (getDiagnostics().hasErrorOccurred()) {
10641 DiscardCleanupsInEvaluationContext();
10648 /// When we finish delayed parsing of an attribute, we must attach it to the
10650 void Sema::ActOnFinishDelayedAttribute(Scope *S, Decl *D,
10651 ParsedAttributes &Attrs) {
10652 // Always attach attributes to the underlying decl.
10653 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
10654 D = TD->getTemplatedDecl();
10655 ProcessDeclAttributeList(S, D, Attrs.getList());
10657 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(D))
10658 if (Method->isStatic())
10659 checkThisInStaticMemberFunctionAttributes(Method);
10663 /// ImplicitlyDefineFunction - An undeclared identifier was used in a function
10664 /// call, forming a call to an implicitly defined function (per C99 6.5.1p2).
10665 NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
10666 IdentifierInfo &II, Scope *S) {
10667 // Before we produce a declaration for an implicitly defined
10668 // function, see whether there was a locally-scoped declaration of
10669 // this name as a function or variable. If so, use that
10670 // (non-visible) declaration, and complain about it.
10671 if (NamedDecl *ExternCPrev = findLocallyScopedExternCDecl(&II)) {
10672 Diag(Loc, diag::warn_use_out_of_scope_declaration) << ExternCPrev;
10673 Diag(ExternCPrev->getLocation(), diag::note_previous_declaration);
10674 return ExternCPrev;
10677 // Extension in C99. Legal in C90, but warn about it.
10679 if (II.getName().startswith("__builtin_"))
10680 diag_id = diag::warn_builtin_unknown;
10681 else if (getLangOpts().C99)
10682 diag_id = diag::ext_implicit_function_decl;
10684 diag_id = diag::warn_implicit_function_decl;
10685 Diag(Loc, diag_id) << &II;
10687 // Because typo correction is expensive, only do it if the implicit
10688 // function declaration is going to be treated as an error.
10689 if (Diags.getDiagnosticLevel(diag_id, Loc) >= DiagnosticsEngine::Error) {
10690 TypoCorrection Corrected;
10692 (Corrected = CorrectTypo(
10693 DeclarationNameInfo(&II, Loc), LookupOrdinaryName, S, nullptr,
10694 llvm::make_unique<DeclFilterCCC<FunctionDecl>>(), CTK_NonError)))
10695 diagnoseTypo(Corrected, PDiag(diag::note_function_suggestion),
10696 /*ErrorRecovery*/false);
10699 // Set a Declarator for the implicit definition: int foo();
10701 AttributeFactory attrFactory;
10702 DeclSpec DS(attrFactory);
10704 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID,
10705 Context.getPrintingPolicy());
10706 (void)Error; // Silence warning.
10707 assert(!Error && "Error setting up implicit decl!");
10708 SourceLocation NoLoc;
10709 Declarator D(DS, Declarator::BlockContext);
10710 D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false,
10711 /*IsAmbiguous=*/false,
10712 /*LParenLoc=*/NoLoc,
10713 /*Params=*/nullptr,
10715 /*EllipsisLoc=*/NoLoc,
10716 /*RParenLoc=*/NoLoc,
10718 /*RefQualifierIsLvalueRef=*/true,
10719 /*RefQualifierLoc=*/NoLoc,
10720 /*ConstQualifierLoc=*/NoLoc,
10721 /*VolatileQualifierLoc=*/NoLoc,
10722 /*RestrictQualifierLoc=*/NoLoc,
10723 /*MutableLoc=*/NoLoc,
10725 /*ESpecLoc=*/NoLoc,
10726 /*Exceptions=*/nullptr,
10727 /*ExceptionRanges=*/nullptr,
10728 /*NumExceptions=*/0,
10729 /*NoexceptExpr=*/nullptr,
10730 /*ExceptionSpecTokens=*/nullptr,
10732 DS.getAttributes(),
10734 D.SetIdentifier(&II, Loc);
10736 // Insert this function into translation-unit scope.
10738 DeclContext *PrevDC = CurContext;
10739 CurContext = Context.getTranslationUnitDecl();
10741 FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(TUScope, D));
10744 CurContext = PrevDC;
10746 AddKnownFunctionAttributes(FD);
10751 /// \brief Adds any function attributes that we know a priori based on
10752 /// the declaration of this function.
10754 /// These attributes can apply both to implicitly-declared builtins
10755 /// (like __builtin___printf_chk) or to library-declared functions
10756 /// like NSLog or printf.
10758 /// We need to check for duplicate attributes both here and where user-written
10759 /// attributes are applied to declarations.
10760 void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) {
10761 if (FD->isInvalidDecl())
10764 // If this is a built-in function, map its builtin attributes to
10765 // actual attributes.
10766 if (unsigned BuiltinID = FD->getBuiltinID()) {
10767 // Handle printf-formatting attributes.
10768 unsigned FormatIdx;
10770 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) {
10771 if (!FD->hasAttr<FormatAttr>()) {
10772 const char *fmt = "printf";
10773 unsigned int NumParams = FD->getNumParams();
10774 if (FormatIdx < NumParams && // NumParams may be 0 (e.g. vfprintf)
10775 FD->getParamDecl(FormatIdx)->getType()->isObjCObjectPointerType())
10777 FD->addAttr(FormatAttr::CreateImplicit(Context,
10778 &Context.Idents.get(fmt),
10780 HasVAListArg ? 0 : FormatIdx+2,
10781 FD->getLocation()));
10784 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx,
10786 if (!FD->hasAttr<FormatAttr>())
10787 FD->addAttr(FormatAttr::CreateImplicit(Context,
10788 &Context.Idents.get("scanf"),
10790 HasVAListArg ? 0 : FormatIdx+2,
10791 FD->getLocation()));
10794 // Mark const if we don't care about errno and that is the only
10795 // thing preventing the function from being const. This allows
10796 // IRgen to use LLVM intrinsics for such functions.
10797 if (!getLangOpts().MathErrno &&
10798 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) {
10799 if (!FD->hasAttr<ConstAttr>())
10800 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
10803 if (Context.BuiltinInfo.isReturnsTwice(BuiltinID) &&
10804 !FD->hasAttr<ReturnsTwiceAttr>())
10805 FD->addAttr(ReturnsTwiceAttr::CreateImplicit(Context,
10806 FD->getLocation()));
10807 if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->hasAttr<NoThrowAttr>())
10808 FD->addAttr(NoThrowAttr::CreateImplicit(Context, FD->getLocation()));
10809 if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->hasAttr<ConstAttr>())
10810 FD->addAttr(ConstAttr::CreateImplicit(Context, FD->getLocation()));
10813 IdentifierInfo *Name = FD->getIdentifier();
10816 if ((!getLangOpts().CPlusPlus &&
10817 FD->getDeclContext()->isTranslationUnit()) ||
10818 (isa<LinkageSpecDecl>(FD->getDeclContext()) &&
10819 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() ==
10820 LinkageSpecDecl::lang_c)) {
10821 // Okay: this could be a libc/libm/Objective-C function we know
10826 if (Name->isStr("asprintf") || Name->isStr("vasprintf")) {
10827 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be
10828 // target-specific builtins, perhaps?
10829 if (!FD->hasAttr<FormatAttr>())
10830 FD->addAttr(FormatAttr::CreateImplicit(Context,
10831 &Context.Idents.get("printf"), 2,
10832 Name->isStr("vasprintf") ? 0 : 3,
10833 FD->getLocation()));
10836 if (Name->isStr("__CFStringMakeConstantString")) {
10837 // We already have a __builtin___CFStringMakeConstantString,
10838 // but builds that use -fno-constant-cfstrings don't go through that.
10839 if (!FD->hasAttr<FormatArgAttr>())
10840 FD->addAttr(FormatArgAttr::CreateImplicit(Context, 1,
10841 FD->getLocation()));
10845 TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
10846 TypeSourceInfo *TInfo) {
10847 assert(D.getIdentifier() && "Wrong callback for declspec without declarator");
10848 assert(!T.isNull() && "GetTypeForDeclarator() returned null type");
10851 assert(D.isInvalidType() && "no declarator info for valid type");
10852 TInfo = Context.getTrivialTypeSourceInfo(T);
10855 // Scope manipulation handled by caller.
10856 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext,
10858 D.getIdentifierLoc(),
10862 // Bail out immediately if we have an invalid declaration.
10863 if (D.isInvalidType()) {
10864 NewTD->setInvalidDecl();
10868 if (D.getDeclSpec().isModulePrivateSpecified()) {
10869 if (CurContext->isFunctionOrMethod())
10870 Diag(NewTD->getLocation(), diag::err_module_private_local)
10871 << 2 << NewTD->getDeclName()
10872 << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc())
10873 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc());
10875 NewTD->setModulePrivate();
10878 // C++ [dcl.typedef]p8:
10879 // If the typedef declaration defines an unnamed class (or
10880 // enum), the first typedef-name declared by the declaration
10881 // to be that class type (or enum type) is used to denote the
10882 // class type (or enum type) for linkage purposes only.
10883 // We need to check whether the type was declared in the declaration.
10884 switch (D.getDeclSpec().getTypeSpecType()) {
10887 case TST_interface:
10890 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
10892 // Do nothing if the tag is not anonymous or already has an
10893 // associated typedef (from an earlier typedef in this decl group).
10894 if (tagFromDeclSpec->getIdentifier()) break;
10895 if (tagFromDeclSpec->getTypedefNameForAnonDecl()) break;
10897 // A well-formed anonymous tag must always be a TUK_Definition.
10898 assert(tagFromDeclSpec->isThisDeclarationADefinition());
10900 // The type must match the tag exactly; no qualifiers allowed.
10901 if (!Context.hasSameType(T, Context.getTagDeclType(tagFromDeclSpec)))
10904 // If we've already computed linkage for the anonymous tag, then
10905 // adding a typedef name for the anonymous decl can change that
10906 // linkage, which might be a serious problem. Diagnose this as
10907 // unsupported and ignore the typedef name. TODO: we should
10908 // pursue this as a language defect and establish a formal rule
10909 // for how to handle it.
10910 if (tagFromDeclSpec->hasLinkageBeenComputed()) {
10911 Diag(D.getIdentifierLoc(), diag::err_typedef_changes_linkage);
10913 SourceLocation tagLoc = D.getDeclSpec().getTypeSpecTypeLoc();
10914 tagLoc = getLocForEndOfToken(tagLoc);
10916 llvm::SmallString<40> textToInsert;
10917 textToInsert += ' ';
10918 textToInsert += D.getIdentifier()->getName();
10919 Diag(tagLoc, diag::note_typedef_changes_linkage)
10920 << FixItHint::CreateInsertion(tagLoc, textToInsert);
10924 // Otherwise, set this is the anon-decl typedef for the tag.
10925 tagFromDeclSpec->setTypedefNameForAnonDecl(NewTD);
10937 /// \brief Check that this is a valid underlying type for an enum declaration.
10938 bool Sema::CheckEnumUnderlyingType(TypeSourceInfo *TI) {
10939 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
10940 QualType T = TI->getType();
10942 if (T->isDependentType())
10945 if (const BuiltinType *BT = T->getAs<BuiltinType>())
10946 if (BT->isInteger())
10949 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) << T;
10953 /// Check whether this is a valid redeclaration of a previous enumeration.
10954 /// \return true if the redeclaration was invalid.
10955 bool Sema::CheckEnumRedeclaration(SourceLocation EnumLoc, bool IsScoped,
10956 QualType EnumUnderlyingTy,
10957 const EnumDecl *Prev) {
10958 bool IsFixed = !EnumUnderlyingTy.isNull();
10960 if (IsScoped != Prev->isScoped()) {
10961 Diag(EnumLoc, diag::err_enum_redeclare_scoped_mismatch)
10962 << Prev->isScoped();
10963 Diag(Prev->getLocation(), diag::note_previous_declaration);
10967 if (IsFixed && Prev->isFixed()) {
10968 if (!EnumUnderlyingTy->isDependentType() &&
10969 !Prev->getIntegerType()->isDependentType() &&
10970 !Context.hasSameUnqualifiedType(EnumUnderlyingTy,
10971 Prev->getIntegerType())) {
10972 // TODO: Highlight the underlying type of the redeclaration.
10973 Diag(EnumLoc, diag::err_enum_redeclare_type_mismatch)
10974 << EnumUnderlyingTy << Prev->getIntegerType();
10975 Diag(Prev->getLocation(), diag::note_previous_declaration)
10976 << Prev->getIntegerTypeRange();
10979 } else if (IsFixed != Prev->isFixed()) {
10980 Diag(EnumLoc, diag::err_enum_redeclare_fixed_mismatch)
10981 << Prev->isFixed();
10982 Diag(Prev->getLocation(), diag::note_previous_declaration);
10989 /// \brief Get diagnostic %select index for tag kind for
10990 /// redeclaration diagnostic message.
10991 /// WARNING: Indexes apply to particular diagnostics only!
10993 /// \returns diagnostic %select index.
10994 static unsigned getRedeclDiagFromTagKind(TagTypeKind Tag) {
10996 case TTK_Struct: return 0;
10997 case TTK_Interface: return 1;
10998 case TTK_Class: return 2;
10999 default: llvm_unreachable("Invalid tag kind for redecl diagnostic!");
11003 /// \brief Determine if tag kind is a class-key compatible with
11004 /// class for redeclaration (class, struct, or __interface).
11006 /// \returns true iff the tag kind is compatible.
11007 static bool isClassCompatTagKind(TagTypeKind Tag)
11009 return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface;
11012 /// \brief Determine whether a tag with a given kind is acceptable
11013 /// as a redeclaration of the given tag declaration.
11015 /// \returns true if the new tag kind is acceptable, false otherwise.
11016 bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous,
11017 TagTypeKind NewTag, bool isDefinition,
11018 SourceLocation NewTagLoc,
11019 const IdentifierInfo &Name) {
11020 // C++ [dcl.type.elab]p3:
11021 // The class-key or enum keyword present in the
11022 // elaborated-type-specifier shall agree in kind with the
11023 // declaration to which the name in the elaborated-type-specifier
11024 // refers. This rule also applies to the form of
11025 // elaborated-type-specifier that declares a class-name or
11026 // friend class since it can be construed as referring to the
11027 // definition of the class. Thus, in any
11028 // elaborated-type-specifier, the enum keyword shall be used to
11029 // refer to an enumeration (7.2), the union class-key shall be
11030 // used to refer to a union (clause 9), and either the class or
11031 // struct class-key shall be used to refer to a class (clause 9)
11032 // declared using the class or struct class-key.
11033 TagTypeKind OldTag = Previous->getTagKind();
11034 if (!isDefinition || !isClassCompatTagKind(NewTag))
11035 if (OldTag == NewTag)
11038 if (isClassCompatTagKind(OldTag) && isClassCompatTagKind(NewTag)) {
11039 // Warn about the struct/class tag mismatch.
11040 bool isTemplate = false;
11041 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous))
11042 isTemplate = Record->getDescribedClassTemplate();
11044 if (!ActiveTemplateInstantiations.empty()) {
11045 // In a template instantiation, do not offer fix-its for tag mismatches
11046 // since they usually mess up the template instead of fixing the problem.
11047 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
11048 << getRedeclDiagFromTagKind(NewTag) << isTemplate << &Name
11049 << getRedeclDiagFromTagKind(OldTag);
11053 if (isDefinition) {
11054 // On definitions, check previous tags and issue a fix-it for each
11055 // one that doesn't match the current tag.
11056 if (Previous->getDefinition()) {
11057 // Don't suggest fix-its for redefinitions.
11061 bool previousMismatch = false;
11062 for (auto I : Previous->redecls()) {
11063 if (I->getTagKind() != NewTag) {
11064 if (!previousMismatch) {
11065 previousMismatch = true;
11066 Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch)
11067 << getRedeclDiagFromTagKind(NewTag) << isTemplate << &Name
11068 << getRedeclDiagFromTagKind(I->getTagKind());
11070 Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion)
11071 << getRedeclDiagFromTagKind(NewTag)
11072 << FixItHint::CreateReplacement(I->getInnerLocStart(),
11073 TypeWithKeyword::getTagTypeKindName(NewTag));
11079 // Check for a previous definition. If current tag and definition
11080 // are same type, do nothing. If no definition, but disagree with
11081 // with previous tag type, give a warning, but no fix-it.
11082 const TagDecl *Redecl = Previous->getDefinition() ?
11083 Previous->getDefinition() : Previous;
11084 if (Redecl->getTagKind() == NewTag) {
11088 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)
11089 << getRedeclDiagFromTagKind(NewTag) << isTemplate << &Name
11090 << getRedeclDiagFromTagKind(OldTag);
11091 Diag(Redecl->getLocation(), diag::note_previous_use);
11093 // If there is a previous definition, suggest a fix-it.
11094 if (Previous->getDefinition()) {
11095 Diag(NewTagLoc, diag::note_struct_class_suggestion)
11096 << getRedeclDiagFromTagKind(Redecl->getTagKind())
11097 << FixItHint::CreateReplacement(SourceRange(NewTagLoc),
11098 TypeWithKeyword::getTagTypeKindName(Redecl->getTagKind()));
11106 /// Add a minimal nested name specifier fixit hint to allow lookup of a tag name
11107 /// from an outer enclosing namespace or file scope inside a friend declaration.
11108 /// This should provide the commented out code in the following snippet:
11112 /// struct Y { friend struct /*N::*/ X; };
11115 static FixItHint createFriendTagNNSFixIt(Sema &SemaRef, NamedDecl *ND, Scope *S,
11116 SourceLocation NameLoc) {
11117 // While the decl is in a namespace, do repeated lookup of that name and see
11118 // if we get the same namespace back. If we do not, continue until
11119 // translation unit scope, at which point we have a fully qualified NNS.
11120 SmallVector<IdentifierInfo *, 4> Namespaces;
11121 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
11122 for (; !DC->isTranslationUnit(); DC = DC->getParent()) {
11123 // This tag should be declared in a namespace, which can only be enclosed by
11124 // other namespaces. Bail if there's an anonymous namespace in the chain.
11125 NamespaceDecl *Namespace = dyn_cast<NamespaceDecl>(DC);
11126 if (!Namespace || Namespace->isAnonymousNamespace())
11127 return FixItHint();
11128 IdentifierInfo *II = Namespace->getIdentifier();
11129 Namespaces.push_back(II);
11130 NamedDecl *Lookup = SemaRef.LookupSingleName(
11131 S, II, NameLoc, Sema::LookupNestedNameSpecifierName);
11132 if (Lookup == Namespace)
11136 // Once we have all the namespaces, reverse them to go outermost first, and
11138 SmallString<64> Insertion;
11139 llvm::raw_svector_ostream OS(Insertion);
11140 if (DC->isTranslationUnit())
11142 std::reverse(Namespaces.begin(), Namespaces.end());
11143 for (auto *II : Namespaces)
11144 OS << II->getName() << "::";
11146 return FixItHint::CreateInsertion(NameLoc, Insertion);
11149 /// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the
11150 /// former case, Name will be non-null. In the later case, Name will be null.
11151 /// TagSpec indicates what kind of tag this is. TUK indicates whether this is a
11152 /// reference/declaration/definition of a tag.
11154 /// IsTypeSpecifier is true if this is a type-specifier (or
11155 /// trailing-type-specifier) other than one in an alias-declaration.
11156 Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
11157 SourceLocation KWLoc, CXXScopeSpec &SS,
11158 IdentifierInfo *Name, SourceLocation NameLoc,
11159 AttributeList *Attr, AccessSpecifier AS,
11160 SourceLocation ModulePrivateLoc,
11161 MultiTemplateParamsArg TemplateParameterLists,
11162 bool &OwnedDecl, bool &IsDependent,
11163 SourceLocation ScopedEnumKWLoc,
11164 bool ScopedEnumUsesClassTag,
11165 TypeResult UnderlyingType,
11166 bool IsTypeSpecifier) {
11167 // If this is not a definition, it must have a name.
11168 IdentifierInfo *OrigName = Name;
11169 assert((Name != nullptr || TUK == TUK_Definition) &&
11170 "Nameless record must be a definition!");
11171 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference);
11174 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
11175 bool ScopedEnum = ScopedEnumKWLoc.isValid();
11177 // FIXME: Check explicit specializations more carefully.
11178 bool isExplicitSpecialization = false;
11179 bool Invalid = false;
11181 // We only need to do this matching if we have template parameters
11182 // or a scope specifier, which also conveniently avoids this work
11183 // for non-C++ cases.
11184 if (TemplateParameterLists.size() > 0 ||
11185 (SS.isNotEmpty() && TUK != TUK_Reference)) {
11186 if (TemplateParameterList *TemplateParams =
11187 MatchTemplateParametersToScopeSpecifier(
11188 KWLoc, NameLoc, SS, nullptr, TemplateParameterLists,
11189 TUK == TUK_Friend, isExplicitSpecialization, Invalid)) {
11190 if (Kind == TTK_Enum) {
11191 Diag(KWLoc, diag::err_enum_template);
11195 if (TemplateParams->size() > 0) {
11196 // This is a declaration or definition of a class template (which may
11197 // be a member of another template).
11203 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc,
11204 SS, Name, NameLoc, Attr,
11205 TemplateParams, AS,
11207 /*FriendLoc*/SourceLocation(),
11208 TemplateParameterLists.size()-1,
11209 TemplateParameterLists.data());
11210 return Result.get();
11212 // The "template<>" header is extraneous.
11213 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
11214 << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
11215 isExplicitSpecialization = true;
11220 // Figure out the underlying type if this a enum declaration. We need to do
11221 // this early, because it's needed to detect if this is an incompatible
11223 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying;
11225 if (Kind == TTK_Enum) {
11226 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum))
11227 // No underlying type explicitly specified, or we failed to parse the
11228 // type, default to int.
11229 EnumUnderlying = Context.IntTy.getTypePtr();
11230 else if (UnderlyingType.get()) {
11231 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
11232 // integral type; any cv-qualification is ignored.
11233 TypeSourceInfo *TI = nullptr;
11234 GetTypeFromParser(UnderlyingType.get(), &TI);
11235 EnumUnderlying = TI;
11237 if (CheckEnumUnderlyingType(TI))
11238 // Recover by falling back to int.
11239 EnumUnderlying = Context.IntTy.getTypePtr();
11241 if (DiagnoseUnexpandedParameterPack(TI->getTypeLoc().getBeginLoc(), TI,
11242 UPPC_FixedUnderlyingType))
11243 EnumUnderlying = Context.IntTy.getTypePtr();
11245 } else if (getLangOpts().MSVCCompat)
11246 // Microsoft enums are always of int type.
11247 EnumUnderlying = Context.IntTy.getTypePtr();
11250 DeclContext *SearchDC = CurContext;
11251 DeclContext *DC = CurContext;
11252 bool isStdBadAlloc = false;
11254 RedeclarationKind Redecl = ForRedeclaration;
11255 if (TUK == TUK_Friend || TUK == TUK_Reference)
11256 Redecl = NotForRedeclaration;
11258 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl);
11259 if (Name && SS.isNotEmpty()) {
11260 // We have a nested-name tag ('struct foo::bar').
11262 // Check for invalid 'foo::'.
11263 if (SS.isInvalid()) {
11265 goto CreateNewDecl;
11268 // If this is a friend or a reference to a class in a dependent
11269 // context, don't try to make a decl for it.
11270 if (TUK == TUK_Friend || TUK == TUK_Reference) {
11271 DC = computeDeclContext(SS, false);
11273 IsDependent = true;
11277 DC = computeDeclContext(SS, true);
11279 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec)
11285 if (RequireCompleteDeclContext(SS, DC))
11289 // Look-up name inside 'foo::'.
11290 LookupQualifiedName(Previous, DC);
11292 if (Previous.isAmbiguous())
11295 if (Previous.empty()) {
11296 // Name lookup did not find anything. However, if the
11297 // nested-name-specifier refers to the current instantiation,
11298 // and that current instantiation has any dependent base
11299 // classes, we might find something at instantiation time: treat
11300 // this as a dependent elaborated-type-specifier.
11301 // But this only makes any sense for reference-like lookups.
11302 if (Previous.wasNotFoundInCurrentInstantiation() &&
11303 (TUK == TUK_Reference || TUK == TUK_Friend)) {
11304 IsDependent = true;
11308 // A tag 'foo::bar' must already exist.
11309 Diag(NameLoc, diag::err_not_tag_in_scope)
11310 << Kind << Name << DC << SS.getRange();
11313 goto CreateNewDecl;
11316 // If this is a named struct, check to see if there was a previous forward
11317 // declaration or definition.
11318 // FIXME: We're looking into outer scopes here, even when we
11319 // shouldn't be. Doing so can result in ambiguities that we
11320 // shouldn't be diagnosing.
11321 LookupName(Previous, S);
11323 // When declaring or defining a tag, ignore ambiguities introduced
11324 // by types using'ed into this scope.
11325 if (Previous.isAmbiguous() &&
11326 (TUK == TUK_Definition || TUK == TUK_Declaration)) {
11327 LookupResult::Filter F = Previous.makeFilter();
11328 while (F.hasNext()) {
11329 NamedDecl *ND = F.next();
11330 if (ND->getDeclContext()->getRedeclContext() != SearchDC)
11336 // C++11 [namespace.memdef]p3:
11337 // If the name in a friend declaration is neither qualified nor
11338 // a template-id and the declaration is a function or an
11339 // elaborated-type-specifier, the lookup to determine whether
11340 // the entity has been previously declared shall not consider
11341 // any scopes outside the innermost enclosing namespace.
11343 // MSVC doesn't implement the above rule for types, so a friend tag
11344 // declaration may be a redeclaration of a type declared in an enclosing
11345 // scope. They do implement this rule for friend functions.
11347 // Does it matter that this should be by scope instead of by
11348 // semantic context?
11349 if (!Previous.empty() && TUK == TUK_Friend) {
11350 DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext();
11351 LookupResult::Filter F = Previous.makeFilter();
11352 bool FriendSawTagOutsideEnclosingNamespace = false;
11353 while (F.hasNext()) {
11354 NamedDecl *ND = F.next();
11355 DeclContext *DC = ND->getDeclContext()->getRedeclContext();
11356 if (DC->isFileContext() &&
11357 !EnclosingNS->Encloses(ND->getDeclContext())) {
11358 if (getLangOpts().MSVCCompat)
11359 FriendSawTagOutsideEnclosingNamespace = true;
11366 // Diagnose this MSVC extension in the easy case where lookup would have
11367 // unambiguously found something outside the enclosing namespace.
11368 if (Previous.isSingleResult() && FriendSawTagOutsideEnclosingNamespace) {
11369 NamedDecl *ND = Previous.getFoundDecl();
11370 Diag(NameLoc, diag::ext_friend_tag_redecl_outside_namespace)
11371 << createFriendTagNNSFixIt(*this, ND, S, NameLoc);
11375 // Note: there used to be some attempt at recovery here.
11376 if (Previous.isAmbiguous())
11379 if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) {
11380 // FIXME: This makes sure that we ignore the contexts associated
11381 // with C structs, unions, and enums when looking for a matching
11382 // tag declaration or definition. See the similar lookup tweak
11383 // in Sema::LookupName; is there a better way to deal with this?
11384 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
11385 SearchDC = SearchDC->getParent();
11389 if (Previous.isSingleResult() &&
11390 Previous.getFoundDecl()->isTemplateParameter()) {
11391 // Maybe we will complain about the shadowed template parameter.
11392 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
11393 // Just pretend that we didn't see the previous declaration.
11397 if (getLangOpts().CPlusPlus && Name && DC && StdNamespace &&
11398 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) {
11399 // This is a declaration of or a reference to "std::bad_alloc".
11400 isStdBadAlloc = true;
11402 if (Previous.empty() && StdBadAlloc) {
11403 // std::bad_alloc has been implicitly declared (but made invisible to
11404 // name lookup). Fill in this implicit declaration as the previous
11405 // declaration, so that the declarations get chained appropriately.
11406 Previous.addDecl(getStdBadAlloc());
11410 // If we didn't find a previous declaration, and this is a reference
11411 // (or friend reference), move to the correct scope. In C++, we
11412 // also need to do a redeclaration lookup there, just in case
11413 // there's a shadow friend decl.
11414 if (Name && Previous.empty() &&
11415 (TUK == TUK_Reference || TUK == TUK_Friend)) {
11416 if (Invalid) goto CreateNewDecl;
11417 assert(SS.isEmpty());
11419 if (TUK == TUK_Reference) {
11420 // C++ [basic.scope.pdecl]p5:
11421 // -- for an elaborated-type-specifier of the form
11423 // class-key identifier
11425 // if the elaborated-type-specifier is used in the
11426 // decl-specifier-seq or parameter-declaration-clause of a
11427 // function defined in namespace scope, the identifier is
11428 // declared as a class-name in the namespace that contains
11429 // the declaration; otherwise, except as a friend
11430 // declaration, the identifier is declared in the smallest
11431 // non-class, non-function-prototype scope that contains the
11434 // C99 6.7.2.3p8 has a similar (but not identical!) provision for
11435 // C structs and unions.
11437 // It is an error in C++ to declare (rather than define) an enum
11438 // type, including via an elaborated type specifier. We'll
11439 // diagnose that later; for now, declare the enum in the same
11440 // scope as we would have picked for any other tag type.
11442 // GNU C also supports this behavior as part of its incomplete
11443 // enum types extension, while GNU C++ does not.
11445 // Find the context where we'll be declaring the tag.
11446 // FIXME: We would like to maintain the current DeclContext as the
11447 // lexical context,
11448 while (!SearchDC->isFileContext() && !SearchDC->isFunctionOrMethod())
11449 SearchDC = SearchDC->getParent();
11451 // Find the scope where we'll be declaring the tag.
11452 while (S->isClassScope() ||
11453 (getLangOpts().CPlusPlus &&
11454 S->isFunctionPrototypeScope()) ||
11455 ((S->getFlags() & Scope::DeclScope) == 0) ||
11456 (S->getEntity() && S->getEntity()->isTransparentContext()))
11457 S = S->getParent();
11459 assert(TUK == TUK_Friend);
11460 // C++ [namespace.memdef]p3:
11461 // If a friend declaration in a non-local class first declares a
11462 // class or function, the friend class or function is a member of
11463 // the innermost enclosing namespace.
11464 SearchDC = SearchDC->getEnclosingNamespaceContext();
11467 // In C++, we need to do a redeclaration lookup to properly
11468 // diagnose some problems.
11469 if (getLangOpts().CPlusPlus) {
11470 Previous.setRedeclarationKind(ForRedeclaration);
11471 LookupQualifiedName(Previous, SearchDC);
11475 if (!Previous.empty()) {
11476 NamedDecl *PrevDecl = Previous.getFoundDecl();
11477 NamedDecl *DirectPrevDecl =
11478 getLangOpts().MSVCCompat ? *Previous.begin() : PrevDecl;
11480 // It's okay to have a tag decl in the same scope as a typedef
11481 // which hides a tag decl in the same scope. Finding this
11482 // insanity with a redeclaration lookup can only actually happen
11485 // This is also okay for elaborated-type-specifiers, which is
11486 // technically forbidden by the current standard but which is
11487 // okay according to the likely resolution of an open issue;
11488 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
11489 if (getLangOpts().CPlusPlus) {
11490 if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
11491 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
11492 TagDecl *Tag = TT->getDecl();
11493 if (Tag->getDeclName() == Name &&
11494 Tag->getDeclContext()->getRedeclContext()
11495 ->Equals(TD->getDeclContext()->getRedeclContext())) {
11498 Previous.addDecl(Tag);
11499 Previous.resolveKind();
11505 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
11506 // If this is a use of a previous tag, or if the tag is already declared
11507 // in the same scope (so that the definition/declaration completes or
11508 // rementions the tag), reuse the decl.
11509 if (TUK == TUK_Reference || TUK == TUK_Friend ||
11510 isDeclInScope(DirectPrevDecl, SearchDC, S,
11511 SS.isNotEmpty() || isExplicitSpecialization)) {
11512 // Make sure that this wasn't declared as an enum and now used as a
11513 // struct or something similar.
11514 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind,
11515 TUK == TUK_Definition, KWLoc,
11517 bool SafeToContinue
11518 = (PrevTagDecl->getTagKind() != TTK_Enum &&
11520 if (SafeToContinue)
11521 Diag(KWLoc, diag::err_use_with_wrong_tag)
11523 << FixItHint::CreateReplacement(SourceRange(KWLoc),
11524 PrevTagDecl->getKindName());
11526 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
11527 Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
11529 if (SafeToContinue)
11530 Kind = PrevTagDecl->getTagKind();
11532 // Recover by making this an anonymous redefinition.
11539 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
11540 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);
11542 // If this is an elaborated-type-specifier for a scoped enumeration,
11543 // the 'class' keyword is not necessary and not permitted.
11544 if (TUK == TUK_Reference || TUK == TUK_Friend) {
11546 Diag(ScopedEnumKWLoc, diag::err_enum_class_reference)
11547 << PrevEnum->isScoped()
11548 << FixItHint::CreateRemoval(ScopedEnumKWLoc);
11549 return PrevTagDecl;
11552 QualType EnumUnderlyingTy;
11553 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
11554 EnumUnderlyingTy = TI->getType().getUnqualifiedType();
11555 else if (const Type *T = EnumUnderlying.dyn_cast<const Type*>())
11556 EnumUnderlyingTy = QualType(T, 0);
11558 // All conflicts with previous declarations are recovered by
11559 // returning the previous declaration, unless this is a definition,
11560 // in which case we want the caller to bail out.
11561 if (CheckEnumRedeclaration(NameLoc.isValid() ? NameLoc : KWLoc,
11562 ScopedEnum, EnumUnderlyingTy, PrevEnum))
11563 return TUK == TUK_Declaration ? PrevTagDecl : nullptr;
11566 // C++11 [class.mem]p1:
11567 // A member shall not be declared twice in the member-specification,
11568 // except that a nested class or member class template can be declared
11569 // and then later defined.
11570 if (TUK == TUK_Declaration && PrevDecl->isCXXClassMember() &&
11571 S->isDeclScope(PrevDecl)) {
11572 Diag(NameLoc, diag::ext_member_redeclared);
11573 Diag(PrevTagDecl->getLocation(), diag::note_previous_declaration);
11577 // If this is a use, just return the declaration we found, unless
11578 // we have attributes.
11580 // FIXME: In the future, return a variant or some other clue
11581 // for the consumer of this Decl to know it doesn't own it.
11582 // For our current ASTs this shouldn't be a problem, but will
11583 // need to be changed with DeclGroups.
11585 ((TUK == TUK_Reference &&
11586 (!PrevTagDecl->getFriendObjectKind() || getLangOpts().MicrosoftExt))
11587 || TUK == TUK_Friend))
11588 return PrevTagDecl;
11590 // Diagnose attempts to redefine a tag.
11591 if (TUK == TUK_Definition) {
11592 if (TagDecl *Def = PrevTagDecl->getDefinition()) {
11593 // If we're defining a specialization and the previous definition
11594 // is from an implicit instantiation, don't emit an error
11595 // here; we'll catch this in the general case below.
11596 bool IsExplicitSpecializationAfterInstantiation = false;
11597 if (isExplicitSpecialization) {
11598 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Def))
11599 IsExplicitSpecializationAfterInstantiation =
11600 RD->getTemplateSpecializationKind() !=
11601 TSK_ExplicitSpecialization;
11602 else if (EnumDecl *ED = dyn_cast<EnumDecl>(Def))
11603 IsExplicitSpecializationAfterInstantiation =
11604 ED->getTemplateSpecializationKind() !=
11605 TSK_ExplicitSpecialization;
11608 if (!IsExplicitSpecializationAfterInstantiation) {
11609 // A redeclaration in function prototype scope in C isn't
11610 // visible elsewhere, so merely issue a warning.
11611 if (!getLangOpts().CPlusPlus && S->containedInPrototypeScope())
11612 Diag(NameLoc, diag::warn_redefinition_in_param_list) << Name;
11614 Diag(NameLoc, diag::err_redefinition) << Name;
11615 Diag(Def->getLocation(), diag::note_previous_definition);
11616 // If this is a redefinition, recover by making this
11617 // struct be anonymous, which will make any later
11618 // references get the previous definition.
11624 // If the type is currently being defined, complain
11625 // about a nested redefinition.
11626 auto *TD = Context.getTagDeclType(PrevTagDecl)->getAsTagDecl();
11627 if (TD->isBeingDefined()) {
11628 Diag(NameLoc, diag::err_nested_redefinition) << Name;
11629 Diag(PrevTagDecl->getLocation(),
11630 diag::note_previous_definition);
11637 // Okay, this is definition of a previously declared or referenced
11638 // tag. We're going to create a new Decl for it.
11641 // Okay, we're going to make a redeclaration. If this is some kind
11642 // of reference, make sure we build the redeclaration in the same DC
11643 // as the original, and ignore the current access specifier.
11644 if (TUK == TUK_Friend || TUK == TUK_Reference) {
11645 SearchDC = PrevTagDecl->getDeclContext();
11649 // If we get here we have (another) forward declaration or we
11650 // have a definition. Just create a new decl.
11653 // If we get here, this is a definition of a new tag type in a nested
11654 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a
11655 // new decl/type. We set PrevDecl to NULL so that the entities
11656 // have distinct types.
11659 // If we get here, we're going to create a new Decl. If PrevDecl
11660 // is non-NULL, it's a definition of the tag declared by
11661 // PrevDecl. If it's NULL, we have a new definition.
11664 // Otherwise, PrevDecl is not a tag, but was found with tag
11665 // lookup. This is only actually possible in C++, where a few
11666 // things like templates still live in the tag namespace.
11668 // Use a better diagnostic if an elaborated-type-specifier
11669 // found the wrong kind of type on the first
11670 // (non-redeclaration) lookup.
11671 if ((TUK == TUK_Reference || TUK == TUK_Friend) &&
11672 !Previous.isForRedeclaration()) {
11674 if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
11675 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
11676 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
11677 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind;
11678 Diag(PrevDecl->getLocation(), diag::note_declared_at);
11681 // Otherwise, only diagnose if the declaration is in scope.
11682 } else if (!isDeclInScope(PrevDecl, SearchDC, S,
11683 SS.isNotEmpty() || isExplicitSpecialization)) {
11686 // Diagnose implicit declarations introduced by elaborated types.
11687 } else if (TUK == TUK_Reference || TUK == TUK_Friend) {
11689 if (isa<TypedefDecl>(PrevDecl)) Kind = 1;
11690 else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2;
11691 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3;
11692 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind;
11693 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
11696 // Otherwise it's a declaration. Call out a particularly common
11698 } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
11700 if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
11701 Diag(NameLoc, diag::err_tag_definition_of_typedef)
11702 << Name << Kind << TND->getUnderlyingType();
11703 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl;
11706 // Otherwise, diagnose.
11708 // The tag name clashes with something else in the target scope,
11709 // issue an error and recover by making this tag be anonymous.
11710 Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
11711 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
11716 // The existing declaration isn't relevant to us; we're in a
11717 // new scope, so clear out the previous declaration.
11724 TagDecl *PrevDecl = nullptr;
11725 if (Previous.isSingleResult())
11726 PrevDecl = cast<TagDecl>(Previous.getFoundDecl());
11728 // If there is an identifier, use the location of the identifier as the
11729 // location of the decl, otherwise use the location of the struct/union
11731 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc;
11733 // Otherwise, create a new declaration. If there is a previous
11734 // declaration of the same entity, the two will be linked via
11738 bool IsForwardReference = false;
11739 if (Kind == TTK_Enum) {
11740 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
11741 // enum X { A, B, C } D; D should chain to X.
11742 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name,
11743 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum,
11744 ScopedEnumUsesClassTag, !EnumUnderlying.isNull());
11745 // If this is an undefined enum, warn.
11746 if (TUK != TUK_Definition && !Invalid) {
11748 if ((getLangOpts().CPlusPlus11 || getLangOpts().ObjC2) &&
11749 cast<EnumDecl>(New)->isFixed()) {
11750 // C++0x: 7.2p2: opaque-enum-declaration.
11751 // Conflicts are diagnosed above. Do nothing.
11753 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) {
11754 Diag(Loc, diag::ext_forward_ref_enum_def)
11756 Diag(Def->getLocation(), diag::note_previous_definition);
11758 unsigned DiagID = diag::ext_forward_ref_enum;
11759 if (getLangOpts().MSVCCompat)
11760 DiagID = diag::ext_ms_forward_ref_enum;
11761 else if (getLangOpts().CPlusPlus)
11762 DiagID = diag::err_forward_ref_enum;
11765 // If this is a forward-declared reference to an enumeration, make a
11766 // note of it; we won't actually be introducing the declaration into
11767 // the declaration context.
11768 if (TUK == TUK_Reference)
11769 IsForwardReference = true;
11773 if (EnumUnderlying) {
11774 EnumDecl *ED = cast<EnumDecl>(New);
11775 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
11776 ED->setIntegerTypeSourceInfo(TI);
11778 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
11779 ED->setPromotionType(ED->getIntegerType());
11783 // struct/union/class
11785 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.:
11786 // struct X { int A; } D; D should chain to X.
11787 if (getLangOpts().CPlusPlus) {
11788 // FIXME: Look for a way to use RecordDecl for simple structs.
11789 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
11790 cast_or_null<CXXRecordDecl>(PrevDecl));
11792 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit()))
11793 StdBadAlloc = cast<CXXRecordDecl>(New);
11795 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
11796 cast_or_null<RecordDecl>(PrevDecl));
11799 // C++11 [dcl.type]p3:
11800 // A type-specifier-seq shall not define a class or enumeration [...].
11801 if (getLangOpts().CPlusPlus && IsTypeSpecifier && TUK == TUK_Definition) {
11802 Diag(New->getLocation(), diag::err_type_defined_in_type_specifier)
11803 << Context.getTagDeclType(New);
11807 // Maybe add qualifier info.
11808 if (SS.isNotEmpty()) {
11810 // If this is either a declaration or a definition, check the
11811 // nested-name-specifier against the current context. We don't do this
11812 // for explicit specializations, because they have similar checking
11813 // (with more specific diagnostics) in the call to
11814 // CheckMemberSpecialization, below.
11815 if (!isExplicitSpecialization &&
11816 (TUK == TUK_Definition || TUK == TUK_Declaration) &&
11817 diagnoseQualifiedDeclaration(SS, DC, OrigName, Loc))
11820 New->setQualifierInfo(SS.getWithLocInContext(Context));
11821 if (TemplateParameterLists.size() > 0) {
11822 New->setTemplateParameterListsInfo(Context,
11823 TemplateParameterLists.size(),
11824 TemplateParameterLists.data());
11831 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) {
11832 // Add alignment attributes if necessary; these attributes are checked when
11833 // the ASTContext lays out the structure.
11835 // It is important for implementing the correct semantics that this
11836 // happen here (in act on tag decl). The #pragma pack stack is
11837 // maintained as a result of parser callbacks which can occur at
11838 // many points during the parsing of a struct declaration (because
11839 // the #pragma tokens are effectively skipped over during the
11840 // parsing of the struct).
11841 if (TUK == TUK_Definition) {
11842 AddAlignmentAttributesForRecord(RD);
11843 AddMsStructLayoutForRecord(RD);
11847 if (ModulePrivateLoc.isValid()) {
11848 if (isExplicitSpecialization)
11849 Diag(New->getLocation(), diag::err_module_private_specialization)
11851 << FixItHint::CreateRemoval(ModulePrivateLoc);
11852 // __module_private__ does not apply to local classes. However, we only
11853 // diagnose this as an error when the declaration specifiers are
11854 // freestanding. Here, we just ignore the __module_private__.
11855 else if (!SearchDC->isFunctionOrMethod())
11856 New->setModulePrivate();
11859 // If this is a specialization of a member class (of a class template),
11860 // check the specialization.
11861 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous))
11864 // If we're declaring or defining a tag in function prototype scope in C,
11865 // note that this type can only be used within the function and add it to
11866 // the list of decls to inject into the function definition scope.
11867 if ((Name || Kind == TTK_Enum) &&
11868 getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
11869 if (getLangOpts().CPlusPlus) {
11870 // C++ [dcl.fct]p6:
11871 // Types shall not be defined in return or parameter types.
11872 if (TUK == TUK_Definition && !IsTypeSpecifier) {
11873 Diag(Loc, diag::err_type_defined_in_param_type)
11878 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
11880 DeclsInPrototypeScope.push_back(New);
11884 New->setInvalidDecl();
11887 ProcessDeclAttributeList(S, New, Attr);
11889 // Set the lexical context. If the tag has a C++ scope specifier, the
11890 // lexical context will be different from the semantic context.
11891 New->setLexicalDeclContext(CurContext);
11893 // Mark this as a friend decl if applicable.
11894 // In Microsoft mode, a friend declaration also acts as a forward
11895 // declaration so we always pass true to setObjectOfFriendDecl to make
11896 // the tag name visible.
11897 if (TUK == TUK_Friend)
11898 New->setObjectOfFriendDecl(getLangOpts().MSVCCompat);
11900 // Set the access specifier.
11901 if (!Invalid && SearchDC->isRecord())
11902 SetMemberAccessSpecifier(New, PrevDecl, AS);
11904 if (TUK == TUK_Definition)
11905 New->startDefinition();
11907 // If this has an identifier, add it to the scope stack.
11908 if (TUK == TUK_Friend) {
11909 // We might be replacing an existing declaration in the lookup tables;
11910 // if so, borrow its access specifier.
11912 New->setAccess(PrevDecl->getAccess());
11914 DeclContext *DC = New->getDeclContext()->getRedeclContext();
11915 DC->makeDeclVisibleInContext(New);
11916 if (Name) // can be null along some error paths
11917 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
11918 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false);
11920 S = getNonFieldDeclScope(S);
11921 PushOnScopeChains(New, S, !IsForwardReference);
11922 if (IsForwardReference)
11923 SearchDC->makeDeclVisibleInContext(New);
11926 CurContext->addDecl(New);
11929 // If this is the C FILE type, notify the AST context.
11930 if (IdentifierInfo *II = New->getIdentifier())
11931 if (!New->isInvalidDecl() &&
11932 New->getDeclContext()->getRedeclContext()->isTranslationUnit() &&
11934 Context.setFILEDecl(New);
11937 mergeDeclAttributes(New, PrevDecl);
11939 // If there's a #pragma GCC visibility in scope, set the visibility of this
11941 AddPushedVisibilityAttribute(New);
11944 // In C++, don't return an invalid declaration. We can't recover well from
11945 // the cases where we make the type anonymous.
11946 return (Invalid && getLangOpts().CPlusPlus) ? nullptr : New;
11949 void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) {
11950 AdjustDeclIfTemplate(TagD);
11951 TagDecl *Tag = cast<TagDecl>(TagD);
11953 // Enter the tag context.
11954 PushDeclContext(S, Tag);
11956 ActOnDocumentableDecl(TagD);
11958 // If there's a #pragma GCC visibility in scope, set the visibility of this
11960 AddPushedVisibilityAttribute(Tag);
11963 Decl *Sema::ActOnObjCContainerStartDefinition(Decl *IDecl) {
11964 assert(isa<ObjCContainerDecl>(IDecl) &&
11965 "ActOnObjCContainerStartDefinition - Not ObjCContainerDecl");
11966 DeclContext *OCD = cast<DeclContext>(IDecl);
11967 assert(getContainingDC(OCD) == CurContext &&
11968 "The next DeclContext should be lexically contained in the current one.");
11973 void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD,
11974 SourceLocation FinalLoc,
11975 bool IsFinalSpelledSealed,
11976 SourceLocation LBraceLoc) {
11977 AdjustDeclIfTemplate(TagD);
11978 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD);
11980 FieldCollector->StartClass();
11982 if (!Record->getIdentifier())
11985 if (FinalLoc.isValid())
11986 Record->addAttr(new (Context)
11987 FinalAttr(FinalLoc, Context, IsFinalSpelledSealed));
11990 // [...] The class-name is also inserted into the scope of the
11991 // class itself; this is known as the injected-class-name. For
11992 // purposes of access checking, the injected-class-name is treated
11993 // as if it were a public member name.
11994 CXXRecordDecl *InjectedClassName
11995 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext,
11996 Record->getLocStart(), Record->getLocation(),
11997 Record->getIdentifier(),
11998 /*PrevDecl=*/nullptr,
11999 /*DelayTypeCreation=*/true);
12000 Context.getTypeDeclType(InjectedClassName, Record);
12001 InjectedClassName->setImplicit();
12002 InjectedClassName->setAccess(AS_public);
12003 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate())
12004 InjectedClassName->setDescribedClassTemplate(Template);
12005 PushOnScopeChains(InjectedClassName, S);
12006 assert(InjectedClassName->isInjectedClassName() &&
12007 "Broken injected-class-name");
12010 void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD,
12011 SourceLocation RBraceLoc) {
12012 AdjustDeclIfTemplate(TagD);
12013 TagDecl *Tag = cast<TagDecl>(TagD);
12014 Tag->setRBraceLoc(RBraceLoc);
12016 // Make sure we "complete" the definition even it is invalid.
12017 if (Tag->isBeingDefined()) {
12018 assert(Tag->isInvalidDecl() && "We should already have completed it");
12019 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
12020 RD->completeDefinition();
12023 if (isa<CXXRecordDecl>(Tag))
12024 FieldCollector->FinishClass();
12026 // Exit this scope of this tag's definition.
12029 if (getCurLexicalContext()->isObjCContainer() &&
12030 Tag->getDeclContext()->isFileContext())
12031 Tag->setTopLevelDeclInObjCContainer();
12033 // Notify the consumer that we've defined a tag.
12034 if (!Tag->isInvalidDecl())
12035 Consumer.HandleTagDeclDefinition(Tag);
12038 void Sema::ActOnObjCContainerFinishDefinition() {
12039 // Exit this scope of this interface definition.
12043 void Sema::ActOnObjCTemporaryExitContainerContext(DeclContext *DC) {
12044 assert(DC == CurContext && "Mismatch of container contexts");
12045 OriginalLexicalContext = DC;
12046 ActOnObjCContainerFinishDefinition();
12049 void Sema::ActOnObjCReenterContainerContext(DeclContext *DC) {
12050 ActOnObjCContainerStartDefinition(cast<Decl>(DC));
12051 OriginalLexicalContext = nullptr;
12054 void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) {
12055 AdjustDeclIfTemplate(TagD);
12056 TagDecl *Tag = cast<TagDecl>(TagD);
12057 Tag->setInvalidDecl();
12059 // Make sure we "complete" the definition even it is invalid.
12060 if (Tag->isBeingDefined()) {
12061 if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag))
12062 RD->completeDefinition();
12065 // We're undoing ActOnTagStartDefinition here, not
12066 // ActOnStartCXXMemberDeclarations, so we don't have to mess with
12067 // the FieldCollector.
12072 // Note that FieldName may be null for anonymous bitfields.
12073 ExprResult Sema::VerifyBitField(SourceLocation FieldLoc,
12074 IdentifierInfo *FieldName,
12075 QualType FieldTy, bool IsMsStruct,
12076 Expr *BitWidth, bool *ZeroWidth) {
12077 // Default to true; that shouldn't confuse checks for emptiness
12081 // C99 6.7.2.1p4 - verify the field type.
12082 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
12083 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) {
12084 // Handle incomplete types with specific error.
12085 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete))
12086 return ExprError();
12088 return Diag(FieldLoc, diag::err_not_integral_type_bitfield)
12089 << FieldName << FieldTy << BitWidth->getSourceRange();
12090 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield)
12091 << FieldTy << BitWidth->getSourceRange();
12092 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth),
12093 UPPC_BitFieldWidth))
12094 return ExprError();
12096 // If the bit-width is type- or value-dependent, don't try to check
12098 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent())
12101 llvm::APSInt Value;
12102 ExprResult ICE = VerifyIntegerConstantExpression(BitWidth, &Value);
12103 if (ICE.isInvalid())
12105 BitWidth = ICE.get();
12107 if (Value != 0 && ZeroWidth)
12108 *ZeroWidth = false;
12110 // Zero-width bitfield is ok for anonymous field.
12111 if (Value == 0 && FieldName)
12112 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName;
12114 if (Value.isSigned() && Value.isNegative()) {
12116 return Diag(FieldLoc, diag::err_bitfield_has_negative_width)
12117 << FieldName << Value.toString(10);
12118 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width)
12119 << Value.toString(10);
12122 if (!FieldTy->isDependentType()) {
12123 uint64_t TypeSize = Context.getTypeSize(FieldTy);
12124 if (Value.getZExtValue() > TypeSize) {
12125 if (!getLangOpts().CPlusPlus || IsMsStruct ||
12126 Context.getTargetInfo().getCXXABI().isMicrosoft()) {
12128 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size)
12129 << FieldName << (unsigned)Value.getZExtValue()
12130 << (unsigned)TypeSize;
12132 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size)
12133 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize;
12137 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size)
12138 << FieldName << (unsigned)Value.getZExtValue()
12139 << (unsigned)TypeSize;
12141 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size)
12142 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize;
12149 /// ActOnField - Each field of a C struct/union is passed into this in order
12150 /// to create a FieldDecl object for it.
12151 Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
12152 Declarator &D, Expr *BitfieldWidth) {
12153 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD),
12154 DeclStart, D, static_cast<Expr*>(BitfieldWidth),
12155 /*InitStyle=*/ICIS_NoInit, AS_public);
12159 /// HandleField - Analyze a field of a C struct or a C++ data member.
12161 FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
12162 SourceLocation DeclStart,
12163 Declarator &D, Expr *BitWidth,
12164 InClassInitStyle InitStyle,
12165 AccessSpecifier AS) {
12166 IdentifierInfo *II = D.getIdentifier();
12167 SourceLocation Loc = DeclStart;
12168 if (II) Loc = D.getIdentifierLoc();
12170 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
12171 QualType T = TInfo->getType();
12172 if (getLangOpts().CPlusPlus) {
12173 CheckExtraCXXDefaultArguments(D);
12175 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
12176 UPPC_DataMemberType)) {
12177 D.setInvalidType();
12179 TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
12183 // TR 18037 does not allow fields to be declared with address spaces.
12184 if (T.getQualifiers().hasAddressSpace()) {
12185 Diag(Loc, diag::err_field_with_address_space);
12186 D.setInvalidType();
12189 // OpenCL 1.2 spec, s6.9 r:
12190 // The event type cannot be used to declare a structure or union field.
12191 if (LangOpts.OpenCL && T->isEventT()) {
12192 Diag(Loc, diag::err_event_t_struct_field);
12193 D.setInvalidType();
12196 DiagnoseFunctionSpecifiers(D.getDeclSpec());
12198 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
12199 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
12200 diag::err_invalid_thread)
12201 << DeclSpec::getSpecifierName(TSCS);
12203 // Check to see if this name was declared as a member previously
12204 NamedDecl *PrevDecl = nullptr;
12205 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
12206 LookupName(Previous, S);
12207 switch (Previous.getResultKind()) {
12208 case LookupResult::Found:
12209 case LookupResult::FoundUnresolvedValue:
12210 PrevDecl = Previous.getAsSingle<NamedDecl>();
12213 case LookupResult::FoundOverloaded:
12214 PrevDecl = Previous.getRepresentativeDecl();
12217 case LookupResult::NotFound:
12218 case LookupResult::NotFoundInCurrentInstantiation:
12219 case LookupResult::Ambiguous:
12222 Previous.suppressDiagnostics();
12224 if (PrevDecl && PrevDecl->isTemplateParameter()) {
12225 // Maybe we will complain about the shadowed template parameter.
12226 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
12227 // Just pretend that we didn't see the previous declaration.
12228 PrevDecl = nullptr;
12231 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
12232 PrevDecl = nullptr;
12235 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable);
12236 SourceLocation TSSL = D.getLocStart();
12238 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, InitStyle,
12239 TSSL, AS, PrevDecl, &D);
12241 if (NewFD->isInvalidDecl())
12242 Record->setInvalidDecl();
12244 if (D.getDeclSpec().isModulePrivateSpecified())
12245 NewFD->setModulePrivate();
12247 if (NewFD->isInvalidDecl() && PrevDecl) {
12248 // Don't introduce NewFD into scope; there's already something
12249 // with the same name in the same scope.
12251 PushOnScopeChains(NewFD, S);
12253 Record->addDecl(NewFD);
12258 /// \brief Build a new FieldDecl and check its well-formedness.
12260 /// This routine builds a new FieldDecl given the fields name, type,
12261 /// record, etc. \p PrevDecl should refer to any previous declaration
12262 /// with the same name and in the same scope as the field to be
12265 /// \returns a new FieldDecl.
12267 /// \todo The Declarator argument is a hack. It will be removed once
12268 FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T,
12269 TypeSourceInfo *TInfo,
12270 RecordDecl *Record, SourceLocation Loc,
12271 bool Mutable, Expr *BitWidth,
12272 InClassInitStyle InitStyle,
12273 SourceLocation TSSL,
12274 AccessSpecifier AS, NamedDecl *PrevDecl,
12276 IdentifierInfo *II = Name.getAsIdentifierInfo();
12277 bool InvalidDecl = false;
12278 if (D) InvalidDecl = D->isInvalidType();
12280 // If we receive a broken type, recover by assuming 'int' and
12281 // marking this declaration as invalid.
12283 InvalidDecl = true;
12287 QualType EltTy = Context.getBaseElementType(T);
12288 if (!EltTy->isDependentType()) {
12289 if (RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) {
12290 // Fields of incomplete type force their record to be invalid.
12291 Record->setInvalidDecl();
12292 InvalidDecl = true;
12295 EltTy->isIncompleteType(&Def);
12296 if (Def && Def->isInvalidDecl()) {
12297 Record->setInvalidDecl();
12298 InvalidDecl = true;
12303 // OpenCL v1.2 s6.9.c: bitfields are not supported.
12304 if (BitWidth && getLangOpts().OpenCL) {
12305 Diag(Loc, diag::err_opencl_bitfields);
12306 InvalidDecl = true;
12309 // C99 6.7.2.1p8: A member of a structure or union may have any type other
12310 // than a variably modified type.
12311 if (!InvalidDecl && T->isVariablyModifiedType()) {
12312 bool SizeIsNegative;
12313 llvm::APSInt Oversized;
12315 TypeSourceInfo *FixedTInfo =
12316 TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context,
12320 Diag(Loc, diag::warn_illegal_constant_array_size);
12321 TInfo = FixedTInfo;
12322 T = FixedTInfo->getType();
12324 if (SizeIsNegative)
12325 Diag(Loc, diag::err_typecheck_negative_array_size);
12326 else if (Oversized.getBoolValue())
12327 Diag(Loc, diag::err_array_too_large)
12328 << Oversized.toString(10);
12330 Diag(Loc, diag::err_typecheck_field_variable_size);
12331 InvalidDecl = true;
12335 // Fields can not have abstract class types
12336 if (!InvalidDecl && RequireNonAbstractType(Loc, T,
12337 diag::err_abstract_type_in_decl,
12338 AbstractFieldType))
12339 InvalidDecl = true;
12341 bool ZeroWidth = false;
12342 // If this is declared as a bit-field, check the bit-field.
12343 if (!InvalidDecl && BitWidth) {
12344 BitWidth = VerifyBitField(Loc, II, T, Record->isMsStruct(Context), BitWidth,
12347 InvalidDecl = true;
12348 BitWidth = nullptr;
12353 // Check that 'mutable' is consistent with the type of the declaration.
12354 if (!InvalidDecl && Mutable) {
12355 unsigned DiagID = 0;
12356 if (T->isReferenceType())
12357 DiagID = diag::err_mutable_reference;
12358 else if (T.isConstQualified())
12359 DiagID = diag::err_mutable_const;
12362 SourceLocation ErrLoc = Loc;
12363 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid())
12364 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc();
12365 Diag(ErrLoc, DiagID);
12367 InvalidDecl = true;
12371 // C++11 [class.union]p8 (DR1460):
12372 // At most one variant member of a union may have a
12373 // brace-or-equal-initializer.
12374 if (InitStyle != ICIS_NoInit)
12375 checkDuplicateDefaultInit(*this, cast<CXXRecordDecl>(Record), Loc);
12377 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo,
12378 BitWidth, Mutable, InitStyle);
12380 NewFD->setInvalidDecl();
12382 if (PrevDecl && !isa<TagDecl>(PrevDecl)) {
12383 Diag(Loc, diag::err_duplicate_member) << II;
12384 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
12385 NewFD->setInvalidDecl();
12388 if (!InvalidDecl && getLangOpts().CPlusPlus) {
12389 if (Record->isUnion()) {
12390 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
12391 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl());
12392 if (RDecl->getDefinition()) {
12393 // C++ [class.union]p1: An object of a class with a non-trivial
12394 // constructor, a non-trivial copy constructor, a non-trivial
12395 // destructor, or a non-trivial copy assignment operator
12396 // cannot be a member of a union, nor can an array of such
12398 if (CheckNontrivialField(NewFD))
12399 NewFD->setInvalidDecl();
12403 // C++ [class.union]p1: If a union contains a member of reference type,
12404 // the program is ill-formed, except when compiling with MSVC extensions
12406 if (EltTy->isReferenceType()) {
12407 Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ?
12408 diag::ext_union_member_of_reference_type :
12409 diag::err_union_member_of_reference_type)
12410 << NewFD->getDeclName() << EltTy;
12411 if (!getLangOpts().MicrosoftExt)
12412 NewFD->setInvalidDecl();
12417 // FIXME: We need to pass in the attributes given an AST
12418 // representation, not a parser representation.
12420 // FIXME: The current scope is almost... but not entirely... correct here.
12421 ProcessDeclAttributes(getCurScope(), NewFD, *D);
12423 if (NewFD->hasAttrs())
12424 CheckAlignasUnderalignment(NewFD);
12427 // In auto-retain/release, infer strong retension for fields of
12428 // retainable type.
12429 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewFD))
12430 NewFD->setInvalidDecl();
12432 if (T.isObjCGCWeak())
12433 Diag(Loc, diag::warn_attribute_weak_on_field);
12435 NewFD->setAccess(AS);
12439 bool Sema::CheckNontrivialField(FieldDecl *FD) {
12441 assert(getLangOpts().CPlusPlus && "valid check only for C++");
12443 if (FD->isInvalidDecl() || FD->getType()->isDependentType())
12446 QualType EltTy = Context.getBaseElementType(FD->getType());
12447 if (const RecordType *RT = EltTy->getAs<RecordType>()) {
12448 CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl());
12449 if (RDecl->getDefinition()) {
12450 // We check for copy constructors before constructors
12451 // because otherwise we'll never get complaints about
12452 // copy constructors.
12454 CXXSpecialMember member = CXXInvalid;
12455 // We're required to check for any non-trivial constructors. Since the
12456 // implicit default constructor is suppressed if there are any
12457 // user-declared constructors, we just need to check that there is a
12458 // trivial default constructor and a trivial copy constructor. (We don't
12459 // worry about move constructors here, since this is a C++98 check.)
12460 if (RDecl->hasNonTrivialCopyConstructor())
12461 member = CXXCopyConstructor;
12462 else if (!RDecl->hasTrivialDefaultConstructor())
12463 member = CXXDefaultConstructor;
12464 else if (RDecl->hasNonTrivialCopyAssignment())
12465 member = CXXCopyAssignment;
12466 else if (RDecl->hasNonTrivialDestructor())
12467 member = CXXDestructor;
12469 if (member != CXXInvalid) {
12470 if (!getLangOpts().CPlusPlus11 &&
12471 getLangOpts().ObjCAutoRefCount && RDecl->hasObjectMember()) {
12472 // Objective-C++ ARC: it is an error to have a non-trivial field of
12473 // a union. However, system headers in Objective-C programs
12474 // occasionally have Objective-C lifetime objects within unions,
12475 // and rather than cause the program to fail, we make those
12476 // members unavailable.
12477 SourceLocation Loc = FD->getLocation();
12478 if (getSourceManager().isInSystemHeader(Loc)) {
12479 if (!FD->hasAttr<UnavailableAttr>())
12480 FD->addAttr(UnavailableAttr::CreateImplicit(Context,
12481 "this system field has retaining ownership",
12487 Diag(FD->getLocation(), getLangOpts().CPlusPlus11 ?
12488 diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member :
12489 diag::err_illegal_union_or_anon_struct_member)
12490 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member;
12491 DiagnoseNontrivial(RDecl, member);
12492 return !getLangOpts().CPlusPlus11;
12500 /// TranslateIvarVisibility - Translate visibility from a token ID to an
12501 /// AST enum value.
12502 static ObjCIvarDecl::AccessControl
12503 TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) {
12504 switch (ivarVisibility) {
12505 default: llvm_unreachable("Unknown visitibility kind");
12506 case tok::objc_private: return ObjCIvarDecl::Private;
12507 case tok::objc_public: return ObjCIvarDecl::Public;
12508 case tok::objc_protected: return ObjCIvarDecl::Protected;
12509 case tok::objc_package: return ObjCIvarDecl::Package;
12513 /// ActOnIvar - Each ivar field of an objective-c class is passed into this
12514 /// in order to create an IvarDecl object for it.
12515 Decl *Sema::ActOnIvar(Scope *S,
12516 SourceLocation DeclStart,
12517 Declarator &D, Expr *BitfieldWidth,
12518 tok::ObjCKeywordKind Visibility) {
12520 IdentifierInfo *II = D.getIdentifier();
12521 Expr *BitWidth = (Expr*)BitfieldWidth;
12522 SourceLocation Loc = DeclStart;
12523 if (II) Loc = D.getIdentifierLoc();
12525 // FIXME: Unnamed fields can be handled in various different ways, for
12526 // example, unnamed unions inject all members into the struct namespace!
12528 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
12529 QualType T = TInfo->getType();
12532 // 6.7.2.1p3, 6.7.2.1p4
12533 BitWidth = VerifyBitField(Loc, II, T, /*IsMsStruct*/false, BitWidth).get();
12535 D.setInvalidType();
12542 if (T->isReferenceType()) {
12543 Diag(Loc, diag::err_ivar_reference_type);
12544 D.setInvalidType();
12546 // C99 6.7.2.1p8: A member of a structure or union may have any type other
12547 // than a variably modified type.
12548 else if (T->isVariablyModifiedType()) {
12549 Diag(Loc, diag::err_typecheck_ivar_variable_size);
12550 D.setInvalidType();
12553 // Get the visibility (access control) for this ivar.
12554 ObjCIvarDecl::AccessControl ac =
12555 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility)
12556 : ObjCIvarDecl::None;
12557 // Must set ivar's DeclContext to its enclosing interface.
12558 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(CurContext);
12559 if (!EnclosingDecl || EnclosingDecl->isInvalidDecl())
12561 ObjCContainerDecl *EnclosingContext;
12562 if (ObjCImplementationDecl *IMPDecl =
12563 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
12564 if (LangOpts.ObjCRuntime.isFragile()) {
12565 // Case of ivar declared in an implementation. Context is that of its class.
12566 EnclosingContext = IMPDecl->getClassInterface();
12567 assert(EnclosingContext && "Implementation has no class interface!");
12570 EnclosingContext = EnclosingDecl;
12572 if (ObjCCategoryDecl *CDecl =
12573 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
12574 if (LangOpts.ObjCRuntime.isFragile() || !CDecl->IsClassExtension()) {
12575 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension();
12579 EnclosingContext = EnclosingDecl;
12582 // Construct the decl.
12583 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext,
12584 DeclStart, Loc, II, T,
12585 TInfo, ac, (Expr *)BitfieldWidth);
12588 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName,
12590 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S)
12591 && !isa<TagDecl>(PrevDecl)) {
12592 Diag(Loc, diag::err_duplicate_member) << II;
12593 Diag(PrevDecl->getLocation(), diag::note_previous_declaration);
12594 NewID->setInvalidDecl();
12598 // Process attributes attached to the ivar.
12599 ProcessDeclAttributes(S, NewID, D);
12601 if (D.isInvalidType())
12602 NewID->setInvalidDecl();
12604 // In ARC, infer 'retaining' for ivars of retainable type.
12605 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewID))
12606 NewID->setInvalidDecl();
12608 if (D.getDeclSpec().isModulePrivateSpecified())
12609 NewID->setModulePrivate();
12612 // FIXME: When interfaces are DeclContexts, we'll need to add
12613 // these to the interface.
12615 IdResolver.AddDecl(NewID);
12618 if (LangOpts.ObjCRuntime.isNonFragile() &&
12619 !NewID->isInvalidDecl() && isa<ObjCInterfaceDecl>(EnclosingDecl))
12620 Diag(Loc, diag::warn_ivars_in_interface);
12625 /// ActOnLastBitfield - This routine handles synthesized bitfields rules for
12626 /// class and class extensions. For every class \@interface and class
12627 /// extension \@interface, if the last ivar is a bitfield of any type,
12628 /// then add an implicit `char :0` ivar to the end of that interface.
12629 void Sema::ActOnLastBitfield(SourceLocation DeclLoc,
12630 SmallVectorImpl<Decl *> &AllIvarDecls) {
12631 if (LangOpts.ObjCRuntime.isFragile() || AllIvarDecls.empty())
12634 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1];
12635 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl);
12637 if (!Ivar->isBitField() || Ivar->getBitWidthValue(Context) == 0)
12639 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CurContext);
12641 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(CurContext)) {
12642 if (!CD->IsClassExtension())
12645 // No need to add this to end of @implementation.
12649 // All conditions are met. Add a new bitfield to the tail end of ivars.
12650 llvm::APInt Zero(Context.getTypeSize(Context.IntTy), 0);
12651 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.IntTy, DeclLoc);
12653 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(CurContext),
12654 DeclLoc, DeclLoc, nullptr,
12656 Context.getTrivialTypeSourceInfo(Context.CharTy,
12658 ObjCIvarDecl::Private, BW,
12660 AllIvarDecls.push_back(Ivar);
12663 void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
12664 ArrayRef<Decl *> Fields, SourceLocation LBrac,
12665 SourceLocation RBrac, AttributeList *Attr) {
12666 assert(EnclosingDecl && "missing record or interface decl");
12668 // If this is an Objective-C @implementation or category and we have
12669 // new fields here we should reset the layout of the interface since
12670 // it will now change.
12671 if (!Fields.empty() && isa<ObjCContainerDecl>(EnclosingDecl)) {
12672 ObjCContainerDecl *DC = cast<ObjCContainerDecl>(EnclosingDecl);
12673 switch (DC->getKind()) {
12675 case Decl::ObjCCategory:
12676 Context.ResetObjCLayout(cast<ObjCCategoryDecl>(DC)->getClassInterface());
12678 case Decl::ObjCImplementation:
12680 ResetObjCLayout(cast<ObjCImplementationDecl>(DC)->getClassInterface());
12685 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl);
12687 // Start counting up the number of named members; make sure to include
12688 // members of anonymous structs and unions in the total.
12689 unsigned NumNamedMembers = 0;
12691 for (const auto *I : Record->decls()) {
12692 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
12693 if (IFD->getDeclName())
12698 // Verify that all the fields are okay.
12699 SmallVector<FieldDecl*, 32> RecFields;
12701 bool ARCErrReported = false;
12702 for (ArrayRef<Decl *>::iterator i = Fields.begin(), end = Fields.end();
12704 FieldDecl *FD = cast<FieldDecl>(*i);
12706 // Get the type for the field.
12707 const Type *FDTy = FD->getType().getTypePtr();
12709 if (!FD->isAnonymousStructOrUnion()) {
12710 // Remember all fields written by the user.
12711 RecFields.push_back(FD);
12714 // If the field is already invalid for some reason, don't emit more
12715 // diagnostics about it.
12716 if (FD->isInvalidDecl()) {
12717 EnclosingDecl->setInvalidDecl();
12722 // A structure or union shall not contain a member with
12723 // incomplete or function type (hence, a structure shall not
12724 // contain an instance of itself, but may contain a pointer to
12725 // an instance of itself), except that the last member of a
12726 // structure with more than one named member may have incomplete
12727 // array type; such a structure (and any union containing,
12728 // possibly recursively, a member that is such a structure)
12729 // shall not be a member of a structure or an element of an
12731 if (FDTy->isFunctionType()) {
12732 // Field declared as a function.
12733 Diag(FD->getLocation(), diag::err_field_declared_as_function)
12734 << FD->getDeclName();
12735 FD->setInvalidDecl();
12736 EnclosingDecl->setInvalidDecl();
12738 } else if (FDTy->isIncompleteArrayType() && Record &&
12739 ((i + 1 == Fields.end() && !Record->isUnion()) ||
12740 ((getLangOpts().MicrosoftExt ||
12741 getLangOpts().CPlusPlus) &&
12742 (i + 1 == Fields.end() || Record->isUnion())))) {
12743 // Flexible array member.
12744 // Microsoft and g++ is more permissive regarding flexible array.
12745 // It will accept flexible array in union and also
12746 // as the sole element of a struct/class.
12747 unsigned DiagID = 0;
12748 if (Record->isUnion())
12749 DiagID = getLangOpts().MicrosoftExt
12750 ? diag::ext_flexible_array_union_ms
12751 : getLangOpts().CPlusPlus
12752 ? diag::ext_flexible_array_union_gnu
12753 : diag::err_flexible_array_union;
12754 else if (Fields.size() == 1)
12755 DiagID = getLangOpts().MicrosoftExt
12756 ? diag::ext_flexible_array_empty_aggregate_ms
12757 : getLangOpts().CPlusPlus
12758 ? diag::ext_flexible_array_empty_aggregate_gnu
12759 : NumNamedMembers < 1
12760 ? diag::err_flexible_array_empty_aggregate
12764 Diag(FD->getLocation(), DiagID) << FD->getDeclName()
12765 << Record->getTagKind();
12766 // While the layout of types that contain virtual bases is not specified
12767 // by the C++ standard, both the Itanium and Microsoft C++ ABIs place
12768 // virtual bases after the derived members. This would make a flexible
12769 // array member declared at the end of an object not adjacent to the end
12771 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record))
12772 if (RD->getNumVBases() != 0)
12773 Diag(FD->getLocation(), diag::err_flexible_array_virtual_base)
12774 << FD->getDeclName() << Record->getTagKind();
12775 if (!getLangOpts().C99)
12776 Diag(FD->getLocation(), diag::ext_c99_flexible_array_member)
12777 << FD->getDeclName() << Record->getTagKind();
12779 // If the element type has a non-trivial destructor, we would not
12780 // implicitly destroy the elements, so disallow it for now.
12782 // FIXME: GCC allows this. We should probably either implicitly delete
12783 // the destructor of the containing class, or just allow this.
12784 QualType BaseElem = Context.getBaseElementType(FD->getType());
12785 if (!BaseElem->isDependentType() && BaseElem.isDestructedType()) {
12786 Diag(FD->getLocation(), diag::err_flexible_array_has_nontrivial_dtor)
12787 << FD->getDeclName() << FD->getType();
12788 FD->setInvalidDecl();
12789 EnclosingDecl->setInvalidDecl();
12792 // Okay, we have a legal flexible array member at the end of the struct.
12793 Record->setHasFlexibleArrayMember(true);
12794 } else if (!FDTy->isDependentType() &&
12795 RequireCompleteType(FD->getLocation(), FD->getType(),
12796 diag::err_field_incomplete)) {
12798 FD->setInvalidDecl();
12799 EnclosingDecl->setInvalidDecl();
12801 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) {
12802 if (Record && FDTTy->getDecl()->hasFlexibleArrayMember()) {
12803 // A type which contains a flexible array member is considered to be a
12804 // flexible array member.
12805 Record->setHasFlexibleArrayMember(true);
12806 if (!Record->isUnion()) {
12807 // If this is a struct/class and this is not the last element, reject
12808 // it. Note that GCC supports variable sized arrays in the middle of
12810 if (i + 1 != Fields.end())
12811 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct)
12812 << FD->getDeclName() << FD->getType();
12814 // We support flexible arrays at the end of structs in
12815 // other structs as an extension.
12816 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct)
12817 << FD->getDeclName();
12821 if (isa<ObjCContainerDecl>(EnclosingDecl) &&
12822 RequireNonAbstractType(FD->getLocation(), FD->getType(),
12823 diag::err_abstract_type_in_decl,
12824 AbstractIvarType)) {
12825 // Ivars can not have abstract class types
12826 FD->setInvalidDecl();
12828 if (Record && FDTTy->getDecl()->hasObjectMember())
12829 Record->setHasObjectMember(true);
12830 if (Record && FDTTy->getDecl()->hasVolatileMember())
12831 Record->setHasVolatileMember(true);
12832 } else if (FDTy->isObjCObjectType()) {
12833 /// A field cannot be an Objective-c object
12834 Diag(FD->getLocation(), diag::err_statically_allocated_object)
12835 << FixItHint::CreateInsertion(FD->getLocation(), "*");
12836 QualType T = Context.getObjCObjectPointerType(FD->getType());
12838 } else if (getLangOpts().ObjCAutoRefCount && Record && !ARCErrReported &&
12839 (!getLangOpts().CPlusPlus || Record->isUnion())) {
12840 // It's an error in ARC if a field has lifetime.
12841 // We don't want to report this in a system header, though,
12842 // so we just make the field unavailable.
12843 // FIXME: that's really not sufficient; we need to make the type
12844 // itself invalid to, say, initialize or copy.
12845 QualType T = FD->getType();
12846 Qualifiers::ObjCLifetime lifetime = T.getObjCLifetime();
12847 if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone) {
12848 SourceLocation loc = FD->getLocation();
12849 if (getSourceManager().isInSystemHeader(loc)) {
12850 if (!FD->hasAttr<UnavailableAttr>()) {
12851 FD->addAttr(UnavailableAttr::CreateImplicit(Context,
12852 "this system field has retaining ownership",
12856 Diag(FD->getLocation(), diag::err_arc_objc_object_in_tag)
12857 << T->isBlockPointerType() << Record->getTagKind();
12859 ARCErrReported = true;
12861 } else if (getLangOpts().ObjC1 &&
12862 getLangOpts().getGC() != LangOptions::NonGC &&
12863 Record && !Record->hasObjectMember()) {
12864 if (FD->getType()->isObjCObjectPointerType() ||
12865 FD->getType().isObjCGCStrong())
12866 Record->setHasObjectMember(true);
12867 else if (Context.getAsArrayType(FD->getType())) {
12868 QualType BaseType = Context.getBaseElementType(FD->getType());
12869 if (BaseType->isRecordType() &&
12870 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember())
12871 Record->setHasObjectMember(true);
12872 else if (BaseType->isObjCObjectPointerType() ||
12873 BaseType.isObjCGCStrong())
12874 Record->setHasObjectMember(true);
12877 if (Record && FD->getType().isVolatileQualified())
12878 Record->setHasVolatileMember(true);
12879 // Keep track of the number of named members.
12880 if (FD->getIdentifier())
12884 // Okay, we successfully defined 'Record'.
12886 bool Completed = false;
12887 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) {
12888 if (!CXXRecord->isInvalidDecl()) {
12889 // Set access bits correctly on the directly-declared conversions.
12890 for (CXXRecordDecl::conversion_iterator
12891 I = CXXRecord->conversion_begin(),
12892 E = CXXRecord->conversion_end(); I != E; ++I)
12893 I.setAccess((*I)->getAccess());
12895 if (!CXXRecord->isDependentType()) {
12896 if (CXXRecord->hasUserDeclaredDestructor()) {
12897 // Adjust user-defined destructor exception spec.
12898 if (getLangOpts().CPlusPlus11)
12899 AdjustDestructorExceptionSpec(CXXRecord,
12900 CXXRecord->getDestructor());
12903 // Add any implicitly-declared members to this class.
12904 AddImplicitlyDeclaredMembersToClass(CXXRecord);
12906 // If we have virtual base classes, we may end up finding multiple
12907 // final overriders for a given virtual function. Check for this
12909 if (CXXRecord->getNumVBases()) {
12910 CXXFinalOverriderMap FinalOverriders;
12911 CXXRecord->getFinalOverriders(FinalOverriders);
12913 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
12914 MEnd = FinalOverriders.end();
12916 for (OverridingMethods::iterator SO = M->second.begin(),
12917 SOEnd = M->second.end();
12918 SO != SOEnd; ++SO) {
12919 assert(SO->second.size() > 0 &&
12920 "Virtual function without overridding functions?");
12921 if (SO->second.size() == 1)
12924 // C++ [class.virtual]p2:
12925 // In a derived class, if a virtual member function of a base
12926 // class subobject has more than one final overrider the
12927 // program is ill-formed.
12928 Diag(Record->getLocation(), diag::err_multiple_final_overriders)
12929 << (const NamedDecl *)M->first << Record;
12930 Diag(M->first->getLocation(),
12931 diag::note_overridden_virtual_function);
12932 for (OverridingMethods::overriding_iterator
12933 OM = SO->second.begin(),
12934 OMEnd = SO->second.end();
12936 Diag(OM->Method->getLocation(), diag::note_final_overrider)
12937 << (const NamedDecl *)M->first << OM->Method->getParent();
12939 Record->setInvalidDecl();
12942 CXXRecord->completeDefinition(&FinalOverriders);
12950 Record->completeDefinition();
12952 if (Record->hasAttrs()) {
12953 CheckAlignasUnderalignment(Record);
12955 if (const MSInheritanceAttr *IA = Record->getAttr<MSInheritanceAttr>())
12956 checkMSInheritanceAttrOnDefinition(cast<CXXRecordDecl>(Record),
12957 IA->getRange(), IA->getBestCase(),
12958 IA->getSemanticSpelling());
12961 // Check if the structure/union declaration is a type that can have zero
12962 // size in C. For C this is a language extension, for C++ it may cause
12963 // compatibility problems.
12964 bool CheckForZeroSize;
12965 if (!getLangOpts().CPlusPlus) {
12966 CheckForZeroSize = true;
12968 // For C++ filter out types that cannot be referenced in C code.
12969 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record);
12971 CXXRecord->getLexicalDeclContext()->isExternCContext() &&
12972 !CXXRecord->isDependentType() &&
12973 CXXRecord->isCLike();
12975 if (CheckForZeroSize) {
12976 bool ZeroSize = true;
12977 bool IsEmpty = true;
12978 unsigned NonBitFields = 0;
12979 for (RecordDecl::field_iterator I = Record->field_begin(),
12980 E = Record->field_end();
12981 (NonBitFields == 0 || ZeroSize) && I != E; ++I) {
12983 if (I->isUnnamedBitfield()) {
12984 if (I->getBitWidthValue(Context) > 0)
12988 QualType FieldType = I->getType();
12989 if (FieldType->isIncompleteType() ||
12990 !Context.getTypeSizeInChars(FieldType).isZero())
12995 // Empty structs are an extension in C (C99 6.7.2.1p7). They are
12996 // allowed in C++, but warn if its declaration is inside
12997 // extern "C" block.
12999 Diag(RecLoc, getLangOpts().CPlusPlus ?
13000 diag::warn_zero_size_struct_union_in_extern_c :
13001 diag::warn_zero_size_struct_union_compat)
13002 << IsEmpty << Record->isUnion() << (NonBitFields > 1);
13005 // Structs without named members are extension in C (C99 6.7.2.1p7),
13006 // but are accepted by GCC.
13007 if (NonBitFields == 0 && !getLangOpts().CPlusPlus) {
13008 Diag(RecLoc, IsEmpty ? diag::ext_empty_struct_union :
13009 diag::ext_no_named_members_in_struct_union)
13010 << Record->isUnion();
13014 ObjCIvarDecl **ClsFields =
13015 reinterpret_cast<ObjCIvarDecl**>(RecFields.data());
13016 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) {
13017 ID->setEndOfDefinitionLoc(RBrac);
13018 // Add ivar's to class's DeclContext.
13019 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
13020 ClsFields[i]->setLexicalDeclContext(ID);
13021 ID->addDecl(ClsFields[i]);
13023 // Must enforce the rule that ivars in the base classes may not be
13025 if (ID->getSuperClass())
13026 DiagnoseDuplicateIvars(ID, ID->getSuperClass());
13027 } else if (ObjCImplementationDecl *IMPDecl =
13028 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) {
13029 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl");
13030 for (unsigned I = 0, N = RecFields.size(); I != N; ++I)
13031 // Ivar declared in @implementation never belongs to the implementation.
13032 // Only it is in implementation's lexical context.
13033 ClsFields[I]->setLexicalDeclContext(IMPDecl);
13034 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac);
13035 IMPDecl->setIvarLBraceLoc(LBrac);
13036 IMPDecl->setIvarRBraceLoc(RBrac);
13037 } else if (ObjCCategoryDecl *CDecl =
13038 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) {
13039 // case of ivars in class extension; all other cases have been
13040 // reported as errors elsewhere.
13041 // FIXME. Class extension does not have a LocEnd field.
13042 // CDecl->setLocEnd(RBrac);
13043 // Add ivar's to class extension's DeclContext.
13044 // Diagnose redeclaration of private ivars.
13045 ObjCInterfaceDecl *IDecl = CDecl->getClassInterface();
13046 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
13048 if (const ObjCIvarDecl *ClsIvar =
13049 IDecl->getIvarDecl(ClsFields[i]->getIdentifier())) {
13050 Diag(ClsFields[i]->getLocation(),
13051 diag::err_duplicate_ivar_declaration);
13052 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
13055 for (const auto *Ext : IDecl->known_extensions()) {
13056 if (const ObjCIvarDecl *ClsExtIvar
13057 = Ext->getIvarDecl(ClsFields[i]->getIdentifier())) {
13058 Diag(ClsFields[i]->getLocation(),
13059 diag::err_duplicate_ivar_declaration);
13060 Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
13065 ClsFields[i]->setLexicalDeclContext(CDecl);
13066 CDecl->addDecl(ClsFields[i]);
13068 CDecl->setIvarLBraceLoc(LBrac);
13069 CDecl->setIvarRBraceLoc(RBrac);
13074 ProcessDeclAttributeList(S, Record, Attr);
13077 /// \brief Determine whether the given integral value is representable within
13078 /// the given type T.
13079 static bool isRepresentableIntegerValue(ASTContext &Context,
13080 llvm::APSInt &Value,
13082 assert(T->isIntegralType(Context) && "Integral type required!");
13083 unsigned BitWidth = Context.getIntWidth(T);
13085 if (Value.isUnsigned() || Value.isNonNegative()) {
13086 if (T->isSignedIntegerOrEnumerationType())
13088 return Value.getActiveBits() <= BitWidth;
13090 return Value.getMinSignedBits() <= BitWidth;
13093 // \brief Given an integral type, return the next larger integral type
13094 // (or a NULL type of no such type exists).
13095 static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) {
13096 // FIXME: Int128/UInt128 support, which also needs to be introduced into
13097 // enum checking below.
13098 assert(T->isIntegralType(Context) && "Integral type required!");
13099 const unsigned NumTypes = 4;
13100 QualType SignedIntegralTypes[NumTypes] = {
13101 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy
13103 QualType UnsignedIntegralTypes[NumTypes] = {
13104 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy,
13105 Context.UnsignedLongLongTy
13108 unsigned BitWidth = Context.getTypeSize(T);
13109 QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes
13110 : UnsignedIntegralTypes;
13111 for (unsigned I = 0; I != NumTypes; ++I)
13112 if (Context.getTypeSize(Types[I]) > BitWidth)
13118 EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum,
13119 EnumConstantDecl *LastEnumConst,
13120 SourceLocation IdLoc,
13121 IdentifierInfo *Id,
13123 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
13124 llvm::APSInt EnumVal(IntWidth);
13127 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue))
13131 Val = DefaultLvalueConversion(Val).get();
13134 if (Enum->isDependentType() || Val->isTypeDependent())
13135 EltTy = Context.DependentTy;
13137 SourceLocation ExpLoc;
13138 if (getLangOpts().CPlusPlus11 && Enum->isFixed() &&
13139 !getLangOpts().MSVCCompat) {
13140 // C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the
13141 // constant-expression in the enumerator-definition shall be a converted
13142 // constant expression of the underlying type.
13143 EltTy = Enum->getIntegerType();
13144 ExprResult Converted =
13145 CheckConvertedConstantExpression(Val, EltTy, EnumVal,
13147 if (Converted.isInvalid())
13150 Val = Converted.get();
13151 } else if (!Val->isValueDependent() &&
13152 !(Val = VerifyIntegerConstantExpression(Val,
13153 &EnumVal).get())) {
13154 // C99 6.7.2.2p2: Make sure we have an integer constant expression.
13156 if (Enum->isFixed()) {
13157 EltTy = Enum->getIntegerType();
13159 // In Obj-C and Microsoft mode, require the enumeration value to be
13160 // representable in the underlying type of the enumeration. In C++11,
13161 // we perform a non-narrowing conversion as part of converted constant
13162 // expression checking.
13163 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
13164 if (getLangOpts().MSVCCompat) {
13165 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy;
13166 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
13168 Diag(IdLoc, diag::err_enumerator_too_large) << EltTy;
13170 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
13171 } else if (getLangOpts().CPlusPlus) {
13172 // C++11 [dcl.enum]p5:
13173 // If the underlying type is not fixed, the type of each enumerator
13174 // is the type of its initializing value:
13175 // - If an initializer is specified for an enumerator, the
13176 // initializing value has the same type as the expression.
13177 EltTy = Val->getType();
13180 // The expression that defines the value of an enumeration constant
13181 // shall be an integer constant expression that has a value
13182 // representable as an int.
13184 // Complain if the value is not representable in an int.
13185 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy))
13186 Diag(IdLoc, diag::ext_enum_value_not_int)
13187 << EnumVal.toString(10) << Val->getSourceRange()
13188 << (EnumVal.isUnsigned() || EnumVal.isNonNegative());
13189 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) {
13190 // Force the type of the expression to 'int'.
13191 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).get();
13193 EltTy = Val->getType();
13200 if (Enum->isDependentType())
13201 EltTy = Context.DependentTy;
13202 else if (!LastEnumConst) {
13203 // C++0x [dcl.enum]p5:
13204 // If the underlying type is not fixed, the type of each enumerator
13205 // is the type of its initializing value:
13206 // - If no initializer is specified for the first enumerator, the
13207 // initializing value has an unspecified integral type.
13209 // GCC uses 'int' for its unspecified integral type, as does
13211 if (Enum->isFixed()) {
13212 EltTy = Enum->getIntegerType();
13215 EltTy = Context.IntTy;
13218 // Assign the last value + 1.
13219 EnumVal = LastEnumConst->getInitVal();
13221 EltTy = LastEnumConst->getType();
13223 // Check for overflow on increment.
13224 if (EnumVal < LastEnumConst->getInitVal()) {
13225 // C++0x [dcl.enum]p5:
13226 // If the underlying type is not fixed, the type of each enumerator
13227 // is the type of its initializing value:
13229 // - Otherwise the type of the initializing value is the same as
13230 // the type of the initializing value of the preceding enumerator
13231 // unless the incremented value is not representable in that type,
13232 // in which case the type is an unspecified integral type
13233 // sufficient to contain the incremented value. If no such type
13234 // exists, the program is ill-formed.
13235 QualType T = getNextLargerIntegralType(Context, EltTy);
13236 if (T.isNull() || Enum->isFixed()) {
13237 // There is no integral type larger enough to represent this
13238 // value. Complain, then allow the value to wrap around.
13239 EnumVal = LastEnumConst->getInitVal();
13240 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2);
13242 if (Enum->isFixed())
13243 // When the underlying type is fixed, this is ill-formed.
13244 Diag(IdLoc, diag::err_enumerator_wrapped)
13245 << EnumVal.toString(10)
13248 Diag(IdLoc, diag::ext_enumerator_increment_too_large)
13249 << EnumVal.toString(10);
13254 // Retrieve the last enumerator's value, extent that type to the
13255 // type that is supposed to be large enough to represent the incremented
13256 // value, then increment.
13257 EnumVal = LastEnumConst->getInitVal();
13258 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
13259 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy));
13262 // If we're not in C++, diagnose the overflow of enumerator values,
13263 // which in C99 means that the enumerator value is not representable in
13264 // an int (C99 6.7.2.2p2). However, we support GCC's extension that
13265 // permits enumerator values that are representable in some larger
13267 if (!getLangOpts().CPlusPlus && !T.isNull())
13268 Diag(IdLoc, diag::warn_enum_value_overflow);
13269 } else if (!getLangOpts().CPlusPlus &&
13270 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
13271 // Enforce C99 6.7.2.2p2 even when we compute the next value.
13272 Diag(IdLoc, diag::ext_enum_value_not_int)
13273 << EnumVal.toString(10) << 1;
13278 if (!EltTy->isDependentType()) {
13279 // Make the enumerator value match the signedness and size of the
13280 // enumerator's type.
13281 EnumVal = EnumVal.extOrTrunc(Context.getIntWidth(EltTy));
13282 EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType());
13285 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy,
13290 Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst,
13291 SourceLocation IdLoc, IdentifierInfo *Id,
13292 AttributeList *Attr,
13293 SourceLocation EqualLoc, Expr *Val) {
13294 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl);
13295 EnumConstantDecl *LastEnumConst =
13296 cast_or_null<EnumConstantDecl>(lastEnumConst);
13298 // The scope passed in may not be a decl scope. Zip up the scope tree until
13299 // we find one that is.
13300 S = getNonFieldDeclScope(S);
13302 // Verify that there isn't already something declared with this name in this
13304 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName,
13306 if (PrevDecl && PrevDecl->isTemplateParameter()) {
13307 // Maybe we will complain about the shadowed template parameter.
13308 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl);
13309 // Just pretend that we didn't see the previous declaration.
13310 PrevDecl = nullptr;
13314 // When in C++, we may get a TagDecl with the same name; in this case the
13315 // enum constant will 'hide' the tag.
13316 assert((getLangOpts().CPlusPlus || !isa<TagDecl>(PrevDecl)) &&
13317 "Received TagDecl when not in C++!");
13318 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) {
13319 if (isa<EnumConstantDecl>(PrevDecl))
13320 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id;
13322 Diag(IdLoc, diag::err_redefinition) << Id;
13323 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
13328 // C++ [class.mem]p15:
13329 // If T is the name of a class, then each of the following shall have a name
13330 // different from T:
13331 // - every enumerator of every member of class T that is an unscoped
13333 if (CXXRecordDecl *Record
13334 = dyn_cast<CXXRecordDecl>(
13335 TheEnumDecl->getDeclContext()->getRedeclContext()))
13336 if (!TheEnumDecl->isScoped() &&
13337 Record->getIdentifier() && Record->getIdentifier() == Id)
13338 Diag(IdLoc, diag::err_member_name_of_class) << Id;
13340 EnumConstantDecl *New =
13341 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val);
13344 // Process attributes.
13345 if (Attr) ProcessDeclAttributeList(S, New, Attr);
13347 // Register this decl in the current scope stack.
13348 New->setAccess(TheEnumDecl->getAccess());
13349 PushOnScopeChains(New, S);
13352 ActOnDocumentableDecl(New);
13357 // Returns true when the enum initial expression does not trigger the
13358 // duplicate enum warning. A few common cases are exempted as follows:
13359 // Element2 = Element1
13360 // Element2 = Element1 + 1
13361 // Element2 = Element1 - 1
13362 // Where Element2 and Element1 are from the same enum.
13363 static bool ValidDuplicateEnum(EnumConstantDecl *ECD, EnumDecl *Enum) {
13364 Expr *InitExpr = ECD->getInitExpr();
13367 InitExpr = InitExpr->IgnoreImpCasts();
13369 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(InitExpr)) {
13370 if (!BO->isAdditiveOp())
13372 IntegerLiteral *IL = dyn_cast<IntegerLiteral>(BO->getRHS());
13375 if (IL->getValue() != 1)
13378 InitExpr = BO->getLHS();
13381 // This checks if the elements are from the same enum.
13382 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InitExpr);
13386 EnumConstantDecl *EnumConstant = dyn_cast<EnumConstantDecl>(DRE->getDecl());
13390 if (cast<EnumDecl>(TagDecl::castFromDeclContext(ECD->getDeclContext())) !=
13399 bool isTombstoneOrEmptyKey;
13400 DupKey(int64_t val, bool isTombstoneOrEmptyKey)
13401 : val(val), isTombstoneOrEmptyKey(isTombstoneOrEmptyKey) {}
13404 static DupKey GetDupKey(const llvm::APSInt& Val) {
13405 return DupKey(Val.isSigned() ? Val.getSExtValue() : Val.getZExtValue(),
13409 struct DenseMapInfoDupKey {
13410 static DupKey getEmptyKey() { return DupKey(0, true); }
13411 static DupKey getTombstoneKey() { return DupKey(1, true); }
13412 static unsigned getHashValue(const DupKey Key) {
13413 return (unsigned)(Key.val * 37);
13415 static bool isEqual(const DupKey& LHS, const DupKey& RHS) {
13416 return LHS.isTombstoneOrEmptyKey == RHS.isTombstoneOrEmptyKey &&
13417 LHS.val == RHS.val;
13421 // Emits a warning when an element is implicitly set a value that
13422 // a previous element has already been set to.
13423 static void CheckForDuplicateEnumValues(Sema &S, ArrayRef<Decl *> Elements,
13425 QualType EnumType) {
13426 if (S.Diags.isIgnored(diag::warn_duplicate_enum_values, Enum->getLocation()))
13428 // Avoid anonymous enums
13429 if (!Enum->getIdentifier())
13432 // Only check for small enums.
13433 if (Enum->getNumPositiveBits() > 63 || Enum->getNumNegativeBits() > 64)
13436 typedef SmallVector<EnumConstantDecl *, 3> ECDVector;
13437 typedef SmallVector<ECDVector *, 3> DuplicatesVector;
13439 typedef llvm::PointerUnion<EnumConstantDecl*, ECDVector*> DeclOrVector;
13440 typedef llvm::DenseMap<DupKey, DeclOrVector, DenseMapInfoDupKey>
13443 DuplicatesVector DupVector;
13444 ValueToVectorMap EnumMap;
13446 // Populate the EnumMap with all values represented by enum constants without
13448 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
13449 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]);
13451 // Null EnumConstantDecl means a previous diagnostic has been emitted for
13452 // this constant. Skip this enum since it may be ill-formed.
13457 if (ECD->getInitExpr())
13460 DupKey Key = GetDupKey(ECD->getInitVal());
13461 DeclOrVector &Entry = EnumMap[Key];
13463 // First time encountering this value.
13464 if (Entry.isNull())
13468 // Create vectors for any values that has duplicates.
13469 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
13470 EnumConstantDecl *ECD = cast<EnumConstantDecl>(Elements[i]);
13471 if (!ValidDuplicateEnum(ECD, Enum))
13474 DupKey Key = GetDupKey(ECD->getInitVal());
13476 DeclOrVector& Entry = EnumMap[Key];
13477 if (Entry.isNull())
13480 if (EnumConstantDecl *D = Entry.dyn_cast<EnumConstantDecl*>()) {
13481 // Ensure constants are different.
13485 // Create new vector and push values onto it.
13486 ECDVector *Vec = new ECDVector();
13488 Vec->push_back(ECD);
13490 // Update entry to point to the duplicates vector.
13493 // Store the vector somewhere we can consult later for quick emission of
13495 DupVector.push_back(Vec);
13499 ECDVector *Vec = Entry.get<ECDVector*>();
13500 // Make sure constants are not added more than once.
13501 if (*Vec->begin() == ECD)
13504 Vec->push_back(ECD);
13507 // Emit diagnostics.
13508 for (DuplicatesVector::iterator DupVectorIter = DupVector.begin(),
13509 DupVectorEnd = DupVector.end();
13510 DupVectorIter != DupVectorEnd; ++DupVectorIter) {
13511 ECDVector *Vec = *DupVectorIter;
13512 assert(Vec->size() > 1 && "ECDVector should have at least 2 elements.");
13514 // Emit warning for one enum constant.
13515 ECDVector::iterator I = Vec->begin();
13516 S.Diag((*I)->getLocation(), diag::warn_duplicate_enum_values)
13517 << (*I)->getName() << (*I)->getInitVal().toString(10)
13518 << (*I)->getSourceRange();
13521 // Emit one note for each of the remaining enum constants with
13523 for (ECDVector::iterator E = Vec->end(); I != E; ++I)
13524 S.Diag((*I)->getLocation(), diag::note_duplicate_element)
13525 << (*I)->getName() << (*I)->getInitVal().toString(10)
13526 << (*I)->getSourceRange();
13531 void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
13532 SourceLocation RBraceLoc, Decl *EnumDeclX,
13533 ArrayRef<Decl *> Elements,
13534 Scope *S, AttributeList *Attr) {
13535 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX);
13536 QualType EnumType = Context.getTypeDeclType(Enum);
13539 ProcessDeclAttributeList(S, Enum, Attr);
13541 if (Enum->isDependentType()) {
13542 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
13543 EnumConstantDecl *ECD =
13544 cast_or_null<EnumConstantDecl>(Elements[i]);
13545 if (!ECD) continue;
13547 ECD->setType(EnumType);
13550 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0);
13554 // TODO: If the result value doesn't fit in an int, it must be a long or long
13555 // long value. ISO C does not support this, but GCC does as an extension,
13557 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
13558 unsigned CharWidth = Context.getTargetInfo().getCharWidth();
13559 unsigned ShortWidth = Context.getTargetInfo().getShortWidth();
13561 // Verify that all the values are okay, compute the size of the values, and
13562 // reverse the list.
13563 unsigned NumNegativeBits = 0;
13564 unsigned NumPositiveBits = 0;
13566 // Keep track of whether all elements have type int.
13567 bool AllElementsInt = true;
13569 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
13570 EnumConstantDecl *ECD =
13571 cast_or_null<EnumConstantDecl>(Elements[i]);
13572 if (!ECD) continue; // Already issued a diagnostic.
13574 const llvm::APSInt &InitVal = ECD->getInitVal();
13576 // Keep track of the size of positive and negative values.
13577 if (InitVal.isUnsigned() || InitVal.isNonNegative())
13578 NumPositiveBits = std::max(NumPositiveBits,
13579 (unsigned)InitVal.getActiveBits());
13581 NumNegativeBits = std::max(NumNegativeBits,
13582 (unsigned)InitVal.getMinSignedBits());
13584 // Keep track of whether every enum element has type int (very commmon).
13585 if (AllElementsInt)
13586 AllElementsInt = ECD->getType() == Context.IntTy;
13589 // Figure out the type that should be used for this enum.
13591 unsigned BestWidth;
13593 // C++0x N3000 [conv.prom]p3:
13594 // An rvalue of an unscoped enumeration type whose underlying
13595 // type is not fixed can be converted to an rvalue of the first
13596 // of the following types that can represent all the values of
13597 // the enumeration: int, unsigned int, long int, unsigned long
13598 // int, long long int, or unsigned long long int.
13600 // An identifier declared as an enumeration constant has type int.
13601 // The C99 rule is modified by a gcc extension
13602 QualType BestPromotionType;
13604 bool Packed = Enum->hasAttr<PackedAttr>();
13605 // -fshort-enums is the equivalent to specifying the packed attribute on all
13606 // enum definitions.
13607 if (LangOpts.ShortEnums)
13610 if (Enum->isFixed()) {
13611 BestType = Enum->getIntegerType();
13612 if (BestType->isPromotableIntegerType())
13613 BestPromotionType = Context.getPromotedIntegerType(BestType);
13615 BestPromotionType = BestType;
13616 // We don't need to set BestWidth, because BestType is going to be the type
13617 // of the enumerators, but we do anyway because otherwise some compilers
13618 // warn that it might be used uninitialized.
13619 BestWidth = CharWidth;
13621 else if (NumNegativeBits) {
13622 // If there is a negative value, figure out the smallest integer type (of
13623 // int/long/longlong) that fits.
13624 // If it's packed, check also if it fits a char or a short.
13625 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
13626 BestType = Context.SignedCharTy;
13627 BestWidth = CharWidth;
13628 } else if (Packed && NumNegativeBits <= ShortWidth &&
13629 NumPositiveBits < ShortWidth) {
13630 BestType = Context.ShortTy;
13631 BestWidth = ShortWidth;
13632 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
13633 BestType = Context.IntTy;
13634 BestWidth = IntWidth;
13636 BestWidth = Context.getTargetInfo().getLongWidth();
13638 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) {
13639 BestType = Context.LongTy;
13641 BestWidth = Context.getTargetInfo().getLongLongWidth();
13643 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth)
13644 Diag(Enum->getLocation(), diag::ext_enum_too_large);
13645 BestType = Context.LongLongTy;
13648 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType);
13650 // If there is no negative value, figure out the smallest type that fits
13651 // all of the enumerator values.
13652 // If it's packed, check also if it fits a char or a short.
13653 if (Packed && NumPositiveBits <= CharWidth) {
13654 BestType = Context.UnsignedCharTy;
13655 BestPromotionType = Context.IntTy;
13656 BestWidth = CharWidth;
13657 } else if (Packed && NumPositiveBits <= ShortWidth) {
13658 BestType = Context.UnsignedShortTy;
13659 BestPromotionType = Context.IntTy;
13660 BestWidth = ShortWidth;
13661 } else if (NumPositiveBits <= IntWidth) {
13662 BestType = Context.UnsignedIntTy;
13663 BestWidth = IntWidth;
13665 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
13666 ? Context.UnsignedIntTy : Context.IntTy;
13667 } else if (NumPositiveBits <=
13668 (BestWidth = Context.getTargetInfo().getLongWidth())) {
13669 BestType = Context.UnsignedLongTy;
13671 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
13672 ? Context.UnsignedLongTy : Context.LongTy;
13674 BestWidth = Context.getTargetInfo().getLongLongWidth();
13675 assert(NumPositiveBits <= BestWidth &&
13676 "How could an initializer get larger than ULL?");
13677 BestType = Context.UnsignedLongLongTy;
13679 = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus)
13680 ? Context.UnsignedLongLongTy : Context.LongLongTy;
13684 // Loop over all of the enumerator constants, changing their types to match
13685 // the type of the enum if needed.
13686 for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
13687 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]);
13688 if (!ECD) continue; // Already issued a diagnostic.
13690 // Standard C says the enumerators have int type, but we allow, as an
13691 // extension, the enumerators to be larger than int size. If each
13692 // enumerator value fits in an int, type it as an int, otherwise type it the
13693 // same as the enumerator decl itself. This means that in "enum { X = 1U }"
13694 // that X has type 'int', not 'unsigned'.
13696 // Determine whether the value fits into an int.
13697 llvm::APSInt InitVal = ECD->getInitVal();
13699 // If it fits into an integer type, force it. Otherwise force it to match
13700 // the enum decl type.
13704 if (!getLangOpts().CPlusPlus &&
13705 !Enum->isFixed() &&
13706 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) {
13707 NewTy = Context.IntTy;
13708 NewWidth = IntWidth;
13710 } else if (ECD->getType() == BestType) {
13711 // Already the right type!
13712 if (getLangOpts().CPlusPlus)
13713 // C++ [dcl.enum]p4: Following the closing brace of an
13714 // enum-specifier, each enumerator has the type of its
13716 ECD->setType(EnumType);
13720 NewWidth = BestWidth;
13721 NewSign = BestType->isSignedIntegerOrEnumerationType();
13724 // Adjust the APSInt value.
13725 InitVal = InitVal.extOrTrunc(NewWidth);
13726 InitVal.setIsSigned(NewSign);
13727 ECD->setInitVal(InitVal);
13729 // Adjust the Expr initializer and type.
13730 if (ECD->getInitExpr() &&
13731 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType()))
13732 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy,
13734 ECD->getInitExpr(),
13735 /*base paths*/ nullptr,
13737 if (getLangOpts().CPlusPlus)
13738 // C++ [dcl.enum]p4: Following the closing brace of an
13739 // enum-specifier, each enumerator has the type of its
13741 ECD->setType(EnumType);
13743 ECD->setType(NewTy);
13746 Enum->completeDefinition(BestType, BestPromotionType,
13747 NumPositiveBits, NumNegativeBits);
13749 CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType);
13751 // Now that the enum type is defined, ensure it's not been underaligned.
13752 if (Enum->hasAttrs())
13753 CheckAlignasUnderalignment(Enum);
13756 Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr,
13757 SourceLocation StartLoc,
13758 SourceLocation EndLoc) {
13759 StringLiteral *AsmString = cast<StringLiteral>(expr);
13761 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext,
13762 AsmString, StartLoc,
13764 CurContext->addDecl(New);
13768 static void checkModuleImportContext(Sema &S, Module *M,
13769 SourceLocation ImportLoc,
13771 if (auto *LSD = dyn_cast<LinkageSpecDecl>(DC)) {
13772 switch (LSD->getLanguage()) {
13773 case LinkageSpecDecl::lang_c:
13774 if (!M->IsExternC) {
13775 S.Diag(ImportLoc, diag::err_module_import_in_extern_c)
13776 << M->getFullModuleName();
13777 S.Diag(LSD->getLocStart(), diag::note_module_import_in_extern_c);
13781 case LinkageSpecDecl::lang_cxx:
13784 DC = LSD->getParent();
13787 while (isa<LinkageSpecDecl>(DC))
13788 DC = DC->getParent();
13789 if (!isa<TranslationUnitDecl>(DC)) {
13790 S.Diag(ImportLoc, diag::err_module_import_not_at_top_level)
13791 << M->getFullModuleName() << DC;
13792 S.Diag(cast<Decl>(DC)->getLocStart(),
13793 diag::note_module_import_not_at_top_level)
13798 DeclResult Sema::ActOnModuleImport(SourceLocation AtLoc,
13799 SourceLocation ImportLoc,
13800 ModuleIdPath Path) {
13802 getModuleLoader().loadModule(ImportLoc, Path, Module::AllVisible,
13803 /*IsIncludeDirective=*/false);
13807 checkModuleImportContext(*this, Mod, ImportLoc, CurContext);
13809 // FIXME: we should support importing a submodule within a different submodule
13810 // of the same top-level module. Until we do, make it an error rather than
13811 // silently ignoring the import.
13812 if (Mod->getTopLevelModuleName() == getLangOpts().CurrentModule)
13813 Diag(ImportLoc, diag::err_module_self_import)
13814 << Mod->getFullModuleName() << getLangOpts().CurrentModule;
13815 else if (Mod->getTopLevelModuleName() == getLangOpts().ImplementationOfModule)
13816 Diag(ImportLoc, diag::err_module_import_in_implementation)
13817 << Mod->getFullModuleName() << getLangOpts().ImplementationOfModule;
13819 SmallVector<SourceLocation, 2> IdentifierLocs;
13820 Module *ModCheck = Mod;
13821 for (unsigned I = 0, N = Path.size(); I != N; ++I) {
13822 // If we've run out of module parents, just drop the remaining identifiers.
13823 // We need the length to be consistent.
13826 ModCheck = ModCheck->Parent;
13828 IdentifierLocs.push_back(Path[I].second);
13831 ImportDecl *Import = ImportDecl::Create(Context,
13832 Context.getTranslationUnitDecl(),
13833 AtLoc.isValid()? AtLoc : ImportLoc,
13834 Mod, IdentifierLocs);
13835 Context.getTranslationUnitDecl()->addDecl(Import);
13839 void Sema::ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod) {
13840 checkModuleImportContext(*this, Mod, DirectiveLoc, CurContext);
13842 // FIXME: Should we synthesize an ImportDecl here?
13843 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, DirectiveLoc,
13844 /*Complain=*/true);
13847 void Sema::createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
13849 // Bail if we're not allowed to implicitly import a module here.
13850 if (isSFINAEContext() || !getLangOpts().ModulesErrorRecovery)
13853 // Create the implicit import declaration.
13854 TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
13855 ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU,
13857 TU->addDecl(ImportD);
13858 Consumer.HandleImplicitImportDecl(ImportD);
13860 // Make the module visible.
13861 getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, Loc,
13862 /*Complain=*/false);
13865 void Sema::ActOnPragmaRedefineExtname(IdentifierInfo* Name,
13866 IdentifierInfo* AliasName,
13867 SourceLocation PragmaLoc,
13868 SourceLocation NameLoc,
13869 SourceLocation AliasNameLoc) {
13870 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc,
13871 LookupOrdinaryName);
13872 AsmLabelAttr *Attr = ::new (Context) AsmLabelAttr(AliasNameLoc, Context,
13873 AliasName->getName(), 0);
13876 PrevDecl->addAttr(Attr);
13878 (void)ExtnameUndeclaredIdentifiers.insert(
13879 std::pair<IdentifierInfo*,AsmLabelAttr*>(Name, Attr));
13882 void Sema::ActOnPragmaWeakID(IdentifierInfo* Name,
13883 SourceLocation PragmaLoc,
13884 SourceLocation NameLoc) {
13885 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName);
13888 PrevDecl->addAttr(WeakAttr::CreateImplicit(Context, PragmaLoc));
13890 (void)WeakUndeclaredIdentifiers.insert(
13891 std::pair<IdentifierInfo*,WeakInfo>
13892 (Name, WeakInfo((IdentifierInfo*)nullptr, NameLoc)));
13896 void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name,
13897 IdentifierInfo* AliasName,
13898 SourceLocation PragmaLoc,
13899 SourceLocation NameLoc,
13900 SourceLocation AliasNameLoc) {
13901 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc,
13902 LookupOrdinaryName);
13903 WeakInfo W = WeakInfo(Name, NameLoc);
13906 if (!PrevDecl->hasAttr<AliasAttr>())
13907 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl))
13908 DeclApplyPragmaWeak(TUScope, ND, W);
13910 (void)WeakUndeclaredIdentifiers.insert(
13911 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W));
13915 Decl *Sema::getObjCDeclContext() const {
13916 return (dyn_cast_or_null<ObjCContainerDecl>(CurContext));
13919 AvailabilityResult Sema::getCurContextAvailability() const {
13920 const Decl *D = cast<Decl>(getCurObjCLexicalContext());
13921 // If we are within an Objective-C method, we should consult
13922 // both the availability of the method as well as the
13923 // enclosing class. If the class is (say) deprecated,
13924 // the entire method is considered deprecated from the
13925 // purpose of checking if the current context is deprecated.
13926 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
13927 AvailabilityResult R = MD->getAvailability();
13928 if (R != AR_Available)
13930 D = MD->getClassInterface();
13932 // If we are within an Objective-c @implementation, it
13933 // gets the same availability context as the @interface.
13934 else if (const ObjCImplementationDecl *ID =
13935 dyn_cast<ObjCImplementationDecl>(D)) {
13936 D = ID->getClassInterface();
13938 // Recover from user error.
13939 return D ? D->getAvailability() : AR_Available;