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gerrit-public.fairphone.software / platform / external / clang / ce056bcaa1c97b89a4b2de2112c62d060863be2b / . / lib / Sema / SemaExprCXX.cpp
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//===--- SemaExprCXX.cpp - Semantic Analysis for Expressions --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements semantic analysis for C++ expressions.
//
//===----------------------------------------------------------------------===//
#include "Sema.h"
#include "SemaInit.h"
#include "Lookup.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/CXXInheritance.h"
#include "clang/AST/ExprCXX.h"
#include "clang/Basic/PartialDiagnostic.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Parse/DeclSpec.h"
#include "llvm/ADT/STLExtras.h"
using namespace clang;
Action::TypeTy *Sema::getDestructorName(SourceLocation TildeLoc,
IdentifierInfo &II,
SourceLocation NameLoc,
Scope *S, const CXXScopeSpec &SS,
TypeTy *ObjectTypePtr,
bool EnteringContext) {
// Determine where to perform name lookup.
// FIXME: This area of the standard is very messy, and the current
// wording is rather unclear about which scopes we search for the
// destructor name; see core issues 399 and 555. Issue 399 in
// particular shows where the current description of destructor name
// lookup is completely out of line with existing practice, e.g.,
// this appears to be ill-formed:
//
// namespace N {
// template <typename T> struct S {
// ~S();
// };
// }
//
// void f(N::S<int>* s) {
// s->N::S<int>::~S();
// }
//
//
QualType SearchType;
DeclContext *LookupCtx = 0;
bool isDependent = false;
bool LookInScope = false;
// If we have an object type, it's because we are in a
// pseudo-destructor-expression or a member access expression, and
// we know what type we're looking for.
if (ObjectTypePtr)
SearchType = GetTypeFromParser(ObjectTypePtr);
if (SS.isSet()) {
// C++ [basic.lookup.qual]p6:
// If a pseudo-destructor-name (5.2.4) contains a
// nested-name-specifier, the type-names are looked up as types
// in the scope designated by the nested-name-specifier. Similarly, in
// a qualified-id of the form:
//
// :: [opt] nested-name-specifier[opt] class-name :: ~class-name
//
// the second class-name is looked up in the same scope as the first.
//
// FIXME: We don't implement this, because it breaks lots of
// perfectly reasonable code that no other compilers diagnose. The
// issue is that the first class-name is looked up as a
// nested-name-specifier, so we ignore value declarations, but the
// second lookup is presumably an ordinary name lookup. Hence, we
// end up finding values (say, a function) and complain. See PRs
// 6358 and 6359 for examples of such code. DPG to investigate
// further.
if (ObjectTypePtr) {
LookupCtx = computeDeclContext(SearchType);
isDependent = SearchType->isDependentType();
} else {
LookupCtx = computeDeclContext(SS, EnteringContext);
if (LookupCtx)
isDependent = LookupCtx->isDependentContext();
}
LookInScope = (LookupCtx == 0) && !isDependent;
} else if (ObjectTypePtr) {
// C++ [basic.lookup.classref]p3:
// If the unqualified-id is ~type-name, the type-name is looked up
// in the context of the entire postfix-expression. If the type T
// of the object expression is of a class type C, the type-name is
// also looked up in the scope of class C. At least one of the
// lookups shall find a name that refers to (possibly
// cv-qualified) T.
LookupCtx = computeDeclContext(SearchType);
isDependent = SearchType->isDependentType();
assert((isDependent || !SearchType->isIncompleteType()) &&
"Caller should have completed object type");
LookInScope = true;
} else {
// Perform lookup into the current scope (only).
LookInScope = true;
}
LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName);
for (unsigned Step = 0; Step != 2; ++Step) {
// Look for the name first in the computed lookup context (if we
// have one) and, if that fails to find a match, in the sope (if
// we're allowed to look there).
Found.clear();
if (Step == 0 && LookupCtx)
LookupQualifiedName(Found, LookupCtx);
else if (Step == 1 && LookInScope)
LookupName(Found, S);
else
continue;
// FIXME: Should we be suppressing ambiguities here?
if (Found.isAmbiguous())
return 0;
if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) {
QualType T = Context.getTypeDeclType(Type);
// If we found the injected-class-name of a class template, retrieve the
// type of that template.
// FIXME: We really shouldn't need to do this.
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Type))
if (Record->isInjectedClassName())
if (Record->getDescribedClassTemplate())
T = Record->getDescribedClassTemplate()
->getInjectedClassNameType(Context);
if (SearchType.isNull() || SearchType->isDependentType() ||
Context.hasSameUnqualifiedType(T, SearchType)) {
// We found our type!
return T.getAsOpaquePtr();
}
}
// If the name that we found is a class template name, and it is
// the same name as the template name in the last part of the
// nested-name-specifier (if present) or the object type, then
// this is the destructor for that class.
// FIXME: This is a workaround until we get real drafting for core
// issue 399, for which there isn't even an obvious direction.
if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) {
QualType MemberOfType;
if (SS.isSet()) {
if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) {
// Figure out the type of the context, if it has one.
if (ClassTemplateSpecializationDecl *Spec
= dyn_cast<ClassTemplateSpecializationDecl>(Ctx))
MemberOfType = Context.getTypeDeclType(Spec);
else if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) {
if (Record->getDescribedClassTemplate())
MemberOfType = Record->getDescribedClassTemplate()
->getInjectedClassNameType(Context);
else
MemberOfType = Context.getTypeDeclType(Record);
}
}
}
if (MemberOfType.isNull())
MemberOfType = SearchType;
if (MemberOfType.isNull())
continue;
// We're referring into a class template specialization. If the
// class template we found is the same as the template being
// specialized, we found what we are looking for.
if (const RecordType *Record = MemberOfType->getAs<RecordType>()) {
if (ClassTemplateSpecializationDecl *Spec
= dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) {
if (Spec->getSpecializedTemplate()->getCanonicalDecl() ==
Template->getCanonicalDecl())
return MemberOfType.getAsOpaquePtr();
}
continue;
}
// We're referring to an unresolved class template
// specialization. Determine whether we class template we found
// is the same as the template being specialized or, if we don't
// know which template is being specialized, that it at least
// has the same name.
if (const TemplateSpecializationType *SpecType
= MemberOfType->getAs<TemplateSpecializationType>()) {
TemplateName SpecName = SpecType->getTemplateName();
// The class template we found is the same template being
// specialized.
if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) {
if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl())
return MemberOfType.getAsOpaquePtr();
continue;
}
// The class template we found has the same name as the
// (dependent) template name being specialized.
if (DependentTemplateName *DepTemplate
= SpecName.getAsDependentTemplateName()) {
if (DepTemplate->isIdentifier() &&
DepTemplate->getIdentifier() == Template->getIdentifier())
return MemberOfType.getAsOpaquePtr();
continue;
}
}
}
}
if (isDependent) {
// We didn't find our type, but that's okay: it's dependent
// anyway.
NestedNameSpecifier *NNS = 0;
SourceRange Range;
if (SS.isSet()) {
NNS = (NestedNameSpecifier *)SS.getScopeRep();
Range = SourceRange(SS.getRange().getBegin(), NameLoc);
} else {
NNS = NestedNameSpecifier::Create(Context, &II);
Range = SourceRange(NameLoc);
}
return CheckTypenameType(NNS, II, Range).getAsOpaquePtr();
}
if (ObjectTypePtr)
Diag(NameLoc, diag::err_ident_in_pseudo_dtor_not_a_type)
<< &II;
else
Diag(NameLoc, diag::err_destructor_class_name);
return 0;
}
/// ActOnCXXTypeidOfType - Parse typeid( type-id ).
Action::OwningExprResult
Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc,
bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
if (!StdNamespace)
return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
if (isType) {
// C++ [expr.typeid]p4:
// The top-level cv-qualifiers of the lvalue expression or the type-id
// that is the operand of typeid are always ignored.
// FIXME: Preserve type source info.
// FIXME: Preserve the type before we stripped the cv-qualifiers?
QualType T = GetTypeFromParser(TyOrExpr);
if (T.isNull())
return ExprError();
// C++ [expr.typeid]p4:
// If the type of the type-id is a class type or a reference to a class
// type, the class shall be completely-defined.
QualType CheckT = T;
if (const ReferenceType *RefType = CheckT->getAs<ReferenceType>())
CheckT = RefType->getPointeeType();
if (CheckT->getAs<RecordType>() &&
RequireCompleteType(OpLoc, CheckT, diag::err_incomplete_typeid))
return ExprError();
TyOrExpr = T.getUnqualifiedType().getAsOpaquePtr();
}
IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName);
LookupQualifiedName(R, StdNamespace);
RecordDecl *TypeInfoRecordDecl = R.getAsSingle<RecordDecl>();
if (!TypeInfoRecordDecl)
return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
QualType TypeInfoType = Context.getTypeDeclType(TypeInfoRecordDecl);
if (!isType) {
bool isUnevaluatedOperand = true;
Expr *E = static_cast<Expr *>(TyOrExpr);
if (E && !E->isTypeDependent()) {
QualType T = E->getType();
if (const RecordType *RecordT = T->getAs<RecordType>()) {
CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl());
// C++ [expr.typeid]p3:
// [...] If the type of the expression is a class type, the class
// shall be completely-defined.
if (RequireCompleteType(OpLoc, T, diag::err_incomplete_typeid))
return ExprError();
// C++ [expr.typeid]p3:
// When typeid is applied to an expression other than an lvalue of a
// polymorphic class type [...] [the] expression is an unevaluated
// operand. [...]
if (RecordD->isPolymorphic() && E->isLvalue(Context) == Expr::LV_Valid)
isUnevaluatedOperand = false;
}
// C++ [expr.typeid]p4:
// [...] If the type of the type-id is a reference to a possibly
// cv-qualified type, the result of the typeid expression refers to a
// std::type_info object representing the cv-unqualified referenced
// type.
if (T.hasQualifiers()) {
ImpCastExprToType(E, T.getUnqualifiedType(), CastExpr::CK_NoOp,
E->isLvalue(Context));
TyOrExpr = E;
}
}
// If this is an unevaluated operand, clear out the set of
// declaration references we have been computing and eliminate any
// temporaries introduced in its computation.
if (isUnevaluatedOperand)
ExprEvalContexts.back().Context = Unevaluated;
}
return Owned(new (Context) CXXTypeidExpr(isType, TyOrExpr,
TypeInfoType.withConst(),
SourceRange(OpLoc, RParenLoc)));
}
/// ActOnCXXBoolLiteral - Parse {true,false} literals.
Action::OwningExprResult
Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
"Unknown C++ Boolean value!");
return Owned(new (Context) CXXBoolLiteralExpr(Kind == tok::kw_true,
Context.BoolTy, OpLoc));
}
/// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
Action::OwningExprResult
Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) {
return Owned(new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc));
}
/// ActOnCXXThrow - Parse throw expressions.
Action::OwningExprResult
Sema::ActOnCXXThrow(SourceLocation OpLoc, ExprArg E) {
Expr *Ex = E.takeAs<Expr>();
if (Ex && !Ex->isTypeDependent() && CheckCXXThrowOperand(OpLoc, Ex))
return ExprError();
return Owned(new (Context) CXXThrowExpr(Ex, Context.VoidTy, OpLoc));
}
/// CheckCXXThrowOperand - Validate the operand of a throw.
bool Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc, Expr *&E) {
// C++ [except.throw]p3:
// A throw-expression initializes a temporary object, called the exception
// object, the type of which is determined by removing any top-level
// cv-qualifiers from the static type of the operand of throw and adjusting
// the type from "array of T" or "function returning T" to "pointer to T"
// or "pointer to function returning T", [...]
if (E->getType().hasQualifiers())
ImpCastExprToType(E, E->getType().getUnqualifiedType(), CastExpr::CK_NoOp,
E->isLvalue(Context) == Expr::LV_Valid);
DefaultFunctionArrayConversion(E);
// If the type of the exception would be an incomplete type or a pointer
// to an incomplete type other than (cv) void the program is ill-formed.
QualType Ty = E->getType();
int isPointer = 0;
if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
Ty = Ptr->getPointeeType();
isPointer = 1;
}
if (!isPointer || !Ty->isVoidType()) {
if (RequireCompleteType(ThrowLoc, Ty,
PDiag(isPointer ? diag::err_throw_incomplete_ptr
: diag::err_throw_incomplete)
<< E->getSourceRange()))
return true;
}
// FIXME: Construct a temporary here.
return false;
}
Action::OwningExprResult Sema::ActOnCXXThis(SourceLocation ThisLoc) {
/// C++ 9.3.2: In the body of a non-static member function, the keyword this
/// is a non-lvalue expression whose value is the address of the object for
/// which the function is called.
if (!isa<FunctionDecl>(CurContext))
return ExprError(Diag(ThisLoc, diag::err_invalid_this_use));
if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext))
if (MD->isInstance())
return Owned(new (Context) CXXThisExpr(ThisLoc,
MD->getThisType(Context),
/*isImplicit=*/false));
return ExprError(Diag(ThisLoc, diag::err_invalid_this_use));
}
/// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
/// Can be interpreted either as function-style casting ("int(x)")
/// or class type construction ("ClassType(x,y,z)")
/// or creation of a value-initialized type ("int()").
Action::OwningExprResult
Sema::ActOnCXXTypeConstructExpr(SourceRange TypeRange, TypeTy *TypeRep,
SourceLocation LParenLoc,
MultiExprArg exprs,
SourceLocation *CommaLocs,
SourceLocation RParenLoc) {
if (!TypeRep)
return ExprError();
TypeSourceInfo *TInfo;
QualType Ty = GetTypeFromParser(TypeRep, &TInfo);
if (!TInfo)
TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation());
unsigned NumExprs = exprs.size();
Expr **Exprs = (Expr**)exprs.get();
SourceLocation TyBeginLoc = TypeRange.getBegin();
SourceRange FullRange = SourceRange(TyBeginLoc, RParenLoc);
if (Ty->isDependentType() ||
CallExpr::hasAnyTypeDependentArguments(Exprs, NumExprs)) {
exprs.release();
return Owned(CXXUnresolvedConstructExpr::Create(Context,
TypeRange.getBegin(), Ty,
LParenLoc,
Exprs, NumExprs,
RParenLoc));
}
if (Ty->isArrayType())
return ExprError(Diag(TyBeginLoc,
diag::err_value_init_for_array_type) << FullRange);
if (!Ty->isVoidType() &&
RequireCompleteType(TyBeginLoc, Ty,
PDiag(diag::err_invalid_incomplete_type_use)
<< FullRange))
return ExprError();
if (RequireNonAbstractType(TyBeginLoc, Ty,
diag::err_allocation_of_abstract_type))
return ExprError();
// C++ [expr.type.conv]p1:
// If the expression list is a single expression, the type conversion
// expression is equivalent (in definedness, and if defined in meaning) to the
// corresponding cast expression.
//
if (NumExprs == 1) {
CastExpr::CastKind Kind = CastExpr::CK_Unknown;
CXXMethodDecl *Method = 0;
if (CheckCastTypes(TypeRange, Ty, Exprs[0], Kind, Method,
/*FunctionalStyle=*/true))
return ExprError();
exprs.release();
if (Method) {
OwningExprResult CastArg
= BuildCXXCastArgument(TypeRange.getBegin(), Ty.getNonReferenceType(),
Kind, Method, Owned(Exprs[0]));
if (CastArg.isInvalid())
return ExprError();
Exprs[0] = CastArg.takeAs<Expr>();
}
return Owned(new (Context) CXXFunctionalCastExpr(Ty.getNonReferenceType(),
TInfo, TyBeginLoc, Kind,
Exprs[0], RParenLoc));
}
if (const RecordType *RT = Ty->getAs<RecordType>()) {
CXXRecordDecl *Record = cast<CXXRecordDecl>(RT->getDecl());
if (NumExprs > 1 || !Record->hasTrivialConstructor() ||
!Record->hasTrivialDestructor()) {
InitializedEntity Entity = InitializedEntity::InitializeTemporary(Ty);
InitializationKind Kind
= NumExprs ? InitializationKind::CreateDirect(TypeRange.getBegin(),
LParenLoc, RParenLoc)
: InitializationKind::CreateValue(TypeRange.getBegin(),
LParenLoc, RParenLoc);
InitializationSequence InitSeq(*this, Entity, Kind, Exprs, NumExprs);
OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind,
move(exprs));
// FIXME: Improve AST representation?
return move(Result);
}
// Fall through to value-initialize an object of class type that
// doesn't have a user-declared default constructor.
}
// C++ [expr.type.conv]p1:
// If the expression list specifies more than a single value, the type shall
// be a class with a suitably declared constructor.
//
if (NumExprs > 1)
return ExprError(Diag(CommaLocs[0],
diag::err_builtin_func_cast_more_than_one_arg)
<< FullRange);
assert(NumExprs == 0 && "Expected 0 expressions");
// C++ [expr.type.conv]p2:
// The expression T(), where T is a simple-type-specifier for a non-array
// complete object type or the (possibly cv-qualified) void type, creates an
// rvalue of the specified type, which is value-initialized.
//
exprs.release();
return Owned(new (Context) CXXZeroInitValueExpr(Ty, TyBeginLoc, RParenLoc));
}
/// ActOnCXXNew - Parsed a C++ 'new' expression (C++ 5.3.4), as in e.g.:
/// @code new (memory) int[size][4] @endcode
/// or
/// @code ::new Foo(23, "hello") @endcode
/// For the interpretation of this heap of arguments, consult the base version.
Action::OwningExprResult
Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
SourceLocation PlacementRParen, bool ParenTypeId,
Declarator &D, SourceLocation ConstructorLParen,
MultiExprArg ConstructorArgs,
SourceLocation ConstructorRParen) {
Expr *ArraySize = 0;
// If the specified type is an array, unwrap it and save the expression.
if (D.getNumTypeObjects() > 0 &&
D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
DeclaratorChunk &Chunk = D.getTypeObject(0);
if (Chunk.Arr.hasStatic)
return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
<< D.getSourceRange());
if (!Chunk.Arr.NumElts)
return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
<< D.getSourceRange());
if (ParenTypeId) {
// Can't have dynamic array size when the type-id is in parentheses.
Expr *NumElts = (Expr *)Chunk.Arr.NumElts;
if (!NumElts->isTypeDependent() && !NumElts->isValueDependent() &&
!NumElts->isIntegerConstantExpr(Context)) {
Diag(D.getTypeObject(0).Loc, diag::err_new_paren_array_nonconst)
<< NumElts->getSourceRange();
return ExprError();
}
}
ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
D.DropFirstTypeObject();
}
// Every dimension shall be of constant size.
if (ArraySize) {
for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
if (D.getTypeObject(I).Kind != DeclaratorChunk::Array)
break;
DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr;
if (Expr *NumElts = (Expr *)Array.NumElts) {
if (!NumElts->isTypeDependent() && !NumElts->isValueDependent() &&
!NumElts->isIntegerConstantExpr(Context)) {
Diag(D.getTypeObject(I).Loc, diag::err_new_array_nonconst)
<< NumElts->getSourceRange();
return ExprError();
}
}
}
}
//FIXME: Store TypeSourceInfo in CXXNew expression.
TypeSourceInfo *TInfo = 0;
QualType AllocType = GetTypeForDeclarator(D, /*Scope=*/0, &TInfo);
if (D.isInvalidType())
return ExprError();
return BuildCXXNew(StartLoc, UseGlobal,
PlacementLParen,
move(PlacementArgs),
PlacementRParen,
ParenTypeId,
AllocType,
D.getSourceRange().getBegin(),
D.getSourceRange(),
Owned(ArraySize),
ConstructorLParen,
move(ConstructorArgs),
ConstructorRParen);
}
Sema::OwningExprResult
Sema::BuildCXXNew(SourceLocation StartLoc, bool UseGlobal,
SourceLocation PlacementLParen,
MultiExprArg PlacementArgs,
SourceLocation PlacementRParen,
bool ParenTypeId,
QualType AllocType,
SourceLocation TypeLoc,
SourceRange TypeRange,
ExprArg ArraySizeE,
SourceLocation ConstructorLParen,
MultiExprArg ConstructorArgs,
SourceLocation ConstructorRParen) {
if (CheckAllocatedType(AllocType, TypeLoc, TypeRange))
return ExprError();
QualType ResultType = Context.getPointerType(AllocType);
// That every array dimension except the first is constant was already
// checked by the type check above.
// C++ 5.3.4p6: "The expression in a direct-new-declarator shall have integral
// or enumeration type with a non-negative value."
Expr *ArraySize = (Expr *)ArraySizeE.get();
if (ArraySize && !ArraySize->isTypeDependent()) {
QualType SizeType = ArraySize->getType();
if (!SizeType->isIntegralType() && !SizeType->isEnumeralType())
return ExprError(Diag(ArraySize->getSourceRange().getBegin(),
diag::err_array_size_not_integral)
<< SizeType << ArraySize->getSourceRange());
// Let's see if this is a constant < 0. If so, we reject it out of hand.
// We don't care about special rules, so we tell the machinery it's not
// evaluated - it gives us a result in more cases.
if (!ArraySize->isValueDependent()) {
llvm::APSInt Value;
if (ArraySize->isIntegerConstantExpr(Value, Context, 0, false)) {
if (Value < llvm::APSInt(
llvm::APInt::getNullValue(Value.getBitWidth()),
Value.isUnsigned()))
return ExprError(Diag(ArraySize->getSourceRange().getBegin(),
diag::err_typecheck_negative_array_size)
<< ArraySize->getSourceRange());
}
}
ImpCastExprToType(ArraySize, Context.getSizeType(),
CastExpr::CK_IntegralCast);
}
FunctionDecl *OperatorNew = 0;
FunctionDecl *OperatorDelete = 0;
Expr **PlaceArgs = (Expr**)PlacementArgs.get();
unsigned NumPlaceArgs = PlacementArgs.size();
if (!AllocType->isDependentType() &&
!Expr::hasAnyTypeDependentArguments(PlaceArgs, NumPlaceArgs) &&
FindAllocationFunctions(StartLoc,
SourceRange(PlacementLParen, PlacementRParen),
UseGlobal, AllocType, ArraySize, PlaceArgs,
NumPlaceArgs, OperatorNew, OperatorDelete))
return ExprError();
llvm::SmallVector<Expr *, 8> AllPlaceArgs;
if (OperatorNew) {
// Add default arguments, if any.
const FunctionProtoType *Proto =
OperatorNew->getType()->getAs<FunctionProtoType>();
VariadicCallType CallType =
Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply;
bool Invalid = GatherArgumentsForCall(PlacementLParen, OperatorNew,
Proto, 1, PlaceArgs, NumPlaceArgs,
AllPlaceArgs, CallType);
if (Invalid)
return ExprError();
NumPlaceArgs = AllPlaceArgs.size();
if (NumPlaceArgs > 0)
PlaceArgs = &AllPlaceArgs[0];
}
bool Init = ConstructorLParen.isValid();
// --- Choosing a constructor ---
CXXConstructorDecl *Constructor = 0;
Expr **ConsArgs = (Expr**)ConstructorArgs.get();
unsigned NumConsArgs = ConstructorArgs.size();
ASTOwningVector<&ActionBase::DeleteExpr> ConvertedConstructorArgs(*this);
if (!AllocType->isDependentType() &&
!Expr::hasAnyTypeDependentArguments(ConsArgs, NumConsArgs)) {
// C++0x [expr.new]p15:
// A new-expression that creates an object of type T initializes that
// object as follows:
InitializationKind Kind
// - If the new-initializer is omitted, the object is default-
// initialized (8.5); if no initialization is performed,
// the object has indeterminate value
= !Init? InitializationKind::CreateDefault(TypeLoc)
// - Otherwise, the new-initializer is interpreted according to the
// initialization rules of 8.5 for direct-initialization.
: InitializationKind::CreateDirect(TypeLoc,
ConstructorLParen,
ConstructorRParen);
InitializedEntity Entity
= InitializedEntity::InitializeNew(StartLoc, AllocType);
InitializationSequence InitSeq(*this, Entity, Kind, ConsArgs, NumConsArgs);
OwningExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
move(ConstructorArgs));
if (FullInit.isInvalid())
return ExprError();
// FullInit is our initializer; walk through it to determine if it's a
// constructor call, which CXXNewExpr handles directly.
if (Expr *FullInitExpr = (Expr *)FullInit.get()) {
if (CXXBindTemporaryExpr *Binder
= dyn_cast<CXXBindTemporaryExpr>(FullInitExpr))
FullInitExpr = Binder->getSubExpr();
if (CXXConstructExpr *Construct
= dyn_cast<CXXConstructExpr>(FullInitExpr)) {
Constructor = Construct->getConstructor();
for (CXXConstructExpr::arg_iterator A = Construct->arg_begin(),
AEnd = Construct->arg_end();
A != AEnd; ++A)
ConvertedConstructorArgs.push_back(A->Retain());
} else {
// Take the converted initializer.
ConvertedConstructorArgs.push_back(FullInit.release());
}
} else {
// No initialization required.
}
// Take the converted arguments and use them for the new expression.
NumConsArgs = ConvertedConstructorArgs.size();
ConsArgs = (Expr **)ConvertedConstructorArgs.take();
}
// FIXME: Also check that the destructor is accessible. (C++ 5.3.4p16)
PlacementArgs.release();
ConstructorArgs.release();
ArraySizeE.release();
return Owned(new (Context) CXXNewExpr(Context, UseGlobal, OperatorNew,
PlaceArgs, NumPlaceArgs, ParenTypeId,
ArraySize, Constructor, Init,
ConsArgs, NumConsArgs, OperatorDelete,
ResultType, StartLoc,
Init ? ConstructorRParen :
SourceLocation()));
}
/// CheckAllocatedType - Checks that a type is suitable as the allocated type
/// in a new-expression.
/// dimension off and stores the size expression in ArraySize.
bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc,
SourceRange R) {
// C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
// abstract class type or array thereof.
if (AllocType->isFunctionType())
return Diag(Loc, diag::err_bad_new_type)
<< AllocType << 0 << R;
else if (AllocType->isReferenceType())
return Diag(Loc, diag::err_bad_new_type)
<< AllocType << 1 << R;
else if (!AllocType->isDependentType() &&
RequireCompleteType(Loc, AllocType,
PDiag(diag::err_new_incomplete_type)
<< R))
return true;
else if (RequireNonAbstractType(Loc, AllocType,
diag::err_allocation_of_abstract_type))
return true;
return false;
}
/// FindAllocationFunctions - Finds the overloads of operator new and delete
/// that are appropriate for the allocation.
bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
bool UseGlobal, QualType AllocType,
bool IsArray, Expr **PlaceArgs,
unsigned NumPlaceArgs,
FunctionDecl *&OperatorNew,
FunctionDecl *&OperatorDelete) {
// --- Choosing an allocation function ---
// C++ 5.3.4p8 - 14 & 18
// 1) If UseGlobal is true, only look in the global scope. Else, also look
// in the scope of the allocated class.
// 2) If an array size is given, look for operator new[], else look for
// operator new.
// 3) The first argument is always size_t. Append the arguments from the
// placement form.
// FIXME: Also find the appropriate delete operator.
llvm::SmallVector<Expr*, 8> AllocArgs(1 + NumPlaceArgs);
// We don't care about the actual value of this argument.
// FIXME: Should the Sema create the expression and embed it in the syntax
// tree? Or should the consumer just recalculate the value?
IntegerLiteral Size(llvm::APInt::getNullValue(
Context.Target.getPointerWidth(0)),
Context.getSizeType(),
SourceLocation());
AllocArgs[0] = &Size;
std::copy(PlaceArgs, PlaceArgs + NumPlaceArgs, AllocArgs.begin() + 1);
DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
IsArray ? OO_Array_New : OO_New);
if (AllocType->isRecordType() && !UseGlobal) {
CXXRecordDecl *Record
= cast<CXXRecordDecl>(AllocType->getAs<RecordType>()->getDecl());
// FIXME: We fail to find inherited overloads.
if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0],
AllocArgs.size(), Record, /*AllowMissing=*/true,
OperatorNew))
return true;
}
if (!OperatorNew) {
// Didn't find a member overload. Look for a global one.
DeclareGlobalNewDelete();
DeclContext *TUDecl = Context.getTranslationUnitDecl();
if (FindAllocationOverload(StartLoc, Range, NewName, &AllocArgs[0],
AllocArgs.size(), TUDecl, /*AllowMissing=*/false,
OperatorNew))
return true;
}
// FindAllocationOverload can change the passed in arguments, so we need to
// copy them back.
if (NumPlaceArgs > 0)
std::copy(&AllocArgs[1], AllocArgs.end(), PlaceArgs);
return false;
}
/// FindAllocationOverload - Find an fitting overload for the allocation
/// function in the specified scope.
bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range,
DeclarationName Name, Expr** Args,
unsigned NumArgs, DeclContext *Ctx,
bool AllowMissing, FunctionDecl *&Operator) {
LookupResult R(*this, Name, StartLoc, LookupOrdinaryName);
LookupQualifiedName(R, Ctx);
if (R.empty()) {
if (AllowMissing)
return false;
return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call)
<< Name << Range;
}
// FIXME: handle ambiguity
OverloadCandidateSet Candidates(StartLoc);
for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
Alloc != AllocEnd; ++Alloc) {
// Even member operator new/delete are implicitly treated as
// static, so don't use AddMemberCandidate.
if (FunctionTemplateDecl *FnTemplate =
dyn_cast<FunctionTemplateDecl>((*Alloc)->getUnderlyingDecl())) {
AddTemplateOverloadCandidate(FnTemplate, Alloc.getAccess(),
/*ExplicitTemplateArgs=*/0, Args, NumArgs,
Candidates,
/*SuppressUserConversions=*/false);
continue;
}
FunctionDecl *Fn = cast<FunctionDecl>((*Alloc)->getUnderlyingDecl());
AddOverloadCandidate(Fn, Alloc.getAccess(), Args, NumArgs, Candidates,
/*SuppressUserConversions=*/false);
}
// Do the resolution.
OverloadCandidateSet::iterator Best;
switch(BestViableFunction(Candidates, StartLoc, Best)) {
case OR_Success: {
// Got one!
FunctionDecl *FnDecl = Best->Function;
// The first argument is size_t, and the first parameter must be size_t,
// too. This is checked on declaration and can be assumed. (It can't be
// asserted on, though, since invalid decls are left in there.)
// Whatch out for variadic allocator function.
unsigned NumArgsInFnDecl = FnDecl->getNumParams();
for (unsigned i = 0; (i < NumArgs && i < NumArgsInFnDecl); ++i) {
if (PerformCopyInitialization(Args[i],
FnDecl->getParamDecl(i)->getType(),
AA_Passing))
return true;
}
Operator = FnDecl;
return false;
}
case OR_No_Viable_Function:
Diag(StartLoc, diag::err_ovl_no_viable_function_in_call)
<< Name << Range;
PrintOverloadCandidates(Candidates, OCD_AllCandidates, Args, NumArgs);
return true;
case OR_Ambiguous:
Diag(StartLoc, diag::err_ovl_ambiguous_call)
<< Name << Range;
PrintOverloadCandidates(Candidates, OCD_ViableCandidates, Args, NumArgs);
return true;
case OR_Deleted:
Diag(StartLoc, diag::err_ovl_deleted_call)
<< Best->Function->isDeleted()
<< Name << Range;
PrintOverloadCandidates(Candidates, OCD_AllCandidates, Args, NumArgs);
return true;
}
assert(false && "Unreachable, bad result from BestViableFunction");
return true;
}
/// DeclareGlobalNewDelete - Declare the global forms of operator new and
/// delete. These are:
/// @code
/// void* operator new(std::size_t) throw(std::bad_alloc);
/// void* operator new[](std::size_t) throw(std::bad_alloc);
/// void operator delete(void *) throw();
/// void operator delete[](void *) throw();
/// @endcode
/// Note that the placement and nothrow forms of new are *not* implicitly
/// declared. Their use requires including \<new\>.
void Sema::DeclareGlobalNewDelete() {
if (GlobalNewDeleteDeclared)
return;
// C++ [basic.std.dynamic]p2:
// [...] The following allocation and deallocation functions (18.4) are
// implicitly declared in global scope in each translation unit of a
// program
//
// void* operator new(std::size_t) throw(std::bad_alloc);
// void* operator new[](std::size_t) throw(std::bad_alloc);
// void operator delete(void*) throw();
// void operator delete[](void*) throw();
//
// These implicit declarations introduce only the function names operator
// new, operator new[], operator delete, operator delete[].
//
// Here, we need to refer to std::bad_alloc, so we will implicitly declare
// "std" or "bad_alloc" as necessary to form the exception specification.
// However, we do not make these implicit declarations visible to name
// lookup.
if (!StdNamespace) {
// The "std" namespace has not yet been defined, so build one implicitly.
StdNamespace = NamespaceDecl::Create(Context,
Context.getTranslationUnitDecl(),
SourceLocation(),
&PP.getIdentifierTable().get("std"));
StdNamespace->setImplicit(true);
}
if (!StdBadAlloc) {
// The "std::bad_alloc" class has not yet been declared, so build it
// implicitly.
StdBadAlloc = CXXRecordDecl::Create(Context, TagDecl::TK_class,
StdNamespace,
SourceLocation(),
&PP.getIdentifierTable().get("bad_alloc"),
SourceLocation(), 0);
StdBadAlloc->setImplicit(true);
}
GlobalNewDeleteDeclared = true;
QualType VoidPtr = Context.getPointerType(Context.VoidTy);
QualType SizeT = Context.getSizeType();
bool AssumeSaneOperatorNew = getLangOptions().AssumeSaneOperatorNew;
DeclareGlobalAllocationFunction(
Context.DeclarationNames.getCXXOperatorName(OO_New),
VoidPtr, SizeT, AssumeSaneOperatorNew);
DeclareGlobalAllocationFunction(
Context.DeclarationNames.getCXXOperatorName(OO_Array_New),
VoidPtr, SizeT, AssumeSaneOperatorNew);
DeclareGlobalAllocationFunction(
Context.DeclarationNames.getCXXOperatorName(OO_Delete),
Context.VoidTy, VoidPtr);
DeclareGlobalAllocationFunction(
Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete),
Context.VoidTy, VoidPtr);
}
/// DeclareGlobalAllocationFunction - Declares a single implicit global
/// allocation function if it doesn't already exist.
void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
QualType Return, QualType Argument,
bool AddMallocAttr) {
DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
// Check if this function is already declared.
{
DeclContext::lookup_iterator Alloc, AllocEnd;
for (llvm::tie(Alloc, AllocEnd) = GlobalCtx->lookup(Name);
Alloc != AllocEnd; ++Alloc) {
// Only look at non-template functions, as it is the predefined,
// non-templated allocation function we are trying to declare here.
if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
QualType InitialParamType =
Context.getCanonicalType(
Func->getParamDecl(0)->getType().getUnqualifiedType());
// FIXME: Do we need to check for default arguments here?
if (Func->getNumParams() == 1 && InitialParamType == Argument)
return;
}
}
}
QualType BadAllocType;
bool HasBadAllocExceptionSpec
= (Name.getCXXOverloadedOperator() == OO_New ||
Name.getCXXOverloadedOperator() == OO_Array_New);
if (HasBadAllocExceptionSpec) {
assert(StdBadAlloc && "Must have std::bad_alloc declared");
BadAllocType = Context.getTypeDeclType(StdBadAlloc);
}
QualType FnType = Context.getFunctionType(Return, &Argument, 1, false, 0,
true, false,
HasBadAllocExceptionSpec? 1 : 0,
&BadAllocType, false, CC_Default);
FunctionDecl *Alloc =
FunctionDecl::Create(Context, GlobalCtx, SourceLocation(), Name,
FnType, /*TInfo=*/0, FunctionDecl::None, false, true);
Alloc->setImplicit();
if (AddMallocAttr)
Alloc->addAttr(::new (Context) MallocAttr());
ParmVarDecl *Param = ParmVarDecl::Create(Context, Alloc, SourceLocation(),
0, Argument, /*TInfo=*/0,
VarDecl::None, 0);
Alloc->setParams(&Param, 1);
// FIXME: Also add this declaration to the IdentifierResolver, but
// make sure it is at the end of the chain to coincide with the
// global scope.
((DeclContext *)TUScope->getEntity())->addDecl(Alloc);
}
bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
DeclarationName Name,
FunctionDecl* &Operator) {
LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
// Try to find operator delete/operator delete[] in class scope.
LookupQualifiedName(Found, RD);
if (Found.isAmbiguous())
return true;
for (LookupResult::iterator F = Found.begin(), FEnd = Found.end();
F != FEnd; ++F) {
if (CXXMethodDecl *Delete = dyn_cast<CXXMethodDecl>(*F))
if (Delete->isUsualDeallocationFunction()) {
Operator = Delete;
return false;
}
}
// We did find operator delete/operator delete[] declarations, but
// none of them were suitable.
if (!Found.empty()) {
Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
<< Name << RD;
for (LookupResult::iterator F = Found.begin(), FEnd = Found.end();
F != FEnd; ++F) {
Diag((*F)->getLocation(),
diag::note_delete_member_function_declared_here)
<< Name;
}
return true;
}
// Look for a global declaration.
DeclareGlobalNewDelete();
DeclContext *TUDecl = Context.getTranslationUnitDecl();
CXXNullPtrLiteralExpr Null(Context.VoidPtrTy, SourceLocation());
Expr* DeallocArgs[1];
DeallocArgs[0] = &Null;
if (FindAllocationOverload(StartLoc, SourceRange(), Name,
DeallocArgs, 1, TUDecl, /*AllowMissing=*/false,
Operator))
return true;
assert(Operator && "Did not find a deallocation function!");
return false;
}
/// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
/// @code ::delete ptr; @endcode
/// or
/// @code delete [] ptr; @endcode
Action::OwningExprResult
Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
bool ArrayForm, ExprArg Operand) {
// C++ [expr.delete]p1:
// The operand shall have a pointer type, or a class type having a single
// conversion function to a pointer type. The result has type void.
//
// DR599 amends "pointer type" to "pointer to object type" in both cases.
FunctionDecl *OperatorDelete = 0;
Expr *Ex = (Expr *)Operand.get();
if (!Ex->isTypeDependent()) {
QualType Type = Ex->getType();
if (const RecordType *Record = Type->getAs<RecordType>()) {
llvm::SmallVector<CXXConversionDecl *, 4> ObjectPtrConversions;
CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
const UnresolvedSetImpl *Conversions = RD->getVisibleConversionFunctions();
for (UnresolvedSetImpl::iterator I = Conversions->begin(),
E = Conversions->end(); I != E; ++I) {
// Skip over templated conversion functions; they aren't considered.
if (isa<FunctionTemplateDecl>(*I))
continue;
CXXConversionDecl *Conv = cast<CXXConversionDecl>(*I);
QualType ConvType = Conv->getConversionType().getNonReferenceType();
if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
if (ConvPtrType->getPointeeType()->isObjectType())
ObjectPtrConversions.push_back(Conv);
}
if (ObjectPtrConversions.size() == 1) {
// We have a single conversion to a pointer-to-object type. Perform
// that conversion.
Operand.release();
if (!PerformImplicitConversion(Ex,
ObjectPtrConversions.front()->getConversionType(),
AA_Converting)) {
Operand = Owned(Ex);
Type = Ex->getType();
}
}
else if (ObjectPtrConversions.size() > 1) {
Diag(StartLoc, diag::err_ambiguous_delete_operand)
<< Type << Ex->getSourceRange();
for (unsigned i= 0; i < ObjectPtrConversions.size(); i++) {
CXXConversionDecl *Conv = ObjectPtrConversions[i];
NoteOverloadCandidate(Conv);
}
return ExprError();
}
}
if (!Type->isPointerType())
return ExprError(Diag(StartLoc, diag::err_delete_operand)
<< Type << Ex->getSourceRange());
QualType Pointee = Type->getAs<PointerType>()->getPointeeType();
if (Pointee->isFunctionType() || Pointee->isVoidType())
return ExprError(Diag(StartLoc, diag::err_delete_operand)
<< Type << Ex->getSourceRange());
else if (!Pointee->isDependentType() &&
RequireCompleteType(StartLoc, Pointee,
PDiag(diag::warn_delete_incomplete)
<< Ex->getSourceRange()))
return ExprError();
// C++ [expr.delete]p2:
// [Note: a pointer to a const type can be the operand of a
// delete-expression; it is not necessary to cast away the constness
// (5.2.11) of the pointer expression before it is used as the operand
// of the delete-expression. ]
ImpCastExprToType(Ex, Context.getPointerType(Context.VoidTy),
CastExpr::CK_NoOp);
// Update the operand.
Operand.take();
Operand = ExprArg(*this, Ex);
DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
ArrayForm ? OO_Array_Delete : OO_Delete);
if (const RecordType *RT = Pointee->getAs<RecordType>()) {
CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
if (!UseGlobal &&
FindDeallocationFunction(StartLoc, RD, DeleteName, OperatorDelete))
return ExprError();
if (!RD->hasTrivialDestructor())
if (const CXXDestructorDecl *Dtor = RD->getDestructor(Context))
MarkDeclarationReferenced(StartLoc,
const_cast<CXXDestructorDecl*>(Dtor));
}
if (!OperatorDelete) {
// Look for a global declaration.
DeclareGlobalNewDelete();
DeclContext *TUDecl = Context.getTranslationUnitDecl();
if (FindAllocationOverload(StartLoc, SourceRange(), DeleteName,
&Ex, 1, TUDecl, /*AllowMissing=*/false,
OperatorDelete))
return ExprError();
}
// FIXME: Check access and ambiguity of operator delete and destructor.
}
Operand.release();
return Owned(new (Context) CXXDeleteExpr(Context.VoidTy, UseGlobal, ArrayForm,
OperatorDelete, Ex, StartLoc));
}
/// \brief Check the use of the given variable as a C++ condition in an if,
/// while, do-while, or switch statement.
Action::OwningExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar) {
QualType T = ConditionVar->getType();
// C++ [stmt.select]p2:
// The declarator shall not specify a function or an array.
if (T->isFunctionType())
return ExprError(Diag(ConditionVar->getLocation(),
diag::err_invalid_use_of_function_type)
<< ConditionVar->getSourceRange());
else if (T->isArrayType())
return ExprError(Diag(ConditionVar->getLocation(),
diag::err_invalid_use_of_array_type)
<< ConditionVar->getSourceRange());
return Owned(DeclRefExpr::Create(Context, 0, SourceRange(), ConditionVar,
ConditionVar->getLocation(),
ConditionVar->getType().getNonReferenceType()));
}
/// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
bool Sema::CheckCXXBooleanCondition(Expr *&CondExpr) {
// C++ 6.4p4:
// The value of a condition that is an initialized declaration in a statement
// other than a switch statement is the value of the declared variable
// implicitly converted to type bool. If that conversion is ill-formed, the
// program is ill-formed.
// The value of a condition that is an expression is the value of the
// expression, implicitly converted to bool.
//
return PerformContextuallyConvertToBool(CondExpr);
}
/// Helper function to determine whether this is the (deprecated) C++
/// conversion from a string literal to a pointer to non-const char or
/// non-const wchar_t (for narrow and wide string literals,
/// respectively).
bool
Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) {
// Look inside the implicit cast, if it exists.
if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
From = Cast->getSubExpr();
// A string literal (2.13.4) that is not a wide string literal can
// be converted to an rvalue of type "pointer to char"; a wide
// string literal can be converted to an rvalue of type "pointer
// to wchar_t" (C++ 4.2p2).
if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From))
if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
if (const BuiltinType *ToPointeeType
= ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
// This conversion is considered only when there is an
// explicit appropriate pointer target type (C++ 4.2p2).
if (!ToPtrType->getPointeeType().hasQualifiers() &&
((StrLit->isWide() && ToPointeeType->isWideCharType()) ||
(!StrLit->isWide() &&
(ToPointeeType->getKind() == BuiltinType::Char_U ||
ToPointeeType->getKind() == BuiltinType::Char_S))))
return true;
}
return false;
}
/// PerformImplicitConversion - Perform an implicit conversion of the
/// expression From to the type ToType. Returns true if there was an
/// error, false otherwise. The expression From is replaced with the
/// converted expression. Flavor is the kind of conversion we're
/// performing, used in the error message. If @p AllowExplicit,
/// explicit user-defined conversions are permitted. @p Elidable should be true
/// when called for copies which may be elided (C++ 12.8p15). C++0x overload
/// resolution works differently in that case.
bool
Sema::PerformImplicitConversion(Expr *&From, QualType ToType,
AssignmentAction Action, bool AllowExplicit,
bool Elidable) {
ImplicitConversionSequence ICS;
return PerformImplicitConversion(From, ToType, Action, AllowExplicit,
Elidable, ICS);
}
bool
Sema::PerformImplicitConversion(Expr *&From, QualType ToType,
AssignmentAction Action, bool AllowExplicit,
bool Elidable,
ImplicitConversionSequence& ICS) {
ICS.setBad();
ICS.Bad.init(BadConversionSequence::no_conversion, From, ToType);
if (Elidable && getLangOptions().CPlusPlus0x) {
ICS = TryImplicitConversion(From, ToType,
/*SuppressUserConversions=*/false,
AllowExplicit,
/*ForceRValue=*/true,
/*InOverloadResolution=*/false);
}
if (ICS.isBad()) {
ICS = TryImplicitConversion(From, ToType,
/*SuppressUserConversions=*/false,
AllowExplicit,
/*ForceRValue=*/false,
/*InOverloadResolution=*/false);
}
return PerformImplicitConversion(From, ToType, ICS, Action);
}
/// PerformImplicitConversion - Perform an implicit conversion of the
/// expression From to the type ToType using the pre-computed implicit
/// conversion sequence ICS. Returns true if there was an error, false
/// otherwise. The expression From is replaced with the converted
/// expression. Action is the kind of conversion we're performing,
/// used in the error message.
bool
Sema::PerformImplicitConversion(Expr *&From, QualType ToType,
const ImplicitConversionSequence &ICS,
AssignmentAction Action, bool IgnoreBaseAccess) {
switch (ICS.getKind()) {
case ImplicitConversionSequence::StandardConversion:
if (PerformImplicitConversion(From, ToType, ICS.Standard, Action,
IgnoreBaseAccess))
return true;
break;
case ImplicitConversionSequence::UserDefinedConversion: {
FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
CastExpr::CastKind CastKind = CastExpr::CK_Unknown;
QualType BeforeToType;
if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
CastKind = CastExpr::CK_UserDefinedConversion;
// If the user-defined conversion is specified by a conversion function,
// the initial standard conversion sequence converts the source type to
// the implicit object parameter of the conversion function.
BeforeToType = Context.getTagDeclType(Conv->getParent());
} else if (const CXXConstructorDecl *Ctor =
dyn_cast<CXXConstructorDecl>(FD)) {
CastKind = CastExpr::CK_ConstructorConversion;
// Do no conversion if dealing with ... for the first conversion.
if (!ICS.UserDefined.EllipsisConversion) {
// If the user-defined conversion is specified by a constructor, the
// initial standard conversion sequence converts the source type to the
// type required by the argument of the constructor
BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
}
}
else
assert(0 && "Unknown conversion function kind!");
// Whatch out for elipsis conversion.
if (!ICS.UserDefined.EllipsisConversion) {
if (PerformImplicitConversion(From, BeforeToType,
ICS.UserDefined.Before, AA_Converting,
IgnoreBaseAccess))
return true;
}
OwningExprResult CastArg
= BuildCXXCastArgument(From->getLocStart(),
ToType.getNonReferenceType(),
CastKind, cast<CXXMethodDecl>(FD),
Owned(From));
if (CastArg.isInvalid())
return true;
From = CastArg.takeAs<Expr>();
return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
AA_Converting, IgnoreBaseAccess);
}
case ImplicitConversionSequence::AmbiguousConversion:
DiagnoseAmbiguousConversion(ICS, From->getExprLoc(),
PDiag(diag::err_typecheck_ambiguous_condition)
<< From->getSourceRange());
return true;
case ImplicitConversionSequence::EllipsisConversion:
assert(false && "Cannot perform an ellipsis conversion");
return false;
case ImplicitConversionSequence::BadConversion:
return true;
}
// Everything went well.
return false;
}
/// PerformImplicitConversion - Perform an implicit conversion of the
/// expression From to the type ToType by following the standard
/// conversion sequence SCS. Returns true if there was an error, false
/// otherwise. The expression From is replaced with the converted
/// expression. Flavor is the context in which we're performing this
/// conversion, for use in error messages.
bool
Sema::PerformImplicitConversion(Expr *&From, QualType ToType,
const StandardConversionSequence& SCS,
AssignmentAction Action, bool IgnoreBaseAccess) {
// Overall FIXME: we are recomputing too many types here and doing far too
// much extra work. What this means is that we need to keep track of more
// information that is computed when we try the implicit conversion initially,
// so that we don't need to recompute anything here.
QualType FromType = From->getType();
if (SCS.CopyConstructor) {
// FIXME: When can ToType be a reference type?
assert(!ToType->isReferenceType());
if (SCS.Second == ICK_Derived_To_Base) {
ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this);
if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor),
MultiExprArg(*this, (void **)&From, 1),
/*FIXME:ConstructLoc*/SourceLocation(),
ConstructorArgs))
return true;
OwningExprResult FromResult =
BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(),
ToType, SCS.CopyConstructor,
move_arg(ConstructorArgs));
if (FromResult.isInvalid())
return true;
From = FromResult.takeAs<Expr>();
return false;
}
OwningExprResult FromResult =
BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(),
ToType, SCS.CopyConstructor,
MultiExprArg(*this, (void**)&From, 1));
if (FromResult.isInvalid())
return true;
From = FromResult.takeAs<Expr>();
return false;
}
// Perform the first implicit conversion.
switch (SCS.First) {
case ICK_Identity:
case ICK_Lvalue_To_Rvalue:
// Nothing to do.
break;
case ICK_Array_To_Pointer:
FromType = Context.getArrayDecayedType(FromType);
ImpCastExprToType(From, FromType, CastExpr::CK_ArrayToPointerDecay);
break;
case ICK_Function_To_Pointer:
if (Context.getCanonicalType(FromType) == Context.OverloadTy) {
FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType, true);
if (!Fn)
return true;
if (DiagnoseUseOfDecl(Fn, From->getSourceRange().getBegin()))
return true;
From = FixOverloadedFunctionReference(From, Fn);
FromType = From->getType();
// If there's already an address-of operator in the expression, we have
// the right type already, and the code below would just introduce an
// invalid additional pointer level.
if (FromType->isPointerType() || FromType->isMemberFunctionPointerType())
break;
}
FromType = Context.getPointerType(FromType);
ImpCastExprToType(From, FromType, CastExpr::CK_FunctionToPointerDecay);
break;
default:
assert(false && "Improper first standard conversion");
break;
}
// Perform the second implicit conversion
switch (SCS.Second) {
case ICK_Identity:
// If both sides are functions (or pointers/references to them), there could
// be incompatible exception declarations.
if (CheckExceptionSpecCompatibility(From, ToType))
return true;
// Nothing else to do.
break;
case ICK_NoReturn_Adjustment:
// If both sides are functions (or pointers/references to them), there could
// be incompatible exception declarations.
if (CheckExceptionSpecCompatibility(From, ToType))
return true;
ImpCastExprToType(From, Context.getNoReturnType(From->getType(), false),
CastExpr::CK_NoOp);
break;
case ICK_Integral_Promotion:
case ICK_Integral_Conversion:
ImpCastExprToType(From, ToType, CastExpr::CK_IntegralCast);
break;
case ICK_Floating_Promotion:
case ICK_Floating_Conversion:
ImpCastExprToType(From, ToType, CastExpr::CK_FloatingCast);
break;
case ICK_Complex_Promotion:
case ICK_Complex_Conversion:
ImpCastExprToType(From, ToType, CastExpr::CK_Unknown);
break;
case ICK_Floating_Integral:
if (ToType->isFloatingType())
ImpCastExprToType(From, ToType, CastExpr::CK_IntegralToFloating);
else
ImpCastExprToType(From, ToType, CastExpr::CK_FloatingToIntegral);
break;
case ICK_Complex_Real:
ImpCastExprToType(From, ToType, CastExpr::CK_Unknown);
break;
case ICK_Compatible_Conversion:
ImpCastExprToType(From, ToType, CastExpr::CK_NoOp);
break;
case ICK_Pointer_Conversion: {
if (SCS.IncompatibleObjC) {
// Diagnose incompatible Objective-C conversions
Diag(From->getSourceRange().getBegin(),
diag::ext_typecheck_convert_incompatible_pointer)
<< From->getType() << ToType << Action
<< From->getSourceRange();
}
CastExpr::CastKind Kind = CastExpr::CK_Unknown;
if (CheckPointerConversion(From, ToType, Kind, IgnoreBaseAccess))
return true;
ImpCastExprToType(From, ToType, Kind);
break;
}
case ICK_Pointer_Member: {
CastExpr::CastKind Kind = CastExpr::CK_Unknown;
if (CheckMemberPointerConversion(From, ToType, Kind, IgnoreBaseAccess))
return true;
if (CheckExceptionSpecCompatibility(From, ToType))
return true;
ImpCastExprToType(From, ToType, Kind);
break;
}
case ICK_Boolean_Conversion: {
CastExpr::CastKind Kind = CastExpr::CK_Unknown;
if (FromType->isMemberPointerType())
Kind = CastExpr::CK_MemberPointerToBoolean;
ImpCastExprToType(From, Context.BoolTy, Kind);
break;
}
case ICK_Derived_To_Base:
if (CheckDerivedToBaseConversion(From->getType(),
ToType.getNonReferenceType(),
From->getLocStart(),
From->getSourceRange(),
IgnoreBaseAccess))
return true;
ImpCastExprToType(From, ToType.getNonReferenceType(),
CastExpr::CK_DerivedToBase);
break;
default:
assert(false && "Improper second standard conversion");
break;
}
switch (SCS.Third) {
case ICK_Identity:
// Nothing to do.
break;
case ICK_Qualification:
// FIXME: Not sure about lvalue vs rvalue here in the presence of rvalue
// references.
ImpCastExprToType(From, ToType.getNonReferenceType(),
CastExpr::CK_NoOp,
ToType->isLValueReferenceType());
break;
default:
assert(false && "Improper second standard conversion");
break;
}
return false;
}
Sema::OwningExprResult Sema::ActOnUnaryTypeTrait(UnaryTypeTrait OTT,
SourceLocation KWLoc,
SourceLocation LParen,
TypeTy *Ty,
SourceLocation RParen) {
QualType T = GetTypeFromParser(Ty);
// According to http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
// all traits except __is_class, __is_enum and __is_union require a the type
// to be complete.
if (OTT != UTT_IsClass && OTT != UTT_IsEnum && OTT != UTT_IsUnion) {
if (RequireCompleteType(KWLoc, T,
diag::err_incomplete_type_used_in_type_trait_expr))
return ExprError();
}
// There is no point in eagerly computing the value. The traits are designed
// to be used from type trait templates, so Ty will be a template parameter
// 99% of the time.
return Owned(new (Context) UnaryTypeTraitExpr(KWLoc, OTT, T,
RParen, Context.BoolTy));
}
QualType Sema::CheckPointerToMemberOperands(
Expr *&lex, Expr *&rex, SourceLocation Loc, bool isIndirect) {
const char *OpSpelling = isIndirect ? "->*" : ".*";
// C++ 5.5p2
// The binary operator .* [p3: ->*] binds its second operand, which shall
// be of type "pointer to member of T" (where T is a completely-defined
// class type) [...]
QualType RType = rex->getType();
const MemberPointerType *MemPtr = RType->getAs<MemberPointerType>();
if (!MemPtr) {
Diag(Loc, diag::err_bad_memptr_rhs)
<< OpSpelling << RType << rex->getSourceRange();
return QualType();
}
QualType Class(MemPtr->getClass(), 0);
// C++ 5.5p2
// [...] to its first operand, which shall be of class T or of a class of
// which T is an unambiguous and accessible base class. [p3: a pointer to
// such a class]
QualType LType = lex->getType();
if (isIndirect) {
if (const PointerType *Ptr = LType->getAs<PointerType>())
LType = Ptr->getPointeeType().getNonReferenceType();
else {
Diag(Loc, diag::err_bad_memptr_lhs)
<< OpSpelling << 1 << LType
<< CodeModificationHint::CreateReplacement(SourceRange(Loc), ".*");
return QualType();
}
}
if (!Context.hasSameUnqualifiedType(Class, LType)) {
CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/false,
/*DetectVirtual=*/false);
// FIXME: Would it be useful to print full ambiguity paths, or is that
// overkill?
if (!IsDerivedFrom(LType, Class, Paths) ||
Paths.isAmbiguous(Context.getCanonicalType(Class))) {
Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling
<< (int)isIndirect << lex->getType();
return QualType();
}
// Cast LHS to type of use.
QualType UseType = isIndirect ? Context.getPointerType(Class) : Class;
bool isLValue = !isIndirect && lex->isLvalue(Context) == Expr::LV_Valid;
ImpCastExprToType(lex, UseType, CastExpr::CK_DerivedToBase, isLValue);
}
if (isa<CXXZeroInitValueExpr>(rex->IgnoreParens())) {
// Diagnose use of pointer-to-member type which when used as
// the functional cast in a pointer-to-member expression.
Diag(Loc, diag::err_pointer_to_member_type) << isIndirect;
return QualType();
}
// C++ 5.5p2
// The result is an object or a function of the type specified by the
// second operand.
// The cv qualifiers are the union of those in the pointer and the left side,
// in accordance with 5.5p5 and 5.2.5.
// FIXME: This returns a dereferenced member function pointer as a normal
// function type. However, the only operation valid on such functions is
// calling them. There's also a GCC extension to get a function pointer to the
// thing, which is another complication, because this type - unlike the type
// that is the result of this expression - takes the class as the first
// argument.
// We probably need a "MemberFunctionClosureType" or something like that.
QualType Result = MemPtr->getPointeeType();
Result = Context.getCVRQualifiedType(Result, LType.getCVRQualifiers());
return Result;
}
/// \brief Get the target type of a standard or user-defined conversion.
static QualType TargetType(const ImplicitConversionSequence &ICS) {
switch (ICS.getKind()) {
case ImplicitConversionSequence::StandardConversion:
return ICS.Standard.getToType(2);
case ImplicitConversionSequence::UserDefinedConversion:
return ICS.UserDefined.After.getToType(2);
case ImplicitConversionSequence::AmbiguousConversion:
return ICS.Ambiguous.getToType();
case ImplicitConversionSequence::EllipsisConversion:
case ImplicitConversionSequence::BadConversion:
llvm_unreachable("function not valid for ellipsis or bad conversions");
}
return QualType(); // silence warnings
}
/// \brief Try to convert a type to another according to C++0x 5.16p3.
///
/// This is part of the parameter validation for the ? operator. If either
/// value operand is a class type, the two operands are attempted to be
/// converted to each other. This function does the conversion in one direction.
/// It emits a diagnostic and returns true only if it finds an ambiguous
/// conversion.
static bool TryClassUnification(Sema &Self, Expr *From, Expr *To,
SourceLocation QuestionLoc,
ImplicitConversionSequence &ICS) {
// C++0x 5.16p3
// The process for determining whether an operand expression E1 of type T1
// can be converted to match an operand expression E2 of type T2 is defined
// as follows:
// -- If E2 is an lvalue:
if (To->isLvalue(Self.Context) == Expr::LV_Valid) {
// E1 can be converted to match E2 if E1 can be implicitly converted to
// type "lvalue reference to T2", subject to the constraint that in the
// conversion the reference must bind directly to E1.
if (!Self.CheckReferenceInit(From,
Self.Context.getLValueReferenceType(To->getType()),
To->getLocStart(),
/*SuppressUserConversions=*/false,
/*AllowExplicit=*/false,
/*ForceRValue=*/false,
&ICS))
{
assert((ICS.isStandard() || ICS.isUserDefined()) &&
"expected a definite conversion");
bool DirectBinding =
ICS.isStandard() ? ICS.Standard.DirectBinding
: ICS.UserDefined.After.DirectBinding;
if (DirectBinding)
return false;
}
}
ICS.setBad();
// -- If E2 is an rvalue, or if the conversion above cannot be done:
// -- if E1 and E2 have class type, and the underlying class types are
// the same or one is a base class of the other:
QualType FTy = From->getType();
QualType TTy = To->getType();
const RecordType *FRec = FTy->getAs<RecordType>();
const RecordType *TRec = TTy->getAs<RecordType>();
bool FDerivedFromT = FRec && TRec && Self.IsDerivedFrom(FTy, TTy);
if (FRec && TRec && (FRec == TRec ||
FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) {
// E1 can be converted to match E2 if the class of T2 is the
// same type as, or a base class of, the class of T1, and
// [cv2 > cv1].
if ((FRec == TRec || FDerivedFromT) && TTy.isAtLeastAsQualifiedAs(FTy)) {
// Could still fail if there's no copy constructor.
// FIXME: Is this a hard error then, or just a conversion failure? The
// standard doesn't say.
ICS = Self.TryCopyInitialization(From, TTy,
/*SuppressUserConversions=*/false,
/*ForceRValue=*/false,
/*InOverloadResolution=*/false);
}
} else {
// -- Otherwise: E1 can be converted to match E2 if E1 can be
// implicitly converted to the type that expression E2 would have
// if E2 were converted to an rvalue.
// First find the decayed type.
if (TTy->isFunctionType())
TTy = Self.Context.getPointerType(TTy);
else if (TTy->isArrayType())
TTy = Self.Context.getArrayDecayedType(TTy);
// Now try the implicit conversion.
// FIXME: This doesn't detect ambiguities.
ICS = Self.TryImplicitConversion(From, TTy,
/*SuppressUserConversions=*/false,
/*AllowExplicit=*/false,
/*ForceRValue=*/false,
/*InOverloadResolution=*/false);
}
return false;
}
/// \brief Try to find a common type for two according to C++0x 5.16p5.
///
/// This is part of the parameter validation for the ? operator. If either
/// value operand is a class type, overload resolution is used to find a
/// conversion to a common type.
static bool FindConditionalOverload(Sema &Self, Expr *&LHS, Expr *&RHS,
SourceLocation Loc) {
Expr *Args[2] = { LHS, RHS };
OverloadCandidateSet CandidateSet(Loc);
Self.AddBuiltinOperatorCandidates(OO_Conditional, Loc, Args, 2, CandidateSet);
OverloadCandidateSet::iterator Best;
switch (Self.BestViableFunction(CandidateSet, Loc, Best)) {
case OR_Success:
// We found a match. Perform the conversions on the arguments and move on.
if (Self.PerformImplicitConversion(LHS, Best->BuiltinTypes.ParamTypes[0],
Best->Conversions[0], Sema::AA_Converting) ||
Self.PerformImplicitConversion(RHS, Best->BuiltinTypes.ParamTypes[1],
Best->Conversions[1], Sema::AA_Converting))
break;
return false;
case OR_No_Viable_Function:
Self.Diag(Loc, diag::err_typecheck_cond_incompatible_operands)
<< LHS->getType() << RHS->getType()
<< LHS->getSourceRange() << RHS->getSourceRange();
return true;
case OR_Ambiguous:
Self.Diag(Loc, diag::err_conditional_ambiguous_ovl)
<< LHS->getType() << RHS->getType()
<< LHS->getSourceRange() << RHS->getSourceRange();
// FIXME: Print the possible common types by printing the return types of
// the viable candidates.
break;
case OR_Deleted:
assert(false && "Conditional operator has only built-in overloads");
break;
}
return true;
}
/// \brief Perform an "extended" implicit conversion as returned by
/// TryClassUnification.
///
/// TryClassUnification generates ICSs that include reference bindings.
/// PerformImplicitConversion is not suitable for this; it chokes if the
/// second part of a standard conversion is ICK_DerivedToBase. This function
/// handles the reference binding specially.
static bool ConvertForConditional(Sema &Self, Expr *&E,
const ImplicitConversionSequence &ICS) {
if (ICS.isStandard() && ICS.Standard.ReferenceBinding) {
assert(ICS.Standard.DirectBinding &&
"TryClassUnification should never generate indirect ref bindings");
// FIXME: CheckReferenceInit should be able to reuse the ICS instead of
// redoing all the work.
return Self.CheckReferenceInit(E, Self.Context.getLValueReferenceType(
TargetType(ICS)),
/*FIXME:*/E->getLocStart(),
/*SuppressUserConversions=*/false,
/*AllowExplicit=*/false,
/*ForceRValue=*/false);
}
if (ICS.isUserDefined() && ICS.UserDefined.After.ReferenceBinding) {
assert(ICS.UserDefined.After.DirectBinding &&
"TryClassUnification should never generate indirect ref bindings");
return Self.CheckReferenceInit(E, Self.Context.getLValueReferenceType(
TargetType(ICS)),
/*FIXME:*/E->getLocStart(),
/*SuppressUserConversions=*/false,
/*AllowExplicit=*/false,
/*ForceRValue=*/false);
}
if (Self.PerformImplicitConversion(E, TargetType(ICS), ICS, Sema::AA_Converting))
return true;
return false;
}
/// \brief Check the operands of ?: under C++ semantics.
///
/// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y
/// extension. In this case, LHS == Cond. (But they're not aliases.)
QualType Sema::CXXCheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS,
SourceLocation QuestionLoc) {
// FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++
// interface pointers.
// C++0x 5.16p1
// The first expression is contextually converted to bool.
if (!Cond->isTypeDependent()) {
if (CheckCXXBooleanCondition(Cond))
return QualType();
}
// Either of the arguments dependent?
if (LHS->isTypeDependent() || RHS->isTypeDependent())
return Context.DependentTy;
CheckSignCompare(LHS, RHS, QuestionLoc, diag::warn_mixed_sign_conditional);
// C++0x 5.16p2
// If either the second or the third operand has type (cv) void, ...
QualType LTy = LHS->getType();
QualType RTy = RHS->getType();
bool LVoid = LTy->isVoidType();
bool RVoid = RTy->isVoidType();
if (LVoid || RVoid) {
// ... then the [l2r] conversions are performed on the second and third
// operands ...
DefaultFunctionArrayLvalueConversion(LHS);
DefaultFunctionArrayLvalueConversion(RHS);
LTy = LHS->getType();
RTy = RHS->getType();
// ... and one of the following shall hold:
// -- The second or the third operand (but not both) is a throw-
// expression; the result is of the type of the other and is an rvalue.
bool LThrow = isa<CXXThrowExpr>(LHS);
bool RThrow = isa<CXXThrowExpr>(RHS);
if (LThrow && !RThrow)
return RTy;
if (RThrow && !LThrow)
return LTy;
// -- Both the second and third operands have type void; the result is of
// type void and is an rvalue.
if (LVoid && RVoid)
return Context.VoidTy;
// Neither holds, error.
Diag(QuestionLoc, diag::err_conditional_void_nonvoid)
<< (LVoid ? RTy : LTy) << (LVoid ? 0 : 1)
<< LHS->getSourceRange() << RHS->getSourceRange();
return QualType();
}
// Neither is void.
// C++0x 5.16p3
// Otherwise, if the second and third operand have different types, and
// either has (cv) class type, and attempt is made to convert each of those
// operands to the other.
if (Context.getCanonicalType(LTy) != Context.getCanonicalType(RTy) &&
(LTy->isRecordType() || RTy->isRecordType())) {
ImplicitConversionSequence ICSLeftToRight, ICSRightToLeft;
// These return true if a single direction is already ambiguous.
if (TryClassUnification(*this, LHS, RHS, QuestionLoc, ICSLeftToRight))
return QualType();
if (TryClassUnification(*this, RHS, LHS, QuestionLoc, ICSRightToLeft))
return QualType();
bool HaveL2R = !ICSLeftToRight.isBad();
bool HaveR2L = !ICSRightToLeft.isBad();
// If both can be converted, [...] the program is ill-formed.
if (HaveL2R && HaveR2L) {
Diag(QuestionLoc, diag::err_conditional_ambiguous)
<< LTy << RTy << LHS->getSourceRange() << RHS->getSourceRange();
return QualType();
}
// If exactly one conversion is possible, that conversion is applied to
// the chosen operand and the converted operands are used in place of the
// original operands for the remainder of this section.
if (HaveL2R) {
if (ConvertForConditional(*this, LHS, ICSLeftToRight))
return QualType();
LTy = LHS->getType();
} else if (HaveR2L) {
if (ConvertForConditional(*this, RHS, ICSRightToLeft))
return QualType();
RTy = RHS->getType();
}
}
// C++0x 5.16p4
// If the second and third operands are lvalues and have the same type,
// the result is of that type [...]
bool Same = Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy);
if (Same && LHS->isLvalue(Context) == Expr::LV_Valid &&
RHS->isLvalue(Context) == Expr::LV_Valid)
return LTy;
// C++0x 5.16p5
// Otherwise, the result is an rvalue. If the second and third operands
// do not have the same type, and either has (cv) class type, ...
if (!Same && (LTy->isRecordType() || RTy->isRecordType())) {
// ... overload resolution is used to determine the conversions (if any)
// to be applied to the operands. If the overload resolution fails, the
// program is ill-formed.
if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc))
return QualType();
}
// C++0x 5.16p6
// LValue-to-rvalue, array-to-pointer, and function-to-pointer standard
// conversions are performed on the second and third operands.
DefaultFunctionArrayLvalueConversion(LHS);
DefaultFunctionArrayLvalueConversion(RHS);
LTy = LHS->getType();
RTy = RHS->getType();
// After those conversions, one of the following shall hold:
// -- The second and third operands have the same type; the result
// is of that type.
if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy))
return LTy;
// -- The second and third operands have arithmetic or enumeration type;
// the usual arithmetic conversions are performed to bring them to a
// common type, and the result is of that type.
if (LTy->isArithmeticType() && RTy->isArithmeticType()) {
UsualArithmeticConversions(LHS, RHS);
return LHS->getType();
}
// -- The second and third operands have pointer type, or one has pointer
// type and the other is a null pointer constant; pointer conversions
// and qualification conversions are performed to bring them to their
// composite pointer type. The result is of the composite pointer type.
// -- The second and third operands have pointer to member type, or one has
// pointer to member type and the other is a null pointer constant;
// pointer to member conversions and qualification conversions are
// performed to bring them to a common type, whose cv-qualification
// shall match the cv-qualification of either the second or the third
// operand. The result is of the common type.
QualType Composite = FindCompositePointerType(LHS, RHS);
if (!Composite.isNull())
return Composite;
// Similarly, attempt to find composite type of twp objective-c pointers.
Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc);
if (!Composite.isNull())
return Composite;
Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
<< LHS->getType() << RHS->getType()
<< LHS->getSourceRange() << RHS->getSourceRange();
return QualType();
}
/// \brief Find a merged pointer type and convert the two expressions to it.
///
/// This finds the composite pointer type (or member pointer type) for @p E1
/// and @p E2 according to C++0x 5.9p2. It converts both expressions to this
/// type and returns it.
/// It does not emit diagnostics.
QualType Sema::FindCompositePointerType(Expr *&E1, Expr *&E2) {
assert(getLangOptions().CPlusPlus && "This function assumes C++");
QualType T1 = E1->getType(), T2 = E2->getType();
if (!T1->isAnyPointerType() && !T1->isMemberPointerType() &&
!T2->isAnyPointerType() && !T2->isMemberPointerType())
return QualType();
// C++0x 5.9p2
// Pointer conversions and qualification conversions are performed on
// pointer operands to bring them to their composite pointer type. If
// one operand is a null pointer constant, the composite pointer type is
// the type of the other operand.
if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
if (T2->isMemberPointerType())
ImpCastExprToType(E1, T2, CastExpr::CK_NullToMemberPointer);
else
ImpCastExprToType(E1, T2, CastExpr::CK_IntegralToPointer);
return T2;
}
if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
if (T1->isMemberPointerType())
ImpCastExprToType(E2, T1, CastExpr::CK_NullToMemberPointer);
else
ImpCastExprToType(E2, T1, CastExpr::CK_IntegralToPointer);
return T1;
}
// Now both have to be pointers or member pointers.
if ((!T1->isPointerType() && !T1->isMemberPointerType()) ||
(!T2->isPointerType() && !T2->isMemberPointerType()))
return QualType();
// Otherwise, of one of the operands has type "pointer to cv1 void," then
// the other has type "pointer to cv2 T" and the composite pointer type is
// "pointer to cv12 void," where cv12 is the union of cv1 and cv2.
// Otherwise, the composite pointer type is a pointer type similar to the
// type of one of the operands, with a cv-qualification signature that is
// the union of the cv-qualification signatures of the operand types.
// In practice, the first part here is redundant; it's subsumed by the second.
// What we do here is, we build the two possible composite types, and try the
// conversions in both directions. If only one works, or if the two composite
// types are the same, we have succeeded.
// FIXME: extended qualifiers?
typedef llvm::SmallVector<unsigned, 4> QualifierVector;
QualifierVector QualifierUnion;
typedef llvm::SmallVector<std::pair<const Type *, const Type *>, 4>
ContainingClassVector;
ContainingClassVector MemberOfClass;
QualType Composite1 = Context.getCanonicalType(T1),
Composite2 = Context.getCanonicalType(T2);
do {
const PointerType *Ptr1, *Ptr2;
if ((Ptr1 = Composite1->getAs<PointerType>()) &&
(Ptr2 = Composite2->getAs<PointerType>())) {
Composite1 = Ptr1->getPointeeType();
Composite2 = Ptr2->getPointeeType();
QualifierUnion.push_back(
Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
MemberOfClass.push_back(std::make_pair((const Type *)0, (const Type *)0));
continue;
}
const MemberPointerType *MemPtr1, *MemPtr2;
if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) &&
(MemPtr2 = Composite2->getAs<MemberPointerType>())) {
Composite1 = MemPtr1->getPointeeType();
Composite2 = MemPtr2->getPointeeType();
QualifierUnion.push_back(
Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(),
MemPtr2->getClass()));
continue;
}
// FIXME: block pointer types?
// Cannot unwrap any more types.
break;
} while (true);
// Rewrap the composites as pointers or member pointers with the union CVRs.
ContainingClassVector::reverse_iterator MOC
= MemberOfClass.rbegin();
for (QualifierVector::reverse_iterator
I = QualifierUnion.rbegin(),
E = QualifierUnion.rend();
I != E; (void)++I, ++MOC) {
Qualifiers Quals = Qualifiers::fromCVRMask(*I);
if (MOC->first && MOC->second) {
// Rebuild member pointer type
Composite1 = Context.getMemberPointerType(
Context.getQualifiedType(Composite1, Quals),
MOC->first);
Composite2 = Context.getMemberPointerType(
Context.getQualifiedType(Composite2, Quals),
MOC->second);
} else {
// Rebuild pointer type
Composite1
= Context.getPointerType(Context.getQualifiedType(Composite1, Quals));
Composite2
= Context.getPointerType(Context.getQualifiedType(Composite2, Quals));
}
}
ImplicitConversionSequence E1ToC1 =
TryImplicitConversion(E1, Composite1,
/*SuppressUserConversions=*/false,
/*AllowExplicit=*/false,
/*ForceRValue=*/false,
/*InOverloadResolution=*/false);
ImplicitConversionSequence E2ToC1 =
TryImplicitConversion(E2, Composite1,
/*SuppressUserConversions=*/false,
/*AllowExplicit=*/false,
/*ForceRValue=*/false,
/*InOverloadResolution=*/false);
ImplicitConversionSequence E1ToC2, E2ToC2;
E1ToC2.setBad();
E2ToC2.setBad();
if (Context.getCanonicalType(Composite1) !=
Context.getCanonicalType(Composite2)) {
E1ToC2 = TryImplicitConversion(E1, Composite2,
/*SuppressUserConversions=*/false,
/*AllowExplicit=*/false,
/*ForceRValue=*/false,
/*InOverloadResolution=*/false);
E2ToC2 = TryImplicitConversion(E2, Composite2,
/*SuppressUserConversions=*/false,
/*AllowExplicit=*/false,
/*ForceRValue=*/false,
/*InOverloadResolution=*/false);
}
bool ToC1Viable = !E1ToC1.isBad() && !E2ToC1.isBad();
bool ToC2Viable = !E1ToC2.isBad() && !E2ToC2.isBad();
if (ToC1Viable && !ToC2Viable) {
if (!PerformImplicitConversion(E1, Composite1, E1ToC1, Sema::AA_Converting) &&
!PerformImplicitConversion(E2, Composite1, E2ToC1, Sema::AA_Converting))
return Composite1;
}
if (ToC2Viable && !ToC1Viable) {
if (!PerformImplicitConversion(E1, Composite2, E1ToC2, Sema::AA_Converting) &&
!PerformImplicitConversion(E2, Composite2, E2ToC2, Sema::AA_Converting))
return Composite2;
}
return QualType();
}
Sema::OwningExprResult Sema::MaybeBindToTemporary(Expr *E) {
if (!Context.getLangOptions().CPlusPlus)
return Owned(E);
assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?");
const RecordType *RT = E->getType()->getAs<RecordType>();
if (!RT)
return Owned(E);
// If this is the result of a call expression, our source might
// actually be a reference, in which case we shouldn't bind.
if (CallExpr *CE = dyn_cast<CallExpr>(E)) {
QualType Ty = CE->getCallee()->getType();
if (const PointerType *PT = Ty->getAs<PointerType>())
Ty = PT->getPointeeType();
else if (const BlockPointerType *BPT = Ty->getAs<BlockPointerType>())
Ty = BPT->getPointeeType();
const FunctionType *FTy = Ty->getAs<FunctionType>();
if (FTy->getResultType()->isReferenceType())
return Owned(E);
}
// That should be enough to guarantee that this type is complete.
// If it has a trivial destructor, we can avoid the extra copy.
CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
if (RD->hasTrivialDestructor())
return Owned(E);
CXXTemporary *Temp = CXXTemporary::Create(Context,
RD->getDestructor(Context));
ExprTemporaries.push_back(Temp);
if (CXXDestructorDecl *Destructor =
const_cast<CXXDestructorDecl*>(RD->getDestructor(Context)))
MarkDeclarationReferenced(E->getExprLoc(), Destructor);
// FIXME: Add the temporary to the temporaries vector.
return Owned(CXXBindTemporaryExpr::Create(Context, Temp, E));
}
Expr *Sema::MaybeCreateCXXExprWithTemporaries(Expr *SubExpr) {
assert(SubExpr && "sub expression can't be null!");
unsigned FirstTemporary = ExprEvalContexts.back().NumTemporaries;
assert(ExprTemporaries.size() >= FirstTemporary);
if (ExprTemporaries.size() == FirstTemporary)
return SubExpr;
Expr *E = CXXExprWithTemporaries::Create(Context, SubExpr,
&ExprTemporaries[FirstTemporary],
ExprTemporaries.size() - FirstTemporary);
ExprTemporaries.erase(ExprTemporaries.begin() + FirstTemporary,
ExprTemporaries.end());
return E;
}
Sema::OwningExprResult
Sema::MaybeCreateCXXExprWithTemporaries(OwningExprResult SubExpr) {
if (SubExpr.isInvalid())
return ExprError();
return Owned(MaybeCreateCXXExprWithTemporaries(SubExpr.takeAs<Expr>()));
}
FullExpr Sema::CreateFullExpr(Expr *SubExpr) {
unsigned FirstTemporary = ExprEvalContexts.back().NumTemporaries;
assert(ExprTemporaries.size() >= FirstTemporary);
unsigned NumTemporaries = ExprTemporaries.size() - FirstTemporary;
CXXTemporary **Temporaries =
NumTemporaries == 0 ? 0 : &ExprTemporaries[FirstTemporary];
FullExpr E = FullExpr::Create(Context, SubExpr, Temporaries, NumTemporaries);
ExprTemporaries.erase(ExprTemporaries.begin() + FirstTemporary,
ExprTemporaries.end());
return E;
}
Sema::OwningExprResult
Sema::ActOnStartCXXMemberReference(Scope *S, ExprArg Base, SourceLocation OpLoc,
tok::TokenKind OpKind, TypeTy *&ObjectType) {
// Since this might be a postfix expression, get rid of ParenListExprs.
Base = MaybeConvertParenListExprToParenExpr(S, move(Base));
Expr *BaseExpr = (Expr*)Base.get();
assert(BaseExpr && "no record expansion");
QualType BaseType = BaseExpr->getType();
if (BaseType->isDependentType()) {
// If we have a pointer to a dependent type and are using the -> operator,
// the object type is the type that the pointer points to. We might still
// have enough information about that type to do something useful.
if (OpKind == tok::arrow)
if (const PointerType *Ptr = BaseType->getAs<PointerType>())
BaseType = Ptr->getPointeeType();
ObjectType = BaseType.getAsOpaquePtr();
return move(Base);
}
// C++ [over.match.oper]p8:
// [...] When operator->returns, the operator-> is applied to the value
// returned, with the original second operand.
if (OpKind == tok::arrow) {
// The set of types we've considered so far.
llvm::SmallPtrSet<CanQualType,8> CTypes;
llvm::SmallVector<SourceLocation, 8> Locations;
CTypes.insert(Context.getCanonicalType(BaseType));
while (BaseType->isRecordType()) {
Base = BuildOverloadedArrowExpr(S, move(Base), OpLoc);
BaseExpr = (Expr*)Base.get();
if (BaseExpr == NULL)
return ExprError();
if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(BaseExpr))
Locations.push_back(OpCall->getDirectCallee()->getLocation());
BaseType = BaseExpr->getType();
CanQualType CBaseType = Context.getCanonicalType(BaseType);
if (!CTypes.insert(CBaseType)) {
Diag(OpLoc, diag::err_operator_arrow_circular);
for (unsigned i = 0; i < Locations.size(); i++)
Diag(Locations[i], diag::note_declared_at);
return ExprError();
}
}
if (BaseType->isPointerType())
BaseType = BaseType->getPointeeType();
}
// We could end up with various non-record types here, such as extended
// vector types or Objective-C interfaces. Just return early and let
// ActOnMemberReferenceExpr do the work.
if (!BaseType->isRecordType()) {
// C++ [basic.lookup.classref]p2:
// [...] If the type of the object expression is of pointer to scalar
// type, the unqualified-id is looked up in the context of the complete
// postfix-expression.
ObjectType = 0;
return move(Base);
}
// The object type must be complete (or dependent).
if (!BaseType->isDependentType() &&
RequireCompleteType(OpLoc, BaseType,
PDiag(diag::err_incomplete_member_access)))
return ExprError();
// C++ [basic.lookup.classref]p2:
// If the id-expression in a class member access (5.2.5) is an
// unqualified-id, and the type of the object expression is of a class
// type C (or of pointer to a class type C), the unqualified-id is looked
// up in the scope of class C. [...]
ObjectType = BaseType.getAsOpaquePtr();
return move(Base);
}
CXXMemberCallExpr *Sema::BuildCXXMemberCallExpr(Expr *Exp,
CXXMethodDecl *Method) {
if (PerformObjectArgumentInitialization(Exp, Method))
assert(0 && "Calling BuildCXXMemberCallExpr with invalid call?");
MemberExpr *ME =
new (Context) MemberExpr(Exp, /*IsArrow=*/false, Method,
SourceLocation(), Method->getType());
QualType ResultType = Method->getResultType().getNonReferenceType();
MarkDeclarationReferenced(Exp->getLocStart(), Method);
CXXMemberCallExpr *CE =
new (Context) CXXMemberCallExpr(Context, ME, 0, 0, ResultType,
Exp->getLocEnd());
return CE;
}
Sema::OwningExprResult Sema::BuildCXXCastArgument(SourceLocation CastLoc,
QualType Ty,
CastExpr::CastKind Kind,
CXXMethodDecl *Method,
ExprArg Arg) {
Expr *From = Arg.takeAs<Expr>();
switch (Kind) {
default: assert(0 && "Unhandled cast kind!");
case CastExpr::CK_ConstructorConversion: {
ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this);
if (CompleteConstructorCall(cast<CXXConstructorDecl>(Method),
MultiExprArg(*this, (void **)&From, 1),
CastLoc, ConstructorArgs))
return ExprError();
OwningExprResult Result =
BuildCXXConstructExpr(CastLoc, Ty, cast<CXXConstructorDecl>(Method),
move_arg(ConstructorArgs));
if (Result.isInvalid())
return ExprError();
return MaybeBindToTemporary(Result.takeAs<Expr>());
}
case CastExpr::CK_UserDefinedConversion: {
assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
// Create an implicit call expr that calls it.
CXXMemberCallExpr *CE = BuildCXXMemberCallExpr(From, Method);
return MaybeBindToTemporary(CE);
}
}
}
Sema::OwningExprResult Sema::ActOnFinishFullExpr(ExprArg Arg) {
Expr *FullExpr = Arg.takeAs<Expr>();
if (FullExpr)
FullExpr = MaybeCreateCXXExprWithTemporaries(FullExpr);
return Owned(FullExpr);
}