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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 | 6708 |
1 files changed, 6708 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..af02099 --- /dev/null +++ b/contrib/llvm/tools/clang/lib/Sema/SemaDecl.cpp @@ -0,0 +1,6708 @@ +//===--- 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 "Sema.h" +#include "SemaInit.h" +#include "Lookup.h" +#include "clang/AST/APValue.h" +#include "clang/AST/ASTConsumer.h" +#include "clang/AST/ASTContext.h" +#include "clang/AST/CXXInheritance.h" +#include "clang/AST/DeclTemplate.h" +#include "clang/AST/ExprCXX.h" +#include "clang/AST/StmtCXX.h" +#include "clang/Parse/DeclSpec.h" +#include "clang/Parse/ParseDiagnostic.h" +#include "clang/Parse/Template.h" +#include "clang/Basic/PartialDiagnostic.h" +#include "clang/Basic/SourceManager.h" +#include "clang/Basic/TargetInfo.h" +// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) +#include "clang/Lex/Preprocessor.h" +#include "clang/Lex/HeaderSearch.h" +#include "llvm/ADT/Triple.h" +#include <algorithm> +#include <cstring> +#include <functional> +using namespace clang; + +/// getDeclName - Return a pretty name for the specified decl if possible, or +/// an empty string if not. This is used for pretty crash reporting. +std::string Sema::getDeclName(DeclPtrTy d) { + Decl *D = d.getAs<Decl>(); + if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) + return DN->getQualifiedNameAsString(); + return ""; +} + +Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { + return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); +} + +/// \brief If the identifier refers to a type name within this scope, +/// return the declaration of that type. +/// +/// This routine performs ordinary name lookup of the identifier II +/// within the given scope, with optional C++ scope specifier SS, to +/// determine whether the name refers to a type. If so, returns an +/// opaque pointer (actually a QualType) corresponding to that +/// type. Otherwise, returns NULL. +/// +/// If name lookup results in an ambiguity, this routine will complain +/// and then return NULL. +Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, + Scope *S, CXXScopeSpec *SS, + bool isClassName, + TypeTy *ObjectTypePtr) { + // Determine where we will perform name lookup. + DeclContext *LookupCtx = 0; + if (ObjectTypePtr) { + QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); + 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) + return 0; + + // We know from the grammar that this name refers to a type, so build a + // DependentNameType node to describe the type. + return CheckTypenameType(ETK_None, + (NestedNameSpecifier *)SS->getScopeRep(), II, + SourceLocation(), SS->getRange(), NameLoc + ).getAsOpaquePtr(); + } + + return 0; + } + + if (!LookupCtx->isDependentContext() && + RequireCompleteDeclContext(*SS, LookupCtx)) + return 0; + } + + // 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: + case LookupResult::FoundOverloaded: + case LookupResult::FoundUnresolvedValue: + Result.suppressDiagnostics(); + return 0; + + 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 0; + } + + // 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 0; + } + + // 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); + + if (SS) + T = getElaboratedType(ETK_None, *SS, T); + + } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { + T = Context.getObjCInterfaceType(IDecl); + } else if (UnresolvedUsingTypenameDecl *UUDecl = + dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { + // FIXME: preserve source structure information. + T = Context.getDependentNameType(ETK_None, + UUDecl->getTargetNestedNameSpecifier(), + &II); + } else { + // If it's not plausibly a type, suppress diagnostics. + Result.suppressDiagnostics(); + return 0; + } + + return T.getAsOpaquePtr(); +} + +/// 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_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()) { + default: return DeclSpec::TST_unspecified; + case TTK_Struct: return DeclSpec::TST_struct; + 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; +} + +bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, + SourceLocation IILoc, + Scope *S, + CXXScopeSpec *SS, + TypeTy *&SuggestedType) { + // We don't have anything to suggest (yet). + SuggestedType = 0; + + // 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. + LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, + NotForRedeclaration); + + if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { + if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { + if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && + !Result->isInvalidDecl()) { + // We found a similarly-named type or interface; suggest that. + if (!SS || !SS->isSet()) + Diag(IILoc, diag::err_unknown_typename_suggest) + << &II << Lookup.getLookupName() + << FixItHint::CreateReplacement(SourceRange(IILoc), + Result->getNameAsString()); + else if (DeclContext *DC = computeDeclContext(*SS, false)) + Diag(IILoc, diag::err_unknown_nested_typename_suggest) + << &II << DC << Lookup.getLookupName() << SS->getRange() + << FixItHint::CreateReplacement(SourceRange(IILoc), + Result->getNameAsString()); + else + llvm_unreachable("could not have corrected a typo here"); + + Diag(Result->getLocation(), diag::note_previous_decl) + << Result->getDeclName(); + + SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); + return true; + } + } else if (Lookup.empty()) { + // We corrected to a keyword. + // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. + Diag(IILoc, diag::err_unknown_typename_suggest) + << &II << Corrected; + return true; + } + } + + if (getLangOptions().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, Name, 0, true, TemplateResult, + MemberOfUnknownSpecialization) == TNK_Type_template) { + TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); + Diag(IILoc, diag::err_template_missing_args) << TplName; + if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { + Diag(TplDecl->getLocation(), diag::note_template_decl_here) + << TplDecl->getTemplateParameters()->getSourceRange(); + } + return true; + } + } + + // FIXME: Should we move the logic that tries to recover from a missing tag + // (struct, union, enum) from Parser::ParseImplicitInt here, instead? + + if (!SS || (!SS->isSet() && !SS->isInvalid())) + Diag(IILoc, diag::err_unknown_typename) << &II; + else if (DeclContext *DC = computeDeclContext(*SS, false)) + Diag(IILoc, diag::err_typename_nested_not_found) + << &II << DC << SS->getRange(); + else if (isDependentScopeSpecifier(*SS)) { + Diag(SS->getRange().getBegin(), diag::err_typename_missing) + << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() + << SourceRange(SS->getRange().getBegin(), IILoc) + << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); + SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); + } else { + assert(SS && SS->isInvalid() && + "Invalid scope specifier has already been diagnosed"); + } + + return true; +} + +// Determines the context to return to after temporarily entering a +// context. This depends in an unnecessarily complicated way on the +// exact ordering of callbacks from the parser. +DeclContext *Sema::getContainingDC(DeclContext *DC) { + + // Functions defined inline within classes aren't parsed until we've + // finished parsing the top-level class, so the top-level class is + // the context we'll need to return to. + if (isa<FunctionDecl>(DC)) { + DC = DC->getLexicalParent(); + + // A function not defined within a class will always return to its + // lexical context. + if (!isa<CXXRecordDecl>(DC)) + return DC; + + // A C++ inline method/friend is parsed *after* the topmost class + // it was declared in is fully parsed ("complete"); the topmost + // class is the context we need to return to. + while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) + DC = RD; + + // Return the declaration context of the topmost class the inline method is + // declared in. + return DC; + } + + if (isa<ObjCMethodDecl>(DC)) + return Context.getTranslationUnitDecl(); + + 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); +} + +/// EnterDeclaratorContext - Used when we must lookup names in the context +/// of a declarator's nested name specifier. +/// +void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { + // C++0x [basic.lookup.unqual]p13: + // A name used in the definition of a static data member of class + // X (after the qualified-id of the static member) is looked up as + // if the name was used in a member function of X. + // C++0x [basic.lookup.unqual]p14: + // If a variable member of a namespace is defined outside of the + // scope of its namespace then any name used in the definition of + // the variable member (after the declarator-id) is looked up as + // if the definition of the variable member occurred in its + // namespace. + // Both of these imply that we should push a scope whose context + // is the semantic context of the declaration. We can't use + // PushDeclContext here because that context is not necessarily + // lexically contained in the current context. Fortunately, + // the containing scope should have the appropriate information. + + assert(!S->getEntity() && "scope already has entity"); + +#ifndef NDEBUG + Scope *Ancestor = S->getParent(); + while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); + assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); +#endif + + CurContext = DC; + S->setEntity(DC); +} + +void Sema::ExitDeclaratorContext(Scope *S) { + assert(S->getEntity() == CurContext && "Context imbalance!"); + + // Switch back to the lexical context. The safety of this is + // enforced by an assert in EnterDeclaratorContext. + Scope *Ancestor = S->getParent(); + while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); + CurContext = (DeclContext*) Ancestor->getEntity(); + + // We don't need to do anything with the scope, which is going to + // disappear. +} + +/// \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.getLangOptions().CPlusPlus) + return true; + + if (Previous.getResultKind() == LookupResult::FoundOverloaded) + return true; + + return (Previous.getResultKind() == LookupResult::Found + && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); +} + +/// Add this decl to the scope shadowed decl chains. +void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { + // Move up the scope chain until we find the nearest enclosing + // non-transparent context. The declaration will be introduced into this + // scope. + while (S->getEntity() && + ((DeclContext *)S->getEntity())->isTransparentContext()) + S = S->getParent(); + + // Add scoped declarations into their context, so that they can be + // found later. Declarations without a context won't be inserted + // into any context. + if (AddToContext) + CurContext->addDecl(D); + + // Out-of-line definitions shouldn't be pushed into scope in C++. + // Out-of-line variable and function definitions shouldn't even in C. + if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && + D->isOutOfLine()) + 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(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { + S->RemoveDecl(DeclPtrTy::make(*I)); + IdResolver.RemoveDecl(*I); + + // Should only need to replace one decl. + break; + } + } + + S->AddDecl(DeclPtrTy::make(D)); + IdResolver.AddDecl(D); +} + +bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { + return IdResolver.isDeclInScope(D, Ctx, Context, S); +} + +static bool isOutOfScopePreviousDeclaration(NamedDecl *, + DeclContext*, + ASTContext&); + +/// Filters out lookup results that don't fall within the given scope +/// as determined by isDeclInScope. +static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, + DeclContext *Ctx, Scope *S, + bool ConsiderLinkage) { + LookupResult::Filter F = R.makeFilter(); + while (F.hasNext()) { + NamedDecl *D = F.next(); + + if (SemaRef.isDeclInScope(D, Ctx, S)) + continue; + + if (ConsiderLinkage && + isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.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(); +} + +static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { + if (D->isInvalidDecl()) + return false; + + if (D->isUsed() || D->hasAttr<UnusedAttr>()) + return false; + + // 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 ValueDecl *VD = dyn_cast<ValueDecl>(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 = dyn_cast<TypedefType>(Ty)) { + 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)) { + // FIXME: Checking for the presence of a user-declared constructor + // isn't completely accurate; we'd prefer to check that the initializer + // has no side effects. + if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) + return false; + } + } + + // TODO: __attribute__((unused)) templates? + } + + return true; +} + +void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { + if (!ShouldDiagnoseUnusedDecl(D)) + return; + + if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) + Diag(D->getLocation(), diag::warn_unused_exception_param) + << D->getDeclName(); + else + Diag(D->getLocation(), diag::warn_unused_variable) + << D->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).getAs<Decl>(); + 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->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) + DiagnoseUnusedDecl(D); + + // Remove this name from our lexical scope. + IdResolver.RemoveDecl(D); + } +} + +/// \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 TypoCorrection 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 TypoCorrection) { + // 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 && TypoCorrection) { + // Perform typo correction at the given location, but only if we + // find an Objective-C class name. + LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); + if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && + (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { + Diag(IdLoc, diag::err_undef_interface_suggest) + << Id << IDecl->getDeclName() + << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); + Diag(IDecl->getLocation(), diag::note_previous_decl) + << IDecl->getDeclName(); + + Id = IDecl->getIdentifier(); + } + } + + return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); +} + +/// getNonFieldDeclScope - Retrieves the innermost scope, starting +/// from S, where a non-field would be declared. This routine copes +/// with the difference between C and C++ scoping rules in structs and +/// unions. For example, the following code is well-formed in C but +/// ill-formed in C++: +/// @code +/// struct S6 { +/// enum { BAR } e; +/// }; +/// +/// void test_S6() { +/// struct S6 a; +/// a.e = BAR; +/// } +/// @endcode +/// For the declaration of BAR, this routine will return a different +/// scope. The scope S will be the scope of the unnamed enumeration +/// within S6. In C++, this routine will return the scope associated +/// with S6, because the enumeration's scope is a transparent +/// context but structures can contain non-field names. In C, this +/// routine will return the translation unit scope, since the +/// enumeration's scope is a transparent context and structures cannot +/// contain non-field names. +Scope *Sema::getNonFieldDeclScope(Scope *S) { + while (((S->getFlags() & Scope::DeclScope) == 0) || + (S->getEntity() && + ((DeclContext *)S->getEntity())->isTransparentContext()) || + (S->isClassScope() && !getLangOptions().CPlusPlus)) + S = S->getParent(); + return S; +} + +void Sema::InitBuiltinVaListType() { + if (!Context.getBuiltinVaListType().isNull()) + return; + + IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); + NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), + LookupOrdinaryName, ForRedeclaration); + TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); + Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); +} + +/// 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) { + Builtin::ID BID = (Builtin::ID)bid; + + if (Context.BuiltinInfo.hasVAListUse(BID)) + InitBuiltinVaListType(); + + 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::err_implicit_decl_requires_stdio) + << Context.BuiltinInfo.GetName(BID); + return 0; + + case ASTContext::GE_Missing_setjmp: + if (ForRedeclaration) + Diag(Loc, diag::err_implicit_decl_requires_setjmp) + << 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) + != Diagnostic::Ignored) + Diag(Loc, diag::note_please_include_header) + << Context.BuiltinInfo.getHeaderName(BID) + << Context.BuiltinInfo.GetName(BID); + } + + FunctionDecl *New = FunctionDecl::Create(Context, + Context.getTranslationUnitDecl(), + Loc, II, R, /*TInfo=*/0, + FunctionDecl::Extern, + FunctionDecl::None, false, + /*hasPrototype=*/true); + New->setImplicit(); + + // Create Decl objects for each parameter, adding them to the + // FunctionDecl. + if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { + llvm::SmallVector<ParmVarDecl*, 16> Params; + for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) + Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, + FT->getArgType(i), /*TInfo=*/0, + VarDecl::None, VarDecl::None, 0)); + New->setParams(Params.data(), Params.size()); + } + + AddKnownFunctionAttributes(New); + + // TUScope is the translation-unit scope to insert this function into. + // FIXME: This is hideous. We need to teach PushOnScopeChains to + // relate Scopes to DeclContexts, and probably eliminate CurContext + // entirely, but we're not there yet. + DeclContext *SavedContext = CurContext; + CurContext = Context.getTranslationUnitDecl(); + PushOnScopeChains(New, TUScope); + CurContext = SavedContext; + return New; +} + +/// MergeTypeDefDecl - 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::MergeTypeDefDecl(TypedefDecl *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 (getLangOptions().ObjC1) { + const IdentifierInfo *TypeID = New->getIdentifier(); + switch (TypeID->getLength()) { + default: break; + case 2: + if (!TypeID->isStr("id")) + break; + Context.ObjCIdRedefinitionType = New->getUnderlyingType(); + // 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.ObjCClassRedefinitionType = 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.ObjCSelRedefinitionType = New->getUnderlyingType(); + // Install the built-in type for 'SEL', ignoring the current definition. + New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); + return; + case 8: + if (!TypeID->isStr("Protocol")) + break; + Context.setObjCProtoType(New->getUnderlyingType()); + 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(); + + // Determine the "old" type we'll use for checking and diagnostics. + QualType OldType; + if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) + OldType = OldTypedef->getUnderlyingType(); + else + OldType = Context.getTypeDeclType(Old); + + // If the typedef types are not identical, reject them in all languages and + // with any extensions enabled. + + if (OldType != New->getUnderlyingType() && + Context.getCanonicalType(OldType) != + Context.getCanonicalType(New->getUnderlyingType())) { + Diag(New->getLocation(), diag::err_redefinition_different_typedef) + << New->getUnderlyingType() << OldType; + if (Old->getLocation().isValid()) + Diag(Old->getLocation(), diag::note_previous_definition); + return New->setInvalidDecl(); + } + + // The types match. Link up the redeclaration chain if the old + // declaration was a typedef. + // FIXME: this is a potential source of wierdness if the type + // spellings don't match exactly. + if (isa<TypedefDecl>(Old)) + New->setPreviousDeclaration(cast<TypedefDecl>(Old)); + + if (getLangOptions().Microsoft) + return; + + if (getLangOptions().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<TypedefDecl >(Old)) + return; + + Diag(New->getLocation(), diag::err_redefinition) + << New->getDeclName(); + Diag(Old->getLocation(), diag::note_previous_definition); + return New->setInvalidDecl(); + } + + // 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 *decl, const Attr *target) { + for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) + if (attr->getKind() == target->getKind()) + return true; + + return false; +} + +/// MergeAttributes - append attributes from the Old decl to the New one. +static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { + for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { + if (!DeclHasAttr(New, attr) && attr->isMerged()) { + Attr *NewAttr = attr->clone(C); + NewAttr->setInherited(true); + New->addAttr(NewAttr); + } + } +} + +/// 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->isCopyConstructor()) + return Sema::CXXCopyConstructor; + + return Sema::CXXConstructor; + } + + if (isa<CXXDestructorDecl>(MD)) + return Sema::CXXDestructor; + + assert(MD->isCopyAssignment() && "Must have copy assignment operator"); + return Sema::CXXCopyAssignment; +} + +/// 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 (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && + FD->isInlineSpecified() && + FD->getStorageClass() == FunctionDecl::Extern); +} + +/// 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) { + // 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)) { + 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; + } + + // Determine whether the previous declaration was a definition, + // implicit declaration, or a declaration. + diag::kind PrevDiag; + if (Old->isThisDeclarationADefinition()) + PrevDiag = diag::note_previous_definition; + else if (Old->isImplicit()) + PrevDiag = diag::note_previous_implicit_declaration; + else + PrevDiag = diag::note_previous_declaration; + + QualType OldQType = Context.getCanonicalType(Old->getType()); + QualType NewQType = Context.getCanonicalType(New->getType()); + + // Don't complain about this if we're in GNU89 mode and the old function + // is an extern inline function. + if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && + New->getStorageClass() == FunctionDecl::Static && + Old->getStorageClass() != FunctionDecl::Static && + !canRedefineFunction(Old, getLangOptions())) { + Diag(New->getLocation(), diag::err_static_non_static) + << New; + Diag(Old->getLocation(), PrevDiag); + return true; + } + + // If a function is first declared with a calling convention, but is + // later declared or defined without one, the second decl assumes the + // calling convention of the first. + // + // For the new decl, we have to look at the NON-canonical type to tell the + // difference between a function that really doesn't have a calling + // convention and one that is declared cdecl. That's because in + // canonicalization (see ASTContext.cpp), cdecl is canonicalized away + // because it is the default calling convention. + // + // Note also that we DO NOT return at this point, because we still have + // other tests to run. + const FunctionType *OldType = OldQType->getAs<FunctionType>(); + const FunctionType *NewType = New->getType()->getAs<FunctionType>(); + const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); + const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); + if (OldTypeInfo.getCC() != CC_Default && + NewTypeInfo.getCC() == CC_Default) { + NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); + New->setType(NewQType); + NewQType = Context.getCanonicalType(NewQType); + } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), + NewTypeInfo.getCC())) { + // Calling conventions really aren't compatible, so complain. + Diag(New->getLocation(), diag::err_cconv_change) + << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) + << (OldTypeInfo.getCC() == CC_Default) + << (OldTypeInfo.getCC() == CC_Default ? "" : + FunctionType::getNameForCallConv(OldTypeInfo.getCC())); + Diag(Old->getLocation(), diag::note_previous_declaration); + return true; + } + + // FIXME: diagnose the other way around? + if (OldType->getNoReturnAttr() && + !NewType->getNoReturnAttr()) { + NewQType = Context.getNoReturnType(NewQType); + New->setType(NewQType); + assert(NewQType.isCanonical()); + } + + if (getLangOptions().CPlusPlus) { + // (C++98 13.1p2): + // Certain function declarations cannot be overloaded: + // -- Function declarations that differ only in the return type + // cannot be overloaded. + QualType OldReturnType + = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); + QualType NewReturnType + = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); + QualType ResQT; + if (OldReturnType != NewReturnType) { + if (NewReturnType->isObjCObjectPointerType() + && OldReturnType->isObjCObjectPointerType()) + ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); + if (ResQT.isNull()) { + Diag(New->getLocation(), diag::err_ovl_diff_return_type); + Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); + return true; + } + else + NewQType = ResQT; + } + + const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); + CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); + if (OldMethod && NewMethod) { + // Preserve triviality. + NewMethod->setTrivial(OldMethod->isTrivial()); + + bool isFriend = NewMethod->getFriendObjectKind(); + + if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { + // -- 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. + 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); + 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; + } + } + } + + // (C++98 8.3.5p3): + // All declarations for a function shall agree exactly in both the + // return type and the parameter-type-list. + // attributes should be ignored when comparing. + if (Context.getNoReturnType(OldQType, false) == + Context.getNoReturnType(NewQType, false)) + return MergeCompatibleFunctionDecls(New, Old); + + // 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 (!getLangOptions().CPlusPlus && + Context.typesAreCompatible(OldQType, NewQType)) { + const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); + const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); + const FunctionProtoType *OldProto = 0; + if (isa<FunctionNoProtoType>(NewFuncType) && + (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { + // The old declaration provided a function prototype, but the + // new declaration does not. Merge in the prototype. + assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); + llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), + OldProto->arg_type_end()); + NewQType = Context.getFunctionType(NewFuncType->getResultType(), + ParamTypes.data(), ParamTypes.size(), + OldProto->isVariadic(), + OldProto->getTypeQuals(), + false, false, 0, 0, + OldProto->getExtInfo()); + New->setType(NewQType); + New->setHasInheritedPrototype(); + + // Synthesize a parameter for each argument type. + llvm::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(), 0, + *ParamType, /*TInfo=*/0, + VarDecl::None, VarDecl::None, + 0); + Param->setImplicit(); + Params.push_back(Param); + } + + New->setParams(Params.data(), Params.size()); + } + + return MergeCompatibleFunctionDecls(New, Old); + } + + // 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 (!getLangOptions().CPlusPlus && + Old->hasPrototype() && !New->hasPrototype() && + New->getType()->getAs<FunctionProtoType>() && + Old->getNumParams() == New->getNumParams()) { + llvm::SmallVector<QualType, 16> ArgTypes; + llvm::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())) { + 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(); + Diag(Warnings[Warn].OldParm->getLocation(), + diag::note_previous_declaration); + } + + New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], + ArgTypes.size(), + OldProto->isVariadic(), 0, + false, false, 0, 0, + OldProto->getExtInfo())); + return MergeCompatibleFunctionDecls(New, Old); + } + + // Fall through to diagnose conflicting types. + } + + // A function that has already been declared has been redeclared or defined + // with a different type- show appropriate diagnostic + if (unsigned BuiltinID = Old->getBuiltinID()) { + // The user has declared a builtin function with an incompatible + // signature. + if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { + // The function the user is redeclaring is a library-defined + // function like 'malloc' or 'printf'. Warn about the + // redeclaration, then pretend that we don't know about this + // library built-in. + Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; + Diag(Old->getLocation(), diag::note_previous_builtin_declaration) + << Old << Old->getType(); + New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); + Old->setInvalidDecl(); + return false; + } + + PrevDiag = diag::note_previous_builtin_declaration; + } + + Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); + Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); + return true; +} + +/// \brief Completes the merge of two function declarations that are +/// known to be compatible. +/// +/// This routine handles the merging of attributes and other +/// properties of function declarations form the old declaration to +/// the new declaration, once we know that New is in fact a +/// redeclaration of Old. +/// +/// \returns false +bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { + // Merge the attributes + MergeAttributes(New, Old, Context); + + // Merge the storage class. + if (Old->getStorageClass() != FunctionDecl::Extern && + Old->getStorageClass() != FunctionDecl::None) + New->setStorageClass(Old->getStorageClass()); + + // Merge "pure" flag. + if (Old->isPure()) + New->setPure(); + + // Merge the "deleted" flag. + if (Old->isDeleted()) + New->setDeleted(); + + if (getLangOptions().CPlusPlus) + return MergeCXXFunctionDecl(New, Old); + + return false; +} + +/// 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. + VarDecl *Old = 0; + if (!Previous.isSingleResult() || + !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { + Diag(New->getLocation(), diag::err_redefinition_different_kind) + << New->getDeclName(); + Diag(Previous.getRepresentativeDecl()->getLocation(), + diag::note_previous_definition); + return New->setInvalidDecl(); + } + + MergeAttributes(New, Old, Context); + + // Merge the types + QualType MergedT; + if (getLangOptions().CPlusPlus) { + if (Context.hasSameType(New->getType(), Old->getType())) + MergedT = New->getType(); + // 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()) { + CanQual<ArrayType> OldArray + = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); + CanQual<ArrayType> NewArray + = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); + if (OldArray->getElementType() == NewArray->getElementType()) + MergedT = New->getType(); + } else if (Old->getType()->isArrayType() && + New->getType()->isIncompleteArrayType()) { + CanQual<ArrayType> OldArray + = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); + CanQual<ArrayType> NewArray + = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); + if (OldArray->getElementType() == NewArray->getElementType()) + MergedT = Old->getType(); + } else if (New->getType()->isObjCObjectPointerType() + && Old->getType()->isObjCObjectPointerType()) { + MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); + } + } else { + MergedT = Context.mergeTypes(New->getType(), Old->getType()); + } + if (MergedT.isNull()) { + Diag(New->getLocation(), diag::err_redefinition_different_type) + << New->getDeclName(); + Diag(Old->getLocation(), diag::note_previous_definition); + return New->setInvalidDecl(); + } + New->setType(MergedT); + + // C99 6.2.2p4: Check if we have a static decl followed by a non-static. + if (New->getStorageClass() == VarDecl::Static && + (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { + 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->getStorageClass() != VarDecl::Static && + Old->getStorageClass() == VarDecl::Static) { + Diag(New->getLocation(), diag::err_non_static_static) << 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->isThreadSpecified() && !Old->isThreadSpecified()) { + Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); + Diag(Old->getLocation(), diag::note_previous_definition); + } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { + Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); + Diag(Old->getLocation(), diag::note_previous_definition); + } + + // C++ doesn't have tentative definitions, so go right ahead and check here. + const VarDecl *Def; + if (getLangOptions().CPlusPlus && + New->isThisDeclarationADefinition() == VarDecl::Definition && + (Def = Old->getDefinition())) { + Diag(New->getLocation(), diag::err_redefinition) + << New->getDeclName(); + Diag(Def->getLocation(), diag::note_previous_definition); + New->setInvalidDecl(); + return; + } + + // Keep a chain of previous declarations. + New->setPreviousDeclaration(Old); + + // Inherit access appropriately. + New->setAccess(Old->getAccess()); +} + +/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with +/// no declarator (e.g. "struct foo;") is parsed. +Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, + DeclSpec &DS) { + // FIXME: Error on auto/register at file scope + // FIXME: Error on inline/virtual/explicit + // FIXME: Warn on useless __thread + // FIXME: Warn on useless const/volatile + // FIXME: Warn on useless static/extern/typedef/private_extern/mutable + // FIXME: Warn on useless attributes + Decl *TagD = 0; + TagDecl *Tag = 0; + if (DS.getTypeSpecType() == DeclSpec::TST_class || + DS.getTypeSpecType() == DeclSpec::TST_struct || + DS.getTypeSpecType() == DeclSpec::TST_union || + DS.getTypeSpecType() == DeclSpec::TST_enum) { + TagD = static_cast<Decl *>(DS.getTypeRep()); + + if (!TagD) // We probably had an error + return DeclPtrTy(); + + // Note that the above type specs guarantee that the + // type rep is a Decl, whereas in many of the others + // it's a Type. + Tag = dyn_cast<TagDecl>(TagD); + } + + 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.isFriendSpecified()) { + // If we're dealing with a class template decl, assume that the + // template routines are handling it. + if (TagD && isa<ClassTemplateDecl>(TagD)) + return DeclPtrTy(); + return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); + } + + if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { + // If there are attributes in the DeclSpec, apply them to the record. + if (const AttributeList *AL = DS.getAttributes()) + ProcessDeclAttributeList(S, Record, AL); + + if (!Record->getDeclName() && Record->isDefinition() && + DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { + if (getLangOptions().CPlusPlus || + Record->getDeclContext()->isRecord()) + return BuildAnonymousStructOrUnion(S, DS, AS, Record); + + Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) + << DS.getSourceRange(); + } + + // Microsoft allows unnamed struct/union fields. Don't complain + // about them. + // FIXME: Should we support Microsoft's extensions in this area? + if (Record->getDeclName() && getLangOptions().Microsoft) + return DeclPtrTy::make(Tag); + } + + if (!DS.isMissingDeclaratorOk() && + DS.getTypeSpecType() != DeclSpec::TST_error) { + // Warn about typedefs of enums without names, since this is an + // extension in both Microsoft an GNU. + if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && + Tag && isa<EnumDecl>(Tag)) { + Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) + << DS.getSourceRange(); + return DeclPtrTy::make(Tag); + } + + Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) + << DS.getSourceRange(); + } + + return DeclPtrTy::make(Tag); +} + +/// 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(); + if (PrevDecl && Owner->isRecord()) { + RecordDecl *Record = cast<RecordDecl>(Owner); + if (!SemaRef.isDeclInScope(PrevDecl, Record, 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) { + unsigned diagKind + = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl + : diag::err_anonymous_struct_member_redecl; + + bool Invalid = false; + for (RecordDecl::field_iterator F = AnonRecord->field_begin(), + FEnd = AnonRecord->field_end(); + F != FEnd; ++F) { + if ((*F)->getDeclName()) { + if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), + (*F)->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. + Owner->makeDeclVisibleInContext(*F); + S->AddDecl(Sema::DeclPtrTy::make(*F)); + SemaRef.IdResolver.AddDecl(*F); + + // That includes picking up the appropriate access specifier. + if (AS != AS_none) (*F)->setAccess(AS); + } + } else if (const RecordType *InnerRecordType + = (*F)->getType()->getAs<RecordType>()) { + RecordDecl *InnerRecord = InnerRecordType->getDecl(); + if (InnerRecord->isAnonymousStructOrUnion()) + Invalid = Invalid || + InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, + InnerRecord, AS); + } + } + + 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 VarDecl::None. +/// If the input declaration context is a linkage specification +/// with no braces, then Extern is mapped to None. +static VarDecl::StorageClass +StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec, + DeclContext *DC) { + switch (StorageClassSpec) { + case DeclSpec::SCS_unspecified: return VarDecl::None; + case DeclSpec::SCS_extern: + // If the current context is a C++ linkage specification + // having no braces, then the keyword "extern" is properly part + // of the linkage specification itself, rather than being + // the written storage class specifier. + return (DC && isa<LinkageSpecDecl>(DC) && + !cast<LinkageSpecDecl>(DC)->hasBraces()) + ? VarDecl::None : VarDecl::Extern; + case DeclSpec::SCS_static: return VarDecl::Static; + case DeclSpec::SCS_auto: return VarDecl::Auto; + case DeclSpec::SCS_register: return VarDecl::Register; + case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; + // Illegal SCSs map to None: error reporting is up to the caller. + case DeclSpec::SCS_mutable: // Fall through. + case DeclSpec::SCS_typedef: return VarDecl::None; + } + llvm_unreachable("unknown storage class specifier"); +} + +/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to +/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: +/// illegal input values are mapped to FunctionDecl::None. +/// If the input declaration context is a linkage specification +/// with no braces, then Extern is mapped to None. +static FunctionDecl::StorageClass +StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec, + DeclContext *DC) { + switch (StorageClassSpec) { + case DeclSpec::SCS_unspecified: return FunctionDecl::None; + case DeclSpec::SCS_extern: + // If the current context is a C++ linkage specification + // having no braces, then the keyword "extern" is properly part + // of the linkage specification itself, rather than being + // the written storage class specifier. + return (DC && isa<LinkageSpecDecl>(DC) && + !cast<LinkageSpecDecl>(DC)->hasBraces()) + ? FunctionDecl::None : FunctionDecl::Extern; + case DeclSpec::SCS_static: return FunctionDecl::Static; + case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; + // Illegal SCSs map to None: error reporting is up to the caller. + case DeclSpec::SCS_auto: // Fall through. + case DeclSpec::SCS_mutable: // Fall through. + case DeclSpec::SCS_register: // Fall through. + case DeclSpec::SCS_typedef: return FunctionDecl::None; + } + llvm_unreachable("unknown storage class specifier"); +} + +/// ActOnAnonymousStructOrUnion - Handle the declaration of an +/// anonymous structure or union. Anonymous unions are a C++ feature +/// (C++ [class.union]) and a GNU C extension; anonymous structures +/// are a GNU C and GNU C++ extension. +Sema::DeclPtrTy 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() && !getLangOptions().CPlusPlus) + Diag(Record->getLocation(), diag::ext_anonymous_union); + else if (!Record->isUnion()) + Diag(Record->getLocation(), diag::ext_anonymous_struct); + + // C and C++ require different kinds of checks for anonymous + // structs/unions. + bool Invalid = false; + if (getLangOptions().CPlusPlus) { + const char* PrevSpec = 0; + unsigned DiagID; + // C++ [class.union]p3: + // 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); + Invalid = true; + + // Recover by adding 'static'. + DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), + PrevSpec, DiagID); + } + // C++ [class.union]p3: + // 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); + Invalid = true; + + // Recover by removing the storage specifier. + DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), + PrevSpec, DiagID); + } + + // 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; + } + } 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()) { + // This is a nested type declaration. + Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) + << (int)Record->isUnion(); + Invalid = true; + } + } 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; + Diag((*Mem)->getLocation(), DK) + << (int)Record->isUnion(); + Invalid = true; + } + } + } + + if (!Record->isUnion() && !Owner->isRecord()) { + Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) + << (int)getLangOptions().CPlusPlus; + Invalid = true; + } + + // Mock up a declarator. + Declarator Dc(DS, Declarator::TypeNameContext); + TypeSourceInfo *TInfo = 0; + GetTypeForDeclarator(Dc, S, &TInfo); + 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, Record->getLocation(), + /*IdentifierInfo=*/0, + Context.getTypeDeclType(Record), + TInfo, + /*BitWidth=*/0, /*Mutable=*/false); + Anon->setAccess(AS); + if (getLangOptions().CPlusPlus) { + FieldCollector->Add(cast<FieldDecl>(Anon)); + if (!cast<CXXRecordDecl>(Record)->isEmpty()) + cast<CXXRecordDecl>(OwningClass)->setEmpty(false); + } + } else { + DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); + assert(SCSpec != DeclSpec::SCS_typedef && + "Parser allowed 'typedef' as storage class VarDecl."); + VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); + 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 = VarDecl::None; + } + SCSpec = DS.getStorageClassSpecAsWritten(); + VarDecl::StorageClass SCAsWritten + = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); + + Anon = VarDecl::Create(Context, Owner, Record->getLocation(), + /*IdentifierInfo=*/0, + Context.getTypeDeclType(Record), + TInfo, SC, SCAsWritten); + } + 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. + if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) + 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 DeclPtrTy::make(Anon); +} + + +/// GetNameForDeclarator - Determine the full declaration name for the +/// given Declarator. +DeclarationName Sema::GetNameForDeclarator(Declarator &D) { + return GetNameFromUnqualifiedId(D.getName()); +} + +/// \brief Retrieves the canonicalized name from a parsed unqualified-id. +DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { + switch (Name.getKind()) { + case UnqualifiedId::IK_Identifier: + return DeclarationName(Name.Identifier); + + case UnqualifiedId::IK_OperatorFunctionId: + return Context.DeclarationNames.getCXXOperatorName( + Name.OperatorFunctionId.Operator); + + case UnqualifiedId::IK_LiteralOperatorId: + return Context.DeclarationNames.getCXXLiteralOperatorName( + Name.Identifier); + + case UnqualifiedId::IK_ConversionFunctionId: { + QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); + if (Ty.isNull()) + return DeclarationName(); + + return Context.DeclarationNames.getCXXConversionFunctionName( + Context.getCanonicalType(Ty)); + } + + case UnqualifiedId::IK_ConstructorName: { + QualType Ty = GetTypeFromParser(Name.ConstructorName); + if (Ty.isNull()) + return DeclarationName(); + + return Context.DeclarationNames.getCXXConstructorName( + Context.getCanonicalType(Ty)); + } + + 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 DeclarationName(); + + // 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. + + return Context.DeclarationNames.getCXXConstructorName( + Context.getCanonicalType(CurClassType)); + } + + case UnqualifiedId::IK_DestructorName: { + QualType Ty = GetTypeFromParser(Name.DestructorName); + if (Ty.isNull()) + return DeclarationName(); + + return Context.DeclarationNames.getCXXDestructorName( + Context.getCanonicalType(Ty)); + } + + case UnqualifiedId::IK_TemplateId: { + TemplateName TName + = TemplateName::getFromVoidPointer(Name.TemplateId->Template); + return Context.getNameForTemplate(TName); + } + } + + assert(false && "Unknown name kind"); + return DeclarationName(); +} + +/// isNearlyMatchingFunction - Determine whether the C++ functions +/// Declaration and Definition are "nearly" matching. 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. +static bool isNearlyMatchingFunction(ASTContext &Context, + FunctionDecl *Declaration, + FunctionDecl *Definition) { + 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(); + + if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), + DefParamTy.getNonReferenceType())) + 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_typeofExpr: + case DeclSpec::TST_decltype: { + // Grab the type from the parser. + TypeSourceInfo *TSI = 0; + QualType T = S.GetTypeFromParser(DS.getTypeRep(), &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. + QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); + DS.UpdateTypeRep(LocType.getAsOpaquePtr()); + 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; +} + +Sema::DeclPtrTy +Sema::HandleDeclarator(Scope *S, Declarator &D, + MultiTemplateParamsArg TemplateParamLists, + bool IsFunctionDefinition) { + DeclarationName Name = GetNameForDeclarator(D); + + // 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().getSourceRange().getBegin(), + diag::err_declarator_need_ident) + << D.getDeclSpec().getSourceRange() << D.getSourceRange(); + return DeclPtrTy(); + } + + // 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()) { + bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); + DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); + if (!DC) { + // If we could not compute the declaration context, it's because the + // declaration context is dependent but does not refer to a class, + // class template, or class template partial specialization. Complain + // and return early, to avoid the coming semantic disaster. + Diag(D.getIdentifierLoc(), + diag::err_template_qualified_declarator_no_match) + << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() + << D.getCXXScopeSpec().getRange(); + return DeclPtrTy(); + } + + bool IsDependentContext = DC->isDependentContext(); + + if (!IsDependentContext && + RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) + return DeclPtrTy(); + + if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { + Diag(D.getIdentifierLoc(), + diag::err_member_def_undefined_record) + << Name << DC << D.getCXXScopeSpec().getRange(); + 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(); + } + } + + NamedDecl *New; + + TypeSourceInfo *TInfo = 0; + QualType R = GetTypeForDeclarator(D, S, &TInfo); + + LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, + ForRedeclaration); + + // See if this is a redefinition of a variable in the same scope. + if (!D.getCXXScopeSpec().isSet()) { + bool IsLinkageLookup = false; + + // If the declaration we're planning to build will be a function + // or object with linkage, then look for another declaration with + // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). + if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) + /* Do nothing*/; + else if (R->isFunctionType()) { + if (CurContext->isFunctionOrMethod() || + D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) + IsLinkageLookup = true; + } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) + IsLinkageLookup = true; + else if (CurContext->getLookupContext()->isTranslationUnit() && + D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) + IsLinkageLookup = true; + + if (IsLinkageLookup) + Previous.clear(LookupRedeclarationWithLinkage); + + LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); + } else { // Something like "int foo::x;" + LookupQualifiedName(Previous, DC); + + // Don't consider using declarations as previous declarations for + // out-of-line members. + RemoveUsingDecls(Previous); + + // C++ 7.3.1.2p2: + // Members (including explicit specializations of templates) of a named + // namespace can also be defined outside that namespace by explicit + // qualification of the name being defined, provided that the entity being + // defined was already declared in the namespace and the definition appears + // after the point of declaration in a namespace that encloses the + // declarations namespace. + // + // Note that we only check the context at this point. We don't yet + // have enough information to make sure that PrevDecl is actually + // 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, PrevDecl will point to the overload set + // containing the two f's declared in X, but neither of them + // matches. + + // First check whether we named the global scope. + if (isa<TranslationUnitDecl>(DC)) { + Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) + << Name << D.getCXXScopeSpec().getRange(); + } else { + DeclContext *Cur = CurContext; + while (isa<LinkageSpecDecl>(Cur)) + Cur = Cur->getParent(); + if (!Cur->Encloses(DC)) { + // The qualifying scope doesn't enclose the original declaration. + // Emit diagnostic based on current scope. + SourceLocation L = D.getIdentifierLoc(); + SourceRange R = D.getCXXScopeSpec().getRange(); + if (isa<FunctionDecl>(Cur)) + Diag(L, diag::err_invalid_declarator_in_function) << Name << R; + else + Diag(L, diag::err_invalid_declarator_scope) + << Name << cast<NamedDecl>(DC) << R; + D.setInvalidType(); + } + } + } + + if (Previous.isSingleResult() && + Previous.getFoundDecl()->isTemplateParameter()) { + // Maybe we will complain about the shadowed template parameter. + if (!D.isInvalidType()) + if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), + Previous.getFoundDecl())) + D.setInvalidType(); + + // 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(); + + bool Redeclaration = false; + if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { + if (TemplateParamLists.size()) { + Diag(D.getIdentifierLoc(), diag::err_template_typedef); + return DeclPtrTy(); + } + + New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); + } else if (R->isFunctionType()) { + New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, + move(TemplateParamLists), + IsFunctionDefinition, Redeclaration); + } else { + New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, + move(TemplateParamLists), + Redeclaration); + } + + if (New == 0) + return DeclPtrTy(); + + // If this has an identifier and is not an invalid redeclaration or + // function template specialization, add it to the scope stack. + if (Name && !(Redeclaration && New->isInvalidDecl())) + PushOnScopeChains(New, S); + + return DeclPtrTy::make(New); +} + +/// TryToFixInvalidVariablyModifiedType - 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) { + // 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; + + 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); + if (FixedType.isNull()) return FixedType; + FixedType = Context.getPointerType(FixedType); + return Qs.apply(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(); + + Expr::EvalResult EvalResult; + if (!VLATy->getSizeExpr() || + !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || + !EvalResult.Val.isInt()) + return QualType(); + + llvm::APSInt &Res = EvalResult.Val.getInt(); + if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { + // TODO: preserve the size expression in declarator info + return Context.getConstantArrayType(VLATy->getElementType(), + Res, ArrayType::Normal, 0); + } + + SizeIsNegative = true; + return QualType(); +} + +/// \brief Register the given locally-scoped external C declaration so +/// that it can be found later for redeclarations +void +Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, + const LookupResult &Previous, + Scope *S) { + assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && + "Decl is not a locally-scoped decl!"); + // Note that we have a locally-scoped external with this name. + LocallyScopedExternalDecls[ND->getDeclName()] = ND; + + if (!Previous.isSingleResult()) + return; + + NamedDecl *PrevDecl = Previous.getFoundDecl(); + + // If there was a previous declaration of this variable, it may be + // in our identifier chain. Update the identifier chain with the new + // declaration. + if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { + // The previous declaration was found on the identifer resolver + // chain, so remove it from its scope. + while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) + S = S->getParent(); + + if (S) + S->RemoveDecl(DeclPtrTy::make(PrevDecl)); + } +} + +/// \brief Diagnose function specifiers on a declaration of an identifier that +/// does not identify a function. +void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { + // FIXME: We should probably indicate the identifier in question to avoid + // confusion for constructs like "inline int a(), b;" + if (D.getDeclSpec().isInlineSpecified()) + Diag(D.getDeclSpec().getInlineSpecLoc(), + diag::err_inline_non_function); + + if (D.getDeclSpec().isVirtualSpecified()) + Diag(D.getDeclSpec().getVirtualSpecLoc(), + diag::err_virtual_non_function); + + if (D.getDeclSpec().isExplicitSpecified()) + Diag(D.getDeclSpec().getExplicitSpecLoc(), + diag::err_explicit_non_function); +} + +NamedDecl* +Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, + QualType R, TypeSourceInfo *TInfo, + LookupResult &Previous, bool &Redeclaration) { + // 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(); + } + + if (getLangOptions().CPlusPlus) { + // Check that there are no default arguments (C++ only). + CheckExtraCXXDefaultArguments(D); + } + + DiagnoseFunctionSpecifiers(D); + + if (D.getDeclSpec().isThreadSpecified()) + Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); + + TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); + if (!NewTD) return 0; + + // Handle attributes prior to checking for duplicates in MergeVarDecl + ProcessDeclAttributes(S, NewTD, D); + + // Merge the decl with the existing one if appropriate. If the decl is + // in an outer scope, it isn't the same thing. + FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); + if (!Previous.empty()) { + Redeclaration = true; + MergeTypeDefDecl(NewTD, Previous); + } + + // C99 6.7.7p2: If a typedef name specifies a variably modified type + // then it shall have block scope. + QualType T = NewTD->getUnderlyingType(); + if (T->isVariablyModifiedType()) { + FunctionNeedsScopeChecking() = true; + + if (S->getFnParent() == 0) { + bool SizeIsNegative; + QualType FixedTy = + TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); + if (!FixedTy.isNull()) { + Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); + NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); + } else { + if (SizeIsNegative) + Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); + else if (T->isVariableArrayType()) + Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); + else + Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); + NewTD->setInvalidDecl(); + } + } + } + + // If this is the C FILE type, notify the AST context. + if (IdentifierInfo *II = NewTD->getIdentifier()) + if (!NewTD->isInvalidDecl() && + NewTD->getDeclContext()->getLookupContext()->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); + } + + 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 0; + + if (!PrevDecl->hasLinkage()) + return false; + + if (Context.getLangOptions().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->getLookupContext(); + if (!OuterContext->isFunctionOrMethod()) + // This rule only applies to block-scope declarations. + return false; + else { + DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); + if (PrevOuterContext->isRecord()) + // We found a member function: ignore it. + return false; + else { + // Find the innermost enclosing namespace for the new and + // previous declarations. + while (!OuterContext->isFileContext()) + OuterContext = OuterContext->getParent(); + while (!PrevOuterContext->isFileContext()) + PrevOuterContext = PrevOuterContext->getParent(); + + // The previous declaration is in a different namespace, so it + // isn't the same function. + if (OuterContext->getPrimaryContext() != + PrevOuterContext->getPrimaryContext()) + return false; + } + } + } + + return true; +} + +static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { + CXXScopeSpec &SS = D.getCXXScopeSpec(); + if (!SS.isSet()) return; + DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), + SS.getRange()); +} + +NamedDecl* +Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, + QualType R, TypeSourceInfo *TInfo, + LookupResult &Previous, + MultiTemplateParamsArg TemplateParamLists, + bool &Redeclaration) { + DeclarationName Name = GetNameForDeclarator(D); + + // Check that there are no default arguments (C++ only). + if (getLangOptions().CPlusPlus) + CheckExtraCXXDefaultArguments(D); + + DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); + assert(SCSpec != DeclSpec::SCS_typedef && + "Parser allowed 'typedef' as storage class VarDecl."); + VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); + 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 = VarDecl::None; + } + SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); + VarDecl::StorageClass SCAsWritten + = StorageClassSpecToVarDeclStorageClass(SCSpec, DC); + + IdentifierInfo *II = Name.getAsIdentifierInfo(); + if (!II) { + Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) + << Name.getAsString(); + return 0; + } + + DiagnoseFunctionSpecifiers(D); + + 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 == VarDecl::Auto || SC == VarDecl::Register) { + + // If this is a register variable with an asm label specified, then this + // is a GNU extension. + if (SC == VarDecl::Register && D.getAsmLabel()) + Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); + else + Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); + D.setInvalidType(); + } + } + if (DC->isRecord() && !CurContext->isRecord()) { + // This is an out-of-line definition of a static data member. + if (SC == VarDecl::Static) { + Diag(D.getDeclSpec().getStorageClassSpecLoc(), + diag::err_static_out_of_line) + << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); + } else if (SC == VarDecl::None) + SC = VarDecl::Static; + } + if (SC == VarDecl::Static) { + 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(); + } + } + + // Match up the template parameter lists with the scope specifier, then + // determine whether we have a template or a template specialization. + bool isExplicitSpecialization = false; + if (TemplateParameterList *TemplateParams + = MatchTemplateParametersToScopeSpecifier( + D.getDeclSpec().getSourceRange().getBegin(), + D.getCXXScopeSpec(), + (TemplateParameterList**)TemplateParamLists.get(), + TemplateParamLists.size(), + /*never a friend*/ false, + isExplicitSpecialization)) { + if (TemplateParams->size() > 0) { + // There is no such thing as a variable template. + Diag(D.getIdentifierLoc(), diag::err_template_variable) + << II + << SourceRange(TemplateParams->getTemplateLoc(), + TemplateParams->getRAngleLoc()); + return 0; + } else { + // 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()); + + isExplicitSpecialization = true; + } + } + + VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), + II, R, TInfo, SC, SCAsWritten); + + if (D.isInvalidType()) + NewVD->setInvalidDecl(); + + SetNestedNameSpecifier(NewVD, D); + + if (D.getDeclSpec().isThreadSpecified()) { + if (NewVD->hasLocalStorage()) + Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); + else if (!Context.Target.isTLSSupported()) + Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); + else + NewVD->setThreadSpecified(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); + + // Handle attributes prior to checking for duplicates in MergeVarDecl + ProcessDeclAttributes(S, NewVD, D); + + // 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); + NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); + } + + // 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(*this, Previous, DC, S, NewVD->hasLinkage()); + + // 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(); + } + + CheckVariableDeclaration(NewVD, Previous, Redeclaration); + + // This is an explicit specialization of a static data member. Check it. + if (isExplicitSpecialization && !NewVD->isInvalidDecl() && + CheckMemberSpecialization(NewVD, Previous)) + NewVD->setInvalidDecl(); + + // attributes declared post-definition are currently ignored + if (Previous.isSingleResult()) { + VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); + if (Def && (Def = Def->getDefinition()) && + Def != NewVD && D.hasAttributes()) { + Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); + Diag(Def->getLocation(), diag::note_previous_definition); + } + } + + // If this is a locally-scoped extern C variable, update the map of + // such variables. + if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && + !NewVD->isInvalidDecl()) + RegisterLocallyScopedExternCDecl(NewVD, Previous, S); + + 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) == Diagnostic::Ignored) + return; + + // Don't diagnose declarations at file scope. The scope might not + // have a DeclContext if (e.g.) we're parsing a function prototype. + DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); + if (NewDC && NewDC->isFileContext()) + return; + + // 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; + + 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) { + LookupResult R(*this, D->getDeclName(), D->getLocation(), + Sema::LookupOrdinaryName, Sema::ForRedeclaration); + LookupName(R, S); + CheckShadow(S, D, R); +} + +/// \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. +void Sema::CheckVariableDeclaration(VarDecl *NewVD, + LookupResult &Previous, + bool &Redeclaration) { + // If the decl is already known invalid, don't check it. + if (NewVD->isInvalidDecl()) + return; + + QualType T = NewVD->getType(); + + if (T->isObjCObjectType()) { + Diag(NewVD->getLocation(), diag::err_statically_allocated_object); + return NewVD->setInvalidDecl(); + } + + // 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); + return NewVD->setInvalidDecl(); + } + + if (NewVD->hasLocalStorage() && T.isObjCGCWeak() + && !NewVD->hasAttr<BlocksAttr>()) + Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); + + bool isVM = T->isVariablyModifiedType(); + if (isVM || NewVD->hasAttr<CleanupAttr>() || + NewVD->hasAttr<BlocksAttr>() || + // FIXME: We need to diagnose jumps passed initialized variables in C++. + // However, this turns on the scope checker for everything with a variable + // which may impact compile time. See if we can find a better solution + // to this, perhaps only checking functions that contain gotos in C++? + (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) + FunctionNeedsScopeChecking() = true; + + if ((isVM && NewVD->hasLinkage()) || + (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { + bool SizeIsNegative; + QualType FixedTy = + TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); + + if (FixedTy.isNull() && 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->getStorageClass() == VarDecl::Static) + Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) + << SizeRange; + else + Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) + << SizeRange; + return NewVD->setInvalidDecl(); + } + + if (FixedTy.isNull()) { + if (NewVD->isFileVarDecl()) + Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); + else + Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); + return NewVD->setInvalidDecl(); + } + + Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); + NewVD->setType(FixedTy); + } + + if (Previous.empty() && NewVD->isExternC()) { + // Since we did not find anything by this name and we're declaring + // an extern "C" variable, look for a non-visible extern "C" + // declaration with the same name. + llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos + = LocallyScopedExternalDecls.find(NewVD->getDeclName()); + if (Pos != LocallyScopedExternalDecls.end()) + Previous.addDecl(Pos->second); + } + + if (T->isVoidType() && !NewVD->hasExternalStorage()) { + Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) + << T; + return NewVD->setInvalidDecl(); + } + + if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { + Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); + return NewVD->setInvalidDecl(); + } + + if (isVM && NewVD->hasAttr<BlocksAttr>()) { + Diag(NewVD->getLocation(), diag::err_block_on_vm); + return NewVD->setInvalidDecl(); + } + + if (!Previous.empty()) { + Redeclaration = true; + MergeVarDecl(NewVD, Previous); + } +} + +/// \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 constructor 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.first != Path.Decls.second; + ++Path.Decls.first) { + if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { + if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) + return true; + } + } + + return false; +} + +/// AddOverriddenMethods - See if a method overrides any in the base classes, +/// and if so, check that it's a valid override and remember it. +void 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; + 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)) { + if (!CheckOverridingFunctionReturnType(MD, OldMD) && + !CheckOverridingFunctionExceptionSpec(MD, OldMD) && + !CheckOverridingFunctionAttributes(MD, OldMD)) + MD->addOverriddenMethod(OldMD->getCanonicalDecl()); + } + } + } +} + +NamedDecl* +Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, + QualType R, TypeSourceInfo *TInfo, + LookupResult &Previous, + MultiTemplateParamsArg TemplateParamLists, + bool IsFunctionDefinition, bool &Redeclaration) { + assert(R.getTypePtr()->isFunctionType()); + + DeclarationName Name = GetNameForDeclarator(D); + FunctionDecl::StorageClass SC = FunctionDecl::None; + switch (D.getDeclSpec().getStorageClassSpec()) { + default: assert(0 && "Unknown storage class!"); + case DeclSpec::SCS_auto: + case DeclSpec::SCS_register: + case DeclSpec::SCS_mutable: + Diag(D.getDeclSpec().getStorageClassSpecLoc(), + diag::err_typecheck_sclass_func); + D.setInvalidType(); + break; + case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; + case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; + case DeclSpec::SCS_static: { + if (CurContext->getLookupContext()->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). + Diag(D.getDeclSpec().getStorageClassSpecLoc(), + diag::err_static_block_func); + SC = FunctionDecl::None; + } else + SC = FunctionDecl::Static; + break; + } + case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; + } + + if (D.getDeclSpec().isThreadSpecified()) + Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); + + bool isFriend = D.getDeclSpec().isFriendSpecified(); + bool isInline = D.getDeclSpec().isInlineSpecified(); + bool isVirtual = D.getDeclSpec().isVirtualSpecified(); + bool isExplicit = D.getDeclSpec().isExplicitSpecified(); + + DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); + FunctionDecl::StorageClass SCAsWritten + = StorageClassSpecToFunctionDeclStorageClass(SCSpec, DC); + + // 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() && + RequireNonAbstractType(D.getIdentifierLoc(), + R->getAs<FunctionType>()->getResultType(), + diag::err_abstract_type_in_decl, + AbstractReturnType)) + D.setInvalidType(); + + // Do not allow returning a objc interface by-value. + if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { + Diag(D.getIdentifierLoc(), + diag::err_object_cannot_be_passed_returned_by_value) << 0 + << R->getAs<FunctionType>()->getResultType(); + D.setInvalidType(); + } + + bool isVirtualOkay = false; + FunctionDecl *NewFD; + + if (isFriend) { + // C++ [class.friend]p5 + // A function can be defined in a friend declaration of a + // class . . . . Such a function is implicitly inline. + isInline |= IsFunctionDefinition; + } + + if (Name.getNameKind() == DeclarationName::CXXConstructorName) { + // This is a C++ constructor declaration. + assert(DC->isRecord() && + "Constructors can only be declared in a member context"); + + R = CheckConstructorDeclarator(D, R, SC); + + // Create the new declaration + NewFD = CXXConstructorDecl::Create(Context, + cast<CXXRecordDecl>(DC), + D.getIdentifierLoc(), Name, R, TInfo, + isExplicit, isInline, + /*isImplicitlyDeclared=*/false); + } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { + // This is a C++ destructor declaration. + if (DC->isRecord()) { + R = CheckDestructorDeclarator(D, SC); + + NewFD = CXXDestructorDecl::Create(Context, + cast<CXXRecordDecl>(DC), + D.getIdentifierLoc(), Name, R, + isInline, + /*isImplicitlyDeclared=*/false); + NewFD->setTypeSourceInfo(TInfo); + + isVirtualOkay = true; + } else { + Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); + + // Create a FunctionDecl to satisfy the function definition parsing + // code path. + NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), + Name, R, TInfo, SC, SCAsWritten, isInline, + /*hasPrototype=*/true); + D.setInvalidType(); + } + } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { + if (!DC->isRecord()) { + Diag(D.getIdentifierLoc(), + diag::err_conv_function_not_member); + return 0; + } + + CheckConversionDeclarator(D, R, SC); + NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), + D.getIdentifierLoc(), Name, R, TInfo, + isInline, isExplicit); + + isVirtualOkay = true; + } else if (DC->isRecord()) { + // If the 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). + // must have an invalid constructor that has a return type + if (Name.getAsIdentifierInfo() && + Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ + Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) + << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) + << SourceRange(D.getIdentifierLoc()); + return 0; + } + + bool isStatic = SC == FunctionDecl::Static; + + // [class.free]p1: + // Any allocation function for a class T is a static member + // (even if not explicitly declared static). + if (Name.getCXXOverloadedOperator() == OO_New || + Name.getCXXOverloadedOperator() == OO_Array_New) + isStatic = true; + + // [class.free]p6 Any deallocation function for a class X is a static member + // (even if not explicitly declared static). + if (Name.getCXXOverloadedOperator() == OO_Delete || + Name.getCXXOverloadedOperator() == OO_Array_Delete) + isStatic = true; + + // This is a C++ method declaration. + NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), + D.getIdentifierLoc(), Name, R, TInfo, + isStatic, SCAsWritten, isInline); + + isVirtualOkay = !isStatic; + } else { + // Determine whether the function was written with a + // prototype. This true when: + // - we're in C++ (where every function has a prototype), + // - 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 = + getLangOptions().CPlusPlus || + (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || + (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); + + NewFD = FunctionDecl::Create(Context, DC, + D.getIdentifierLoc(), + Name, R, TInfo, SC, SCAsWritten, isInline, + HasPrototype); + } + + if (D.isInvalidType()) + NewFD->setInvalidDecl(); + + SetNestedNameSpecifier(NewFD, D); + + // Set the lexical context. If the declarator has a C++ + // scope specifier, or is the object of a friend declaration, the + // lexical context will be different from the semantic context. + NewFD->setLexicalDeclContext(CurContext); + + // Match up the template parameter lists with the scope specifier, then + // determine whether we have a template or a template specialization. + FunctionTemplateDecl *FunctionTemplate = 0; + bool isExplicitSpecialization = false; + bool isFunctionTemplateSpecialization = false; + if (TemplateParameterList *TemplateParams + = MatchTemplateParametersToScopeSpecifier( + D.getDeclSpec().getSourceRange().getBegin(), + D.getCXXScopeSpec(), + (TemplateParameterList**)TemplateParamLists.get(), + TemplateParamLists.size(), + isFriend, + isExplicitSpecialization)) { + if (TemplateParams->size() > 0) { + // This is a function template + + // Check that we can declare a template here. + if (CheckTemplateDeclScope(S, TemplateParams)) + return 0; + + FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, + NewFD->getLocation(), + Name, TemplateParams, + NewFD); + FunctionTemplate->setLexicalDeclContext(CurContext); + NewFD->setDescribedFunctionTemplate(FunctionTemplate); + } else { + // This is a function template specialization. + isFunctionTemplateSpecialization = true; + + // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". + if (isFriend && isFunctionTemplateSpecialization) { + // 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, "<>"); + } + } + + // FIXME: Free this memory properly. + TemplateParamLists.release(); + } + + // 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 { + // Okay: Add virtual to the method. + CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); + CurClass->setMethodAsVirtual(NewFD); + } + } + + // 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()); + } + } + + // Filter out previous declarations that don't match the scope. + FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); + + if (isFriend) { + // DC is the namespace in which the function is being declared. + assert((DC->isFileContext() || !Previous.empty()) && + "previously-undeclared friend function being created " + "in a non-namespace context"); + + // For now, claim that the objects have no previous declaration. + if (FunctionTemplate) { + FunctionTemplate->setObjectOfFriendDecl(false); + FunctionTemplate->setAccess(AS_public); + } + NewFD->setObjectOfFriendDecl(false); + NewFD->setAccess(AS_public); + } + + if (SC == FunctionDecl::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()); + } + + // 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(Context, SE->getString())); + } + + // Copy the parameter declarations from the declarator D to the function + // declaration NewFD, if they are available. First scavenge them into Params. + llvm::SmallVector<ParmVarDecl*, 16> Params; + if (D.getNumTypeObjects() > 0) { + DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; + + // 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 && + FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { + // Empty arg list, don't push any params. + ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); + + // In C++, the empty parameter-type-list must be spelled "void"; a + // typedef of void is not permitted. + if (getLangOptions().CPlusPlus && + Param->getType().getUnqualifiedType() != Context.VoidTy) + Diag(Param->getLocation(), diag::err_param_typedef_of_void); + // FIXME: Leaks decl? + } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { + for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { + ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); + 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 = ParmVarDecl::Create(Context, NewFD, + D.getIdentifierLoc(), 0, + *AI, + Context.getTrivialTypeSourceInfo(*AI, + D.getIdentifierLoc()), + VarDecl::None, + VarDecl::None, 0); + Param->setImplicit(); + 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.data(), Params.size()); + + // If the declarator is a template-id, translate the parser's template + // argument list into our AST format. + bool HasExplicitTemplateArgs = false; + TemplateArgumentListInfo TemplateArgs; + if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { + TemplateIdAnnotation *TemplateId = D.getName().TemplateId; + TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); + TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); + ASTTemplateArgsPtr TemplateArgsPtr(*this, + TemplateId->getTemplateArgs(), + TemplateId->NumArgs); + translateTemplateArguments(TemplateArgsPtr, + TemplateArgs); + TemplateArgsPtr.release(); + + HasExplicitTemplateArgs = true; + + if (FunctionTemplate) { + // FIXME: Diagnose function template with explicit template + // arguments. + 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). + Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) + << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) + << FixItHint::CreateInsertion( + D.getDeclSpec().getSourceRange().getBegin(), + "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. + if (isFunctionTemplateSpecialization && isFriend && + (NewFD->getType()->isDependentType() || DC->isDependentContext())) { + assert(HasExplicitTemplateArgs && + "friend function specialization without template args"); + if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, + Previous)) + NewFD->setInvalidDecl(); + } else if (isFunctionTemplateSpecialization) { + if (CheckFunctionTemplateSpecialization(NewFD, + (HasExplicitTemplateArgs ? &TemplateArgs : 0), + Previous)) + NewFD->setInvalidDecl(); + } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { + if (CheckMemberSpecialization(NewFD, Previous)) + NewFD->setInvalidDecl(); + } + + // Perform semantic checking on the function declaration. + bool OverloadableAttrRequired = false; // FIXME: HACK! + CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, + Redeclaration, /*FIXME:*/OverloadableAttrRequired); + + assert((NewFD->isInvalidDecl() || !Redeclaration || + Previous.getResultKind() != LookupResult::FoundOverloaded) && + "previous declaration set still overloaded"); + + NamedDecl *PrincipalDecl = (FunctionTemplate + ? cast<NamedDecl>(FunctionTemplate) + : NewFD); + + if (isFriend && Redeclaration) { + AccessSpecifier Access = AS_public; + if (!NewFD->isInvalidDecl()) + Access = NewFD->getPreviousDeclaration()->getAccess(); + + NewFD->setAccess(Access); + if (FunctionTemplate) FunctionTemplate->setAccess(Access); + + PrincipalDecl->setObjectOfFriendDecl(true); + } + + 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->getPreviousDeclaration(); + CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), + PrevTemplate? PrevTemplate->getTemplateParameters() : 0, + D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate + : TPC_FunctionTemplate); + } + + if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { + // Fake up an access specifier if it's supposed to be a class member. + if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) + NewFD->setAccess(AS_public); + + // 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. + if (!IsFunctionDefinition && !isFriend && + !isFunctionTemplateSpecialization && !isExplicitSpecialization) { + Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) + << D.getCXXScopeSpec().getRange(); + NewFD->setInvalidDecl(); + } else if (!Redeclaration && + !(isFriend && CurContext->isDependentContext())) { + // 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). + Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) + << Name << DC << D.getCXXScopeSpec().getRange(); + NewFD->setInvalidDecl(); + + LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, + ForRedeclaration); + LookupQualifiedName(Prev, DC); + assert(!Prev.isAmbiguous() && + "Cannot have an ambiguity in previous-declaration lookup"); + for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); + Func != FuncEnd; ++Func) { + if (isa<FunctionDecl>(*Func) && + isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) + Diag((*Func)->getLocation(), diag::note_member_def_close_match); + } + } + } + + // Handle attributes. We need to have merged decls when handling attributes + // (for example to check for conflicts, etc). + // FIXME: This needs to happen before we merge declarations. Then, + // let attribute merging cope with attribute conflicts. + ProcessDeclAttributes(S, NewFD, D); + + // attributes declared post-definition are currently ignored + if (Redeclaration && Previous.isSingleResult()) { + const FunctionDecl *Def; + FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); + if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { + Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); + Diag(Def->getLocation(), diag::note_previous_definition); + } + } + + AddKnownFunctionAttributes(NewFD); + + if (OverloadableAttrRequired && !NewFD->getAttr<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; + if (!Previous.empty()) + Diag(Previous.getRepresentativeDecl()->getLocation(), + diag::note_attribute_overloadable_prev_overload); + NewFD->addAttr(::new (Context) OverloadableAttr()); + } + + // If this is a locally-scoped extern C function, update the + // map of such names. + if (CurContext->isFunctionOrMethod() && NewFD->isExternC() + && !NewFD->isInvalidDecl()) + RegisterLocallyScopedExternCDecl(NewFD, Previous, S); + + // Set this FunctionDecl's range up to the right paren. + NewFD->setLocEnd(D.getSourceRange().getEnd()); + + if (FunctionTemplate && NewFD->isInvalidDecl()) + FunctionTemplate->setInvalidDecl(); + + if (FunctionTemplate) + return FunctionTemplate; + + + // Keep track of static, non-inlined function definitions that + // have not been used. We will warn later. + // FIXME: Also include static functions declared but not defined. + if (!NewFD->isInvalidDecl() && IsFunctionDefinition + && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage + && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() + && !NewFD->hasAttr<ConstructorAttr>() + && !NewFD->hasAttr<DestructorAttr>()) + UnusedStaticFuncs.push_back(NewFD); + + 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 IsExplicitSpecialiation whether this new function declaration is +/// an explicit specialization of the previous declaration. +/// +/// This sets NewFD->isInvalidDecl() to true if there was an error. +void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, + LookupResult &Previous, + bool IsExplicitSpecialization, + bool &Redeclaration, + bool &OverloadableAttrRequired) { + // If NewFD is already known erroneous, don't do any of this checking. + if (NewFD->isInvalidDecl()) + return; + + if (NewFD->getResultType()->isVariablyModifiedType()) { + // Functions returning a variably modified type violate C99 6.7.5.2p2 + // because all functions have linkage. + Diag(NewFD->getLocation(), diag::err_vm_func_decl); + return NewFD->setInvalidDecl(); + } + + if (NewFD->isMain()) + CheckMain(NewFD); + + // Check for a previous declaration of this name. + if (Previous.empty() && NewFD->isExternC()) { + // Since we did not find anything by this name and we're declaring + // an extern "C" function, look for a non-visible extern "C" + // declaration with the same name. + llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos + = LocallyScopedExternalDecls.find(NewFD->getDeclName()); + if (Pos != LocallyScopedExternalDecls.end()) + Previous.addDecl(Pos->second); + } + + // 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. + + NamedDecl *OldDecl = 0; + if (!AllowOverloadingOfFunction(Previous, Context)) { + Redeclaration = true; + OldDecl = Previous.getFoundDecl(); + } else { + if (!getLangOptions().CPlusPlus) { + OverloadableAttrRequired = true; + + // Functions marked "overloadable" must have a prototype (that + // we can't get through declaration merging). + if (!NewFD->getType()->getAs<FunctionProtoType>()) { + Diag(NewFD->getLocation(), + diag::err_attribute_overloadable_no_prototype) + << NewFD; + Redeclaration = true; + + // Turn this into a variadic function with no parameters. + QualType R = Context.getFunctionType( + NewFD->getType()->getAs<FunctionType>()->getResultType(), + 0, 0, true, 0, false, false, 0, 0, + FunctionType::ExtInfo()); + NewFD->setType(R); + return NewFD->setInvalidDecl(); + } + } + + switch (CheckOverload(NewFD, Previous, OldDecl)) { + case Ovl_Match: + Redeclaration = true; + if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { + HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); + Redeclaration = false; + } + break; + + case Ovl_NonFunction: + Redeclaration = true; + break; + + case Ovl_Overload: + Redeclaration = false; + break; + } + } + + if (Redeclaration) { + // NewFD and OldDecl represent declarations that need to be + // merged. + if (MergeFunctionDecl(NewFD, OldDecl)) + return NewFD->setInvalidDecl(); + + 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 { + if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions + NewFD->setAccess(OldDecl->getAccess()); + NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); + } + } + } + + // Semantic checking for this function declaration (in isolation). + if (getLangOptions().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 thisc heck 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); + return NewFD->setInvalidDecl(); + } + } + + Record->setUserDeclaredDestructor(true); + // C++ [class]p4: A POD-struct is an aggregate class that has [...] no + // user-defined destructor. + Record->setPOD(false); + + // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- + // declared destructor. + // FIXME: C++0x: don't do this for "= default" destructors + Record->setHasTrivialDestructor(false); + } 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()) + AddOverriddenMethods(Method->getParent(), Method); + } + + // Additional checks for the destructor; make sure we do this after we + // figure out whether the destructor is virtual. + if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) + if (!Destructor->getParent()->isDependentType()) + CheckDestructor(Destructor); + + // Extra checking for C++ overloaded operators (C++ [over.oper]). + if (NewFD->isOverloadedOperator() && + CheckOverloadedOperatorDeclaration(NewFD)) + return NewFD->setInvalidDecl(); + + // Extra checking for C++0x literal operators (C++0x [over.literal]). + if (NewFD->getLiteralIdentifier() && + CheckLiteralOperatorDeclaration(NewFD)) + return NewFD->setInvalidDecl(); + + // 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); + } +} + +void Sema::CheckMain(FunctionDecl* FD) { + // C++ [basic.start.main]p3: A program that declares main to be inline + // or static is ill-formed. + // C99 6.7.4p4: In a hosted environment, the inline function specifier + // shall not appear in a declaration of main. + // static main is not an error under C99, but we should warn about it. + bool isInline = FD->isInlineSpecified(); + bool isStatic = FD->getStorageClass() == FunctionDecl::Static; + if (isInline || isStatic) { + unsigned diagID = diag::warn_unusual_main_decl; + if (isInline || getLangOptions().CPlusPlus) + diagID = diag::err_unusual_main_decl; + + int which = isStatic + (isInline << 1) - 1; + Diag(FD->getLocation(), diagID) << which; + } + + QualType T = FD->getType(); + assert(T->isFunctionType() && "function decl is not of function type"); + const FunctionType* FT = T->getAs<FunctionType>(); + + if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { + // TODO: add a replacement fixit to turn the return type into 'int'. + 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.Target.getTriple().getOS() == llvm::Triple::Darwin) + 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>()) && + (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); + } +} + +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)) + return false; + Diag(Init->getExprLoc(), diag::err_init_element_not_constant) + << Init->getSourceRange(); + return true; +} + +void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { + AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); +} + +/// 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(DeclPtrTy dcl, ExprArg init, bool DirectInit) { + Decl *RealDecl = dcl.getAs<Decl>(); + // If there is no declaration, there was an error parsing it. Just ignore + // the initializer. + if (RealDecl == 0) + 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; + Expr *Init = static_cast<Expr *>(init.get()); + 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) { + if (getLangOptions().CPlusPlus && + RealDecl->getLexicalDeclContext()->isRecord() && + isa<NamedDecl>(RealDecl)) + Diag(RealDecl->getLocation(), diag::err_member_initialization) + << cast<NamedDecl>(RealDecl)->getDeclName(); + else + Diag(RealDecl->getLocation(), diag::err_illegal_initializer); + RealDecl->setInvalidDecl(); + return; + } + + // 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; + } + + // Take ownership of the expression, now that we're sure we have somewhere + // to put it. + Expr *Init = init.takeAs<Expr>(); + assert(Init && "missing initializer"); + + // Capture the variable that is being initialized and the style of + // initialization. + InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); + + // FIXME: Poor source location information. + InitializationKind Kind + = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), + Init->getLocStart(), + Init->getLocEnd()) + : InitializationKind::CreateCopy(VDecl->getLocation(), + Init->getLocStart()); + + // Get the decls type and save a reference for later, since + // CheckInitializerTypes may change it. + QualType DclT = VDecl->getType(), SavT = DclT; + if (VDecl->isBlockVarDecl()) { + if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 + Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); + VDecl->setInvalidDecl(); + } else if (!VDecl->isInvalidDecl()) { + InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); + OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, + MultiExprArg(*this, (void**)&Init, 1), + &DclT); + if (Result.isInvalid()) { + VDecl->setInvalidDecl(); + return; + } + + Init = Result.takeAs<Expr>(); + + // C++ 3.6.2p2, allow dynamic initialization of static initializers. + // Don't check invalid declarations to avoid emitting useless diagnostics. + if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { + if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. + CheckForConstantInitializer(Init, DclT); + } + } + } 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; + // }; + + // Attach the initializer + VDecl->setInit(Init); + + // 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. + QualType T = VDecl->getType(); + if (!T->isDependentType() && + (!Context.getCanonicalType(T).isConstQualified() || + !T->isIntegralType())) { + Diag(VDecl->getLocation(), diag::err_member_initialization) + << VDecl->getDeclName() << Init->getSourceRange(); + VDecl->setInvalidDecl(); + } else { + // 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). + if (!Init->isTypeDependent() && + !Init->getType()->isIntegralType()) { + // We have a non-dependent, non-integral or enumeration type. + Diag(Init->getSourceRange().getBegin(), + diag::err_in_class_initializer_non_integral_type) + << Init->getType() << Init->getSourceRange(); + VDecl->setInvalidDecl(); + } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { + // Check whether the expression is a constant expression. + llvm::APSInt Value; + SourceLocation Loc; + if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { + Diag(Loc, diag::err_in_class_initializer_non_constant) + << Init->getSourceRange(); + VDecl->setInvalidDecl(); + } else if (!VDecl->getType()->isDependentType()) + ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); + } + } + } else if (VDecl->isFileVarDecl()) { + if (VDecl->getStorageClass() == VarDecl::Extern && + (!getLangOptions().CPlusPlus || + !Context.getBaseElementType(VDecl->getType()).isConstQualified())) + Diag(VDecl->getLocation(), diag::warn_extern_init); + if (!VDecl->isInvalidDecl()) { + InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); + OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, + MultiExprArg(*this, (void**)&Init, 1), + &DclT); + if (Result.isInvalid()) { + VDecl->setInvalidDecl(); + return; + } + + Init = Result.takeAs<Expr>(); + } + + // C++ 3.6.2p2, allow dynamic initialization of static initializers. + // Don't check invalid declarations to avoid emitting useless diagnostics. + if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { + // C99 6.7.8p4. All file scoped initializers need to be constant. + CheckForConstantInitializer(Init, DclT); + } + } + // 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 a VariableArrayType to a ConstantArrayType. + if (!VDecl->isInvalidDecl() && (DclT != SavT)) { + VDecl->setType(DclT); + Init->setType(DclT); + } + + Init = MaybeCreateCXXExprWithTemporaries(Init); + // Attach the initializer to the decl. + VDecl->setInit(Init); + + if (getLangOptions().CPlusPlus) { + // Make sure we mark the destructor as used if necessary. + QualType InitType = VDecl->getType(); + while (const ArrayType *Array = Context.getAsArrayType(InitType)) + InitType = Context.getBaseElementType(Array); + if (const RecordType *Record = InitType->getAs<RecordType>()) + FinalizeVarWithDestructor(VDecl, Record); + } + + return; +} + +/// 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(DeclPtrTy dcl) { + // Our main concern here is re-establishing invariants like "a + // variable's type is either dependent or complete". + Decl *D = dcl.getAs<Decl>(); + if (!D || D->isInvalidDecl()) return; + + VarDecl *VD = dyn_cast<VarDecl>(D); + if (!VD) 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(DeclPtrTy dcl, + bool TypeContainsUndeducedAuto) { + Decl *RealDecl = dcl.getAs<Decl>(); + + // 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++0x [dcl.spec.auto]p3 + if (TypeContainsUndeducedAuto) { + Diag(Var->getLocation(), diag::err_auto_var_requires_init) + << Var->getDeclName() << Type; + 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->isBlockVarDecl() && + !Var->getLinkage() && !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(); + 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() == VarDecl::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->getPreviousDeclaration() == 0) + RequireCompleteType(Var->getLocation(), Type, + diag::ext_typecheck_decl_incomplete_type); + } + } + + // Record the tentative definition; we're done. + if (!Var->isInvalidDecl()) + TentativeDefinitions.push_back(Var); + return; + } + + // Provide a specific diagnostic for uninitialized variable + // definitions with incomplete array type. + if (Type->isIncompleteArrayType()) { + Diag(Var->getLocation(), + diag::err_typecheck_incomplete_array_needs_initializer); + Var->setInvalidDecl(); + return; + } + + // Provide a specific diagnostic for uninitialized variable + // definitions with reference type. + if (Type->isReferenceType()) { + Diag(Var->getLocation(), diag::err_reference_var_requires_init) + << Var->getDeclName() + << SourceRange(Var->getLocation(), Var->getLocation()); + Var->setInvalidDecl(); + return; + } + + // Do not attempt to type-check the default initializer for a + // variable with dependent type. + if (Type->isDependentType()) + return; + + if (Var->isInvalidDecl()) + return; + + if (RequireCompleteType(Var->getLocation(), + Context.getBaseElementType(Type), + diag::err_typecheck_decl_incomplete_type)) { + Var->setInvalidDecl(); + return; + } + + // The variable can not have an abstract class type. + if (RequireNonAbstractType(Var->getLocation(), Type, + diag::err_abstract_type_in_decl, + AbstractVariableType)) { + Var->setInvalidDecl(); + return; + } + + const RecordType *Record + = Context.getBaseElementType(Type)->getAs<RecordType>(); + if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && + cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { + // 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. + // FIXME: DPG thinks it is very fishy that C++0x disables this. + } else { + InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); + InitializationKind Kind + = InitializationKind::CreateDefault(Var->getLocation()); + + InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); + OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, + MultiExprArg(*this, 0, 0)); + if (Init.isInvalid()) + Var->setInvalidDecl(); + else if (Init.get()) + Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); + } + + if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) + FinalizeVarWithDestructor(Var, Record); + } +} + +Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, + DeclPtrTy *Group, + unsigned NumDecls) { + llvm::SmallVector<Decl*, 8> Decls; + + if (DS.isTypeSpecOwned()) + Decls.push_back((Decl*)DS.getTypeRep()); + + for (unsigned i = 0; i != NumDecls; ++i) + if (Decl *D = Group[i].getAs<Decl>()) + Decls.push_back(D); + + return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, + Decls.data(), Decls.size())); +} + + +/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() +/// to introduce parameters into function prototype scope. +Sema::DeclPtrTy +Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { + const DeclSpec &DS = D.getDeclSpec(); + + // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. + VarDecl::StorageClass StorageClass = VarDecl::None; + VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; + if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { + StorageClass = VarDecl::Register; + StorageClassAsWritten = VarDecl::Register; + } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { + Diag(DS.getStorageClassSpecLoc(), + diag::err_invalid_storage_class_in_func_decl); + D.getMutableDeclSpec().ClearStorageClassSpecs(); + } + + if (D.getDeclSpec().isThreadSpecified()) + Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); + + DiagnoseFunctionSpecifiers(D); + + // Check that there are no default arguments inside the type of this + // parameter (C++ only). + if (getLangOptions().CPlusPlus) + CheckExtraCXXDefaultArguments(D); + + TypeSourceInfo *TInfo = 0; + TagDecl *OwnedDecl = 0; + QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); + + if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { + // C++ [dcl.fct]p6: + // Types shall not be defined in return or parameter types. + Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) + << Context.getTypeDeclType(OwnedDecl); + } + + // Check for redeclaration of parameters, e.g. int foo(int x, int x); + IdentifierInfo *II = D.getIdentifier(); + 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(DeclPtrTy::make(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(), + TInfo, parmDeclType, II, + D.getIdentifierLoc(), + StorageClass, StorageClassAsWritten); + + if (D.isInvalidType()) + New->setInvalidDecl(); + + // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). + if (D.getCXXScopeSpec().isSet()) { + Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) + << D.getCXXScopeSpec().getRange(); + New->setInvalidDecl(); + } + + // Add the parameter declaration into this scope. + S->AddDecl(DeclPtrTy::make(New)); + if (II) + IdResolver.AddDecl(New); + + ProcessDeclAttributes(S, New, D); + + if (New->hasAttr<BlocksAttr>()) { + Diag(New->getLocation(), diag::err_block_on_nonlocal); + } + return DeclPtrTy::make(New); +} + +ParmVarDecl *Sema::CheckParameter(DeclContext *DC, + TypeSourceInfo *TSInfo, QualType T, + IdentifierInfo *Name, + SourceLocation NameLoc, + VarDecl::StorageClass StorageClass, + VarDecl::StorageClass StorageClassAsWritten) { + ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, + adjustParameterType(T), TSInfo, + StorageClass, StorageClassAsWritten, + 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()) { + Diag(NameLoc, + diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; + New->setInvalidDecl(); + } + + // 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) { + assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && + "Not a function declarator!"); + DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; + + // 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) { + llvm::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. + DeclSpec DS; + const char* PrevSpec; // unused + unsigned DiagID; // unused + DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, + PrevSpec, DiagID); + Declarator ParamD(DS, Declarator::KNRTypeListContext); + ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); + FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); + } + } + } +} + +Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, + Declarator &D) { + assert(getCurFunctionDecl() == 0 && "Function parsing confused"); + assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && + "Not a function declarator!"); + DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; + + if (FTI.hasPrototype) { + // FIXME: Diagnose arguments without names in C. + } + + Scope *ParentScope = FnBodyScope->getParent(); + + DeclPtrTy DP = HandleDeclarator(ParentScope, D, + MultiTemplateParamsArg(*this), + /*IsFunctionDefinition=*/true); + return ActOnStartOfFunctionDef(FnBodyScope, DP); +} + +static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { + // 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->isInlineSpecified()) + 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; + + bool MissingPrototype = true; + for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); + Prev; Prev = Prev->getPreviousDeclaration()) { + // Ignore any declarations that occur in function or method + // scope, because they aren't visible from the header. + if (Prev->getDeclContext()->isFunctionOrMethod()) + continue; + + MissingPrototype = !Prev->getType()->isFunctionProtoType(); + break; + } + + return MissingPrototype; +} + +Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { + // Clear the last template instantiation error context. + LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); + + if (!D) + return D; + FunctionDecl *FD = 0; + + if (FunctionTemplateDecl *FunTmpl + = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) + FD = FunTmpl->getTemplatedDecl(); + else + FD = cast<FunctionDecl>(D.getAs<Decl>()); + + // Enter a new function scope + PushFunctionScope(); + + // See if this is a redefinition. + // But don't complain if we're in GNU89 mode and the previous definition + // was an extern inline function. + const FunctionDecl *Definition; + if (FD->getBody(Definition) && + !canRedefineFunction(Definition, getLangOptions())) { + Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); + Diag(Definition->getLocation(), diag::note_previous_definition); + } + + // Builtin functions cannot be defined. + if (unsigned BuiltinID = FD->getBuiltinID()) { + if (!Context.BuiltinInfo.isPredefinedLibFunction(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. + if (ShouldWarnAboutMissingPrototype(FD)) + Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; + + if (FnBodyScope) + PushDeclContext(FnBodyScope, FD); + + // Check the validity of our function parameters + CheckParmsForFunctionDef(FD); + + bool ShouldCheckShadow = + Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; + + // 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) { + if (ShouldCheckShadow) + CheckShadow(FnBodyScope, Param); + + PushOnScopeChains(Param, FnBodyScope); + } + } + + // Checking attributes of current function definition + // dllimport attribute. + if (FD->getAttr<DLLImportAttr>() && + (!FD->getAttr<DLLExportAttr>())) { + // dllimport attribute cannot be applied to definition. + if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { + Diag(FD->getLocation(), + diag::err_attribute_can_be_applied_only_to_symbol_declaration) + << "dllimport"; + FD->setInvalidDecl(); + return DeclPtrTy::make(FD); + } + + // Visual C++ appears to not think this is an issue, so only issue + // a warning when Microsoft extensions are disabled. + if (!LangOpts.Microsoft) { + // 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->getNameAsCString() << "dllimport"; + } + } + return DeclPtrTy::make(FD); +} + +/// \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. +static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { + const VarDecl *NRVOCandidate = 0; + for (unsigned I = 0; I != NumReturns; ++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); +} + +Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { + return ActOnFinishFunctionBody(D, move(BodyArg), false); +} + +Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, + bool IsInstantiation) { + Decl *dcl = D.getAs<Decl>(); + Stmt *Body = BodyArg.takeAs<Stmt>(); + + 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(); + + if (FD) { + FD->setBody(Body); + if (FD->isMain()) { + // C and C++ allow for main to automagically return 0. + // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. + FD->setHasImplicitReturnZero(true); + WP.disableCheckFallThrough(); + } + + if (!FD->isInvalidDecl()) { + DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); + + // If this is a constructor, we need a vtable. + if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) + MarkVTableUsed(FD->getLocation(), Constructor->getParent()); + + ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), + FunctionScopes.back()->Returns.size()); + } + + assert(FD == getCurFunctionDecl() && "Function parsing confused"); + } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { + assert(MD == getCurMethodDecl() && "Method parsing confused"); + MD->setBody(Body); + MD->setEndLoc(Body->getLocEnd()); + if (!MD->isInvalidDecl()) + DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); + } else { + Body->Destroy(Context); + return DeclPtrTy(); + } + + // Verify and clean out per-function state. + + // Check goto/label use. + for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator + I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { + LabelStmt *L = I->second; + + // 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->getSubStmt() != 0) + continue; + + // Emit error. + Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); + + // At this point, we have gotos that use the bogus label. Stitch it into + // the function body so that they aren't leaked and that the AST is well + // formed. + if (Body == 0) { + // The whole function wasn't parsed correctly, just delete this. + L->Destroy(Context); + continue; + } + + // Otherwise, the body is valid: we want to stitch the label decl into the + // function somewhere so that it is properly owned and so that the goto + // has a valid target. Do this by creating a new compound stmt with the + // label in it. + + // Give the label a sub-statement. + L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); + + CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? + cast<CXXTryStmt>(Body)->getTryBlock() : + cast<CompoundStmt>(Body); + llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), + Compound->body_end()); + Elements.push_back(L); + Compound->setStmts(Context, Elements.data(), Elements.size()); + } + + 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 that gotos and switch cases don't jump into scopes illegally. + // Verify that that gotos and switch cases don't jump into scopes illegally. + if (FunctionNeedsScopeChecking() && + !dcl->isInvalidDecl() && + !hasAnyErrorsInThisFunction()) + DiagnoseInvalidJumps(Body); + + if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) + 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()) + ExprTemporaries.clear(); + else if (!isa<FunctionTemplateDecl>(dcl)) { + // Since the body is valid, issue any analysis-based warnings that are + // enabled. + QualType ResultType; + if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { + ResultType = FD->getResultType(); + } + else { + ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); + ResultType = MD->getResultType(); + } + AnalysisWarnings.IssueWarnings(WP, dcl); + } + + assert(ExprTemporaries.empty() && "Leftover temporaries in function"); + } + + if (!IsInstantiation) + PopDeclContext(); + + PopFunctionOrBlockScope(); + + // 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()) + ExprTemporaries.clear(); + + return D; +} + +/// 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. + llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos + = LocallyScopedExternalDecls.find(&II); + if (Pos != LocallyScopedExternalDecls.end()) { + Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; + Diag(Pos->second->getLocation(), diag::note_previous_declaration); + return Pos->second; + } + + // Extension in C99. Legal in C90, but warn about it. + if (II.getName().startswith("__builtin_")) + Diag(Loc, diag::warn_builtin_unknown) << &II; + else if (getLangOptions().C99) + Diag(Loc, diag::ext_implicit_function_decl) << &II; + else + Diag(Loc, diag::warn_implicit_function_decl) << &II; + + // Set a Declarator for the implicit definition: int foo(); + const char *Dummy; + DeclSpec DS; + unsigned DiagID; + bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); + Error = Error; // Silence warning. + assert(!Error && "Error setting up implicit decl!"); + Declarator D(DS, Declarator::BlockContext); + D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, + 0, 0, false, SourceLocation(), + false, 0,0,0, Loc, Loc, D), + SourceLocation()); + D.SetIdentifier(&II, Loc); + + // Insert this function into translation-unit scope. + + DeclContext *PrevDC = CurContext; + CurContext = Context.getTranslationUnitDecl(); + + FunctionDecl *FD = + dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); + 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. +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>()) + FD->addAttr(::new (Context) FormatAttr(Context, "printf", 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 (!getLangOptions().MathErrno && + Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { + if (!FD->getAttr<ConstAttr>()) + FD->addAttr(::new (Context) ConstAttr()); + } + + if (Context.BuiltinInfo.isNoReturn(BuiltinID)) + FD->setType(Context.getNoReturnType(FD->getType())); + if (Context.BuiltinInfo.isNoThrow(BuiltinID)) + FD->addAttr(::new (Context) NoThrowAttr()); + if (Context.BuiltinInfo.isConst(BuiltinID)) + FD->addAttr(::new (Context) ConstAttr()); + } + + IdentifierInfo *Name = FD->getIdentifier(); + if (!Name) + return; + if ((!getLangOptions().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("NSLog") || Name->isStr("NSLogv")) { + // FIXME: NSLog and NSLogv should be target specific + if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { + // FIXME: We known better than our headers. + const_cast<FormatAttr *>(Format)->setType(Context, "printf"); + } else + FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, + Name->isStr("NSLogv") ? 0 : 2)); + } else 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(Context, "printf", 2, + Name->isStr("vasprintf") ? 0 : 3)); + } +} + +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.getIdentifierLoc(), + D.getIdentifier(), + TInfo); + + if (const TagType *TT = T->getAs<TagType>()) { + TagDecl *TD = TT->getDecl(); + + // If the TagDecl that the TypedefDecl points to is an anonymous decl + // keep track of the TypedefDecl. + if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) + TD->setTypedefForAnonDecl(NewTD); + } + + if (D.isInvalidType()) + NewTD->setInvalidDecl(); + return NewTD; +} + + +/// \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, + 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 (OldTag == NewTag) + return true; + + if ((OldTag == TTK_Struct || OldTag == TTK_Class) && + (NewTag == TTK_Struct || NewTag == TTK_Class)) { + // Warn about the struct/class tag mismatch. + bool isTemplate = false; + if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) + isTemplate = Record->getDescribedClassTemplate(); + + Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) + << (NewTag == TTK_Class) + << isTemplate << &Name + << FixItHint::CreateReplacement(SourceRange(NewTagLoc), + OldTag == TTK_Class? "class" : "struct"); + Diag(Previous->getLocation(), diag::note_previous_use); + 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. +Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, + SourceLocation KWLoc, CXXScopeSpec &SS, + IdentifierInfo *Name, SourceLocation NameLoc, + AttributeList *Attr, AccessSpecifier AS, + MultiTemplateParamsArg TemplateParameterLists, + bool &OwnedDecl, bool &IsDependent) { + // If this is not a definition, it must have a name. + assert((Name != 0 || TUK == TUK_Definition) && + "Nameless record must be a definition!"); + + OwnedDecl = false; + TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); + + // FIXME: Check explicit specializations more carefully. + bool isExplicitSpecialization = false; + if (TUK != TUK_Reference) { + if (TemplateParameterList *TemplateParams + = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, + (TemplateParameterList**)TemplateParameterLists.get(), + TemplateParameterLists.size(), + TUK == TUK_Friend, + isExplicitSpecialization)) { + if (TemplateParams->size() > 0) { + // This is a declaration or definition of a class template (which may + // be a member of another template). + OwnedDecl = false; + DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, + SS, Name, NameLoc, Attr, + TemplateParams, + AS); + TemplateParameterLists.release(); + return Result.get(); + } else { + // The "template<>" header is extraneous. + Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) + << TypeWithKeyword::getTagTypeKindName(Kind) << Name; + isExplicitSpecialization = true; + } + } + + TemplateParameterLists.release(); + } + + DeclContext *SearchDC = CurContext; + DeclContext *DC = CurContext; + bool isStdBadAlloc = false; + bool Invalid = false; + + RedeclarationKind Redecl = ForRedeclaration; + if (TUK == TUK_Friend || TUK == TUK_Reference) + Redecl = NotForRedeclaration; + + LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); + + 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 DeclPtrTy(); + } + } else { + DC = computeDeclContext(SS, true); + if (!DC) { + Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) + << SS.getRange(); + return DeclPtrTy(); + } + } + + if (RequireCompleteDeclContext(SS, DC)) + return DeclPtrTy::make((Decl *)0); + + SearchDC = DC; + // Look-up name inside 'foo::'. + LookupQualifiedName(Previous, DC); + + if (Previous.isAmbiguous()) + return DeclPtrTy(); + + 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. + if (Previous.wasNotFoundInCurrentInstantiation()) { + IsDependent = true; + return DeclPtrTy(); + } + + // 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); + + // Note: there used to be some attempt at recovery here. + if (Previous.isAmbiguous()) + return DeclPtrTy(); + + if (!getLangOptions().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(); + } + } + + 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 (getLangOptions().CPlusPlus && Name && DC && StdNamespace && + DC->Equals(StdNamespace) && 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(StdBadAlloc); + } + } + + // 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->isRecord()) + SearchDC = SearchDC->getParent(); + + // Find the scope where we'll be declaring the tag. + while (S->isClassScope() || + (getLangOptions().CPlusPlus && + S->isFunctionPrototypeScope()) || + ((S->getFlags() & Scope::DeclScope) == 0) || + (S->getEntity() && + ((DeclContext *)S->getEntity())->isTransparentContext())) + S = S->getParent(); + } else { + assert(TUK == TUK_Friend); + // C++ [namespace.memdef]p3: + // If a friend declaration in a non-local class first declares a + // class or function, the friend class or function is a member of + // the innermost enclosing namespace. + SearchDC = SearchDC->getEnclosingNamespaceContext(); + } + + // In C++, we need to do a redeclaration lookup to properly + // diagnose some problems. + if (getLangOptions().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 (getLangOptions().CPlusPlus) { + if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { + if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { + TagDecl *Tag = TT->getDecl(); + if (Tag->getDeclName() == Name && + Tag->getDeclContext()->getLookupContext() + ->Equals(TD->getDeclContext()->getLookupContext())) { + PrevDecl = Tag; + Previous.clear(); + Previous.addDecl(Tag); + } + } + } + } + + 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)) { + // Make sure that this wasn't declared as an enum and now used as a + // struct or something similar. + if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, 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 (!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 || TUK == TUK_Friend) + return DeclPtrTy::make(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. + if (!isExplicitSpecialization || + !isa<CXXRecordDecl>(Def) || + cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() + == TSK_ExplicitSpecialization) { + 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. + 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 { + assert(getLangOptions().CPlusPlus); + + // 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<ClassTemplateDecl>(PrevDecl)) Kind = 2; + 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)) { + // 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<ClassTemplateDecl>(PrevDecl)) Kind = 2; + 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 (isa<TypedefDecl>(PrevDecl)) { + Diag(NameLoc, diag::err_tag_definition_of_typedef) + << Name + << cast<TypedefDecl>(PrevDecl)->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; + + 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, Loc, Name, KWLoc, + cast_or_null<EnumDecl>(PrevDecl)); + // If this is an undefined enum, warn. + if (TUK != TUK_Definition && !Invalid) { + unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum + : diag::ext_forward_ref_enum; + Diag(Loc, DK); + } + } 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 (getLangOptions().CPlusPlus) { + // FIXME: Look for a way to use RecordDecl for simple structs. + New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, + cast_or_null<CXXRecordDecl>(PrevDecl)); + + if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) + StdBadAlloc = cast<CXXRecordDecl>(New); + } else + New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, + cast_or_null<RecordDecl>(PrevDecl)); + } + + // Maybe add qualifier info. + if (SS.isNotEmpty()) { + if (SS.isSet()) { + NestedNameSpecifier *NNS + = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); + New->setQualifierInfo(NNS, SS.getRange()); + } + 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). + AddAlignmentAttributesForRecord(RD); + } + + // 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() && !getLangOptions().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. + if (TUK == TUK_Friend) + New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); + + // 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()->getLookupContext(); + DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); + 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); + } 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()->getLookupContext()->isTranslationUnit() && + II->isStr("FILE")) + Context.setFILEDecl(New); + + OwnedDecl = true; + return DeclPtrTy::make(New); +} + +void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { + AdjustDeclIfTemplate(TagD); + TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); + + // Enter the tag context. + PushDeclContext(S, Tag); +} + +void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, + SourceLocation LBraceLoc) { + AdjustDeclIfTemplate(TagD); + CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); + + FieldCollector->StartClass(); + + if (!Record->getIdentifier()) + return; + + // 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->getLocation(), + Record->getIdentifier(), + Record->getTagKeywordLoc(), + 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, DeclPtrTy TagD, + SourceLocation RBraceLoc) { + AdjustDeclIfTemplate(TagD); + TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); + Tag->setRBraceLoc(RBraceLoc); + + if (isa<CXXRecordDecl>(Tag)) + FieldCollector->FinishClass(); + + // Exit this scope of this tag's definition. + PopDeclContext(); + + // Notify the consumer that we've defined a tag. + Consumer.HandleTagDeclDefinition(Tag); +} + +void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { + AdjustDeclIfTemplate(TagD); + TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); + Tag->setInvalidDecl(); + + // 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. +bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, + QualType FieldTy, const 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->isIntegralType()) { + // Handle incomplete types with specific error. + if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) + return true; + 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(); + } + + // If the bit-width is type- or value-dependent, don't try to check + // it now. + if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) + return false; + + llvm::APSInt Value; + if (VerifyIntegerConstantExpression(BitWidth, &Value)) + return true; + + 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 (!getLangOptions().CPlusPlus) { + 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 false; +} + +/// ActOnField - Each field of a struct/union/class is passed into this in order +/// to create a FieldDecl object for it. +Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, + SourceLocation DeclStart, + Declarator &D, ExprTy *BitfieldWidth) { + FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), + DeclStart, D, static_cast<Expr*>(BitfieldWidth), + AS_public); + return DeclPtrTy::make(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, + AccessSpecifier AS) { + IdentifierInfo *II = D.getIdentifier(); + SourceLocation Loc = DeclStart; + if (II) Loc = D.getIdentifierLoc(); + + TypeSourceInfo *TInfo = 0; + QualType T = GetTypeForDeclarator(D, S, &TInfo); + if (getLangOptions().CPlusPlus) + CheckExtraCXXDefaultArguments(D); + + DiagnoseFunctionSpecifiers(D); + + if (D.getDeclSpec().isThreadSpecified()) + Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); + + NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, + ForRedeclaration); + + 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.getSourceRange().getBegin(); + FieldDecl *NewFD + = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, + AS, PrevDecl, &D); + + if (NewFD->isInvalidDecl()) + Record->setInvalidDecl(); + + 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, + 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() && + RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) + 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; + QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, + SizeIsNegative); + if (!FixedTy.isNull()) { + Diag(Loc, diag::warn_illegal_constant_array_size); + T = FixedTy; + } else { + if (SizeIsNegative) + Diag(Loc, diag::err_typecheck_negative_array_size); + 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 && + VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { + InvalidDecl = true; + DeleteExpr(BitWidth); + BitWidth = 0; + ZeroWidth = false; + } + + FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, + BitWidth, Mutable); + 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 && getLangOptions().CPlusPlus) { + CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); + + if (!T->isPODType()) + CXXRecord->setPOD(false); + if (!ZeroWidth) + CXXRecord->setEmpty(false); + + if (const RecordType *RT = EltTy->getAs<RecordType>()) { + CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); + + if (!RDecl->hasTrivialConstructor()) + CXXRecord->setHasTrivialConstructor(false); + if (!RDecl->hasTrivialCopyConstructor()) + CXXRecord->setHasTrivialCopyConstructor(false); + if (!RDecl->hasTrivialCopyAssignment()) + CXXRecord->setHasTrivialCopyAssignment(false); + if (!RDecl->hasTrivialDestructor()) + CXXRecord->setHasTrivialDestructor(false); + + // C++ 9.5p1: 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. + // TODO: C++0x alters this restriction significantly. + if (Record->isUnion()) { + // We check for copy constructors before constructors + // because otherwise we'll never get complaints about + // copy constructors. + + CXXSpecialMember member = CXXInvalid; + if (!RDecl->hasTrivialCopyConstructor()) + member = CXXCopyConstructor; + else if (!RDecl->hasTrivialConstructor()) + member = CXXConstructor; + else if (!RDecl->hasTrivialCopyAssignment()) + member = CXXCopyAssignment; + else if (!RDecl->hasTrivialDestructor()) + member = CXXDestructor; + + if (member != CXXInvalid) { + Diag(Loc, diag::err_illegal_union_member) << Name << member; + DiagnoseNontrivial(RT, member); + NewFD->setInvalidDecl(); + } + } + } + } + + // FIXME: We need to pass in the attributes given an AST + // representation, not a parser representation. + if (D) + // FIXME: What to pass instead of TUScope? + ProcessDeclAttributes(TUScope, NewFD, *D); + + if (T.isObjCGCWeak()) + Diag(Loc, diag::warn_attribute_weak_on_field); + + NewFD->setAccess(AS); + + // C++ [dcl.init.aggr]p1: + // An aggregate is an array or a class (clause 9) with [...] no + // private or protected non-static data members (clause 11). + // A POD must be an aggregate. + if (getLangOptions().CPlusPlus && + (AS == AS_private || AS == AS_protected)) { + CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); + CXXRecord->setAggregate(false); + CXXRecord->setPOD(false); + } + + return NewFD; +} + +/// DiagnoseNontrivial - Given that a class has a non-trivial +/// special member, figure out why. +void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { + QualType QT(T, 0U); + CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); + + // Check whether the member was user-declared. + switch (member) { + case CXXInvalid: + break; + + case CXXConstructor: + if (RD->hasUserDeclaredConstructor()) { + typedef CXXRecordDecl::ctor_iterator ctor_iter; + for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ + const FunctionDecl *body = 0; + ci->getBody(body); + if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { + SourceLocation CtorLoc = ci->getLocation(); + Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; + return; + } + } + + assert(0 && "found no user-declared constructors"); + return; + } + break; + + case CXXCopyConstructor: + if (RD->hasUserDeclaredCopyConstructor()) { + SourceLocation CtorLoc = + RD->getCopyConstructor(Context, 0)->getLocation(); + Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; + return; + } + break; + + case CXXCopyAssignment: + if (RD->hasUserDeclaredCopyAssignment()) { + // FIXME: this should use the location of the copy + // assignment, not the type. + SourceLocation TyLoc = RD->getSourceRange().getBegin(); + Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; + return; + } + break; + + case CXXDestructor: + if (RD->hasUserDeclaredDestructor()) { + SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); + Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; + return; + } + break; + } + + typedef CXXRecordDecl::base_class_iterator base_iter; + + // Virtual bases and members inhibit trivial copying/construction, + // but not trivial destruction. + if (member != CXXDestructor) { + // Check for virtual bases. vbases includes indirect virtual bases, + // so we just iterate through the direct bases. + for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) + if (bi->isVirtual()) { + SourceLocation BaseLoc = bi->getSourceRange().getBegin(); + Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; + return; + } + + // Check for virtual methods. + typedef CXXRecordDecl::method_iterator meth_iter; + for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; + ++mi) { + if (mi->isVirtual()) { + SourceLocation MLoc = mi->getSourceRange().getBegin(); + Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; + return; + } + } + } + + bool (CXXRecordDecl::*hasTrivial)() const; + switch (member) { + case CXXConstructor: + hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; + case CXXCopyConstructor: + hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; + case CXXCopyAssignment: + hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; + case CXXDestructor: + hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; + default: + assert(0 && "unexpected special member"); return; + } + + // Check for nontrivial bases (and recurse). + for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { + const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); + assert(BaseRT && "Don't know how to handle dependent bases"); + CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); + if (!(BaseRecTy->*hasTrivial)()) { + SourceLocation BaseLoc = bi->getSourceRange().getBegin(); + Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; + DiagnoseNontrivial(BaseRT, member); + return; + } + } + + // Check for nontrivial members (and recurse). + typedef RecordDecl::field_iterator field_iter; + for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; + ++fi) { + QualType EltTy = Context.getBaseElementType((*fi)->getType()); + if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { + CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); + + if (!(EltRD->*hasTrivial)()) { + SourceLocation FLoc = (*fi)->getLocation(); + Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; + DiagnoseNontrivial(EltRT, member); + return; + } + } + } + + assert(0 && "found no explanation for non-trivial member"); +} + +/// TranslateIvarVisibility - Translate visibility from a token ID to an +/// AST enum value. +static ObjCIvarDecl::AccessControl +TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { + switch (ivarVisibility) { + default: assert(0 && "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. +Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, + SourceLocation DeclStart, + DeclPtrTy IntfDecl, + Declarator &D, ExprTy *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 = 0; + QualType T = GetTypeForDeclarator(D, S, &TInfo); + + if (BitWidth) { + // 6.7.2.1p3, 6.7.2.1p4 + if (VerifyBitField(Loc, II, T, BitWidth)) { + D.setInvalidType(); + DeleteExpr(BitWidth); + BitWidth = 0; + } + } 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 = IntfDecl.getAs<ObjCContainerDecl>(); + ObjCContainerDecl *EnclosingContext; + if (ObjCImplementationDecl *IMPDecl = + dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { + // Case of ivar declared in an implementation. Context is that of its class. + EnclosingContext = IMPDecl->getClassInterface(); + assert(EnclosingContext && "Implementation has no class interface!"); + } else { + if (ObjCCategoryDecl *CDecl = + dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { + if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { + Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); + return DeclPtrTy(); + } + } + EnclosingContext = EnclosingDecl; + } + + // Construct the decl. + ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, + EnclosingContext, 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(); + + if (II) { + // FIXME: When interfaces are DeclContexts, we'll need to add + // these to the interface. + S->AddDecl(DeclPtrTy::make(NewID)); + IdResolver.AddDecl(NewID); + } + + return DeclPtrTy::make(NewID); +} + +void Sema::ActOnFields(Scope* S, + SourceLocation RecLoc, DeclPtrTy RecDecl, + DeclPtrTy *Fields, unsigned NumFields, + SourceLocation LBrac, SourceLocation RBrac, + AttributeList *Attr) { + Decl *EnclosingDecl = RecDecl.getAs<Decl>(); + assert(EnclosingDecl && "missing record or interface decl"); + + // If the decl this is being inserted into is invalid, then it may be a + // redeclaration or some other bogus case. Don't try to add fields to it. + if (EnclosingDecl->isInvalidDecl()) { + // FIXME: Deallocate fields? + return; + } + + + // Verify that all the fields are okay. + unsigned NumNamedMembers = 0; + llvm::SmallVector<FieldDecl*, 32> RecFields; + + RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); + for (unsigned i = 0; i != NumFields; ++i) { + FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); + + // Get the type for the field. + 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() && i == NumFields - 1 && + Record && Record->isStruct()) { + // Flexible array member. + if (NumNamedMembers < 1) { + Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) + << FD->getDeclName(); + FD->setInvalidDecl(); + EnclosingDecl->setInvalidDecl(); + continue; + } + if (!FD->getType()->isDependentType() && + !Context.getBaseElementType(FD->getType())->isPODType()) { + 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 != NumFields-1) + 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 (Record && FDTTy->getDecl()->hasObjectMember()) + Record->setHasObjectMember(true); + } else if (FDTy->isObjCObjectType()) { + /// A field cannot be an Objective-c object + Diag(FD->getLocation(), diag::err_statically_allocated_object); + FD->setInvalidDecl(); + EnclosingDecl->setInvalidDecl(); + continue; + } else if (getLangOptions().ObjC1 && + getLangOptions().getGCMode() != LangOptions::NonGC && + Record && + (FD->getType()->isObjCObjectPointerType() || + FD->getType().isObjCGCStrong())) + Record->setHasObjectMember(true); + // Keep track of the number of named members. + if (FD->getIdentifier()) + ++NumNamedMembers; + } + + // Okay, we successfully defined 'Record'. + if (Record) { + Record->completeDefinition(); + } else { + ObjCIvarDecl **ClsFields = + reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); + if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { + ID->setLocEnd(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); + } 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. + for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { + ClsFields[i]->setLexicalDeclContext(CDecl); + CDecl->addDecl(ClsFields[i]); + } + } + } + + 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() && "Integral type required!"); + unsigned BitWidth = Context.getIntWidth(T); + + if (Value.isUnsigned() || Value.isNonNegative()) + 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() && "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->isSignedIntegerType()? 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, + ExprArg val) { + Expr *Val = (Expr *)val.get(); + + unsigned IntWidth = Context.Target.getIntWidth(); + llvm::APSInt EnumVal(IntWidth); + QualType EltTy; + if (Val) { + if (Enum->isDependentType() || Val->isTypeDependent()) + EltTy = Context.DependentTy; + else { + // C99 6.7.2.2p2: Make sure we have an integer constant expression. + SourceLocation ExpLoc; + if (!Val->isValueDependent() && + VerifyIntegerConstantExpression(Val, &EnumVal)) { + Val = 0; + } else { + if (!getLangOptions().CPlusPlus) { + // 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'. + ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); + + if (Val != val.get()) { + val.release(); + val = Val; + } + } + } + + // 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 an initializer is specified for an enumerator, the + // initializing value has the same type as the expression. + 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. + 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()) { + // There is no integral type larger enough to represent this + // value. Complain, then allow the value to wrap around. + EnumVal = LastEnumConst->getInitVal(); + EnumVal.zext(EnumVal.getBitWidth() * 2); + 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->isSignedIntegerType()); + 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 (!getLangOptions().CPlusPlus && !T.isNull()) + Diag(IdLoc, diag::warn_enum_value_overflow); + } else if (!getLangOptions().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.zextOrTrunc(Context.getIntWidth(EltTy)); + EnumVal.setIsSigned(EltTy->isSignedIntegerType()); + } + + val.release(); + return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, + Val, EnumVal); +} + + +Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, + DeclPtrTy lastEnumConst, + SourceLocation IdLoc, + IdentifierInfo *Id, + SourceLocation EqualLoc, ExprTy *val) { + EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); + EnumConstantDecl *LastEnumConst = + cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); + Expr *Val = static_cast<Expr*>(val); + + // 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((getLangOptions().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); + if (Val) Val->Destroy(Context); + return DeclPtrTy(); + } + } + + EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, + IdLoc, Id, Owned(Val)); + + // Register this decl in the current scope stack. + if (New) { + New->setAccess(TheEnumDecl->getAccess()); + PushOnScopeChains(New, S); + } + + return DeclPtrTy::make(New); +} + +void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, + SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, + DeclPtrTy *Elements, unsigned NumElements, + Scope *S, AttributeList *Attr) { + EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); + QualType EnumType = Context.getTypeDeclType(Enum); + + if (Attr) + ProcessDeclAttributeList(S, Enum, Attr); + + if (Enum->isDependentType()) { + for (unsigned i = 0; i != NumElements; ++i) { + EnumConstantDecl *ECD = + cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); + 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.Target.getIntWidth(); + unsigned CharWidth = Context.Target.getCharWidth(); + unsigned ShortWidth = Context.Target.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; i != NumElements; ++i) { + EnumConstantDecl *ECD = + cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); + 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. + // FIXME: Support -fshort-enums. + 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; + + 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.Target.getLongWidth(); + + if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { + BestType = Context.LongTy; + } else { + BestWidth = Context.Target.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 || !getLangOptions().CPlusPlus) + ? Context.UnsignedIntTy : Context.IntTy; + } else if (NumPositiveBits <= + (BestWidth = Context.Target.getLongWidth())) { + BestType = Context.UnsignedLongTy; + BestPromotionType + = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) + ? Context.UnsignedLongTy : Context.LongTy; + } else { + BestWidth = Context.Target.getLongLongWidth(); + assert(NumPositiveBits <= BestWidth && + "How could an initializer get larger than ULL?"); + BestType = Context.UnsignedLongLongTy; + BestPromotionType + = (NumPositiveBits == BestWidth || !getLangOptions().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; i != NumElements; ++i) { + EnumConstantDecl *ECD = + cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); + 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 (!getLangOptions().CPlusPlus && + isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { + NewTy = Context.IntTy; + NewWidth = IntWidth; + NewSign = true; + } else if (ECD->getType() == BestType) { + // Already the right type! + if (getLangOptions().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->isSignedIntegerType(); + } + + // Adjust the APSInt value. + InitVal.extOrTrunc(NewWidth); + InitVal.setIsSigned(NewSign); + ECD->setInitVal(InitVal); + + // Adjust the Expr initializer and type. + if (ECD->getInitExpr()) + ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, + CastExpr::CK_IntegralCast, + ECD->getInitExpr(), + CXXBaseSpecifierArray(), + /*isLvalue=*/false)); + if (getLangOptions().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); +} + +Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, + ExprArg expr) { + StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); + + FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, + Loc, AsmString); + CurContext->addDecl(New); + return DeclPtrTy::make(New); +} + +void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, + SourceLocation PragmaLoc, + SourceLocation NameLoc) { + Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); + + if (PrevDecl) { + PrevDecl->addAttr(::new (Context) WeakAttr()); + } 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)); + } +} |
