/// \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);
}
/// 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 {
T = ConvertDeclSpecToType(DS);
if (T.isNull())
return T;
}
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 (DeclType.Cls.TypeQuals)
Diag(D.getIdentifierLoc(), diag::err_qualified_block_pointer_type);
if (!T.getTypePtr()->isFunctionType())
Diag(D.getIdentifierLoc(), diag::err_nonfunction_block_type);
else
T = Context.getBlockPointerType(T);
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;
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;
}
/// \brief Convert the specified declspec to the appropriate type
/// object.
/// \param DS the declaration specifiers
/// \returns The type described by the declaration specifiers, or NULL
/// if there was an error.
QualType Sema::ConvertDeclSpecToType(const DeclSpec &DS) {
// 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())
Diag(DS.getSourceRange().getBegin(), diag::warn_missing_declspec)
<< 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++?
unsigned DK = getLangOptions().CPlusPlus && !getLangOptions().Microsoft?
diag::err_missing_type_specifier
: diag::warn_missing_type_specifier;
Diag(DS.getSourceRange().getBegin(), DK);
// 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));
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())
// Class<protocol-list>
Diag(DS.getSourceRange().getBegin(),
diag::err_qualified_class_unsupported) << DS.getSourceRange();
else
Diag(DS.getSourceRange().getBegin(),
diag::err_invalid_protocol_qualifiers) << DS.getSourceRange();
}
// 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:
return QualType();
}
// 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;
}
/// \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);
}
/// CheckStaticCast - Check that a static_cast\<DestType\>(SrcExpr) is valid.
/// Refer to C++ 5.2.9 for details. Static casts are mostly used for making
/// implicit conversions explicit and getting rid of data loss warnings.
void
CheckStaticCast(Sema &Self, Expr *&SrcExpr, QualType DestType,
const SourceRange &OpRange)
{
// The order the tests is not entirely arbitrary. There is one conversion
// that can be handled in two different ways. Given:
// struct A {};
// struct B : public A {
// B(); B(const A&);
// };
// const A &a = B();
// the cast static_cast<const B&>(a) could be seen as either a static
// reference downcast, or an explicit invocation of the user-defined
// conversion using B's conversion constructor.
// DR 427 specifies that the downcast is to be applied here.
// FIXME: With N2812, casts to rvalue refs will change.
// C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
if (DestType->isVoidType()) {
return;
}
// C++ 5.2.9p5, reference downcast.
// See the function for details.
// DR 427 specifies that this is to be applied before paragraph 2.
if (TryStaticReferenceDowncast(Self, SrcExpr, DestType, OpRange)
> TSC_NotApplicable) {
return;
}
// N2844 5.2.9p3: An lvalue of type "cv1 T1" can be cast to type "rvalue
// reference to cv2 T2" if "cv2 T2" is reference-compatible with "cv1 T1".
if (TryLValueToRValueCast(Self, SrcExpr, DestType, OpRange) >
TSC_NotApplicable) {
return;
}
// C++ 5.2.9p2: An expression e can be explicitly converted to a type T
// [...] if the declaration "T t(e);" is well-formed, [...].
if (TryStaticImplicitCast(Self, SrcExpr, DestType, OpRange) >
TSC_NotApplicable) {
return;
}
// C++ 5.2.9p6: May apply the reverse of any standard conversion, except
// lvalue-to-rvalue, array-to-pointer, function-to-pointer, and boolean
// conversions, subject to further restrictions.
// Also, C++ 5.2.9p1 forbids casting away constness, which makes reversal
// of qualification conversions impossible.
// The lvalue-to-rvalue, array-to-pointer and function-to-pointer conversions
// are applied to the expression.
QualType OrigSrcType = SrcExpr->getType();
Self.DefaultFunctionArrayConversion(SrcExpr);
QualType SrcType = Self.Context.getCanonicalType(SrcExpr->getType());
// Reverse integral promotion/conversion. All such conversions are themselves
// again integral promotions or conversions and are thus already handled by
// p2 (TryDirectInitialization above).
// (Note: any data loss warnings should be suppressed.)
// The exception is the reverse of enum->integer, i.e. integer->enum (and
// enum->enum). See also C++ 5.2.9p7.
// The same goes for reverse floating point promotion/conversion and
// floating-integral conversions. Again, only floating->enum is relevant.
if (DestType->isEnumeralType()) {
if (SrcType->isComplexType() || SrcType->isVectorType()) {
// Fall through - these cannot be converted.
} else if (SrcType->isArithmeticType() || SrcType->isEnumeralType()) {
return;
}
}
// Reverse pointer upcast. C++ 4.10p3 specifies pointer upcast.
// C++ 5.2.9p8 additionally disallows a cast path through virtual inheritance.
if (TryStaticPointerDowncast(Self, SrcType, DestType, OpRange)
> TSC_NotApplicable) {
return;
}
// Reverse member pointer conversion. C++ 4.11 specifies member pointer
// conversion. C++ 5.2.9p9 has additional information.
// DR54's access restrictions apply here also.
if (TryStaticMemberPointerUpcast(Self, SrcType, DestType, OpRange)
> TSC_NotApplicable) {
return;
}
// Reverse pointer conversion to void*. C++ 4.10.p2 specifies conversion to
// void*. C++ 5.2.9p10 specifies additional restrictions, which really is
// just the usual constness stuff.
if (const PointerType *SrcPointer = SrcType->getAsPointerType()) {
QualType SrcPointee = SrcPointer->getPointeeType();
if (SrcPointee->isVoidType()) {
if (const PointerType *DestPointer = DestType->getAsPointerType()) {
QualType DestPointee = DestPointer->getPointeeType();
if (DestPointee->isIncompleteOrObjectType()) {
// This is definitely the intended conversion, but it might fail due
// to a const violation.
if (!DestPointee.isAtLeastAsQualifiedAs(SrcPointee)) {
Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_const_away)
<< "static_cast" << DestType << OrigSrcType << OpRange;
}
return;
}
}
}
}
// We tried everything. Everything! Nothing works! :-(
// FIXME: Error reporting could be a lot better. Should store the reason why
// every substep failed and, at the end, select the most specific and report
// that.
Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_generic)
<< "static_cast" << DestType << OrigSrcType
<< OpRange;
}
