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//===--- 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:
// "<proto1,proto2>" 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
assert(0 && "FIXME: GNU decimal extensions not supported yet!");
case DeclSpec::TST_class:
case DeclSpec::TST_enum:
case DeclSpec::TST_union:
case DeclSpec::TST_struct: {
Decl *D = static_cast<Decl *>(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<TypeDecl>(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<protocol-list>
Result = Context.getObjCQualifiedIdType((ObjCProtocolDecl**)PQ,
DS.getNumProtocolQualifiers());
else if (Result == Context.getObjCClassType()) {
if (DeclLoc.isInvalid())
DeclLoc = DS.getSourceRange().getBegin();
// Class<protocol-list>
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<TypedefType>(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<Expr *>(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.
QualType Sema::GetTypeForDeclarator(Declarator &D, Scope *S, unsigned Skip) {
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);
}
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:
T = BuildPointerType(T, DeclType.Ptr.TypeQuals, DeclType.Loc, Name);
break;
case DeclaratorChunk::Reference:
T = BuildReferenceType(T, DeclType.Ref.LValueRef,
DeclType.Ref.HasRestrict ? QualType::Restrict : 0,
DeclType.Loc, Name);
break;
case DeclaratorChunk::Array: {
DeclaratorChunk::ArrayTypeInfo &ATI = DeclType.Arr;
Expr *ArraySize = static_cast<Expr*>(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 (FTI.NumArgs == 0) {
if (getLangOptions().CPlusPlus) {
// C++ 8.3.5p2: If the parameter-declaration-clause is empty, the
// function takes no arguments.
T = Context.getFunctionType(T, NULL, 0, FTI.isVariadic,FTI.TypeQuals);
} 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<QualType, 16> ArgTys;
for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) {
ParmVarDecl *Param =
cast<ParmVarDecl>(FTI.ArgInfo[i].Param.getAs<Decl>());
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);
}
T = Context.getFunctionType(T, &ArgTys[0], ArgTys.size(),
FTI.isVariadic, FTI.TypeQuals);
}
break;
}
case DeclaratorChunk::MemberPointer:
// 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<CXXRecordDecl>(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;
}
/// ObjCGetTypeForMethodDefinition - Builds the type for a method definition
/// declarator
QualType Sema::ObjCGetTypeForMethodDefinition(DeclPtrTy D) {
ObjCMethodDecl *MDecl = cast<ObjCMethodDecl>(D.getAs<Decl>());
QualType T = MDecl->getResultType();
llvm::SmallVector<QualType, 16> 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!");
QualType T = GetTypeForDeclarator(D, S);
if (D.isInvalidType())
return true;
// Check that there are no default arguments (C++ only).
if (getLangOptions().CPlusPlus)
CheckExtraCXXDefaultArguments(D);
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<Expr *>(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<unsigned>(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) {
// 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<ClassTemplateSpecializationDecl>(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<CXXRecordDecl>(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<ClassTemplateSpecializationDecl>(Parent);
assert(Spec && "Not a member of a class template specialization?");
return InstantiateClass(Loc, Rec, Pattern, Spec->getTemplateArgs());
}
}
}
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<NestedNameSpecifier *>(SS.getScopeRep());
return Context.getQualifiedNameType(NNS, T);
}