//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements semantic analysis for declarations. // //===----------------------------------------------------------------------===// #include "clang/Sema/SemaInternal.h" #include "TypeLocBuilder.h" #include "clang/AST/ASTConsumer.h" #include "clang/AST/ASTContext.h" #include "clang/AST/CXXInheritance.h" #include "clang/AST/CharUnits.h" #include "clang/AST/CommentDiagnostic.h" #include "clang/AST/DeclCXX.h" #include "clang/AST/DeclObjC.h" #include "clang/AST/DeclTemplate.h" #include "clang/AST/EvaluatedExprVisitor.h" #include "clang/AST/ExprCXX.h" #include "clang/AST/StmtCXX.h" #include "clang/Basic/PartialDiagnostic.h" #include "clang/Basic/SourceManager.h" #include "clang/Basic/TargetInfo.h" #include "clang/Lex/HeaderSearch.h" // FIXME: Sema shouldn't depend on Lex #include "clang/Lex/ModuleLoader.h" // FIXME: Sema shouldn't depend on Lex #include "clang/Lex/Preprocessor.h" // FIXME: Sema shouldn't depend on Lex #include "clang/Parse/ParseDiagnostic.h" #include "clang/Sema/CXXFieldCollector.h" #include "clang/Sema/DeclSpec.h" #include "clang/Sema/DelayedDiagnostic.h" #include "clang/Sema/Initialization.h" #include "clang/Sema/Lookup.h" #include "clang/Sema/ParsedTemplate.h" #include "clang/Sema/Scope.h" #include "clang/Sema/ScopeInfo.h" #include "llvm/ADT/SmallString.h" #include "llvm/ADT/Triple.h" #include <algorithm> #include <cstring> #include <functional> using namespace clang; using namespace sema; Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType) { if (OwnedType) { Decl *Group[2] = { OwnedType, Ptr }; return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, 2)); } return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); } namespace { class TypeNameValidatorCCC : public CorrectionCandidateCallback { public: TypeNameValidatorCCC(bool AllowInvalid, bool WantClass=false) : AllowInvalidDecl(AllowInvalid), WantClassName(WantClass) { WantExpressionKeywords = false; WantCXXNamedCasts = false; WantRemainingKeywords = false; } virtual bool ValidateCandidate(const TypoCorrection &candidate) { if (NamedDecl *ND = candidate.getCorrectionDecl()) return (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND)) && (AllowInvalidDecl || !ND->isInvalidDecl()); else return !WantClassName && candidate.isKeyword(); } private: bool AllowInvalidDecl; bool WantClassName; }; } /// \brief Determine whether the token kind starts a simple-type-specifier. bool Sema::isSimpleTypeSpecifier(tok::TokenKind Kind) const { switch (Kind) { // FIXME: Take into account the current language when deciding whether a // token kind is a valid type specifier case tok::kw_short: case tok::kw_long: case tok::kw___int64: case tok::kw___int128: case tok::kw_signed: case tok::kw_unsigned: case tok::kw_void: case tok::kw_char: case tok::kw_int: case tok::kw_half: case tok::kw_float: case tok::kw_double: case tok::kw_wchar_t: case tok::kw_bool: case tok::kw___underlying_type: return true; case tok::annot_typename: case tok::kw_char16_t: case tok::kw_char32_t: case tok::kw_typeof: case tok::kw_decltype: return getLangOpts().CPlusPlus; default: break; } return false; } /// \brief If the identifier refers to a type name within this scope, /// return the declaration of that type. /// /// This routine performs ordinary name lookup of the identifier II /// within the given scope, with optional C++ scope specifier SS, to /// determine whether the name refers to a type. If so, returns an /// opaque pointer (actually a QualType) corresponding to that /// type. Otherwise, returns NULL. /// /// If name lookup results in an ambiguity, this routine will complain /// and then return NULL. ParsedType Sema::getTypeName(const IdentifierInfo &II, SourceLocation NameLoc, Scope *S, CXXScopeSpec *SS, bool isClassName, bool HasTrailingDot, ParsedType ObjectTypePtr, bool IsCtorOrDtorName, bool WantNontrivialTypeSourceInfo, IdentifierInfo **CorrectedII) { // Determine where we will perform name lookup. DeclContext *LookupCtx = 0; if (ObjectTypePtr) { QualType ObjectType = ObjectTypePtr.get(); if (ObjectType->isRecordType()) LookupCtx = computeDeclContext(ObjectType); } else if (SS && SS->isNotEmpty()) { LookupCtx = computeDeclContext(*SS, false); if (!LookupCtx) { if (isDependentScopeSpecifier(*SS)) { // C++ [temp.res]p3: // A qualified-id that refers to a type and in which the // nested-name-specifier depends on a template-parameter (14.6.2) // shall be prefixed by the keyword typename to indicate that the // qualified-id denotes a type, forming an // elaborated-type-specifier (7.1.5.3). // // We therefore do not perform any name lookup if the result would // refer to a member of an unknown specialization. if (!isClassName && !IsCtorOrDtorName) return ParsedType(); // We know from the grammar that this name refers to a type, // so build a dependent node to describe the type. if (WantNontrivialTypeSourceInfo) return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get(); NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context); QualType T = CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc, II, NameLoc); return ParsedType::make(T); } return ParsedType(); } if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS, LookupCtx)) return ParsedType(); } // FIXME: LookupNestedNameSpecifierName isn't the right kind of // lookup for class-names. LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : LookupOrdinaryName; LookupResult Result(*this, &II, NameLoc, Kind); if (LookupCtx) { // Perform "qualified" name lookup into the declaration context we // computed, which is either the type of the base of a member access // expression or the declaration context associated with a prior // nested-name-specifier. LookupQualifiedName(Result, LookupCtx); if (ObjectTypePtr && Result.empty()) { // C++ [basic.lookup.classref]p3: // If the unqualified-id is ~type-name, the type-name is looked up // in the context of the entire postfix-expression. If the type T of // the object expression is of a class type C, the type-name is also // looked up in the scope of class C. At least one of the lookups shall // find a name that refers to (possibly cv-qualified) T. LookupName(Result, S); } } else { // Perform unqualified name lookup. LookupName(Result, S); } NamedDecl *IIDecl = 0; switch (Result.getResultKind()) { case LookupResult::NotFound: case LookupResult::NotFoundInCurrentInstantiation: if (CorrectedII) { TypeNameValidatorCCC Validator(true, isClassName); TypoCorrection Correction = CorrectTypo(Result.getLookupNameInfo(), Kind, S, SS, Validator); IdentifierInfo *NewII = Correction.getCorrectionAsIdentifierInfo(); TemplateTy Template; bool MemberOfUnknownSpecialization; UnqualifiedId TemplateName; TemplateName.setIdentifier(NewII, NameLoc); NestedNameSpecifier *NNS = Correction.getCorrectionSpecifier(); CXXScopeSpec NewSS, *NewSSPtr = SS; if (SS && NNS) { NewSS.MakeTrivial(Context, NNS, SourceRange(NameLoc)); NewSSPtr = &NewSS; } if (Correction && (NNS || NewII != &II) && // Ignore a correction to a template type as the to-be-corrected // identifier is not a template (typo correction for template names // is handled elsewhere). !(getLangOpts().CPlusPlus && NewSSPtr && isTemplateName(S, *NewSSPtr, false, TemplateName, ParsedType(), false, Template, MemberOfUnknownSpecialization))) { ParsedType Ty = getTypeName(*NewII, NameLoc, S, NewSSPtr, isClassName, HasTrailingDot, ObjectTypePtr, IsCtorOrDtorName, WantNontrivialTypeSourceInfo); if (Ty) { std::string CorrectedStr(Correction.getAsString(getLangOpts())); std::string CorrectedQuotedStr( Correction.getQuoted(getLangOpts())); Diag(NameLoc, diag::err_unknown_type_or_class_name_suggest) << Result.getLookupName() << CorrectedQuotedStr << isClassName << FixItHint::CreateReplacement(SourceRange(NameLoc), CorrectedStr); if (NamedDecl *FirstDecl = Correction.getCorrectionDecl()) Diag(FirstDecl->getLocation(), diag::note_previous_decl) << CorrectedQuotedStr; if (SS && NNS) SS->MakeTrivial(Context, NNS, SourceRange(NameLoc)); *CorrectedII = NewII; return Ty; } } } // If typo correction failed or was not performed, fall through case LookupResult::FoundOverloaded: case LookupResult::FoundUnresolvedValue: Result.suppressDiagnostics(); return ParsedType(); case LookupResult::Ambiguous: // Recover from type-hiding ambiguities by hiding the type. We'll // do the lookup again when looking for an object, and we can // diagnose the error then. If we don't do this, then the error // about hiding the type will be immediately followed by an error // that only makes sense if the identifier was treated like a type. if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { Result.suppressDiagnostics(); return ParsedType(); } // Look to see if we have a type anywhere in the list of results. for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); Res != ResEnd; ++Res) { if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { if (!IIDecl || (*Res)->getLocation().getRawEncoding() < IIDecl->getLocation().getRawEncoding()) IIDecl = *Res; } } if (!IIDecl) { // None of the entities we found is a type, so there is no way // to even assume that the result is a type. In this case, don't // complain about the ambiguity. The parser will either try to // perform this lookup again (e.g., as an object name), which // will produce the ambiguity, or will complain that it expected // a type name. Result.suppressDiagnostics(); return ParsedType(); } // We found a type within the ambiguous lookup; diagnose the // ambiguity and then return that type. This might be the right // answer, or it might not be, but it suppresses any attempt to // perform the name lookup again. break; case LookupResult::Found: IIDecl = Result.getFoundDecl(); break; } assert(IIDecl && "Didn't find decl"); QualType T; if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { DiagnoseUseOfDecl(IIDecl, NameLoc); if (T.isNull()) T = Context.getTypeDeclType(TD); // NOTE: avoid constructing an ElaboratedType(Loc) if this is a // constructor or destructor name (in such a case, the scope specifier // will be attached to the enclosing Expr or Decl node). if (SS && SS->isNotEmpty() && !IsCtorOrDtorName) { if (WantNontrivialTypeSourceInfo) { // Construct a type with type-source information. TypeLocBuilder Builder; Builder.pushTypeSpec(T).setNameLoc(NameLoc); T = getElaboratedType(ETK_None, *SS, T); ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); ElabTL.setElaboratedKeywordLoc(SourceLocation()); ElabTL.setQualifierLoc(SS->getWithLocInContext(Context)); return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); } else { T = getElaboratedType(ETK_None, *SS, T); } } } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { (void)DiagnoseUseOfDecl(IDecl, NameLoc); if (!HasTrailingDot) T = Context.getObjCInterfaceType(IDecl); } if (T.isNull()) { // If it's not plausibly a type, suppress diagnostics. Result.suppressDiagnostics(); return ParsedType(); } return ParsedType::make(T); } /// isTagName() - This method is called *for error recovery purposes only* /// to determine if the specified name is a valid tag name ("struct foo"). If /// so, this returns the TST for the tag corresponding to it (TST_enum, /// TST_union, TST_struct, TST_interface, TST_class). This is used to diagnose /// cases in C where the user forgot to specify the tag. DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { // Do a tag name lookup in this scope. LookupResult R(*this, &II, SourceLocation(), LookupTagName); LookupName(R, S, false); R.suppressDiagnostics(); if (R.getResultKind() == LookupResult::Found) if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { switch (TD->getTagKind()) { case TTK_Struct: return DeclSpec::TST_struct; case TTK_Interface: return DeclSpec::TST_interface; case TTK_Union: return DeclSpec::TST_union; case TTK_Class: return DeclSpec::TST_class; case TTK_Enum: return DeclSpec::TST_enum; } } return DeclSpec::TST_unspecified; } /// isMicrosoftMissingTypename - In Microsoft mode, within class scope, /// if a CXXScopeSpec's type is equal to the type of one of the base classes /// then downgrade the missing typename error to a warning. /// This is needed for MSVC compatibility; Example: /// @code /// template<class T> class A { /// public: /// typedef int TYPE; /// }; /// template<class T> class B : public A<T> { /// public: /// A<T>::TYPE a; // no typename required because A<T> is a base class. /// }; /// @endcode bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S) { if (CurContext->isRecord()) { const Type *Ty = SS->getScopeRep()->getAsType(); CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext); for (CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin(), BaseEnd = RD->bases_end(); Base != BaseEnd; ++Base) if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base->getType())) return true; return S->isFunctionPrototypeScope(); } return CurContext->isFunctionOrMethod() || S->isFunctionPrototypeScope(); } bool Sema::DiagnoseUnknownTypeName(IdentifierInfo *&II, SourceLocation IILoc, Scope *S, CXXScopeSpec *SS, ParsedType &SuggestedType) { // We don't have anything to suggest (yet). SuggestedType = ParsedType(); // There may have been a typo in the name of the type. Look up typo // results, in case we have something that we can suggest. TypeNameValidatorCCC Validator(false); if (TypoCorrection Corrected = CorrectTypo(DeclarationNameInfo(II, IILoc), LookupOrdinaryName, S, SS, Validator)) { std::string CorrectedStr(Corrected.getAsString(getLangOpts())); std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts())); if (Corrected.isKeyword()) { // We corrected to a keyword. IdentifierInfo *NewII = Corrected.getCorrectionAsIdentifierInfo(); if (!isSimpleTypeSpecifier(NewII->getTokenID())) CorrectedQuotedStr = "the keyword " + CorrectedQuotedStr; Diag(IILoc, diag::err_unknown_typename_suggest) << II << CorrectedQuotedStr << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), CorrectedStr); II = NewII; } else { NamedDecl *Result = Corrected.getCorrectionDecl(); // We found a similarly-named type or interface; suggest that. if (!SS || !SS->isSet()) { Diag(IILoc, diag::err_unknown_typename_suggest) << II << CorrectedQuotedStr << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), CorrectedStr); } else if (DeclContext *DC = computeDeclContext(*SS, false)) { bool droppedSpecifier = Corrected.WillReplaceSpecifier() && II->getName().equals(CorrectedStr); Diag(IILoc, diag::err_unknown_nested_typename_suggest) << II << DC << droppedSpecifier << CorrectedQuotedStr << SS->getRange() << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), CorrectedStr); } else { llvm_unreachable("could not have corrected a typo here"); } Diag(Result->getLocation(), diag::note_previous_decl) << CorrectedQuotedStr; SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS, false, false, ParsedType(), /*IsCtorOrDtorName=*/false, /*NonTrivialTypeSourceInfo=*/true); } return true; } if (getLangOpts().CPlusPlus) { // See if II is a class template that the user forgot to pass arguments to. UnqualifiedId Name; Name.setIdentifier(II, IILoc); CXXScopeSpec EmptySS; TemplateTy TemplateResult; bool MemberOfUnknownSpecialization; if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, Name, ParsedType(), true, TemplateResult, MemberOfUnknownSpecialization) == TNK_Type_template) { TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); Diag(IILoc, diag::err_template_missing_args) << TplName; if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { Diag(TplDecl->getLocation(), diag::note_template_decl_here) << TplDecl->getTemplateParameters()->getSourceRange(); } return true; } } // FIXME: Should we move the logic that tries to recover from a missing tag // (struct, union, enum) from Parser::ParseImplicitInt here, instead? if (!SS || (!SS->isSet() && !SS->isInvalid())) Diag(IILoc, diag::err_unknown_typename) << II; else if (DeclContext *DC = computeDeclContext(*SS, false)) Diag(IILoc, diag::err_typename_nested_not_found) << II << DC << SS->getRange(); else if (isDependentScopeSpecifier(*SS)) { unsigned DiagID = diag::err_typename_missing; if (getLangOpts().MicrosoftMode && isMicrosoftMissingTypename(SS, S)) DiagID = diag::warn_typename_missing; Diag(SS->getRange().getBegin(), DiagID) << (NestedNameSpecifier *)SS->getScopeRep() << II->getName() << SourceRange(SS->getRange().getBegin(), IILoc) << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, *II, IILoc).get(); } else { assert(SS && SS->isInvalid() && "Invalid scope specifier has already been diagnosed"); } return true; } /// \brief Determine whether the given result set contains either a type name /// or static bool isResultTypeOrTemplate(LookupResult &R, const Token &NextToken) { bool CheckTemplate = R.getSema().getLangOpts().CPlusPlus && NextToken.is(tok::less); for (LookupResult::iterator I = R.begin(), IEnd = R.end(); I != IEnd; ++I) { if (isa<TypeDecl>(*I) || isa<ObjCInterfaceDecl>(*I)) return true; if (CheckTemplate && isa<TemplateDecl>(*I)) return true; } return false; } static bool isTagTypeWithMissingTag(Sema &SemaRef, LookupResult &Result, Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name, SourceLocation NameLoc) { LookupResult R(SemaRef, Name, NameLoc, Sema::LookupTagName); SemaRef.LookupParsedName(R, S, &SS); if (TagDecl *Tag = R.getAsSingle<TagDecl>()) { const char *TagName = 0; const char *FixItTagName = 0; switch (Tag->getTagKind()) { case TTK_Class: TagName = "class"; FixItTagName = "class "; break; case TTK_Enum: TagName = "enum"; FixItTagName = "enum "; break; case TTK_Struct: TagName = "struct"; FixItTagName = "struct "; break; case TTK_Interface: TagName = "__interface"; FixItTagName = "__interface "; break; case TTK_Union: TagName = "union"; FixItTagName = "union "; break; } SemaRef.Diag(NameLoc, diag::err_use_of_tag_name_without_tag) << Name << TagName << SemaRef.getLangOpts().CPlusPlus << FixItHint::CreateInsertion(NameLoc, FixItTagName); for (LookupResult::iterator I = Result.begin(), IEnd = Result.end(); I != IEnd; ++I) SemaRef.Diag((*I)->getLocation(), diag::note_decl_hiding_tag_type) << Name << TagName; // Replace lookup results with just the tag decl. Result.clear(Sema::LookupTagName); SemaRef.LookupParsedName(Result, S, &SS); return true; } return false; } /// Build a ParsedType for a simple-type-specifier with a nested-name-specifier. static ParsedType buildNestedType(Sema &S, CXXScopeSpec &SS, QualType T, SourceLocation NameLoc) { ASTContext &Context = S.Context; TypeLocBuilder Builder; Builder.pushTypeSpec(T).setNameLoc(NameLoc); T = S.getElaboratedType(ETK_None, SS, T); ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); ElabTL.setElaboratedKeywordLoc(SourceLocation()); ElabTL.setQualifierLoc(SS.getWithLocInContext(Context)); return S.CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); } Sema::NameClassification Sema::ClassifyName(Scope *S, CXXScopeSpec &SS, IdentifierInfo *&Name, SourceLocation NameLoc, const Token &NextToken, bool IsAddressOfOperand, CorrectionCandidateCallback *CCC) { DeclarationNameInfo NameInfo(Name, NameLoc); ObjCMethodDecl *CurMethod = getCurMethodDecl(); if (NextToken.is(tok::coloncolon)) { BuildCXXNestedNameSpecifier(S, *Name, NameLoc, NextToken.getLocation(), QualType(), false, SS, 0, false); } LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName); LookupParsedName(Result, S, &SS, !CurMethod); // Perform lookup for Objective-C instance variables (including automatically // synthesized instance variables), if we're in an Objective-C method. // FIXME: This lookup really, really needs to be folded in to the normal // unqualified lookup mechanism. if (!SS.isSet() && CurMethod && !isResultTypeOrTemplate(Result, NextToken)) { ExprResult E = LookupInObjCMethod(Result, S, Name, true); if (E.get() || E.isInvalid()) return E; } bool SecondTry = false; bool IsFilteredTemplateName = false; Corrected: switch (Result.getResultKind()) { case LookupResult::NotFound: // If an unqualified-id is followed by a '(', then we have a function // call. if (!SS.isSet() && NextToken.is(tok::l_paren)) { // In C++, this is an ADL-only call. // FIXME: Reference? if (getLangOpts().CPlusPlus) return BuildDeclarationNameExpr(SS, Result, /*ADL=*/true); // C90 6.3.2.2: // If the expression that precedes the parenthesized argument list in a // function call consists solely of an identifier, and if no // declaration is visible for this identifier, the identifier is // implicitly declared exactly as if, in the innermost block containing // the function call, the declaration // // extern int identifier (); // // appeared. // // We also allow this in C99 as an extension. if (NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *Name, S)) { Result.addDecl(D); Result.resolveKind(); return BuildDeclarationNameExpr(SS, Result, /*ADL=*/false); } } // In C, we first see whether there is a tag type by the same name, in // which case it's likely that the user just forget to write "enum", // "struct", or "union". if (!getLangOpts().CPlusPlus && !SecondTry && isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) { break; } // Perform typo correction to determine if there is another name that is // close to this name. if (!SecondTry && CCC) { SecondTry = true; if (TypoCorrection Corrected = CorrectTypo(Result.getLookupNameInfo(), Result.getLookupKind(), S, &SS, *CCC)) { unsigned UnqualifiedDiag = diag::err_undeclared_var_use_suggest; unsigned QualifiedDiag = diag::err_no_member_suggest; std::string CorrectedStr(Corrected.getAsString(getLangOpts())); std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts())); NamedDecl *FirstDecl = Corrected.getCorrectionDecl(); NamedDecl *UnderlyingFirstDecl = FirstDecl? FirstDecl->getUnderlyingDecl() : 0; if (getLangOpts().CPlusPlus && NextToken.is(tok::less) && UnderlyingFirstDecl && isa<TemplateDecl>(UnderlyingFirstDecl)) { UnqualifiedDiag = diag::err_no_template_suggest; QualifiedDiag = diag::err_no_member_template_suggest; } else if (UnderlyingFirstDecl && (isa<TypeDecl>(UnderlyingFirstDecl) || isa<ObjCInterfaceDecl>(UnderlyingFirstDecl) || isa<ObjCCompatibleAliasDecl>(UnderlyingFirstDecl))) { UnqualifiedDiag = diag::err_unknown_typename_suggest; QualifiedDiag = diag::err_unknown_nested_typename_suggest; } if (SS.isEmpty()) { Diag(NameLoc, UnqualifiedDiag) << Name << CorrectedQuotedStr << FixItHint::CreateReplacement(NameLoc, CorrectedStr); } else {// FIXME: is this even reachable? Test it. bool droppedSpecifier = Corrected.WillReplaceSpecifier() && Name->getName().equals(CorrectedStr); Diag(NameLoc, QualifiedDiag) << Name << computeDeclContext(SS, false) << droppedSpecifier << CorrectedQuotedStr << SS.getRange() << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), CorrectedStr); } // Update the name, so that the caller has the new name. Name = Corrected.getCorrectionAsIdentifierInfo(); // Typo correction corrected to a keyword. if (Corrected.isKeyword()) return Corrected.getCorrectionAsIdentifierInfo(); // Also update the LookupResult... // FIXME: This should probably go away at some point Result.clear(); Result.setLookupName(Corrected.getCorrection()); if (FirstDecl) { Result.addDecl(FirstDecl); Diag(FirstDecl->getLocation(), diag::note_previous_decl) << CorrectedQuotedStr; } // If we found an Objective-C instance variable, let // LookupInObjCMethod build the appropriate expression to // reference the ivar. // FIXME: This is a gross hack. if (ObjCIvarDecl *Ivar = Result.getAsSingle<ObjCIvarDecl>()) { Result.clear(); ExprResult E(LookupInObjCMethod(Result, S, Ivar->getIdentifier())); return E; } goto Corrected; } } // We failed to correct; just fall through and let the parser deal with it. Result.suppressDiagnostics(); return NameClassification::Unknown(); case LookupResult::NotFoundInCurrentInstantiation: { // We performed name lookup into the current instantiation, and there were // dependent bases, so we treat this result the same way as any other // dependent nested-name-specifier. // C++ [temp.res]p2: // A name used in a template declaration or definition and that is // dependent on a template-parameter is assumed not to name a type // unless the applicable name lookup finds a type name or the name is // qualified by the keyword typename. // // FIXME: If the next token is '<', we might want to ask the parser to // perform some heroics to see if we actually have a // template-argument-list, which would indicate a missing 'template' // keyword here. return ActOnDependentIdExpression(SS, /*TemplateKWLoc=*/SourceLocation(), NameInfo, IsAddressOfOperand, /*TemplateArgs=*/0); } case LookupResult::Found: case LookupResult::FoundOverloaded: case LookupResult::FoundUnresolvedValue: break; case LookupResult::Ambiguous: if (getLangOpts().CPlusPlus && NextToken.is(tok::less) && hasAnyAcceptableTemplateNames(Result)) { // C++ [temp.local]p3: // A lookup that finds an injected-class-name (10.2) can result in an // ambiguity in certain cases (for example, if it is found in more than // one base class). If all of the injected-class-names that are found // refer to specializations of the same class template, and if the name // is followed by a template-argument-list, the reference refers to the // class template itself and not a specialization thereof, and is not // ambiguous. // // This filtering can make an ambiguous result into an unambiguous one, // so try again after filtering out template names. FilterAcceptableTemplateNames(Result); if (!Result.isAmbiguous()) { IsFilteredTemplateName = true; break; } } // Diagnose the ambiguity and return an error. return NameClassification::Error(); } if (getLangOpts().CPlusPlus && NextToken.is(tok::less) && (IsFilteredTemplateName || hasAnyAcceptableTemplateNames(Result))) { // C++ [temp.names]p3: // After name lookup (3.4) finds that a name is a template-name or that // an operator-function-id or a literal- operator-id refers to a set of // overloaded functions any member of which is a function template if // this is followed by a <, the < is always taken as the delimiter of a // template-argument-list and never as the less-than operator. if (!IsFilteredTemplateName) FilterAcceptableTemplateNames(Result); if (!Result.empty()) { bool IsFunctionTemplate; bool IsVarTemplate; TemplateName Template; if (Result.end() - Result.begin() > 1) { IsFunctionTemplate = true; Template = Context.getOverloadedTemplateName(Result.begin(), Result.end()); } else { TemplateDecl *TD = cast<TemplateDecl>((*Result.begin())->getUnderlyingDecl()); IsFunctionTemplate = isa<FunctionTemplateDecl>(TD); IsVarTemplate = isa<VarTemplateDecl>(TD); if (SS.isSet() && !SS.isInvalid()) Template = Context.getQualifiedTemplateName(SS.getScopeRep(), /*TemplateKeyword=*/false, TD); else Template = TemplateName(TD); } if (IsFunctionTemplate) { // Function templates always go through overload resolution, at which // point we'll perform the various checks (e.g., accessibility) we need // to based on which function we selected. Result.suppressDiagnostics(); return NameClassification::FunctionTemplate(Template); } return IsVarTemplate ? NameClassification::VarTemplate(Template) : NameClassification::TypeTemplate(Template); } } NamedDecl *FirstDecl = (*Result.begin())->getUnderlyingDecl(); if (TypeDecl *Type = dyn_cast<TypeDecl>(FirstDecl)) { DiagnoseUseOfDecl(Type, NameLoc); QualType T = Context.getTypeDeclType(Type); if (SS.isNotEmpty()) return buildNestedType(*this, SS, T, NameLoc); return ParsedType::make(T); } ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(FirstDecl); if (!Class) { // FIXME: It's unfortunate that we don't have a Type node for handling this. if (ObjCCompatibleAliasDecl *Alias = dyn_cast<ObjCCompatibleAliasDecl>(FirstDecl)) Class = Alias->getClassInterface(); } if (Class) { DiagnoseUseOfDecl(Class, NameLoc); if (NextToken.is(tok::period)) { // Interface. <something> is parsed as a property reference expression. // Just return "unknown" as a fall-through for now. Result.suppressDiagnostics(); return NameClassification::Unknown(); } QualType T = Context.getObjCInterfaceType(Class); return ParsedType::make(T); } // We can have a type template here if we're classifying a template argument. if (isa<TemplateDecl>(FirstDecl) && !isa<FunctionTemplateDecl>(FirstDecl)) return NameClassification::TypeTemplate( TemplateName(cast<TemplateDecl>(FirstDecl))); // Check for a tag type hidden by a non-type decl in a few cases where it // seems likely a type is wanted instead of the non-type that was found. bool NextIsOp = NextToken.is(tok::amp) || NextToken.is(tok::star); if ((NextToken.is(tok::identifier) || (NextIsOp && FirstDecl->isFunctionOrFunctionTemplate())) && isTagTypeWithMissingTag(*this, Result, S, SS, Name, NameLoc)) { TypeDecl *Type = Result.getAsSingle<TypeDecl>(); DiagnoseUseOfDecl(Type, NameLoc); QualType T = Context.getTypeDeclType(Type); if (SS.isNotEmpty()) return buildNestedType(*this, SS, T, NameLoc); return ParsedType::make(T); } if (FirstDecl->isCXXClassMember()) return BuildPossibleImplicitMemberExpr(SS, SourceLocation(), Result, 0); bool ADL = UseArgumentDependentLookup(SS, Result, NextToken.is(tok::l_paren)); return BuildDeclarationNameExpr(SS, Result, ADL); } // Determines the context to return to after temporarily entering a // context. This depends in an unnecessarily complicated way on the // exact ordering of callbacks from the parser. DeclContext *Sema::getContainingDC(DeclContext *DC) { // Functions defined inline within classes aren't parsed until we've // finished parsing the top-level class, so the top-level class is // the context we'll need to return to. if (isa<FunctionDecl>(DC)) { DC = DC->getLexicalParent(); // A function not defined within a class will always return to its // lexical context. if (!isa<CXXRecordDecl>(DC)) return DC; // A C++ inline method/friend is parsed *after* the topmost class // it was declared in is fully parsed ("complete"); the topmost // class is the context we need to return to. while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) DC = RD; // Return the declaration context of the topmost class the inline method is // declared in. return DC; } return DC->getLexicalParent(); } void Sema::PushDeclContext(Scope *S, DeclContext *DC) { assert(getContainingDC(DC) == CurContext && "The next DeclContext should be lexically contained in the current one."); CurContext = DC; S->setEntity(DC); } void Sema::PopDeclContext() { assert(CurContext && "DeclContext imbalance!"); CurContext = getContainingDC(CurContext); assert(CurContext && "Popped translation unit!"); } /// EnterDeclaratorContext - Used when we must lookup names in the context /// of a declarator's nested name specifier. /// void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { // C++0x [basic.lookup.unqual]p13: // A name used in the definition of a static data member of class // X (after the qualified-id of the static member) is looked up as // if the name was used in a member function of X. // C++0x [basic.lookup.unqual]p14: // If a variable member of a namespace is defined outside of the // scope of its namespace then any name used in the definition of // the variable member (after the declarator-id) is looked up as // if the definition of the variable member occurred in its // namespace. // Both of these imply that we should push a scope whose context // is the semantic context of the declaration. We can't use // PushDeclContext here because that context is not necessarily // lexically contained in the current context. Fortunately, // the containing scope should have the appropriate information. assert(!S->getEntity() && "scope already has entity"); #ifndef NDEBUG Scope *Ancestor = S->getParent(); while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); #endif CurContext = DC; S->setEntity(DC); } void Sema::ExitDeclaratorContext(Scope *S) { assert(S->getEntity() == CurContext && "Context imbalance!"); // Switch back to the lexical context. The safety of this is // enforced by an assert in EnterDeclaratorContext. Scope *Ancestor = S->getParent(); while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); CurContext = (DeclContext*) Ancestor->getEntity(); // We don't need to do anything with the scope, which is going to // disappear. } void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) { FunctionDecl *FD = dyn_cast<FunctionDecl>(D); if (FunctionTemplateDecl *TFD = dyn_cast_or_null<FunctionTemplateDecl>(D)) { // We assume that the caller has already called // ActOnReenterTemplateScope FD = TFD->getTemplatedDecl(); } if (!FD) return; // Same implementation as PushDeclContext, but enters the context // from the lexical parent, rather than the top-level class. assert(CurContext == FD->getLexicalParent() && "The next DeclContext should be lexically contained in the current one."); CurContext = FD; S->setEntity(CurContext); for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) { ParmVarDecl *Param = FD->getParamDecl(P); // If the parameter has an identifier, then add it to the scope if (Param->getIdentifier()) { S->AddDecl(Param); IdResolver.AddDecl(Param); } } } void Sema::ActOnExitFunctionContext() { // Same implementation as PopDeclContext, but returns to the lexical parent, // rather than the top-level class. assert(CurContext && "DeclContext imbalance!"); CurContext = CurContext->getLexicalParent(); assert(CurContext && "Popped translation unit!"); } /// \brief Determine whether we allow overloading of the function /// PrevDecl with another declaration. /// /// This routine determines whether overloading is possible, not /// whether some new function is actually an overload. It will return /// true in C++ (where we can always provide overloads) or, as an /// extension, in C when the previous function is already an /// overloaded function declaration or has the "overloadable" /// attribute. static bool AllowOverloadingOfFunction(LookupResult &Previous, ASTContext &Context) { if (Context.getLangOpts().CPlusPlus) return true; if (Previous.getResultKind() == LookupResult::FoundOverloaded) return true; return (Previous.getResultKind() == LookupResult::Found && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); } /// Add this decl to the scope shadowed decl chains. void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { // Move up the scope chain until we find the nearest enclosing // non-transparent context. The declaration will be introduced into this // scope. while (S->getEntity() && ((DeclContext *)S->getEntity())->isTransparentContext()) S = S->getParent(); // Add scoped declarations into their context, so that they can be // found later. Declarations without a context won't be inserted // into any context. if (AddToContext) CurContext->addDecl(D); // Out-of-line definitions shouldn't be pushed into scope in C++. // Out-of-line variable and function definitions shouldn't even in C. if ((getLangOpts().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && D->isOutOfLine() && !D->getDeclContext()->getRedeclContext()->Equals( D->getLexicalDeclContext()->getRedeclContext())) return; // Template instantiations should also not be pushed into scope. if (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) return; // If this replaces anything in the current scope, IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); for (; I != IEnd; ++I) { if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { S->RemoveDecl(*I); IdResolver.RemoveDecl(*I); // Should only need to replace one decl. break; } } S->AddDecl(D); if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) { // Implicitly-generated labels may end up getting generated in an order that // isn't strictly lexical, which breaks name lookup. Be careful to insert // the label at the appropriate place in the identifier chain. for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) { DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext(); if (IDC == CurContext) { if (!S->isDeclScope(*I)) continue; } else if (IDC->Encloses(CurContext)) break; } IdResolver.InsertDeclAfter(I, D); } else { IdResolver.AddDecl(D); } } void Sema::pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name) { if (IdResolver.tryAddTopLevelDecl(D, Name) && TUScope) TUScope->AddDecl(D); } bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S, bool ExplicitInstantiationOrSpecialization) { return IdResolver.isDeclInScope(D, Ctx, S, ExplicitInstantiationOrSpecialization); } Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { DeclContext *TargetDC = DC->getPrimaryContext(); do { if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) if (ScopeDC->getPrimaryContext() == TargetDC) return S; } while ((S = S->getParent())); return 0; } static bool isOutOfScopePreviousDeclaration(NamedDecl *, DeclContext*, ASTContext&); /// Filters out lookup results that don't fall within the given scope /// as determined by isDeclInScope. void Sema::FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S, bool ConsiderLinkage, bool ExplicitInstantiationOrSpecialization) { LookupResult::Filter F = R.makeFilter(); while (F.hasNext()) { NamedDecl *D = F.next(); if (isDeclInScope(D, Ctx, S, ExplicitInstantiationOrSpecialization)) continue; if (ConsiderLinkage && isOutOfScopePreviousDeclaration(D, Ctx, Context)) continue; F.erase(); } F.done(); } static bool isUsingDecl(NamedDecl *D) { return isa<UsingShadowDecl>(D) || isa<UnresolvedUsingTypenameDecl>(D) || isa<UnresolvedUsingValueDecl>(D); } /// Removes using shadow declarations from the lookup results. static void RemoveUsingDecls(LookupResult &R) { LookupResult::Filter F = R.makeFilter(); while (F.hasNext()) if (isUsingDecl(F.next())) F.erase(); F.done(); } /// \brief Check for this common pattern: /// @code /// class S { /// S(const S&); // DO NOT IMPLEMENT /// void operator=(const S&); // DO NOT IMPLEMENT /// }; /// @endcode static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { // FIXME: Should check for private access too but access is set after we get // the decl here. if (D->doesThisDeclarationHaveABody()) return false; if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) return CD->isCopyConstructor(); if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) return Method->isCopyAssignmentOperator(); return false; } // We need this to handle // // typedef struct { // void *foo() { return 0; } // } A; // // When we see foo we don't know if after the typedef we will get 'A' or '*A' // for example. If 'A', foo will have external linkage. If we have '*A', // foo will have no linkage. Since we can't know untill we get to the end // of the typedef, this function finds out if D might have non external linkage. // Callers should verify at the end of the TU if it D has external linkage or // not. bool Sema::mightHaveNonExternalLinkage(const DeclaratorDecl *D) { const DeclContext *DC = D->getDeclContext(); while (!DC->isTranslationUnit()) { if (const RecordDecl *RD = dyn_cast<RecordDecl>(DC)){ if (!RD->hasNameForLinkage()) return true; } DC = DC->getParent(); } return !D->isExternallyVisible(); } bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { assert(D); if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) return false; // Ignore class templates. if (D->getDeclContext()->isDependentContext() || D->getLexicalDeclContext()->isDependentContext()) return false; if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) return false; if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) return false; } else { // 'static inline' functions are used in headers; don't warn. // Make sure we get the storage class from the canonical declaration, // since otherwise we will get spurious warnings on specialized // static template functions. if (FD->getCanonicalDecl()->getStorageClass() == SC_Static && FD->isInlineSpecified()) return false; } if (FD->doesThisDeclarationHaveABody() && Context.DeclMustBeEmitted(FD)) return false; } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { // Don't warn on variables of const-qualified or reference type, since their // values can be used even if though they're not odr-used, and because const // qualified variables can appear in headers in contexts where they're not // intended to be used. // FIXME: Use more principled rules for these exemptions. if (!VD->isFileVarDecl() || VD->getType().isConstQualified() || VD->getType()->isReferenceType() || Context.DeclMustBeEmitted(VD)) return false; if (VD->isStaticDataMember() && VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) return false; } else { return false; } // Only warn for unused decls internal to the translation unit. return mightHaveNonExternalLinkage(D); } void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { if (!D) return; if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { const FunctionDecl *First = FD->getFirstDeclaration(); if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) return; // First should already be in the vector. } if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { const VarDecl *First = VD->getFirstDeclaration(); if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) return; // First should already be in the vector. } if (ShouldWarnIfUnusedFileScopedDecl(D)) UnusedFileScopedDecls.push_back(D); } static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { if (D->isInvalidDecl()) return false; if (D->isReferenced() || D->isUsed() || D->hasAttr<UnusedAttr>()) return false; if (isa<LabelDecl>(D)) return true; // White-list anything that isn't a local variable. if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || !D->getDeclContext()->isFunctionOrMethod()) return false; // Types of valid local variables should be complete, so this should succeed. if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { // White-list anything with an __attribute__((unused)) type. QualType Ty = VD->getType(); // Only look at the outermost level of typedef. if (const TypedefType *TT = Ty->getAs<TypedefType>()) { if (TT->getDecl()->hasAttr<UnusedAttr>()) return false; } // If we failed to complete the type for some reason, or if the type is // dependent, don't diagnose the variable. if (Ty->isIncompleteType() || Ty->isDependentType()) return false; if (const TagType *TT = Ty->getAs<TagType>()) { const TagDecl *Tag = TT->getDecl(); if (Tag->hasAttr<UnusedAttr>()) return false; if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { if (!RD->hasTrivialDestructor() && !RD->hasAttr<WarnUnusedAttr>()) return false; if (const Expr *Init = VD->getInit()) { if (const ExprWithCleanups *Cleanups = dyn_cast<ExprWithCleanups>(Init)) Init = Cleanups->getSubExpr(); const CXXConstructExpr *Construct = dyn_cast<CXXConstructExpr>(Init); if (Construct && !Construct->isElidable()) { CXXConstructorDecl *CD = Construct->getConstructor(); if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>()) return false; } } } } // TODO: __attribute__((unused)) templates? } return true; } static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx, FixItHint &Hint) { if (isa<LabelDecl>(D)) { SourceLocation AfterColon = Lexer::findLocationAfterToken(D->getLocEnd(), tok::colon, Ctx.getSourceManager(), Ctx.getLangOpts(), true); if (AfterColon.isInvalid()) return; Hint = FixItHint::CreateRemoval(CharSourceRange:: getCharRange(D->getLocStart(), AfterColon)); } return; } /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used /// unless they are marked attr(unused). void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { FixItHint Hint; if (!ShouldDiagnoseUnusedDecl(D)) return; GenerateFixForUnusedDecl(D, Context, Hint); unsigned DiagID; if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) DiagID = diag::warn_unused_exception_param; else if (isa<LabelDecl>(D)) DiagID = diag::warn_unused_label; else DiagID = diag::warn_unused_variable; Diag(D->getLocation(), DiagID) << D->getDeclName() << Hint; } static void CheckPoppedLabel(LabelDecl *L, Sema &S) { // Verify that we have no forward references left. If so, there was a goto // or address of a label taken, but no definition of it. Label fwd // definitions are indicated with a null substmt. if (L->getStmt() == 0) S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName(); } void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { if (S->decl_empty()) return; assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && "Scope shouldn't contain decls!"); for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); I != E; ++I) { Decl *TmpD = (*I); assert(TmpD && "This decl didn't get pushed??"); assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); NamedDecl *D = cast<NamedDecl>(TmpD); if (!D->getDeclName()) continue; // Diagnose unused variables in this scope. if (!S->hasUnrecoverableErrorOccurred()) DiagnoseUnusedDecl(D); // If this was a forward reference to a label, verify it was defined. if (LabelDecl *LD = dyn_cast<LabelDecl>(D)) CheckPoppedLabel(LD, *this); // Remove this name from our lexical scope. IdResolver.RemoveDecl(D); } } void Sema::ActOnStartFunctionDeclarator() { ++InFunctionDeclarator; } void Sema::ActOnEndFunctionDeclarator() { assert(InFunctionDeclarator); --InFunctionDeclarator; } /// \brief Look for an Objective-C class in the translation unit. /// /// \param Id The name of the Objective-C class we're looking for. If /// typo-correction fixes this name, the Id will be updated /// to the fixed name. /// /// \param IdLoc The location of the name in the translation unit. /// /// \param DoTypoCorrection If true, this routine will attempt typo correction /// if there is no class with the given name. /// /// \returns The declaration of the named Objective-C class, or NULL if the /// class could not be found. ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, SourceLocation IdLoc, bool DoTypoCorrection) { // The third "scope" argument is 0 since we aren't enabling lazy built-in // creation from this context. NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); if (!IDecl && DoTypoCorrection) { // Perform typo correction at the given location, but only if we // find an Objective-C class name. DeclFilterCCC<ObjCInterfaceDecl> Validator; if (TypoCorrection C = CorrectTypo(DeclarationNameInfo(Id, IdLoc), LookupOrdinaryName, TUScope, NULL, Validator)) { IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>(); Diag(IdLoc, diag::err_undef_interface_suggest) << Id << IDecl->getDeclName() << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); Diag(IDecl->getLocation(), diag::note_previous_decl) << IDecl->getDeclName(); Id = IDecl->getIdentifier(); } } ObjCInterfaceDecl *Def = dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); // This routine must always return a class definition, if any. if (Def && Def->getDefinition()) Def = Def->getDefinition(); return Def; } /// getNonFieldDeclScope - Retrieves the innermost scope, starting /// from S, where a non-field would be declared. This routine copes /// with the difference between C and C++ scoping rules in structs and /// unions. For example, the following code is well-formed in C but /// ill-formed in C++: /// @code /// struct S6 { /// enum { BAR } e; /// }; /// /// void test_S6() { /// struct S6 a; /// a.e = BAR; /// } /// @endcode /// For the declaration of BAR, this routine will return a different /// scope. The scope S will be the scope of the unnamed enumeration /// within S6. In C++, this routine will return the scope associated /// with S6, because the enumeration's scope is a transparent /// context but structures can contain non-field names. In C, this /// routine will return the translation unit scope, since the /// enumeration's scope is a transparent context and structures cannot /// contain non-field names. Scope *Sema::getNonFieldDeclScope(Scope *S) { while (((S->getFlags() & Scope::DeclScope) == 0) || (S->getEntity() && ((DeclContext *)S->getEntity())->isTransparentContext()) || (S->isClassScope() && !getLangOpts().CPlusPlus)) S = S->getParent(); return S; } /// \brief Looks up the declaration of "struct objc_super" and /// saves it for later use in building builtin declaration of /// objc_msgSendSuper and objc_msgSendSuper_stret. If no such /// pre-existing declaration exists no action takes place. static void LookupPredefedObjCSuperType(Sema &ThisSema, Scope *S, IdentifierInfo *II) { if (!II->isStr("objc_msgSendSuper")) return; ASTContext &Context = ThisSema.Context; LookupResult Result(ThisSema, &Context.Idents.get("objc_super"), SourceLocation(), Sema::LookupTagName); ThisSema.LookupName(Result, S); if (Result.getResultKind() == LookupResult::Found) if (const TagDecl *TD = Result.getAsSingle<TagDecl>()) Context.setObjCSuperType(Context.getTagDeclType(TD)); } /// LazilyCreateBuiltin - The specified Builtin-ID was first used at /// file scope. lazily create a decl for it. ForRedeclaration is true /// if we're creating this built-in in anticipation of redeclaring the /// built-in. NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, Scope *S, bool ForRedeclaration, SourceLocation Loc) { LookupPredefedObjCSuperType(*this, S, II); Builtin::ID BID = (Builtin::ID)bid; ASTContext::GetBuiltinTypeError Error; QualType R = Context.GetBuiltinType(BID, Error); switch (Error) { case ASTContext::GE_None: // Okay break; case ASTContext::GE_Missing_stdio: if (ForRedeclaration) Diag(Loc, diag::warn_implicit_decl_requires_stdio) << Context.BuiltinInfo.GetName(BID); return 0; case ASTContext::GE_Missing_setjmp: if (ForRedeclaration) Diag(Loc, diag::warn_implicit_decl_requires_setjmp) << Context.BuiltinInfo.GetName(BID); return 0; case ASTContext::GE_Missing_ucontext: if (ForRedeclaration) Diag(Loc, diag::warn_implicit_decl_requires_ucontext) << Context.BuiltinInfo.GetName(BID); return 0; } if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { Diag(Loc, diag::ext_implicit_lib_function_decl) << Context.BuiltinInfo.GetName(BID) << R; if (Context.BuiltinInfo.getHeaderName(BID) && Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl, Loc) != DiagnosticsEngine::Ignored) Diag(Loc, diag::note_please_include_header) << Context.BuiltinInfo.getHeaderName(BID) << Context.BuiltinInfo.GetName(BID); } FunctionDecl *New = FunctionDecl::Create(Context, Context.getTranslationUnitDecl(), Loc, Loc, II, R, /*TInfo=*/0, SC_Extern, false, /*hasPrototype=*/true); New->setImplicit(); // Create Decl objects for each parameter, adding them to the // FunctionDecl. if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { SmallVector<ParmVarDecl*, 16> Params; for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) { ParmVarDecl *parm = ParmVarDecl::Create(Context, New, SourceLocation(), SourceLocation(), 0, FT->getArgType(i), /*TInfo=*/0, SC_None, 0); parm->setScopeInfo(0, i); Params.push_back(parm); } New->setParams(Params); } AddKnownFunctionAttributes(New); // TUScope is the translation-unit scope to insert this function into. // FIXME: This is hideous. We need to teach PushOnScopeChains to // relate Scopes to DeclContexts, and probably eliminate CurContext // entirely, but we're not there yet. DeclContext *SavedContext = CurContext; CurContext = Context.getTranslationUnitDecl(); PushOnScopeChains(New, TUScope); CurContext = SavedContext; return New; } /// \brief Filter out any previous declarations that the given declaration /// should not consider because they are not permitted to conflict, e.g., /// because they come from hidden sub-modules and do not refer to the same /// entity. static void filterNonConflictingPreviousDecls(ASTContext &context, NamedDecl *decl, LookupResult &previous){ // This is only interesting when modules are enabled. if (!context.getLangOpts().Modules) return; // Empty sets are uninteresting. if (previous.empty()) return; LookupResult::Filter filter = previous.makeFilter(); while (filter.hasNext()) { NamedDecl *old = filter.next(); // Non-hidden declarations are never ignored. if (!old->isHidden()) continue; if (!old->isExternallyVisible()) filter.erase(); } filter.done(); } bool Sema::isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New) { QualType OldType; if (TypedefNameDecl *OldTypedef = dyn_cast<TypedefNameDecl>(Old)) OldType = OldTypedef->getUnderlyingType(); else OldType = Context.getTypeDeclType(Old); QualType NewType = New->getUnderlyingType(); if (NewType->isVariablyModifiedType()) { // Must not redefine a typedef with a variably-modified type. int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0; Diag(New->getLocation(), diag::err_redefinition_variably_modified_typedef) << Kind << NewType; if (Old->getLocation().isValid()) Diag(Old->getLocation(), diag::note_previous_definition); New->setInvalidDecl(); return true; } if (OldType != NewType && !OldType->isDependentType() && !NewType->isDependentType() && !Context.hasSameType(OldType, NewType)) { int Kind = isa<TypeAliasDecl>(Old) ? 1 : 0; Diag(New->getLocation(), diag::err_redefinition_different_typedef) << Kind << NewType << OldType; if (Old->getLocation().isValid()) Diag(Old->getLocation(), diag::note_previous_definition); New->setInvalidDecl(); return true; } return false; } /// MergeTypedefNameDecl - We just parsed a typedef 'New' which has the /// same name and scope as a previous declaration 'Old'. Figure out /// how to resolve this situation, merging decls or emitting /// diagnostics as appropriate. If there was an error, set New to be invalid. /// void Sema::MergeTypedefNameDecl(TypedefNameDecl *New, LookupResult &OldDecls) { // If the new decl is known invalid already, don't bother doing any // merging checks. if (New->isInvalidDecl()) return; // Allow multiple definitions for ObjC built-in typedefs. // FIXME: Verify the underlying types are equivalent! if (getLangOpts().ObjC1) { const IdentifierInfo *TypeID = New->getIdentifier(); switch (TypeID->getLength()) { default: break; case 2: { if (!TypeID->isStr("id")) break; QualType T = New->getUnderlyingType(); if (!T->isPointerType()) break; if (!T->isVoidPointerType()) { QualType PT = T->getAs<PointerType>()->getPointeeType(); if (!PT->isStructureType()) break; } Context.setObjCIdRedefinitionType(T); // Install the built-in type for 'id', ignoring the current definition. New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); return; } case 5: if (!TypeID->isStr("Class")) break; Context.setObjCClassRedefinitionType(New->getUnderlyingType()); // Install the built-in type for 'Class', ignoring the current definition. New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); return; case 3: if (!TypeID->isStr("SEL")) break; Context.setObjCSelRedefinitionType(New->getUnderlyingType()); // Install the built-in type for 'SEL', ignoring the current definition. New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); return; } // Fall through - the typedef name was not a builtin type. } // Verify the old decl was also a type. TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); if (!Old) { Diag(New->getLocation(), diag::err_redefinition_different_kind) << New->getDeclName(); NamedDecl *OldD = OldDecls.getRepresentativeDecl(); if (OldD->getLocation().isValid()) Diag(OldD->getLocation(), diag::note_previous_definition); return New->setInvalidDecl(); } // If the old declaration is invalid, just give up here. if (Old->isInvalidDecl()) return New->setInvalidDecl(); // If the typedef types are not identical, reject them in all languages and // with any extensions enabled. if (isIncompatibleTypedef(Old, New)) return; // The types match. Link up the redeclaration chain if the old // declaration was a typedef. if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) New->setPreviousDeclaration(Typedef); mergeDeclAttributes(New, Old); if (getLangOpts().MicrosoftExt) return; if (getLangOpts().CPlusPlus) { // C++ [dcl.typedef]p2: // In a given non-class scope, a typedef specifier can be used to // redefine the name of any type declared in that scope to refer // to the type to which it already refers. if (!isa<CXXRecordDecl>(CurContext)) return; // C++0x [dcl.typedef]p4: // In a given class scope, a typedef specifier can be used to redefine // any class-name declared in that scope that is not also a typedef-name // to refer to the type to which it already refers. // // This wording came in via DR424, which was a correction to the // wording in DR56, which accidentally banned code like: // // struct S { // typedef struct A { } A; // }; // // in the C++03 standard. We implement the C++0x semantics, which // allow the above but disallow // // struct S { // typedef int I; // typedef int I; // }; // // since that was the intent of DR56. if (!isa<TypedefNameDecl>(Old)) return; Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_definition); return New->setInvalidDecl(); } // Modules always permit redefinition of typedefs, as does C11. if (getLangOpts().Modules || getLangOpts().C11) return; // If we have a redefinition of a typedef in C, emit a warning. This warning // is normally mapped to an error, but can be controlled with // -Wtypedef-redefinition. If either the original or the redefinition is // in a system header, don't emit this for compatibility with GCC. if (getDiagnostics().getSuppressSystemWarnings() && (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || Context.getSourceManager().isInSystemHeader(New->getLocation()))) return; Diag(New->getLocation(), diag::warn_redefinition_of_typedef) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_definition); return; } /// DeclhasAttr - returns true if decl Declaration already has the target /// attribute. static bool DeclHasAttr(const Decl *D, const Attr *A) { // There can be multiple AvailabilityAttr in a Decl. Make sure we copy // all of them. It is mergeAvailabilityAttr in SemaDeclAttr.cpp that is // responsible for making sure they are consistent. const AvailabilityAttr *AA = dyn_cast<AvailabilityAttr>(A); if (AA) return false; // The following thread safety attributes can also be duplicated. switch (A->getKind()) { case attr::ExclusiveLocksRequired: case attr::SharedLocksRequired: case attr::LocksExcluded: case attr::ExclusiveLockFunction: case attr::SharedLockFunction: case attr::UnlockFunction: case attr::ExclusiveTrylockFunction: case attr::SharedTrylockFunction: case attr::GuardedBy: case attr::PtGuardedBy: case attr::AcquiredBefore: case attr::AcquiredAfter: return false; default: ; } const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); const AnnotateAttr *Ann = dyn_cast<AnnotateAttr>(A); for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) if ((*i)->getKind() == A->getKind()) { if (Ann) { if (Ann->getAnnotation() == cast<AnnotateAttr>(*i)->getAnnotation()) return true; continue; } // FIXME: Don't hardcode this check if (OA && isa<OwnershipAttr>(*i)) return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); return true; } return false; } static bool isAttributeTargetADefinition(Decl *D) { if (VarDecl *VD = dyn_cast<VarDecl>(D)) return VD->isThisDeclarationADefinition(); if (TagDecl *TD = dyn_cast<TagDecl>(D)) return TD->isCompleteDefinition() || TD->isBeingDefined(); return true; } /// Merge alignment attributes from \p Old to \p New, taking into account the /// special semantics of C11's _Alignas specifier and C++11's alignas attribute. /// /// \return \c true if any attributes were added to \p New. static bool mergeAlignedAttrs(Sema &S, NamedDecl *New, Decl *Old) { // Look for alignas attributes on Old, and pick out whichever attribute // specifies the strictest alignment requirement. AlignedAttr *OldAlignasAttr = 0; AlignedAttr *OldStrictestAlignAttr = 0; unsigned OldAlign = 0; for (specific_attr_iterator<AlignedAttr> I = Old->specific_attr_begin<AlignedAttr>(), E = Old->specific_attr_end<AlignedAttr>(); I != E; ++I) { // FIXME: We have no way of representing inherited dependent alignments // in a case like: // template<int A, int B> struct alignas(A) X; // template<int A, int B> struct alignas(B) X {}; // For now, we just ignore any alignas attributes which are not on the // definition in such a case. if (I->isAlignmentDependent()) return false; if (I->isAlignas()) OldAlignasAttr = *I; unsigned Align = I->getAlignment(S.Context); if (Align > OldAlign) { OldAlign = Align; OldStrictestAlignAttr = *I; } } // Look for alignas attributes on New. AlignedAttr *NewAlignasAttr = 0; unsigned NewAlign = 0; for (specific_attr_iterator<AlignedAttr> I = New->specific_attr_begin<AlignedAttr>(), E = New->specific_attr_end<AlignedAttr>(); I != E; ++I) { if (I->isAlignmentDependent()) return false; if (I->isAlignas()) NewAlignasAttr = *I; unsigned Align = I->getAlignment(S.Context); if (Align > NewAlign) NewAlign = Align; } if (OldAlignasAttr && NewAlignasAttr && OldAlign != NewAlign) { // Both declarations have 'alignas' attributes. We require them to match. // C++11 [dcl.align]p6 and C11 6.7.5/7 both come close to saying this, but // fall short. (If two declarations both have alignas, they must both match // every definition, and so must match each other if there is a definition.) // If either declaration only contains 'alignas(0)' specifiers, then it // specifies the natural alignment for the type. if (OldAlign == 0 || NewAlign == 0) { QualType Ty; if (ValueDecl *VD = dyn_cast<ValueDecl>(New)) Ty = VD->getType(); else Ty = S.Context.getTagDeclType(cast<TagDecl>(New)); if (OldAlign == 0) OldAlign = S.Context.getTypeAlign(Ty); if (NewAlign == 0) NewAlign = S.Context.getTypeAlign(Ty); } if (OldAlign != NewAlign) { S.Diag(NewAlignasAttr->getLocation(), diag::err_alignas_mismatch) << (unsigned)S.Context.toCharUnitsFromBits(OldAlign).getQuantity() << (unsigned)S.Context.toCharUnitsFromBits(NewAlign).getQuantity(); S.Diag(OldAlignasAttr->getLocation(), diag::note_previous_declaration); } } if (OldAlignasAttr && !NewAlignasAttr && isAttributeTargetADefinition(New)) { // C++11 [dcl.align]p6: // if any declaration of an entity has an alignment-specifier, // every defining declaration of that entity shall specify an // equivalent alignment. // C11 6.7.5/7: // If the definition of an object does not have an alignment // specifier, any other declaration of that object shall also // have no alignment specifier. S.Diag(New->getLocation(), diag::err_alignas_missing_on_definition) << OldAlignasAttr->isC11(); S.Diag(OldAlignasAttr->getLocation(), diag::note_alignas_on_declaration) << OldAlignasAttr->isC11(); } bool AnyAdded = false; // Ensure we have an attribute representing the strictest alignment. if (OldAlign > NewAlign) { AlignedAttr *Clone = OldStrictestAlignAttr->clone(S.Context); Clone->setInherited(true); New->addAttr(Clone); AnyAdded = true; } // Ensure we have an alignas attribute if the old declaration had one. if (OldAlignasAttr && !NewAlignasAttr && !(AnyAdded && OldStrictestAlignAttr->isAlignas())) { AlignedAttr *Clone = OldAlignasAttr->clone(S.Context); Clone->setInherited(true); New->addAttr(Clone); AnyAdded = true; } return AnyAdded; } static bool mergeDeclAttribute(Sema &S, NamedDecl *D, InheritableAttr *Attr, bool Override) { InheritableAttr *NewAttr = NULL; unsigned AttrSpellingListIndex = Attr->getSpellingListIndex(); if (AvailabilityAttr *AA = dyn_cast<AvailabilityAttr>(Attr)) NewAttr = S.mergeAvailabilityAttr(D, AA->getRange(), AA->getPlatform(), AA->getIntroduced(), AA->getDeprecated(), AA->getObsoleted(), AA->getUnavailable(), AA->getMessage(), Override, AttrSpellingListIndex); else if (VisibilityAttr *VA = dyn_cast<VisibilityAttr>(Attr)) NewAttr = S.mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility(), AttrSpellingListIndex); else if (TypeVisibilityAttr *VA = dyn_cast<TypeVisibilityAttr>(Attr)) NewAttr = S.mergeTypeVisibilityAttr(D, VA->getRange(), VA->getVisibility(), AttrSpellingListIndex); else if (DLLImportAttr *ImportA = dyn_cast<DLLImportAttr>(Attr)) NewAttr = S.mergeDLLImportAttr(D, ImportA->getRange(), AttrSpellingListIndex); else if (DLLExportAttr *ExportA = dyn_cast<DLLExportAttr>(Attr)) NewAttr = S.mergeDLLExportAttr(D, ExportA->getRange(), AttrSpellingListIndex); else if (FormatAttr *FA = dyn_cast<FormatAttr>(Attr)) NewAttr = S.mergeFormatAttr(D, FA->getRange(), FA->getType(), FA->getFormatIdx(), FA->getFirstArg(), AttrSpellingListIndex); else if (SectionAttr *SA = dyn_cast<SectionAttr>(Attr)) NewAttr = S.mergeSectionAttr(D, SA->getRange(), SA->getName(), AttrSpellingListIndex); else if (isa<AlignedAttr>(Attr)) // AlignedAttrs are handled separately, because we need to handle all // such attributes on a declaration at the same time. NewAttr = 0; else if (!DeclHasAttr(D, Attr)) NewAttr = cast<InheritableAttr>(Attr->clone(S.Context)); if (NewAttr) { NewAttr->setInherited(true); D->addAttr(NewAttr); return true; } return false; } static const Decl *getDefinition(const Decl *D) { if (const TagDecl *TD = dyn_cast<TagDecl>(D)) return TD->getDefinition(); if (const VarDecl *VD = dyn_cast<VarDecl>(D)) return VD->getDefinition(); if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { const FunctionDecl* Def; if (FD->hasBody(Def)) return Def; } return NULL; } static bool hasAttribute(const Decl *D, attr::Kind Kind) { for (Decl::attr_iterator I = D->attr_begin(), E = D->attr_end(); I != E; ++I) { Attr *Attribute = *I; if (Attribute->getKind() == Kind) return true; } return false; } /// checkNewAttributesAfterDef - If we already have a definition, check that /// there are no new attributes in this declaration. static void checkNewAttributesAfterDef(Sema &S, Decl *New, const Decl *Old) { if (!New->hasAttrs()) return; const Decl *Def = getDefinition(Old); if (!Def || Def == New) return; AttrVec &NewAttributes = New->getAttrs(); for (unsigned I = 0, E = NewAttributes.size(); I != E;) { const Attr *NewAttribute = NewAttributes[I]; if (hasAttribute(Def, NewAttribute->getKind())) { ++I; continue; // regular attr merging will take care of validating this. } if (isa<C11NoReturnAttr>(NewAttribute)) { // C's _Noreturn is allowed to be added to a function after it is defined. ++I; continue; } else if (const AlignedAttr *AA = dyn_cast<AlignedAttr>(NewAttribute)) { if (AA->isAlignas()) { // C++11 [dcl.align]p6: // if any declaration of an entity has an alignment-specifier, // every defining declaration of that entity shall specify an // equivalent alignment. // C11 6.7.5/7: // If the definition of an object does not have an alignment // specifier, any other declaration of that object shall also // have no alignment specifier. S.Diag(Def->getLocation(), diag::err_alignas_missing_on_definition) << AA->isC11(); S.Diag(NewAttribute->getLocation(), diag::note_alignas_on_declaration) << AA->isC11(); NewAttributes.erase(NewAttributes.begin() + I); --E; continue; } } S.Diag(NewAttribute->getLocation(), diag::warn_attribute_precede_definition); S.Diag(Def->getLocation(), diag::note_previous_definition); NewAttributes.erase(NewAttributes.begin() + I); --E; } } /// mergeDeclAttributes - Copy attributes from the Old decl to the New one. void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old, AvailabilityMergeKind AMK) { if (!Old->hasAttrs() && !New->hasAttrs()) return; // attributes declared post-definition are currently ignored checkNewAttributesAfterDef(*this, New, Old); if (!Old->hasAttrs()) return; bool foundAny = New->hasAttrs(); // Ensure that any moving of objects within the allocated map is done before // we process them. if (!foundAny) New->setAttrs(AttrVec()); for (specific_attr_iterator<InheritableAttr> i = Old->specific_attr_begin<InheritableAttr>(), e = Old->specific_attr_end<InheritableAttr>(); i != e; ++i) { bool Override = false; // Ignore deprecated/unavailable/availability attributes if requested. if (isa<DeprecatedAttr>(*i) || isa<UnavailableAttr>(*i) || isa<AvailabilityAttr>(*i)) { switch (AMK) { case AMK_None: continue; case AMK_Redeclaration: break; case AMK_Override: Override = true; break; } } if (mergeDeclAttribute(*this, New, *i, Override)) foundAny = true; } if (mergeAlignedAttrs(*this, New, Old)) foundAny = true; if (!foundAny) New->dropAttrs(); } /// mergeParamDeclAttributes - Copy attributes from the old parameter /// to the new one. static void mergeParamDeclAttributes(ParmVarDecl *newDecl, const ParmVarDecl *oldDecl, Sema &S) { // C++11 [dcl.attr.depend]p2: // The first declaration of a function shall specify the // carries_dependency attribute for its declarator-id if any declaration // of the function specifies the carries_dependency attribute. if (newDecl->hasAttr<CarriesDependencyAttr>() && !oldDecl->hasAttr<CarriesDependencyAttr>()) { S.Diag(newDecl->getAttr<CarriesDependencyAttr>()->getLocation(), diag::err_carries_dependency_missing_on_first_decl) << 1/*Param*/; // Find the first declaration of the parameter. // FIXME: Should we build redeclaration chains for function parameters? const FunctionDecl *FirstFD = cast<FunctionDecl>(oldDecl->getDeclContext())->getFirstDeclaration(); const ParmVarDecl *FirstVD = FirstFD->getParamDecl(oldDecl->getFunctionScopeIndex()); S.Diag(FirstVD->getLocation(), diag::note_carries_dependency_missing_first_decl) << 1/*Param*/; } if (!oldDecl->hasAttrs()) return; bool foundAny = newDecl->hasAttrs(); // Ensure that any moving of objects within the allocated map is // done before we process them. if (!foundAny) newDecl->setAttrs(AttrVec()); for (specific_attr_iterator<InheritableParamAttr> i = oldDecl->specific_attr_begin<InheritableParamAttr>(), e = oldDecl->specific_attr_end<InheritableParamAttr>(); i != e; ++i) { if (!DeclHasAttr(newDecl, *i)) { InheritableAttr *newAttr = cast<InheritableParamAttr>((*i)->clone(S.Context)); newAttr->setInherited(true); newDecl->addAttr(newAttr); foundAny = true; } } if (!foundAny) newDecl->dropAttrs(); } namespace { /// Used in MergeFunctionDecl to keep track of function parameters in /// C. struct GNUCompatibleParamWarning { ParmVarDecl *OldParm; ParmVarDecl *NewParm; QualType PromotedType; }; } /// getSpecialMember - get the special member enum for a method. Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { if (Ctor->isDefaultConstructor()) return Sema::CXXDefaultConstructor; if (Ctor->isCopyConstructor()) return Sema::CXXCopyConstructor; if (Ctor->isMoveConstructor()) return Sema::CXXMoveConstructor; } else if (isa<CXXDestructorDecl>(MD)) { return Sema::CXXDestructor; } else if (MD->isCopyAssignmentOperator()) { return Sema::CXXCopyAssignment; } else if (MD->isMoveAssignmentOperator()) { return Sema::CXXMoveAssignment; } return Sema::CXXInvalid; } /// canRedefineFunction - checks if a function can be redefined. Currently, /// only extern inline functions can be redefined, and even then only in /// GNU89 mode. static bool canRedefineFunction(const FunctionDecl *FD, const LangOptions& LangOpts) { return ((FD->hasAttr<GNUInlineAttr>() || LangOpts.GNUInline) && !LangOpts.CPlusPlus && FD->isInlineSpecified() && FD->getStorageClass() == SC_Extern); } /// Is the given calling convention the ABI default for the given /// declaration? static bool isABIDefaultCC(Sema &S, CallingConv CC, FunctionDecl *D) { CallingConv ABIDefaultCC; if (isa<CXXMethodDecl>(D) && cast<CXXMethodDecl>(D)->isInstance()) { ABIDefaultCC = S.Context.getDefaultCXXMethodCallConv(D->isVariadic()); } else { // Free C function or a static method. ABIDefaultCC = (S.Context.getLangOpts().MRTD ? CC_X86StdCall : CC_C); } return ABIDefaultCC == CC; } template <typename T> static bool haveIncompatibleLanguageLinkages(const T *Old, const T *New) { const DeclContext *DC = Old->getDeclContext(); if (DC->isRecord()) return false; LanguageLinkage OldLinkage = Old->getLanguageLinkage(); if (OldLinkage == CXXLanguageLinkage && New->isInExternCContext()) return true; if (OldLinkage == CLanguageLinkage && New->isInExternCXXContext()) return true; return false; } /// MergeFunctionDecl - We just parsed a function 'New' from /// declarator D which has the same name and scope as a previous /// declaration 'Old'. Figure out how to resolve this situation, /// merging decls or emitting diagnostics as appropriate. /// /// In C++, New and Old must be declarations that are not /// overloaded. Use IsOverload to determine whether New and Old are /// overloaded, and to select the Old declaration that New should be /// merged with. /// /// Returns true if there was an error, false otherwise. bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, Scope *S) { // Verify the old decl was also a function. FunctionDecl *Old = 0; if (FunctionTemplateDecl *OldFunctionTemplate = dyn_cast<FunctionTemplateDecl>(OldD)) Old = OldFunctionTemplate->getTemplatedDecl(); else Old = dyn_cast<FunctionDecl>(OldD); if (!Old) { if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { if (New->getFriendObjectKind()) { Diag(New->getLocation(), diag::err_using_decl_friend); Diag(Shadow->getTargetDecl()->getLocation(), diag::note_using_decl_target); Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl) << 0; return true; } Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); Diag(Shadow->getTargetDecl()->getLocation(), diag::note_using_decl_target); Diag(Shadow->getUsingDecl()->getLocation(), diag::note_using_decl) << 0; return true; } Diag(New->getLocation(), diag::err_redefinition_different_kind) << New->getDeclName(); Diag(OldD->getLocation(), diag::note_previous_definition); return true; } // If the old declaration is invalid, just give up here. if (Old->isInvalidDecl()) return true; // Determine whether the previous declaration was a definition, // implicit declaration, or a declaration. diag::kind PrevDiag; if (Old->isThisDeclarationADefinition()) PrevDiag = diag::note_previous_definition; else if (Old->isImplicit()) PrevDiag = diag::note_previous_implicit_declaration; else PrevDiag = diag::note_previous_declaration; QualType OldQType = Context.getCanonicalType(Old->getType()); QualType NewQType = Context.getCanonicalType(New->getType()); // Don't complain about this if we're in GNU89 mode and the old function // is an extern inline function. // Don't complain about specializations. They are not supposed to have // storage classes. if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && New->getStorageClass() == SC_Static && Old->hasExternalFormalLinkage() && !New->getTemplateSpecializationInfo() && !canRedefineFunction(Old, getLangOpts())) { if (getLangOpts().MicrosoftExt) { Diag(New->getLocation(), diag::warn_static_non_static) << New; Diag(Old->getLocation(), PrevDiag); } else { Diag(New->getLocation(), diag::err_static_non_static) << New; Diag(Old->getLocation(), PrevDiag); return true; } } // If a function is first declared with a calling convention, but is // later declared or defined without one, the second decl assumes the // calling convention of the first. // // It's OK if a function is first declared without a calling convention, // but is later declared or defined with the default calling convention. // // For the new decl, we have to look at the NON-canonical type to tell the // difference between a function that really doesn't have a calling // convention and one that is declared cdecl. That's because in // canonicalization (see ASTContext.cpp), cdecl is canonicalized away // because it is the default calling convention. // // Note also that we DO NOT return at this point, because we still have // other tests to run. const FunctionType *OldType = cast<FunctionType>(OldQType); const FunctionType *NewType = New->getType()->getAs<FunctionType>(); FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); bool RequiresAdjustment = false; if (OldTypeInfo.getCC() == NewTypeInfo.getCC()) { // Fast path: nothing to do. // Inherit the CC from the previous declaration if it was specified // there but not here. } else if (NewTypeInfo.getCC() == CC_Default) { NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); RequiresAdjustment = true; // Don't complain about mismatches when the default CC is // effectively the same as the explict one. Only Old decl contains correct // information about storage class of CXXMethod. } else if (OldTypeInfo.getCC() == CC_Default && isABIDefaultCC(*this, NewTypeInfo.getCC(), Old)) { NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); RequiresAdjustment = true; } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), NewTypeInfo.getCC())) { // Calling conventions really aren't compatible, so complain. Diag(New->getLocation(), diag::err_cconv_change) << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) << (OldTypeInfo.getCC() == CC_Default) << (OldTypeInfo.getCC() == CC_Default ? "" : FunctionType::getNameForCallConv(OldTypeInfo.getCC())); Diag(Old->getLocation(), diag::note_previous_declaration); return true; } // FIXME: diagnose the other way around? if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { NewTypeInfo = NewTypeInfo.withNoReturn(true); RequiresAdjustment = true; } // Merge regparm attribute. if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() || OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { if (NewTypeInfo.getHasRegParm()) { Diag(New->getLocation(), diag::err_regparm_mismatch) << NewType->getRegParmType() << OldType->getRegParmType(); Diag(Old->getLocation(), diag::note_previous_declaration); return true; } NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); RequiresAdjustment = true; } // Merge ns_returns_retained attribute. if (OldTypeInfo.getProducesResult() != NewTypeInfo.getProducesResult()) { if (NewTypeInfo.getProducesResult()) { Diag(New->getLocation(), diag::err_returns_retained_mismatch); Diag(Old->getLocation(), diag::note_previous_declaration); return true; } NewTypeInfo = NewTypeInfo.withProducesResult(true); RequiresAdjustment = true; } if (RequiresAdjustment) { NewType = Context.adjustFunctionType(NewType, NewTypeInfo); New->setType(QualType(NewType, 0)); NewQType = Context.getCanonicalType(New->getType()); } // If this redeclaration makes the function inline, we may need to add it to // UndefinedButUsed. if (!Old->isInlined() && New->isInlined() && !New->hasAttr<GNUInlineAttr>() && (getLangOpts().CPlusPlus || !getLangOpts().GNUInline) && Old->isUsed(false) && !Old->isDefined() && !New->isThisDeclarationADefinition()) UndefinedButUsed.insert(std::make_pair(Old->getCanonicalDecl(), SourceLocation())); // If this redeclaration makes it newly gnu_inline, we don't want to warn // about it. if (New->hasAttr<GNUInlineAttr>() && Old->isInlined() && !Old->hasAttr<GNUInlineAttr>()) { UndefinedButUsed.erase(Old->getCanonicalDecl()); } if (getLangOpts().CPlusPlus) { // (C++98 13.1p2): // Certain function declarations cannot be overloaded: // -- Function declarations that differ only in the return type // cannot be overloaded. // Go back to the type source info to compare the declared return types, // per C++1y [dcl.type.auto]p??: // Redeclarations or specializations of a function or function template // with a declared return type that uses a placeholder type shall also // use that placeholder, not a deduced type. QualType OldDeclaredReturnType = (Old->getTypeSourceInfo() ? Old->getTypeSourceInfo()->getType()->castAs<FunctionType>() : OldType)->getResultType(); QualType NewDeclaredReturnType = (New->getTypeSourceInfo() ? New->getTypeSourceInfo()->getType()->castAs<FunctionType>() : NewType)->getResultType(); QualType ResQT; if (!Context.hasSameType(OldDeclaredReturnType, NewDeclaredReturnType)) { if (NewDeclaredReturnType->isObjCObjectPointerType() && OldDeclaredReturnType->isObjCObjectPointerType()) ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); if (ResQT.isNull()) { if (New->isCXXClassMember() && New->isOutOfLine()) Diag(New->getLocation(), diag::err_member_def_does_not_match_ret_type) << New; else Diag(New->getLocation(), diag::err_ovl_diff_return_type); Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); return true; } else NewQType = ResQT; } QualType OldReturnType = OldType->getResultType(); QualType NewReturnType = cast<FunctionType>(NewQType)->getResultType(); if (OldReturnType != NewReturnType) { // If this function has a deduced return type and has already been // defined, copy the deduced value from the old declaration. AutoType *OldAT = Old->getResultType()->getContainedAutoType(); if (OldAT && OldAT->isDeduced()) { New->setType(SubstAutoType(New->getType(), OldAT->getDeducedType())); NewQType = Context.getCanonicalType( SubstAutoType(NewQType, OldAT->getDeducedType())); } } const CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old); CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New); if (OldMethod && NewMethod) { // Preserve triviality. NewMethod->setTrivial(OldMethod->isTrivial()); // MSVC allows explicit template specialization at class scope: // 2 CXMethodDecls referring to the same function will be injected. // We don't want a redeclartion error. bool IsClassScopeExplicitSpecialization = OldMethod->isFunctionTemplateSpecialization() && NewMethod->isFunctionTemplateSpecialization(); bool isFriend = NewMethod->getFriendObjectKind(); if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord() && !IsClassScopeExplicitSpecialization) { // -- Member function declarations with the same name and the // same parameter types cannot be overloaded if any of them // is a static member function declaration. if (OldMethod->isStatic() != NewMethod->isStatic()) { Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); return true; } // C++ [class.mem]p1: // [...] A member shall not be declared twice in the // member-specification, except that a nested class or member // class template can be declared and then later defined. if (ActiveTemplateInstantiations.empty()) { unsigned NewDiag; if (isa<CXXConstructorDecl>(OldMethod)) NewDiag = diag::err_constructor_redeclared; else if (isa<CXXDestructorDecl>(NewMethod)) NewDiag = diag::err_destructor_redeclared; else if (isa<CXXConversionDecl>(NewMethod)) NewDiag = diag::err_conv_function_redeclared; else NewDiag = diag::err_member_redeclared; Diag(New->getLocation(), NewDiag); } else { Diag(New->getLocation(), diag::err_member_redeclared_in_instantiation) << New << New->getType(); } Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); // Complain if this is an explicit declaration of a special // member that was initially declared implicitly. // // As an exception, it's okay to befriend such methods in order // to permit the implicit constructor/destructor/operator calls. } else if (OldMethod->isImplicit()) { if (isFriend) { NewMethod->setImplicit(); } else { Diag(NewMethod->getLocation(), diag::err_definition_of_implicitly_declared_member) << New << getSpecialMember(OldMethod); return true; } } else if (OldMethod->isExplicitlyDefaulted() && !isFriend) { Diag(NewMethod->getLocation(), diag::err_definition_of_explicitly_defaulted_member) << getSpecialMember(OldMethod); return true; } } // C++11 [dcl.attr.noreturn]p1: // The first declaration of a function shall specify the noreturn // attribute if any declaration of that function specifies the noreturn // attribute. if (New->hasAttr<CXX11NoReturnAttr>() && !Old->hasAttr<CXX11NoReturnAttr>()) { Diag(New->getAttr<CXX11NoReturnAttr>()->getLocation(), diag::err_noreturn_missing_on_first_decl); Diag(Old->getFirstDeclaration()->getLocation(), diag::note_noreturn_missing_first_decl); } // C++11 [dcl.attr.depend]p2: // The first declaration of a function shall specify the // carries_dependency attribute for its declarator-id if any declaration // of the function specifies the carries_dependency attribute. if (New->hasAttr<CarriesDependencyAttr>() && !Old->hasAttr<CarriesDependencyAttr>()) { Diag(New->getAttr<CarriesDependencyAttr>()->getLocation(), diag::err_carries_dependency_missing_on_first_decl) << 0/*Function*/; Diag(Old->getFirstDeclaration()->getLocation(), diag::note_carries_dependency_missing_first_decl) << 0/*Function*/; } // (C++98 8.3.5p3): // All declarations for a function shall agree exactly in both the // return type and the parameter-type-list. // We also want to respect all the extended bits except noreturn. // noreturn should now match unless the old type info didn't have it. QualType OldQTypeForComparison = OldQType; if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { assert(OldQType == QualType(OldType, 0)); const FunctionType *OldTypeForComparison = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); OldQTypeForComparison = QualType(OldTypeForComparison, 0); assert(OldQTypeForComparison.isCanonical()); } if (haveIncompatibleLanguageLinkages(Old, New)) { Diag(New->getLocation(), diag::err_different_language_linkage) << New; Diag(Old->getLocation(), PrevDiag); return true; } if (OldQTypeForComparison == NewQType) return MergeCompatibleFunctionDecls(New, Old, S); // Fall through for conflicting redeclarations and redefinitions. } // C: Function types need to be compatible, not identical. This handles // duplicate function decls like "void f(int); void f(enum X);" properly. if (!getLangOpts().CPlusPlus && Context.typesAreCompatible(OldQType, NewQType)) { const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); const FunctionProtoType *OldProto = 0; if (isa<FunctionNoProtoType>(NewFuncType) && (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { // The old declaration provided a function prototype, but the // new declaration does not. Merge in the prototype. assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), OldProto->arg_type_end()); NewQType = Context.getFunctionType(NewFuncType->getResultType(), ParamTypes, OldProto->getExtProtoInfo()); New->setType(NewQType); New->setHasInheritedPrototype(); // Synthesize a parameter for each argument type. SmallVector<ParmVarDecl*, 16> Params; for (FunctionProtoType::arg_type_iterator ParamType = OldProto->arg_type_begin(), ParamEnd = OldProto->arg_type_end(); ParamType != ParamEnd; ++ParamType) { ParmVarDecl *Param = ParmVarDecl::Create(Context, New, SourceLocation(), SourceLocation(), 0, *ParamType, /*TInfo=*/0, SC_None, 0); Param->setScopeInfo(0, Params.size()); Param->setImplicit(); Params.push_back(Param); } New->setParams(Params); } return MergeCompatibleFunctionDecls(New, Old, S); } // GNU C permits a K&R definition to follow a prototype declaration // if the declared types of the parameters in the K&R definition // match the types in the prototype declaration, even when the // promoted types of the parameters from the K&R definition differ // from the types in the prototype. GCC then keeps the types from // the prototype. // // If a variadic prototype is followed by a non-variadic K&R definition, // the K&R definition becomes variadic. This is sort of an edge case, but // it's legal per the standard depending on how you read C99 6.7.5.3p15 and // C99 6.9.1p8. if (!getLangOpts().CPlusPlus && Old->hasPrototype() && !New->hasPrototype() && New->getType()->getAs<FunctionProtoType>() && Old->getNumParams() == New->getNumParams()) { SmallVector<QualType, 16> ArgTypes; SmallVector<GNUCompatibleParamWarning, 16> Warnings; const FunctionProtoType *OldProto = Old->getType()->getAs<FunctionProtoType>(); const FunctionProtoType *NewProto = New->getType()->getAs<FunctionProtoType>(); // Determine whether this is the GNU C extension. QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), NewProto->getResultType()); bool LooseCompatible = !MergedReturn.isNull(); for (unsigned Idx = 0, End = Old->getNumParams(); LooseCompatible && Idx != End; ++Idx) { ParmVarDecl *OldParm = Old->getParamDecl(Idx); ParmVarDecl *NewParm = New->getParamDecl(Idx); if (Context.typesAreCompatible(OldParm->getType(), NewProto->getArgType(Idx))) { ArgTypes.push_back(NewParm->getType()); } else if (Context.typesAreCompatible(OldParm->getType(), NewParm->getType(), /*CompareUnqualified=*/true)) { GNUCompatibleParamWarning Warn = { OldParm, NewParm, NewProto->getArgType(Idx) }; Warnings.push_back(Warn); ArgTypes.push_back(NewParm->getType()); } else LooseCompatible = false; } if (LooseCompatible) { for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { Diag(Warnings[Warn].NewParm->getLocation(), diag::ext_param_promoted_not_compatible_with_prototype) << Warnings[Warn].PromotedType << Warnings[Warn].OldParm->getType(); if (Warnings[Warn].OldParm->getLocation().isValid()) Diag(Warnings[Warn].OldParm->getLocation(), diag::note_previous_declaration); } New->setType(Context.getFunctionType(MergedReturn, ArgTypes, OldProto->getExtProtoInfo())); return MergeCompatibleFunctionDecls(New, Old, S); } // Fall through to diagnose conflicting types. } // A function that has already been declared has been redeclared or // defined with a different type; show an appropriate diagnostic. // If the previous declaration was an implicitly-generated builtin // declaration, then at the very least we should use a specialized note. unsigned BuiltinID; if (Old->isImplicit() && (BuiltinID = Old->getBuiltinID())) { // If it's actually a library-defined builtin function like 'malloc' // or 'printf', just warn about the incompatible redeclaration. if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; Diag(Old->getLocation(), diag::note_previous_builtin_declaration) << Old << Old->getType(); // If this is a global redeclaration, just forget hereafter // about the "builtin-ness" of the function. // // Doing this for local extern declarations is problematic. If // the builtin declaration remains visible, a second invalid // local declaration will produce a hard error; if it doesn't // remain visible, a single bogus local redeclaration (which is // actually only a warning) could break all the downstream code. if (!New->getDeclContext()->isFunctionOrMethod()) New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); return false; } PrevDiag = diag::note_previous_builtin_declaration; } Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); return true; } /// \brief Completes the merge of two function declarations that are /// known to be compatible. /// /// This routine handles the merging of attributes and other /// properties of function declarations form the old declaration to /// the new declaration, once we know that New is in fact a /// redeclaration of Old. /// /// \returns false bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old, Scope *S) { // Merge the attributes mergeDeclAttributes(New, Old); // Merge "pure" flag. if (Old->isPure()) New->setPure(); // Merge "used" flag. if (Old->isUsed(false)) New->setUsed(); // Merge attributes from the parameters. These can mismatch with K&R // declarations. if (New->getNumParams() == Old->getNumParams()) for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i), *this); if (getLangOpts().CPlusPlus) return MergeCXXFunctionDecl(New, Old, S); // Merge the function types so the we get the composite types for the return // and argument types. QualType Merged = Context.mergeTypes(Old->getType(), New->getType()); if (!Merged.isNull()) New->setType(Merged); return false; } void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, ObjCMethodDecl *oldMethod) { // Merge the attributes, including deprecated/unavailable AvailabilityMergeKind MergeKind = isa<ObjCImplDecl>(newMethod->getDeclContext()) ? AMK_Redeclaration : AMK_Override; mergeDeclAttributes(newMethod, oldMethod, MergeKind); // Merge attributes from the parameters. ObjCMethodDecl::param_const_iterator oi = oldMethod->param_begin(), oe = oldMethod->param_end(); for (ObjCMethodDecl::param_iterator ni = newMethod->param_begin(), ne = newMethod->param_end(); ni != ne && oi != oe; ++ni, ++oi) mergeParamDeclAttributes(*ni, *oi, *this); CheckObjCMethodOverride(newMethod, oldMethod); } /// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and /// scope as a previous declaration 'Old'. Figure out how to merge their types, /// emitting diagnostics as appropriate. /// /// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back /// to here in AddInitializerToDecl. We can't check them before the initializer /// is attached. void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old, bool OldWasHidden) { if (New->isInvalidDecl() || Old->isInvalidDecl()) return; QualType MergedT; if (getLangOpts().CPlusPlus) { if (New->getType()->isUndeducedType()) { // We don't know what the new type is until the initializer is attached. return; } else if (Context.hasSameType(New->getType(), Old->getType())) { // These could still be something that needs exception specs checked. return MergeVarDeclExceptionSpecs(New, Old); } // C++ [basic.link]p10: // [...] the types specified by all declarations referring to a given // object or function shall be identical, except that declarations for an // array object can specify array types that differ by the presence or // absence of a major array bound (8.3.4). else if (Old->getType()->isIncompleteArrayType() && New->getType()->isArrayType()) { const ArrayType *OldArray = Context.getAsArrayType(Old->getType()); const ArrayType *NewArray = Context.getAsArrayType(New->getType()); if (Context.hasSameType(OldArray->getElementType(), NewArray->getElementType())) MergedT = New->getType(); } else if (Old->getType()->isArrayType() && New->getType()->isIncompleteArrayType()) { const ArrayType *OldArray = Context.getAsArrayType(Old->getType()); const ArrayType *NewArray = Context.getAsArrayType(New->getType()); if (Context.hasSameType(OldArray->getElementType(), NewArray->getElementType())) MergedT = Old->getType(); } else if (New->getType()->isObjCObjectPointerType() && Old->getType()->isObjCObjectPointerType()) { MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); } } else { MergedT = Context.mergeTypes(New->getType(), Old->getType()); } if (MergedT.isNull()) { Diag(New->getLocation(), diag::err_redefinition_different_type) << New->getDeclName() << New->getType() << Old->getType(); Diag(Old->getLocation(), diag::note_previous_definition); return New->setInvalidDecl(); } // Don't actually update the type on the new declaration if the old // declaration was a extern declaration in a different scope. if (!OldWasHidden) New->setType(MergedT); } /// MergeVarDecl - We just parsed a variable 'New' which has the same name /// and scope as a previous declaration 'Old'. Figure out how to resolve this /// situation, merging decls or emitting diagnostics as appropriate. /// /// Tentative definition rules (C99 6.9.2p2) are checked by /// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative /// definitions here, since the initializer hasn't been attached. /// void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous, bool PreviousWasHidden) { // If the new decl is already invalid, don't do any other checking. if (New->isInvalidDecl()) return; // Verify the old decl was also a variable. VarDecl *Old = 0; if (!Previous.isSingleResult() || !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { Diag(New->getLocation(), diag::err_redefinition_different_kind) << New->getDeclName(); Diag(Previous.getRepresentativeDecl()->getLocation(), diag::note_previous_definition); return New->setInvalidDecl(); } if (!shouldLinkPossiblyHiddenDecl(Old, New)) return; // C++ [class.mem]p1: // A member shall not be declared twice in the member-specification [...] // // Here, we need only consider static data members. if (Old->isStaticDataMember() && !New->isOutOfLine()) { Diag(New->getLocation(), diag::err_duplicate_member) << New->getIdentifier(); Diag(Old->getLocation(), diag::note_previous_declaration); New->setInvalidDecl(); } mergeDeclAttributes(New, Old); // Warn if an already-declared variable is made a weak_import in a subsequent // declaration if (New->getAttr<WeakImportAttr>() && Old->getStorageClass() == SC_None && !Old->getAttr<WeakImportAttr>()) { Diag(New->getLocation(), diag::warn_weak_import) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_definition); // Remove weak_import attribute on new declaration. New->dropAttr<WeakImportAttr>(); } // Merge the types. MergeVarDeclTypes(New, Old, PreviousWasHidden); if (New->isInvalidDecl()) return; // [dcl.stc]p8: Check if we have a non-static decl followed by a static. if (New->getStorageClass() == SC_Static && !New->isStaticDataMember() && Old->hasExternalFormalLinkage()) { Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_definition); return New->setInvalidDecl(); } // C99 6.2.2p4: // For an identifier declared with the storage-class specifier // extern in a scope in which a prior declaration of that // identifier is visible,23) if the prior declaration specifies // internal or external linkage, the linkage of the identifier at // the later declaration is the same as the linkage specified at // the prior declaration. If no prior declaration is visible, or // if the prior declaration specifies no linkage, then the // identifier has external linkage. if (New->hasExternalStorage() && Old->hasLinkage()) /* Okay */; else if (New->getCanonicalDecl()->getStorageClass() != SC_Static && !New->isStaticDataMember() && Old->getCanonicalDecl()->getStorageClass() == SC_Static) { Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_definition); return New->setInvalidDecl(); } // Check if extern is followed by non-extern and vice-versa. if (New->hasExternalStorage() && !Old->hasLinkage() && Old->isLocalVarDecl()) { Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_definition); return New->setInvalidDecl(); } if (Old->hasLinkage() && New->isLocalVarDecl() && !New->hasExternalStorage()) { Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_definition); return New->setInvalidDecl(); } // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. // FIXME: The test for external storage here seems wrong? We still // need to check for mismatches. if (!New->hasExternalStorage() && !New->isFileVarDecl() && // Don't complain about out-of-line definitions of static members. !(Old->getLexicalDeclContext()->isRecord() && !New->getLexicalDeclContext()->isRecord())) { Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_definition); return New->setInvalidDecl(); } if (New->getTLSKind() != Old->getTLSKind()) { if (!Old->getTLSKind()) { Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_declaration); } else if (!New->getTLSKind()) { Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); Diag(Old->getLocation(), diag::note_previous_declaration); } else { // Do not allow redeclaration to change the variable between requiring // static and dynamic initialization. // FIXME: GCC allows this, but uses the TLS keyword on the first // declaration to determine the kind. Do we need to be compatible here? Diag(New->getLocation(), diag::err_thread_thread_different_kind) << New->getDeclName() << (New->getTLSKind() == VarDecl::TLS_Dynamic); Diag(Old->getLocation(), diag::note_previous_declaration); } } // C++ doesn't have tentative definitions, so go right ahead and check here. const VarDecl *Def; if (getLangOpts().CPlusPlus && New->isThisDeclarationADefinition() == VarDecl::Definition && (Def = Old->getDefinition())) { Diag(New->getLocation(), diag::err_redefinition) << New; Diag(Def->getLocation(), diag::note_previous_definition); New->setInvalidDecl(); return; } if (haveIncompatibleLanguageLinkages(Old, New)) { Diag(New->getLocation(), diag::err_different_language_linkage) << New; Diag(Old->getLocation(), diag::note_previous_definition); New->setInvalidDecl(); return; } // Merge "used" flag. if (Old->isUsed(false)) New->setUsed(); // Keep a chain of previous declarations. New->setPreviousDeclaration(Old); // Inherit access appropriately. New->setAccess(Old->getAccess()); } /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with /// no declarator (e.g. "struct foo;") is parsed. Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS) { return ParsedFreeStandingDeclSpec(S, AS, DS, MultiTemplateParamsArg()); } static void HandleTagNumbering(Sema &S, const TagDecl *Tag) { if (isa<CXXRecordDecl>(Tag->getParent())) { // If this tag is the direct child of a class, number it if // it is anonymous. if (!Tag->getName().empty() || Tag->getTypedefNameForAnonDecl()) return; MangleNumberingContext &MCtx = S.Context.getManglingNumberContext(Tag->getParent()); S.Context.setManglingNumber(Tag, MCtx.getManglingNumber(Tag)); return; } // If this tag isn't a direct child of a class, number it if it is local. Decl *ManglingContextDecl; if (MangleNumberingContext *MCtx = S.getCurrentMangleNumberContext(Tag->getDeclContext(), ManglingContextDecl)) { S.Context.setManglingNumber(Tag, MCtx->getManglingNumber(Tag)); } } /// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with /// no declarator (e.g. "struct foo;") is parsed. It also accepts template /// parameters to cope with template friend declarations. Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS, MultiTemplateParamsArg TemplateParams, bool IsExplicitInstantiation) { Decl *TagD = 0; TagDecl *Tag = 0; if (DS.getTypeSpecType() == DeclSpec::TST_class || DS.getTypeSpecType() == DeclSpec::TST_struct || DS.getTypeSpecType() == DeclSpec::TST_interface || DS.getTypeSpecType() == DeclSpec::TST_union || DS.getTypeSpecType() == DeclSpec::TST_enum) { TagD = DS.getRepAsDecl(); if (!TagD) // We probably had an error return 0; // Note that the above type specs guarantee that the // type rep is a Decl, whereas in many of the others // it's a Type. if (isa<TagDecl>(TagD)) Tag = cast<TagDecl>(TagD); else if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(TagD)) Tag = CTD->getTemplatedDecl(); } if (Tag) { HandleTagNumbering(*this, Tag); Tag->setFreeStanding(); if (Tag->isInvalidDecl()) return Tag; } if (unsigned TypeQuals = DS.getTypeQualifiers()) { // Enforce C99 6.7.3p2: "Types other than pointer types derived from object // or incomplete types shall not be restrict-qualified." if (TypeQuals & DeclSpec::TQ_restrict) Diag(DS.getRestrictSpecLoc(), diag::err_typecheck_invalid_restrict_not_pointer_noarg) << DS.getSourceRange(); } if (DS.isConstexprSpecified()) { // C++0x [dcl.constexpr]p1: constexpr can only be applied to declarations // and definitions of functions and variables. if (Tag) Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_tag) << (DS.getTypeSpecType() == DeclSpec::TST_class ? 0 : DS.getTypeSpecType() == DeclSpec::TST_struct ? 1 : DS.getTypeSpecType() == DeclSpec::TST_interface ? 2 : DS.getTypeSpecType() == DeclSpec::TST_union ? 3 : 4); else Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_no_declarators); // Don't emit warnings after this error. return TagD; } DiagnoseFunctionSpecifiers(DS); if (DS.isFriendSpecified()) { // If we're dealing with a decl but not a TagDecl, assume that // whatever routines created it handled the friendship aspect. if (TagD && !Tag) return 0; return ActOnFriendTypeDecl(S, DS, TemplateParams); } CXXScopeSpec &SS = DS.getTypeSpecScope(); bool IsExplicitSpecialization = !TemplateParams.empty() && TemplateParams.back()->size() == 0; if (Tag && SS.isNotEmpty() && !Tag->isCompleteDefinition() && !IsExplicitInstantiation && !IsExplicitSpecialization) { // Per C++ [dcl.type.elab]p1, a class declaration cannot have a // nested-name-specifier unless it is an explicit instantiation // or an explicit specialization. // Per C++ [dcl.enum]p1, an opaque-enum-declaration can't either. Diag(SS.getBeginLoc(), diag::err_standalone_class_nested_name_specifier) << (DS.getTypeSpecType() == DeclSpec::TST_class ? 0 : DS.getTypeSpecType() == DeclSpec::TST_struct ? 1 : DS.getTypeSpecType() == DeclSpec::TST_interface ? 2 : DS.getTypeSpecType() == DeclSpec::TST_union ? 3 : 4) << SS.getRange(); return 0; } // Track whether this decl-specifier declares anything. bool DeclaresAnything = true; // Handle anonymous struct definitions. if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { if (!Record->getDeclName() && Record->isCompleteDefinition() && DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { if (getLangOpts().CPlusPlus || Record->getDeclContext()->isRecord()) return BuildAnonymousStructOrUnion(S, DS, AS, Record); DeclaresAnything = false; } } // Check for Microsoft C extension: anonymous struct member. if (getLangOpts().MicrosoftExt && !getLangOpts().CPlusPlus && CurContext->isRecord() && DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { // Handle 2 kinds of anonymous struct: // struct STRUCT; // and // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag); if ((Record && Record->getDeclName() && !Record->isCompleteDefinition()) || (DS.getTypeSpecType() == DeclSpec::TST_typename && DS.getRepAsType().get()->isStructureType())) { Diag(DS.getLocStart(), diag::ext_ms_anonymous_struct) << DS.getSourceRange(); return BuildMicrosoftCAnonymousStruct(S, DS, Record); } } // Skip all the checks below if we have a type error. if (DS.getTypeSpecType() == DeclSpec::TST_error || (TagD && TagD->isInvalidDecl())) return TagD; if (getLangOpts().CPlusPlus && DS.getStorageClassSpec() != DeclSpec::SCS_typedef) if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) if (Enum->enumerator_begin() == Enum->enumerator_end() && !Enum->getIdentifier() && !Enum->isInvalidDecl()) DeclaresAnything = false; if (!DS.isMissingDeclaratorOk()) { // Customize diagnostic for a typedef missing a name. if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) Diag(DS.getLocStart(), diag::ext_typedef_without_a_name) << DS.getSourceRange(); else DeclaresAnything = false; } if (DS.isModulePrivateSpecified() && Tag && Tag->getDeclContext()->isFunctionOrMethod()) Diag(DS.getModulePrivateSpecLoc(), diag::err_module_private_local_class) << Tag->getTagKind() << FixItHint::CreateRemoval(DS.getModulePrivateSpecLoc()); ActOnDocumentableDecl(TagD); // C 6.7/2: // A declaration [...] shall declare at least a declarator [...], a tag, // or the members of an enumeration. // C++ [dcl.dcl]p3: // [If there are no declarators], and except for the declaration of an // unnamed bit-field, the decl-specifier-seq shall introduce one or more // names into the program, or shall redeclare a name introduced by a // previous declaration. if (!DeclaresAnything) { // In C, we allow this as a (popular) extension / bug. Don't bother // producing further diagnostics for redundant qualifiers after this. Diag(DS.getLocStart(), diag::ext_no_declarators) << DS.getSourceRange(); return TagD; } // C++ [dcl.stc]p1: // If a storage-class-specifier appears in a decl-specifier-seq, [...] the // init-declarator-list of the declaration shall not be empty. // C++ [dcl.fct.spec]p1: // If a cv-qualifier appears in a decl-specifier-seq, the // init-declarator-list of the declaration shall not be empty. // // Spurious qualifiers here appear to be valid in C. unsigned DiagID = diag::warn_standalone_specifier; if (getLangOpts().CPlusPlus) DiagID = diag::ext_standalone_specifier; // Note that a linkage-specification sets a storage class, but // 'extern "C" struct foo;' is actually valid and not theoretically // useless. if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) if (!DS.isExternInLinkageSpec() && SCS != DeclSpec::SCS_typedef) Diag(DS.getStorageClassSpecLoc(), DiagID) << DeclSpec::getSpecifierName(SCS); if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec()) Diag(DS.getThreadStorageClassSpecLoc(), DiagID) << DeclSpec::getSpecifierName(TSCS); if (DS.getTypeQualifiers()) { if (DS.getTypeQualifiers() & DeclSpec::TQ_const) Diag(DS.getConstSpecLoc(), DiagID) << "const"; if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) Diag(DS.getConstSpecLoc(), DiagID) << "volatile"; // Restrict is covered above. if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic) Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic"; } // Warn about ignored type attributes, for example: // __attribute__((aligned)) struct A; // Attributes should be placed after tag to apply to type declaration. if (!DS.getAttributes().empty()) { DeclSpec::TST TypeSpecType = DS.getTypeSpecType(); if (TypeSpecType == DeclSpec::TST_class || TypeSpecType == DeclSpec::TST_struct || TypeSpecType == DeclSpec::TST_interface || TypeSpecType == DeclSpec::TST_union || TypeSpecType == DeclSpec::TST_enum) { AttributeList* attrs = DS.getAttributes().getList(); while (attrs) { Diag(attrs->getLoc(), diag::warn_declspec_attribute_ignored) << attrs->getName() << (TypeSpecType == DeclSpec::TST_class ? 0 : TypeSpecType == DeclSpec::TST_struct ? 1 : TypeSpecType == DeclSpec::TST_union ? 2 : TypeSpecType == DeclSpec::TST_interface ? 3 : 4); attrs = attrs->getNext(); } } } return TagD; } /// We are trying to inject an anonymous member into the given scope; /// check if there's an existing declaration that can't be overloaded. /// /// \return true if this is a forbidden redeclaration static bool CheckAnonMemberRedeclaration(Sema &SemaRef, Scope *S, DeclContext *Owner, DeclarationName Name, SourceLocation NameLoc, unsigned diagnostic) { LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, Sema::ForRedeclaration); if (!SemaRef.LookupName(R, S)) return false; if (R.getAsSingle<TagDecl>()) return false; // Pick a representative declaration. NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); assert(PrevDecl && "Expected a non-null Decl"); if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) return false; SemaRef.Diag(NameLoc, diagnostic) << Name; SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); return true; } /// InjectAnonymousStructOrUnionMembers - Inject the members of the /// anonymous struct or union AnonRecord into the owning context Owner /// and scope S. This routine will be invoked just after we realize /// that an unnamed union or struct is actually an anonymous union or /// struct, e.g., /// /// @code /// union { /// int i; /// float f; /// }; // InjectAnonymousStructOrUnionMembers called here to inject i and /// // f into the surrounding scope.x /// @endcode /// /// This routine is recursive, injecting the names of nested anonymous /// structs/unions into the owning context and scope as well. static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, DeclContext *Owner, RecordDecl *AnonRecord, AccessSpecifier AS, SmallVectorImpl<NamedDecl *> &Chaining, bool MSAnonStruct) { unsigned diagKind = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl : diag::err_anonymous_struct_member_redecl; bool Invalid = false; // Look every FieldDecl and IndirectFieldDecl with a name. for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(), DEnd = AnonRecord->decls_end(); D != DEnd; ++D) { if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) && cast<NamedDecl>(*D)->getDeclName()) { ValueDecl *VD = cast<ValueDecl>(*D); if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), VD->getLocation(), diagKind)) { // C++ [class.union]p2: // The names of the members of an anonymous union shall be // distinct from the names of any other entity in the // scope in which the anonymous union is declared. Invalid = true; } else { // C++ [class.union]p2: // For the purpose of name lookup, after the anonymous union // definition, the members of the anonymous union are // considered to have been defined in the scope in which the // anonymous union is declared. unsigned OldChainingSize = Chaining.size(); if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) for (IndirectFieldDecl::chain_iterator PI = IF->chain_begin(), PE = IF->chain_end(); PI != PE; ++PI) Chaining.push_back(*PI); else Chaining.push_back(VD); assert(Chaining.size() >= 2); NamedDecl **NamedChain = new (SemaRef.Context)NamedDecl*[Chaining.size()]; for (unsigned i = 0; i < Chaining.size(); i++) NamedChain[i] = Chaining[i]; IndirectFieldDecl* IndirectField = IndirectFieldDecl::Create(SemaRef.Context, Owner, VD->getLocation(), VD->getIdentifier(), VD->getType(), NamedChain, Chaining.size()); IndirectField->setAccess(AS); IndirectField->setImplicit(); SemaRef.PushOnScopeChains(IndirectField, S); // That includes picking up the appropriate access specifier. if (AS != AS_none) IndirectField->setAccess(AS); Chaining.resize(OldChainingSize); } } } return Invalid; } /// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to /// a VarDecl::StorageClass. Any error reporting is up to the caller: /// illegal input values are mapped to SC_None. static StorageClass StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) { DeclSpec::SCS StorageClassSpec = DS.getStorageClassSpec(); assert(StorageClassSpec != DeclSpec::SCS_typedef && "Parser allowed 'typedef' as storage class VarDecl."); switch (StorageClassSpec) { case DeclSpec::SCS_unspecified: return SC_None; case DeclSpec::SCS_extern: if (DS.isExternInLinkageSpec()) return SC_None; return SC_Extern; case DeclSpec::SCS_static: return SC_Static; case DeclSpec::SCS_auto: return SC_Auto; case DeclSpec::SCS_register: return SC_Register; case DeclSpec::SCS_private_extern: return SC_PrivateExtern; // Illegal SCSs map to None: error reporting is up to the caller. case DeclSpec::SCS_mutable: // Fall through. case DeclSpec::SCS_typedef: return SC_None; } llvm_unreachable("unknown storage class specifier"); } /// BuildAnonymousStructOrUnion - Handle the declaration of an /// anonymous structure or union. Anonymous unions are a C++ feature /// (C++ [class.union]) and a C11 feature; anonymous structures /// are a C11 feature and GNU C++ extension. Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, AccessSpecifier AS, RecordDecl *Record) { DeclContext *Owner = Record->getDeclContext(); // Diagnose whether this anonymous struct/union is an extension. if (Record->isUnion() && !getLangOpts().CPlusPlus && !getLangOpts().C11) Diag(Record->getLocation(), diag::ext_anonymous_union); else if (!Record->isUnion() && getLangOpts().CPlusPlus) Diag(Record->getLocation(), diag::ext_gnu_anonymous_struct); else if (!Record->isUnion() && !getLangOpts().C11) Diag(Record->getLocation(), diag::ext_c11_anonymous_struct); // C and C++ require different kinds of checks for anonymous // structs/unions. bool Invalid = false; if (getLangOpts().CPlusPlus) { const char* PrevSpec = 0; unsigned DiagID; if (Record->isUnion()) { // C++ [class.union]p6: // Anonymous unions declared in a named namespace or in the // global namespace shall be declared static. if (DS.getStorageClassSpec() != DeclSpec::SCS_static && (isa<TranslationUnitDecl>(Owner) || (isa<NamespaceDecl>(Owner) && cast<NamespaceDecl>(Owner)->getDeclName()))) { Diag(Record->getLocation(), diag::err_anonymous_union_not_static) << FixItHint::CreateInsertion(Record->getLocation(), "static "); // Recover by adding 'static'. DS.SetStorageClassSpec(*this, DeclSpec::SCS_static, SourceLocation(), PrevSpec, DiagID); } // C++ [class.union]p6: // A storage class is not allowed in a declaration of an // anonymous union in a class scope. else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && isa<RecordDecl>(Owner)) { Diag(DS.getStorageClassSpecLoc(), diag::err_anonymous_union_with_storage_spec) << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc()); // Recover by removing the storage specifier. DS.SetStorageClassSpec(*this, DeclSpec::SCS_unspecified, SourceLocation(), PrevSpec, DiagID); } } // Ignore const/volatile/restrict qualifiers. if (DS.getTypeQualifiers()) { if (DS.getTypeQualifiers() & DeclSpec::TQ_const) Diag(DS.getConstSpecLoc(), diag::ext_anonymous_struct_union_qualified) << Record->isUnion() << "const" << FixItHint::CreateRemoval(DS.getConstSpecLoc()); if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) Diag(DS.getVolatileSpecLoc(), diag::ext_anonymous_struct_union_qualified) << Record->isUnion() << "volatile" << FixItHint::CreateRemoval(DS.getVolatileSpecLoc()); if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict) Diag(DS.getRestrictSpecLoc(), diag::ext_anonymous_struct_union_qualified) << Record->isUnion() << "restrict" << FixItHint::CreateRemoval(DS.getRestrictSpecLoc()); if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic) Diag(DS.getAtomicSpecLoc(), diag::ext_anonymous_struct_union_qualified) << Record->isUnion() << "_Atomic" << FixItHint::CreateRemoval(DS.getAtomicSpecLoc()); DS.ClearTypeQualifiers(); } // C++ [class.union]p2: // The member-specification of an anonymous union shall only // define non-static data members. [Note: nested types and // functions cannot be declared within an anonymous union. ] for (DeclContext::decl_iterator Mem = Record->decls_begin(), MemEnd = Record->decls_end(); Mem != MemEnd; ++Mem) { if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { // C++ [class.union]p3: // An anonymous union shall not have private or protected // members (clause 11). assert(FD->getAccess() != AS_none); if (FD->getAccess() != AS_public) { Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); Invalid = true; } // C++ [class.union]p1 // An object of a class with a non-trivial constructor, a non-trivial // copy constructor, a non-trivial destructor, or a non-trivial copy // assignment operator cannot be a member of a union, nor can an // array of such objects. if (CheckNontrivialField(FD)) Invalid = true; } else if ((*Mem)->isImplicit()) { // Any implicit members are fine. } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { // This is a type that showed up in an // elaborated-type-specifier inside the anonymous struct or // union, but which actually declares a type outside of the // anonymous struct or union. It's okay. } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { if (!MemRecord->isAnonymousStructOrUnion() && MemRecord->getDeclName()) { // Visual C++ allows type definition in anonymous struct or union. if (getLangOpts().MicrosoftExt) Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) << (int)Record->isUnion(); else { // This is a nested type declaration. Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) << (int)Record->isUnion(); Invalid = true; } } else { // This is an anonymous type definition within another anonymous type. // This is a popular extension, provided by Plan9, MSVC and GCC, but // not part of standard C++. Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_anonymous_type) << (int)Record->isUnion(); } } else if (isa<AccessSpecDecl>(*Mem)) { // Any access specifier is fine. } else { // We have something that isn't a non-static data // member. Complain about it. unsigned DK = diag::err_anonymous_record_bad_member; if (isa<TypeDecl>(*Mem)) DK = diag::err_anonymous_record_with_type; else if (isa<FunctionDecl>(*Mem)) DK = diag::err_anonymous_record_with_function; else if (isa<VarDecl>(*Mem)) DK = diag::err_anonymous_record_with_static; // Visual C++ allows type definition in anonymous struct or union. if (getLangOpts().MicrosoftExt && DK == diag::err_anonymous_record_with_type) Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) << (int)Record->isUnion(); else { Diag((*Mem)->getLocation(), DK) << (int)Record->isUnion(); Invalid = true; } } } } if (!Record->isUnion() && !Owner->isRecord()) { Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) << (int)getLangOpts().CPlusPlus; Invalid = true; } // Mock up a declarator. Declarator Dc(DS, Declarator::MemberContext); TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); assert(TInfo && "couldn't build declarator info for anonymous struct/union"); // Create a declaration for this anonymous struct/union. NamedDecl *Anon = 0; if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { Anon = FieldDecl::Create(Context, OwningClass, DS.getLocStart(), Record->getLocation(), /*IdentifierInfo=*/0, Context.getTypeDeclType(Record), TInfo, /*BitWidth=*/0, /*Mutable=*/false, /*InitStyle=*/ICIS_NoInit); Anon->setAccess(AS); if (getLangOpts().CPlusPlus) FieldCollector->Add(cast<FieldDecl>(Anon)); } else { DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(DS); if (SCSpec == DeclSpec::SCS_mutable) { // mutable can only appear on non-static class members, so it's always // an error here Diag(Record->getLocation(), diag::err_mutable_nonmember); Invalid = true; SC = SC_None; } Anon = VarDecl::Create(Context, Owner, DS.getLocStart(), Record->getLocation(), /*IdentifierInfo=*/0, Context.getTypeDeclType(Record), TInfo, SC); // Default-initialize the implicit variable. This initialization will be // trivial in almost all cases, except if a union member has an in-class // initializer: // union { int n = 0; }; ActOnUninitializedDecl(Anon, /*TypeMayContainAuto=*/false); } Anon->setImplicit(); // Add the anonymous struct/union object to the current // context. We'll be referencing this object when we refer to one of // its members. Owner->addDecl(Anon); // Inject the members of the anonymous struct/union into the owning // context and into the identifier resolver chain for name lookup // purposes. SmallVector<NamedDecl*, 2> Chain; Chain.push_back(Anon); if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, Chain, false)) Invalid = true; // Mark this as an anonymous struct/union type. Note that we do not // do this until after we have already checked and injected the // members of this anonymous struct/union type, because otherwise // the members could be injected twice: once by DeclContext when it // builds its lookup table, and once by // InjectAnonymousStructOrUnionMembers. Record->setAnonymousStructOrUnion(true); if (Invalid) Anon->setInvalidDecl(); return Anon; } /// BuildMicrosoftCAnonymousStruct - Handle the declaration of an /// Microsoft C anonymous structure. /// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx /// Example: /// /// struct A { int a; }; /// struct B { struct A; int b; }; /// /// void foo() { /// B var; /// var.a = 3; /// } /// Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, RecordDecl *Record) { // If there is no Record, get the record via the typedef. if (!Record) Record = DS.getRepAsType().get()->getAsStructureType()->getDecl(); // Mock up a declarator. Declarator Dc(DS, Declarator::TypeNameContext); TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); assert(TInfo && "couldn't build declarator info for anonymous struct"); // Create a declaration for this anonymous struct. NamedDecl* Anon = FieldDecl::Create(Context, cast<RecordDecl>(CurContext), DS.getLocStart(), DS.getLocStart(), /*IdentifierInfo=*/0, Context.getTypeDeclType(Record), TInfo, /*BitWidth=*/0, /*Mutable=*/false, /*InitStyle=*/ICIS_NoInit); Anon->setImplicit(); // Add the anonymous struct object to the current context. CurContext->addDecl(Anon); // Inject the members of the anonymous struct into the current // context and into the identifier resolver chain for name lookup // purposes. SmallVector<NamedDecl*, 2> Chain; Chain.push_back(Anon); RecordDecl *RecordDef = Record->getDefinition(); if (!RecordDef || InjectAnonymousStructOrUnionMembers(*this, S, CurContext, RecordDef, AS_none, Chain, true)) Anon->setInvalidDecl(); return Anon; } /// GetNameForDeclarator - Determine the full declaration name for the /// given Declarator. DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { return GetNameFromUnqualifiedId(D.getName()); } /// \brief Retrieves the declaration name from a parsed unqualified-id. DeclarationNameInfo Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { DeclarationNameInfo NameInfo; NameInfo.setLoc(Name.StartLocation); switch (Name.getKind()) { case UnqualifiedId::IK_ImplicitSelfParam: case UnqualifiedId::IK_Identifier: NameInfo.setName(Name.Identifier); NameInfo.setLoc(Name.StartLocation); return NameInfo; case UnqualifiedId::IK_OperatorFunctionId: NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( Name.OperatorFunctionId.Operator)); NameInfo.setLoc(Name.StartLocation); NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc = Name.OperatorFunctionId.SymbolLocations[0]; NameInfo.getInfo().CXXOperatorName.EndOpNameLoc = Name.EndLocation.getRawEncoding(); return NameInfo; case UnqualifiedId::IK_LiteralOperatorId: NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( Name.Identifier)); NameInfo.setLoc(Name.StartLocation); NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); return NameInfo; case UnqualifiedId::IK_ConversionFunctionId: { TypeSourceInfo *TInfo; QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); if (Ty.isNull()) return DeclarationNameInfo(); NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( Context.getCanonicalType(Ty))); NameInfo.setLoc(Name.StartLocation); NameInfo.setNamedTypeInfo(TInfo); return NameInfo; } case UnqualifiedId::IK_ConstructorName: { TypeSourceInfo *TInfo; QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); if (Ty.isNull()) return DeclarationNameInfo(); NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( Context.getCanonicalType(Ty))); NameInfo.setLoc(Name.StartLocation); NameInfo.setNamedTypeInfo(TInfo); return NameInfo; } case UnqualifiedId::IK_ConstructorTemplateId: { // In well-formed code, we can only have a constructor // template-id that refers to the current context, so go there // to find the actual type being constructed. CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) return DeclarationNameInfo(); // Determine the type of the class being constructed. QualType CurClassType = Context.getTypeDeclType(CurClass); // FIXME: Check two things: that the template-id names the same type as // CurClassType, and that the template-id does not occur when the name // was qualified. NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( Context.getCanonicalType(CurClassType))); NameInfo.setLoc(Name.StartLocation); // FIXME: should we retrieve TypeSourceInfo? NameInfo.setNamedTypeInfo(0); return NameInfo; } case UnqualifiedId::IK_DestructorName: { TypeSourceInfo *TInfo; QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); if (Ty.isNull()) return DeclarationNameInfo(); NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( Context.getCanonicalType(Ty))); NameInfo.setLoc(Name.StartLocation); NameInfo.setNamedTypeInfo(TInfo); return NameInfo; } case UnqualifiedId::IK_TemplateId: { TemplateName TName = Name.TemplateId->Template.get(); SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; return Context.getNameForTemplate(TName, TNameLoc); } } // switch (Name.getKind()) llvm_unreachable("Unknown name kind"); } static QualType getCoreType(QualType Ty) { do { if (Ty->isPointerType() || Ty->isReferenceType()) Ty = Ty->getPointeeType(); else if (Ty->isArrayType()) Ty = Ty->castAsArrayTypeUnsafe()->getElementType(); else return Ty.withoutLocalFastQualifiers(); } while (true); } /// hasSimilarParameters - Determine whether the C++ functions Declaration /// and Definition have "nearly" matching parameters. This heuristic is /// used to improve diagnostics in the case where an out-of-line function /// definition doesn't match any declaration within the class or namespace. /// Also sets Params to the list of indices to the parameters that differ /// between the declaration and the definition. If hasSimilarParameters /// returns true and Params is empty, then all of the parameters match. static bool hasSimilarParameters(ASTContext &Context, FunctionDecl *Declaration, FunctionDecl *Definition, SmallVectorImpl<unsigned> &Params) { Params.clear(); if (Declaration->param_size() != Definition->param_size()) return false; for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); // The parameter types are identical if (Context.hasSameType(DefParamTy, DeclParamTy)) continue; QualType DeclParamBaseTy = getCoreType(DeclParamTy); QualType DefParamBaseTy = getCoreType(DefParamTy); const IdentifierInfo *DeclTyName = DeclParamBaseTy.getBaseTypeIdentifier(); const IdentifierInfo *DefTyName = DefParamBaseTy.getBaseTypeIdentifier(); if (Context.hasSameUnqualifiedType(DeclParamBaseTy, DefParamBaseTy) || (DeclTyName && DeclTyName == DefTyName)) Params.push_back(Idx); else // The two parameters aren't even close return false; } return true; } /// NeedsRebuildingInCurrentInstantiation - Checks whether the given /// declarator needs to be rebuilt in the current instantiation. /// Any bits of declarator which appear before the name are valid for /// consideration here. That's specifically the type in the decl spec /// and the base type in any member-pointer chunks. static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, DeclarationName Name) { // The types we specifically need to rebuild are: // - typenames, typeofs, and decltypes // - types which will become injected class names // Of course, we also need to rebuild any type referencing such a // type. It's safest to just say "dependent", but we call out a // few cases here. DeclSpec &DS = D.getMutableDeclSpec(); switch (DS.getTypeSpecType()) { case DeclSpec::TST_typename: case DeclSpec::TST_typeofType: case DeclSpec::TST_underlyingType: case DeclSpec::TST_atomic: { // Grab the type from the parser. TypeSourceInfo *TSI = 0; QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); if (T.isNull() || !T->isDependentType()) break; // Make sure there's a type source info. This isn't really much // of a waste; most dependent types should have type source info // attached already. if (!TSI) TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); // Rebuild the type in the current instantiation. TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); if (!TSI) return true; // Store the new type back in the decl spec. ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); DS.UpdateTypeRep(LocType); break; } case DeclSpec::TST_decltype: case DeclSpec::TST_typeofExpr: { Expr *E = DS.getRepAsExpr(); ExprResult Result = S.RebuildExprInCurrentInstantiation(E); if (Result.isInvalid()) return true; DS.UpdateExprRep(Result.get()); break; } default: // Nothing to do for these decl specs. break; } // It doesn't matter what order we do this in. for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { DeclaratorChunk &Chunk = D.getTypeObject(I); // The only type information in the declarator which can come // before the declaration name is the base type of a member // pointer. if (Chunk.Kind != DeclaratorChunk::MemberPointer) continue; // Rebuild the scope specifier in-place. CXXScopeSpec &SS = Chunk.Mem.Scope(); if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) return true; } return false; } Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { D.setFunctionDefinitionKind(FDK_Declaration); Decl *Dcl = HandleDeclarator(S, D, MultiTemplateParamsArg()); if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer() && Dcl && Dcl->getDeclContext()->isFileContext()) Dcl->setTopLevelDeclInObjCContainer(); return Dcl; } /// DiagnoseClassNameShadow - Implement C++ [class.mem]p13: /// If T is the name of a class, then each of the following shall have a /// name different from T: /// - every static data member of class T; /// - every member function of class T /// - every member of class T that is itself a type; /// \returns true if the declaration name violates these rules. bool Sema::DiagnoseClassNameShadow(DeclContext *DC, DeclarationNameInfo NameInfo) { DeclarationName Name = NameInfo.getName(); if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) if (Record->getIdentifier() && Record->getDeclName() == Name) { Diag(NameInfo.getLoc(), diag::err_member_name_of_class) << Name; return true; } return false; } /// \brief Diagnose a declaration whose declarator-id has the given /// nested-name-specifier. /// /// \param SS The nested-name-specifier of the declarator-id. /// /// \param DC The declaration context to which the nested-name-specifier /// resolves. /// /// \param Name The name of the entity being declared. /// /// \param Loc The location of the name of the entity being declared. /// /// \returns true if we cannot safely recover from this error, false otherwise. bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC, DeclarationName Name, SourceLocation Loc) { DeclContext *Cur = CurContext; while (isa<LinkageSpecDecl>(Cur)) Cur = Cur->getParent(); // C++ [dcl.meaning]p1: // A declarator-id shall not be qualified except for the definition // of a member function (9.3) or static data member (9.4) outside of // its class, the definition or explicit instantiation of a function // or variable member of a namespace outside of its namespace, or the // definition of an explicit specialization outside of its namespace, // or the declaration of a friend function that is a member of // another class or namespace (11.3). [...] // The user provided a superfluous scope specifier that refers back to the // class or namespaces in which the entity is already declared. // // class X { // void X::f(); // }; if (Cur->Equals(DC)) { Diag(Loc, LangOpts.MicrosoftExt? diag::warn_member_extra_qualification : diag::err_member_extra_qualification) << Name << FixItHint::CreateRemoval(SS.getRange()); SS.clear(); return false; } // Check whether the qualifying scope encloses the scope of the original // declaration. if (!Cur->Encloses(DC)) { if (Cur->isRecord()) Diag(Loc, diag::err_member_qualification) << Name << SS.getRange(); else if (isa<TranslationUnitDecl>(DC)) Diag(Loc, diag::err_invalid_declarator_global_scope) << Name << SS.getRange(); else if (isa<FunctionDecl>(Cur)) Diag(Loc, diag::err_invalid_declarator_in_function) << Name << SS.getRange(); else Diag(Loc, diag::err_invalid_declarator_scope) << Name << cast<NamedDecl>(Cur) << cast<NamedDecl>(DC) << SS.getRange(); return true; } if (Cur->isRecord()) { // Cannot qualify members within a class. Diag(Loc, diag::err_member_qualification) << Name << SS.getRange(); SS.clear(); // C++ constructors and destructors with incorrect scopes can break // our AST invariants by having the wrong underlying types. If // that's the case, then drop this declaration entirely. if ((Name.getNameKind() == DeclarationName::CXXConstructorName || Name.getNameKind() == DeclarationName::CXXDestructorName) && !Context.hasSameType(Name.getCXXNameType(), Context.getTypeDeclType(cast<CXXRecordDecl>(Cur)))) return true; return false; } // C++11 [dcl.meaning]p1: // [...] "The nested-name-specifier of the qualified declarator-id shall // not begin with a decltype-specifer" NestedNameSpecifierLoc SpecLoc(SS.getScopeRep(), SS.location_data()); while (SpecLoc.getPrefix()) SpecLoc = SpecLoc.getPrefix(); if (dyn_cast_or_null<DecltypeType>( SpecLoc.getNestedNameSpecifier()->getAsType())) Diag(Loc, diag::err_decltype_in_declarator) << SpecLoc.getTypeLoc().getSourceRange(); return false; } NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D, MultiTemplateParamsArg TemplateParamLists) { // TODO: consider using NameInfo for diagnostic. DeclarationNameInfo NameInfo = GetNameForDeclarator(D); DeclarationName Name = NameInfo.getName(); // All of these full declarators require an identifier. If it doesn't have // one, the ParsedFreeStandingDeclSpec action should be used. if (!Name) { if (!D.isInvalidType()) // Reject this if we think it is valid. Diag(D.getDeclSpec().getLocStart(), diag::err_declarator_need_ident) << D.getDeclSpec().getSourceRange() << D.getSourceRange(); return 0; } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) return 0; // The scope passed in may not be a decl scope. Zip up the scope tree until // we find one that is. while ((S->getFlags() & Scope::DeclScope) == 0 || (S->getFlags() & Scope::TemplateParamScope) != 0) S = S->getParent(); DeclContext *DC = CurContext; if (D.getCXXScopeSpec().isInvalid()) D.setInvalidType(); else if (D.getCXXScopeSpec().isSet()) { if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), UPPC_DeclarationQualifier)) return 0; bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); if (!DC) { // If we could not compute the declaration context, it's because the // declaration context is dependent but does not refer to a class, // class template, or class template partial specialization. Complain // and return early, to avoid the coming semantic disaster. Diag(D.getIdentifierLoc(), diag::err_template_qualified_declarator_no_match) << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() << D.getCXXScopeSpec().getRange(); return 0; } bool IsDependentContext = DC->isDependentContext(); if (!IsDependentContext && RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) return 0; if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { Diag(D.getIdentifierLoc(), diag::err_member_def_undefined_record) << Name << DC << D.getCXXScopeSpec().getRange(); D.setInvalidType(); } else if (!D.getDeclSpec().isFriendSpecified()) { if (diagnoseQualifiedDeclaration(D.getCXXScopeSpec(), DC, Name, D.getIdentifierLoc())) { if (DC->isRecord()) return 0; D.setInvalidType(); } } // Check whether we need to rebuild the type of the given // declaration in the current instantiation. if (EnteringContext && IsDependentContext && TemplateParamLists.size() != 0) { ContextRAII SavedContext(*this, DC); if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) D.setInvalidType(); } } if (DiagnoseClassNameShadow(DC, NameInfo)) // If this is a typedef, we'll end up spewing multiple diagnostics. // Just return early; it's safer. if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) return 0; TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); QualType R = TInfo->getType(); if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, UPPC_DeclarationType)) D.setInvalidType(); LookupResult Previous(*this, NameInfo, LookupOrdinaryName, ForRedeclaration); // See if this is a redefinition of a variable in the same scope. if (!D.getCXXScopeSpec().isSet()) { bool IsLinkageLookup = false; // If the declaration we're planning to build will be a function // or object with linkage, then look for another declaration with // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) /* Do nothing*/; else if (R->isFunctionType()) { if (CurContext->isFunctionOrMethod() || D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) IsLinkageLookup = true; } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) IsLinkageLookup = true; else if (CurContext->getRedeclContext()->isTranslationUnit() && D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) IsLinkageLookup = true; if (IsLinkageLookup) Previous.clear(LookupRedeclarationWithLinkage); LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); } else { // Something like "int foo::x;" LookupQualifiedName(Previous, DC); // C++ [dcl.meaning]p1: // When the declarator-id is qualified, the declaration shall refer to a // previously declared member of the class or namespace to which the // qualifier refers (or, in the case of a namespace, of an element of the // inline namespace set of that namespace (7.3.1)) or to a specialization // thereof; [...] // // Note that we already checked the context above, and that we do not have // enough information to make sure that Previous contains the declaration // we want to match. For example, given: // // class X { // void f(); // void f(float); // }; // // void X::f(int) { } // ill-formed // // In this case, Previous will point to the overload set // containing the two f's declared in X, but neither of them // matches. // C++ [dcl.meaning]p1: // [...] the member shall not merely have been introduced by a // using-declaration in the scope of the class or namespace nominated by // the nested-name-specifier of the declarator-id. RemoveUsingDecls(Previous); } if (Previous.isSingleResult() && Previous.getFoundDecl()->isTemplateParameter()) { // Maybe we will complain about the shadowed template parameter. if (!D.isInvalidType()) DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), Previous.getFoundDecl()); // Just pretend that we didn't see the previous declaration. Previous.clear(); } // In C++, the previous declaration we find might be a tag type // (class or enum). In this case, the new declaration will hide the // tag type. Note that this does does not apply if we're declaring a // typedef (C++ [dcl.typedef]p4). if (Previous.isSingleTagDecl() && D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) Previous.clear(); // Check that there are no default arguments other than in the parameters // of a function declaration (C++ only). if (getLangOpts().CPlusPlus) CheckExtraCXXDefaultArguments(D); NamedDecl *New; bool AddToScope = true; if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { if (TemplateParamLists.size()) { Diag(D.getIdentifierLoc(), diag::err_template_typedef); return 0; } New = ActOnTypedefDeclarator(S, D, DC, TInfo, Previous); } else if (R->isFunctionType()) { New = ActOnFunctionDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists, AddToScope); } else { New = ActOnVariableDeclarator(S, D, DC, TInfo, Previous, TemplateParamLists, AddToScope); } if (New == 0) return 0; // If this has an identifier and is not an invalid redeclaration or // function template specialization, add it to the scope stack. if (New->getDeclName() && AddToScope && !(D.isRedeclaration() && New->isInvalidDecl())) PushOnScopeChains(New, S); return New; } /// Helper method to turn variable array types into constant array /// types in certain situations which would otherwise be errors (for /// GCC compatibility). static QualType TryToFixInvalidVariablyModifiedType(QualType T, ASTContext &Context, bool &SizeIsNegative, llvm::APSInt &Oversized) { // This method tries to turn a variable array into a constant // array even when the size isn't an ICE. This is necessary // for compatibility with code that depends on gcc's buggy // constant expression folding, like struct {char x[(int)(char*)2];} SizeIsNegative = false; Oversized = 0; if (T->isDependentType()) return QualType(); QualifierCollector Qs; const Type *Ty = Qs.strip(T); if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { QualType Pointee = PTy->getPointeeType(); QualType FixedType = TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, Oversized); if (FixedType.isNull()) return FixedType; FixedType = Context.getPointerType(FixedType); return Qs.apply(Context, FixedType); } if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { QualType Inner = PTy->getInnerType(); QualType FixedType = TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative, Oversized); if (FixedType.isNull()) return FixedType; FixedType = Context.getParenType(FixedType); return Qs.apply(Context, FixedType); } const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); if (!VLATy) return QualType(); // FIXME: We should probably handle this case if (VLATy->getElementType()->isVariablyModifiedType()) return QualType(); llvm::APSInt Res; if (!VLATy->getSizeExpr() || !VLATy->getSizeExpr()->EvaluateAsInt(Res, Context)) return QualType(); // Check whether the array size is negative. if (Res.isSigned() && Res.isNegative()) { SizeIsNegative = true; return QualType(); } // Check whether the array is too large to be addressed. unsigned ActiveSizeBits = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), Res); if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { Oversized = Res; return QualType(); } return Context.getConstantArrayType(VLATy->getElementType(), Res, ArrayType::Normal, 0); } static void FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) { if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) { PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>(); FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(), DstPTL.getPointeeLoc()); DstPTL.setStarLoc(SrcPTL.getStarLoc()); return; } if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) { ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>(); FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(), DstPTL.getInnerLoc()); DstPTL.setLParenLoc(SrcPTL.getLParenLoc()); DstPTL.setRParenLoc(SrcPTL.getRParenLoc()); return; } ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>(); ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>(); TypeLoc SrcElemTL = SrcATL.getElementLoc(); TypeLoc DstElemTL = DstATL.getElementLoc(); DstElemTL.initializeFullCopy(SrcElemTL); DstATL.setLBracketLoc(SrcATL.getLBracketLoc()); DstATL.setSizeExpr(SrcATL.getSizeExpr()); DstATL.setRBracketLoc(SrcATL.getRBracketLoc()); } /// Helper method to turn variable array types into constant array /// types in certain situations which would otherwise be errors (for /// GCC compatibility). static TypeSourceInfo* TryToFixInvalidVariablyModifiedTypeSourceInfo(TypeSourceInfo *TInfo, ASTContext &Context, bool &SizeIsNegative, llvm::APSInt &Oversized) { QualType FixedTy = TryToFixInvalidVariablyModifiedType(TInfo->getType(), Context, SizeIsNegative, Oversized); if (FixedTy.isNull()) return 0; TypeSourceInfo *FixedTInfo = Context.getTrivialTypeSourceInfo(FixedTy); FixInvalidVariablyModifiedTypeLoc(TInfo->getTypeLoc(), FixedTInfo->getTypeLoc()); return FixedTInfo; } /// \brief Register the given locally-scoped extern "C" declaration so /// that it can be found later for redeclarations. We include any extern "C" /// declaration that is not visible in the translation unit here, not just /// function-scope declarations. void Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S) { if (!getLangOpts().CPlusPlus && ND->getLexicalDeclContext()->getRedeclContext()->isTranslationUnit()) // Don't need to track declarations in the TU in C. return; // Note that we have a locally-scoped external with this name. // FIXME: There can be multiple such declarations if they are functions marked // __attribute__((overloadable)) declared in function scope in C. LocallyScopedExternCDecls[ND->getDeclName()] = ND; } NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) { if (ExternalSource) { // Load locally-scoped external decls from the external source. // FIXME: This is inefficient. Maybe add a DeclContext for extern "C" decls? SmallVector<NamedDecl *, 4> Decls; ExternalSource->ReadLocallyScopedExternCDecls(Decls); for (unsigned I = 0, N = Decls.size(); I != N; ++I) { llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos = LocallyScopedExternCDecls.find(Decls[I]->getDeclName()); if (Pos == LocallyScopedExternCDecls.end()) LocallyScopedExternCDecls[Decls[I]->getDeclName()] = Decls[I]; } } NamedDecl *D = LocallyScopedExternCDecls.lookup(Name); return D ? cast<NamedDecl>(D->getMostRecentDecl()) : 0; } /// \brief Diagnose function specifiers on a declaration of an identifier that /// does not identify a function. void Sema::DiagnoseFunctionSpecifiers(const DeclSpec &DS) { // FIXME: We should probably indicate the identifier in question to avoid // confusion for constructs like "inline int a(), b;" if (DS.isInlineSpecified()) Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function); if (DS.isVirtualSpecified()) Diag(DS.getVirtualSpecLoc(), diag::err_virtual_non_function); if (DS.isExplicitSpecified()) Diag(DS.getExplicitSpecLoc(), diag::err_explicit_non_function); if (DS.isNoreturnSpecified()) Diag(DS.getNoreturnSpecLoc(), diag::err_noreturn_non_function); } NamedDecl* Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, TypeSourceInfo *TInfo, LookupResult &Previous) { // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). if (D.getCXXScopeSpec().isSet()) { Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) << D.getCXXScopeSpec().getRange(); D.setInvalidType(); // Pretend we didn't see the scope specifier. DC = CurContext; Previous.clear(); } DiagnoseFunctionSpecifiers(D.getDeclSpec()); if (D.getDeclSpec().isConstexprSpecified()) Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr) << 1; if (D.getName().Kind != UnqualifiedId::IK_Identifier) { Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) << D.getName().getSourceRange(); return 0; } TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo); if (!NewTD) return 0; // Handle attributes prior to checking for duplicates in MergeVarDecl ProcessDeclAttributes(S, NewTD, D); CheckTypedefForVariablyModifiedType(S, NewTD); bool Redeclaration = D.isRedeclaration(); NamedDecl *ND = ActOnTypedefNameDecl(S, DC, NewTD, Previous, Redeclaration); D.setRedeclaration(Redeclaration); return ND; } void Sema::CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *NewTD) { // C99 6.7.7p2: If a typedef name specifies a variably modified type // then it shall have block scope. // Note that variably modified types must be fixed before merging the decl so // that redeclarations will match. TypeSourceInfo *TInfo = NewTD->getTypeSourceInfo(); QualType T = TInfo->getType(); if (T->isVariablyModifiedType()) { getCurFunction()->setHasBranchProtectedScope(); if (S->getFnParent() == 0) { bool SizeIsNegative; llvm::APSInt Oversized; TypeSourceInfo *FixedTInfo = TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context, SizeIsNegative, Oversized); if (FixedTInfo) { Diag(NewTD->getLocation(), diag::warn_illegal_constant_array_size); NewTD->setTypeSourceInfo(FixedTInfo); } else { if (SizeIsNegative) Diag(NewTD->getLocation(), diag::err_typecheck_negative_array_size); else if (T->isVariableArrayType()) Diag(NewTD->getLocation(), diag::err_vla_decl_in_file_scope); else if (Oversized.getBoolValue()) Diag(NewTD->getLocation(), diag::err_array_too_large) << Oversized.toString(10); else Diag(NewTD->getLocation(), diag::err_vm_decl_in_file_scope); NewTD->setInvalidDecl(); } } } } /// ActOnTypedefNameDecl - Perform semantic checking for a declaration which /// declares a typedef-name, either using the 'typedef' type specifier or via /// a C++0x [dcl.typedef]p2 alias-declaration: 'using T = A;'. NamedDecl* Sema::ActOnTypedefNameDecl(Scope *S, DeclContext *DC, TypedefNameDecl *NewTD, LookupResult &Previous, bool &Redeclaration) { // Merge the decl with the existing one if appropriate. If the decl is // in an outer scope, it isn't the same thing. FilterLookupForScope(Previous, DC, S, /*ConsiderLinkage*/ false, /*ExplicitInstantiationOrSpecialization=*/false); filterNonConflictingPreviousDecls(Context, NewTD, Previous); if (!Previous.empty()) { Redeclaration = true; MergeTypedefNameDecl(NewTD, Previous); } // If this is the C FILE type, notify the AST context. if (IdentifierInfo *II = NewTD->getIdentifier()) if (!NewTD->isInvalidDecl() && NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { if (II->isStr("FILE")) Context.setFILEDecl(NewTD); else if (II->isStr("jmp_buf")) Context.setjmp_bufDecl(NewTD); else if (II->isStr("sigjmp_buf")) Context.setsigjmp_bufDecl(NewTD); else if (II->isStr("ucontext_t")) Context.setucontext_tDecl(NewTD); } return NewTD; } /// \brief Determines whether the given declaration is an out-of-scope /// previous declaration. /// /// This routine should be invoked when name lookup has found a /// previous declaration (PrevDecl) that is not in the scope where a /// new declaration by the same name is being introduced. If the new /// declaration occurs in a local scope, previous declarations with /// linkage may still be considered previous declarations (C99 /// 6.2.2p4-5, C++ [basic.link]p6). /// /// \param PrevDecl the previous declaration found by name /// lookup /// /// \param DC the context in which the new declaration is being /// declared. /// /// \returns true if PrevDecl is an out-of-scope previous declaration /// for a new delcaration with the same name. static bool isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, ASTContext &Context) { if (!PrevDecl) return false; if (!PrevDecl->hasLinkage()) return false; if (Context.getLangOpts().CPlusPlus) { // C++ [basic.link]p6: // If there is a visible declaration of an entity with linkage // having the same name and type, ignoring entities declared // outside the innermost enclosing namespace scope, the block // scope declaration declares that same entity and receives the // linkage of the previous declaration. DeclContext *OuterContext = DC->getRedeclContext(); if (!OuterContext->isFunctionOrMethod()) // This rule only applies to block-scope declarations. return false; DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); if (PrevOuterContext->isRecord()) // We found a member function: ignore it. return false; // Find the innermost enclosing namespace for the new and // previous declarations. OuterContext = OuterContext->getEnclosingNamespaceContext(); PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); // The previous declaration is in a different namespace, so it // isn't the same function. if (!OuterContext->Equals(PrevOuterContext)) return false; } return true; } static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { CXXScopeSpec &SS = D.getCXXScopeSpec(); if (!SS.isSet()) return; DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext())); } bool Sema::inferObjCARCLifetime(ValueDecl *decl) { QualType type = decl->getType(); Qualifiers::ObjCLifetime lifetime = type.getObjCLifetime(); if (lifetime == Qualifiers::OCL_Autoreleasing) { // Various kinds of declaration aren't allowed to be __autoreleasing. unsigned kind = -1U; if (VarDecl *var = dyn_cast<VarDecl>(decl)) { if (var->hasAttr<BlocksAttr>()) kind = 0; // __block else if (!var->hasLocalStorage()) kind = 1; // global } else if (isa<ObjCIvarDecl>(decl)) { kind = 3; // ivar } else if (isa<FieldDecl>(decl)) { kind = 2; // field } if (kind != -1U) { Diag(decl->getLocation(), diag::err_arc_autoreleasing_var) << kind; } } else if (lifetime == Qualifiers::OCL_None) { // Try to infer lifetime. if (!type->isObjCLifetimeType()) return false; lifetime = type->getObjCARCImplicitLifetime(); type = Context.getLifetimeQualifiedType(type, lifetime); decl->setType(type); } if (VarDecl *var = dyn_cast<VarDecl>(decl)) { // Thread-local variables cannot have lifetime. if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone && var->getTLSKind()) { Diag(var->getLocation(), diag::err_arc_thread_ownership) << var->getType(); return true; } } return false; } static void checkAttributesAfterMerging(Sema &S, NamedDecl &ND) { // 'weak' only applies to declarations with external linkage. if (WeakAttr *Attr = ND.getAttr<WeakAttr>()) { if (!ND.isExternallyVisible()) { S.Diag(Attr->getLocation(), diag::err_attribute_weak_static); ND.dropAttr<WeakAttr>(); } } if (WeakRefAttr *Attr = ND.getAttr<WeakRefAttr>()) { if (ND.isExternallyVisible()) { S.Diag(Attr->getLocation(), diag::err_attribute_weakref_not_static); ND.dropAttr<WeakRefAttr>(); } } // 'selectany' only applies to externally visible varable declarations. // It does not apply to functions. if (SelectAnyAttr *Attr = ND.getAttr<SelectAnyAttr>()) { if (isa<FunctionDecl>(ND) || !ND.isExternallyVisible()) { S.Diag(Attr->getLocation(), diag::err_attribute_selectany_non_extern_data); ND.dropAttr<SelectAnyAttr>(); } } } /// Given that we are within the definition of the given function, /// will that definition behave like C99's 'inline', where the /// definition is discarded except for optimization purposes? static bool isFunctionDefinitionDiscarded(Sema &S, FunctionDecl *FD) { // Try to avoid calling GetGVALinkageForFunction. // All cases of this require the 'inline' keyword. if (!FD->isInlined()) return false; // This is only possible in C++ with the gnu_inline attribute. if (S.getLangOpts().CPlusPlus && !FD->hasAttr<GNUInlineAttr>()) return false; // Okay, go ahead and call the relatively-more-expensive function. #ifndef NDEBUG // AST quite reasonably asserts that it's working on a function // definition. We don't really have a way to tell it that we're // currently defining the function, so just lie to it in +Asserts // builds. This is an awful hack. FD->setLazyBody(1); #endif bool isC99Inline = (S.Context.GetGVALinkageForFunction(FD) == GVA_C99Inline); #ifndef NDEBUG FD->setLazyBody(0); #endif return isC99Inline; } /// Determine whether a variable is extern "C" prior to attaching /// an initializer. We can't just call isExternC() here, because that /// will also compute and cache whether the declaration is externally /// visible, which might change when we attach the initializer. /// /// This can only be used if the declaration is known to not be a /// redeclaration of an internal linkage declaration. /// /// For instance: /// /// auto x = []{}; /// /// Attaching the initializer here makes this declaration not externally /// visible, because its type has internal linkage. /// /// FIXME: This is a hack. template<typename T> static bool isIncompleteDeclExternC(Sema &S, const T *D) { if (S.getLangOpts().CPlusPlus) { // In C++, the overloadable attribute negates the effects of extern "C". if (!D->isInExternCContext() || D->template hasAttr<OverloadableAttr>()) return false; } return D->isExternC(); } static bool shouldConsiderLinkage(const VarDecl *VD) { const DeclContext *DC = VD->getDeclContext()->getRedeclContext(); if (DC->isFunctionOrMethod()) return VD->hasExternalStorage(); if (DC->isFileContext()) return true; if (DC->isRecord()) return false; llvm_unreachable("Unexpected context"); } static bool shouldConsiderLinkage(const FunctionDecl *FD) { const DeclContext *DC = FD->getDeclContext()->getRedeclContext(); if (DC->isFileContext() || DC->isFunctionOrMethod()) return true; if (DC->isRecord()) return false; llvm_unreachable("Unexpected context"); } bool Sema::HandleVariableRedeclaration(Decl *D, CXXScopeSpec &SS) { // If this is a redeclaration of a variable template or a forward // declaration of a variable template partial specialization // with nested name specifier, complain. if (D && SS.isNotEmpty() && (isa<VarTemplateDecl>(D) || isa<VarTemplatePartialSpecializationDecl>(D))) { Diag(SS.getBeginLoc(), diag::err_forward_var_nested_name_specifier) << isa<VarTemplatePartialSpecializationDecl>(D) << SS.getRange(); return true; } return false; } NamedDecl * Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, TypeSourceInfo *TInfo, LookupResult &Previous, MultiTemplateParamsArg TemplateParamLists, bool &AddToScope) { QualType R = TInfo->getType(); DeclarationName Name = GetNameForDeclarator(D).getName(); DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(D.getDeclSpec()); if (getLangOpts().OpenCL && !getOpenCLOptions().cl_khr_fp16) { // OpenCL v1.2 s6.1.1.1: reject declaring variables of the half and // half array type (unless the cl_khr_fp16 extension is enabled). if (Context.getBaseElementType(R)->isHalfType()) { Diag(D.getIdentifierLoc(), diag::err_opencl_half_declaration) << R; D.setInvalidType(); } } if (SCSpec == DeclSpec::SCS_mutable) { // mutable can only appear on non-static class members, so it's always // an error here Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); D.setInvalidType(); SC = SC_None; } if (getLangOpts().CPlusPlus11 && SCSpec == DeclSpec::SCS_register && !D.getAsmLabel() && !getSourceManager().isInSystemMacro( D.getDeclSpec().getStorageClassSpecLoc())) { // In C++11, the 'register' storage class specifier is deprecated. // Suppress the warning in system macros, it's used in macros in some // popular C system headers, such as in glibc's htonl() macro. Diag(D.getDeclSpec().getStorageClassSpecLoc(), diag::warn_deprecated_register) << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); } IdentifierInfo *II = Name.getAsIdentifierInfo(); if (!II) { Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) << Name; return 0; } DiagnoseFunctionSpecifiers(D.getDeclSpec()); if (!DC->isRecord() && S->getFnParent() == 0) { // C99 6.9p2: The storage-class specifiers auto and register shall not // appear in the declaration specifiers in an external declaration. if (SC == SC_Auto || SC == SC_Register) { // If this is a register variable with an asm label specified, then this // is a GNU extension. if (SC == SC_Register && D.getAsmLabel()) Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); else Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); D.setInvalidType(); } } if (getLangOpts().OpenCL) { // Set up the special work-group-local storage class for variables in the // OpenCL __local address space. if (R.getAddressSpace() == LangAS::opencl_local) { SC = SC_OpenCLWorkGroupLocal; } // OpenCL v1.2 s6.9.b p4: // The sampler type cannot be used with the __local and __global address // space qualifiers. if (R->isSamplerT() && (R.getAddressSpace() == LangAS::opencl_local || R.getAddressSpace() == LangAS::opencl_global)) { Diag(D.getIdentifierLoc(), diag::err_wrong_sampler_addressspace); } // OpenCL 1.2 spec, p6.9 r: // The event type cannot be used to declare a program scope variable. // The event type cannot be used with the __local, __constant and __global // address space qualifiers. if (R->isEventT()) { if (S->getParent() == 0) { Diag(D.getLocStart(), diag::err_event_t_global_var); D.setInvalidType(); } if (R.getAddressSpace()) { Diag(D.getLocStart(), diag::err_event_t_addr_space_qual); D.setInvalidType(); } } } bool IsExplicitSpecialization = false; bool IsVariableTemplateSpecialization = false; bool IsPartialSpecialization = false; bool Invalid = false; // TODO: Can we remove this (error-prone)? TemplateParameterList *TemplateParams = 0; VarTemplateDecl *PrevVarTemplate = 0; VarDecl *NewVD; if (!getLangOpts().CPlusPlus) { NewVD = VarDecl::Create(Context, DC, D.getLocStart(), D.getIdentifierLoc(), II, R, TInfo, SC); if (D.isInvalidType()) NewVD->setInvalidDecl(); } else { if (DC->isRecord() && !CurContext->isRecord()) { // This is an out-of-line definition of a static data member. switch (SC) { case SC_None: break; case SC_Static: Diag(D.getDeclSpec().getStorageClassSpecLoc(), diag::err_static_out_of_line) << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); break; case SC_Auto: case SC_Register: case SC_Extern: // [dcl.stc] p2: The auto or register specifiers shall be applied only // to names of variables declared in a block or to function parameters. // [dcl.stc] p6: The extern specifier cannot be used in the declaration // of class members Diag(D.getDeclSpec().getStorageClassSpecLoc(), diag::err_storage_class_for_static_member) << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); break; case SC_PrivateExtern: llvm_unreachable("C storage class in c++!"); case SC_OpenCLWorkGroupLocal: llvm_unreachable("OpenCL storage class in c++!"); } } if (SC == SC_Static && CurContext->isRecord()) { if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { if (RD->isLocalClass()) Diag(D.getIdentifierLoc(), diag::err_static_data_member_not_allowed_in_local_class) << Name << RD->getDeclName(); // C++98 [class.union]p1: If a union contains a static data member, // the program is ill-formed. C++11 drops this restriction. if (RD->isUnion()) Diag(D.getIdentifierLoc(), getLangOpts().CPlusPlus11 ? diag::warn_cxx98_compat_static_data_member_in_union : diag::ext_static_data_member_in_union) << Name; // We conservatively disallow static data members in anonymous structs. else if (!RD->getDeclName()) Diag(D.getIdentifierLoc(), diag::err_static_data_member_not_allowed_in_anon_struct) << Name << RD->isUnion(); } } NamedDecl *PrevDecl = 0; if (Previous.begin() != Previous.end()) PrevDecl = (*Previous.begin())->getUnderlyingDecl(); PrevVarTemplate = dyn_cast_or_null<VarTemplateDecl>(PrevDecl); // Match up the template parameter lists with the scope specifier, then // determine whether we have a template or a template specialization. TemplateParams = MatchTemplateParametersToScopeSpecifier( D.getDeclSpec().getLocStart(), D.getIdentifierLoc(), D.getCXXScopeSpec(), TemplateParamLists, /*never a friend*/ false, IsExplicitSpecialization, Invalid); if (TemplateParams) { if (!TemplateParams->size() && D.getName().getKind() != UnqualifiedId::IK_TemplateId) { // There is an extraneous 'template<>' for this variable. Complain // about it, but allow the declaration of the variable. Diag(TemplateParams->getTemplateLoc(), diag::err_template_variable_noparams) << II << SourceRange(TemplateParams->getTemplateLoc(), TemplateParams->getRAngleLoc()); } else { // Only C++1y supports variable templates (N3651). Diag(D.getIdentifierLoc(), getLangOpts().CPlusPlus1y ? diag::warn_cxx11_compat_variable_template : diag::ext_variable_template); if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { // This is an explicit specialization or a partial specialization. // Check that we can declare a specialization here IsVariableTemplateSpecialization = true; IsPartialSpecialization = TemplateParams->size() > 0; } else { // if (TemplateParams->size() > 0) // This is a template declaration. // Check that we can declare a template here. if (CheckTemplateDeclScope(S, TemplateParams)) return 0; // If there is a previous declaration with the same name, check // whether this is a valid redeclaration. if (PrevDecl && !isDeclInScope(PrevDecl, DC, S)) PrevDecl = PrevVarTemplate = 0; if (PrevVarTemplate) { // Ensure that the template parameter lists are compatible. if (!TemplateParameterListsAreEqual( TemplateParams, PrevVarTemplate->getTemplateParameters(), /*Complain=*/true, TPL_TemplateMatch)) return 0; } else if (PrevDecl && PrevDecl->isTemplateParameter()) { // Maybe we will complain about the shadowed template parameter. DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); // Just pretend that we didn't see the previous declaration. PrevDecl = 0; } else if (PrevDecl) { // C++ [temp]p5: // ... a template name declared in namespace scope or in class // scope shall be unique in that scope. Diag(D.getIdentifierLoc(), diag::err_redefinition_different_kind) << Name; Diag(PrevDecl->getLocation(), diag::note_previous_definition); return 0; } // Check the template parameter list of this declaration, possibly // merging in the template parameter list from the previous variable // template declaration. if (CheckTemplateParameterList( TemplateParams, PrevVarTemplate ? PrevVarTemplate->getTemplateParameters() : 0, (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() && DC->isDependentContext()) ? TPC_ClassTemplateMember : TPC_VarTemplate)) Invalid = true; if (D.getCXXScopeSpec().isSet()) { // If the name of the template was qualified, we must be defining // the template out-of-line. if (!D.getCXXScopeSpec().isInvalid() && !Invalid && !PrevVarTemplate) { Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) << Name << DC << D.getCXXScopeSpec().getRange(); Invalid = true; } } } } } else if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { TemplateIdAnnotation *TemplateId = D.getName().TemplateId; // We have encountered something that the user meant to be a // specialization (because it has explicitly-specified template // arguments) but that was not introduced with a "template<>" (or had // too few of them). // FIXME: Differentiate between attempts for explicit instantiations // (starting with "template") and the rest. Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) << FixItHint::CreateInsertion(D.getDeclSpec().getLocStart(), "template<> "); IsVariableTemplateSpecialization = true; } if (IsVariableTemplateSpecialization) { if (!PrevVarTemplate) { Diag(D.getIdentifierLoc(), diag::err_var_spec_no_template) << IsPartialSpecialization; return 0; } SourceLocation TemplateKWLoc = TemplateParamLists.size() > 0 ? TemplateParamLists[0]->getTemplateLoc() : SourceLocation(); DeclResult Res = ActOnVarTemplateSpecialization( S, PrevVarTemplate, D, TInfo, TemplateKWLoc, TemplateParams, SC, IsPartialSpecialization); if (Res.isInvalid()) return 0; NewVD = cast<VarDecl>(Res.get()); AddToScope = false; } else NewVD = VarDecl::Create(Context, DC, D.getLocStart(), D.getIdentifierLoc(), II, R, TInfo, SC); // If this decl has an auto type in need of deduction, make a note of the // Decl so we can diagnose uses of it in its own initializer. if (D.getDeclSpec().containsPlaceholderType() && R->getContainedAutoType()) ParsingInitForAutoVars.insert(NewVD); if (D.isInvalidType() || Invalid) NewVD->setInvalidDecl(); SetNestedNameSpecifier(NewVD, D); // FIXME: Do we need D.getCXXScopeSpec().isSet()? if (TemplateParams && TemplateParamLists.size() > 1 && (!IsVariableTemplateSpecialization || D.getCXXScopeSpec().isSet())) { NewVD->setTemplateParameterListsInfo( Context, TemplateParamLists.size() - 1, TemplateParamLists.data()); } else if (IsVariableTemplateSpecialization || (!TemplateParams && TemplateParamLists.size() > 0 && (D.getCXXScopeSpec().isSet()))) { NewVD->setTemplateParameterListsInfo(Context, TemplateParamLists.size(), TemplateParamLists.data()); } if (D.getDeclSpec().isConstexprSpecified()) NewVD->setConstexpr(true); } // Set the lexical context. If the declarator has a C++ scope specifier, the // lexical context will be different from the semantic context. NewVD->setLexicalDeclContext(CurContext); if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) { if (NewVD->hasLocalStorage()) { // C++11 [dcl.stc]p4: // When thread_local is applied to a variable of block scope the // storage-class-specifier static is implied if it does not appear // explicitly. // Core issue: 'static' is not implied if the variable is declared // 'extern'. if (SCSpec == DeclSpec::SCS_unspecified && TSCS == DeclSpec::TSCS_thread_local && DC->isFunctionOrMethod()) NewVD->setTSCSpec(TSCS); else Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(), diag::err_thread_non_global) << DeclSpec::getSpecifierName(TSCS); } else if (!Context.getTargetInfo().isTLSSupported()) Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(), diag::err_thread_unsupported); else NewVD->setTSCSpec(TSCS); } // C99 6.7.4p3 // An inline definition of a function with external linkage shall // not contain a definition of a modifiable object with static or // thread storage duration... // We only apply this when the function is required to be defined // elsewhere, i.e. when the function is not 'extern inline'. Note // that a local variable with thread storage duration still has to // be marked 'static'. Also note that it's possible to get these // semantics in C++ using __attribute__((gnu_inline)). if (SC == SC_Static && S->getFnParent() != 0 && !NewVD->getType().isConstQualified()) { FunctionDecl *CurFD = getCurFunctionDecl(); if (CurFD && isFunctionDefinitionDiscarded(*this, CurFD)) { Diag(D.getDeclSpec().getStorageClassSpecLoc(), diag::warn_static_local_in_extern_inline); MaybeSuggestAddingStaticToDecl(CurFD); } } if (D.getDeclSpec().isModulePrivateSpecified()) { if (IsVariableTemplateSpecialization) Diag(NewVD->getLocation(), diag::err_module_private_specialization) << (IsPartialSpecialization ? 1 : 0) << FixItHint::CreateRemoval( D.getDeclSpec().getModulePrivateSpecLoc()); else if (IsExplicitSpecialization) Diag(NewVD->getLocation(), diag::err_module_private_specialization) << 2 << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc()); else if (NewVD->hasLocalStorage()) Diag(NewVD->getLocation(), diag::err_module_private_local) << 0 << NewVD->getDeclName() << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc()) << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc()); else NewVD->setModulePrivate(); } // Handle attributes prior to checking for duplicates in MergeVarDecl ProcessDeclAttributes(S, NewVD, D); if (NewVD->hasAttrs()) CheckAlignasUnderalignment(NewVD); if (getLangOpts().CUDA) { // CUDA B.2.5: "__shared__ and __constant__ variables have implied static // storage [duration]." if (SC == SC_None && S->getFnParent() != 0 && (NewVD->hasAttr<CUDASharedAttr>() || NewVD->hasAttr<CUDAConstantAttr>())) { NewVD->setStorageClass(SC_Static); } } // In auto-retain/release, infer strong retension for variables of // retainable type. if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewVD)) NewVD->setInvalidDecl(); // Handle GNU asm-label extension (encoded as an attribute). if (Expr *E = (Expr*)D.getAsmLabel()) { // The parser guarantees this is a string. StringLiteral *SE = cast<StringLiteral>(E); StringRef Label = SE->getString(); if (S->getFnParent() != 0) { switch (SC) { case SC_None: case SC_Auto: Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label; break; case SC_Register: if (!Context.getTargetInfo().isValidGCCRegisterName(Label)) Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label; break; case SC_Static: case SC_Extern: case SC_PrivateExtern: case SC_OpenCLWorkGroupLocal: break; } } NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, Label)); } else if (!ExtnameUndeclaredIdentifiers.empty()) { llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I = ExtnameUndeclaredIdentifiers.find(NewVD->getIdentifier()); if (I != ExtnameUndeclaredIdentifiers.end()) { NewVD->addAttr(I->second); ExtnameUndeclaredIdentifiers.erase(I); } } // Diagnose shadowed variables before filtering for scope. // FIXME: Special treatment for static variable template members (?). if (!D.getCXXScopeSpec().isSet()) CheckShadow(S, NewVD, Previous); // Don't consider existing declarations that are in a different // scope and are out-of-semantic-context declarations (if the new // declaration has linkage). FilterLookupForScope( Previous, DC, S, shouldConsiderLinkage(NewVD), IsExplicitSpecialization || IsVariableTemplateSpecialization); if (!getLangOpts().CPlusPlus) { D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous)); } else { // Merge the decl with the existing one if appropriate. if (!Previous.empty()) { if (Previous.isSingleResult() && isa<FieldDecl>(Previous.getFoundDecl()) && D.getCXXScopeSpec().isSet()) { // The user tried to define a non-static data member // out-of-line (C++ [dcl.meaning]p1). Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) << D.getCXXScopeSpec().getRange(); Previous.clear(); NewVD->setInvalidDecl(); } } else if (D.getCXXScopeSpec().isSet()) { // No previous declaration in the qualifying scope. Diag(D.getIdentifierLoc(), diag::err_no_member) << Name << computeDeclContext(D.getCXXScopeSpec(), true) << D.getCXXScopeSpec().getRange(); NewVD->setInvalidDecl(); } if (!IsVariableTemplateSpecialization) { if (PrevVarTemplate) { LookupResult PrevDecl(*this, GetNameForDeclarator(D), LookupOrdinaryName, ForRedeclaration); PrevDecl.addDecl(PrevVarTemplate->getTemplatedDecl()); D.setRedeclaration(CheckVariableDeclaration(NewVD, PrevDecl)); } else D.setRedeclaration(CheckVariableDeclaration(NewVD, Previous)); } // This is an explicit specialization of a static data member. Check it. // FIXME: Special treatment for static variable template members (?). if (IsExplicitSpecialization && !NewVD->isInvalidDecl() && CheckMemberSpecialization(NewVD, Previous)) NewVD->setInvalidDecl(); } ProcessPragmaWeak(S, NewVD); checkAttributesAfterMerging(*this, *NewVD); // If this is the first declaration of an extern C variable, update // the map of such variables. if (!NewVD->getPreviousDecl() && !NewVD->isInvalidDecl() && isIncompleteDeclExternC(*this, NewVD)) RegisterLocallyScopedExternCDecl(NewVD, S); if (NewVD->isStaticLocal()) { Decl *ManglingContextDecl; if (MangleNumberingContext *MCtx = getCurrentMangleNumberContext(NewVD->getDeclContext(), ManglingContextDecl)) { Context.setManglingNumber(NewVD, MCtx->getManglingNumber(NewVD)); } } // If this is not a variable template, return it now if (!TemplateParams || IsVariableTemplateSpecialization) return NewVD; // If this is supposed to be a variable template, create it as such. VarTemplateDecl *NewTemplate = VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name, TemplateParams, NewVD, PrevVarTemplate); NewVD->setDescribedVarTemplate(NewTemplate); if (D.getDeclSpec().isModulePrivateSpecified()) NewTemplate->setModulePrivate(); // If we are providing an explicit specialization of a static variable // template, make a note of that. if (PrevVarTemplate && PrevVarTemplate->getInstantiatedFromMemberTemplate()) NewTemplate->setMemberSpecialization(); // Set the lexical context of this template NewTemplate->setLexicalDeclContext(CurContext); if (NewVD->isStaticDataMember() && NewVD->isOutOfLine()) NewTemplate->setAccess(NewVD->getAccess()); if (PrevVarTemplate) mergeDeclAttributes(NewVD, PrevVarTemplate->getTemplatedDecl()); AddPushedVisibilityAttribute(NewVD); PushOnScopeChains(NewTemplate, S); AddToScope = false; if (Invalid) { NewTemplate->setInvalidDecl(); NewVD->setInvalidDecl(); } ActOnDocumentableDecl(NewTemplate); return NewTemplate; } /// \brief Diagnose variable or built-in function shadowing. Implements /// -Wshadow. /// /// This method is called whenever a VarDecl is added to a "useful" /// scope. /// /// \param S the scope in which the shadowing name is being declared /// \param R the lookup of the name /// void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { // Return if warning is ignored. if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, R.getNameLoc()) == DiagnosticsEngine::Ignored) return; // Don't diagnose declarations at file scope. if (D->hasGlobalStorage()) return; DeclContext *NewDC = D->getDeclContext(); // Only diagnose if we're shadowing an unambiguous field or variable. if (R.getResultKind() != LookupResult::Found) return; NamedDecl* ShadowedDecl = R.getFoundDecl(); if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) return; // Fields are not shadowed by variables in C++ static methods. if (isa<FieldDecl>(ShadowedDecl)) if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) if (MD->isStatic()) return; if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl)) if (shadowedVar->isExternC()) { // For shadowing external vars, make sure that we point to the global // declaration, not a locally scoped extern declaration. for (VarDecl::redecl_iterator I = shadowedVar->redecls_begin(), E = shadowedVar->redecls_end(); I != E; ++I) if (I->isFileVarDecl()) { ShadowedDecl = *I; break; } } DeclContext *OldDC = ShadowedDecl->getDeclContext(); // Only warn about certain kinds of shadowing for class members. if (NewDC && NewDC->isRecord()) { // In particular, don't warn about shadowing non-class members. if (!OldDC->isRecord()) return; // TODO: should we warn about static data members shadowing // static data members from base classes? // TODO: don't diagnose for inaccessible shadowed members. // This is hard to do perfectly because we might friend the // shadowing context, but that's just a false negative. } // Determine what kind of declaration we're shadowing. unsigned Kind; if (isa<RecordDecl>(OldDC)) { if (isa<FieldDecl>(ShadowedDecl)) Kind = 3; // field else Kind = 2; // static data member } else if (OldDC->isFileContext()) Kind = 1; // global else Kind = 0; // local DeclarationName Name = R.getLookupName(); // Emit warning and note. Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); } /// \brief Check -Wshadow without the advantage of a previous lookup. void Sema::CheckShadow(Scope *S, VarDecl *D) { if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, D->getLocation()) == DiagnosticsEngine::Ignored) return; LookupResult R(*this, D->getDeclName(), D->getLocation(), Sema::LookupOrdinaryName, Sema::ForRedeclaration); LookupName(R, S); CheckShadow(S, D, R); } /// Check for conflict between this global or extern "C" declaration and /// previous global or extern "C" declarations. This is only used in C++. template<typename T> static bool checkGlobalOrExternCConflict( Sema &S, const T *ND, bool IsGlobal, LookupResult &Previous) { assert(S.getLangOpts().CPlusPlus && "only C++ has extern \"C\""); NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName()); if (!Prev && IsGlobal && !isIncompleteDeclExternC(S, ND)) { // The common case: this global doesn't conflict with any extern "C" // declaration. return false; } if (Prev) { if (!IsGlobal || isIncompleteDeclExternC(S, ND)) { // Both the old and new declarations have C language linkage. This is a // redeclaration. Previous.clear(); Previous.addDecl(Prev); return true; } // This is a global, non-extern "C" declaration, and there is a previous // non-global extern "C" declaration. Diagnose if this is a variable // declaration. if (!isa<VarDecl>(ND)) return false; } else { // The declaration is extern "C". Check for any declaration in the // translation unit which might conflict. if (IsGlobal) { // We have already performed the lookup into the translation unit. IsGlobal = false; for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); I != E; ++I) { if (isa<VarDecl>(*I)) { Prev = *I; break; } } } else { DeclContext::lookup_result R = S.Context.getTranslationUnitDecl()->lookup(ND->getDeclName()); for (DeclContext::lookup_result::iterator I = R.begin(), E = R.end(); I != E; ++I) { if (isa<VarDecl>(*I)) { Prev = *I; break; } // FIXME: If we have any other entity with this name in global scope, // the declaration is ill-formed, but that is a defect: it breaks the // 'stat' hack, for instance. Only variables can have mangled name // clashes with extern "C" declarations, so only they deserve a // diagnostic. } } if (!Prev) return false; } // Use the first declaration's location to ensure we point at something which // is lexically inside an extern "C" linkage-spec. assert(Prev && "should have found a previous declaration to diagnose"); if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Prev)) Prev = FD->getFirstDeclaration(); else Prev = cast<VarDecl>(Prev)->getFirstDeclaration(); S.Diag(ND->getLocation(), diag::err_extern_c_global_conflict) << IsGlobal << ND; S.Diag(Prev->getLocation(), diag::note_extern_c_global_conflict) << IsGlobal; return false; } /// Apply special rules for handling extern "C" declarations. Returns \c true /// if we have found that this is a redeclaration of some prior entity. /// /// Per C++ [dcl.link]p6: /// Two declarations [for a function or variable] with C language linkage /// with the same name that appear in different scopes refer to the same /// [entity]. An entity with C language linkage shall not be declared with /// the same name as an entity in global scope. template<typename T> static bool checkForConflictWithNonVisibleExternC(Sema &S, const T *ND, LookupResult &Previous) { if (!S.getLangOpts().CPlusPlus) { // In C, when declaring a global variable, look for a corresponding 'extern' // variable declared in function scope. // // FIXME: The corresponding case in C++ does not work. We should instead // set the semantic DC for an extern local variable to be the innermost // enclosing namespace, and ensure they are only found by redeclaration // lookup. if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) { if (NamedDecl *Prev = S.findLocallyScopedExternCDecl(ND->getDeclName())) { Previous.clear(); Previous.addDecl(Prev); return true; } } return false; } // A declaration in the translation unit can conflict with an extern "C" // declaration. if (ND->getDeclContext()->getRedeclContext()->isTranslationUnit()) return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/true, Previous); // An extern "C" declaration can conflict with a declaration in the // translation unit or can be a redeclaration of an extern "C" declaration // in another scope. if (isIncompleteDeclExternC(S,ND)) return checkGlobalOrExternCConflict(S, ND, /*IsGlobal*/false, Previous); // Neither global nor extern "C": nothing to do. return false; } void Sema::CheckVariableDeclarationType(VarDecl *NewVD) { // If the decl is already known invalid, don't check it. if (NewVD->isInvalidDecl()) return; TypeSourceInfo *TInfo = NewVD->getTypeSourceInfo(); QualType T = TInfo->getType(); // Defer checking an 'auto' type until its initializer is attached. if (T->isUndeducedType()) return; if (T->isObjCObjectType()) { Diag(NewVD->getLocation(), diag::err_statically_allocated_object) << FixItHint::CreateInsertion(NewVD->getLocation(), "*"); T = Context.getObjCObjectPointerType(T); NewVD->setType(T); } // Emit an error if an address space was applied to decl with local storage. // This includes arrays of objects with address space qualifiers, but not // automatic variables that point to other address spaces. // ISO/IEC TR 18037 S5.1.2 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); NewVD->setInvalidDecl(); return; } // OpenCL v1.2 s6.5 - All program scope variables must be declared in the // __constant address space. if (getLangOpts().OpenCL && NewVD->isFileVarDecl() && T.getAddressSpace() != LangAS::opencl_constant && !T->isSamplerT()){ Diag(NewVD->getLocation(), diag::err_opencl_global_invalid_addr_space); NewVD->setInvalidDecl(); return; } // OpenCL v1.2 s6.8 -- The static qualifier is valid only in program // scope. if ((getLangOpts().OpenCLVersion >= 120) && NewVD->isStaticLocal()) { Diag(NewVD->getLocation(), diag::err_static_function_scope); NewVD->setInvalidDecl(); return; } if (NewVD->hasLocalStorage() && T.isObjCGCWeak() && !NewVD->hasAttr<BlocksAttr>()) { if (getLangOpts().getGC() != LangOptions::NonGC) Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local); else { assert(!getLangOpts().ObjCAutoRefCount); Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); } } bool isVM = T->isVariablyModifiedType(); if (isVM || NewVD->hasAttr<CleanupAttr>() || NewVD->hasAttr<BlocksAttr>()) getCurFunction()->setHasBranchProtectedScope(); if ((isVM && NewVD->hasLinkage()) || (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { bool SizeIsNegative; llvm::APSInt Oversized; TypeSourceInfo *FixedTInfo = TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context, SizeIsNegative, Oversized); if (FixedTInfo == 0 && T->isVariableArrayType()) { const VariableArrayType *VAT = Context.getAsVariableArrayType(T); // FIXME: This won't give the correct result for // int a[10][n]; SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); if (NewVD->isFileVarDecl()) Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) << SizeRange; else if (NewVD->isStaticLocal()) Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) << SizeRange; else Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) << SizeRange; NewVD->setInvalidDecl(); return; } if (FixedTInfo == 0) { if (NewVD->isFileVarDecl()) Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); else Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); NewVD->setInvalidDecl(); return; } Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); NewVD->setType(FixedTInfo->getType()); NewVD->setTypeSourceInfo(FixedTInfo); } if (T->isVoidType()) { // C++98 [dcl.stc]p5: The extern specifier can be applied only to the names // of objects and functions. if (NewVD->isThisDeclarationADefinition() || getLangOpts().CPlusPlus) { Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) << T; NewVD->setInvalidDecl(); return; } } if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); NewVD->setInvalidDecl(); return; } if (isVM && NewVD->hasAttr<BlocksAttr>()) { Diag(NewVD->getLocation(), diag::err_block_on_vm); NewVD->setInvalidDecl(); return; } if (NewVD->isConstexpr() && !T->isDependentType() && RequireLiteralType(NewVD->getLocation(), T, diag::err_constexpr_var_non_literal)) { // Can't perform this check until the type is deduced. NewVD->setInvalidDecl(); return; } } /// \brief Perform semantic checking on a newly-created variable /// declaration. /// /// This routine performs all of the type-checking required for a /// variable declaration once it has been built. It is used both to /// check variables after they have been parsed and their declarators /// have been translated into a declaration, and to check variables /// that have been instantiated from a template. /// /// Sets NewVD->isInvalidDecl() if an error was encountered. /// /// Returns true if the variable declaration is a redeclaration. bool Sema::CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous) { CheckVariableDeclarationType(NewVD); // If the decl is already known invalid, don't check it. if (NewVD->isInvalidDecl()) return false; // If we did not find anything by this name, look for a non-visible // extern "C" declaration with the same name. // // Clang has a lot of problems with extern local declarations. // The actual standards text here is: // // C++11 [basic.link]p6: // The name of a function declared in block scope and the name // of a variable declared by a block scope extern declaration // have linkage. If there is a visible declaration of an entity // with linkage having the same name and type, ignoring entities // declared outside the innermost enclosing namespace scope, the // block scope declaration declares that same entity and // receives the linkage of the previous declaration. // // C11 6.2.7p4: // For an identifier with internal or external linkage declared // in a scope in which a prior declaration of that identifier is // visible, if the prior declaration specifies internal or // external linkage, the type of the identifier at the later // declaration becomes the composite type. // // The most important point here is that we're not allowed to // update our understanding of the type according to declarations // not in scope. bool PreviousWasHidden = Previous.empty() && checkForConflictWithNonVisibleExternC(*this, NewVD, Previous); // Filter out any non-conflicting previous declarations. filterNonConflictingPreviousDecls(Context, NewVD, Previous); if (!Previous.empty()) { MergeVarDecl(NewVD, Previous, PreviousWasHidden); return true; } return false; } /// \brief Data used with FindOverriddenMethod struct FindOverriddenMethodData { Sema *S; CXXMethodDecl *Method; }; /// \brief Member lookup function that determines whether a given C++ /// method overrides a method in a base class, to be used with /// CXXRecordDecl::lookupInBases(). static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, CXXBasePath &Path, void *UserData) { RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); FindOverriddenMethodData *Data = reinterpret_cast<FindOverriddenMethodData*>(UserData); DeclarationName Name = Data->Method->getDeclName(); // FIXME: Do we care about other names here too? if (Name.getNameKind() == DeclarationName::CXXDestructorName) { // We really want to find the base class destructor here. QualType T = Data->S->Context.getTypeDeclType(BaseRecord); CanQualType CT = Data->S->Context.getCanonicalType(T); Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); } for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty(); Path.Decls = Path.Decls.slice(1)) { NamedDecl *D = Path.Decls.front(); if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) return true; } } return false; } namespace { enum OverrideErrorKind { OEK_All, OEK_NonDeleted, OEK_Deleted }; } /// \brief Report an error regarding overriding, along with any relevant /// overriden methods. /// /// \param DiagID the primary error to report. /// \param MD the overriding method. /// \param OEK which overrides to include as notes. static void ReportOverrides(Sema& S, unsigned DiagID, const CXXMethodDecl *MD, OverrideErrorKind OEK = OEK_All) { S.Diag(MD->getLocation(), DiagID) << MD->getDeclName(); for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(), E = MD->end_overridden_methods(); I != E; ++I) { // This check (& the OEK parameter) could be replaced by a predicate, but // without lambdas that would be overkill. This is still nicer than writing // out the diag loop 3 times. if ((OEK == OEK_All) || (OEK == OEK_NonDeleted && !(*I)->isDeleted()) || (OEK == OEK_Deleted && (*I)->isDeleted())) S.Diag((*I)->getLocation(), diag::note_overridden_virtual_function); } } /// AddOverriddenMethods - See if a method overrides any in the base classes, /// and if so, check that it's a valid override and remember it. bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { // Look for virtual methods in base classes that this method might override. CXXBasePaths Paths; FindOverriddenMethodData Data; Data.Method = MD; Data.S = this; bool hasDeletedOverridenMethods = false; bool hasNonDeletedOverridenMethods = false; bool AddedAny = false; if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), E = Paths.found_decls_end(); I != E; ++I) { if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { MD->addOverriddenMethod(OldMD->getCanonicalDecl()); if (!CheckOverridingFunctionReturnType(MD, OldMD) && !CheckOverridingFunctionAttributes(MD, OldMD) && !CheckOverridingFunctionExceptionSpec(MD, OldMD) && !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) { hasDeletedOverridenMethods |= OldMD->isDeleted(); hasNonDeletedOverridenMethods |= !OldMD->isDeleted(); AddedAny = true; } } } } if (hasDeletedOverridenMethods && !MD->isDeleted()) { ReportOverrides(*this, diag::err_non_deleted_override, MD, OEK_Deleted); } if (hasNonDeletedOverridenMethods && MD->isDeleted()) { ReportOverrides(*this, diag::err_deleted_override, MD, OEK_NonDeleted); } return AddedAny; } namespace { // Struct for holding all of the extra arguments needed by // DiagnoseInvalidRedeclaration to call Sema::ActOnFunctionDeclarator. struct ActOnFDArgs { Scope *S; Declarator &D; MultiTemplateParamsArg TemplateParamLists; bool AddToScope; }; } namespace { // Callback to only accept typo corrections that have a non-zero edit distance. // Also only accept corrections that have the same parent decl. class DifferentNameValidatorCCC : public CorrectionCandidateCallback { public: DifferentNameValidatorCCC(ASTContext &Context, FunctionDecl *TypoFD, CXXRecordDecl *Parent) : Context(Context), OriginalFD(TypoFD), ExpectedParent(Parent ? Parent->getCanonicalDecl() : 0) {} virtual bool ValidateCandidate(const TypoCorrection &candidate) { if (candidate.getEditDistance() == 0) return false; SmallVector<unsigned, 1> MismatchedParams; for (TypoCorrection::const_decl_iterator CDecl = candidate.begin(), CDeclEnd = candidate.end(); CDecl != CDeclEnd; ++CDecl) { FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl); if (FD && !FD->hasBody() && hasSimilarParameters(Context, FD, OriginalFD, MismatchedParams)) { if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { CXXRecordDecl *Parent = MD->getParent(); if (Parent && Parent->getCanonicalDecl() == ExpectedParent) return true; } else if (!ExpectedParent) { return true; } } } return false; } private: ASTContext &Context; FunctionDecl *OriginalFD; CXXRecordDecl *ExpectedParent; }; } /// \brief Generate diagnostics for an invalid function redeclaration. /// /// This routine handles generating the diagnostic messages for an invalid /// function redeclaration, including finding possible similar declarations /// or performing typo correction if there are no previous declarations with /// the same name. /// /// Returns a NamedDecl iff typo correction was performed and substituting in /// the new declaration name does not cause new errors. static NamedDecl* DiagnoseInvalidRedeclaration( Sema &SemaRef, LookupResult &Previous, FunctionDecl *NewFD, ActOnFDArgs &ExtraArgs) { NamedDecl *Result = NULL; DeclarationName Name = NewFD->getDeclName(); DeclContext *NewDC = NewFD->getDeclContext(); LookupResult Prev(SemaRef, Name, NewFD->getLocation(), Sema::LookupOrdinaryName, Sema::ForRedeclaration); SmallVector<unsigned, 1> MismatchedParams; SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches; TypoCorrection Correction; bool isFriendDecl = (SemaRef.getLangOpts().CPlusPlus && ExtraArgs.D.getDeclSpec().isFriendSpecified()); unsigned DiagMsg = isFriendDecl ? diag::err_no_matching_local_friend : diag::err_member_def_does_not_match; NewFD->setInvalidDecl(); SemaRef.LookupQualifiedName(Prev, NewDC); assert(!Prev.isAmbiguous() && "Cannot have an ambiguity in previous-declaration lookup"); CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD); DifferentNameValidatorCCC Validator(SemaRef.Context, NewFD, MD ? MD->getParent() : 0); if (!Prev.empty()) { for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); Func != FuncEnd; ++Func) { FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func); if (FD && hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) { // Add 1 to the index so that 0 can mean the mismatch didn't // involve a parameter unsigned ParamNum = MismatchedParams.empty() ? 0 : MismatchedParams.front() + 1; NearMatches.push_back(std::make_pair(FD, ParamNum)); } } // If the qualified name lookup yielded nothing, try typo correction } else if ((Correction = SemaRef.CorrectTypo(Prev.getLookupNameInfo(), Prev.getLookupKind(), 0, 0, Validator, NewDC))) { // Trap errors. Sema::SFINAETrap Trap(SemaRef); // Set up everything for the call to ActOnFunctionDeclarator ExtraArgs.D.SetIdentifier(Correction.getCorrectionAsIdentifierInfo(), ExtraArgs.D.getIdentifierLoc()); Previous.clear(); Previous.setLookupName(Correction.getCorrection()); for (TypoCorrection::decl_iterator CDecl = Correction.begin(), CDeclEnd = Correction.end(); CDecl != CDeclEnd; ++CDecl) { FunctionDecl *FD = dyn_cast<FunctionDecl>(*CDecl); if (FD && !FD->hasBody() && hasSimilarParameters(SemaRef.Context, FD, NewFD, MismatchedParams)) { Previous.addDecl(FD); } } bool wasRedeclaration = ExtraArgs.D.isRedeclaration(); // TODO: Refactor ActOnFunctionDeclarator so that we can call only the // pieces need to verify the typo-corrected C++ declaraction and hopefully // eliminate the need for the parameter pack ExtraArgs. Result = SemaRef.ActOnFunctionDeclarator( ExtraArgs.S, ExtraArgs.D, Correction.getCorrectionDecl()->getDeclContext(), NewFD->getTypeSourceInfo(), Previous, ExtraArgs.TemplateParamLists, ExtraArgs.AddToScope); if (Trap.hasErrorOccurred()) { // Pretend the typo correction never occurred ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(), ExtraArgs.D.getIdentifierLoc()); ExtraArgs.D.setRedeclaration(wasRedeclaration); Previous.clear(); Previous.setLookupName(Name); Result = NULL; } else { for (LookupResult::iterator Func = Previous.begin(), FuncEnd = Previous.end(); Func != FuncEnd; ++Func) { if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func)) NearMatches.push_back(std::make_pair(FD, 0)); } } if (NearMatches.empty()) { // Ignore the correction if it didn't yield any close FunctionDecl matches Correction = TypoCorrection(); } else { DiagMsg = isFriendDecl ? diag::err_no_matching_local_friend_suggest : diag::err_member_def_does_not_match_suggest; } } if (Correction) { // FIXME: use Correction.getCorrectionRange() instead of computing the range // here. This requires passing in the CXXScopeSpec to CorrectTypo which in // turn causes the correction to fully qualify the name. If we fix // CorrectTypo to minimally qualify then this change should be good. SourceRange FixItLoc(NewFD->getLocation()); CXXScopeSpec &SS = ExtraArgs.D.getCXXScopeSpec(); if (Correction.getCorrectionSpecifier() && SS.isValid()) FixItLoc.setBegin(SS.getBeginLoc()); SemaRef.Diag(NewFD->getLocStart(), DiagMsg) << Name << NewDC << Correction.getQuoted(SemaRef.getLangOpts()) << FixItHint::CreateReplacement( FixItLoc, Correction.getAsString(SemaRef.getLangOpts())); } else { SemaRef.Diag(NewFD->getLocation(), DiagMsg) << Name << NewDC << NewFD->getLocation(); } bool NewFDisConst = false; if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) NewFDisConst = NewMD->isConst(); for (SmallVectorImpl<std::pair<FunctionDecl *, unsigned> >::iterator NearMatch = NearMatches.begin(), NearMatchEnd = NearMatches.end(); NearMatch != NearMatchEnd; ++NearMatch) { FunctionDecl *FD = NearMatch->first; bool FDisConst = false; if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) FDisConst = MD->isConst(); if (unsigned Idx = NearMatch->second) { ParmVarDecl *FDParam = FD->getParamDecl(Idx-1); SourceLocation Loc = FDParam->getTypeSpecStartLoc(); if (Loc.isInvalid()) Loc = FD->getLocation(); SemaRef.Diag(Loc, diag::note_member_def_close_param_match) << Idx << FDParam->getType() << NewFD->getParamDecl(Idx-1)->getType(); } else if (Correction) { SemaRef.Diag(FD->getLocation(), diag::note_previous_decl) << Correction.getQuoted(SemaRef.getLangOpts()); } else if (FDisConst != NewFDisConst) { SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match) << NewFDisConst << FD->getSourceRange().getEnd(); } else SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_match); } return Result; } static FunctionDecl::StorageClass getFunctionStorageClass(Sema &SemaRef, Declarator &D) { switch (D.getDeclSpec().getStorageClassSpec()) { default: llvm_unreachable("Unknown storage class!"); case DeclSpec::SCS_auto: case DeclSpec::SCS_register: case DeclSpec::SCS_mutable: SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(), diag::err_typecheck_sclass_func); D.setInvalidType(); break; case DeclSpec::SCS_unspecified: break; case DeclSpec::SCS_extern: if (D.getDeclSpec().isExternInLinkageSpec()) return SC_None; return SC_Extern; case DeclSpec::SCS_static: { if (SemaRef.CurContext->getRedeclContext()->isFunctionOrMethod()) { // C99 6.7.1p5: // The declaration of an identifier for a function that has // block scope shall have no explicit storage-class specifier // other than extern // See also (C++ [dcl.stc]p4). SemaRef.Diag(D.getDeclSpec().getStorageClassSpecLoc(), diag::err_static_block_func); break; } else return SC_Static; } case DeclSpec::SCS_private_extern: return SC_PrivateExtern; } // No explicit storage class has already been returned return SC_None; } static FunctionDecl* CreateNewFunctionDecl(Sema &SemaRef, Declarator &D, DeclContext *DC, QualType &R, TypeSourceInfo *TInfo, FunctionDecl::StorageClass SC, bool &IsVirtualOkay) { DeclarationNameInfo NameInfo = SemaRef.GetNameForDeclarator(D); DeclarationName Name = NameInfo.getName(); FunctionDecl *NewFD = 0; bool isInline = D.getDeclSpec().isInlineSpecified(); if (!SemaRef.getLangOpts().CPlusPlus) { // Determine whether the function was written with a // prototype. This true when: // - there is a prototype in the declarator, or // - the type R of the function is some kind of typedef or other reference // to a type name (which eventually refers to a function type). bool HasPrototype = (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) || (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); NewFD = FunctionDecl::Create(SemaRef.Context, DC, D.getLocStart(), NameInfo, R, TInfo, SC, isInline, HasPrototype, false); if (D.isInvalidType()) NewFD->setInvalidDecl(); // Set the lexical context. NewFD->setLexicalDeclContext(SemaRef.CurContext); return NewFD; } bool isExplicit = D.getDeclSpec().isExplicitSpecified(); bool isConstexpr = D.getDeclSpec().isConstexprSpecified(); // Check that the return type is not an abstract class type. // For record types, this is done by the AbstractClassUsageDiagnoser once // the class has been completely parsed. if (!DC->isRecord() && SemaRef.RequireNonAbstractType(D.getIdentifierLoc(), R->getAs<FunctionType>()->getResultType(), diag::err_abstract_type_in_decl, SemaRef.AbstractReturnType)) D.setInvalidType(); if (Name.getNameKind() == DeclarationName::CXXConstructorName) { // This is a C++ constructor declaration. assert(DC->isRecord() && "Constructors can only be declared in a member context"); R = SemaRef.CheckConstructorDeclarator(D, R, SC); return CXXConstructorDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC), D.getLocStart(), NameInfo, R, TInfo, isExplicit, isInline, /*isImplicitlyDeclared=*/false, isConstexpr); } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { // This is a C++ destructor declaration. if (DC->isRecord()) { R = SemaRef.CheckDestructorDeclarator(D, R, SC); CXXRecordDecl *Record = cast<CXXRecordDecl>(DC); CXXDestructorDecl *NewDD = CXXDestructorDecl::Create( SemaRef.Context, Record, D.getLocStart(), NameInfo, R, TInfo, isInline, /*isImplicitlyDeclared=*/false); // If the class is complete, then we now create the implicit exception // specification. If the class is incomplete or dependent, we can't do // it yet. if (SemaRef.getLangOpts().CPlusPlus11 && !Record->isDependentType() && Record->getDefinition() && !Record->isBeingDefined() && R->getAs<FunctionProtoType>()->getExceptionSpecType() == EST_None) { SemaRef.AdjustDestructorExceptionSpec(Record, NewDD); } // The Microsoft ABI requires that we perform the destructor body // checks (i.e. operator delete() lookup) at every declaration, as // any translation unit may need to emit a deleting destructor. if (SemaRef.Context.getTargetInfo().getCXXABI().isMicrosoft() && !Record->isDependentType() && Record->getDefinition() && !Record->isBeingDefined()) { SemaRef.CheckDestructor(NewDD); } IsVirtualOkay = true; return NewDD; } else { SemaRef.Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); D.setInvalidType(); // Create a FunctionDecl to satisfy the function definition parsing // code path. return FunctionDecl::Create(SemaRef.Context, DC, D.getLocStart(), D.getIdentifierLoc(), Name, R, TInfo, SC, isInline, /*hasPrototype=*/true, isConstexpr); } } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { if (!DC->isRecord()) { SemaRef.Diag(D.getIdentifierLoc(), diag::err_conv_function_not_member); return 0; } SemaRef.CheckConversionDeclarator(D, R, SC); IsVirtualOkay = true; return CXXConversionDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC), D.getLocStart(), NameInfo, R, TInfo, isInline, isExplicit, isConstexpr, SourceLocation()); } else if (DC->isRecord()) { // If the name of the function is the same as the name of the record, // then this must be an invalid constructor that has a return type. // (The parser checks for a return type and makes the declarator a // constructor if it has no return type). if (Name.getAsIdentifierInfo() && Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ SemaRef.Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) << SourceRange(D.getIdentifierLoc()); return 0; } // This is a C++ method declaration. CXXMethodDecl *Ret = CXXMethodDecl::Create(SemaRef.Context, cast<CXXRecordDecl>(DC), D.getLocStart(), NameInfo, R, TInfo, SC, isInline, isConstexpr, SourceLocation()); IsVirtualOkay = !Ret->isStatic(); return Ret; } else { // Determine whether the function was written with a // prototype. This true when: // - we're in C++ (where every function has a prototype), return FunctionDecl::Create(SemaRef.Context, DC, D.getLocStart(), NameInfo, R, TInfo, SC, isInline, true/*HasPrototype*/, isConstexpr); } } void Sema::checkVoidParamDecl(ParmVarDecl *Param) { // In C++, the empty parameter-type-list must be spelled "void"; a // typedef of void is not permitted. if (getLangOpts().CPlusPlus && Param->getType().getUnqualifiedType() != Context.VoidTy) { bool IsTypeAlias = false; if (const TypedefType *TT = Param->getType()->getAs<TypedefType>()) IsTypeAlias = isa<TypeAliasDecl>(TT->getDecl()); else if (const TemplateSpecializationType *TST = Param->getType()->getAs<TemplateSpecializationType>()) IsTypeAlias = TST->isTypeAlias(); Diag(Param->getLocation(), diag::err_param_typedef_of_void) << IsTypeAlias; } } enum OpenCLParamType { ValidKernelParam, PtrPtrKernelParam, PtrKernelParam, InvalidKernelParam, RecordKernelParam }; static OpenCLParamType getOpenCLKernelParameterType(QualType PT) { if (PT->isPointerType()) { QualType PointeeType = PT->getPointeeType(); return PointeeType->isPointerType() ? PtrPtrKernelParam : PtrKernelParam; } // TODO: Forbid the other integer types (size_t, ptrdiff_t...) when they can // be used as builtin types. if (PT->isImageType()) return PtrKernelParam; if (PT->isBooleanType()) return InvalidKernelParam; if (PT->isEventT()) return InvalidKernelParam; if (PT->isHalfType()) return InvalidKernelParam; if (PT->isRecordType()) return RecordKernelParam; return ValidKernelParam; } static void checkIsValidOpenCLKernelParameter( Sema &S, Declarator &D, ParmVarDecl *Param, llvm::SmallPtrSet<const Type *, 16> &ValidTypes) { QualType PT = Param->getType(); // Cache the valid types we encounter to avoid rechecking structs that are // used again if (ValidTypes.count(PT.getTypePtr())) return; switch (getOpenCLKernelParameterType(PT)) { case PtrPtrKernelParam: // OpenCL v1.2 s6.9.a: // A kernel function argument cannot be declared as a // pointer to a pointer type. S.Diag(Param->getLocation(), diag::err_opencl_ptrptr_kernel_param); D.setInvalidType(); return; // OpenCL v1.2 s6.9.k: // Arguments to kernel functions in a program cannot be declared with the // built-in scalar types bool, half, size_t, ptrdiff_t, intptr_t, and // uintptr_t or a struct and/or union that contain fields declared to be // one of these built-in scalar types. case InvalidKernelParam: // OpenCL v1.2 s6.8 n: // A kernel function argument cannot be declared // of event_t type. S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT; D.setInvalidType(); return; case PtrKernelParam: case ValidKernelParam: ValidTypes.insert(PT.getTypePtr()); return; case RecordKernelParam: break; } // Track nested structs we will inspect SmallVector<const Decl *, 4> VisitStack; // Track where we are in the nested structs. Items will migrate from // VisitStack to HistoryStack as we do the DFS for bad field. SmallVector<const FieldDecl *, 4> HistoryStack; HistoryStack.push_back((const FieldDecl *) 0); const RecordDecl *PD = PT->castAs<RecordType>()->getDecl(); VisitStack.push_back(PD); assert(VisitStack.back() && "First decl null?"); do { const Decl *Next = VisitStack.pop_back_val(); if (!Next) { assert(!HistoryStack.empty()); // Found a marker, we have gone up a level if (const FieldDecl *Hist = HistoryStack.pop_back_val()) ValidTypes.insert(Hist->getType().getTypePtr()); continue; } // Adds everything except the original parameter declaration (which is not a // field itself) to the history stack. const RecordDecl *RD; if (const FieldDecl *Field = dyn_cast<FieldDecl>(Next)) { HistoryStack.push_back(Field); RD = Field->getType()->castAs<RecordType>()->getDecl(); } else { RD = cast<RecordDecl>(Next); } // Add a null marker so we know when we've gone back up a level VisitStack.push_back((const Decl *) 0); for (RecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end(); I != E; ++I) { const FieldDecl *FD = *I; QualType QT = FD->getType(); if (ValidTypes.count(QT.getTypePtr())) continue; OpenCLParamType ParamType = getOpenCLKernelParameterType(QT); if (ParamType == ValidKernelParam) continue; if (ParamType == RecordKernelParam) { VisitStack.push_back(FD); continue; } // OpenCL v1.2 s6.9.p: // Arguments to kernel functions that are declared to be a struct or union // do not allow OpenCL objects to be passed as elements of the struct or // union. if (ParamType == PtrKernelParam || ParamType == PtrPtrKernelParam) { S.Diag(Param->getLocation(), diag::err_record_with_pointers_kernel_param) << PT->isUnionType() << PT; } else { S.Diag(Param->getLocation(), diag::err_bad_kernel_param_type) << PT; } S.Diag(PD->getLocation(), diag::note_within_field_of_type) << PD->getDeclName(); // We have an error, now let's go back up through history and show where // the offending field came from for (ArrayRef<const FieldDecl *>::const_iterator I = HistoryStack.begin() + 1, E = HistoryStack.end(); I != E; ++I) { const FieldDecl *OuterField = *I; S.Diag(OuterField->getLocation(), diag::note_within_field_of_type) << OuterField->getType(); } S.Diag(FD->getLocation(), diag::note_illegal_field_declared_here) << QT->isPointerType() << QT; D.setInvalidType(); return; } } while (!VisitStack.empty()); } NamedDecl* Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC, TypeSourceInfo *TInfo, LookupResult &Previous, MultiTemplateParamsArg TemplateParamLists, bool &AddToScope) { QualType R = TInfo->getType(); assert(R.getTypePtr()->isFunctionType()); // TODO: consider using NameInfo for diagnostic. DeclarationNameInfo NameInfo = GetNameForDeclarator(D); DeclarationName Name = NameInfo.getName(); FunctionDecl::StorageClass SC = getFunctionStorageClass(*this, D); if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(), diag::err_invalid_thread) << DeclSpec::getSpecifierName(TSCS); bool isFriend = false; FunctionTemplateDecl *FunctionTemplate = 0; bool isExplicitSpecialization = false; bool isFunctionTemplateSpecialization = false; bool isDependentClassScopeExplicitSpecialization = false; bool HasExplicitTemplateArgs = false; TemplateArgumentListInfo TemplateArgs; bool isVirtualOkay = false; FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC, isVirtualOkay); if (!NewFD) return 0; if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer()) NewFD->setTopLevelDeclInObjCContainer(); if (getLangOpts().CPlusPlus) { bool isInline = D.getDeclSpec().isInlineSpecified(); bool isVirtual = D.getDeclSpec().isVirtualSpecified(); bool isExplicit = D.getDeclSpec().isExplicitSpecified(); bool isConstexpr = D.getDeclSpec().isConstexprSpecified(); isFriend = D.getDeclSpec().isFriendSpecified(); if (isFriend && !isInline && D.isFunctionDefinition()) { // C++ [class.friend]p5 // A function can be defined in a friend declaration of a // class . . . . Such a function is implicitly inline. NewFD->setImplicitlyInline(); } // If this is a method defined in an __interface, and is not a constructor // or an overloaded operator, then set the pure flag (isVirtual will already // return true). if (const CXXRecordDecl *Parent = dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) { if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided()) NewFD->setPure(true); } SetNestedNameSpecifier(NewFD, D); isExplicitSpecialization = false; isFunctionTemplateSpecialization = false; if (D.isInvalidType()) NewFD->setInvalidDecl(); // Set the lexical context. If the declarator has a C++ // scope specifier, or is the object of a friend declaration, the // lexical context will be different from the semantic context. NewFD->setLexicalDeclContext(CurContext); // Match up the template parameter lists with the scope specifier, then // determine whether we have a template or a template specialization. bool Invalid = false; if (TemplateParameterList *TemplateParams = MatchTemplateParametersToScopeSpecifier( D.getDeclSpec().getLocStart(), D.getIdentifierLoc(), D.getCXXScopeSpec(), TemplateParamLists, isFriend, isExplicitSpecialization, Invalid)) { if (TemplateParams->size() > 0) { // This is a function template // Check that we can declare a template here. if (CheckTemplateDeclScope(S, TemplateParams)) return 0; // A destructor cannot be a template. if (Name.getNameKind() == DeclarationName::CXXDestructorName) { Diag(NewFD->getLocation(), diag::err_destructor_template); return 0; } // If we're adding a template to a dependent context, we may need to // rebuilding some of the types used within the template parameter list, // now that we know what the current instantiation is. if (DC->isDependentContext()) { ContextRAII SavedContext(*this, DC); if (RebuildTemplateParamsInCurrentInstantiation(TemplateParams)) Invalid = true; } FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, NewFD->getLocation(), Name, TemplateParams, NewFD); FunctionTemplate->setLexicalDeclContext(CurContext); NewFD->setDescribedFunctionTemplate(FunctionTemplate); // For source fidelity, store the other template param lists. if (TemplateParamLists.size() > 1) { NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists.size() - 1, TemplateParamLists.data()); } } else { // This is a function template specialization. isFunctionTemplateSpecialization = true; // For source fidelity, store all the template param lists. NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists.size(), TemplateParamLists.data()); // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". if (isFriend) { // We want to remove the "template<>", found here. SourceRange RemoveRange = TemplateParams->getSourceRange(); // If we remove the template<> and the name is not a // template-id, we're actually silently creating a problem: // the friend declaration will refer to an untemplated decl, // and clearly the user wants a template specialization. So // we need to insert '<>' after the name. SourceLocation InsertLoc; if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { InsertLoc = D.getName().getSourceRange().getEnd(); InsertLoc = PP.getLocForEndOfToken(InsertLoc); } Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) << Name << RemoveRange << FixItHint::CreateRemoval(RemoveRange) << FixItHint::CreateInsertion(InsertLoc, "<>"); } } } else { // All template param lists were matched against the scope specifier: // this is NOT (an explicit specialization of) a template. if (TemplateParamLists.size() > 0) // For source fidelity, store all the template param lists. NewFD->setTemplateParameterListsInfo(Context, TemplateParamLists.size(), TemplateParamLists.data()); } if (Invalid) { NewFD->setInvalidDecl(); if (FunctionTemplate) FunctionTemplate->setInvalidDecl(); } // C++ [dcl.fct.spec]p5: // The virtual specifier shall only be used in declarations of // nonstatic class member functions that appear within a // member-specification of a class declaration; see 10.3. // if (isVirtual && !NewFD->isInvalidDecl()) { if (!isVirtualOkay) { Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_non_function); } else if (!CurContext->isRecord()) { // 'virtual' was specified outside of the class. Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); } else if (NewFD->getDescribedFunctionTemplate()) { // C++ [temp.mem]p3: // A member function template shall not be virtual. Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_member_function_template) << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); } else { // Okay: Add virtual to the method. NewFD->setVirtualAsWritten(true); } if (getLangOpts().CPlusPlus1y && NewFD->getResultType()->isUndeducedType()) Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_auto_fn_virtual); } // C++ [dcl.fct.spec]p3: // The inline specifier shall not appear on a block scope function // declaration. if (isInline && !NewFD->isInvalidDecl()) { if (CurContext->isFunctionOrMethod()) { // 'inline' is not allowed on block scope function declaration. Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_declaration_block_scope) << Name << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); } } // C++ [dcl.fct.spec]p6: // The explicit specifier shall be used only in the declaration of a // constructor or conversion function within its class definition; // see 12.3.1 and 12.3.2. if (isExplicit && !NewFD->isInvalidDecl()) { if (!CurContext->isRecord()) { // 'explicit' was specified outside of the class. Diag(D.getDeclSpec().getExplicitSpecLoc(), diag::err_explicit_out_of_class) << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); } else if (!isa<CXXConstructorDecl>(NewFD) && !isa<CXXConversionDecl>(NewFD)) { // 'explicit' was specified on a function that wasn't a constructor // or conversion function. Diag(D.getDeclSpec().getExplicitSpecLoc(), diag::err_explicit_non_ctor_or_conv_function) << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); } } if (isConstexpr) { // C++11 [dcl.constexpr]p2: constexpr functions and constexpr constructors // are implicitly inline. NewFD->setImplicitlyInline(); // C++11 [dcl.constexpr]p3: functions declared constexpr are required to // be either constructors or to return a literal type. Therefore, // destructors cannot be declared constexpr. if (isa<CXXDestructorDecl>(NewFD)) Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_constexpr_dtor); } // If __module_private__ was specified, mark the function accordingly. if (D.getDeclSpec().isModulePrivateSpecified()) { if (isFunctionTemplateSpecialization) { SourceLocation ModulePrivateLoc = D.getDeclSpec().getModulePrivateSpecLoc(); Diag(ModulePrivateLoc, diag::err_module_private_specialization) << 0 << FixItHint::CreateRemoval(ModulePrivateLoc); } else { NewFD->setModulePrivate(); if (FunctionTemplate) FunctionTemplate->setModulePrivate(); } } if (isFriend) { if (FunctionTemplate) { FunctionTemplate->setObjectOfFriendDecl(); FunctionTemplate->setAccess(AS_public); } NewFD->setObjectOfFriendDecl(); NewFD->setAccess(AS_public); } // If a function is defined as defaulted or deleted, mark it as such now. switch (D.getFunctionDefinitionKind()) { case FDK_Declaration: case FDK_Definition: break; case FDK_Defaulted: NewFD->setDefaulted(); break; case FDK_Deleted: NewFD->setDeletedAsWritten(); break; } if (isa<CXXMethodDecl>(NewFD) && DC == CurContext && D.isFunctionDefinition()) { // C++ [class.mfct]p2: // A member function may be defined (8.4) in its class definition, in // which case it is an inline member function (7.1.2) NewFD->setImplicitlyInline(); } if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && !CurContext->isRecord()) { // C++ [class.static]p1: // A data or function member of a class may be declared static // in a class definition, in which case it is a static member of // the class. // Complain about the 'static' specifier if it's on an out-of-line // member function definition. Diag(D.getDeclSpec().getStorageClassSpecLoc(), diag::err_static_out_of_line) << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); } // C++11 [except.spec]p15: // A deallocation function with no exception-specification is treated // as if it were specified with noexcept(true). const FunctionProtoType *FPT = R->getAs<FunctionProtoType>(); if ((Name.getCXXOverloadedOperator() == OO_Delete || Name.getCXXOverloadedOperator() == OO_Array_Delete) && getLangOpts().CPlusPlus11 && FPT && !FPT->hasExceptionSpec()) { FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo(); EPI.ExceptionSpecType = EST_BasicNoexcept; NewFD->setType(Context.getFunctionType(FPT->getResultType(), FPT->getArgTypes(), EPI)); } } // Filter out previous declarations that don't match the scope. FilterLookupForScope(Previous, DC, S, shouldConsiderLinkage(NewFD), isExplicitSpecialization || isFunctionTemplateSpecialization); // Handle GNU asm-label extension (encoded as an attribute). if (Expr *E = (Expr*) D.getAsmLabel()) { // The parser guarantees this is a string. StringLiteral *SE = cast<StringLiteral>(E); NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, SE->getString())); } else if (!ExtnameUndeclaredIdentifiers.empty()) { llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*>::iterator I = ExtnameUndeclaredIdentifiers.find(NewFD->getIdentifier()); if (I != ExtnameUndeclaredIdentifiers.end()) { NewFD->addAttr(I->second); ExtnameUndeclaredIdentifiers.erase(I); } } // Copy the parameter declarations from the declarator D to the function // declaration NewFD, if they are available. First scavenge them into Params. SmallVector<ParmVarDecl*, 16> Params; if (D.isFunctionDeclarator()) { DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs // function that takes no arguments, not a function that takes a // single void argument. // We let through "const void" here because Sema::GetTypeForDeclarator // already checks for that case. if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && FTI.ArgInfo[0].Param && cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { // Empty arg list, don't push any params. checkVoidParamDecl(cast<ParmVarDecl>(FTI.ArgInfo[0].Param)); } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); assert(Param->getDeclContext() != NewFD && "Was set before ?"); Param->setDeclContext(NewFD); Params.push_back(Param); if (Param->isInvalidDecl()) NewFD->setInvalidDecl(); } } } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { // When we're declaring a function with a typedef, typeof, etc as in the // following example, we'll need to synthesize (unnamed) // parameters for use in the declaration. // // @code // typedef void fn(int); // fn f; // @endcode // Synthesize a parameter for each argument type. for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), AE = FT->arg_type_end(); AI != AE; ++AI) { ParmVarDecl *Param = BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); Param->setScopeInfo(0, Params.size()); Params.push_back(Param); } } else { assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && "Should not need args for typedef of non-prototype fn"); } // Finally, we know we have the right number of parameters, install them. NewFD->setParams(Params); // Find all anonymous symbols defined during the declaration of this function // and add to NewFD. This lets us track decls such 'enum Y' in: // // void f(enum Y {AA} x) {} // // which would otherwise incorrectly end up in the translation unit scope. NewFD->setDeclsInPrototypeScope(DeclsInPrototypeScope); DeclsInPrototypeScope.clear(); if (D.getDeclSpec().isNoreturnSpecified()) NewFD->addAttr( ::new(Context) C11NoReturnAttr(D.getDeclSpec().getNoreturnSpecLoc(), Context)); // Process the non-inheritable attributes on this declaration. ProcessDeclAttributes(S, NewFD, D, /*NonInheritable=*/true, /*Inheritable=*/false); // Functions returning a variably modified type violate C99 6.7.5.2p2 // because all functions have linkage. if (!NewFD->isInvalidDecl() && NewFD->getResultType()->isVariablyModifiedType()) { Diag(NewFD->getLocation(), diag::err_vm_func_decl); NewFD->setInvalidDecl(); } // Handle attributes. ProcessDeclAttributes(S, NewFD, D, /*NonInheritable=*/false, /*Inheritable=*/true); QualType RetType = NewFD->getResultType(); const CXXRecordDecl *Ret = RetType->isRecordType() ? RetType->getAsCXXRecordDecl() : RetType->getPointeeCXXRecordDecl(); if (!NewFD->isInvalidDecl() && !NewFD->hasAttr<WarnUnusedResultAttr>() && Ret && Ret->hasAttr<WarnUnusedResultAttr>()) { const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD); if (!(MD && MD->getCorrespondingMethodInClass(Ret, true))) { NewFD->addAttr(new (Context) WarnUnusedResultAttr(SourceRange(), Context)); } } if (!getLangOpts().CPlusPlus) { // Perform semantic checking on the function declaration. bool isExplicitSpecialization=false; if (!NewFD->isInvalidDecl() && NewFD->isMain()) CheckMain(NewFD, D.getDeclSpec()); if (!NewFD->isInvalidDecl()) D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization)); // Make graceful recovery from an invalid redeclaration. else if (!Previous.empty()) D.setRedeclaration(true); assert((NewFD->isInvalidDecl() || !D.isRedeclaration() || Previous.getResultKind() != LookupResult::FoundOverloaded) && "previous declaration set still overloaded"); } else { // If the declarator is a template-id, translate the parser's template // argument list into our AST format. if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { TemplateIdAnnotation *TemplateId = D.getName().TemplateId; TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), TemplateId->NumArgs); translateTemplateArguments(TemplateArgsPtr, TemplateArgs); HasExplicitTemplateArgs = true; if (NewFD->isInvalidDecl()) { HasExplicitTemplateArgs = false; } else if (FunctionTemplate) { // Function template with explicit template arguments. Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec) << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc); HasExplicitTemplateArgs = false; } else if (!isFunctionTemplateSpecialization && !D.getDeclSpec().isFriendSpecified()) { // We have encountered something that the user meant to be a // specialization (because it has explicitly-specified template // arguments) but that was not introduced with a "template<>" (or had // too few of them). // FIXME: Differentiate between attempts for explicit instantiations // (starting with "template") and the rest. Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) << FixItHint::CreateInsertion( D.getDeclSpec().getLocStart(), "template<> "); isFunctionTemplateSpecialization = true; } else { // "friend void foo<>(int);" is an implicit specialization decl. isFunctionTemplateSpecialization = true; } } else if (isFriend && isFunctionTemplateSpecialization) { // This combination is only possible in a recovery case; the user // wrote something like: // template <> friend void foo(int); // which we're recovering from as if the user had written: // friend void foo<>(int); // Go ahead and fake up a template id. HasExplicitTemplateArgs = true; TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); } // If it's a friend (and only if it's a friend), it's possible // that either the specialized function type or the specialized // template is dependent, and therefore matching will fail. In // this case, don't check the specialization yet. bool InstantiationDependent = false; if (isFunctionTemplateSpecialization && isFriend && (NewFD->getType()->isDependentType() || DC->isDependentContext() || TemplateSpecializationType::anyDependentTemplateArguments( TemplateArgs.getArgumentArray(), TemplateArgs.size(), InstantiationDependent))) { assert(HasExplicitTemplateArgs && "friend function specialization without template args"); if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, Previous)) NewFD->setInvalidDecl(); } else if (isFunctionTemplateSpecialization) { if (CurContext->isDependentContext() && CurContext->isRecord() && !isFriend) { isDependentClassScopeExplicitSpecialization = true; Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ? diag::ext_function_specialization_in_class : diag::err_function_specialization_in_class) << NewFD->getDeclName(); } else if (CheckFunctionTemplateSpecialization(NewFD, (HasExplicitTemplateArgs ? &TemplateArgs : 0), Previous)) NewFD->setInvalidDecl(); // C++ [dcl.stc]p1: // A storage-class-specifier shall not be specified in an explicit // specialization (14.7.3) FunctionTemplateSpecializationInfo *Info = NewFD->getTemplateSpecializationInfo(); if (Info && SC != SC_None) { if (SC != Info->getTemplate()->getTemplatedDecl()->getStorageClass()) Diag(NewFD->getLocation(), diag::err_explicit_specialization_inconsistent_storage_class) << SC << FixItHint::CreateRemoval( D.getDeclSpec().getStorageClassSpecLoc()); else Diag(NewFD->getLocation(), diag::ext_explicit_specialization_storage_class) << FixItHint::CreateRemoval( D.getDeclSpec().getStorageClassSpecLoc()); } } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { if (CheckMemberSpecialization(NewFD, Previous)) NewFD->setInvalidDecl(); } // Perform semantic checking on the function declaration. if (!isDependentClassScopeExplicitSpecialization) { if (!NewFD->isInvalidDecl() && NewFD->isMain()) CheckMain(NewFD, D.getDeclSpec()); if (NewFD->isInvalidDecl()) { // If this is a class member, mark the class invalid immediately. // This avoids some consistency errors later. if (CXXMethodDecl* methodDecl = dyn_cast<CXXMethodDecl>(NewFD)) methodDecl->getParent()->setInvalidDecl(); } else D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization)); } assert((NewFD->isInvalidDecl() || !D.isRedeclaration() || Previous.getResultKind() != LookupResult::FoundOverloaded) && "previous declaration set still overloaded"); NamedDecl *PrincipalDecl = (FunctionTemplate ? cast<NamedDecl>(FunctionTemplate) : NewFD); if (isFriend && D.isRedeclaration()) { AccessSpecifier Access = AS_public; if (!NewFD->isInvalidDecl()) Access = NewFD->getPreviousDecl()->getAccess(); NewFD->setAccess(Access); if (FunctionTemplate) FunctionTemplate->setAccess(Access); } if (NewFD->isOverloadedOperator() && !DC->isRecord() && PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) PrincipalDecl->setNonMemberOperator(); // If we have a function template, check the template parameter // list. This will check and merge default template arguments. if (FunctionTemplate) { FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDecl(); CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), PrevTemplate ? PrevTemplate->getTemplateParameters() : 0, D.getDeclSpec().isFriendSpecified() ? (D.isFunctionDefinition() ? TPC_FriendFunctionTemplateDefinition : TPC_FriendFunctionTemplate) : (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() && DC->isDependentContext()) ? TPC_ClassTemplateMember : TPC_FunctionTemplate); } if (NewFD->isInvalidDecl()) { // Ignore all the rest of this. } else if (!D.isRedeclaration()) { struct ActOnFDArgs ExtraArgs = { S, D, TemplateParamLists, AddToScope }; // Fake up an access specifier if it's supposed to be a class member. if (isa<CXXRecordDecl>(NewFD->getDeclContext())) NewFD->setAccess(AS_public); // Qualified decls generally require a previous declaration. if (D.getCXXScopeSpec().isSet()) { // ...with the major exception of templated-scope or // dependent-scope friend declarations. // TODO: we currently also suppress this check in dependent // contexts because (1) the parameter depth will be off when // matching friend templates and (2) we might actually be // selecting a friend based on a dependent factor. But there // are situations where these conditions don't apply and we // can actually do this check immediately. if (isFriend && (TemplateParamLists.size() || D.getCXXScopeSpec().getScopeRep()->isDependent() || CurContext->isDependentContext())) { // ignore these } else { // The user tried to provide an out-of-line definition for a // function that is a member of a class or namespace, but there // was no such member function declared (C++ [class.mfct]p2, // C++ [namespace.memdef]p2). For example: // // class X { // void f() const; // }; // // void X::f() { } // ill-formed // // Complain about this problem, and attempt to suggest close // matches (e.g., those that differ only in cv-qualifiers and // whether the parameter types are references). if (NamedDecl *Result = DiagnoseInvalidRedeclaration(*this, Previous, NewFD, ExtraArgs)) { AddToScope = ExtraArgs.AddToScope; return Result; } } // Unqualified local friend declarations are required to resolve // to something. } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { if (NamedDecl *Result = DiagnoseInvalidRedeclaration(*this, Previous, NewFD, ExtraArgs)) { AddToScope = ExtraArgs.AddToScope; return Result; } } } else if (!D.isFunctionDefinition() && D.getCXXScopeSpec().isSet() && !isFriend && !isFunctionTemplateSpecialization && !isExplicitSpecialization) { // An out-of-line member function declaration must also be a // definition (C++ [dcl.meaning]p1). // Note that this is not the case for explicit specializations of // function templates or member functions of class templates, per // C++ [temp.expl.spec]p2. We also allow these declarations as an // extension for compatibility with old SWIG code which likes to // generate them. Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) << D.getCXXScopeSpec().getRange(); } } ProcessPragmaWeak(S, NewFD); checkAttributesAfterMerging(*this, *NewFD); AddKnownFunctionAttributes(NewFD); if (NewFD->hasAttr<OverloadableAttr>() && !NewFD->getType()->getAs<FunctionProtoType>()) { Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) << NewFD; // Turn this into a variadic function with no parameters. const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); FunctionProtoType::ExtProtoInfo EPI; EPI.Variadic = true; EPI.ExtInfo = FT->getExtInfo(); QualType R = Context.getFunctionType(FT->getResultType(), None, EPI); NewFD->setType(R); } // If there's a #pragma GCC visibility in scope, and this isn't a class // member, set the visibility of this function. if (!DC->isRecord() && NewFD->isExternallyVisible()) AddPushedVisibilityAttribute(NewFD); // If there's a #pragma clang arc_cf_code_audited in scope, consider // marking the function. AddCFAuditedAttribute(NewFD); // If this is the first declaration of an extern C variable, update // the map of such variables. if (!NewFD->getPreviousDecl() && !NewFD->isInvalidDecl() && isIncompleteDeclExternC(*this, NewFD)) RegisterLocallyScopedExternCDecl(NewFD, S); // Set this FunctionDecl's range up to the right paren. NewFD->setRangeEnd(D.getSourceRange().getEnd()); if (getLangOpts().CPlusPlus) { if (FunctionTemplate) { if (NewFD->isInvalidDecl()) FunctionTemplate->setInvalidDecl(); return FunctionTemplate; } } if (NewFD->hasAttr<OpenCLKernelAttr>()) { // OpenCL v1.2 s6.8 static is invalid for kernel functions. if ((getLangOpts().OpenCLVersion >= 120) && (SC == SC_Static)) { Diag(D.getIdentifierLoc(), diag::err_static_kernel); D.setInvalidType(); } // OpenCL v1.2, s6.9 -- Kernels can only have return type void. if (!NewFD->getResultType()->isVoidType()) { Diag(D.getIdentifierLoc(), diag::err_expected_kernel_void_return_type); D.setInvalidType(); } llvm::SmallPtrSet<const Type *, 16> ValidTypes; for (FunctionDecl::param_iterator PI = NewFD->param_begin(), PE = NewFD->param_end(); PI != PE; ++PI) { ParmVarDecl *Param = *PI; checkIsValidOpenCLKernelParameter(*this, D, Param, ValidTypes); } } MarkUnusedFileScopedDecl(NewFD); if (getLangOpts().CUDA) if (IdentifierInfo *II = NewFD->getIdentifier()) if (!NewFD->isInvalidDecl() && NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { if (II->isStr("cudaConfigureCall")) { if (!R->getAs<FunctionType>()->getResultType()->isScalarType()) Diag(NewFD->getLocation(), diag::err_config_scalar_return); Context.setcudaConfigureCallDecl(NewFD); } } // Here we have an function template explicit specialization at class scope. // The actually specialization will be postponed to template instatiation // time via the ClassScopeFunctionSpecializationDecl node. if (isDependentClassScopeExplicitSpecialization) { ClassScopeFunctionSpecializationDecl *NewSpec = ClassScopeFunctionSpecializationDecl::Create( Context, CurContext, SourceLocation(), cast<CXXMethodDecl>(NewFD), HasExplicitTemplateArgs, TemplateArgs); CurContext->addDecl(NewSpec); AddToScope = false; } return NewFD; } /// \brief Perform semantic checking of a new function declaration. /// /// Performs semantic analysis of the new function declaration /// NewFD. This routine performs all semantic checking that does not /// require the actual declarator involved in the declaration, and is /// used both for the declaration of functions as they are parsed /// (called via ActOnDeclarator) and for the declaration of functions /// that have been instantiated via C++ template instantiation (called /// via InstantiateDecl). /// /// \param IsExplicitSpecialization whether this new function declaration is /// an explicit specialization of the previous declaration. /// /// This sets NewFD->isInvalidDecl() to true if there was an error. /// /// \returns true if the function declaration is a redeclaration. bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, LookupResult &Previous, bool IsExplicitSpecialization) { assert(!NewFD->getResultType()->isVariablyModifiedType() && "Variably modified return types are not handled here"); // Filter out any non-conflicting previous declarations. filterNonConflictingPreviousDecls(Context, NewFD, Previous); bool Redeclaration = false; NamedDecl *OldDecl = 0; // Merge or overload the declaration with an existing declaration of // the same name, if appropriate. if (!Previous.empty()) { // Determine whether NewFD is an overload of PrevDecl or // a declaration that requires merging. If it's an overload, // there's no more work to do here; we'll just add the new // function to the scope. if (!AllowOverloadingOfFunction(Previous, Context)) { NamedDecl *Candidate = Previous.getFoundDecl(); if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) { Redeclaration = true; OldDecl = Candidate; } } else { switch (CheckOverload(S, NewFD, Previous, OldDecl, /*NewIsUsingDecl*/ false)) { case Ovl_Match: Redeclaration = true; break; case Ovl_NonFunction: Redeclaration = true; break; case Ovl_Overload: Redeclaration = false; break; } if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) { // If a function name is overloadable in C, then every function // with that name must be marked "overloadable". Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) << Redeclaration << NewFD; NamedDecl *OverloadedDecl = 0; if (Redeclaration) OverloadedDecl = OldDecl; else if (!Previous.empty()) OverloadedDecl = Previous.getRepresentativeDecl(); if (OverloadedDecl) Diag(OverloadedDecl->getLocation(), diag::note_attribute_overloadable_prev_overload); NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); } } } // Check for a previous extern "C" declaration with this name. if (!Redeclaration && checkForConflictWithNonVisibleExternC(*this, NewFD, Previous)) { filterNonConflictingPreviousDecls(Context, NewFD, Previous); if (!Previous.empty()) { // This is an extern "C" declaration with the same name as a previous // declaration, and thus redeclares that entity... Redeclaration = true; OldDecl = Previous.getFoundDecl(); // ... except in the presence of __attribute__((overloadable)). if (OldDecl->hasAttr<OverloadableAttr>()) { if (!getLangOpts().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) { Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) << Redeclaration << NewFD; Diag(Previous.getFoundDecl()->getLocation(), diag::note_attribute_overloadable_prev_overload); NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), Context)); } if (IsOverload(NewFD, cast<FunctionDecl>(OldDecl), false)) { Redeclaration = false; OldDecl = 0; } } } } // C++11 [dcl.constexpr]p8: // A constexpr specifier for a non-static member function that is not // a constructor declares that member function to be const. // // This needs to be delayed until we know whether this is an out-of-line // definition of a static member function. // // This rule is not present in C++1y, so we produce a backwards // compatibility warning whenever it happens in C++11. CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD); if (!getLangOpts().CPlusPlus1y && MD && MD->isConstexpr() && !MD->isStatic() && !isa<CXXConstructorDecl>(MD) && (MD->getTypeQualifiers() & Qualifiers::Const) == 0) { CXXMethodDecl *OldMD = dyn_cast_or_null<CXXMethodDecl>(OldDecl); if (FunctionTemplateDecl *OldTD = dyn_cast_or_null<FunctionTemplateDecl>(OldDecl)) OldMD = dyn_cast<CXXMethodDecl>(OldTD->getTemplatedDecl()); if (!OldMD || !OldMD->isStatic()) { const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>(); FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo(); EPI.TypeQuals |= Qualifiers::Const; MD->setType(Context.getFunctionType(FPT->getResultType(), FPT->getArgTypes(), EPI)); // Warn that we did this, if we're not performing template instantiation. // In that case, we'll have warned already when the template was defined. if (ActiveTemplateInstantiations.empty()) { SourceLocation AddConstLoc; if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc() .IgnoreParens().getAs<FunctionTypeLoc>()) AddConstLoc = PP.getLocForEndOfToken(FTL.getRParenLoc()); Diag(MD->getLocation(), diag::warn_cxx1y_compat_constexpr_not_const) << FixItHint::CreateInsertion(AddConstLoc, " const"); } } } if (Redeclaration) { // NewFD and OldDecl represent declarations that need to be // merged. if (MergeFunctionDecl(NewFD, OldDecl, S)) { NewFD->setInvalidDecl(); return Redeclaration; } Previous.clear(); Previous.addDecl(OldDecl); if (FunctionTemplateDecl *OldTemplateDecl = dyn_cast<FunctionTemplateDecl>(OldDecl)) { NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); FunctionTemplateDecl *NewTemplateDecl = NewFD->getDescribedFunctionTemplate(); assert(NewTemplateDecl && "Template/non-template mismatch"); if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { Method->setAccess(OldTemplateDecl->getAccess()); NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); } // If this is an explicit specialization of a member that is a function // template, mark it as a member specialization. if (IsExplicitSpecialization && NewTemplateDecl->getInstantiatedFromMemberTemplate()) { NewTemplateDecl->setMemberSpecialization(); assert(OldTemplateDecl->isMemberSpecialization()); } } else { // This needs to happen first so that 'inline' propagates. NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); if (isa<CXXMethodDecl>(NewFD)) { // A valid redeclaration of a C++ method must be out-of-line, // but (unfortunately) it's not necessarily a definition // because of templates, which means that the previous // declaration is not necessarily from the class definition. // For just setting the access, that doesn't matter. CXXMethodDecl *oldMethod = cast<CXXMethodDecl>(OldDecl); NewFD->setAccess(oldMethod->getAccess()); // Update the key-function state if necessary for this ABI. if (NewFD->isInlined() && !Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline()) { // setNonKeyFunction needs to work with the original // declaration from the class definition, and isVirtual() is // just faster in that case, so map back to that now. oldMethod = cast<CXXMethodDecl>(oldMethod->getFirstDeclaration()); if (oldMethod->isVirtual()) { Context.setNonKeyFunction(oldMethod); } } } } } // Semantic checking for this function declaration (in isolation). if (getLangOpts().CPlusPlus) { // C++-specific checks. if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { CheckConstructor(Constructor); } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) { CXXRecordDecl *Record = Destructor->getParent(); QualType ClassType = Context.getTypeDeclType(Record); // FIXME: Shouldn't we be able to perform this check even when the class // type is dependent? Both gcc and edg can handle that. if (!ClassType->isDependentType()) { DeclarationName Name = Context.DeclarationNames.getCXXDestructorName( Context.getCanonicalType(ClassType)); if (NewFD->getDeclName() != Name) { Diag(NewFD->getLocation(), diag::err_destructor_name); NewFD->setInvalidDecl(); return Redeclaration; } } } else if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(NewFD)) { ActOnConversionDeclarator(Conversion); } // Find any virtual functions that this function overrides. if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { if (!Method->isFunctionTemplateSpecialization() && !Method->getDescribedFunctionTemplate() && Method->isCanonicalDecl()) { if (AddOverriddenMethods(Method->getParent(), Method)) { // If the function was marked as "static", we have a problem. if (NewFD->getStorageClass() == SC_Static) { ReportOverrides(*this, diag::err_static_overrides_virtual, Method); } } } if (Method->isStatic()) checkThisInStaticMemberFunctionType(Method); } // Extra checking for C++ overloaded operators (C++ [over.oper]). if (NewFD->isOverloadedOperator() && CheckOverloadedOperatorDeclaration(NewFD)) { NewFD->setInvalidDecl(); return Redeclaration; } // Extra checking for C++0x literal operators (C++0x [over.literal]). if (NewFD->getLiteralIdentifier() && CheckLiteralOperatorDeclaration(NewFD)) { NewFD->setInvalidDecl(); return Redeclaration; } // In C++, check default arguments now that we have merged decls. Unless // the lexical context is the class, because in this case this is done // during delayed parsing anyway. if (!CurContext->isRecord()) CheckCXXDefaultArguments(NewFD); // If this function declares a builtin function, check the type of this // declaration against the expected type for the builtin. if (unsigned BuiltinID = NewFD->getBuiltinID()) { ASTContext::GetBuiltinTypeError Error; LookupPredefedObjCSuperType(*this, S, NewFD->getIdentifier()); QualType T = Context.GetBuiltinType(BuiltinID, Error); if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) { // The type of this function differs from the type of the builtin, // so forget about the builtin entirely. Context.BuiltinInfo.ForgetBuiltin(BuiltinID, Context.Idents); } } // If this function is declared as being extern "C", then check to see if // the function returns a UDT (class, struct, or union type) that is not C // compatible, and if it does, warn the user. // But, issue any diagnostic on the first declaration only. if (NewFD->isExternC() && Previous.empty()) { QualType R = NewFD->getResultType(); if (R->isIncompleteType() && !R->isVoidType()) Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete) << NewFD << R; else if (!R.isPODType(Context) && !R->isVoidType() && !R->isObjCObjectPointerType()) Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R; } } return Redeclaration; } static SourceRange getResultSourceRange(const FunctionDecl *FD) { const TypeSourceInfo *TSI = FD->getTypeSourceInfo(); if (!TSI) return SourceRange(); TypeLoc TL = TSI->getTypeLoc(); FunctionTypeLoc FunctionTL = TL.getAs<FunctionTypeLoc>(); if (!FunctionTL) return SourceRange(); TypeLoc ResultTL = FunctionTL.getResultLoc(); if (ResultTL.getUnqualifiedLoc().getAs<BuiltinTypeLoc>()) return ResultTL.getSourceRange(); return SourceRange(); } void Sema::CheckMain(FunctionDecl* FD, const DeclSpec& DS) { // C++11 [basic.start.main]p3: A program that declares main to be inline, // static or constexpr is ill-formed. // C11 6.7.4p4: In a hosted environment, no function specifier(s) shall // appear in a declaration of main. // static main is not an error under C99, but we should warn about it. // We accept _Noreturn main as an extension. if (FD->getStorageClass() == SC_Static) Diag(DS.getStorageClassSpecLoc(), getLangOpts().CPlusPlus ? diag::err_static_main : diag::warn_static_main) << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc()); if (FD->isInlineSpecified()) Diag(DS.getInlineSpecLoc(), diag::err_inline_main) << FixItHint::CreateRemoval(DS.getInlineSpecLoc()); if (DS.isNoreturnSpecified()) { SourceLocation NoreturnLoc = DS.getNoreturnSpecLoc(); SourceRange NoreturnRange(NoreturnLoc, PP.getLocForEndOfToken(NoreturnLoc)); Diag(NoreturnLoc, diag::ext_noreturn_main); Diag(NoreturnLoc, diag::note_main_remove_noreturn) << FixItHint::CreateRemoval(NoreturnRange); } if (FD->isConstexpr()) { Diag(DS.getConstexprSpecLoc(), diag::err_constexpr_main) << FixItHint::CreateRemoval(DS.getConstexprSpecLoc()); FD->setConstexpr(false); } QualType T = FD->getType(); assert(T->isFunctionType() && "function decl is not of function type"); const FunctionType* FT = T->castAs<FunctionType>(); // All the standards say that main() should should return 'int'. if (Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { // In C and C++, main magically returns 0 if you fall off the end; // set the flag which tells us that. // This is C++ [basic.start.main]p5 and C99 5.1.2.2.3. FD->setHasImplicitReturnZero(true); // In C with GNU extensions we allow main() to have non-integer return // type, but we should warn about the extension, and we disable the // implicit-return-zero rule. } else if (getLangOpts().GNUMode && !getLangOpts().CPlusPlus) { Diag(FD->getTypeSpecStartLoc(), diag::ext_main_returns_nonint); SourceRange ResultRange = getResultSourceRange(FD); if (ResultRange.isValid()) Diag(ResultRange.getBegin(), diag::note_main_change_return_type) << FixItHint::CreateReplacement(ResultRange, "int"); // Otherwise, this is just a flat-out error. } else { SourceRange ResultRange = getResultSourceRange(FD); if (ResultRange.isValid()) Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint) << FixItHint::CreateReplacement(ResultRange, "int"); else Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); FD->setInvalidDecl(true); } // Treat protoless main() as nullary. if (isa<FunctionNoProtoType>(FT)) return; const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); unsigned nparams = FTP->getNumArgs(); assert(FD->getNumParams() == nparams); bool HasExtraParameters = (nparams > 3); // Darwin passes an undocumented fourth argument of type char**. If // other platforms start sprouting these, the logic below will start // getting shifty. if (nparams == 4 && Context.getTargetInfo().getTriple().isOSDarwin()) HasExtraParameters = false; if (HasExtraParameters) { Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; FD->setInvalidDecl(true); nparams = 3; } // FIXME: a lot of the following diagnostics would be improved // if we had some location information about types. QualType CharPP = Context.getPointerType(Context.getPointerType(Context.CharTy)); QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; for (unsigned i = 0; i < nparams; ++i) { QualType AT = FTP->getArgType(i); bool mismatch = true; if (Context.hasSameUnqualifiedType(AT, Expected[i])) mismatch = false; else if (Expected[i] == CharPP) { // As an extension, the following forms are okay: // char const ** // char const * const * // char * const * QualifierCollector qs; const PointerType* PT; if ((PT = qs.strip(AT)->getAs<PointerType>()) && (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && Context.hasSameType(QualType(qs.strip(PT->getPointeeType()), 0), Context.CharTy)) { qs.removeConst(); mismatch = !qs.empty(); } } if (mismatch) { Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; // TODO: suggest replacing given type with expected type FD->setInvalidDecl(true); } } if (nparams == 1 && !FD->isInvalidDecl()) { Diag(FD->getLocation(), diag::warn_main_one_arg); } if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { Diag(FD->getLocation(), diag::err_main_template_decl); FD->setInvalidDecl(); } } bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { // FIXME: Need strict checking. In C89, we need to check for // any assignment, increment, decrement, function-calls, or // commas outside of a sizeof. In C99, it's the same list, // except that the aforementioned are allowed in unevaluated // expressions. Everything else falls under the // "may accept other forms of constant expressions" exception. // (We never end up here for C++, so the constant expression // rules there don't matter.) if (Init->isConstantInitializer(Context, false)) return false; Diag(Init->getExprLoc(), diag::err_init_element_not_constant) << Init->getSourceRange(); return true; } namespace { // Visits an initialization expression to see if OrigDecl is evaluated in // its own initialization and throws a warning if it does. class SelfReferenceChecker : public EvaluatedExprVisitor<SelfReferenceChecker> { Sema &S; Decl *OrigDecl; bool isRecordType; bool isPODType; bool isReferenceType; public: typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited; SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context), S(S), OrigDecl(OrigDecl) { isPODType = false; isRecordType = false; isReferenceType = false; if (ValueDecl *VD = dyn_cast<ValueDecl>(OrigDecl)) { isPODType = VD->getType().isPODType(S.Context); isRecordType = VD->getType()->isRecordType(); isReferenceType = VD->getType()->isReferenceType(); } } // For most expressions, the cast is directly above the DeclRefExpr. // For conditional operators, the cast can be outside the conditional // operator if both expressions are DeclRefExpr's. void HandleValue(Expr *E) { if (isReferenceType) return; E = E->IgnoreParenImpCasts(); if (DeclRefExpr* DRE = dyn_cast<DeclRefExpr>(E)) { HandleDeclRefExpr(DRE); return; } if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) { HandleValue(CO->getTrueExpr()); HandleValue(CO->getFalseExpr()); return; } if (isa<MemberExpr>(E)) { Expr *Base = E->IgnoreParenImpCasts(); while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) { // Check for static member variables and don't warn on them. if (!isa<FieldDecl>(ME->getMemberDecl())) return; Base = ME->getBase()->IgnoreParenImpCasts(); } if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) HandleDeclRefExpr(DRE); return; } } // Reference types are handled here since all uses of references are // bad, not just r-value uses. void VisitDeclRefExpr(DeclRefExpr *E) { if (isReferenceType) HandleDeclRefExpr(E); } void VisitImplicitCastExpr(ImplicitCastExpr *E) { if (E->getCastKind() == CK_LValueToRValue || (isRecordType && E->getCastKind() == CK_NoOp)) HandleValue(E->getSubExpr()); Inherited::VisitImplicitCastExpr(E); } void VisitMemberExpr(MemberExpr *E) { // Don't warn on arrays since they can be treated as pointers. if (E->getType()->canDecayToPointerType()) return; // Warn when a non-static method call is followed by non-static member // field accesses, which is followed by a DeclRefExpr. CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl()); bool Warn = (MD && !MD->isStatic()); Expr *Base = E->getBase()->IgnoreParenImpCasts(); while (MemberExpr *ME = dyn_cast<MemberExpr>(Base)) { if (!isa<FieldDecl>(ME->getMemberDecl())) Warn = false; Base = ME->getBase()->IgnoreParenImpCasts(); } if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) { if (Warn) HandleDeclRefExpr(DRE); return; } // The base of a MemberExpr is not a MemberExpr or a DeclRefExpr. // Visit that expression. Visit(Base); } void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) { if (E->getNumArgs() > 0) if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E->getArg(0))) HandleDeclRefExpr(DRE); Inherited::VisitCXXOperatorCallExpr(E); } void VisitUnaryOperator(UnaryOperator *E) { // For POD record types, addresses of its own members are well-defined. if (E->getOpcode() == UO_AddrOf && isRecordType && isa<MemberExpr>(E->getSubExpr()->IgnoreParens())) { if (!isPODType) HandleValue(E->getSubExpr()); return; } Inherited::VisitUnaryOperator(E); } void VisitObjCMessageExpr(ObjCMessageExpr *E) { return; } void HandleDeclRefExpr(DeclRefExpr *DRE) { Decl* ReferenceDecl = DRE->getDecl(); if (OrigDecl != ReferenceDecl) return; unsigned diag; if (isReferenceType) { diag = diag::warn_uninit_self_reference_in_reference_init; } else if (cast<VarDecl>(OrigDecl)->isStaticLocal()) { diag = diag::warn_static_self_reference_in_init; } else { diag = diag::warn_uninit_self_reference_in_init; } S.DiagRuntimeBehavior(DRE->getLocStart(), DRE, S.PDiag(diag) << DRE->getNameInfo().getName() << OrigDecl->getLocation() << DRE->getSourceRange()); } }; /// CheckSelfReference - Warns if OrigDecl is used in expression E. static void CheckSelfReference(Sema &S, Decl* OrigDecl, Expr *E, bool DirectInit) { // Parameters arguments are occassionially constructed with itself, // for instance, in recursive functions. Skip them. if (isa<ParmVarDecl>(OrigDecl)) return; E = E->IgnoreParens(); // Skip checking T a = a where T is not a record or reference type. // Doing so is a way to silence uninitialized warnings. if (!DirectInit && !cast<VarDecl>(OrigDecl)->getType()->isRecordType()) if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) if (ICE->getCastKind() == CK_LValueToRValue) if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr())) if (DRE->getDecl() == OrigDecl) return; SelfReferenceChecker(S, OrigDecl).Visit(E); } } /// AddInitializerToDecl - Adds the initializer Init to the /// declaration dcl. If DirectInit is true, this is C++ direct /// initialization rather than copy initialization. void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, bool DirectInit, bool TypeMayContainAuto) { // If there is no declaration, there was an error parsing it. Just ignore // the initializer. if (RealDecl == 0 || RealDecl->isInvalidDecl()) return; if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { // With declarators parsed the way they are, the parser cannot // distinguish between a normal initializer and a pure-specifier. // Thus this grotesque test. IntegerLiteral *IL; if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && Context.getCanonicalType(IL->getType()) == Context.IntTy) CheckPureMethod(Method, Init->getSourceRange()); else { Diag(Method->getLocation(), diag::err_member_function_initialization) << Method->getDeclName() << Init->getSourceRange(); Method->setInvalidDecl(); } return; } VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); if (!VDecl) { assert(!isa<FieldDecl>(RealDecl) && "field init shouldn't get here"); Diag(RealDecl->getLocation(), diag::err_illegal_initializer); RealDecl->setInvalidDecl(); return; } ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init); // C++11 [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. if (TypeMayContainAuto && VDecl->getType()->isUndeducedType()) { Expr *DeduceInit = Init; // Initializer could be a C++ direct-initializer. Deduction only works if it // contains exactly one expression. if (CXXDirectInit) { if (CXXDirectInit->getNumExprs() == 0) { // It isn't possible to write this directly, but it is possible to // end up in this situation with "auto x(some_pack...);" Diag(CXXDirectInit->getLocStart(), diag::err_auto_var_init_no_expression) << VDecl->getDeclName() << VDecl->getType() << VDecl->getSourceRange(); RealDecl->setInvalidDecl(); return; } else if (CXXDirectInit->getNumExprs() > 1) { Diag(CXXDirectInit->getExpr(1)->getLocStart(), diag::err_auto_var_init_multiple_expressions) << VDecl->getDeclName() << VDecl->getType() << VDecl->getSourceRange(); RealDecl->setInvalidDecl(); return; } else { DeduceInit = CXXDirectInit->getExpr(0); } } // Expressions default to 'id' when we're in a debugger. bool DefaultedToAuto = false; if (getLangOpts().DebuggerCastResultToId && Init->getType() == Context.UnknownAnyTy) { ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType()); if (Result.isInvalid()) { VDecl->setInvalidDecl(); return; } Init = Result.take(); DefaultedToAuto = true; } QualType DeducedType; if (DeduceAutoType(VDecl->getTypeSourceInfo(), DeduceInit, DeducedType) == DAR_Failed) DiagnoseAutoDeductionFailure(VDecl, DeduceInit); if (DeducedType.isNull()) { RealDecl->setInvalidDecl(); return; } VDecl->setType(DeducedType); assert(VDecl->isLinkageValid()); // In ARC, infer lifetime. if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(VDecl)) VDecl->setInvalidDecl(); // Warn if we deduced 'id'. 'auto' usually implies type-safety, but using // 'id' instead of a specific object type prevents most of our usual checks. // We only want to warn outside of template instantiations, though: // inside a template, the 'id' could have come from a parameter. if (ActiveTemplateInstantiations.empty() && !DefaultedToAuto && DeducedType->isObjCIdType()) { SourceLocation Loc = VDecl->getTypeSourceInfo()->getTypeLoc().getBeginLoc(); Diag(Loc, diag::warn_auto_var_is_id) << VDecl->getDeclName() << DeduceInit->getSourceRange(); } // If this is a redeclaration, check that the type we just deduced matches // the previously declared type. if (VarDecl *Old = VDecl->getPreviousDecl()) MergeVarDeclTypes(VDecl, Old, /*OldWasHidden*/ false); // Check the deduced type is valid for a variable declaration. CheckVariableDeclarationType(VDecl); if (VDecl->isInvalidDecl()) return; } if (VDecl->isLocalVarDecl() && VDecl->hasExternalStorage()) { // C99 6.7.8p5. C++ has no such restriction, but that is a defect. Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); VDecl->setInvalidDecl(); return; } if (!VDecl->getType()->isDependentType()) { // A definition must end up with a complete type, which means it must be // complete with the restriction that an array type might be completed by // the initializer; note that later code assumes this restriction. QualType BaseDeclType = VDecl->getType(); if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) BaseDeclType = Array->getElementType(); if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, diag::err_typecheck_decl_incomplete_type)) { RealDecl->setInvalidDecl(); return; } // The variable can not have an abstract class type. if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), diag::err_abstract_type_in_decl, AbstractVariableType)) VDecl->setInvalidDecl(); } const VarDecl *Def; if ((Def = VDecl->getDefinition()) && Def != VDecl) { Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); Diag(Def->getLocation(), diag::note_previous_definition); VDecl->setInvalidDecl(); return; } const VarDecl* PrevInit = 0; if (getLangOpts().CPlusPlus) { // C++ [class.static.data]p4 // If a static data member is of const integral or const // enumeration type, its declaration in the class definition can // specify a constant-initializer which shall be an integral // constant expression (5.19). In that case, the member can appear // in integral constant expressions. The member shall still be // defined in a namespace scope if it is used in the program and the // namespace scope definition shall not contain an initializer. // // We already performed a redefinition check above, but for static // data members we also need to check whether there was an in-class // declaration with an initializer. if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); Diag(PrevInit->getLocation(), diag::note_previous_definition); return; } if (VDecl->hasLocalStorage()) getCurFunction()->setHasBranchProtectedScope(); if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) { VDecl->setInvalidDecl(); return; } } // OpenCL 1.1 6.5.2: "Variables allocated in the __local address space inside // a kernel function cannot be initialized." if (VDecl->getStorageClass() == SC_OpenCLWorkGroupLocal) { Diag(VDecl->getLocation(), diag::err_local_cant_init); VDecl->setInvalidDecl(); return; } // Get the decls type and save a reference for later, since // CheckInitializerTypes may change it. QualType DclT = VDecl->getType(), SavT = DclT; // Expressions default to 'id' when we're in a debugger // and we are assigning it to a variable of Objective-C pointer type. if (getLangOpts().DebuggerCastResultToId && DclT->isObjCObjectPointerType() && Init->getType() == Context.UnknownAnyTy) { ExprResult Result = forceUnknownAnyToType(Init, Context.getObjCIdType()); if (Result.isInvalid()) { VDecl->setInvalidDecl(); return; } Init = Result.take(); } // Perform the initialization. if (!VDecl->isInvalidDecl()) { InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); InitializationKind Kind = DirectInit ? CXXDirectInit ? InitializationKind::CreateDirect(VDecl->getLocation(), Init->getLocStart(), Init->getLocEnd()) : InitializationKind::CreateDirectList( VDecl->getLocation()) : InitializationKind::CreateCopy(VDecl->getLocation(), Init->getLocStart()); MultiExprArg Args = Init; if (CXXDirectInit) Args = MultiExprArg(CXXDirectInit->getExprs(), CXXDirectInit->getNumExprs()); InitializationSequence InitSeq(*this, Entity, Kind, Args); ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT); if (Result.isInvalid()) { VDecl->setInvalidDecl(); return; } Init = Result.takeAs<Expr>(); } // Check for self-references within variable initializers. // Variables declared within a function/method body (except for references) // are handled by a dataflow analysis. if (!VDecl->hasLocalStorage() || VDecl->getType()->isRecordType() || VDecl->getType()->isReferenceType()) { CheckSelfReference(*this, RealDecl, Init, DirectInit); } // If the type changed, it means we had an incomplete type that was // completed by the initializer. For example: // int ary[] = { 1, 3, 5 }; // "ary" transitions from an IncompleteArrayType to a ConstantArrayType. if (!VDecl->isInvalidDecl() && (DclT != SavT)) VDecl->setType(DclT); if (!VDecl->isInvalidDecl()) { checkUnsafeAssigns(VDecl->getLocation(), VDecl->getType(), Init); if (VDecl->hasAttr<BlocksAttr>()) checkRetainCycles(VDecl, Init); // It is safe to assign a weak reference into a strong variable. // Although this code can still have problems: // id x = self.weakProp; // id y = self.weakProp; // we do not warn to warn spuriously when 'x' and 'y' are on separate // paths through the function. This should be revisited if // -Wrepeated-use-of-weak is made flow-sensitive. if (VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong) { DiagnosticsEngine::Level Level = Diags.getDiagnosticLevel(diag::warn_arc_repeated_use_of_weak, Init->getLocStart()); if (Level != DiagnosticsEngine::Ignored) getCurFunction()->markSafeWeakUse(Init); } } // The initialization is usually a full-expression. // // FIXME: If this is a braced initialization of an aggregate, it is not // an expression, and each individual field initializer is a separate // full-expression. For instance, in: // // struct Temp { ~Temp(); }; // struct S { S(Temp); }; // struct T { S a, b; } t = { Temp(), Temp() } // // we should destroy the first Temp before constructing the second. ExprResult Result = ActOnFinishFullExpr(Init, VDecl->getLocation(), false, VDecl->isConstexpr()); if (Result.isInvalid()) { VDecl->setInvalidDecl(); return; } Init = Result.take(); // Attach the initializer to the decl. VDecl->setInit(Init); if (VDecl->isLocalVarDecl()) { // C99 6.7.8p4: All the expressions in an initializer for an object that has // static storage duration shall be constant expressions or string literals. // C++ does not have this restriction. if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl()) { if (VDecl->getStorageClass() == SC_Static) CheckForConstantInitializer(Init, DclT); // C89 is stricter than C99 for non-static aggregate types. // C89 6.5.7p3: All the expressions [...] in an initializer list // for an object that has aggregate or union type shall be // constant expressions. else if (!getLangOpts().C99 && VDecl->getType()->isAggregateType() && isa<InitListExpr>(Init) && !Init->isConstantInitializer(Context, false)) Diag(Init->getExprLoc(), diag::ext_aggregate_init_not_constant) << Init->getSourceRange(); } } else if (VDecl->isStaticDataMember() && VDecl->getLexicalDeclContext()->isRecord()) { // This is an in-class initialization for a static data member, e.g., // // struct S { // static const int value = 17; // }; // C++ [class.mem]p4: // A member-declarator can contain a constant-initializer only // if it declares a static member (9.4) of const integral or // const enumeration type, see 9.4.2. // // C++11 [class.static.data]p3: // If a non-volatile const static data member is of integral or // enumeration type, its declaration in the class definition can // specify a brace-or-equal-initializer in which every initalizer-clause // that is an assignment-expression is a constant expression. A static // data member of literal type can be declared in the class definition // with the constexpr specifier; if so, its declaration shall specify a // brace-or-equal-initializer in which every initializer-clause that is // an assignment-expression is a constant expression. // Do nothing on dependent types. if (DclT->isDependentType()) { // Allow any 'static constexpr' members, whether or not they are of literal // type. We separately check that every constexpr variable is of literal // type. } else if (VDecl->isConstexpr()) { // Require constness. } else if (!DclT.isConstQualified()) { Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) << Init->getSourceRange(); VDecl->setInvalidDecl(); // We allow integer constant expressions in all cases. } else if (DclT->isIntegralOrEnumerationType()) { // Check whether the expression is a constant expression. SourceLocation Loc; if (getLangOpts().CPlusPlus11 && DclT.isVolatileQualified()) // In C++11, a non-constexpr const static data member with an // in-class initializer cannot be volatile. Diag(VDecl->getLocation(), diag::err_in_class_initializer_volatile); else if (Init->isValueDependent()) ; // Nothing to check. else if (Init->isIntegerConstantExpr(Context, &Loc)) ; // Ok, it's an ICE! else if (Init->isEvaluatable(Context)) { // If we can constant fold the initializer through heroics, accept it, // but report this as a use of an extension for -pedantic. Diag(Loc, diag::ext_in_class_initializer_non_constant) << Init->getSourceRange(); } else { // Otherwise, this is some crazy unknown case. Report the issue at the // location provided by the isIntegerConstantExpr failed check. Diag(Loc, diag::err_in_class_initializer_non_constant) << Init->getSourceRange(); VDecl->setInvalidDecl(); } // We allow foldable floating-point constants as an extension. } else if (DclT->isFloatingType()) { // also permits complex, which is ok // In C++98, this is a GNU extension. In C++11, it is not, but we support // it anyway and provide a fixit to add the 'constexpr'. if (getLangOpts().CPlusPlus11) { Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type_cxx11) << DclT << Init->getSourceRange(); Diag(VDecl->getLocStart(), diag::note_in_class_initializer_float_type_cxx11) << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr "); } else { Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) << DclT << Init->getSourceRange(); if (!Init->isValueDependent() && !Init->isEvaluatable(Context)) { Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) << Init->getSourceRange(); VDecl->setInvalidDecl(); } } // Suggest adding 'constexpr' in C++11 for literal types. } else if (getLangOpts().CPlusPlus11 && DclT->isLiteralType(Context)) { Diag(VDecl->getLocation(), diag::err_in_class_initializer_literal_type) << DclT << Init->getSourceRange() << FixItHint::CreateInsertion(VDecl->getLocStart(), "constexpr "); VDecl->setConstexpr(true); } else { Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) << DclT << Init->getSourceRange(); VDecl->setInvalidDecl(); } } else if (VDecl->isFileVarDecl()) { if (VDecl->getStorageClass() == SC_Extern && (!getLangOpts().CPlusPlus || !(Context.getBaseElementType(VDecl->getType()).isConstQualified() || VDecl->isExternC()))) Diag(VDecl->getLocation(), diag::warn_extern_init); // C99 6.7.8p4. All file scoped initializers need to be constant. if (!getLangOpts().CPlusPlus && !VDecl->isInvalidDecl()) CheckForConstantInitializer(Init, DclT); else if (VDecl->getTLSKind() == VarDecl::TLS_Static && !VDecl->isInvalidDecl() && !DclT->isDependentType() && !Init->isValueDependent() && !VDecl->isConstexpr() && !Init->isConstantInitializer( Context, VDecl->getType()->isReferenceType())) { // GNU C++98 edits for __thread, [basic.start.init]p4: // An object of thread storage duration shall not require dynamic // initialization. // FIXME: Need strict checking here. Diag(VDecl->getLocation(), diag::err_thread_dynamic_init); if (getLangOpts().CPlusPlus11) Diag(VDecl->getLocation(), diag::note_use_thread_local); } } // We will represent direct-initialization similarly to copy-initialization: // int x(1); -as-> int x = 1; // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); // // Clients that want to distinguish between the two forms, can check for // direct initializer using VarDecl::getInitStyle(). // A major benefit is that clients that don't particularly care about which // exactly form was it (like the CodeGen) can handle both cases without // special case code. // C++ 8.5p11: // The form of initialization (using parentheses or '=') is generally // insignificant, but does matter when the entity being initialized has a // class type. if (CXXDirectInit) { assert(DirectInit && "Call-style initializer must be direct init."); VDecl->setInitStyle(VarDecl::CallInit); } else if (DirectInit) { // This must be list-initialization. No other way is direct-initialization. VDecl->setInitStyle(VarDecl::ListInit); } CheckCompleteVariableDeclaration(VDecl); } /// ActOnInitializerError - Given that there was an error parsing an /// initializer for the given declaration, try to return to some form /// of sanity. void Sema::ActOnInitializerError(Decl *D) { // Our main concern here is re-establishing invariants like "a // variable's type is either dependent or complete". if (!D || D->isInvalidDecl()) return; VarDecl *VD = dyn_cast<VarDecl>(D); if (!VD) return; // Auto types are meaningless if we can't make sense of the initializer. if (ParsingInitForAutoVars.count(D)) { D->setInvalidDecl(); return; } QualType Ty = VD->getType(); if (Ty->isDependentType()) return; // Require a complete type. if (RequireCompleteType(VD->getLocation(), Context.getBaseElementType(Ty), diag::err_typecheck_decl_incomplete_type)) { VD->setInvalidDecl(); return; } // Require an abstract type. if (RequireNonAbstractType(VD->getLocation(), Ty, diag::err_abstract_type_in_decl, AbstractVariableType)) { VD->setInvalidDecl(); return; } // Don't bother complaining about constructors or destructors, // though. } void Sema::ActOnUninitializedDecl(Decl *RealDecl, bool TypeMayContainAuto) { // If there is no declaration, there was an error parsing it. Just ignore it. if (RealDecl == 0) return; if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { QualType Type = Var->getType(); // C++11 [dcl.spec.auto]p3 if (TypeMayContainAuto && Type->getContainedAutoType()) { Diag(Var->getLocation(), diag::err_auto_var_requires_init) << Var->getDeclName() << Type; Var->setInvalidDecl(); return; } // C++11 [class.static.data]p3: A static data member can be declared with // the constexpr specifier; if so, its declaration shall specify // a brace-or-equal-initializer. // C++11 [dcl.constexpr]p1: The constexpr specifier shall be applied only to // the definition of a variable [...] or the declaration of a static data // member. if (Var->isConstexpr() && !Var->isThisDeclarationADefinition()) { if (Var->isStaticDataMember()) Diag(Var->getLocation(), diag::err_constexpr_static_mem_var_requires_init) << Var->getDeclName(); else Diag(Var->getLocation(), diag::err_invalid_constexpr_var_decl); Var->setInvalidDecl(); return; } switch (Var->isThisDeclarationADefinition()) { case VarDecl::Definition: if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) break; // We have an out-of-line definition of a static data member // that has an in-class initializer, so we type-check this like // a declaration. // // Fall through case VarDecl::DeclarationOnly: // It's only a declaration. // Block scope. C99 6.7p7: If an identifier for an object is // declared with no linkage (C99 6.2.2p6), the type for the // object shall be complete. if (!Type->isDependentType() && Var->isLocalVarDecl() && !Var->hasLinkage() && !Var->isInvalidDecl() && RequireCompleteType(Var->getLocation(), Type, diag::err_typecheck_decl_incomplete_type)) Var->setInvalidDecl(); // Make sure that the type is not abstract. if (!Type->isDependentType() && !Var->isInvalidDecl() && RequireNonAbstractType(Var->getLocation(), Type, diag::err_abstract_type_in_decl, AbstractVariableType)) Var->setInvalidDecl(); if (!Type->isDependentType() && !Var->isInvalidDecl() && Var->getStorageClass() == SC_PrivateExtern) { Diag(Var->getLocation(), diag::warn_private_extern); Diag(Var->getLocation(), diag::note_private_extern); } return; case VarDecl::TentativeDefinition: // File scope. C99 6.9.2p2: A declaration of an identifier for an // object that has file scope without an initializer, and without a // storage-class specifier or with the storage-class specifier "static", // constitutes a tentative definition. Note: A tentative definition with // external linkage is valid (C99 6.2.2p5). if (!Var->isInvalidDecl()) { if (const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(Type)) { if (RequireCompleteType(Var->getLocation(), ArrayT->getElementType(), diag::err_illegal_decl_array_incomplete_type)) Var->setInvalidDecl(); } else if (Var->getStorageClass() == SC_Static) { // C99 6.9.2p3: If the declaration of an identifier for an object is // a tentative definition and has internal linkage (C99 6.2.2p3), the // declared type shall not be an incomplete type. // NOTE: code such as the following // static struct s; // struct s { int a; }; // is accepted by gcc. Hence here we issue a warning instead of // an error and we do not invalidate the static declaration. // NOTE: to avoid multiple warnings, only check the first declaration. if (Var->getPreviousDecl() == 0) RequireCompleteType(Var->getLocation(), Type, diag::ext_typecheck_decl_incomplete_type); } } // Record the tentative definition; we're done. if (!Var->isInvalidDecl()) TentativeDefinitions.push_back(Var); return; } // Provide a specific diagnostic for uninitialized variable // definitions with incomplete array type. if (Type->isIncompleteArrayType()) { Diag(Var->getLocation(), diag::err_typecheck_incomplete_array_needs_initializer); Var->setInvalidDecl(); return; } // Provide a specific diagnostic for uninitialized variable // definitions with reference type. if (Type->isReferenceType()) { Diag(Var->getLocation(), diag::err_reference_var_requires_init) << Var->getDeclName() << SourceRange(Var->getLocation(), Var->getLocation()); Var->setInvalidDecl(); return; } // Do not attempt to type-check the default initializer for a // variable with dependent type. if (Type->isDependentType()) return; if (Var->isInvalidDecl()) return; if (RequireCompleteType(Var->getLocation(), Context.getBaseElementType(Type), diag::err_typecheck_decl_incomplete_type)) { Var->setInvalidDecl(); return; } // The variable can not have an abstract class type. if (RequireNonAbstractType(Var->getLocation(), Type, diag::err_abstract_type_in_decl, AbstractVariableType)) { Var->setInvalidDecl(); return; } // Check for jumps past the implicit initializer. C++0x // clarifies that this applies to a "variable with automatic // storage duration", not a "local variable". // C++11 [stmt.dcl]p3 // A program that jumps from a point where a variable with automatic // storage duration is not in scope to a point where it is in scope is // ill-formed unless the variable has scalar type, class type with a // trivial default constructor and a trivial destructor, a cv-qualified // version of one of these types, or an array of one of the preceding // types and is declared without an initializer. if (getLangOpts().CPlusPlus && Var->hasLocalStorage()) { if (const RecordType *Record = Context.getBaseElementType(Type)->getAs<RecordType>()) { CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record->getDecl()); // Mark the function for further checking even if the looser rules of // C++11 do not require such checks, so that we can diagnose // incompatibilities with C++98. if (!CXXRecord->isPOD()) getCurFunction()->setHasBranchProtectedScope(); } } // C++03 [dcl.init]p9: // If no initializer is specified for an object, and the // object is of (possibly cv-qualified) non-POD class type (or // array thereof), the object shall be default-initialized; if // the object is of const-qualified type, the underlying class // type shall have a user-declared default // constructor. Otherwise, if no initializer is specified for // a non- static object, the object and its subobjects, if // any, have an indeterminate initial value); if the object // or any of its subobjects are of const-qualified type, the // program is ill-formed. // C++0x [dcl.init]p11: // If no initializer is specified for an object, the object is // default-initialized; [...]. InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); InitializationKind Kind = InitializationKind::CreateDefault(Var->getLocation()); InitializationSequence InitSeq(*this, Entity, Kind, None); ExprResult Init = InitSeq.Perform(*this, Entity, Kind, None); if (Init.isInvalid()) Var->setInvalidDecl(); else if (Init.get()) { Var->setInit(MaybeCreateExprWithCleanups(Init.get())); // This is important for template substitution. Var->setInitStyle(VarDecl::CallInit); } CheckCompleteVariableDeclaration(Var); } } void Sema::ActOnCXXForRangeDecl(Decl *D) { VarDecl *VD = dyn_cast<VarDecl>(D); if (!VD) { Diag(D->getLocation(), diag::err_for_range_decl_must_be_var); D->setInvalidDecl(); return; } VD->setCXXForRangeDecl(true); // for-range-declaration cannot be given a storage class specifier. int Error = -1; switch (VD->getStorageClass()) { case SC_None: break; case SC_Extern: Error = 0; break; case SC_Static: Error = 1; break; case SC_PrivateExtern: Error = 2; break; case SC_Auto: Error = 3; break; case SC_Register: Error = 4; break; case SC_OpenCLWorkGroupLocal: llvm_unreachable("Unexpected storage class"); } if (VD->isConstexpr()) Error = 5; if (Error != -1) { Diag(VD->getOuterLocStart(), diag::err_for_range_storage_class) << VD->getDeclName() << Error; D->setInvalidDecl(); } } void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { if (var->isInvalidDecl()) return; // In ARC, don't allow jumps past the implicit initialization of a // local retaining variable. if (getLangOpts().ObjCAutoRefCount && var->hasLocalStorage()) { switch (var->getType().getObjCLifetime()) { case Qualifiers::OCL_None: case Qualifiers::OCL_ExplicitNone: case Qualifiers::OCL_Autoreleasing: break; case Qualifiers::OCL_Weak: case Qualifiers::OCL_Strong: getCurFunction()->setHasBranchProtectedScope(); break; } } if (var->isThisDeclarationADefinition() && var->isExternallyVisible() && getDiagnostics().getDiagnosticLevel( diag::warn_missing_variable_declarations, var->getLocation())) { // Find a previous declaration that's not a definition. VarDecl *prev = var->getPreviousDecl(); while (prev && prev->isThisDeclarationADefinition()) prev = prev->getPreviousDecl(); if (!prev) Diag(var->getLocation(), diag::warn_missing_variable_declarations) << var; } if (var->getTLSKind() == VarDecl::TLS_Static && var->getType().isDestructedType()) { // GNU C++98 edits for __thread, [basic.start.term]p3: // The type of an object with thread storage duration shall not // have a non-trivial destructor. Diag(var->getLocation(), diag::err_thread_nontrivial_dtor); if (getLangOpts().CPlusPlus11) Diag(var->getLocation(), diag::note_use_thread_local); } // All the following checks are C++ only. if (!getLangOpts().CPlusPlus) return; QualType type = var->getType(); if (type->isDependentType()) return; // __block variables might require us to capture a copy-initializer. if (var->hasAttr<BlocksAttr>()) { // It's currently invalid to ever have a __block variable with an // array type; should we diagnose that here? // Regardless, we don't want to ignore array nesting when // constructing this copy. if (type->isStructureOrClassType()) { EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated); SourceLocation poi = var->getLocation(); Expr *varRef =new (Context) DeclRefExpr(var, false, type, VK_LValue, poi); ExprResult result = PerformMoveOrCopyInitialization( InitializedEntity::InitializeBlock(poi, type, false), var, var->getType(), varRef, /*AllowNRVO=*/true); if (!result.isInvalid()) { result = MaybeCreateExprWithCleanups(result); Expr *init = result.takeAs<Expr>(); Context.setBlockVarCopyInits(var, init); } } } Expr *Init = var->getInit(); bool IsGlobal = var->hasGlobalStorage() && !var->isStaticLocal(); QualType baseType = Context.getBaseElementType(type); if (!var->getDeclContext()->isDependentContext() && Init && !Init->isValueDependent()) { if (IsGlobal && !var->isConstexpr() && getDiagnostics().getDiagnosticLevel(diag::warn_global_constructor, var->getLocation()) != DiagnosticsEngine::Ignored) { // Warn about globals which don't have a constant initializer. Don't // warn about globals with a non-trivial destructor because we already // warned about them. CXXRecordDecl *RD = baseType->getAsCXXRecordDecl(); if (!(RD && !RD->hasTrivialDestructor()) && !Init->isConstantInitializer(Context, baseType->isReferenceType())) Diag(var->getLocation(), diag::warn_global_constructor) << Init->getSourceRange(); } if (var->isConstexpr()) { SmallVector<PartialDiagnosticAt, 8> Notes; if (!var->evaluateValue(Notes) || !var->isInitICE()) { SourceLocation DiagLoc = var->getLocation(); // If the note doesn't add any useful information other than a source // location, fold it into the primary diagnostic. if (Notes.size() == 1 && Notes[0].second.getDiagID() == diag::note_invalid_subexpr_in_const_expr) { DiagLoc = Notes[0].first; Notes.clear(); } Diag(DiagLoc, diag::err_constexpr_var_requires_const_init) << var << Init->getSourceRange(); for (unsigned I = 0, N = Notes.size(); I != N; ++I) Diag(Notes[I].first, Notes[I].second); } } else if (var->isUsableInConstantExpressions(Context)) { // Check whether the initializer of a const variable of integral or // enumeration type is an ICE now, since we can't tell whether it was // initialized by a constant expression if we check later. var->checkInitIsICE(); } } // Require the destructor. if (const RecordType *recordType = baseType->getAs<RecordType>()) FinalizeVarWithDestructor(var, recordType); } /// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform /// any semantic actions necessary after any initializer has been attached. void Sema::FinalizeDeclaration(Decl *ThisDecl) { // Note that we are no longer parsing the initializer for this declaration. ParsingInitForAutoVars.erase(ThisDecl); VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDecl); if (!VD) return; const DeclContext *DC = VD->getDeclContext(); // If there's a #pragma GCC visibility in scope, and this isn't a class // member, set the visibility of this variable. if (!DC->isRecord() && VD->isExternallyVisible()) AddPushedVisibilityAttribute(VD); if (VD->isFileVarDecl()) MarkUnusedFileScopedDecl(VD); // Now we have parsed the initializer and can update the table of magic // tag values. if (!VD->hasAttr<TypeTagForDatatypeAttr>() || !VD->getType()->isIntegralOrEnumerationType()) return; for (specific_attr_iterator<TypeTagForDatatypeAttr> I = ThisDecl->specific_attr_begin<TypeTagForDatatypeAttr>(), E = ThisDecl->specific_attr_end<TypeTagForDatatypeAttr>(); I != E; ++I) { const Expr *MagicValueExpr = VD->getInit(); if (!MagicValueExpr) { continue; } llvm::APSInt MagicValueInt; if (!MagicValueExpr->isIntegerConstantExpr(MagicValueInt, Context)) { Diag(I->getRange().getBegin(), diag::err_type_tag_for_datatype_not_ice) << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange(); continue; } if (MagicValueInt.getActiveBits() > 64) { Diag(I->getRange().getBegin(), diag::err_type_tag_for_datatype_too_large) << LangOpts.CPlusPlus << MagicValueExpr->getSourceRange(); continue; } uint64_t MagicValue = MagicValueInt.getZExtValue(); RegisterTypeTagForDatatype(I->getArgumentKind(), MagicValue, I->getMatchingCType(), I->getLayoutCompatible(), I->getMustBeNull()); } } Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, ArrayRef<Decl *> Group) { SmallVector<Decl*, 8> Decls; if (DS.isTypeSpecOwned()) Decls.push_back(DS.getRepAsDecl()); for (unsigned i = 0, e = Group.size(); i != e; ++i) if (Decl *D = Group[i]) Decls.push_back(D); if (DeclSpec::isDeclRep(DS.getTypeSpecType())) { if (const TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) HandleTagNumbering(*this, Tag); } return BuildDeclaratorGroup(Decls, DS.containsPlaceholderType()); } /// BuildDeclaratorGroup - convert a list of declarations into a declaration /// group, performing any necessary semantic checking. Sema::DeclGroupPtrTy Sema::BuildDeclaratorGroup(llvm::MutableArrayRef<Decl *> Group, bool TypeMayContainAuto) { // C++0x [dcl.spec.auto]p7: // If the type deduced for the template parameter U is not the same in each // deduction, the program is ill-formed. // FIXME: When initializer-list support is added, a distinction is needed // between the deduced type U and the deduced type which 'auto' stands for. // auto a = 0, b = { 1, 2, 3 }; // is legal because the deduced type U is 'int' in both cases. if (TypeMayContainAuto && Group.size() > 1) { QualType Deduced; CanQualType DeducedCanon; VarDecl *DeducedDecl = 0; for (unsigned i = 0, e = Group.size(); i != e; ++i) { if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) { AutoType *AT = D->getType()->getContainedAutoType(); // Don't reissue diagnostics when instantiating a template. if (AT && D->isInvalidDecl()) break; QualType U = AT ? AT->getDeducedType() : QualType(); if (!U.isNull()) { CanQualType UCanon = Context.getCanonicalType(U); if (Deduced.isNull()) { Deduced = U; DeducedCanon = UCanon; DeducedDecl = D; } else if (DeducedCanon != UCanon) { Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(), diag::err_auto_different_deductions) << (AT->isDecltypeAuto() ? 1 : 0) << Deduced << DeducedDecl->getDeclName() << U << D->getDeclName() << DeducedDecl->getInit()->getSourceRange() << D->getInit()->getSourceRange(); D->setInvalidDecl(); break; } } } } } ActOnDocumentableDecls(Group); return DeclGroupPtrTy::make( DeclGroupRef::Create(Context, Group.data(), Group.size())); } void Sema::ActOnDocumentableDecl(Decl *D) { ActOnDocumentableDecls(D); } void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) { // Don't parse the comment if Doxygen diagnostics are ignored. if (Group.empty() || !Group[0]) return; if (Diags.getDiagnosticLevel(diag::warn_doc_param_not_found, Group[0]->getLocation()) == DiagnosticsEngine::Ignored) return; if (Group.size() >= 2) { // This is a decl group. Normally it will contain only declarations // produced from declarator list. But in case we have any definitions or // additional declaration references: // 'typedef struct S {} S;' // 'typedef struct S *S;' // 'struct S *pS;' // FinalizeDeclaratorGroup adds these as separate declarations. Decl *MaybeTagDecl = Group[0]; if (MaybeTagDecl && isa<TagDecl>(MaybeTagDecl)) { Group = Group.slice(1); } } // See if there are any new comments that are not attached to a decl. ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments(); if (!Comments.empty() && !Comments.back()->isAttached()) { // There is at least one comment that not attached to a decl. // Maybe it should be attached to one of these decls? // // Note that this way we pick up not only comments that precede the // declaration, but also comments that *follow* the declaration -- thanks to // the lookahead in the lexer: we've consumed the semicolon and looked // ahead through comments. for (unsigned i = 0, e = Group.size(); i != e; ++i) Context.getCommentForDecl(Group[i], &PP); } } /// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() /// to introduce parameters into function prototype scope. Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { const DeclSpec &DS = D.getDeclSpec(); // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. // C++03 [dcl.stc]p2 also permits 'auto'. VarDecl::StorageClass StorageClass = SC_None; if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { StorageClass = SC_Register; } else if (getLangOpts().CPlusPlus && DS.getStorageClassSpec() == DeclSpec::SCS_auto) { StorageClass = SC_Auto; } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { Diag(DS.getStorageClassSpecLoc(), diag::err_invalid_storage_class_in_func_decl); D.getMutableDeclSpec().ClearStorageClassSpecs(); } if (DeclSpec::TSCS TSCS = DS.getThreadStorageClassSpec()) Diag(DS.getThreadStorageClassSpecLoc(), diag::err_invalid_thread) << DeclSpec::getSpecifierName(TSCS); if (DS.isConstexprSpecified()) Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr) << 0; DiagnoseFunctionSpecifiers(DS); TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); QualType parmDeclType = TInfo->getType(); if (getLangOpts().CPlusPlus) { // Check that there are no default arguments inside the type of this // parameter. CheckExtraCXXDefaultArguments(D); // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). if (D.getCXXScopeSpec().isSet()) { Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) << D.getCXXScopeSpec().getRange(); D.getCXXScopeSpec().clear(); } } // Ensure we have a valid name IdentifierInfo *II = 0; if (D.hasName()) { II = D.getIdentifier(); if (!II) { Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name) << GetNameForDeclarator(D).getName().getAsString(); D.setInvalidType(true); } } // Check for redeclaration of parameters, e.g. int foo(int x, int x); if (II) { LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, ForRedeclaration); LookupName(R, S); if (R.isSingleResult()) { NamedDecl *PrevDecl = R.getFoundDecl(); if (PrevDecl->isTemplateParameter()) { // Maybe we will complain about the shadowed template parameter. DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); // Just pretend that we didn't see the previous declaration. PrevDecl = 0; } else if (S->isDeclScope(PrevDecl)) { Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; Diag(PrevDecl->getLocation(), diag::note_previous_declaration); // Recover by removing the name II = 0; D.SetIdentifier(0, D.getIdentifierLoc()); D.setInvalidType(true); } } } // Temporarily put parameter variables in the translation unit, not // the enclosing context. This prevents them from accidentally // looking like class members in C++. ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), D.getLocStart(), D.getIdentifierLoc(), II, parmDeclType, TInfo, StorageClass); if (D.isInvalidType()) New->setInvalidDecl(); assert(S->isFunctionPrototypeScope()); assert(S->getFunctionPrototypeDepth() >= 1); New->setScopeInfo(S->getFunctionPrototypeDepth() - 1, S->getNextFunctionPrototypeIndex()); // Add the parameter declaration into this scope. S->AddDecl(New); if (II) IdResolver.AddDecl(New); ProcessDeclAttributes(S, New, D); if (D.getDeclSpec().isModulePrivateSpecified()) Diag(New->getLocation(), diag::err_module_private_local) << 1 << New->getDeclName() << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc()) << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc()); if (New->hasAttr<BlocksAttr>()) { Diag(New->getLocation(), diag::err_block_on_nonlocal); } return New; } /// \brief Synthesizes a variable for a parameter arising from a /// typedef. ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, SourceLocation Loc, QualType T) { /* FIXME: setting StartLoc == Loc. Would it be worth to modify callers so as to provide proper source location for the unnamed parameters, embedding the parameter's type? */ ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, 0, T, Context.getTrivialTypeSourceInfo(T, Loc), SC_None, 0); Param->setImplicit(); return Param; } void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, ParmVarDecl * const *ParamEnd) { // Don't diagnose unused-parameter errors in template instantiations; we // will already have done so in the template itself. if (!ActiveTemplateInstantiations.empty()) return; for (; Param != ParamEnd; ++Param) { if (!(*Param)->isReferenced() && (*Param)->getDeclName() && !(*Param)->hasAttr<UnusedAttr>()) { Diag((*Param)->getLocation(), diag::warn_unused_parameter) << (*Param)->getDeclName(); } } } void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param, ParmVarDecl * const *ParamEnd, QualType ReturnTy, NamedDecl *D) { if (LangOpts.NumLargeByValueCopy == 0) // No check. return; // Warn if the return value is pass-by-value and larger than the specified // threshold. if (!ReturnTy->isDependentType() && ReturnTy.isPODType(Context)) { unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity(); if (Size > LangOpts.NumLargeByValueCopy) Diag(D->getLocation(), diag::warn_return_value_size) << D->getDeclName() << Size; } // Warn if any parameter is pass-by-value and larger than the specified // threshold. for (; Param != ParamEnd; ++Param) { QualType T = (*Param)->getType(); if (T->isDependentType() || !T.isPODType(Context)) continue; unsigned Size = Context.getTypeSizeInChars(T).getQuantity(); if (Size > LangOpts.NumLargeByValueCopy) Diag((*Param)->getLocation(), diag::warn_parameter_size) << (*Param)->getDeclName() << Size; } } ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc, SourceLocation NameLoc, IdentifierInfo *Name, QualType T, TypeSourceInfo *TSInfo, VarDecl::StorageClass StorageClass) { // In ARC, infer a lifetime qualifier for appropriate parameter types. if (getLangOpts().ObjCAutoRefCount && T.getObjCLifetime() == Qualifiers::OCL_None && T->isObjCLifetimeType()) { Qualifiers::ObjCLifetime lifetime; // Special cases for arrays: // - if it's const, use __unsafe_unretained // - otherwise, it's an error if (T->isArrayType()) { if (!T.isConstQualified()) { DelayedDiagnostics.add( sema::DelayedDiagnostic::makeForbiddenType( NameLoc, diag::err_arc_array_param_no_ownership, T, false)); } lifetime = Qualifiers::OCL_ExplicitNone; } else { lifetime = T->getObjCARCImplicitLifetime(); } T = Context.getLifetimeQualifiedType(T, lifetime); } ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name, Context.getAdjustedParameterType(T), TSInfo, StorageClass, 0); // Parameters can not be abstract class types. // For record types, this is done by the AbstractClassUsageDiagnoser once // the class has been completely parsed. if (!CurContext->isRecord() && RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, AbstractParamType)) New->setInvalidDecl(); // Parameter declarators cannot be interface types. All ObjC objects are // passed by reference. if (T->isObjCObjectType()) { SourceLocation TypeEndLoc = TSInfo->getTypeLoc().getLocEnd(); Diag(NameLoc, diag::err_object_cannot_be_passed_returned_by_value) << 1 << T << FixItHint::CreateInsertion(TypeEndLoc, "*"); T = Context.getObjCObjectPointerType(T); New->setType(T); } // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage // duration shall not be qualified by an address-space qualifier." // Since all parameters have automatic store duration, they can not have // an address space. if (T.getAddressSpace() != 0) { Diag(NameLoc, diag::err_arg_with_address_space); New->setInvalidDecl(); } return New; } void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, SourceLocation LocAfterDecls) { DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' // for a K&R function. if (!FTI.hasPrototype) { for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { --i; if (FTI.ArgInfo[i].Param == 0) { SmallString<256> Code; llvm::raw_svector_ostream(Code) << " int " << FTI.ArgInfo[i].Ident->getName() << ";\n"; Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) << FTI.ArgInfo[i].Ident << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); // Implicitly declare the argument as type 'int' for lack of a better // type. AttributeFactory attrs; DeclSpec DS(attrs); const char* PrevSpec; // unused unsigned DiagID; // unused DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, PrevSpec, DiagID); // Use the identifier location for the type source range. DS.SetRangeStart(FTI.ArgInfo[i].IdentLoc); DS.SetRangeEnd(FTI.ArgInfo[i].IdentLoc); Declarator ParamD(DS, Declarator::KNRTypeListContext); ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); } } } } Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { assert(getCurFunctionDecl() == 0 && "Function parsing confused"); assert(D.isFunctionDeclarator() && "Not a function declarator!"); Scope *ParentScope = FnBodyScope->getParent(); D.setFunctionDefinitionKind(FDK_Definition); Decl *DP = HandleDeclarator(ParentScope, D, MultiTemplateParamsArg()); return ActOnStartOfFunctionDef(FnBodyScope, DP); } static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD, const FunctionDecl*& PossibleZeroParamPrototype) { // Don't warn about invalid declarations. if (FD->isInvalidDecl()) return false; // Or declarations that aren't global. if (!FD->isGlobal()) return false; // Don't warn about C++ member functions. if (isa<CXXMethodDecl>(FD)) return false; // Don't warn about 'main'. if (FD->isMain()) return false; // Don't warn about inline functions. if (FD->isInlined()) return false; // Don't warn about function templates. if (FD->getDescribedFunctionTemplate()) return false; // Don't warn about function template specializations. if (FD->isFunctionTemplateSpecialization()) return false; // Don't warn for OpenCL kernels. if (FD->hasAttr<OpenCLKernelAttr>()) return false; bool MissingPrototype = true; for (const FunctionDecl *Prev = FD->getPreviousDecl(); Prev; Prev = Prev->getPreviousDecl()) { // Ignore any declarations that occur in function or method // scope, because they aren't visible from the header. if (Prev->getDeclContext()->isFunctionOrMethod()) continue; MissingPrototype = !Prev->getType()->isFunctionProtoType(); if (FD->getNumParams() == 0) PossibleZeroParamPrototype = Prev; break; } return MissingPrototype; } void Sema::CheckForFunctionRedefinition(FunctionDecl *FD) { // Don't complain if we're in GNU89 mode and the previous definition // was an extern inline function. const FunctionDecl *Definition; if (FD->isDefined(Definition) && !canRedefineFunction(Definition, getLangOpts())) { if (getLangOpts().GNUMode && Definition->isInlineSpecified() && Definition->getStorageClass() == SC_Extern) Diag(FD->getLocation(), diag::err_redefinition_extern_inline) << FD->getDeclName() << getLangOpts().CPlusPlus; else Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); Diag(Definition->getLocation(), diag::note_previous_definition); FD->setInvalidDecl(); } } Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { // Clear the last template instantiation error context. LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); if (!D) return D; FunctionDecl *FD = 0; if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) FD = FunTmpl->getTemplatedDecl(); else FD = cast<FunctionDecl>(D); // Enter a new function scope PushFunctionScope(); // See if this is a redefinition. if (!FD->isLateTemplateParsed()) CheckForFunctionRedefinition(FD); // Builtin functions cannot be defined. if (unsigned BuiltinID = FD->getBuiltinID()) { if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID) && !Context.BuiltinInfo.isPredefinedRuntimeFunction(BuiltinID)) { Diag(FD->getLocation(), diag::err_builtin_definition) << FD; FD->setInvalidDecl(); } } // The return type of a function definition must be complete // (C99 6.9.1p3, C++ [dcl.fct]p6). QualType ResultType = FD->getResultType(); if (!ResultType->isDependentType() && !ResultType->isVoidType() && !FD->isInvalidDecl() && RequireCompleteType(FD->getLocation(), ResultType, diag::err_func_def_incomplete_result)) FD->setInvalidDecl(); // GNU warning -Wmissing-prototypes: // Warn if a global function is defined without a previous // prototype declaration. This warning is issued even if the // definition itself provides a prototype. The aim is to detect // global functions that fail to be declared in header files. const FunctionDecl *PossibleZeroParamPrototype = 0; if (ShouldWarnAboutMissingPrototype(FD, PossibleZeroParamPrototype)) { Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; if (PossibleZeroParamPrototype) { // We found a declaration that is not a prototype, // but that could be a zero-parameter prototype if (TypeSourceInfo *TI = PossibleZeroParamPrototype->getTypeSourceInfo()) { TypeLoc TL = TI->getTypeLoc(); if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>()) Diag(PossibleZeroParamPrototype->getLocation(), diag::note_declaration_not_a_prototype) << PossibleZeroParamPrototype << FixItHint::CreateInsertion(FTL.getRParenLoc(), "void"); } } } if (FnBodyScope) PushDeclContext(FnBodyScope, FD); // Check the validity of our function parameters CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(), /*CheckParameterNames=*/true); // Introduce our parameters into the function scope for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { ParmVarDecl *Param = FD->getParamDecl(p); Param->setOwningFunction(FD); // If this has an identifier, add it to the scope stack. if (Param->getIdentifier() && FnBodyScope) { CheckShadow(FnBodyScope, Param); PushOnScopeChains(Param, FnBodyScope); } } // If we had any tags defined in the function prototype, // introduce them into the function scope. if (FnBodyScope) { for (llvm::ArrayRef<NamedDecl*>::iterator I = FD->getDeclsInPrototypeScope().begin(), E = FD->getDeclsInPrototypeScope().end(); I != E; ++I) { NamedDecl *D = *I; // Some of these decls (like enums) may have been pinned to the translation unit // for lack of a real context earlier. If so, remove from the translation unit // and reattach to the current context. if (D->getLexicalDeclContext() == Context.getTranslationUnitDecl()) { // Is the decl actually in the context? for (DeclContext::decl_iterator DI = Context.getTranslationUnitDecl()->decls_begin(), DE = Context.getTranslationUnitDecl()->decls_end(); DI != DE; ++DI) { if (*DI == D) { Context.getTranslationUnitDecl()->removeDecl(D); break; } } // Either way, reassign the lexical decl context to our FunctionDecl. D->setLexicalDeclContext(CurContext); } // If the decl has a non-null name, make accessible in the current scope. if (!D->getName().empty()) PushOnScopeChains(D, FnBodyScope, /*AddToContext=*/false); // Similarly, dive into enums and fish their constants out, making them // accessible in this scope. if (EnumDecl *ED = dyn_cast<EnumDecl>(D)) { for (EnumDecl::enumerator_iterator EI = ED->enumerator_begin(), EE = ED->enumerator_end(); EI != EE; ++EI) PushOnScopeChains(*EI, FnBodyScope, /*AddToContext=*/false); } } } // Ensure that the function's exception specification is instantiated. if (const FunctionProtoType *FPT = FD->getType()->getAs<FunctionProtoType>()) ResolveExceptionSpec(D->getLocation(), FPT); // Checking attributes of current function definition // dllimport attribute. DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); if (DA && (!FD->getAttr<DLLExportAttr>())) { // dllimport attribute cannot be directly applied to definition. // Microsoft accepts dllimport for functions defined within class scope. if (!DA->isInherited() && !(LangOpts.MicrosoftExt && FD->getLexicalDeclContext()->isRecord())) { Diag(FD->getLocation(), diag::err_attribute_can_be_applied_only_to_symbol_declaration) << "dllimport"; FD->setInvalidDecl(); return D; } // Visual C++ appears to not think this is an issue, so only issue // a warning when Microsoft extensions are disabled. if (!LangOpts.MicrosoftExt) { // If a symbol previously declared dllimport is later defined, the // attribute is ignored in subsequent references, and a warning is // emitted. Diag(FD->getLocation(), diag::warn_redeclaration_without_attribute_prev_attribute_ignored) << FD->getName() << "dllimport"; } } // We want to attach documentation to original Decl (which might be // a function template). ActOnDocumentableDecl(D); return D; } /// \brief Given the set of return statements within a function body, /// compute the variables that are subject to the named return value /// optimization. /// /// Each of the variables that is subject to the named return value /// optimization will be marked as NRVO variables in the AST, and any /// return statement that has a marked NRVO variable as its NRVO candidate can /// use the named return value optimization. /// /// This function applies a very simplistic algorithm for NRVO: if every return /// statement in the function has the same NRVO candidate, that candidate is /// the NRVO variable. /// /// FIXME: Employ a smarter algorithm that accounts for multiple return /// statements and the lifetimes of the NRVO candidates. We should be able to /// find a maximal set of NRVO variables. void Sema::computeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { ReturnStmt **Returns = Scope->Returns.data(); const VarDecl *NRVOCandidate = 0; for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { if (!Returns[I]->getNRVOCandidate()) return; if (!NRVOCandidate) NRVOCandidate = Returns[I]->getNRVOCandidate(); else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) return; } if (NRVOCandidate) const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); } bool Sema::canSkipFunctionBody(Decl *D) { if (!Consumer.shouldSkipFunctionBody(D)) return false; if (isa<ObjCMethodDecl>(D)) return true; FunctionDecl *FD = 0; if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(D)) FD = FTD->getTemplatedDecl(); else FD = cast<FunctionDecl>(D); // We cannot skip the body of a function (or function template) which is // constexpr, since we may need to evaluate its body in order to parse the // rest of the file. // We cannot skip the body of a function with an undeduced return type, // because any callers of that function need to know the type. return !FD->isConstexpr() && !FD->getResultType()->isUndeducedType(); } Decl *Sema::ActOnSkippedFunctionBody(Decl *Decl) { if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(Decl)) FD->setHasSkippedBody(); else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(Decl)) MD->setHasSkippedBody(); return ActOnFinishFunctionBody(Decl, 0); } Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { return ActOnFinishFunctionBody(D, BodyArg, false); } Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, bool IsInstantiation) { FunctionDecl *FD = 0; FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); if (FunTmpl) FD = FunTmpl->getTemplatedDecl(); else FD = dyn_cast_or_null<FunctionDecl>(dcl); sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); sema::AnalysisBasedWarnings::Policy *ActivePolicy = 0; if (FD) { FD->setBody(Body); if (getLangOpts().CPlusPlus1y && !FD->isInvalidDecl() && Body && !FD->isDependentContext() && FD->getResultType()->isUndeducedType()) { // If the function has a deduced result type but contains no 'return' // statements, the result type as written must be exactly 'auto', and // the deduced result type is 'void'. if (!FD->getResultType()->getAs<AutoType>()) { Diag(dcl->getLocation(), diag::err_auto_fn_no_return_but_not_auto) << FD->getResultType(); FD->setInvalidDecl(); } else { // Substitute 'void' for the 'auto' in the type. TypeLoc ResultType = FD->getTypeSourceInfo()->getTypeLoc(). IgnoreParens().castAs<FunctionProtoTypeLoc>().getResultLoc(); Context.adjustDeducedFunctionResultType( FD, SubstAutoType(ResultType.getType(), Context.VoidTy)); } } // The only way to be included in UndefinedButUsed is if there is an // ODR use before the definition. Avoid the expensive map lookup if this // is the first declaration. if (FD->getPreviousDecl() != 0 && FD->getPreviousDecl()->isUsed()) { if (!FD->isExternallyVisible()) UndefinedButUsed.erase(FD); else if (FD->isInlined() && (LangOpts.CPlusPlus || !LangOpts.GNUInline) && (!FD->getPreviousDecl()->hasAttr<GNUInlineAttr>())) UndefinedButUsed.erase(FD); } // If the function implicitly returns zero (like 'main') or is naked, // don't complain about missing return statements. if (FD->hasImplicitReturnZero() || FD->hasAttr<NakedAttr>()) WP.disableCheckFallThrough(); // MSVC permits the use of pure specifier (=0) on function definition, // defined at class scope, warn about this non standard construct. if (getLangOpts().MicrosoftExt && FD->isPure()) Diag(FD->getLocation(), diag::warn_pure_function_definition); if (!FD->isInvalidDecl()) { DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(), FD->getResultType(), FD); // If this is a constructor, we need a vtable. if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) MarkVTableUsed(FD->getLocation(), Constructor->getParent()); // Try to apply the named return value optimization. We have to check // if we can do this here because lambdas keep return statements around // to deduce an implicit return type. if (getLangOpts().CPlusPlus && FD->getResultType()->isRecordType() && !FD->isDependentContext()) computeNRVO(Body, getCurFunction()); } assert((FD == getCurFunctionDecl() || getCurLambda()->CallOperator == FD) && "Function parsing confused"); } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { assert(MD == getCurMethodDecl() && "Method parsing confused"); MD->setBody(Body); if (!MD->isInvalidDecl()) { DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(), MD->getResultType(), MD); if (Body) computeNRVO(Body, getCurFunction()); } if (getCurFunction()->ObjCShouldCallSuper) { Diag(MD->getLocEnd(), diag::warn_objc_missing_super_call) << MD->getSelector().getAsString(); getCurFunction()->ObjCShouldCallSuper = false; } } else { return 0; } assert(!getCurFunction()->ObjCShouldCallSuper && "This should only be set for ObjC methods, which should have been " "handled in the block above."); // Verify and clean out per-function state. if (Body) { // C++ constructors that have function-try-blocks can't have return // statements in the handlers of that block. (C++ [except.handle]p14) // Verify this. if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); // Verify that gotos and switch cases don't jump into scopes illegally. if (getCurFunction()->NeedsScopeChecking() && !dcl->isInvalidDecl() && !hasAnyUnrecoverableErrorsInThisFunction() && !PP.isCodeCompletionEnabled()) DiagnoseInvalidJumps(Body); if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { if (!Destructor->getParent()->isDependentType()) CheckDestructor(Destructor); MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), Destructor->getParent()); } // If any errors have occurred, clear out any temporaries that may have // been leftover. This ensures that these temporaries won't be picked up for // deletion in some later function. if (PP.getDiagnostics().hasErrorOccurred() || PP.getDiagnostics().getSuppressAllDiagnostics()) { DiscardCleanupsInEvaluationContext(); } if (!PP.getDiagnostics().hasUncompilableErrorOccurred() && !isa<FunctionTemplateDecl>(dcl)) { // Since the body is valid, issue any analysis-based warnings that are // enabled. ActivePolicy = &WP; } if (!IsInstantiation && FD && FD->isConstexpr() && !FD->isInvalidDecl() && (!CheckConstexprFunctionDecl(FD) || !CheckConstexprFunctionBody(FD, Body))) FD->setInvalidDecl(); assert(ExprCleanupObjects.empty() && "Leftover temporaries in function"); assert(!ExprNeedsCleanups && "Unaccounted cleanups in function"); assert(MaybeODRUseExprs.empty() && "Leftover expressions for odr-use checking"); } if (!IsInstantiation) PopDeclContext(); PopFunctionScopeInfo(ActivePolicy, dcl); // If any errors have occurred, clear out any temporaries that may have // been leftover. This ensures that these temporaries won't be picked up for // deletion in some later function. if (getDiagnostics().hasErrorOccurred()) { DiscardCleanupsInEvaluationContext(); } return dcl; } /// When we finish delayed parsing of an attribute, we must attach it to the /// relevant Decl. void Sema::ActOnFinishDelayedAttribute(Scope *S, Decl *D, ParsedAttributes &Attrs) { // Always attach attributes to the underlying decl. if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D)) D = TD->getTemplatedDecl(); ProcessDeclAttributeList(S, D, Attrs.getList()); if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(D)) if (Method->isStatic()) checkThisInStaticMemberFunctionAttributes(Method); } /// ImplicitlyDefineFunction - An undeclared identifier was used in a function /// call, forming a call to an implicitly defined function (per C99 6.5.1p2). NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, IdentifierInfo &II, Scope *S) { // Before we produce a declaration for an implicitly defined // function, see whether there was a locally-scoped declaration of // this name as a function or variable. If so, use that // (non-visible) declaration, and complain about it. if (NamedDecl *ExternCPrev = findLocallyScopedExternCDecl(&II)) { Diag(Loc, diag::warn_use_out_of_scope_declaration) << ExternCPrev; Diag(ExternCPrev->getLocation(), diag::note_previous_declaration); return ExternCPrev; } // Extension in C99. Legal in C90, but warn about it. unsigned diag_id; if (II.getName().startswith("__builtin_")) diag_id = diag::warn_builtin_unknown; else if (getLangOpts().C99) diag_id = diag::ext_implicit_function_decl; else diag_id = diag::warn_implicit_function_decl; Diag(Loc, diag_id) << &II; // Because typo correction is expensive, only do it if the implicit // function declaration is going to be treated as an error. if (Diags.getDiagnosticLevel(diag_id, Loc) >= DiagnosticsEngine::Error) { TypoCorrection Corrected; DeclFilterCCC<FunctionDecl> Validator; if (S && (Corrected = CorrectTypo(DeclarationNameInfo(&II, Loc), LookupOrdinaryName, S, 0, Validator))) { std::string CorrectedStr = Corrected.getAsString(getLangOpts()); std::string CorrectedQuotedStr = Corrected.getQuoted(getLangOpts()); FunctionDecl *Func = Corrected.getCorrectionDeclAs<FunctionDecl>(); Diag(Loc, diag::note_function_suggestion) << CorrectedQuotedStr << FixItHint::CreateReplacement(Loc, CorrectedStr); if (Func->getLocation().isValid() && !II.getName().startswith("__builtin_")) Diag(Func->getLocation(), diag::note_previous_decl) << CorrectedQuotedStr; } } // Set a Declarator for the implicit definition: int foo(); const char *Dummy; AttributeFactory attrFactory; DeclSpec DS(attrFactory); unsigned DiagID; bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); (void)Error; // Silence warning. assert(!Error && "Error setting up implicit decl!"); SourceLocation NoLoc; Declarator D(DS, Declarator::BlockContext); D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false, /*IsAmbiguous=*/false, /*RParenLoc=*/NoLoc, /*ArgInfo=*/0, /*NumArgs=*/0, /*EllipsisLoc=*/NoLoc, /*RParenLoc=*/NoLoc, /*TypeQuals=*/0, /*RefQualifierIsLvalueRef=*/true, /*RefQualifierLoc=*/NoLoc, /*ConstQualifierLoc=*/NoLoc, /*VolatileQualifierLoc=*/NoLoc, /*MutableLoc=*/NoLoc, EST_None, /*ESpecLoc=*/NoLoc, /*Exceptions=*/0, /*ExceptionRanges=*/0, /*NumExceptions=*/0, /*NoexceptExpr=*/0, Loc, Loc, D), DS.getAttributes(), SourceLocation()); D.SetIdentifier(&II, Loc); // Insert this function into translation-unit scope. DeclContext *PrevDC = CurContext; CurContext = Context.getTranslationUnitDecl(); FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); FD->setImplicit(); CurContext = PrevDC; AddKnownFunctionAttributes(FD); return FD; } /// \brief Adds any function attributes that we know a priori based on /// the declaration of this function. /// /// These attributes can apply both to implicitly-declared builtins /// (like __builtin___printf_chk) or to library-declared functions /// like NSLog or printf. /// /// We need to check for duplicate attributes both here and where user-written /// attributes are applied to declarations. void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { if (FD->isInvalidDecl()) return; // If this is a built-in function, map its builtin attributes to // actual attributes. if (unsigned BuiltinID = FD->getBuiltinID()) { // Handle printf-formatting attributes. unsigned FormatIdx; bool HasVAListArg; if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { if (!FD->getAttr<FormatAttr>()) { const char *fmt = "printf"; unsigned int NumParams = FD->getNumParams(); if (FormatIdx < NumParams && // NumParams may be 0 (e.g. vfprintf) FD->getParamDecl(FormatIdx)->getType()->isObjCObjectPointerType()) fmt = "NSString"; FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, fmt, FormatIdx+1, HasVAListArg ? 0 : FormatIdx+2)); } } if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, HasVAListArg)) { if (!FD->getAttr<FormatAttr>()) FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, "scanf", FormatIdx+1, HasVAListArg ? 0 : FormatIdx+2)); } // Mark const if we don't care about errno and that is the only // thing preventing the function from being const. This allows // IRgen to use LLVM intrinsics for such functions. if (!getLangOpts().MathErrno && Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { if (!FD->getAttr<ConstAttr>()) FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); } if (Context.BuiltinInfo.isReturnsTwice(BuiltinID) && !FD->getAttr<ReturnsTwiceAttr>()) FD->addAttr(::new (Context) ReturnsTwiceAttr(FD->getLocation(), Context)); if (Context.BuiltinInfo.isNoThrow(BuiltinID) && !FD->getAttr<NoThrowAttr>()) FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); if (Context.BuiltinInfo.isConst(BuiltinID) && !FD->getAttr<ConstAttr>()) FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); } IdentifierInfo *Name = FD->getIdentifier(); if (!Name) return; if ((!getLangOpts().CPlusPlus && FD->getDeclContext()->isTranslationUnit()) || (isa<LinkageSpecDecl>(FD->getDeclContext()) && cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == LinkageSpecDecl::lang_c)) { // Okay: this could be a libc/libm/Objective-C function we know // about. } else return; if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { // FIXME: asprintf and vasprintf aren't C99 functions. Should they be // target-specific builtins, perhaps? if (!FD->getAttr<FormatAttr>()) FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, "printf", 2, Name->isStr("vasprintf") ? 0 : 3)); } if (Name->isStr("__CFStringMakeConstantString")) { // We already have a __builtin___CFStringMakeConstantString, // but builds that use -fno-constant-cfstrings don't go through that. if (!FD->getAttr<FormatArgAttr>()) FD->addAttr(::new (Context) FormatArgAttr(FD->getLocation(), Context, 1)); } } TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, TypeSourceInfo *TInfo) { assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); if (!TInfo) { assert(D.isInvalidType() && "no declarator info for valid type"); TInfo = Context.getTrivialTypeSourceInfo(T); } // Scope manipulation handled by caller. TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, D.getLocStart(), D.getIdentifierLoc(), D.getIdentifier(), TInfo); // Bail out immediately if we have an invalid declaration. if (D.isInvalidType()) { NewTD->setInvalidDecl(); return NewTD; } if (D.getDeclSpec().isModulePrivateSpecified()) { if (CurContext->isFunctionOrMethod()) Diag(NewTD->getLocation(), diag::err_module_private_local) << 2 << NewTD->getDeclName() << SourceRange(D.getDeclSpec().getModulePrivateSpecLoc()) << FixItHint::CreateRemoval(D.getDeclSpec().getModulePrivateSpecLoc()); else NewTD->setModulePrivate(); } // C++ [dcl.typedef]p8: // If the typedef declaration defines an unnamed class (or // enum), the first typedef-name declared by the declaration // to be that class type (or enum type) is used to denote the // class type (or enum type) for linkage purposes only. // We need to check whether the type was declared in the declaration. switch (D.getDeclSpec().getTypeSpecType()) { case TST_enum: case TST_struct: case TST_interface: case TST_union: case TST_class: { TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl()); // Do nothing if the tag is not anonymous or already has an // associated typedef (from an earlier typedef in this decl group). if (tagFromDeclSpec->getIdentifier()) break; if (tagFromDeclSpec->getTypedefNameForAnonDecl()) break; // A well-formed anonymous tag must always be a TUK_Definition. assert(tagFromDeclSpec->isThisDeclarationADefinition()); // The type must match the tag exactly; no qualifiers allowed. if (!Context.hasSameType(T, Context.getTagDeclType(tagFromDeclSpec))) break; // Otherwise, set this is the anon-decl typedef for the tag. tagFromDeclSpec->setTypedefNameForAnonDecl(NewTD); break; } default: break; } return NewTD; } /// \brief Check that this is a valid underlying type for an enum declaration. bool Sema::CheckEnumUnderlyingType(TypeSourceInfo *TI) { SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); QualType T = TI->getType(); if (T->isDependentType()) return false; if (const BuiltinType *BT = T->getAs<BuiltinType>()) if (BT->isInteger()) return false; Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) << T; return true; } /// Check whether this is a valid redeclaration of a previous enumeration. /// \return true if the redeclaration was invalid. bool Sema::CheckEnumRedeclaration(SourceLocation EnumLoc, bool IsScoped, QualType EnumUnderlyingTy, const EnumDecl *Prev) { bool IsFixed = !EnumUnderlyingTy.isNull(); if (IsScoped != Prev->isScoped()) { Diag(EnumLoc, diag::err_enum_redeclare_scoped_mismatch) << Prev->isScoped(); Diag(Prev->getLocation(), diag::note_previous_use); return true; } if (IsFixed && Prev->isFixed()) { if (!EnumUnderlyingTy->isDependentType() && !Prev->getIntegerType()->isDependentType() && !Context.hasSameUnqualifiedType(EnumUnderlyingTy, Prev->getIntegerType())) { Diag(EnumLoc, diag::err_enum_redeclare_type_mismatch) << EnumUnderlyingTy << Prev->getIntegerType(); Diag(Prev->getLocation(), diag::note_previous_use); return true; } } else if (IsFixed != Prev->isFixed()) { Diag(EnumLoc, diag::err_enum_redeclare_fixed_mismatch) << Prev->isFixed(); Diag(Prev->getLocation(), diag::note_previous_use); return true; } return false; } /// \brief Get diagnostic %select index for tag kind for /// redeclaration diagnostic message. /// WARNING: Indexes apply to particular diagnostics only! /// /// \returns diagnostic %select index. static unsigned getRedeclDiagFromTagKind(TagTypeKind Tag) { switch (Tag) { case TTK_Struct: return 0; case TTK_Interface: return 1; case TTK_Class: return 2; default: llvm_unreachable("Invalid tag kind for redecl diagnostic!"); } } /// \brief Determine if tag kind is a class-key compatible with /// class for redeclaration (class, struct, or __interface). /// /// \returns true iff the tag kind is compatible. static bool isClassCompatTagKind(TagTypeKind Tag) { return Tag == TTK_Struct || Tag == TTK_Class || Tag == TTK_Interface; } /// \brief Determine whether a tag with a given kind is acceptable /// as a redeclaration of the given tag declaration. /// /// \returns true if the new tag kind is acceptable, false otherwise. bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, TagTypeKind NewTag, bool isDefinition, SourceLocation NewTagLoc, const IdentifierInfo &Name) { // C++ [dcl.type.elab]p3: // The class-key or enum keyword present in the // elaborated-type-specifier shall agree in kind with the // declaration to which the name in the elaborated-type-specifier // refers. This rule also applies to the form of // elaborated-type-specifier that declares a class-name or // friend class since it can be construed as referring to the // definition of the class. Thus, in any // elaborated-type-specifier, the enum keyword shall be used to // refer to an enumeration (7.2), the union class-key shall be // used to refer to a union (clause 9), and either the class or // struct class-key shall be used to refer to a class (clause 9) // declared using the class or struct class-key. TagTypeKind OldTag = Previous->getTagKind(); if (!isDefinition || !isClassCompatTagKind(NewTag)) if (OldTag == NewTag) return true; if (isClassCompatTagKind(OldTag) && isClassCompatTagKind(NewTag)) { // Warn about the struct/class tag mismatch. bool isTemplate = false; if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) isTemplate = Record->getDescribedClassTemplate(); if (!ActiveTemplateInstantiations.empty()) { // In a template instantiation, do not offer fix-its for tag mismatches // since they usually mess up the template instead of fixing the problem. Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) << getRedeclDiagFromTagKind(NewTag) << isTemplate << &Name << getRedeclDiagFromTagKind(OldTag); return true; } if (isDefinition) { // On definitions, check previous tags and issue a fix-it for each // one that doesn't match the current tag. if (Previous->getDefinition()) { // Don't suggest fix-its for redefinitions. return true; } bool previousMismatch = false; for (TagDecl::redecl_iterator I(Previous->redecls_begin()), E(Previous->redecls_end()); I != E; ++I) { if (I->getTagKind() != NewTag) { if (!previousMismatch) { previousMismatch = true; Diag(NewTagLoc, diag::warn_struct_class_previous_tag_mismatch) << getRedeclDiagFromTagKind(NewTag) << isTemplate << &Name << getRedeclDiagFromTagKind(I->getTagKind()); } Diag(I->getInnerLocStart(), diag::note_struct_class_suggestion) << getRedeclDiagFromTagKind(NewTag) << FixItHint::CreateReplacement(I->getInnerLocStart(), TypeWithKeyword::getTagTypeKindName(NewTag)); } } return true; } // Check for a previous definition. If current tag and definition // are same type, do nothing. If no definition, but disagree with // with previous tag type, give a warning, but no fix-it. const TagDecl *Redecl = Previous->getDefinition() ? Previous->getDefinition() : Previous; if (Redecl->getTagKind() == NewTag) { return true; } Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) << getRedeclDiagFromTagKind(NewTag) << isTemplate << &Name << getRedeclDiagFromTagKind(OldTag); Diag(Redecl->getLocation(), diag::note_previous_use); // If there is a previous defintion, suggest a fix-it. if (Previous->getDefinition()) { Diag(NewTagLoc, diag::note_struct_class_suggestion) << getRedeclDiagFromTagKind(Redecl->getTagKind()) << FixItHint::CreateReplacement(SourceRange(NewTagLoc), TypeWithKeyword::getTagTypeKindName(Redecl->getTagKind())); } return true; } return false; } /// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the /// former case, Name will be non-null. In the later case, Name will be null. /// TagSpec indicates what kind of tag this is. TUK indicates whether this is a /// reference/declaration/definition of a tag. Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, SourceLocation KWLoc, CXXScopeSpec &SS, IdentifierInfo *Name, SourceLocation NameLoc, AttributeList *Attr, AccessSpecifier AS, SourceLocation ModulePrivateLoc, MultiTemplateParamsArg TemplateParameterLists, bool &OwnedDecl, bool &IsDependent, SourceLocation ScopedEnumKWLoc, bool ScopedEnumUsesClassTag, TypeResult UnderlyingType) { // If this is not a definition, it must have a name. IdentifierInfo *OrigName = Name; assert((Name != 0 || TUK == TUK_Definition) && "Nameless record must be a definition!"); assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference); OwnedDecl = false; TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); bool ScopedEnum = ScopedEnumKWLoc.isValid(); // FIXME: Check explicit specializations more carefully. bool isExplicitSpecialization = false; bool Invalid = false; // We only need to do this matching if we have template parameters // or a scope specifier, which also conveniently avoids this work // for non-C++ cases. if (TemplateParameterLists.size() > 0 || (SS.isNotEmpty() && TUK != TUK_Reference)) { if (TemplateParameterList *TemplateParams = MatchTemplateParametersToScopeSpecifier( KWLoc, NameLoc, SS, TemplateParameterLists, TUK == TUK_Friend, isExplicitSpecialization, Invalid)) { if (Kind == TTK_Enum) { Diag(KWLoc, diag::err_enum_template); return 0; } if (TemplateParams->size() > 0) { // This is a declaration or definition of a class template (which may // be a member of another template). if (Invalid) return 0; OwnedDecl = false; DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, Name, NameLoc, Attr, TemplateParams, AS, ModulePrivateLoc, TemplateParameterLists.size()-1, TemplateParameterLists.data()); return Result.get(); } else { // The "template<>" header is extraneous. Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) << TypeWithKeyword::getTagTypeKindName(Kind) << Name; isExplicitSpecialization = true; } } } // Figure out the underlying type if this a enum declaration. We need to do // this early, because it's needed to detect if this is an incompatible // redeclaration. llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; if (Kind == TTK_Enum) { if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) // No underlying type explicitly specified, or we failed to parse the // type, default to int. EnumUnderlying = Context.IntTy.getTypePtr(); else if (UnderlyingType.get()) { // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an // integral type; any cv-qualification is ignored. TypeSourceInfo *TI = 0; GetTypeFromParser(UnderlyingType.get(), &TI); EnumUnderlying = TI; if (CheckEnumUnderlyingType(TI)) // Recover by falling back to int. EnumUnderlying = Context.IntTy.getTypePtr(); if (DiagnoseUnexpandedParameterPack(TI->getTypeLoc().getBeginLoc(), TI, UPPC_FixedUnderlyingType)) EnumUnderlying = Context.IntTy.getTypePtr(); } else if (getLangOpts().MicrosoftMode) // Microsoft enums are always of int type. EnumUnderlying = Context.IntTy.getTypePtr(); } DeclContext *SearchDC = CurContext; DeclContext *DC = CurContext; bool isStdBadAlloc = false; RedeclarationKind Redecl = ForRedeclaration; if (TUK == TUK_Friend || TUK == TUK_Reference) Redecl = NotForRedeclaration; LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); bool FriendSawTagOutsideEnclosingNamespace = false; if (Name && SS.isNotEmpty()) { // We have a nested-name tag ('struct foo::bar'). // Check for invalid 'foo::'. if (SS.isInvalid()) { Name = 0; goto CreateNewDecl; } // If this is a friend or a reference to a class in a dependent // context, don't try to make a decl for it. if (TUK == TUK_Friend || TUK == TUK_Reference) { DC = computeDeclContext(SS, false); if (!DC) { IsDependent = true; return 0; } } else { DC = computeDeclContext(SS, true); if (!DC) { Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) << SS.getRange(); return 0; } } if (RequireCompleteDeclContext(SS, DC)) return 0; SearchDC = DC; // Look-up name inside 'foo::'. LookupQualifiedName(Previous, DC); if (Previous.isAmbiguous()) return 0; if (Previous.empty()) { // Name lookup did not find anything. However, if the // nested-name-specifier refers to the current instantiation, // and that current instantiation has any dependent base // classes, we might find something at instantiation time: treat // this as a dependent elaborated-type-specifier. // But this only makes any sense for reference-like lookups. if (Previous.wasNotFoundInCurrentInstantiation() && (TUK == TUK_Reference || TUK == TUK_Friend)) { IsDependent = true; return 0; } // A tag 'foo::bar' must already exist. Diag(NameLoc, diag::err_not_tag_in_scope) << Kind << Name << DC << SS.getRange(); Name = 0; Invalid = true; goto CreateNewDecl; } } else if (Name) { // If this is a named struct, check to see if there was a previous forward // declaration or definition. // FIXME: We're looking into outer scopes here, even when we // shouldn't be. Doing so can result in ambiguities that we // shouldn't be diagnosing. LookupName(Previous, S); // When declaring or defining a tag, ignore ambiguities introduced // by types using'ed into this scope. if (Previous.isAmbiguous() && (TUK == TUK_Definition || TUK == TUK_Declaration)) { LookupResult::Filter F = Previous.makeFilter(); while (F.hasNext()) { NamedDecl *ND = F.next(); if (ND->getDeclContext()->getRedeclContext() != SearchDC) F.erase(); } F.done(); } // C++11 [namespace.memdef]p3: // If the name in a friend declaration is neither qualified nor // a template-id and the declaration is a function or an // elaborated-type-specifier, the lookup to determine whether // the entity has been previously declared shall not consider // any scopes outside the innermost enclosing namespace. // // Does it matter that this should be by scope instead of by // semantic context? if (!Previous.empty() && TUK == TUK_Friend) { DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext(); LookupResult::Filter F = Previous.makeFilter(); while (F.hasNext()) { NamedDecl *ND = F.next(); DeclContext *DC = ND->getDeclContext()->getRedeclContext(); if (DC->isFileContext() && !EnclosingNS->Encloses(ND->getDeclContext())) { F.erase(); FriendSawTagOutsideEnclosingNamespace = true; } } F.done(); } // Note: there used to be some attempt at recovery here. if (Previous.isAmbiguous()) return 0; if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) { // FIXME: This makes sure that we ignore the contexts associated // with C structs, unions, and enums when looking for a matching // tag declaration or definition. See the similar lookup tweak // in Sema::LookupName; is there a better way to deal with this? while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) SearchDC = SearchDC->getParent(); } } else if (S->isFunctionPrototypeScope()) { // If this is an enum declaration in function prototype scope, set its // initial context to the translation unit. // FIXME: [citation needed] SearchDC = Context.getTranslationUnitDecl(); } if (Previous.isSingleResult() && Previous.getFoundDecl()->isTemplateParameter()) { // Maybe we will complain about the shadowed template parameter. DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); // Just pretend that we didn't see the previous declaration. Previous.clear(); } if (getLangOpts().CPlusPlus && Name && DC && StdNamespace && DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { // This is a declaration of or a reference to "std::bad_alloc". isStdBadAlloc = true; if (Previous.empty() && StdBadAlloc) { // std::bad_alloc has been implicitly declared (but made invisible to // name lookup). Fill in this implicit declaration as the previous // declaration, so that the declarations get chained appropriately. Previous.addDecl(getStdBadAlloc()); } } // If we didn't find a previous declaration, and this is a reference // (or friend reference), move to the correct scope. In C++, we // also need to do a redeclaration lookup there, just in case // there's a shadow friend decl. if (Name && Previous.empty() && (TUK == TUK_Reference || TUK == TUK_Friend)) { if (Invalid) goto CreateNewDecl; assert(SS.isEmpty()); if (TUK == TUK_Reference) { // C++ [basic.scope.pdecl]p5: // -- for an elaborated-type-specifier of the form // // class-key identifier // // if the elaborated-type-specifier is used in the // decl-specifier-seq or parameter-declaration-clause of a // function defined in namespace scope, the identifier is // declared as a class-name in the namespace that contains // the declaration; otherwise, except as a friend // declaration, the identifier is declared in the smallest // non-class, non-function-prototype scope that contains the // declaration. // // C99 6.7.2.3p8 has a similar (but not identical!) provision for // C structs and unions. // // It is an error in C++ to declare (rather than define) an enum // type, including via an elaborated type specifier. We'll // diagnose that later; for now, declare the enum in the same // scope as we would have picked for any other tag type. // // GNU C also supports this behavior as part of its incomplete // enum types extension, while GNU C++ does not. // // Find the context where we'll be declaring the tag. // FIXME: We would like to maintain the current DeclContext as the // lexical context, while (!SearchDC->isFileContext() && !SearchDC->isFunctionOrMethod()) SearchDC = SearchDC->getParent(); // Find the scope where we'll be declaring the tag. while (S->isClassScope() || (getLangOpts().CPlusPlus && S->isFunctionPrototypeScope()) || ((S->getFlags() & Scope::DeclScope) == 0) || (S->getEntity() && ((DeclContext *)S->getEntity())->isTransparentContext())) S = S->getParent(); } else { assert(TUK == TUK_Friend); // C++ [namespace.memdef]p3: // If a friend declaration in a non-local class first declares a // class or function, the friend class or function is a member of // the innermost enclosing namespace. SearchDC = SearchDC->getEnclosingNamespaceContext(); } // In C++, we need to do a redeclaration lookup to properly // diagnose some problems. if (getLangOpts().CPlusPlus) { Previous.setRedeclarationKind(ForRedeclaration); LookupQualifiedName(Previous, SearchDC); } } if (!Previous.empty()) { NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); // It's okay to have a tag decl in the same scope as a typedef // which hides a tag decl in the same scope. Finding this // insanity with a redeclaration lookup can only actually happen // in C++. // // This is also okay for elaborated-type-specifiers, which is // technically forbidden by the current standard but which is // okay according to the likely resolution of an open issue; // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 if (getLangOpts().CPlusPlus) { if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) { if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { TagDecl *Tag = TT->getDecl(); if (Tag->getDeclName() == Name && Tag->getDeclContext()->getRedeclContext() ->Equals(TD->getDeclContext()->getRedeclContext())) { PrevDecl = Tag; Previous.clear(); Previous.addDecl(Tag); Previous.resolveKind(); } } } } if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { // If this is a use of a previous tag, or if the tag is already declared // in the same scope (so that the definition/declaration completes or // rementions the tag), reuse the decl. if (TUK == TUK_Reference || TUK == TUK_Friend || isDeclInScope(PrevDecl, SearchDC, S, isExplicitSpecialization)) { // Make sure that this wasn't declared as an enum and now used as a // struct or something similar. if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, TUK == TUK_Definition, KWLoc, *Name)) { bool SafeToContinue = (PrevTagDecl->getTagKind() != TTK_Enum && Kind != TTK_Enum); if (SafeToContinue) Diag(KWLoc, diag::err_use_with_wrong_tag) << Name << FixItHint::CreateReplacement(SourceRange(KWLoc), PrevTagDecl->getKindName()); else Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; Diag(PrevTagDecl->getLocation(), diag::note_previous_use); if (SafeToContinue) Kind = PrevTagDecl->getTagKind(); else { // Recover by making this an anonymous redefinition. Name = 0; Previous.clear(); Invalid = true; } } if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); // If this is an elaborated-type-specifier for a scoped enumeration, // the 'class' keyword is not necessary and not permitted. if (TUK == TUK_Reference || TUK == TUK_Friend) { if (ScopedEnum) Diag(ScopedEnumKWLoc, diag::err_enum_class_reference) << PrevEnum->isScoped() << FixItHint::CreateRemoval(ScopedEnumKWLoc); return PrevTagDecl; } QualType EnumUnderlyingTy; if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) EnumUnderlyingTy = TI->getType(); else if (const Type *T = EnumUnderlying.dyn_cast<const Type*>()) EnumUnderlyingTy = QualType(T, 0); // All conflicts with previous declarations are recovered by // returning the previous declaration, unless this is a definition, // in which case we want the caller to bail out. if (CheckEnumRedeclaration(NameLoc.isValid() ? NameLoc : KWLoc, ScopedEnum, EnumUnderlyingTy, PrevEnum)) return TUK == TUK_Declaration ? PrevTagDecl : 0; } // C++11 [class.mem]p1: // A member shall not be declared twice in the member-specification, // except that a nested class or member class template can be declared // and then later defined. if (TUK == TUK_Declaration && PrevDecl->isCXXClassMember() && S->isDeclScope(PrevDecl)) { Diag(NameLoc, diag::ext_member_redeclared); Diag(PrevTagDecl->getLocation(), diag::note_previous_declaration); } if (!Invalid) { // If this is a use, just return the declaration we found. // FIXME: In the future, return a variant or some other clue // for the consumer of this Decl to know it doesn't own it. // For our current ASTs this shouldn't be a problem, but will // need to be changed with DeclGroups. if ((TUK == TUK_Reference && (!PrevTagDecl->getFriendObjectKind() || getLangOpts().MicrosoftExt)) || TUK == TUK_Friend) return PrevTagDecl; // Diagnose attempts to redefine a tag. if (TUK == TUK_Definition) { if (TagDecl *Def = PrevTagDecl->getDefinition()) { // If we're defining a specialization and the previous definition // is from an implicit instantiation, don't emit an error // here; we'll catch this in the general case below. bool IsExplicitSpecializationAfterInstantiation = false; if (isExplicitSpecialization) { if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Def)) IsExplicitSpecializationAfterInstantiation = RD->getTemplateSpecializationKind() != TSK_ExplicitSpecialization; else if (EnumDecl *ED = dyn_cast<EnumDecl>(Def)) IsExplicitSpecializationAfterInstantiation = ED->getTemplateSpecializationKind() != TSK_ExplicitSpecialization; } if (!IsExplicitSpecializationAfterInstantiation) { // A redeclaration in function prototype scope in C isn't // visible elsewhere, so merely issue a warning. if (!getLangOpts().CPlusPlus && S->containedInPrototypeScope()) Diag(NameLoc, diag::warn_redefinition_in_param_list) << Name; else Diag(NameLoc, diag::err_redefinition) << Name; Diag(Def->getLocation(), diag::note_previous_definition); // If this is a redefinition, recover by making this // struct be anonymous, which will make any later // references get the previous definition. Name = 0; Previous.clear(); Invalid = true; } } else { // If the type is currently being defined, complain // about a nested redefinition. const TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); if (Tag->isBeingDefined()) { Diag(NameLoc, diag::err_nested_redefinition) << Name; Diag(PrevTagDecl->getLocation(), diag::note_previous_definition); Name = 0; Previous.clear(); Invalid = true; } } // Okay, this is definition of a previously declared or referenced // tag PrevDecl. We're going to create a new Decl for it. } } // If we get here we have (another) forward declaration or we // have a definition. Just create a new decl. } else { // If we get here, this is a definition of a new tag type in a nested // scope, e.g. "struct foo; void bar() { struct foo; }", just create a // new decl/type. We set PrevDecl to NULL so that the entities // have distinct types. Previous.clear(); } // If we get here, we're going to create a new Decl. If PrevDecl // is non-NULL, it's a definition of the tag declared by // PrevDecl. If it's NULL, we have a new definition. // Otherwise, PrevDecl is not a tag, but was found with tag // lookup. This is only actually possible in C++, where a few // things like templates still live in the tag namespace. } else { // Use a better diagnostic if an elaborated-type-specifier // found the wrong kind of type on the first // (non-redeclaration) lookup. if ((TUK == TUK_Reference || TUK == TUK_Friend) && !Previous.isForRedeclaration()) { unsigned Kind = 0; if (isa<TypedefDecl>(PrevDecl)) Kind = 1; else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2; else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3; Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; Diag(PrevDecl->getLocation(), diag::note_declared_at); Invalid = true; // Otherwise, only diagnose if the declaration is in scope. } else if (!isDeclInScope(PrevDecl, SearchDC, S, isExplicitSpecialization)) { // do nothing // Diagnose implicit declarations introduced by elaborated types. } else if (TUK == TUK_Reference || TUK == TUK_Friend) { unsigned Kind = 0; if (isa<TypedefDecl>(PrevDecl)) Kind = 1; else if (isa<TypeAliasDecl>(PrevDecl)) Kind = 2; else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 3; Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; Invalid = true; // Otherwise it's a declaration. Call out a particularly common // case here. } else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) { unsigned Kind = 0; if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1; Diag(NameLoc, diag::err_tag_definition_of_typedef) << Name << Kind << TND->getUnderlyingType(); Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; Invalid = true; // Otherwise, diagnose. } else { // The tag name clashes with something else in the target scope, // issue an error and recover by making this tag be anonymous. Diag(NameLoc, diag::err_redefinition_different_kind) << Name; Diag(PrevDecl->getLocation(), diag::note_previous_definition); Name = 0; Invalid = true; } // The existing declaration isn't relevant to us; we're in a // new scope, so clear out the previous declaration. Previous.clear(); } } CreateNewDecl: TagDecl *PrevDecl = 0; if (Previous.isSingleResult()) PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); // If there is an identifier, use the location of the identifier as the // location of the decl, otherwise use the location of the struct/union // keyword. SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; // Otherwise, create a new declaration. If there is a previous // declaration of the same entity, the two will be linked via // PrevDecl. TagDecl *New; bool IsForwardReference = false; if (Kind == TTK_Enum) { // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: // enum X { A, B, C } D; D should chain to X. New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name, cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, ScopedEnumUsesClassTag, !EnumUnderlying.isNull()); // If this is an undefined enum, warn. if (TUK != TUK_Definition && !Invalid) { TagDecl *Def; if ((getLangOpts().CPlusPlus11 || getLangOpts().ObjC2) && cast<EnumDecl>(New)->isFixed()) { // C++0x: 7.2p2: opaque-enum-declaration. // Conflicts are diagnosed above. Do nothing. } else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { Diag(Loc, diag::ext_forward_ref_enum_def) << New; Diag(Def->getLocation(), diag::note_previous_definition); } else { unsigned DiagID = diag::ext_forward_ref_enum; if (getLangOpts().MicrosoftMode) DiagID = diag::ext_ms_forward_ref_enum; else if (getLangOpts().CPlusPlus) DiagID = diag::err_forward_ref_enum; Diag(Loc, DiagID); // If this is a forward-declared reference to an enumeration, make a // note of it; we won't actually be introducing the declaration into // the declaration context. if (TUK == TUK_Reference) IsForwardReference = true; } } if (EnumUnderlying) { EnumDecl *ED = cast<EnumDecl>(New); if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) ED->setIntegerTypeSourceInfo(TI); else ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); ED->setPromotionType(ED->getIntegerType()); } } else { // struct/union/class // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: // struct X { int A; } D; D should chain to X. if (getLangOpts().CPlusPlus) { // FIXME: Look for a way to use RecordDecl for simple structs. New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, cast_or_null<CXXRecordDecl>(PrevDecl)); if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) StdBadAlloc = cast<CXXRecordDecl>(New); } else New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, cast_or_null<RecordDecl>(PrevDecl)); } // Maybe add qualifier info. if (SS.isNotEmpty()) { if (SS.isSet()) { // If this is either a declaration or a definition, check the // nested-name-specifier against the current context. We don't do this // for explicit specializations, because they have similar checking // (with more specific diagnostics) in the call to // CheckMemberSpecialization, below. if (!isExplicitSpecialization && (TUK == TUK_Definition || TUK == TUK_Declaration) && diagnoseQualifiedDeclaration(SS, DC, OrigName, NameLoc)) Invalid = true; New->setQualifierInfo(SS.getWithLocInContext(Context)); if (TemplateParameterLists.size() > 0) { New->setTemplateParameterListsInfo(Context, TemplateParameterLists.size(), TemplateParameterLists.data()); } } else Invalid = true; } if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { // Add alignment attributes if necessary; these attributes are checked when // the ASTContext lays out the structure. // // It is important for implementing the correct semantics that this // happen here (in act on tag decl). The #pragma pack stack is // maintained as a result of parser callbacks which can occur at // many points during the parsing of a struct declaration (because // the #pragma tokens are effectively skipped over during the // parsing of the struct). if (TUK == TUK_Definition) { AddAlignmentAttributesForRecord(RD); AddMsStructLayoutForRecord(RD); } } if (ModulePrivateLoc.isValid()) { if (isExplicitSpecialization) Diag(New->getLocation(), diag::err_module_private_specialization) << 2 << FixItHint::CreateRemoval(ModulePrivateLoc); // __module_private__ does not apply to local classes. However, we only // diagnose this as an error when the declaration specifiers are // freestanding. Here, we just ignore the __module_private__. else if (!SearchDC->isFunctionOrMethod()) New->setModulePrivate(); } // If this is a specialization of a member class (of a class template), // check the specialization. if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) Invalid = true; if (Invalid) New->setInvalidDecl(); if (Attr) ProcessDeclAttributeList(S, New, Attr); // If we're declaring or defining a tag in function prototype scope // in C, note that this type can only be used within the function. if (Name && S->isFunctionPrototypeScope() && !getLangOpts().CPlusPlus) Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); // Set the lexical context. If the tag has a C++ scope specifier, the // lexical context will be different from the semantic context. New->setLexicalDeclContext(CurContext); // Mark this as a friend decl if applicable. // In Microsoft mode, a friend declaration also acts as a forward // declaration so we always pass true to setObjectOfFriendDecl to make // the tag name visible. if (TUK == TUK_Friend) New->setObjectOfFriendDecl(!FriendSawTagOutsideEnclosingNamespace && getLangOpts().MicrosoftExt); // Set the access specifier. if (!Invalid && SearchDC->isRecord()) SetMemberAccessSpecifier(New, PrevDecl, AS); if (TUK == TUK_Definition) New->startDefinition(); // If this has an identifier, add it to the scope stack. if (TUK == TUK_Friend) { // We might be replacing an existing declaration in the lookup tables; // if so, borrow its access specifier. if (PrevDecl) New->setAccess(PrevDecl->getAccess()); DeclContext *DC = New->getDeclContext()->getRedeclContext(); DC->makeDeclVisibleInContext(New); if (Name) // can be null along some error paths if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); } else if (Name) { S = getNonFieldDeclScope(S); PushOnScopeChains(New, S, !IsForwardReference); if (IsForwardReference) SearchDC->makeDeclVisibleInContext(New); } else { CurContext->addDecl(New); } // If this is the C FILE type, notify the AST context. if (IdentifierInfo *II = New->getIdentifier()) if (!New->isInvalidDecl() && New->getDeclContext()->getRedeclContext()->isTranslationUnit() && II->isStr("FILE")) Context.setFILEDecl(New); // If we were in function prototype scope (and not in C++ mode), add this // tag to the list of decls to inject into the function definition scope. if (S->isFunctionPrototypeScope() && !getLangOpts().CPlusPlus && InFunctionDeclarator && Name) DeclsInPrototypeScope.push_back(New); if (PrevDecl) mergeDeclAttributes(New, PrevDecl); // If there's a #pragma GCC visibility in scope, set the visibility of this // record. AddPushedVisibilityAttribute(New); OwnedDecl = true; // In C++, don't return an invalid declaration. We can't recover well from // the cases where we make the type anonymous. return (Invalid && getLangOpts().CPlusPlus) ? 0 : New; } void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { AdjustDeclIfTemplate(TagD); TagDecl *Tag = cast<TagDecl>(TagD); // Enter the tag context. PushDeclContext(S, Tag); ActOnDocumentableDecl(TagD); // If there's a #pragma GCC visibility in scope, set the visibility of this // record. AddPushedVisibilityAttribute(Tag); } Decl *Sema::ActOnObjCContainerStartDefinition(Decl *IDecl) { assert(isa<ObjCContainerDecl>(IDecl) && "ActOnObjCContainerStartDefinition - Not ObjCContainerDecl"); DeclContext *OCD = cast<DeclContext>(IDecl); assert(getContainingDC(OCD) == CurContext && "The next DeclContext should be lexically contained in the current one."); CurContext = OCD; return IDecl; } void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, SourceLocation FinalLoc, SourceLocation LBraceLoc) { AdjustDeclIfTemplate(TagD); CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); FieldCollector->StartClass(); if (!Record->getIdentifier()) return; if (FinalLoc.isValid()) Record->addAttr(new (Context) FinalAttr(FinalLoc, Context)); // C++ [class]p2: // [...] The class-name is also inserted into the scope of the // class itself; this is known as the injected-class-name. For // purposes of access checking, the injected-class-name is treated // as if it were a public member name. CXXRecordDecl *InjectedClassName = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext, Record->getLocStart(), Record->getLocation(), Record->getIdentifier(), /*PrevDecl=*/0, /*DelayTypeCreation=*/true); Context.getTypeDeclType(InjectedClassName, Record); InjectedClassName->setImplicit(); InjectedClassName->setAccess(AS_public); if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) InjectedClassName->setDescribedClassTemplate(Template); PushOnScopeChains(InjectedClassName, S); assert(InjectedClassName->isInjectedClassName() && "Broken injected-class-name"); } void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, SourceLocation RBraceLoc) { AdjustDeclIfTemplate(TagD); TagDecl *Tag = cast<TagDecl>(TagD); Tag->setRBraceLoc(RBraceLoc); // Make sure we "complete" the definition even it is invalid. if (Tag->isBeingDefined()) { assert(Tag->isInvalidDecl() && "We should already have completed it"); if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag)) RD->completeDefinition(); } if (isa<CXXRecordDecl>(Tag)) FieldCollector->FinishClass(); // Exit this scope of this tag's definition. PopDeclContext(); if (getCurLexicalContext()->isObjCContainer() && Tag->getDeclContext()->isFileContext()) Tag->setTopLevelDeclInObjCContainer(); // Notify the consumer that we've defined a tag. if (!Tag->isInvalidDecl()) Consumer.HandleTagDeclDefinition(Tag); } void Sema::ActOnObjCContainerFinishDefinition() { // Exit this scope of this interface definition. PopDeclContext(); } void Sema::ActOnObjCTemporaryExitContainerContext(DeclContext *DC) { assert(DC == CurContext && "Mismatch of container contexts"); OriginalLexicalContext = DC; ActOnObjCContainerFinishDefinition(); } void Sema::ActOnObjCReenterContainerContext(DeclContext *DC) { ActOnObjCContainerStartDefinition(cast<Decl>(DC)); OriginalLexicalContext = 0; } void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { AdjustDeclIfTemplate(TagD); TagDecl *Tag = cast<TagDecl>(TagD); Tag->setInvalidDecl(); // Make sure we "complete" the definition even it is invalid. if (Tag->isBeingDefined()) { if (RecordDecl *RD = dyn_cast<RecordDecl>(Tag)) RD->completeDefinition(); } // We're undoing ActOnTagStartDefinition here, not // ActOnStartCXXMemberDeclarations, so we don't have to mess with // the FieldCollector. PopDeclContext(); } // Note that FieldName may be null for anonymous bitfields. ExprResult Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, QualType FieldTy, bool IsMsStruct, Expr *BitWidth, bool *ZeroWidth) { // Default to true; that shouldn't confuse checks for emptiness if (ZeroWidth) *ZeroWidth = true; // C99 6.7.2.1p4 - verify the field type. // C++ 9.6p3: A bit-field shall have integral or enumeration type. if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { // Handle incomplete types with specific error. if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) return ExprError(); if (FieldName) return Diag(FieldLoc, diag::err_not_integral_type_bitfield) << FieldName << FieldTy << BitWidth->getSourceRange(); return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) << FieldTy << BitWidth->getSourceRange(); } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth), UPPC_BitFieldWidth)) return ExprError(); // If the bit-width is type- or value-dependent, don't try to check // it now. if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) return Owned(BitWidth); llvm::APSInt Value; ExprResult ICE = VerifyIntegerConstantExpression(BitWidth, &Value); if (ICE.isInvalid()) return ICE; BitWidth = ICE.take(); if (Value != 0 && ZeroWidth) *ZeroWidth = false; // Zero-width bitfield is ok for anonymous field. if (Value == 0 && FieldName) return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; if (Value.isSigned() && Value.isNegative()) { if (FieldName) return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName << Value.toString(10); return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) << Value.toString(10); } if (!FieldTy->isDependentType()) { uint64_t TypeSize = Context.getTypeSize(FieldTy); if (Value.getZExtValue() > TypeSize) { if (!getLangOpts().CPlusPlus || IsMsStruct) { if (FieldName) return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) << FieldName << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; } if (FieldName) Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) << FieldName << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; else Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; } } return Owned(BitWidth); } /// ActOnField - Each field of a C struct/union is passed into this in order /// to create a FieldDecl object for it. Decl *Sema::ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart, Declarator &D, Expr *BitfieldWidth) { FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), DeclStart, D, static_cast<Expr*>(BitfieldWidth), /*InitStyle=*/ICIS_NoInit, AS_public); return Res; } /// HandleField - Analyze a field of a C struct or a C++ data member. /// FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, SourceLocation DeclStart, Declarator &D, Expr *BitWidth, InClassInitStyle InitStyle, AccessSpecifier AS) { IdentifierInfo *II = D.getIdentifier(); SourceLocation Loc = DeclStart; if (II) Loc = D.getIdentifierLoc(); TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); QualType T = TInfo->getType(); if (getLangOpts().CPlusPlus) { CheckExtraCXXDefaultArguments(D); if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, UPPC_DataMemberType)) { D.setInvalidType(); T = Context.IntTy; TInfo = Context.getTrivialTypeSourceInfo(T, Loc); } } // TR 18037 does not allow fields to be declared with address spaces. if (T.getQualifiers().hasAddressSpace()) { Diag(Loc, diag::err_field_with_address_space); D.setInvalidType(); } // OpenCL 1.2 spec, s6.9 r: // The event type cannot be used to declare a structure or union field. if (LangOpts.OpenCL && T->isEventT()) { Diag(Loc, diag::err_event_t_struct_field); D.setInvalidType(); } DiagnoseFunctionSpecifiers(D.getDeclSpec()); if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec()) Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(), diag::err_invalid_thread) << DeclSpec::getSpecifierName(TSCS); // Check to see if this name was declared as a member previously NamedDecl *PrevDecl = 0; LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); LookupName(Previous, S); switch (Previous.getResultKind()) { case LookupResult::Found: case LookupResult::FoundUnresolvedValue: PrevDecl = Previous.getAsSingle<NamedDecl>(); break; case LookupResult::FoundOverloaded: PrevDecl = Previous.getRepresentativeDecl(); break; case LookupResult::NotFound: case LookupResult::NotFoundInCurrentInstantiation: case LookupResult::Ambiguous: break; } Previous.suppressDiagnostics(); if (PrevDecl && PrevDecl->isTemplateParameter()) { // Maybe we will complain about the shadowed template parameter. DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); // Just pretend that we didn't see the previous declaration. PrevDecl = 0; } if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) PrevDecl = 0; bool Mutable = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); SourceLocation TSSL = D.getLocStart(); FieldDecl *NewFD = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, InitStyle, TSSL, AS, PrevDecl, &D); if (NewFD->isInvalidDecl()) Record->setInvalidDecl(); if (D.getDeclSpec().isModulePrivateSpecified()) NewFD->setModulePrivate(); if (NewFD->isInvalidDecl() && PrevDecl) { // Don't introduce NewFD into scope; there's already something // with the same name in the same scope. } else if (II) { PushOnScopeChains(NewFD, S); } else Record->addDecl(NewFD); return NewFD; } /// \brief Build a new FieldDecl and check its well-formedness. /// /// This routine builds a new FieldDecl given the fields name, type, /// record, etc. \p PrevDecl should refer to any previous declaration /// with the same name and in the same scope as the field to be /// created. /// /// \returns a new FieldDecl. /// /// \todo The Declarator argument is a hack. It will be removed once FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, TypeSourceInfo *TInfo, RecordDecl *Record, SourceLocation Loc, bool Mutable, Expr *BitWidth, InClassInitStyle InitStyle, SourceLocation TSSL, AccessSpecifier AS, NamedDecl *PrevDecl, Declarator *D) { IdentifierInfo *II = Name.getAsIdentifierInfo(); bool InvalidDecl = false; if (D) InvalidDecl = D->isInvalidType(); // If we receive a broken type, recover by assuming 'int' and // marking this declaration as invalid. if (T.isNull()) { InvalidDecl = true; T = Context.IntTy; } QualType EltTy = Context.getBaseElementType(T); if (!EltTy->isDependentType()) { if (RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { // Fields of incomplete type force their record to be invalid. Record->setInvalidDecl(); InvalidDecl = true; } else { NamedDecl *Def; EltTy->isIncompleteType(&Def); if (Def && Def->isInvalidDecl()) { Record->setInvalidDecl(); InvalidDecl = true; } } } // OpenCL v1.2 s6.9.c: bitfields are not supported. if (BitWidth && getLangOpts().OpenCL) { Diag(Loc, diag::err_opencl_bitfields); InvalidDecl = true; } // C99 6.7.2.1p8: A member of a structure or union may have any type other // than a variably modified type. if (!InvalidDecl && T->isVariablyModifiedType()) { bool SizeIsNegative; llvm::APSInt Oversized; TypeSourceInfo *FixedTInfo = TryToFixInvalidVariablyModifiedTypeSourceInfo(TInfo, Context, SizeIsNegative, Oversized); if (FixedTInfo) { Diag(Loc, diag::warn_illegal_constant_array_size); TInfo = FixedTInfo; T = FixedTInfo->getType(); } else { if (SizeIsNegative) Diag(Loc, diag::err_typecheck_negative_array_size); else if (Oversized.getBoolValue()) Diag(Loc, diag::err_array_too_large) << Oversized.toString(10); else Diag(Loc, diag::err_typecheck_field_variable_size); InvalidDecl = true; } } // Fields can not have abstract class types if (!InvalidDecl && RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, AbstractFieldType)) InvalidDecl = true; bool ZeroWidth = false; // If this is declared as a bit-field, check the bit-field. if (!InvalidDecl && BitWidth) { BitWidth = VerifyBitField(Loc, II, T, Record->isMsStruct(Context), BitWidth, &ZeroWidth).take(); if (!BitWidth) { InvalidDecl = true; BitWidth = 0; ZeroWidth = false; } } // Check that 'mutable' is consistent with the type of the declaration. if (!InvalidDecl && Mutable) { unsigned DiagID = 0; if (T->isReferenceType()) DiagID = diag::err_mutable_reference; else if (T.isConstQualified()) DiagID = diag::err_mutable_const; if (DiagID) { SourceLocation ErrLoc = Loc; if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); Diag(ErrLoc, DiagID); Mutable = false; InvalidDecl = true; } } FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo, BitWidth, Mutable, InitStyle); if (InvalidDecl) NewFD->setInvalidDecl(); if (PrevDecl && !isa<TagDecl>(PrevDecl)) { Diag(Loc, diag::err_duplicate_member) << II; Diag(PrevDecl->getLocation(), diag::note_previous_declaration); NewFD->setInvalidDecl(); } if (!InvalidDecl && getLangOpts().CPlusPlus) { if (Record->isUnion()) { if (const RecordType *RT = EltTy->getAs<RecordType>()) { CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); if (RDecl->getDefinition()) { // C++ [class.union]p1: An object of a class with a non-trivial // constructor, a non-trivial copy constructor, a non-trivial // destructor, or a non-trivial copy assignment operator // cannot be a member of a union, nor can an array of such // objects. if (CheckNontrivialField(NewFD)) NewFD->setInvalidDecl(); } } // C++ [class.union]p1: If a union contains a member of reference type, // the program is ill-formed, except when compiling with MSVC extensions // enabled. if (EltTy->isReferenceType()) { Diag(NewFD->getLocation(), getLangOpts().MicrosoftExt ? diag::ext_union_member_of_reference_type : diag::err_union_member_of_reference_type) << NewFD->getDeclName() << EltTy; if (!getLangOpts().MicrosoftExt) NewFD->setInvalidDecl(); } } } // FIXME: We need to pass in the attributes given an AST // representation, not a parser representation. if (D) { // FIXME: The current scope is almost... but not entirely... correct here. ProcessDeclAttributes(getCurScope(), NewFD, *D); if (NewFD->hasAttrs()) CheckAlignasUnderalignment(NewFD); } // In auto-retain/release, infer strong retension for fields of // retainable type. if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewFD)) NewFD->setInvalidDecl(); if (T.isObjCGCWeak()) Diag(Loc, diag::warn_attribute_weak_on_field); NewFD->setAccess(AS); return NewFD; } bool Sema::CheckNontrivialField(FieldDecl *FD) { assert(FD); assert(getLangOpts().CPlusPlus && "valid check only for C++"); if (FD->isInvalidDecl() || FD->getType()->isDependentType()) return false; QualType EltTy = Context.getBaseElementType(FD->getType()); if (const RecordType *RT = EltTy->getAs<RecordType>()) { CXXRecordDecl *RDecl = cast<CXXRecordDecl>(RT->getDecl()); if (RDecl->getDefinition()) { // We check for copy constructors before constructors // because otherwise we'll never get complaints about // copy constructors. CXXSpecialMember member = CXXInvalid; // We're required to check for any non-trivial constructors. Since the // implicit default constructor is suppressed if there are any // user-declared constructors, we just need to check that there is a // trivial default constructor and a trivial copy constructor. (We don't // worry about move constructors here, since this is a C++98 check.) if (RDecl->hasNonTrivialCopyConstructor()) member = CXXCopyConstructor; else if (!RDecl->hasTrivialDefaultConstructor()) member = CXXDefaultConstructor; else if (RDecl->hasNonTrivialCopyAssignment()) member = CXXCopyAssignment; else if (RDecl->hasNonTrivialDestructor()) member = CXXDestructor; if (member != CXXInvalid) { if (!getLangOpts().CPlusPlus11 && getLangOpts().ObjCAutoRefCount && RDecl->hasObjectMember()) { // Objective-C++ ARC: it is an error to have a non-trivial field of // a union. However, system headers in Objective-C programs // occasionally have Objective-C lifetime objects within unions, // and rather than cause the program to fail, we make those // members unavailable. SourceLocation Loc = FD->getLocation(); if (getSourceManager().isInSystemHeader(Loc)) { if (!FD->hasAttr<UnavailableAttr>()) FD->addAttr(new (Context) UnavailableAttr(Loc, Context, "this system field has retaining ownership")); return false; } } Diag(FD->getLocation(), getLangOpts().CPlusPlus11 ? diag::warn_cxx98_compat_nontrivial_union_or_anon_struct_member : diag::err_illegal_union_or_anon_struct_member) << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; DiagnoseNontrivial(RDecl, member); return !getLangOpts().CPlusPlus11; } } } return false; } /// TranslateIvarVisibility - Translate visibility from a token ID to an /// AST enum value. static ObjCIvarDecl::AccessControl TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { switch (ivarVisibility) { default: llvm_unreachable("Unknown visitibility kind"); case tok::objc_private: return ObjCIvarDecl::Private; case tok::objc_public: return ObjCIvarDecl::Public; case tok::objc_protected: return ObjCIvarDecl::Protected; case tok::objc_package: return ObjCIvarDecl::Package; } } /// ActOnIvar - Each ivar field of an objective-c class is passed into this /// in order to create an IvarDecl object for it. Decl *Sema::ActOnIvar(Scope *S, SourceLocation DeclStart, Declarator &D, Expr *BitfieldWidth, tok::ObjCKeywordKind Visibility) { IdentifierInfo *II = D.getIdentifier(); Expr *BitWidth = (Expr*)BitfieldWidth; SourceLocation Loc = DeclStart; if (II) Loc = D.getIdentifierLoc(); // FIXME: Unnamed fields can be handled in various different ways, for // example, unnamed unions inject all members into the struct namespace! TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); QualType T = TInfo->getType(); if (BitWidth) { // 6.7.2.1p3, 6.7.2.1p4 BitWidth = VerifyBitField(Loc, II, T, /*IsMsStruct=*/false, BitWidth).take(); if (!BitWidth) D.setInvalidType(); } else { // Not a bitfield. // validate II. } if (T->isReferenceType()) { Diag(Loc, diag::err_ivar_reference_type); D.setInvalidType(); } // C99 6.7.2.1p8: A member of a structure or union may have any type other // than a variably modified type. else if (T->isVariablyModifiedType()) { Diag(Loc, diag::err_typecheck_ivar_variable_size); D.setInvalidType(); } // Get the visibility (access control) for this ivar. ObjCIvarDecl::AccessControl ac = Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) : ObjCIvarDecl::None; // Must set ivar's DeclContext to its enclosing interface. ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(CurContext); if (!EnclosingDecl || EnclosingDecl->isInvalidDecl()) return 0; ObjCContainerDecl *EnclosingContext; if (ObjCImplementationDecl *IMPDecl = dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { if (LangOpts.ObjCRuntime.isFragile()) { // Case of ivar declared in an implementation. Context is that of its class. EnclosingContext = IMPDecl->getClassInterface(); assert(EnclosingContext && "Implementation has no class interface!"); } else EnclosingContext = EnclosingDecl; } else { if (ObjCCategoryDecl *CDecl = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { if (LangOpts.ObjCRuntime.isFragile() || !CDecl->IsClassExtension()) { Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); return 0; } } EnclosingContext = EnclosingDecl; } // Construct the decl. ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext, DeclStart, Loc, II, T, TInfo, ac, (Expr *)BitfieldWidth); if (II) { NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, ForRedeclaration); if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) && !isa<TagDecl>(PrevDecl)) { Diag(Loc, diag::err_duplicate_member) << II; Diag(PrevDecl->getLocation(), diag::note_previous_declaration); NewID->setInvalidDecl(); } } // Process attributes attached to the ivar. ProcessDeclAttributes(S, NewID, D); if (D.isInvalidType()) NewID->setInvalidDecl(); // In ARC, infer 'retaining' for ivars of retainable type. if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(NewID)) NewID->setInvalidDecl(); if (D.getDeclSpec().isModulePrivateSpecified()) NewID->setModulePrivate(); if (II) { // FIXME: When interfaces are DeclContexts, we'll need to add // these to the interface. S->AddDecl(NewID); IdResolver.AddDecl(NewID); } if (LangOpts.ObjCRuntime.isNonFragile() && !NewID->isInvalidDecl() && isa<ObjCInterfaceDecl>(EnclosingDecl)) Diag(Loc, diag::warn_ivars_in_interface); return NewID; } /// ActOnLastBitfield - This routine handles synthesized bitfields rules for /// class and class extensions. For every class \@interface and class /// extension \@interface, if the last ivar is a bitfield of any type, /// then add an implicit `char :0` ivar to the end of that interface. void Sema::ActOnLastBitfield(SourceLocation DeclLoc, SmallVectorImpl<Decl *> &AllIvarDecls) { if (LangOpts.ObjCRuntime.isFragile() || AllIvarDecls.empty()) return; Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); if (!Ivar->isBitField() || Ivar->getBitWidthValue(Context) == 0) return; ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CurContext); if (!ID) { if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(CurContext)) { if (!CD->IsClassExtension()) return; } // No need to add this to end of @implementation. else return; } // All conditions are met. Add a new bitfield to the tail end of ivars. llvm::APInt Zero(Context.getTypeSize(Context.IntTy), 0); Expr * BW = IntegerLiteral::Create(Context, Zero, Context.IntTy, DeclLoc); Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(CurContext), DeclLoc, DeclLoc, 0, Context.CharTy, Context.getTrivialTypeSourceInfo(Context.CharTy, DeclLoc), ObjCIvarDecl::Private, BW, true); AllIvarDecls.push_back(Ivar); } void Sema::ActOnFields(Scope* S, SourceLocation RecLoc, Decl *EnclosingDecl, llvm::ArrayRef<Decl *> Fields, SourceLocation LBrac, SourceLocation RBrac, AttributeList *Attr) { assert(EnclosingDecl && "missing record or interface decl"); // If this is an Objective-C @implementation or category and we have // new fields here we should reset the layout of the interface since // it will now change. if (!Fields.empty() && isa<ObjCContainerDecl>(EnclosingDecl)) { ObjCContainerDecl *DC = cast<ObjCContainerDecl>(EnclosingDecl); switch (DC->getKind()) { default: break; case Decl::ObjCCategory: Context.ResetObjCLayout(cast<ObjCCategoryDecl>(DC)->getClassInterface()); break; case Decl::ObjCImplementation: Context. ResetObjCLayout(cast<ObjCImplementationDecl>(DC)->getClassInterface()); break; } } RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); // Start counting up the number of named members; make sure to include // members of anonymous structs and unions in the total. unsigned NumNamedMembers = 0; if (Record) { for (RecordDecl::decl_iterator i = Record->decls_begin(), e = Record->decls_end(); i != e; i++) { if (IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(*i)) if (IFD->getDeclName()) ++NumNamedMembers; } } // Verify that all the fields are okay. SmallVector<FieldDecl*, 32> RecFields; bool ARCErrReported = false; for (llvm::ArrayRef<Decl *>::iterator i = Fields.begin(), end = Fields.end(); i != end; ++i) { FieldDecl *FD = cast<FieldDecl>(*i); // Get the type for the field. const Type *FDTy = FD->getType().getTypePtr(); if (!FD->isAnonymousStructOrUnion()) { // Remember all fields written by the user. RecFields.push_back(FD); } // If the field is already invalid for some reason, don't emit more // diagnostics about it. if (FD->isInvalidDecl()) { EnclosingDecl->setInvalidDecl(); continue; } // C99 6.7.2.1p2: // A structure or union shall not contain a member with // incomplete or function type (hence, a structure shall not // contain an instance of itself, but may contain a pointer to // an instance of itself), except that the last member of a // structure with more than one named member may have incomplete // array type; such a structure (and any union containing, // possibly recursively, a member that is such a structure) // shall not be a member of a structure or an element of an // array. if (FDTy->isFunctionType()) { // Field declared as a function. Diag(FD->getLocation(), diag::err_field_declared_as_function) << FD->getDeclName(); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } else if (FDTy->isIncompleteArrayType() && Record && ((i + 1 == Fields.end() && !Record->isUnion()) || ((getLangOpts().MicrosoftExt || getLangOpts().CPlusPlus) && (i + 1 == Fields.end() || Record->isUnion())))) { // Flexible array member. // Microsoft and g++ is more permissive regarding flexible array. // It will accept flexible array in union and also // as the sole element of a struct/class. if (getLangOpts().MicrosoftExt) { if (Record->isUnion()) Diag(FD->getLocation(), diag::ext_flexible_array_union_ms) << FD->getDeclName(); else if (Fields.size() == 1) Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_ms) << FD->getDeclName() << Record->getTagKind(); } else if (getLangOpts().CPlusPlus) { if (Record->isUnion()) Diag(FD->getLocation(), diag::ext_flexible_array_union_gnu) << FD->getDeclName(); else if (Fields.size() == 1) Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_gnu) << FD->getDeclName() << Record->getTagKind(); } else if (!getLangOpts().C99) { if (Record->isUnion()) Diag(FD->getLocation(), diag::ext_flexible_array_union_gnu) << FD->getDeclName(); else Diag(FD->getLocation(), diag::ext_c99_flexible_array_member) << FD->getDeclName() << Record->getTagKind(); } else if (NumNamedMembers < 1) { Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) << FD->getDeclName(); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } if (!FD->getType()->isDependentType() && !Context.getBaseElementType(FD->getType()).isPODType(Context)) { Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) << FD->getDeclName() << FD->getType(); FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } // Okay, we have a legal flexible array member at the end of the struct. if (Record) Record->setHasFlexibleArrayMember(true); } else if (!FDTy->isDependentType() && RequireCompleteType(FD->getLocation(), FD->getType(), diag::err_field_incomplete)) { // Incomplete type FD->setInvalidDecl(); EnclosingDecl->setInvalidDecl(); continue; } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { if (FDTTy->getDecl()->hasFlexibleArrayMember()) { // If this is a member of a union, then entire union becomes "flexible". if (Record && Record->isUnion()) { Record->setHasFlexibleArrayMember(true); } else { // If this is a struct/class and this is not the last element, reject // it. Note that GCC supports variable sized arrays in the middle of // structures. if (i + 1 != Fields.end()) Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) << FD->getDeclName() << FD->getType(); else { // We support flexible arrays at the end of structs in // other structs as an extension. Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) << FD->getDeclName(); if (Record) Record->setHasFlexibleArrayMember(true); } } } if (isa<ObjCContainerDecl>(EnclosingDecl) && RequireNonAbstractType(FD->getLocation(), FD->getType(), diag::err_abstract_type_in_decl, AbstractIvarType)) { // Ivars can not have abstract class types FD->setInvalidDecl(); } if (Record && FDTTy->getDecl()->hasObjectMember()) Record->setHasObjectMember(true); if (Record && FDTTy->getDecl()->hasVolatileMember()) Record->setHasVolatileMember(true); } else if (FDTy->isObjCObjectType()) { /// A field cannot be an Objective-c object Diag(FD->getLocation(), diag::err_statically_allocated_object) << FixItHint::CreateInsertion(FD->getLocation(), "*"); QualType T = Context.getObjCObjectPointerType(FD->getType()); FD->setType(T); } else if (getLangOpts().ObjCAutoRefCount && Record && !ARCErrReported && (!getLangOpts().CPlusPlus || Record->isUnion())) { // It's an error in ARC if a field has lifetime. // We don't want to report this in a system header, though, // so we just make the field unavailable. // FIXME: that's really not sufficient; we need to make the type // itself invalid to, say, initialize or copy. QualType T = FD->getType(); Qualifiers::ObjCLifetime lifetime = T.getObjCLifetime(); if (lifetime && lifetime != Qualifiers::OCL_ExplicitNone) { SourceLocation loc = FD->getLocation(); if (getSourceManager().isInSystemHeader(loc)) { if (!FD->hasAttr<UnavailableAttr>()) { FD->addAttr(new (Context) UnavailableAttr(loc, Context, "this system field has retaining ownership")); } } else { Diag(FD->getLocation(), diag::err_arc_objc_object_in_tag) << T->isBlockPointerType() << Record->getTagKind(); } ARCErrReported = true; } } else if (getLangOpts().ObjC1 && getLangOpts().getGC() != LangOptions::NonGC && Record && !Record->hasObjectMember()) { if (FD->getType()->isObjCObjectPointerType() || FD->getType().isObjCGCStrong()) Record->setHasObjectMember(true); else if (Context.getAsArrayType(FD->getType())) { QualType BaseType = Context.getBaseElementType(FD->getType()); if (BaseType->isRecordType() && BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) Record->setHasObjectMember(true); else if (BaseType->isObjCObjectPointerType() || BaseType.isObjCGCStrong()) Record->setHasObjectMember(true); } } if (Record && FD->getType().isVolatileQualified()) Record->setHasVolatileMember(true); // Keep track of the number of named members. if (FD->getIdentifier()) ++NumNamedMembers; } // Okay, we successfully defined 'Record'. if (Record) { bool Completed = false; if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { if (!CXXRecord->isInvalidDecl()) { // Set access bits correctly on the directly-declared conversions. for (CXXRecordDecl::conversion_iterator I = CXXRecord->conversion_begin(), E = CXXRecord->conversion_end(); I != E; ++I) I.setAccess((*I)->getAccess()); if (!CXXRecord->isDependentType()) { if (CXXRecord->hasUserDeclaredDestructor()) { // Adjust user-defined destructor exception spec. if (getLangOpts().CPlusPlus11) AdjustDestructorExceptionSpec(CXXRecord, CXXRecord->getDestructor()); // The Microsoft ABI requires that we perform the destructor body // checks (i.e. operator delete() lookup) at every declaration, as // any translation unit may need to emit a deleting destructor. if (Context.getTargetInfo().getCXXABI().isMicrosoft()) CheckDestructor(CXXRecord->getDestructor()); } // Add any implicitly-declared members to this class. AddImplicitlyDeclaredMembersToClass(CXXRecord); // If we have virtual base classes, we may end up finding multiple // final overriders for a given virtual function. Check for this // problem now. if (CXXRecord->getNumVBases()) { CXXFinalOverriderMap FinalOverriders; CXXRecord->getFinalOverriders(FinalOverriders); for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), MEnd = FinalOverriders.end(); M != MEnd; ++M) { for (OverridingMethods::iterator SO = M->second.begin(), SOEnd = M->second.end(); SO != SOEnd; ++SO) { assert(SO->second.size() > 0 && "Virtual function without overridding functions?"); if (SO->second.size() == 1) continue; // C++ [class.virtual]p2: // In a derived class, if a virtual member function of a base // class subobject has more than one final overrider the // program is ill-formed. Diag(Record->getLocation(), diag::err_multiple_final_overriders) << (const NamedDecl *)M->first << Record; Diag(M->first->getLocation(), diag::note_overridden_virtual_function); for (OverridingMethods::overriding_iterator OM = SO->second.begin(), OMEnd = SO->second.end(); OM != OMEnd; ++OM) Diag(OM->Method->getLocation(), diag::note_final_overrider) << (const NamedDecl *)M->first << OM->Method->getParent(); Record->setInvalidDecl(); } } CXXRecord->completeDefinition(&FinalOverriders); Completed = true; } } } } if (!Completed) Record->completeDefinition(); if (Record->hasAttrs()) CheckAlignasUnderalignment(Record); // Check if the structure/union declaration is a language extension. if (!getLangOpts().CPlusPlus) { bool ZeroSize = true; bool IsEmpty = true; unsigned NonBitFields = 0; for (RecordDecl::field_iterator I = Record->field_begin(), E = Record->field_end(); (NonBitFields == 0 || ZeroSize) && I != E; ++I) { IsEmpty = false; if (I->isUnnamedBitfield()) { if (I->getBitWidthValue(Context) > 0) ZeroSize = false; } else { ++NonBitFields; QualType FieldType = I->getType(); if (FieldType->isIncompleteType() || !Context.getTypeSizeInChars(FieldType).isZero()) ZeroSize = false; } } // Empty structs are an extension in C (C99 6.7.2.1p7), but are allowed in // C++. if (ZeroSize) Diag(RecLoc, diag::warn_zero_size_struct_union_compat) << IsEmpty << Record->isUnion() << (NonBitFields > 1); // Structs without named members are extension in C (C99 6.7.2.1p7), but // are accepted by GCC. if (NonBitFields == 0) { if (IsEmpty) Diag(RecLoc, diag::ext_empty_struct_union) << Record->isUnion(); else Diag(RecLoc, diag::ext_no_named_members_in_struct_union) << Record->isUnion(); } } } else { ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { ID->setEndOfDefinitionLoc(RBrac); // Add ivar's to class's DeclContext. for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { ClsFields[i]->setLexicalDeclContext(ID); ID->addDecl(ClsFields[i]); } // Must enforce the rule that ivars in the base classes may not be // duplicates. if (ID->getSuperClass()) DiagnoseDuplicateIvars(ID, ID->getSuperClass()); } else if (ObjCImplementationDecl *IMPDecl = dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); for (unsigned I = 0, N = RecFields.size(); I != N; ++I) // Ivar declared in @implementation never belongs to the implementation. // Only it is in implementation's lexical context. ClsFields[I]->setLexicalDeclContext(IMPDecl); CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); IMPDecl->setIvarLBraceLoc(LBrac); IMPDecl->setIvarRBraceLoc(RBrac); } else if (ObjCCategoryDecl *CDecl = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { // case of ivars in class extension; all other cases have been // reported as errors elsewhere. // FIXME. Class extension does not have a LocEnd field. // CDecl->setLocEnd(RBrac); // Add ivar's to class extension's DeclContext. // Diagnose redeclaration of private ivars. ObjCInterfaceDecl *IDecl = CDecl->getClassInterface(); for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { if (IDecl) { if (const ObjCIvarDecl *ClsIvar = IDecl->getIvarDecl(ClsFields[i]->getIdentifier())) { Diag(ClsFields[i]->getLocation(), diag::err_duplicate_ivar_declaration); Diag(ClsIvar->getLocation(), diag::note_previous_definition); continue; } for (ObjCInterfaceDecl::known_extensions_iterator Ext = IDecl->known_extensions_begin(), ExtEnd = IDecl->known_extensions_end(); Ext != ExtEnd; ++Ext) { if (const ObjCIvarDecl *ClsExtIvar = Ext->getIvarDecl(ClsFields[i]->getIdentifier())) { Diag(ClsFields[i]->getLocation(), diag::err_duplicate_ivar_declaration); Diag(ClsExtIvar->getLocation(), diag::note_previous_definition); continue; } } } ClsFields[i]->setLexicalDeclContext(CDecl); CDecl->addDecl(ClsFields[i]); } CDecl->setIvarLBraceLoc(LBrac); CDecl->setIvarRBraceLoc(RBrac); } } if (Attr) ProcessDeclAttributeList(S, Record, Attr); } /// \brief Determine whether the given integral value is representable within /// the given type T. static bool isRepresentableIntegerValue(ASTContext &Context, llvm::APSInt &Value, QualType T) { assert(T->isIntegralType(Context) && "Integral type required!"); unsigned BitWidth = Context.getIntWidth(T); if (Value.isUnsigned() || Value.isNonNegative()) { if (T->isSignedIntegerOrEnumerationType()) --BitWidth; return Value.getActiveBits() <= BitWidth; } return Value.getMinSignedBits() <= BitWidth; } // \brief Given an integral type, return the next larger integral type // (or a NULL type of no such type exists). static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { // FIXME: Int128/UInt128 support, which also needs to be introduced into // enum checking below. assert(T->isIntegralType(Context) && "Integral type required!"); const unsigned NumTypes = 4; QualType SignedIntegralTypes[NumTypes] = { Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy }; QualType UnsignedIntegralTypes[NumTypes] = { Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, Context.UnsignedLongLongTy }; unsigned BitWidth = Context.getTypeSize(T); QualType *Types = T->isSignedIntegerOrEnumerationType()? SignedIntegralTypes : UnsignedIntegralTypes; for (unsigned I = 0; I != NumTypes; ++I) if (Context.getTypeSize(Types[I]) > BitWidth) return Types[I]; return QualType(); } EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, EnumConstantDecl *LastEnumConst, SourceLocation IdLoc, IdentifierInfo *Id, Expr *Val) { unsigned IntWidth = Context.getTargetInfo().getIntWidth(); llvm::APSInt EnumVal(IntWidth); QualType EltTy; if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue)) Val = 0; if (Val) Val = DefaultLvalueConversion(Val).take(); if (Val) { if (Enum->isDependentType() || Val->isTypeDependent()) EltTy = Context.DependentTy; else { SourceLocation ExpLoc; if (getLangOpts().CPlusPlus11 && Enum->isFixed() && !getLangOpts().MicrosoftMode) { // C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the // constant-expression in the enumerator-definition shall be a converted // constant expression of the underlying type. EltTy = Enum->getIntegerType(); ExprResult Converted = CheckConvertedConstantExpression(Val, EltTy, EnumVal, CCEK_Enumerator); if (Converted.isInvalid()) Val = 0; else Val = Converted.take(); } else if (!Val->isValueDependent() && !(Val = VerifyIntegerConstantExpression(Val, &EnumVal).take())) { // C99 6.7.2.2p2: Make sure we have an integer constant expression. } else { if (Enum->isFixed()) { EltTy = Enum->getIntegerType(); // In Obj-C and Microsoft mode, require the enumeration value to be // representable in the underlying type of the enumeration. In C++11, // we perform a non-narrowing conversion as part of converted constant // expression checking. if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) { if (getLangOpts().MicrosoftMode) { Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy; Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); } else Diag(IdLoc, diag::err_enumerator_too_large) << EltTy; } else Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); } else if (getLangOpts().CPlusPlus) { // C++11 [dcl.enum]p5: // If the underlying type is not fixed, the type of each enumerator // is the type of its initializing value: // - If an initializer is specified for an enumerator, the // initializing value has the same type as the expression. EltTy = Val->getType(); } else { // C99 6.7.2.2p2: // The expression that defines the value of an enumeration constant // shall be an integer constant expression that has a value // representable as an int. // Complain if the value is not representable in an int. if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) Diag(IdLoc, diag::ext_enum_value_not_int) << EnumVal.toString(10) << Val->getSourceRange() << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { // Force the type of the expression to 'int'. Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).take(); } EltTy = Val->getType(); } } } } if (!Val) { if (Enum->isDependentType()) EltTy = Context.DependentTy; else if (!LastEnumConst) { // C++0x [dcl.enum]p5: // If the underlying type is not fixed, the type of each enumerator // is the type of its initializing value: // - If no initializer is specified for the first enumerator, the // initializing value has an unspecified integral type. // // GCC uses 'int' for its unspecified integral type, as does // C99 6.7.2.2p3. if (Enum->isFixed()) { EltTy = Enum->getIntegerType(); } else { EltTy = Context.IntTy; } } else { // Assign the last value + 1. EnumVal = LastEnumConst->getInitVal(); ++EnumVal; EltTy = LastEnumConst->getType(); // Check for overflow on increment. if (EnumVal < LastEnumConst->getInitVal()) { // C++0x [dcl.enum]p5: // If the underlying type is not fixed, the type of each enumerator // is the type of its initializing value: // // - Otherwise the type of the initializing value is the same as // the type of the initializing value of the preceding enumerator // unless the incremented value is not representable in that type, // in which case the type is an unspecified integral type // sufficient to contain the incremented value. If no such type // exists, the program is ill-formed. QualType T = getNextLargerIntegralType(Context, EltTy); if (T.isNull() || Enum->isFixed()) { // There is no integral type larger enough to represent this // value. Complain, then allow the value to wrap around. EnumVal = LastEnumConst->getInitVal(); EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2); ++EnumVal; if (Enum->isFixed()) // When the underlying type is fixed, this is ill-formed. Diag(IdLoc, diag::err_enumerator_wrapped) << EnumVal.toString(10) << EltTy; else Diag(IdLoc, diag::warn_enumerator_too_large) << EnumVal.toString(10); } else { EltTy = T; } // Retrieve the last enumerator's value, extent that type to the // type that is supposed to be large enough to represent the incremented // value, then increment. EnumVal = LastEnumConst->getInitVal(); EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType()); EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); ++EnumVal; // If we're not in C++, diagnose the overflow of enumerator values, // which in C99 means that the enumerator value is not representable in // an int (C99 6.7.2.2p2). However, we support GCC's extension that // permits enumerator values that are representable in some larger // integral type. if (!getLangOpts().CPlusPlus && !T.isNull()) Diag(IdLoc, diag::warn_enum_value_overflow); } else if (!getLangOpts().CPlusPlus && !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { // Enforce C99 6.7.2.2p2 even when we compute the next value. Diag(IdLoc, diag::ext_enum_value_not_int) << EnumVal.toString(10) << 1; } } } if (!EltTy->isDependentType()) { // Make the enumerator value match the signedness and size of the // enumerator's type. EnumVal = EnumVal.extOrTrunc(Context.getIntWidth(EltTy)); EnumVal.setIsSigned(EltTy->isSignedIntegerOrEnumerationType()); } return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, Val, EnumVal); } Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst, SourceLocation IdLoc, IdentifierInfo *Id, AttributeList *Attr, SourceLocation EqualLoc, Expr *Val) { EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); EnumConstantDecl *LastEnumConst = cast_or_null<EnumConstantDecl>(lastEnumConst); // The scope passed in may not be a decl scope. Zip up the scope tree until // we find one that is. S = getNonFieldDeclScope(S); // Verify that there isn't already something declared with this name in this // scope. NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, ForRedeclaration); if (PrevDecl && PrevDecl->isTemplateParameter()) { // Maybe we will complain about the shadowed template parameter. DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); // Just pretend that we didn't see the previous declaration. PrevDecl = 0; } if (PrevDecl) { // When in C++, we may get a TagDecl with the same name; in this case the // enum constant will 'hide' the tag. assert((getLangOpts().CPlusPlus || !isa<TagDecl>(PrevDecl)) && "Received TagDecl when not in C++!"); if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { if (isa<EnumConstantDecl>(PrevDecl)) Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; else Diag(IdLoc, diag::err_redefinition) << Id; Diag(PrevDecl->getLocation(), diag::note_previous_definition); return 0; } } // C++ [class.mem]p15: // If T is the name of a class, then each of the following shall have a name // different from T: // - every enumerator of every member of class T that is an unscoped // enumerated type if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>( TheEnumDecl->getDeclContext()->getRedeclContext())) if (!TheEnumDecl->isScoped() && Record->getIdentifier() && Record->getIdentifier() == Id) Diag(IdLoc, diag::err_member_name_of_class) << Id; EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val); if (New) { // Process attributes. if (Attr) ProcessDeclAttributeList(S, New, Attr); // Register this decl in the current scope stack. New->setAccess(TheEnumDecl->getAccess()); PushOnScopeChains(New, S); } ActOnDocumentableDecl(New); return New; } // Returns true when the enum initial expression does not trigger the // duplicate enum warning. A few common cases are exempted as follows: // Element2 = Element1 // Element2 = Element1 + 1 // Element2 = Element1 - 1 // Where Element2 and Element1 are from the same enum. static bool ValidDuplicateEnum(EnumConstantDecl *ECD, EnumDecl *Enum) { Expr *InitExpr = ECD->getInitExpr(); if (!InitExpr) return true; InitExpr = InitExpr->IgnoreImpCasts(); if (BinaryOperator *BO = dyn_cast<BinaryOperator>(InitExpr)) { if (!BO->isAdditiveOp()) return true; IntegerLiteral *IL = dyn_cast<IntegerLiteral>(BO->getRHS()); if (!IL) return true; if (IL->getValue() != 1) return true; InitExpr = BO->getLHS(); } // This checks if the elements are from the same enum. DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InitExpr); if (!DRE) return true; EnumConstantDecl *EnumConstant = dyn_cast<EnumConstantDecl>(DRE->getDecl()); if (!EnumConstant) return true; if (cast<EnumDecl>(TagDecl::castFromDeclContext(ECD->getDeclContext())) != Enum) return true; return false; } struct DupKey { int64_t val; bool isTombstoneOrEmptyKey; DupKey(int64_t val, bool isTombstoneOrEmptyKey) : val(val), isTombstoneOrEmptyKey(isTombstoneOrEmptyKey) {} }; static DupKey GetDupKey(const llvm::APSInt& Val) { return DupKey(Val.isSigned() ? Val.getSExtValue() : Val.getZExtValue(), false); } struct DenseMapInfoDupKey { static DupKey getEmptyKey() { return DupKey(0, true); } static DupKey getTombstoneKey() { return DupKey(1, true); } static unsigned getHashValue(const DupKey Key) { return (unsigned)(Key.val * 37); } static bool isEqual(const DupKey& LHS, const DupKey& RHS) { return LHS.isTombstoneOrEmptyKey == RHS.isTombstoneOrEmptyKey && LHS.val == RHS.val; } }; // Emits a warning when an element is implicitly set a value that // a previous element has already been set to. static void CheckForDuplicateEnumValues(Sema &S, ArrayRef<Decl *> Elements, EnumDecl *Enum, QualType EnumType) { if (S.Diags.getDiagnosticLevel(diag::warn_duplicate_enum_values, Enum->getLocation()) == DiagnosticsEngine::Ignored) return; // Avoid anonymous enums if (!Enum->getIdentifier()) return; // Only check for small enums. if (Enum->getNumPositiveBits() > 63 || Enum->getNumNegativeBits() > 64) return; typedef SmallVector<EnumConstantDecl *, 3> ECDVector; typedef SmallVector<ECDVector *, 3> DuplicatesVector; typedef llvm::PointerUnion<EnumConstantDecl*, ECDVector*> DeclOrVector; typedef llvm::DenseMap<DupKey, DeclOrVector, DenseMapInfoDupKey> ValueToVectorMap; DuplicatesVector DupVector; ValueToVectorMap EnumMap; // Populate the EnumMap with all values represented by enum constants without // an initialier. for (unsigned i = 0, e = Elements.size(); i != e; ++i) { EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); // Null EnumConstantDecl means a previous diagnostic has been emitted for // this constant. Skip this enum since it may be ill-formed. if (!ECD) { return; } if (ECD->getInitExpr()) continue; DupKey Key = GetDupKey(ECD->getInitVal()); DeclOrVector &Entry = EnumMap[Key]; // First time encountering this value. if (Entry.isNull()) Entry = ECD; } // Create vectors for any values that has duplicates. for (unsigned i = 0, e = Elements.size(); i != e; ++i) { EnumConstantDecl *ECD = cast<EnumConstantDecl>(Elements[i]); if (!ValidDuplicateEnum(ECD, Enum)) continue; DupKey Key = GetDupKey(ECD->getInitVal()); DeclOrVector& Entry = EnumMap[Key]; if (Entry.isNull()) continue; if (EnumConstantDecl *D = Entry.dyn_cast<EnumConstantDecl*>()) { // Ensure constants are different. if (D == ECD) continue; // Create new vector and push values onto it. ECDVector *Vec = new ECDVector(); Vec->push_back(D); Vec->push_back(ECD); // Update entry to point to the duplicates vector. Entry = Vec; // Store the vector somewhere we can consult later for quick emission of // diagnostics. DupVector.push_back(Vec); continue; } ECDVector *Vec = Entry.get<ECDVector*>(); // Make sure constants are not added more than once. if (*Vec->begin() == ECD) continue; Vec->push_back(ECD); } // Emit diagnostics. for (DuplicatesVector::iterator DupVectorIter = DupVector.begin(), DupVectorEnd = DupVector.end(); DupVectorIter != DupVectorEnd; ++DupVectorIter) { ECDVector *Vec = *DupVectorIter; assert(Vec->size() > 1 && "ECDVector should have at least 2 elements."); // Emit warning for one enum constant. ECDVector::iterator I = Vec->begin(); S.Diag((*I)->getLocation(), diag::warn_duplicate_enum_values) << (*I)->getName() << (*I)->getInitVal().toString(10) << (*I)->getSourceRange(); ++I; // Emit one note for each of the remaining enum constants with // the same value. for (ECDVector::iterator E = Vec->end(); I != E; ++I) S.Diag((*I)->getLocation(), diag::note_duplicate_element) << (*I)->getName() << (*I)->getInitVal().toString(10) << (*I)->getSourceRange(); delete Vec; } } void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, SourceLocation RBraceLoc, Decl *EnumDeclX, ArrayRef<Decl *> Elements, Scope *S, AttributeList *Attr) { EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); QualType EnumType = Context.getTypeDeclType(Enum); if (Attr) ProcessDeclAttributeList(S, Enum, Attr); if (Enum->isDependentType()) { for (unsigned i = 0, e = Elements.size(); i != e; ++i) { EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); if (!ECD) continue; ECD->setType(EnumType); } Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); return; } // TODO: If the result value doesn't fit in an int, it must be a long or long // long value. ISO C does not support this, but GCC does as an extension, // emit a warning. unsigned IntWidth = Context.getTargetInfo().getIntWidth(); unsigned CharWidth = Context.getTargetInfo().getCharWidth(); unsigned ShortWidth = Context.getTargetInfo().getShortWidth(); // Verify that all the values are okay, compute the size of the values, and // reverse the list. unsigned NumNegativeBits = 0; unsigned NumPositiveBits = 0; // Keep track of whether all elements have type int. bool AllElementsInt = true; for (unsigned i = 0, e = Elements.size(); i != e; ++i) { EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); if (!ECD) continue; // Already issued a diagnostic. const llvm::APSInt &InitVal = ECD->getInitVal(); // Keep track of the size of positive and negative values. if (InitVal.isUnsigned() || InitVal.isNonNegative()) NumPositiveBits = std::max(NumPositiveBits, (unsigned)InitVal.getActiveBits()); else NumNegativeBits = std::max(NumNegativeBits, (unsigned)InitVal.getMinSignedBits()); // Keep track of whether every enum element has type int (very commmon). if (AllElementsInt) AllElementsInt = ECD->getType() == Context.IntTy; } // Figure out the type that should be used for this enum. QualType BestType; unsigned BestWidth; // C++0x N3000 [conv.prom]p3: // An rvalue of an unscoped enumeration type whose underlying // type is not fixed can be converted to an rvalue of the first // of the following types that can represent all the values of // the enumeration: int, unsigned int, long int, unsigned long // int, long long int, or unsigned long long int. // C99 6.4.4.3p2: // An identifier declared as an enumeration constant has type int. // The C99 rule is modified by a gcc extension QualType BestPromotionType; bool Packed = Enum->getAttr<PackedAttr>() ? true : false; // -fshort-enums is the equivalent to specifying the packed attribute on all // enum definitions. if (LangOpts.ShortEnums) Packed = true; if (Enum->isFixed()) { BestType = Enum->getIntegerType(); if (BestType->isPromotableIntegerType()) BestPromotionType = Context.getPromotedIntegerType(BestType); else BestPromotionType = BestType; // We don't need to set BestWidth, because BestType is going to be the type // of the enumerators, but we do anyway because otherwise some compilers // warn that it might be used uninitialized. BestWidth = CharWidth; } else if (NumNegativeBits) { // If there is a negative value, figure out the smallest integer type (of // int/long/longlong) that fits. // If it's packed, check also if it fits a char or a short. if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { BestType = Context.SignedCharTy; BestWidth = CharWidth; } else if (Packed && NumNegativeBits <= ShortWidth && NumPositiveBits < ShortWidth) { BestType = Context.ShortTy; BestWidth = ShortWidth; } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { BestType = Context.IntTy; BestWidth = IntWidth; } else { BestWidth = Context.getTargetInfo().getLongWidth(); if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { BestType = Context.LongTy; } else { BestWidth = Context.getTargetInfo().getLongLongWidth(); if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) Diag(Enum->getLocation(), diag::warn_enum_too_large); BestType = Context.LongLongTy; } } BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); } else { // If there is no negative value, figure out the smallest type that fits // all of the enumerator values. // If it's packed, check also if it fits a char or a short. if (Packed && NumPositiveBits <= CharWidth) { BestType = Context.UnsignedCharTy; BestPromotionType = Context.IntTy; BestWidth = CharWidth; } else if (Packed && NumPositiveBits <= ShortWidth) { BestType = Context.UnsignedShortTy; BestPromotionType = Context.IntTy; BestWidth = ShortWidth; } else if (NumPositiveBits <= IntWidth) { BestType = Context.UnsignedIntTy; BestWidth = IntWidth; BestPromotionType = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus) ? Context.UnsignedIntTy : Context.IntTy; } else if (NumPositiveBits <= (BestWidth = Context.getTargetInfo().getLongWidth())) { BestType = Context.UnsignedLongTy; BestPromotionType = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus) ? Context.UnsignedLongTy : Context.LongTy; } else { BestWidth = Context.getTargetInfo().getLongLongWidth(); assert(NumPositiveBits <= BestWidth && "How could an initializer get larger than ULL?"); BestType = Context.UnsignedLongLongTy; BestPromotionType = (NumPositiveBits == BestWidth || !getLangOpts().CPlusPlus) ? Context.UnsignedLongLongTy : Context.LongLongTy; } } // Loop over all of the enumerator constants, changing their types to match // the type of the enum if needed. for (unsigned i = 0, e = Elements.size(); i != e; ++i) { EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); if (!ECD) continue; // Already issued a diagnostic. // Standard C says the enumerators have int type, but we allow, as an // extension, the enumerators to be larger than int size. If each // enumerator value fits in an int, type it as an int, otherwise type it the // same as the enumerator decl itself. This means that in "enum { X = 1U }" // that X has type 'int', not 'unsigned'. // Determine whether the value fits into an int. llvm::APSInt InitVal = ECD->getInitVal(); // If it fits into an integer type, force it. Otherwise force it to match // the enum decl type. QualType NewTy; unsigned NewWidth; bool NewSign; if (!getLangOpts().CPlusPlus && !Enum->isFixed() && isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { NewTy = Context.IntTy; NewWidth = IntWidth; NewSign = true; } else if (ECD->getType() == BestType) { // Already the right type! if (getLangOpts().CPlusPlus) // C++ [dcl.enum]p4: Following the closing brace of an // enum-specifier, each enumerator has the type of its // enumeration. ECD->setType(EnumType); continue; } else { NewTy = BestType; NewWidth = BestWidth; NewSign = BestType->isSignedIntegerOrEnumerationType(); } // Adjust the APSInt value. InitVal = InitVal.extOrTrunc(NewWidth); InitVal.setIsSigned(NewSign); ECD->setInitVal(InitVal); // Adjust the Expr initializer and type. if (ECD->getInitExpr() && !Context.hasSameType(NewTy, ECD->getInitExpr()->getType())) ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, CK_IntegralCast, ECD->getInitExpr(), /*base paths*/ 0, VK_RValue)); if (getLangOpts().CPlusPlus) // C++ [dcl.enum]p4: Following the closing brace of an // enum-specifier, each enumerator has the type of its // enumeration. ECD->setType(EnumType); else ECD->setType(NewTy); } Enum->completeDefinition(BestType, BestPromotionType, NumPositiveBits, NumNegativeBits); // If we're declaring a function, ensure this decl isn't forgotten about - // it needs to go into the function scope. if (InFunctionDeclarator) DeclsInPrototypeScope.push_back(Enum); CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType); // Now that the enum type is defined, ensure it's not been underaligned. if (Enum->hasAttrs()) CheckAlignasUnderalignment(Enum); } Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr, SourceLocation StartLoc, SourceLocation EndLoc) { StringLiteral *AsmString = cast<StringLiteral>(expr); FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, AsmString, StartLoc, EndLoc); CurContext->addDecl(New); return New; } DeclResult Sema::ActOnModuleImport(SourceLocation AtLoc, SourceLocation ImportLoc, ModuleIdPath Path) { Module *Mod = PP.getModuleLoader().loadModule(ImportLoc, Path, Module::AllVisible, /*IsIncludeDirective=*/false); if (!Mod) return true; SmallVector<SourceLocation, 2> IdentifierLocs; Module *ModCheck = Mod; for (unsigned I = 0, N = Path.size(); I != N; ++I) { // If we've run out of module parents, just drop the remaining identifiers. // We need the length to be consistent. if (!ModCheck) break; ModCheck = ModCheck->Parent; IdentifierLocs.push_back(Path[I].second); } ImportDecl *Import = ImportDecl::Create(Context, Context.getTranslationUnitDecl(), AtLoc.isValid()? AtLoc : ImportLoc, Mod, IdentifierLocs); Context.getTranslationUnitDecl()->addDecl(Import); return Import; } void Sema::createImplicitModuleImport(SourceLocation Loc, Module *Mod) { // Create the implicit import declaration. TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl(); ImportDecl *ImportD = ImportDecl::CreateImplicit(getASTContext(), TU, Loc, Mod, Loc); TU->addDecl(ImportD); Consumer.HandleImplicitImportDecl(ImportD); // Make the module visible. PP.getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, Loc, /*Complain=*/false); } void Sema::ActOnPragmaRedefineExtname(IdentifierInfo* Name, IdentifierInfo* AliasName, SourceLocation PragmaLoc, SourceLocation NameLoc, SourceLocation AliasNameLoc) { Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); AsmLabelAttr *Attr = ::new (Context) AsmLabelAttr(AliasNameLoc, Context, AliasName->getName()); if (PrevDecl) PrevDecl->addAttr(Attr); else (void)ExtnameUndeclaredIdentifiers.insert( std::pair<IdentifierInfo*,AsmLabelAttr*>(Name, Attr)); } void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, SourceLocation PragmaLoc, SourceLocation NameLoc) { Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); if (PrevDecl) { PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); } else { (void)WeakUndeclaredIdentifiers.insert( std::pair<IdentifierInfo*,WeakInfo> (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); } } void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, IdentifierInfo* AliasName, SourceLocation PragmaLoc, SourceLocation NameLoc, SourceLocation AliasNameLoc) { Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, LookupOrdinaryName); WeakInfo W = WeakInfo(Name, NameLoc); if (PrevDecl) { if (!PrevDecl->hasAttr<AliasAttr>()) if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) DeclApplyPragmaWeak(TUScope, ND, W); } else { (void)WeakUndeclaredIdentifiers.insert( std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); } } Decl *Sema::getObjCDeclContext() const { return (dyn_cast_or_null<ObjCContainerDecl>(CurContext)); } AvailabilityResult Sema::getCurContextAvailability() const { const Decl *D = cast<Decl>(getCurObjCLexicalContext()); return D->getAvailability(); }