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Diffstat (limited to 'contrib/llvm/tools/clang/lib/Sema/SemaDecl.cpp')
| -rw-r--r-- | contrib/llvm/tools/clang/lib/Sema/SemaDecl.cpp | 13006 |
1 files changed, 13006 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/Sema/SemaDecl.cpp b/contrib/llvm/tools/clang/lib/Sema/SemaDecl.cpp new file mode 100644 index 0000000..328ce70 --- /dev/null +++ b/contrib/llvm/tools/clang/lib/Sema/SemaDecl.cpp @@ -0,0 +1,13006 @@ +//===--- 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/ASTLambda.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 "clang/Sema/Template.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::annot_decltype: + 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. +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) { + diagnoseTypo(Correction, + PDiag(diag::err_unknown_type_or_class_name_suggest) + << Result.getLookupName() << isClassName); + 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)) { + if (Corrected.isKeyword()) { + // We corrected to a keyword. + diagnoseTypo(Corrected, PDiag(diag::err_unknown_typename_suggest) << II); + II = Corrected.getCorrectionAsIdentifierInfo(); + } else { + // We found a similarly-named type or interface; suggest that. + if (!SS || !SS->isSet()) { + diagnoseTypo(Corrected, + PDiag(diag::err_unknown_typename_suggest) << II); + } else if (DeclContext *DC = computeDeclContext(*SS, false)) { + std::string CorrectedStr(Corrected.getAsString(getLangOpts())); + bool DroppedSpecifier = Corrected.WillReplaceSpecifier() && + II->getName().equals(CorrectedStr); + diagnoseTypo(Corrected, + PDiag(diag::err_unknown_nested_typename_suggest) + << II << DC << DroppedSpecifier << SS->getRange()); + } else { + llvm_unreachable("could not have corrected a typo here"); + } + + CXXScopeSpec tmpSS; + if (Corrected.getCorrectionSpecifier()) + tmpSS.MakeTrivial(Context, Corrected.getCorrectionSpecifier(), + SourceRange(IILoc)); + SuggestedType = getTypeName(*Corrected.getCorrectionAsIdentifierInfo(), + IILoc, S, tmpSS.isSet() ? &tmpSS : 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.get(); + 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; + + 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()) { + diagnoseTypo(Corrected, PDiag(UnqualifiedDiag) << Name); + } else {// FIXME: is this even reachable? Test it. + std::string CorrectedStr(Corrected.getAsString(getLangOpts())); + bool DroppedSpecifier = Corrected.WillReplaceSpecifier() && + Name->getName().equals(CorrectedStr); + diagnoseTypo(Corrected, PDiag(QualifiedDiag) + << Name << computeDeclContext(SS, false) + << DroppedSpecifier << SS.getRange()); + } + + // Update the name, so that the caller has the new name. + Name = Corrected.getCorrectionAsIdentifierInfo(); + + // Typo correction corrected to a keyword. + if (Corrected.isKeyword()) + return Name; + + // Also update the LookupResult... + // FIXME: This should probably go away at some point + Result.clear(); + Result.setLookupName(Corrected.getCorrection()); + if (FirstDecl) + Result.addDecl(FirstDecl); + + // 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. + // A Lambda call operator whose parent is a class must not be treated + // as an inline member function. A Lambda can be used legally + // either as an in-class member initializer or a default argument. These + // are parsed once the class has been marked complete and so the containing + // context would be the nested class (when the lambda is defined in one); + // If the class is not complete, then the lambda is being used in an + // ill-formed fashion (such as to specify the width of a bit-field, or + // in an array-bound) - in which case we still want to return the + // lexically containing DC (which could be a nested class). + if (isa<FunctionDecl>(DC) && !isLambdaCallOperator(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 = 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() && 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++, unless they + // are function-local declarations. + if (getLangOpts().CPlusPlus && D->isOutOfLine() && + !D->getDeclContext()->getRedeclContext()->Equals( + D->getLexicalDeclContext()->getRedeclContext()) && + !D->getLexicalDeclContext()->isFunctionOrMethod()) + 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 = 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(); +} + +// FIXME: This needs to be refactored; some other isInMainFile users want +// these semantics. +static bool isMainFileLoc(const Sema &S, SourceLocation Loc) { + if (S.TUKind != TU_Complete) + return false; + return S.SourceMgr.isInMainFile(Loc); +} + +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 defined in headers; don't warn. + if (FD->isInlineSpecified() && + !isMainFileLoc(*this, FD->getLocation())) + return false; + } + + if (FD->doesThisDeclarationHaveABody() && + Context.DeclMustBeEmitted(FD)) + return false; + } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { + // Constants and utility variables are defined in headers with internal + // linkage; don't warn. (Unlike functions, there isn't a convenient marker + // like "inline".) + if (!isMainFileLoc(*this, VD->getLocation())) + return false; + + if (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->getFirstDecl(); + 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->getFirstDecl(); + 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); + } + DiagnoseUnusedBackingIvarInAccessor(S); +} + +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)) { + diagnoseTypo(C, PDiag(diag::err_undef_interface_suggest) << Id); + IDecl = C.getCorrectionDeclAs<ObjCInterfaceDecl>(); + 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() && 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); + } + + DeclContext *Parent = Context.getTranslationUnitDecl(); + if (getLangOpts().CPlusPlus) { + LinkageSpecDecl *CLinkageDecl = + LinkageSpecDecl::Create(Context, Parent, Loc, Loc, + LinkageSpecDecl::lang_c, false); + Parent->addDecl(CLinkageDecl); + Parent = CLinkageDecl; + } + + FunctionDecl *New = FunctionDecl::Create(Context, + Parent, + 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); + RegisterLocallyScopedExternCDecl(New, S); + + // 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 = Parent; + 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 and merge attributes if + // the old declaration was a typedef. + if (TypedefNameDecl *Typedef = dyn_cast<TypedefNameDecl>(Old)) { + New->setPreviousDecl(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)) { + const VarDecl *Def = VD->getDefinition(); + if (Def) + return Def; + return VD->getActingDefinition(); + } + if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { + const FunctionDecl* Def; + if (FD->isDefined(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 (isa<AliasAttr>(NewAttribute)) { + if (FunctionDecl *FD = dyn_cast<FunctionDecl>(New)) + S.CheckForFunctionRedefinition(FD, cast<FunctionDecl>(Def)); + else { + VarDecl *VD = cast<VarDecl>(New); + unsigned Diag = cast<VarDecl>(Def)->isThisDeclarationADefinition() == + VarDecl::TentativeDefinition + ? diag::err_alias_after_tentative + : diag::err_redefinition; + S.Diag(VD->getLocation(), Diag) << VD->getDeclName(); + S.Diag(Def->getLocation(), diag::note_previous_definition); + VD->setInvalidDecl(); + } + ++I; + continue; + } + + if (const VarDecl *VD = dyn_cast<VarDecl>(Def)) { + // Tentative definitions are only interesting for the alias check above. + if (VD->isThisDeclarationADefinition() != VarDecl::Definition) { + ++I; + continue; + } + } + + 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 (UsedAttr *OldAttr = Old->getMostRecentDecl()->getAttr<UsedAttr>()) { + UsedAttr *NewAttr = OldAttr->clone(Context); + NewAttr->setInherited(true); + New->addAttr(NewAttr); + } + + 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; + } + } + + // Already handled. + if (isa<UsedAttr>(*i)) + continue; + + 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())->getFirstDecl(); + 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); +} + +const AttributedType *Sema::getCallingConvAttributedType(QualType T) const { + const AttributedType *AT = T->getAs<AttributedType>(); + while (AT && !AT->isCallingConv()) + AT = AT->getModifiedType()->getAs<AttributedType>(); + return AT; +} + +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, + bool MergeTypeWithOld) { + // 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; + + // 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, all following decls assume 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. + // + // To test if either decl has an explicit calling convention, we look for + // AttributedType sugar nodes on the type as written. If they are missing or + // were canonicalized away, we assume the calling convention was implicit. + // + // Note also that we DO NOT return at this point, because we still have + // other tests to run. + QualType OldQType = Context.getCanonicalType(Old->getType()); + QualType NewQType = Context.getCanonicalType(New->getType()); + const FunctionType *OldType = cast<FunctionType>(OldQType); + const FunctionType *NewType = cast<FunctionType>(NewQType); + FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); + FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); + bool RequiresAdjustment = false; + + if (OldTypeInfo.getCC() != NewTypeInfo.getCC()) { + FunctionDecl *First = Old->getFirstDecl(); + const FunctionType *FT = + First->getType().getCanonicalType()->castAs<FunctionType>(); + FunctionType::ExtInfo FI = FT->getExtInfo(); + bool NewCCExplicit = getCallingConvAttributedType(New->getType()); + if (!NewCCExplicit) { + // Inherit the CC from the previous declaration if it was specified + // there but not here. + NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); + RequiresAdjustment = true; + } else { + // Calling conventions aren't compatible, so complain. + bool FirstCCExplicit = getCallingConvAttributedType(First->getType()); + Diag(New->getLocation(), diag::err_cconv_change) + << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) + << !FirstCCExplicit + << (!FirstCCExplicit ? "" : + FunctionType::getNameForCallConv(FI.getCC())); + + // Put the note on the first decl, since it is the one that matters. + Diag(First->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) { + const FunctionType *AdjustedType = New->getType()->getAs<FunctionType>(); + AdjustedType = Context.adjustFunctionType(AdjustedType, NewTypeInfo); + New->setType(QualType(AdjustedType, 0)); + NewQType = Context.getCanonicalType(New->getType()); + NewType = cast<FunctionType>(NewQType); + } + + // 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]p13: + // 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) && + !((NewQType->isDependentType() || OldQType->isDependentType()) && + New->isLocalExternDecl())) { + 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->isDependentType() ? Context.DependentTy + : OldAT->getDeducedType())); + NewQType = Context.getCanonicalType( + SubstAutoType(NewQType, + OldAT->isDependentType() ? Context.DependentTy + : 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->getFirstDecl()->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->getFirstDecl()->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)) { + // As a special case, retain the language linkage from previous + // declarations of a friend function as an extension. + // + // This liberal interpretation of C++ [class.friend]p3 matches GCC/MSVC + // and is useful because there's otherwise no way to specify language + // linkage within class scope. + // + // Check cautiously as the friend object kind isn't yet complete. + if (New->getFriendObjectKind() != Decl::FOK_None) { + Diag(New->getLocation(), diag::ext_retained_language_linkage) << New; + Diag(Old->getLocation(), PrevDiag); + } else { + Diag(New->getLocation(), diag::err_different_language_linkage) << New; + Diag(Old->getLocation(), PrevDiag); + return true; + } + } + + if (OldQTypeForComparison == NewQType) + return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld); + + if ((NewQType->isDependentType() || OldQType->isDependentType()) && + New->isLocalExternDecl()) { + // It's OK if we couldn't merge types for a local function declaraton + // if either the old or new type is dependent. We'll merge the types + // when we instantiate the function. + return false; + } + + // 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 (MergeTypeWithOld && 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, MergeTypeWithOld); + } + + // 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); + } + + if (MergeTypeWithOld) + New->setType(Context.getFunctionType(MergedReturn, ArgTypes, + OldProto->getExtProtoInfo())); + return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld); + } + + // 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->getLexicalDeclContext()->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 from 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, bool MergeTypeWithOld) { + // Merge the attributes + mergeDeclAttributes(New, Old); + + // Merge "pure" flag. + if (Old->isPure()) + New->setPure(); + + // Merge "used" flag. + if (Old->getMostRecentDecl()->isUsed(false)) + New->setIsUsed(); + + // 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. Per C11 6.2.7/4, only update the type if the old decl + // was visible. + QualType Merged = Context.mergeTypes(Old->getType(), New->getType()); + if (!Merged.isNull() && MergeTypeWithOld) + 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 MergeTypeWithOld) { + 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 { + // C 6.2.7p2: + // All declarations that refer to the same object or function shall have + // compatible type. + MergedT = Context.mergeTypes(New->getType(), Old->getType()); + } + if (MergedT.isNull()) { + // It's OK if we couldn't merge types if either type is dependent, for a + // block-scope variable. In other cases (static data members of class + // templates, variable templates, ...), we require the types to be + // equivalent. + // FIXME: The C++ standard doesn't say anything about this. + if ((New->getType()->isDependentType() || + Old->getType()->isDependentType()) && New->isLocalVarDecl()) { + // If the old type was dependent, we can't merge with it, so the new type + // becomes dependent for now. We'll reproduce the original type when we + // instantiate the TypeSourceInfo for the variable. + if (!New->getType()->isDependentType() && MergeTypeWithOld) + New->setType(Context.DependentTy); + return; + } + + // FIXME: Even if this merging succeeds, some other non-visible declaration + // of this variable might have an incompatible type. For instance: + // + // extern int arr[]; + // void f() { extern int arr[2]; } + // void g() { extern int arr[3]; } + // + // Neither C nor C++ requires a diagnostic for this, but we should still try + // to diagnose it. + 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 an extern declaration in a different scope. + if (MergeTypeWithOld) + New->setType(MergedT); +} + +static bool mergeTypeWithPrevious(Sema &S, VarDecl *NewVD, VarDecl *OldVD, + LookupResult &Previous) { + // 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. + // + // If the variable isn't visible, we do not merge with its type. + if (Previous.isShadowed()) + return false; + + if (S.getLangOpts().CPlusPlus) { + // C++11 [dcl.array]p3: + // If there is a preceding declaration of the entity in the same + // scope in which the bound was specified, an omitted array bound + // is taken to be the same as in that earlier declaration. + return NewVD->isPreviousDeclInSameBlockScope() || + (!OldVD->getLexicalDeclContext()->isFunctionOrMethod() && + !NewVD->getLexicalDeclContext()->isFunctionOrMethod()); + } else { + // If the old declaration was function-local, don't merge with its + // type unless we're in the same function. + return !OldVD->getLexicalDeclContext()->isFunctionOrMethod() || + OldVD->getLexicalDeclContext() == NewVD->getLexicalDeclContext(); + } +} + +/// 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) { + // 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 or variable template. + VarDecl *Old = 0; + if (Previous.isSingleResult() && + (Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { + if (New->getDescribedVarTemplate()) + Old = Old->getDescribedVarTemplate() ? Old : 0; + else + Old = Old->getDescribedVarTemplate() ? 0 : Old; + } + if (!Old) { + 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, mergeTypeWithPrevious(*this, New, Old, Previous)); + + 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->getMostRecentDecl()->isUsed(false)) + New->setIsUsed(); + + // Keep a chain of previous declarations. + New->setPreviousDecl(Old); + + // Inherit access appropriately. + New->setAccess(Old->getAccess()); + + if (VarTemplateDecl *VTD = New->getDescribedVarTemplate()) { + if (New->isStaticDataMember() && New->isOutOfLine()) + VTD->setAccess(New->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 (!S.Context.getLangOpts().CPlusPlus) + return; + + 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) || isa<CapturedDecl>(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 if (isa<BlockDecl>(Cur)) + Diag(Loc, diag::err_invalid_declarator_in_block) + << 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 || isa<EnumDecl>(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; + bool CreateBuiltins = 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 the declaration we're planning to build will be declared with + // external linkage in the translation unit, create any builtin with + // the same name. + if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) + /* Do nothing*/; + else if (CurContext->isFunctionOrMethod() && + (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern || + R->isFunctionType())) { + IsLinkageLookup = true; + CreateBuiltins = + CurContext->getEnclosingNamespaceContext()->isTranslationUnit(); + } else if (CurContext->getRedeclContext()->isTranslationUnit() && + D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) + CreateBuiltins = true; + + if (IsLinkageLookup) + Previous.clear(LookupRedeclarationWithLinkage); + + LookupName(Previous, S, CreateBuiltins); + } 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())) { + // Only make a locally-scoped extern declaration visible if it is the first + // declaration of this entity. Qualified lookup for such an entity should + // only find this declaration if there is no visible declaration of it. + bool AddToContext = !D.isRedeclaration() || !New->isLocalExternDecl(); + PushOnScopeChains(New, S, AddToContext); + if (!AddToContext) + CurContext->addHiddenDecl(New); + } + + 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 ? 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"); +} + +/// Adjust the \c DeclContext for a function or variable that might be a +/// function-local external declaration. +bool Sema::adjustContextForLocalExternDecl(DeclContext *&DC) { + if (!DC->isFunctionOrMethod()) + return false; + + // If this is a local extern function or variable declared within a function + // template, don't add it into the enclosing namespace scope until it is + // instantiated; it might have a dependent type right now. + if (DC->isDependentContext()) + return true; + + // C++11 [basic.link]p7: + // When a block scope declaration of an entity with linkage is not found to + // refer to some other declaration, then that entity is a member of the + // innermost enclosing namespace. + // + // Per C++11 [namespace.def]p6, the innermost enclosing namespace is a + // semantically-enclosing namespace, not a lexically-enclosing one. + while (!DC->isFileContext() && !isa<LinkageSpecDecl>(DC)) + DC = DC->getParent(); + return true; +} + +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()); + + DeclContext *OriginalDC = DC; + bool IsLocalExternDecl = SC == SC_Extern && + adjustContextForLocalExternDecl(DC); + + 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 IsVariableTemplate = false; + VarTemplateDecl *PrevVarTemplate = 0; + VarDecl *NewVD = 0; + VarTemplateDecl *NewTemplate = 0; + if (!getLangOpts().CPlusPlus) { + NewVD = VarDecl::Create(Context, DC, D.getLocStart(), + D.getIdentifierLoc(), II, + R, TInfo, SC); + + if (D.isInvalidType()) + NewVD->setInvalidDecl(); + } else { + bool Invalid = false; + + 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. + TemplateParameterList *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. + IsVariableTemplate = true; + + // 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_decl_does_not_match) + << Name << DC << /*IsDefinition*/true + << 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 is supposed to be a variable template, create it as such. + if (IsVariableTemplate) { + NewTemplate = + VarTemplateDecl::Create(Context, DC, D.getIdentifierLoc(), Name, + TemplateParams, NewVD, PrevVarTemplate); + NewVD->setDescribedVarTemplate(NewTemplate); + } + + // 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(); + if (NewTemplate) + NewTemplate->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 (NewTemplate) + NewTemplate->setLexicalDeclContext(CurContext); + + if (IsLocalExternDecl) + NewVD->setLocalExternDecl(); + + 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(); + if (NewTemplate) + NewTemplate->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. + 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, OriginalDC, S, shouldConsiderLinkage(NewVD), + IsExplicitSpecialization || IsVariableTemplateSpecialization); + + // Check whether the previous declaration is in the same block scope. This + // affects whether we merge types with it, per C++11 [dcl.array]p3. + if (getLangOpts().CPlusPlus && + NewVD->isLocalVarDecl() && NewVD->hasExternalStorage()) + NewVD->setPreviousDeclInSameBlockScope( + Previous.isSingleResult() && !Previous.isShadowed() && + isDeclInScope(Previous.getFoundDecl(), OriginalDC, S, false)); + + 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. + 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->isFirstDecl() && !NewVD->isInvalidDecl() && + isIncompleteDeclExternC(*this, NewVD)) + RegisterLocallyScopedExternCDecl(NewVD, S); + + if (getLangOpts().CPlusPlus && NewVD->isStaticLocal()) { + Decl *ManglingContextDecl; + if (MangleNumberingContext *MCtx = + getCurrentMangleNumberContext(NewVD->getDeclContext(), + ManglingContextDecl)) { + Context.setManglingNumber(NewVD, MCtx->getManglingNumber(NewVD)); + } + } + + // If we are providing an explicit specialization of a static variable + // template, make a note of that. + if (PrevVarTemplate && PrevVarTemplate->getInstantiatedFromMemberTemplate()) + PrevVarTemplate->setMemberSpecialization(); + + if (NewTemplate) { + ActOnDocumentableDecl(NewTemplate); + return NewTemplate; + } + + return NewVD; +} + +/// \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->getFirstDecl(); + else + Prev = cast<VarDecl>(Prev)->getFirstDecl(); + + 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. We don't need this in C++, because + // we find local extern decls in the surrounding file-scope DeclContext. + 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. + if (Previous.empty() && + checkForConflictWithNonVisibleExternC(*this, NewVD, Previous)) + Previous.setShadowed(); + + // Filter out any non-conflicting previous declarations. + filterNonConflictingPreviousDecls(Context, NewVD, Previous); + + if (!Previous.empty()) { + MergeVarDecl(NewVD, Previous); + 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, bool IsLocalFriend, Scope *S) { + DeclarationName Name = NewFD->getDeclName(); + DeclContext *NewDC = NewFD->getDeclContext(); + SmallVector<unsigned, 1> MismatchedParams; + SmallVector<std::pair<FunctionDecl *, unsigned>, 1> NearMatches; + TypoCorrection Correction; + bool IsDefinition = ExtraArgs.D.isFunctionDefinition(); + unsigned DiagMsg = IsLocalFriend ? diag::err_no_matching_local_friend + : diag::err_member_decl_does_not_match; + LookupResult Prev(SemaRef, Name, NewFD->getLocation(), + IsLocalFriend ? Sema::LookupLocalFriendName + : Sema::LookupOrdinaryName, + Sema::ForRedeclaration); + + NewFD->setInvalidDecl(); + if (IsLocalFriend) + SemaRef.LookupName(Prev, S); + else + 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(), S, + &ExtraArgs.D.getCXXScopeSpec(), Validator, + IsLocalFriend ? 0 : NewDC))) { + // 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(); + + NamedDecl *Result; + // Retry building the function declaration with the new previous + // declarations, and with errors suppressed. + { + // Trap errors. + Sema::SFINAETrap Trap(SemaRef); + + // TODO: Refactor ActOnFunctionDeclarator so that we can call only the + // pieces need to verify the typo-corrected C++ declaration 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()) + Result = 0; + } + + if (Result) { + // Determine which correction we picked. + Decl *Canonical = Result->getCanonicalDecl(); + for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); + I != E; ++I) + if ((*I)->getCanonicalDecl() == Canonical) + Correction.setCorrectionDecl(*I); + + SemaRef.diagnoseTypo( + Correction, + SemaRef.PDiag(IsLocalFriend + ? diag::err_no_matching_local_friend_suggest + : diag::err_member_decl_does_not_match_suggest) + << Name << NewDC << IsDefinition); + return Result; + } + + // Pretend the typo correction never occurred + ExtraArgs.D.SetIdentifier(Name.getAsIdentifierInfo(), + ExtraArgs.D.getIdentifierLoc()); + ExtraArgs.D.setRedeclaration(wasRedeclaration); + Previous.clear(); + Previous.setLookupName(Name); + } + + SemaRef.Diag(NewFD->getLocation(), DiagMsg) + << Name << NewDC << IsDefinition << 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; + CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD); + bool FDisConst = MD && MD->isConst(); + bool IsMember = MD || !IsLocalFriend; + + // FIXME: These notes are poorly worded for the local friend case. + if (unsigned Idx = NearMatch->second) { + ParmVarDecl *FDParam = FD->getParamDecl(Idx-1); + SourceLocation Loc = FDParam->getTypeSpecStartLoc(); + if (Loc.isInvalid()) Loc = FD->getLocation(); + SemaRef.Diag(Loc, IsMember ? diag::note_member_def_close_param_match + : diag::note_local_decl_close_param_match) + << Idx << FDParam->getType() + << NewFD->getParamDecl(Idx - 1)->getType(); + } else if (FDisConst != NewFDisConst) { + SemaRef.Diag(FD->getLocation(), diag::note_member_def_close_const_match) + << NewFDisConst << FD->getSourceRange().getEnd(); + } else + SemaRef.Diag(FD->getLocation(), + IsMember ? diag::note_member_def_close_match + : diag::note_local_decl_close_match); + } + return 0; +} + +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); + + if (D.isFirstDeclarationOfMember()) + adjustMemberFunctionCC(R, D.isStaticMember()); + + bool isFriend = false; + FunctionTemplateDecl *FunctionTemplate = 0; + bool isExplicitSpecialization = false; + bool isFunctionTemplateSpecialization = false; + + bool isDependentClassScopeExplicitSpecialization = false; + bool HasExplicitTemplateArgs = false; + TemplateArgumentListInfo TemplateArgs; + + bool isVirtualOkay = false; + + DeclContext *OriginalDC = DC; + bool IsLocalExternDecl = adjustContextForLocalExternDecl(DC); + + FunctionDecl *NewFD = CreateNewFunctionDecl(*this, D, DC, R, TInfo, SC, + isVirtualOkay); + if (!NewFD) return 0; + + if (OriginalLexicalContext && OriginalLexicalContext->isObjCContainer()) + NewFD->setTopLevelDeclInObjCContainer(); + + // Set the lexical context. If this is a function-scope declaration, or 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); + + if (IsLocalExternDecl) + NewFD->setLocalExternDecl(); + + 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(); + + // 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); + } + + if (getLangOpts().CPlusPlus1y && + (NewFD->isDependentContext() || + (isFriend && CurContext->isDependentContext())) && + NewFD->getResultType()->isUndeducedType()) { + // If the function template is referenced directly (for instance, as a + // member of the current instantiation), pretend it has a dependent type. + // This is not really justified by the standard, but is the only sane + // thing to do. + // FIXME: For a friend function, we have not marked the function as being + // a friend yet, so 'isDependentContext' on the FD doesn't work. + const FunctionProtoType *FPT = + NewFD->getType()->castAs<FunctionProtoType>(); + QualType Result = SubstAutoType(FPT->getResultType(), + Context.DependentTy); + NewFD->setType(Context.getFunctionType(Result, FPT->getArgTypes(), + FPT->getExtProtoInfo())); + } + + // 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, OriginalDC, 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)); + + // 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); + + 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); + // Attach the attribute to the new decl. Don't apply the attribute if it + // returns an instance of the class (e.g. assignment operators). + if (!MD || MD->getParent() != Ret) { + 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() && NewFD->isMSVCRTEntryPoint()) + CheckMSVCRTEntryPoint(NewFD); + + if (!NewFD->isInvalidDecl()) + D.setRedeclaration(CheckFunctionDeclaration(S, NewFD, Previous, + isExplicitSpecialization)); + else if (!Previous.empty()) + // Make graceful recovery from an invalid redeclaration. + D.setRedeclaration(true); + assert((NewFD->isInvalidDecl() || !D.isRedeclaration() || + Previous.getResultKind() != LookupResult::FoundOverloaded) && + "previous declaration set still overloaded"); + } else { + // C++11 [replacement.functions]p3: + // The program's definitions shall not be specified as inline. + // + // N.B. We diagnose declarations instead of definitions per LWG issue 2340. + // + // Suppress the diagnostic if the function is __attribute__((used)), since + // that forces an external definition to be emitted. + if (D.getDeclSpec().isInlineSpecified() && + NewFD->isReplaceableGlobalAllocationFunction() && + !NewFD->hasAttr<UsedAttr>()) + Diag(D.getDeclSpec().getInlineSpecLoc(), + diag::ext_operator_new_delete_declared_inline) + << NewFD->getDeclName(); + + // 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() && NewFD->isMSVCRTEntryPoint()) + CheckMSVCRTEntryPoint(NewFD); + + 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, false, 0)) { + 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, true, S)) { + 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( + Context.getDefaultCallingConvention(true, false)); + 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->isFirstDecl() && !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"); + + // Determine whether the type of this function should be merged with + // a previous visible declaration. This never happens for functions in C++, + // and always happens in C if the previous declaration was visible. + bool MergeTypeWithPrevious = !getLangOpts().CPlusPlus && + !Previous.isShadowed(); + + // 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(); + MergeTypeWithPrevious = false; + + // ... 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, MergeTypeWithPrevious)) { + 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->getFirstDecl()); + 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); + } + + if (getLangOpts().OpenCL) { + Diag(FD->getLocation(), diag::err_opencl_no_main) + << FD->hasAttr<OpenCLKernelAttr>(); + FD->setInvalidDecl(); + return; + } + + 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_mainlike_template_decl) << FD->getName(); + FD->setInvalidDecl(); + } +} + +void Sema::CheckMSVCRTEntryPoint(FunctionDecl *FD) { + QualType T = FD->getType(); + assert(T->isFunctionType() && "function decl is not of function type"); + const FunctionType *FT = T->castAs<FunctionType>(); + + // Set an implicit return of 'zero' if the function can return some integral, + // enumeration, pointer or nullptr type. + if (FT->getResultType()->isIntegralOrEnumerationType() || + FT->getResultType()->isAnyPointerType() || + FT->getResultType()->isNullPtrType()) + // DllMain is exempt because a return value of zero means it failed. + if (FD->getName() != "DllMain") + FD->setHasImplicitReturnZero(true); + + if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { + Diag(FD->getLocation(), diag::err_mainlike_template_decl) << FD->getName(); + 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(), + VDecl->isInitCapture() ? diag::err_init_capture_no_expression + : 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(), + VDecl->isInitCapture() + ? diag::err_init_capture_multiple_expressions + : 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()) { + // We never need to merge the type, because we cannot form an incomplete + // array of auto, nor deduce such a type. + MergeVarDeclTypes(VDecl, Old, /*MergeTypeWithPrevious*/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())) && + !isTemplateInstantiation(VDecl->getTemplateSpecializationKind())) + 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->isFirstDecl()) + 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() && var->hasLinkage() && + 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; + + if (UsedAttr *Attr = VD->getAttr<UsedAttr>()) { + if (!Attr->isInherited() && !VD->isThisDeclarationADefinition()) { + Diag(Attr->getLocation(), diag::warn_attribute_ignored) << "used"; + VD->dropAttr<UsedAttr>(); + } + } + + if (!VD->isInvalidDecl() && + VD->isThisDeclarationADefinition() == VarDecl::TentativeDefinition) { + if (const VarDecl *Def = VD->getDefinition()) { + if (Def->hasAttr<AliasAttr>()) { + Diag(VD->getLocation(), diag::err_tentative_after_alias) + << VD->getDeclName(); + Diag(Def->getLocation(), diag::note_previous_definition); + VD->setInvalidDecl(); + } + } + } + + 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()); + + DeclaratorDecl *FirstDeclaratorInGroup = 0; + for (unsigned i = 0, e = Group.size(); i != e; ++i) + if (Decl *D = Group[i]) { + if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)) + if (!FirstDeclaratorInGroup) + FirstDeclaratorInGroup = DD; + Decls.push_back(D); + } + + if (DeclSpec::isDeclRep(DS.getTypeSpecType())) { + if (TagDecl *Tag = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl())) { + HandleTagNumbering(*this, Tag); + if (!Tag->hasNameForLinkage() && !Tag->hasDeclaratorForAnonDecl()) + Tag->setDeclaratorForAnonDecl(FirstDeclaratorInGroup); + } + } + + 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->getLexicalDeclContext()->isFunctionOrMethod()) + continue; + + MissingPrototype = !Prev->getType()->isFunctionProtoType(); + if (FD->getNumParams() == 0) + PossibleZeroParamPrototype = Prev; + break; + } + + return MissingPrototype; +} + +void +Sema::CheckForFunctionRedefinition(FunctionDecl *FD, + const FunctionDecl *EffectiveDefinition) { + // Don't complain if we're in GNU89 mode and the previous definition + // was an extern inline function. + const FunctionDecl *Definition = EffectiveDefinition; + if (!Definition) + if (!FD->isDefined(Definition)) + return; + + if (canRedefineFunction(Definition, getLangOpts())) + return; + + 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(); +} + + +static void RebuildLambdaScopeInfo(CXXMethodDecl *CallOperator, + Sema &S) { + CXXRecordDecl *const LambdaClass = CallOperator->getParent(); + + LambdaScopeInfo *LSI = S.PushLambdaScope(); + LSI->CallOperator = CallOperator; + LSI->Lambda = LambdaClass; + LSI->ReturnType = CallOperator->getResultType(); + const LambdaCaptureDefault LCD = LambdaClass->getLambdaCaptureDefault(); + + if (LCD == LCD_None) + LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_None; + else if (LCD == LCD_ByCopy) + LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByval; + else if (LCD == LCD_ByRef) + LSI->ImpCaptureStyle = CapturingScopeInfo::ImpCap_LambdaByref; + DeclarationNameInfo DNI = CallOperator->getNameInfo(); + + LSI->IntroducerRange = DNI.getCXXOperatorNameRange(); + LSI->Mutable = !CallOperator->isConst(); + + // Add the captures to the LSI so they can be noted as already + // captured within tryCaptureVar. + for (LambdaExpr::capture_iterator C = LambdaClass->captures_begin(), + CEnd = LambdaClass->captures_end(); C != CEnd; ++C) { + if (C->capturesVariable()) { + VarDecl *VD = C->getCapturedVar(); + if (VD->isInitCapture()) + S.CurrentInstantiationScope->InstantiatedLocal(VD, VD); + QualType CaptureType = VD->getType(); + const bool ByRef = C->getCaptureKind() == LCK_ByRef; + LSI->addCapture(VD, /*IsBlock*/false, ByRef, + /*RefersToEnclosingLocal*/true, C->getLocation(), + /*EllipsisLoc*/C->isPackExpansion() + ? C->getEllipsisLoc() : SourceLocation(), + CaptureType, /*Expr*/ 0); + + } else if (C->capturesThis()) { + LSI->addThisCapture(/*Nested*/ false, C->getLocation(), + S.getCurrentThisType(), /*Expr*/ 0); + } + } +} + +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); + // If we are instantiating a generic lambda call operator, push + // a LambdaScopeInfo onto the function stack. But use the information + // that's already been calculated (ActOnLambdaExpr) to prime the current + // LambdaScopeInfo. + // When the template operator is being specialized, the LambdaScopeInfo, + // has to be properly restored so that tryCaptureVariable doesn't try + // and capture any new variables. In addition when calculating potential + // captures during transformation of nested lambdas, it is necessary to + // have the LSI properly restored. + if (isGenericLambdaCallOperatorSpecialization(FD)) { + assert(ActiveTemplateInstantiations.size() && + "There should be an active template instantiation on the stack " + "when instantiating a generic lambda!"); + RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this); + } + else + // 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 (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->isFirstDecl() && 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() && FD->isCanonicalDecl()) + 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))) + diagnoseTypo(Corrected, PDiag(diag::note_function_suggestion), + /*ErrorRecovery*/false); + } + + // 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, + &Context.Idents.get(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, + &Context.Idents.get("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, + &Context.Idents.get("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() && 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, + bool IsFinalSpelledSealed, + 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, IsFinalSpelledSealed)); + + // 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, + 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 (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. + unsigned DiagID = 0; + if (Record->isUnion()) + DiagID = getLangOpts().MicrosoftExt + ? diag::ext_flexible_array_union_ms + : getLangOpts().CPlusPlus + ? diag::ext_flexible_array_union_gnu + : diag::err_flexible_array_union; + else if (Fields.size() == 1) + DiagID = getLangOpts().MicrosoftExt + ? diag::ext_flexible_array_empty_aggregate_ms + : getLangOpts().CPlusPlus + ? diag::ext_flexible_array_empty_aggregate_gnu + : NumNamedMembers < 1 + ? diag::err_flexible_array_empty_aggregate + : 0; + + if (DiagID) + Diag(FD->getLocation(), DiagID) << FD->getDeclName() + << Record->getTagKind(); + // While the layout of types that contain virtual bases is not specified + // by the C++ standard, both the Itanium and Microsoft C++ ABIs place + // virtual bases after the derived members. This would make a flexible + // array member declared at the end of an object not adjacent to the end + // of the type. + if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Record)) + if (RD->getNumVBases() != 0) + Diag(FD->getLocation(), diag::err_flexible_array_virtual_base) + << FD->getDeclName() << Record->getTagKind(); + if (!getLangOpts().C99) + Diag(FD->getLocation(), diag::ext_c99_flexible_array_member) + << FD->getDeclName() << Record->getTagKind(); + + 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 type that can have zero + // size in C. For C this is a language extension, for C++ it may cause + // compatibility problems. + bool CheckForZeroSize; + if (!getLangOpts().CPlusPlus) { + CheckForZeroSize = true; + } else { + // For C++ filter out types that cannot be referenced in C code. + CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); + CheckForZeroSize = + CXXRecord->getLexicalDeclContext()->isExternCContext() && + !CXXRecord->isDependentType() && + CXXRecord->isCLike(); + } + if (CheckForZeroSize) { + 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). They are + // allowed in C++, but warn if its declaration is inside + // extern "C" block. + if (ZeroSize) { + Diag(RecLoc, getLangOpts().CPlusPlus ? + diag::warn_zero_size_struct_union_in_extern_c : + 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 && !getLangOpts().CPlusPlus) { + Diag(RecLoc, IsEmpty ? diag::ext_empty_struct_union : + 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::ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod) { + // FIXME: Should we synthesize an ImportDecl here? + PP.getModuleLoader().makeModuleVisible(Mod, Module::AllVisible, DirectiveLoc, + /*Complain=*/true); +} + +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(); +} |
