//===--- SemaType.cpp - Semantic Analysis for Types -----------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements type-related semantic analysis. // //===----------------------------------------------------------------------===// #include "Sema.h" #include "clang/AST/ASTContext.h" #include "clang/AST/DeclObjC.h" #include "clang/AST/DeclTemplate.h" #include "clang/AST/Expr.h" #include "clang/Parse/DeclSpec.h" using namespace clang; /// \brief Perform adjustment on the parameter type of a function. /// /// This routine adjusts the given parameter type @p T to the actual /// parameter type used by semantic analysis (C99 6.7.5.3p[7,8], /// C++ [dcl.fct]p3). The adjusted parameter type is returned. QualType Sema::adjustParameterType(QualType T) { // C99 6.7.5.3p7: if (T->isArrayType()) { // C99 6.7.5.3p7: // A declaration of a parameter as "array of type" shall be // adjusted to "qualified pointer to type", where the type // qualifiers (if any) are those specified within the [ and ] of // the array type derivation. return Context.getArrayDecayedType(T); } else if (T->isFunctionType()) // C99 6.7.5.3p8: // A declaration of a parameter as "function returning type" // shall be adjusted to "pointer to function returning type", as // in 6.3.2.1. return Context.getPointerType(T); return T; } /// \brief Convert the specified declspec to the appropriate type /// object. /// \param DS the declaration specifiers /// \param DeclLoc The location of the declarator identifier or invalid if none. /// \returns The type described by the declaration specifiers. This function /// never returns null. QualType Sema::ConvertDeclSpecToType(const DeclSpec &DS, SourceLocation DeclLoc, bool &isInvalid) { // FIXME: Should move the logic from DeclSpec::Finish to here for validity // checking. QualType Result; switch (DS.getTypeSpecType()) { case DeclSpec::TST_void: Result = Context.VoidTy; break; case DeclSpec::TST_char: if (DS.getTypeSpecSign() == DeclSpec::TSS_unspecified) Result = Context.CharTy; else if (DS.getTypeSpecSign() == DeclSpec::TSS_signed) Result = Context.SignedCharTy; else { assert(DS.getTypeSpecSign() == DeclSpec::TSS_unsigned && "Unknown TSS value"); Result = Context.UnsignedCharTy; } break; case DeclSpec::TST_wchar: if (DS.getTypeSpecSign() == DeclSpec::TSS_unspecified) Result = Context.WCharTy; else if (DS.getTypeSpecSign() == DeclSpec::TSS_signed) { Diag(DS.getTypeSpecSignLoc(), diag::ext_invalid_sign_spec) << DS.getSpecifierName(DS.getTypeSpecType()); Result = Context.getSignedWCharType(); } else { assert(DS.getTypeSpecSign() == DeclSpec::TSS_unsigned && "Unknown TSS value"); Diag(DS.getTypeSpecSignLoc(), diag::ext_invalid_sign_spec) << DS.getSpecifierName(DS.getTypeSpecType()); Result = Context.getUnsignedWCharType(); } break; case DeclSpec::TST_unspecified: // "" is an objc qualified ID with a missing id. if (DeclSpec::ProtocolQualifierListTy PQ = DS.getProtocolQualifiers()) { Result = Context.getObjCQualifiedIdType((ObjCProtocolDecl**)PQ, DS.getNumProtocolQualifiers()); break; } // Unspecified typespec defaults to int in C90. However, the C90 grammar // [C90 6.5] only allows a decl-spec if there was *some* type-specifier, // type-qualifier, or storage-class-specifier. If not, emit an extwarn. // Note that the one exception to this is function definitions, which are // allowed to be completely missing a declspec. This is handled in the // parser already though by it pretending to have seen an 'int' in this // case. if (getLangOptions().ImplicitInt) { // In C89 mode, we only warn if there is a completely missing declspec // when one is not allowed. if (DS.isEmpty()) { if (DeclLoc.isInvalid()) DeclLoc = DS.getSourceRange().getBegin(); Diag(DeclLoc, diag::warn_missing_declspec) << DS.getSourceRange() << CodeModificationHint::CreateInsertion(DS.getSourceRange().getBegin(), "int"); } } else if (!DS.hasTypeSpecifier()) { // C99 and C++ require a type specifier. For example, C99 6.7.2p2 says: // "At least one type specifier shall be given in the declaration // specifiers in each declaration, and in the specifier-qualifier list in // each struct declaration and type name." // FIXME: Does Microsoft really have the implicit int extension in C++? if (DeclLoc.isInvalid()) DeclLoc = DS.getSourceRange().getBegin(); if (getLangOptions().CPlusPlus && !getLangOptions().Microsoft) Diag(DeclLoc, diag::err_missing_type_specifier) << DS.getSourceRange(); else Diag(DeclLoc, diag::warn_missing_type_specifier) << DS.getSourceRange(); // FIXME: If we could guarantee that the result would be well-formed, it // would be useful to have a code insertion hint here. However, after // emitting this warning/error, we often emit other errors. } // FALL THROUGH. case DeclSpec::TST_int: { if (DS.getTypeSpecSign() != DeclSpec::TSS_unsigned) { switch (DS.getTypeSpecWidth()) { case DeclSpec::TSW_unspecified: Result = Context.IntTy; break; case DeclSpec::TSW_short: Result = Context.ShortTy; break; case DeclSpec::TSW_long: Result = Context.LongTy; break; case DeclSpec::TSW_longlong: Result = Context.LongLongTy; break; } } else { switch (DS.getTypeSpecWidth()) { case DeclSpec::TSW_unspecified: Result = Context.UnsignedIntTy; break; case DeclSpec::TSW_short: Result = Context.UnsignedShortTy; break; case DeclSpec::TSW_long: Result = Context.UnsignedLongTy; break; case DeclSpec::TSW_longlong: Result =Context.UnsignedLongLongTy; break; } } break; } case DeclSpec::TST_float: Result = Context.FloatTy; break; case DeclSpec::TST_double: if (DS.getTypeSpecWidth() == DeclSpec::TSW_long) Result = Context.LongDoubleTy; else Result = Context.DoubleTy; break; case DeclSpec::TST_bool: Result = Context.BoolTy; break; // _Bool or bool case DeclSpec::TST_decimal32: // _Decimal32 case DeclSpec::TST_decimal64: // _Decimal64 case DeclSpec::TST_decimal128: // _Decimal128 Diag(DS.getTypeSpecTypeLoc(), diag::err_decimal_unsupported); Result = Context.IntTy; isInvalid = true; break; case DeclSpec::TST_class: case DeclSpec::TST_enum: case DeclSpec::TST_union: case DeclSpec::TST_struct: { Decl *D = static_cast(DS.getTypeRep()); assert(D && "Didn't get a decl for a class/enum/union/struct?"); assert(DS.getTypeSpecWidth() == 0 && DS.getTypeSpecComplex() == 0 && DS.getTypeSpecSign() == 0 && "Can't handle qualifiers on typedef names yet!"); // TypeQuals handled by caller. Result = Context.getTypeDeclType(cast(D)); if (D->isInvalidDecl()) isInvalid = true; break; } case DeclSpec::TST_typename: { assert(DS.getTypeSpecWidth() == 0 && DS.getTypeSpecComplex() == 0 && DS.getTypeSpecSign() == 0 && "Can't handle qualifiers on typedef names yet!"); Result = QualType::getFromOpaquePtr(DS.getTypeRep()); if (DeclSpec::ProtocolQualifierListTy PQ = DS.getProtocolQualifiers()) { // FIXME: Adding a TST_objcInterface clause doesn't seem ideal, so we have // this "hack" for now... if (const ObjCInterfaceType *Interface = Result->getAsObjCInterfaceType()) Result = Context.getObjCQualifiedInterfaceType(Interface->getDecl(), (ObjCProtocolDecl**)PQ, DS.getNumProtocolQualifiers()); else if (Result == Context.getObjCIdType()) // id Result = Context.getObjCQualifiedIdType((ObjCProtocolDecl**)PQ, DS.getNumProtocolQualifiers()); else if (Result == Context.getObjCClassType()) { if (DeclLoc.isInvalid()) DeclLoc = DS.getSourceRange().getBegin(); // Class Diag(DeclLoc, diag::err_qualified_class_unsupported) << DS.getSourceRange(); } else { if (DeclLoc.isInvalid()) DeclLoc = DS.getSourceRange().getBegin(); Diag(DeclLoc, diag::err_invalid_protocol_qualifiers) << DS.getSourceRange(); isInvalid = true; } } // If this is a reference to an invalid typedef, propagate the invalidity. if (TypedefType *TDT = dyn_cast(Result)) if (TDT->getDecl()->isInvalidDecl()) isInvalid = true; // TypeQuals handled by caller. break; } case DeclSpec::TST_typeofType: Result = QualType::getFromOpaquePtr(DS.getTypeRep()); assert(!Result.isNull() && "Didn't get a type for typeof?"); // TypeQuals handled by caller. Result = Context.getTypeOfType(Result); break; case DeclSpec::TST_typeofExpr: { Expr *E = static_cast(DS.getTypeRep()); assert(E && "Didn't get an expression for typeof?"); // TypeQuals handled by caller. Result = Context.getTypeOfExprType(E); break; } case DeclSpec::TST_error: Result = Context.IntTy; isInvalid = true; break; } // Handle complex types. if (DS.getTypeSpecComplex() == DeclSpec::TSC_complex) { if (getLangOptions().Freestanding) Diag(DS.getTypeSpecComplexLoc(), diag::ext_freestanding_complex); Result = Context.getComplexType(Result); } assert(DS.getTypeSpecComplex() != DeclSpec::TSC_imaginary && "FIXME: imaginary types not supported yet!"); // See if there are any attributes on the declspec that apply to the type (as // opposed to the decl). if (const AttributeList *AL = DS.getAttributes()) ProcessTypeAttributeList(Result, AL); // Apply const/volatile/restrict qualifiers to T. 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." C++ also allows // restrict-qualified references. if (TypeQuals & QualType::Restrict) { if (Result->isPointerType() || Result->isReferenceType()) { QualType EltTy = Result->isPointerType() ? Result->getAsPointerType()->getPointeeType() : Result->getAsReferenceType()->getPointeeType(); // If we have a pointer or reference, the pointee must have an object // incomplete type. if (!EltTy->isIncompleteOrObjectType()) { Diag(DS.getRestrictSpecLoc(), diag::err_typecheck_invalid_restrict_invalid_pointee) << EltTy << DS.getSourceRange(); TypeQuals &= ~QualType::Restrict; // Remove the restrict qualifier. } } else { Diag(DS.getRestrictSpecLoc(), diag::err_typecheck_invalid_restrict_not_pointer) << Result << DS.getSourceRange(); TypeQuals &= ~QualType::Restrict; // Remove the restrict qualifier. } } // Warn about CV qualifiers on functions: C99 6.7.3p8: "If the specification // of a function type includes any type qualifiers, the behavior is // undefined." if (Result->isFunctionType() && TypeQuals) { // Get some location to point at, either the C or V location. SourceLocation Loc; if (TypeQuals & QualType::Const) Loc = DS.getConstSpecLoc(); else { assert((TypeQuals & QualType::Volatile) && "Has CV quals but not C or V?"); Loc = DS.getVolatileSpecLoc(); } Diag(Loc, diag::warn_typecheck_function_qualifiers) << Result << DS.getSourceRange(); } // C++ [dcl.ref]p1: // Cv-qualified references are ill-formed except when the // cv-qualifiers are introduced through the use of a typedef // (7.1.3) or of a template type argument (14.3), in which // case the cv-qualifiers are ignored. // FIXME: Shouldn't we be checking SCS_typedef here? if (DS.getTypeSpecType() == DeclSpec::TST_typename && TypeQuals && Result->isReferenceType()) { TypeQuals &= ~QualType::Const; TypeQuals &= ~QualType::Volatile; } Result = Result.getQualifiedType(TypeQuals); } return Result; } static std::string getPrintableNameForEntity(DeclarationName Entity) { if (Entity) return Entity.getAsString(); return "type name"; } /// \brief Build a pointer type. /// /// \param T The type to which we'll be building a pointer. /// /// \param Quals The cvr-qualifiers to be applied to the pointer type. /// /// \param Loc The location of the entity whose type involves this /// pointer type or, if there is no such entity, the location of the /// type that will have pointer type. /// /// \param Entity The name of the entity that involves the pointer /// type, if known. /// /// \returns A suitable pointer type, if there are no /// errors. Otherwise, returns a NULL type. QualType Sema::BuildPointerType(QualType T, unsigned Quals, SourceLocation Loc, DeclarationName Entity) { if (T->isReferenceType()) { // C++ 8.3.2p4: There shall be no ... pointers to references ... Diag(Loc, diag::err_illegal_decl_pointer_to_reference) << getPrintableNameForEntity(Entity); return QualType(); } // Enforce C99 6.7.3p2: "Types other than pointer types derived from // object or incomplete types shall not be restrict-qualified." if ((Quals & QualType::Restrict) && !T->isIncompleteOrObjectType()) { Diag(Loc, diag::err_typecheck_invalid_restrict_invalid_pointee) << T; Quals &= ~QualType::Restrict; } // Build the pointer type. return Context.getPointerType(T).getQualifiedType(Quals); } /// \brief Build a reference type. /// /// \param T The type to which we'll be building a reference. /// /// \param Quals The cvr-qualifiers to be applied to the reference type. /// /// \param Loc The location of the entity whose type involves this /// reference type or, if there is no such entity, the location of the /// type that will have reference type. /// /// \param Entity The name of the entity that involves the reference /// type, if known. /// /// \returns A suitable reference type, if there are no /// errors. Otherwise, returns a NULL type. QualType Sema::BuildReferenceType(QualType T, bool LValueRef, unsigned Quals, SourceLocation Loc, DeclarationName Entity) { if (LValueRef) { if (const RValueReferenceType *R = T->getAsRValueReferenceType()) { // C++0x [dcl.typedef]p9: If a typedef TD names a type that is a // reference to a type T, and attempt to create the type "lvalue // reference to cv TD" creates the type "lvalue reference to T". // We use the qualifiers (restrict or none) of the original reference, // not the new ones. This is consistent with GCC. return Context.getLValueReferenceType(R->getPointeeType()). getQualifiedType(T.getCVRQualifiers()); } } if (T->isReferenceType()) { // C++ [dcl.ref]p4: There shall be no references to references. // // According to C++ DR 106, references to references are only // diagnosed when they are written directly (e.g., "int & &"), // but not when they happen via a typedef: // // typedef int& intref; // typedef intref& intref2; // // Parser::ParserDeclaratorInternal diagnoses the case where // references are written directly; here, we handle the // collapsing of references-to-references as described in C++ // DR 106 and amended by C++ DR 540. return T; } // C++ [dcl.ref]p1: // A declarator that specifies the type “reference to cv void” // is ill-formed. if (T->isVoidType()) { Diag(Loc, diag::err_reference_to_void); return QualType(); } // Enforce C99 6.7.3p2: "Types other than pointer types derived from // object or incomplete types shall not be restrict-qualified." if ((Quals & QualType::Restrict) && !T->isIncompleteOrObjectType()) { Diag(Loc, diag::err_typecheck_invalid_restrict_invalid_pointee) << T; Quals &= ~QualType::Restrict; } // C++ [dcl.ref]p1: // [...] Cv-qualified references are ill-formed except when the // cv-qualifiers are introduced through the use of a typedef // (7.1.3) or of a template type argument (14.3), in which case // the cv-qualifiers are ignored. // // We diagnose extraneous cv-qualifiers for the non-typedef, // non-template type argument case within the parser. Here, we just // ignore any extraneous cv-qualifiers. Quals &= ~QualType::Const; Quals &= ~QualType::Volatile; // Handle restrict on references. if (LValueRef) return Context.getLValueReferenceType(T).getQualifiedType(Quals); return Context.getRValueReferenceType(T).getQualifiedType(Quals); } /// \brief Build an array type. /// /// \param T The type of each element in the array. /// /// \param ASM C99 array size modifier (e.g., '*', 'static'). /// /// \param ArraySize Expression describing the size of the array. /// /// \param Quals The cvr-qualifiers to be applied to the array's /// element type. /// /// \param Loc The location of the entity whose type involves this /// array type or, if there is no such entity, the location of the /// type that will have array type. /// /// \param Entity The name of the entity that involves the array /// type, if known. /// /// \returns A suitable array type, if there are no errors. Otherwise, /// returns a NULL type. QualType Sema::BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM, Expr *ArraySize, unsigned Quals, SourceLocation Loc, DeclarationName Entity) { // C99 6.7.5.2p1: If the element type is an incomplete or function type, // reject it (e.g. void ary[7], struct foo ary[7], void ary[7]()) if (RequireCompleteType(Loc, T, diag::err_illegal_decl_array_incomplete_type)) return QualType(); if (T->isFunctionType()) { Diag(Loc, diag::err_illegal_decl_array_of_functions) << getPrintableNameForEntity(Entity); return QualType(); } // C++ 8.3.2p4: There shall be no ... arrays of references ... if (T->isReferenceType()) { Diag(Loc, diag::err_illegal_decl_array_of_references) << getPrintableNameForEntity(Entity); return QualType(); } if (const RecordType *EltTy = T->getAsRecordType()) { // If the element type is a struct or union that contains a variadic // array, accept it as a GNU extension: C99 6.7.2.1p2. if (EltTy->getDecl()->hasFlexibleArrayMember()) Diag(Loc, diag::ext_flexible_array_in_array) << T; } else if (T->isObjCInterfaceType()) { Diag(Loc, diag::err_objc_array_of_interfaces) << T; return QualType(); } // C99 6.7.5.2p1: The size expression shall have integer type. if (ArraySize && !ArraySize->isTypeDependent() && !ArraySize->getType()->isIntegerType()) { Diag(ArraySize->getLocStart(), diag::err_array_size_non_int) << ArraySize->getType() << ArraySize->getSourceRange(); ArraySize->Destroy(Context); return QualType(); } llvm::APSInt ConstVal(32); if (!ArraySize) { if (ASM == ArrayType::Star) T = Context.getVariableArrayType(T, 0, ASM, Quals); else T = Context.getIncompleteArrayType(T, ASM, Quals); } else if (ArraySize->isValueDependent()) { T = Context.getDependentSizedArrayType(T, ArraySize, ASM, Quals); } else if (!ArraySize->isIntegerConstantExpr(ConstVal, Context) || (!T->isDependentType() && !T->isConstantSizeType())) { // Per C99, a variable array is an array with either a non-constant // size or an element type that has a non-constant-size T = Context.getVariableArrayType(T, ArraySize, ASM, Quals); } else { // C99 6.7.5.2p1: If the expression is a constant expression, it shall // have a value greater than zero. if (ConstVal.isSigned()) { if (ConstVal.isNegative()) { Diag(ArraySize->getLocStart(), diag::err_typecheck_negative_array_size) << ArraySize->getSourceRange(); return QualType(); } else if (ConstVal == 0) { // GCC accepts zero sized static arrays. Diag(ArraySize->getLocStart(), diag::ext_typecheck_zero_array_size) << ArraySize->getSourceRange(); } } T = Context.getConstantArrayType(T, ConstVal, ASM, Quals); } // If this is not C99, extwarn about VLA's and C99 array size modifiers. if (!getLangOptions().C99) { if (ArraySize && !ArraySize->isTypeDependent() && !ArraySize->isValueDependent() && !ArraySize->isIntegerConstantExpr(Context)) Diag(Loc, diag::ext_vla); else if (ASM != ArrayType::Normal || Quals != 0) Diag(Loc, diag::ext_c99_array_usage); } return T; } /// \brief Build a function type. /// /// This routine checks the function type according to C++ rules and /// under the assumption that the result type and parameter types have /// just been instantiated from a template. It therefore duplicates /// some of the behavior of GetTypeForDeclarator, but in a much /// simpler form that is only suitable for this narrow use case. /// /// \param T The return type of the function. /// /// \param ParamTypes The parameter types of the function. This array /// will be modified to account for adjustments to the types of the /// function parameters. /// /// \param NumParamTypes The number of parameter types in ParamTypes. /// /// \param Variadic Whether this is a variadic function type. /// /// \param Quals The cvr-qualifiers to be applied to the function type. /// /// \param Loc The location of the entity whose type involves this /// function type or, if there is no such entity, the location of the /// type that will have function type. /// /// \param Entity The name of the entity that involves the function /// type, if known. /// /// \returns A suitable function type, if there are no /// errors. Otherwise, returns a NULL type. QualType Sema::BuildFunctionType(QualType T, QualType *ParamTypes, unsigned NumParamTypes, bool Variadic, unsigned Quals, SourceLocation Loc, DeclarationName Entity) { if (T->isArrayType() || T->isFunctionType()) { Diag(Loc, diag::err_func_returning_array_function) << T; return QualType(); } bool Invalid = false; for (unsigned Idx = 0; Idx < NumParamTypes; ++Idx) { QualType ParamType = adjustParameterType(ParamTypes[Idx]); if (ParamType->isVoidType()) { Diag(Loc, diag::err_param_with_void_type); Invalid = true; } ParamTypes[Idx] = ParamType; } if (Invalid) return QualType(); return Context.getFunctionType(T, ParamTypes, NumParamTypes, Variadic, Quals); } /// GetTypeForDeclarator - Convert the type for the specified /// declarator to Type instances. Skip the outermost Skip type /// objects. /// /// If OwnedDecl is non-NULL, and this declarator's decl-specifier-seq /// owns the declaration of a type (e.g., the definition of a struct /// type), then *OwnedDecl will receive the owned declaration. QualType Sema::GetTypeForDeclarator(Declarator &D, Scope *S, unsigned Skip, TagDecl **OwnedDecl) { bool OmittedReturnType = false; if (D.getContext() == Declarator::BlockLiteralContext && Skip == 0 && !D.getDeclSpec().hasTypeSpecifier() && (D.getNumTypeObjects() == 0 || (D.getNumTypeObjects() == 1 && D.getTypeObject(0).Kind == DeclaratorChunk::Function))) OmittedReturnType = true; // long long is a C99 feature. if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && D.getDeclSpec().getTypeSpecWidth() == DeclSpec::TSW_longlong) Diag(D.getDeclSpec().getTypeSpecWidthLoc(), diag::ext_longlong); // Determine the type of the declarator. Not all forms of declarator // have a type. QualType T; switch (D.getKind()) { case Declarator::DK_Abstract: case Declarator::DK_Normal: case Declarator::DK_Operator: { const DeclSpec &DS = D.getDeclSpec(); if (OmittedReturnType) { // We default to a dependent type initially. Can be modified by // the first return statement. T = Context.DependentTy; } else { bool isInvalid = false; T = ConvertDeclSpecToType(DS, D.getIdentifierLoc(), isInvalid); if (isInvalid) D.setInvalidType(true); else if (OwnedDecl && DS.isTypeSpecOwned()) *OwnedDecl = cast((Decl *)DS.getTypeRep()); } break; } case Declarator::DK_Constructor: case Declarator::DK_Destructor: case Declarator::DK_Conversion: // Constructors and destructors don't have return types. Use // "void" instead. Conversion operators will check their return // types separately. T = Context.VoidTy; break; } // The name we're declaring, if any. DeclarationName Name; if (D.getIdentifier()) Name = D.getIdentifier(); // Walk the DeclTypeInfo, building the recursive type as we go. // DeclTypeInfos are ordered from the identifier out, which is // opposite of what we want :). for (unsigned i = Skip, e = D.getNumTypeObjects(); i != e; ++i) { DeclaratorChunk &DeclType = D.getTypeObject(e-i-1+Skip); switch (DeclType.Kind) { default: assert(0 && "Unknown decltype!"); case DeclaratorChunk::BlockPointer: // If blocks are disabled, emit an error. if (!LangOpts.Blocks) Diag(DeclType.Loc, diag::err_blocks_disable); if (!T.getTypePtr()->isFunctionType()) Diag(D.getIdentifierLoc(), diag::err_nonfunction_block_type); else T = (Context.getBlockPointerType(T) .getQualifiedType(DeclType.Cls.TypeQuals)); break; case DeclaratorChunk::Pointer: // Verify that we're not building a pointer to pointer to function with // exception specification. if (getLangOptions().CPlusPlus && CheckDistantExceptionSpec(T)) { Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec); D.setInvalidType(true); // Build the type anyway. } T = BuildPointerType(T, DeclType.Ptr.TypeQuals, DeclType.Loc, Name); break; case DeclaratorChunk::Reference: // Verify that we're not building a reference to pointer to function with // exception specification. if (getLangOptions().CPlusPlus && CheckDistantExceptionSpec(T)) { Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec); D.setInvalidType(true); // Build the type anyway. } T = BuildReferenceType(T, DeclType.Ref.LValueRef, DeclType.Ref.HasRestrict ? QualType::Restrict : 0, DeclType.Loc, Name); break; case DeclaratorChunk::Array: { // Verify that we're not building an array of pointers to function with // exception specification. if (getLangOptions().CPlusPlus && CheckDistantExceptionSpec(T)) { Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec); D.setInvalidType(true); // Build the type anyway. } DeclaratorChunk::ArrayTypeInfo &ATI = DeclType.Arr; Expr *ArraySize = static_cast(ATI.NumElts); ArrayType::ArraySizeModifier ASM; if (ATI.isStar) ASM = ArrayType::Star; else if (ATI.hasStatic) ASM = ArrayType::Static; else ASM = ArrayType::Normal; if (ASM == ArrayType::Star && D.getContext() != Declarator::PrototypeContext) { // FIXME: This check isn't quite right: it allows star in prototypes // for function definitions, and disallows some edge cases detailed // in http://gcc.gnu.org/ml/gcc-patches/2009-02/msg00133.html Diag(DeclType.Loc, diag::err_array_star_outside_prototype); ASM = ArrayType::Normal; D.setInvalidType(true); } T = BuildArrayType(T, ASM, ArraySize, ATI.TypeQuals, DeclType.Loc, Name); break; } case DeclaratorChunk::Function: { // If the function declarator has a prototype (i.e. it is not () and // does not have a K&R-style identifier list), then the arguments are part // of the type, otherwise the argument list is (). const DeclaratorChunk::FunctionTypeInfo &FTI = DeclType.Fun; // C99 6.7.5.3p1: The return type may not be a function or array type. if (T->isArrayType() || T->isFunctionType()) { Diag(DeclType.Loc, diag::err_func_returning_array_function) << T; T = Context.IntTy; D.setInvalidType(true); } if (getLangOptions().CPlusPlus && D.getDeclSpec().isTypeSpecOwned()) { // C++ [dcl.fct]p6: // Types shall not be defined in return or parameter types. TagDecl *Tag = cast((Decl *)D.getDeclSpec().getTypeRep()); if (Tag->isDefinition()) Diag(Tag->getLocation(), diag::err_type_defined_in_result_type) << Context.getTypeDeclType(Tag); } // Exception specs are not allowed in typedefs. Complain, but add it // anyway. if (FTI.hasExceptionSpec && D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) Diag(FTI.getThrowLoc(), diag::err_exception_spec_in_typedef); if (FTI.NumArgs == 0) { if (getLangOptions().CPlusPlus) { // C++ 8.3.5p2: If the parameter-declaration-clause is empty, the // function takes no arguments. llvm::SmallVector Exceptions; Exceptions.reserve(FTI.NumExceptions); for(unsigned ei = 0, ee = FTI.NumExceptions; ei != ee; ++ei) { QualType ET = QualType::getFromOpaquePtr(FTI.Exceptions[ei].Ty); // Check that the type is valid for an exception spec, and drop it // if not. if (!CheckSpecifiedExceptionType(ET, FTI.Exceptions[ei].Range)) Exceptions.push_back(ET); } T = Context.getFunctionType(T, NULL, 0, FTI.isVariadic, FTI.TypeQuals, FTI.hasExceptionSpec, FTI.hasAnyExceptionSpec, Exceptions.size(), Exceptions.data()); } else if (FTI.isVariadic) { // We allow a zero-parameter variadic function in C if the // function is marked with the "overloadable" // attribute. Scan for this attribute now. bool Overloadable = false; for (const AttributeList *Attrs = D.getAttributes(); Attrs; Attrs = Attrs->getNext()) { if (Attrs->getKind() == AttributeList::AT_overloadable) { Overloadable = true; break; } } if (!Overloadable) Diag(FTI.getEllipsisLoc(), diag::err_ellipsis_first_arg); T = Context.getFunctionType(T, NULL, 0, FTI.isVariadic, 0); } else { // Simple void foo(), where the incoming T is the result type. T = Context.getFunctionNoProtoType(T); } } else if (FTI.ArgInfo[0].Param == 0) { // C99 6.7.5.3p3: Reject int(x,y,z) when it's not a function definition. Diag(FTI.ArgInfo[0].IdentLoc, diag::err_ident_list_in_fn_declaration); } else { // Otherwise, we have a function with an argument list that is // potentially variadic. llvm::SmallVector ArgTys; for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { ParmVarDecl *Param = cast(FTI.ArgInfo[i].Param.getAs()); QualType ArgTy = Param->getType(); assert(!ArgTy.isNull() && "Couldn't parse type?"); // Adjust the parameter type. assert((ArgTy == adjustParameterType(ArgTy)) && "Unadjusted type?"); // Look for 'void'. void is allowed only as a single argument to a // function with no other parameters (C99 6.7.5.3p10). We record // int(void) as a FunctionProtoType with an empty argument list. if (ArgTy->isVoidType()) { // If this is something like 'float(int, void)', reject it. 'void' // is an incomplete type (C99 6.2.5p19) and function decls cannot // have arguments of incomplete type. if (FTI.NumArgs != 1 || FTI.isVariadic) { Diag(DeclType.Loc, diag::err_void_only_param); ArgTy = Context.IntTy; Param->setType(ArgTy); } else if (FTI.ArgInfo[i].Ident) { // Reject, but continue to parse 'int(void abc)'. Diag(FTI.ArgInfo[i].IdentLoc, diag::err_param_with_void_type); ArgTy = Context.IntTy; Param->setType(ArgTy); } else { // Reject, but continue to parse 'float(const void)'. if (ArgTy.getCVRQualifiers()) Diag(DeclType.Loc, diag::err_void_param_qualified); // Do not add 'void' to the ArgTys list. break; } } else if (!FTI.hasPrototype) { if (ArgTy->isPromotableIntegerType()) { ArgTy = Context.IntTy; } else if (const BuiltinType* BTy = ArgTy->getAsBuiltinType()) { if (BTy->getKind() == BuiltinType::Float) ArgTy = Context.DoubleTy; } } ArgTys.push_back(ArgTy); } llvm::SmallVector Exceptions; Exceptions.reserve(FTI.NumExceptions); for(unsigned ei = 0, ee = FTI.NumExceptions; ei != ee; ++ei) { QualType ET = QualType::getFromOpaquePtr(FTI.Exceptions[ei].Ty); // Check that the type is valid for an exception spec, and drop it if // not. if (!CheckSpecifiedExceptionType(ET, FTI.Exceptions[ei].Range)) Exceptions.push_back(ET); } T = Context.getFunctionType(T, ArgTys.data(), ArgTys.size(), FTI.isVariadic, FTI.TypeQuals, FTI.hasExceptionSpec, FTI.hasAnyExceptionSpec, Exceptions.size(), Exceptions.data()); } break; } case DeclaratorChunk::MemberPointer: // Verify that we're not building a pointer to pointer to function with // exception specification. if (getLangOptions().CPlusPlus && CheckDistantExceptionSpec(T)) { Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec); D.setInvalidType(true); // Build the type anyway. } // The scope spec must refer to a class, or be dependent. DeclContext *DC = computeDeclContext(DeclType.Mem.Scope()); QualType ClsType; // FIXME: Extend for dependent types when it's actually supported. // See ActOnCXXNestedNameSpecifier. if (CXXRecordDecl *RD = dyn_cast_or_null(DC)) { ClsType = Context.getTagDeclType(RD); } else { if (DC) { Diag(DeclType.Mem.Scope().getBeginLoc(), diag::err_illegal_decl_mempointer_in_nonclass) << (D.getIdentifier() ? D.getIdentifier()->getName() : "type name") << DeclType.Mem.Scope().getRange(); } D.setInvalidType(true); ClsType = Context.IntTy; } // C++ 8.3.3p3: A pointer to member shall not pointer to ... a member // with reference type, or "cv void." if (T->isReferenceType()) { Diag(DeclType.Loc, diag::err_illegal_decl_pointer_to_reference) << (D.getIdentifier() ? D.getIdentifier()->getName() : "type name"); D.setInvalidType(true); T = Context.IntTy; } if (T->isVoidType()) { Diag(DeclType.Loc, diag::err_illegal_decl_mempointer_to_void) << (D.getIdentifier() ? D.getIdentifier()->getName() : "type name"); T = Context.IntTy; } // Enforce C99 6.7.3p2: "Types other than pointer types derived from // object or incomplete types shall not be restrict-qualified." if ((DeclType.Mem.TypeQuals & QualType::Restrict) && !T->isIncompleteOrObjectType()) { Diag(DeclType.Loc, diag::err_typecheck_invalid_restrict_invalid_pointee) << T; DeclType.Mem.TypeQuals &= ~QualType::Restrict; } T = Context.getMemberPointerType(T, ClsType.getTypePtr()). getQualifiedType(DeclType.Mem.TypeQuals); break; } if (T.isNull()) { D.setInvalidType(true); T = Context.IntTy; } // See if there are any attributes on this declarator chunk. if (const AttributeList *AL = DeclType.getAttrs()) ProcessTypeAttributeList(T, AL); } if (getLangOptions().CPlusPlus && T->isFunctionType()) { const FunctionProtoType *FnTy = T->getAsFunctionProtoType(); assert(FnTy && "Why oh why is there not a FunctionProtoType here ?"); // C++ 8.3.5p4: A cv-qualifier-seq shall only be part of the function type // for a nonstatic member function, the function type to which a pointer // to member refers, or the top-level function type of a function typedef // declaration. if (FnTy->getTypeQuals() != 0 && D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef && ((D.getContext() != Declarator::MemberContext && (!D.getCXXScopeSpec().isSet() || !computeDeclContext(D.getCXXScopeSpec())->isRecord())) || D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static)) { if (D.isFunctionDeclarator()) Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_function_type); else Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_typedef_function_type_use); // Strip the cv-quals from the type. T = Context.getFunctionType(FnTy->getResultType(), FnTy->arg_type_begin(), FnTy->getNumArgs(), FnTy->isVariadic(), 0); } } // If there were any type attributes applied to the decl itself (not the // type, apply the type attribute to the type!) if (const AttributeList *Attrs = D.getAttributes()) ProcessTypeAttributeList(T, Attrs); return T; } /// CheckSpecifiedExceptionType - Check if the given type is valid in an /// exception specification. Incomplete types, or pointers to incomplete types /// other than void are not allowed. bool Sema::CheckSpecifiedExceptionType(QualType T, const SourceRange &Range) { // FIXME: This may not correctly work with the fix for core issue 437, // where a class's own type is considered complete within its body. // C++ 15.4p2: A type denoted in an exception-specification shall not denote // an incomplete type. if (T->isIncompleteType()) return Diag(Range.getBegin(), diag::err_incomplete_in_exception_spec) << Range << T << /*direct*/0; // C++ 15.4p2: A type denoted in an exception-specification shall not denote // an incomplete type a pointer or reference to an incomplete type, other // than (cv) void*. int kind; if (const PointerType* IT = T->getAsPointerType()) { T = IT->getPointeeType(); kind = 1; } else if (const ReferenceType* IT = T->getAsReferenceType()) { T = IT->getPointeeType(); kind = 2; } else return false; if (T->isIncompleteType() && !T->isVoidType()) return Diag(Range.getBegin(), diag::err_incomplete_in_exception_spec) << Range << T << /*indirect*/kind; return false; } /// CheckDistantExceptionSpec - Check if the given type is a pointer or pointer /// to member to a function with an exception specification. This means that /// it is invalid to add another level of indirection. bool Sema::CheckDistantExceptionSpec(QualType T) { if (const PointerType *PT = T->getAsPointerType()) T = PT->getPointeeType(); else if (const MemberPointerType *PT = T->getAsMemberPointerType()) T = PT->getPointeeType(); else return false; const FunctionProtoType *FnT = T->getAsFunctionProtoType(); if (!FnT) return false; return FnT->hasExceptionSpec(); } /// ObjCGetTypeForMethodDefinition - Builds the type for a method definition /// declarator QualType Sema::ObjCGetTypeForMethodDefinition(DeclPtrTy D) { ObjCMethodDecl *MDecl = cast(D.getAs()); QualType T = MDecl->getResultType(); llvm::SmallVector ArgTys; // Add the first two invisible argument types for self and _cmd. if (MDecl->isInstanceMethod()) { QualType selfTy = Context.getObjCInterfaceType(MDecl->getClassInterface()); selfTy = Context.getPointerType(selfTy); ArgTys.push_back(selfTy); } else ArgTys.push_back(Context.getObjCIdType()); ArgTys.push_back(Context.getObjCSelType()); for (ObjCMethodDecl::param_iterator PI = MDecl->param_begin(), E = MDecl->param_end(); PI != E; ++PI) { QualType ArgTy = (*PI)->getType(); assert(!ArgTy.isNull() && "Couldn't parse type?"); ArgTy = adjustParameterType(ArgTy); ArgTys.push_back(ArgTy); } T = Context.getFunctionType(T, &ArgTys[0], ArgTys.size(), MDecl->isVariadic(), 0); return T; } /// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types that /// may be similar (C++ 4.4), replaces T1 and T2 with the type that /// they point to and return true. If T1 and T2 aren't pointer types /// or pointer-to-member types, or if they are not similar at this /// level, returns false and leaves T1 and T2 unchanged. Top-level /// qualifiers on T1 and T2 are ignored. This function will typically /// be called in a loop that successively "unwraps" pointer and /// pointer-to-member types to compare them at each level. bool Sema::UnwrapSimilarPointerTypes(QualType& T1, QualType& T2) { const PointerType *T1PtrType = T1->getAsPointerType(), *T2PtrType = T2->getAsPointerType(); if (T1PtrType && T2PtrType) { T1 = T1PtrType->getPointeeType(); T2 = T2PtrType->getPointeeType(); return true; } const MemberPointerType *T1MPType = T1->getAsMemberPointerType(), *T2MPType = T2->getAsMemberPointerType(); if (T1MPType && T2MPType && Context.getCanonicalType(T1MPType->getClass()) == Context.getCanonicalType(T2MPType->getClass())) { T1 = T1MPType->getPointeeType(); T2 = T2MPType->getPointeeType(); return true; } return false; } Sema::TypeResult Sema::ActOnTypeName(Scope *S, Declarator &D) { // C99 6.7.6: Type names have no identifier. This is already validated by // the parser. assert(D.getIdentifier() == 0 && "Type name should have no identifier!"); TagDecl *OwnedTag = 0; QualType T = GetTypeForDeclarator(D, S, /*Skip=*/0, &OwnedTag); if (D.isInvalidType()) return true; if (getLangOptions().CPlusPlus) { // Check that there are no default arguments (C++ only). CheckExtraCXXDefaultArguments(D); // C++0x [dcl.type]p3: // A type-specifier-seq shall not define a class or enumeration // unless it appears in the type-id of an alias-declaration // (7.1.3). if (OwnedTag && OwnedTag->isDefinition()) Diag(OwnedTag->getLocation(), diag::err_type_defined_in_type_specifier) << Context.getTypeDeclType(OwnedTag); } return T.getAsOpaquePtr(); } //===----------------------------------------------------------------------===// // Type Attribute Processing //===----------------------------------------------------------------------===// /// HandleAddressSpaceTypeAttribute - Process an address_space attribute on the /// specified type. The attribute contains 1 argument, the id of the address /// space for the type. static void HandleAddressSpaceTypeAttribute(QualType &Type, const AttributeList &Attr, Sema &S){ // If this type is already address space qualified, reject it. // Clause 6.7.3 - Type qualifiers: "No type shall be qualified by qualifiers // for two or more different address spaces." if (Type.getAddressSpace()) { S.Diag(Attr.getLoc(), diag::err_attribute_address_multiple_qualifiers); return; } // Check the attribute arguments. if (Attr.getNumArgs() != 1) { S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1; return; } Expr *ASArgExpr = static_cast(Attr.getArg(0)); llvm::APSInt addrSpace(32); if (!ASArgExpr->isIntegerConstantExpr(addrSpace, S.Context)) { S.Diag(Attr.getLoc(), diag::err_attribute_address_space_not_int) << ASArgExpr->getSourceRange(); return; } unsigned ASIdx = static_cast(addrSpace.getZExtValue()); Type = S.Context.getAddrSpaceQualType(Type, ASIdx); } /// HandleObjCGCTypeAttribute - Process an objc's gc attribute on the /// specified type. The attribute contains 1 argument, weak or strong. static void HandleObjCGCTypeAttribute(QualType &Type, const AttributeList &Attr, Sema &S) { if (Type.getObjCGCAttr() != QualType::GCNone) { S.Diag(Attr.getLoc(), diag::err_attribute_multiple_objc_gc); return; } // Check the attribute arguments. if (!Attr.getParameterName()) { S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_string) << "objc_gc" << 1; return; } QualType::GCAttrTypes GCAttr; if (Attr.getNumArgs() != 0) { S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1; return; } if (Attr.getParameterName()->isStr("weak")) GCAttr = QualType::Weak; else if (Attr.getParameterName()->isStr("strong")) GCAttr = QualType::Strong; else { S.Diag(Attr.getLoc(), diag::warn_attribute_type_not_supported) << "objc_gc" << Attr.getParameterName(); return; } Type = S.Context.getObjCGCQualType(Type, GCAttr); } void Sema::ProcessTypeAttributeList(QualType &Result, const AttributeList *AL) { // Scan through and apply attributes to this type where it makes sense. Some // attributes (such as __address_space__, __vector_size__, etc) apply to the // type, but others can be present in the type specifiers even though they // apply to the decl. Here we apply type attributes and ignore the rest. for (; AL; AL = AL->getNext()) { // If this is an attribute we can handle, do so now, otherwise, add it to // the LeftOverAttrs list for rechaining. switch (AL->getKind()) { default: break; case AttributeList::AT_address_space: HandleAddressSpaceTypeAttribute(Result, *AL, *this); break; case AttributeList::AT_objc_gc: HandleObjCGCTypeAttribute(Result, *AL, *this); break; } } } /// @brief Ensure that the type T is a complete type. /// /// This routine checks whether the type @p T is complete in any /// context where a complete type is required. If @p T is a complete /// type, returns false. If @p T is a class template specialization, /// this routine then attempts to perform class template /// instantiation. If instantiation fails, or if @p T is incomplete /// and cannot be completed, issues the diagnostic @p diag (giving it /// the type @p T) and returns true. /// /// @param Loc The location in the source that the incomplete type /// diagnostic should refer to. /// /// @param T The type that this routine is examining for completeness. /// /// @param diag The diagnostic value (e.g., /// @c diag::err_typecheck_decl_incomplete_type) that will be used /// for the error message if @p T is incomplete. /// /// @param Range1 An optional range in the source code that will be a /// part of the "incomplete type" error message. /// /// @param Range2 An optional range in the source code that will be a /// part of the "incomplete type" error message. /// /// @param PrintType If non-NULL, the type that should be printed /// instead of @p T. This parameter should be used when the type that /// we're checking for incompleteness isn't the type that should be /// displayed to the user, e.g., when T is a type and PrintType is a /// pointer to T. /// /// @returns @c true if @p T is incomplete and a diagnostic was emitted, /// @c false otherwise. bool Sema::RequireCompleteType(SourceLocation Loc, QualType T, unsigned diag, SourceRange Range1, SourceRange Range2, QualType PrintType) { // FIXME: Add this assertion to help us flush out problems with // checking for dependent types and type-dependent expressions. // // assert(!T->isDependentType() && // "Can't ask whether a dependent type is complete"); // If we have a complete type, we're done. if (!T->isIncompleteType()) return false; // If we have a class template specialization or a class member of a // class template specialization, try to instantiate it. if (const RecordType *Record = T->getAsRecordType()) { if (ClassTemplateSpecializationDecl *ClassTemplateSpec = dyn_cast(Record->getDecl())) { if (ClassTemplateSpec->getSpecializationKind() == TSK_Undeclared) { // Update the class template specialization's location to // refer to the point of instantiation. if (Loc.isValid()) ClassTemplateSpec->setLocation(Loc); return InstantiateClassTemplateSpecialization(ClassTemplateSpec, /*ExplicitInstantiation=*/false); } } else if (CXXRecordDecl *Rec = dyn_cast(Record->getDecl())) { if (CXXRecordDecl *Pattern = Rec->getInstantiatedFromMemberClass()) { // Find the class template specialization that surrounds this // member class. ClassTemplateSpecializationDecl *Spec = 0; for (DeclContext *Parent = Rec->getDeclContext(); Parent && !Spec; Parent = Parent->getParent()) Spec = dyn_cast(Parent); assert(Spec && "Not a member of a class template specialization?"); return InstantiateClass(Loc, Rec, Pattern, Spec->getTemplateArgs(), /*ExplicitInstantiation=*/false); } } } if (PrintType.isNull()) PrintType = T; // We have an incomplete type. Produce a diagnostic. Diag(Loc, diag) << PrintType << Range1 << Range2; // If the type was a forward declaration of a class/struct/union // type, produce const TagType *Tag = 0; if (const RecordType *Record = T->getAsRecordType()) Tag = Record; else if (const EnumType *Enum = T->getAsEnumType()) Tag = Enum; if (Tag && !Tag->getDecl()->isInvalidDecl()) Diag(Tag->getDecl()->getLocation(), Tag->isBeingDefined() ? diag::note_type_being_defined : diag::note_forward_declaration) << QualType(Tag, 0); return true; } /// \brief Retrieve a version of the type 'T' that is qualified by the /// nested-name-specifier contained in SS. QualType Sema::getQualifiedNameType(const CXXScopeSpec &SS, QualType T) { if (!SS.isSet() || SS.isInvalid() || T.isNull()) return T; NestedNameSpecifier *NNS = static_cast(SS.getScopeRep()); return Context.getQualifiedNameType(NNS, T); }