/// Get the number of possible values that can be switched on for the type T.
///
/// \return - 0 if bitcount could not be determined
/// - numeric_limits<std::size_t>::max() when overflow appeared due to
/// more than 64 bits type size.
static std::size_t getNumberOfPossibleValues(QualType T,
const ASTContext &Context) {
// `isBooleanType` must come first because `bool` is an integral type as well
// and would not return 2 as result.
if (T->isBooleanType())
return 2;
else if (T->isIntegralType(Context))
return twoPow(Context.getTypeSize(T));
else
return 1;
}
static Stmt *create_OSAtomicCompareAndSwap(ASTContext &C, const FunctionDecl *D)
{
// There are exactly 3 arguments.
if (D->param_size() != 3)
return nullptr;
// Signature:
// _Bool OSAtomicCompareAndSwapPtr(void *__oldValue,
// void *__newValue,
// void * volatile *__theValue)
// Generate body:
// if (oldValue == *theValue) {
// *theValue = newValue;
// return YES;
// }
// else return NO;
QualType ResultTy = D->getReturnType();
bool isBoolean = ResultTy->isBooleanType();
if (!isBoolean && !ResultTy->isIntegralType(C))
return nullptr;
const ParmVarDecl *OldValue = D->getParamDecl(0);
QualType OldValueTy = OldValue->getType();
const ParmVarDecl *NewValue = D->getParamDecl(1);
QualType NewValueTy = NewValue->getType();
assert(OldValueTy == NewValueTy);
const ParmVarDecl *TheValue = D->getParamDecl(2);
QualType TheValueTy = TheValue->getType();
const PointerType *PT = TheValueTy->getAs<PointerType>();
if (!PT)
return nullptr;
QualType PointeeTy = PT->getPointeeType();
ASTMaker M(C);
// Construct the comparison.
Expr *Comparison =
M.makeComparison(
M.makeLvalueToRvalue(M.makeDeclRefExpr(OldValue), OldValueTy),
M.makeLvalueToRvalue(
M.makeDereference(
M.makeLvalueToRvalue(M.makeDeclRefExpr(TheValue), TheValueTy),
PointeeTy),
PointeeTy),
BO_EQ);
// Construct the body of the IfStmt.
Stmt *Stmts[2];
Stmts[0] =
M.makeAssignment(
M.makeDereference(
M.makeLvalueToRvalue(M.makeDeclRefExpr(TheValue), TheValueTy),
PointeeTy),
M.makeLvalueToRvalue(M.makeDeclRefExpr(NewValue), NewValueTy),
NewValueTy);
Expr *BoolVal = M.makeObjCBool(true);
Expr *RetVal = isBoolean ? M.makeIntegralCastToBoolean(BoolVal)
: M.makeIntegralCast(BoolVal, ResultTy);
Stmts[1] = M.makeReturn(RetVal);
CompoundStmt *Body = M.makeCompound(Stmts);
// Construct the else clause.
BoolVal = M.makeObjCBool(false);
RetVal = isBoolean ? M.makeIntegralCastToBoolean(BoolVal)
: M.makeIntegralCast(BoolVal, ResultTy);
Stmt *Else = M.makeReturn(RetVal);
/// Construct the If.
Stmt *If = new (C) IfStmt(C, SourceLocation(), false, nullptr, nullptr,
Comparison, Body, SourceLocation(), Else);
return If;
}
/// 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;
unsigned Skip = 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());
ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
Skip = 1;
}
QualType AllocType = GetTypeForDeclarator(D, /*Scope=*/0, Skip);
if (D.getInvalidType())
return ExprError();
if (CheckAllocatedType(AllocType, D))
return ExprError();
QualType ResultType = AllocType->isDependentType()
? Context.DependentTy
: 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."
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()), false))
return ExprError(Diag(ArraySize->getSourceRange().getBegin(),
diag::err_typecheck_negative_array_size)
<< ArraySize->getSourceRange());
}
}
}
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();
bool Init = ConstructorLParen.isValid();
// --- Choosing a constructor ---
// C++ 5.3.4p15
// 1) If T is a POD and there's no initializer (ConstructorLParen is invalid)
// the object is not initialized. If the object, or any part of it, is
// const-qualified, it's an error.
// 2) If T is a POD and there's an empty initializer, the object is value-
// initialized.
// 3) If T is a POD and there's one initializer argument, the object is copy-
// constructed.
// 4) If T is a POD and there's more initializer arguments, it's an error.
// 5) If T is not a POD, the initializer arguments are used as constructor
// arguments.
//
// Or by the C++0x formulation:
// 1) If there's no initializer, the object is default-initialized according
// to C++0x rules.
// 2) Otherwise, the object is direct-initialized.
CXXConstructorDecl *Constructor = 0;
Expr **ConsArgs = (Expr**)ConstructorArgs.get();
unsigned NumConsArgs = ConstructorArgs.size();
if (AllocType->isDependentType()) {
// Skip all the checks.
}
// FIXME: Should check for primitive/aggregate here, not record.
else if (const RecordType *RT = AllocType->getAsRecordType()) {
// FIXME: This is incorrect for when there is an empty initializer and
// no user-defined constructor. Must zero-initialize, not default-construct.
Constructor = PerformInitializationByConstructor(
AllocType, ConsArgs, NumConsArgs,
D.getSourceRange().getBegin(),
SourceRange(D.getSourceRange().getBegin(),
ConstructorRParen),
RT->getDecl()->getDeclName(),
NumConsArgs != 0 ? IK_Direct : IK_Default);
if (!Constructor)
return ExprError();
} else {
if (!Init) {
// FIXME: Check that no subpart is const.
if (AllocType.isConstQualified())
return ExprError(Diag(StartLoc, diag::err_new_uninitialized_const)
<< D.getSourceRange());
} else if (NumConsArgs == 0) {
// Object is value-initialized. Do nothing.
} else if (NumConsArgs == 1) {
// Object is direct-initialized.
// FIXME: WHAT DeclarationName do we pass in here?
if (CheckInitializerTypes(ConsArgs[0], AllocType, StartLoc,
DeclarationName() /*AllocType.getAsString()*/,
/*DirectInit=*/true))
return ExprError();
} else {
return ExprError(Diag(StartLoc,
diag::err_builtin_direct_init_more_than_one_arg)
<< SourceRange(ConstructorLParen, ConstructorRParen));
}
}
// FIXME: Also check that the destructor is accessible. (C++ 5.3.4p16)
PlacementArgs.release();
ConstructorArgs.release();
return Owned(new (Context) CXXNewExpr(UseGlobal, OperatorNew, PlaceArgs,
NumPlaceArgs, ParenTypeId, ArraySize, Constructor, Init,
ConsArgs, NumConsArgs, OperatorDelete, ResultType,
StartLoc, Init ? ConstructorRParen : SourceLocation()));
}
bool DeclExtractor::CheckTagDeclaration(TagDecl* NewTD,
LookupResult& Previous){
// If the decl is already known invalid, don't check it.
if (NewTD->isInvalidDecl())
return false;
IdentifierInfo* Name = NewTD->getIdentifier();
// If this is not a definition, it must have a name.
assert((Name != 0 || NewTD->isThisDeclarationADefinition()) &&
"Nameless record must be a definition!");
// Figure out the underlying type if this a enum declaration. We need to do
// this early, because it's needed to detect if this is an incompatible
// redeclaration.
TagDecl::TagKind Kind = NewTD->getTagKind();
bool Invalid = false;
assert(NewTD->getNumTemplateParameterLists() == 0
&& "Cannot handle that yet!");
bool isExplicitSpecialization = false;
if (Kind == TTK_Enum) {
EnumDecl* ED = cast<EnumDecl>(NewTD);
bool ScopedEnum = ED->isScoped();
const QualType QT = ED->getIntegerType();
if (QT.isNull() && ScopedEnum)
// No underlying type explicitly specified, or we failed to parse the
// type, default to int.
; //EnumUnderlying = m_Context->IntTy.getTypePtr();
else if (!QT.isNull()) {
// C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an
// integral type; any cv-qualification is ignored.
SourceLocation UnderlyingLoc;
TypeSourceInfo* TI = 0;
if ((TI = ED->getIntegerTypeSourceInfo()))
UnderlyingLoc = TI->getTypeLoc().getBeginLoc();
if (!QT->isDependentType() && !QT->isIntegralType(*m_Context)) {
m_Sema->Diag(UnderlyingLoc, diag::err_enum_invalid_underlying)
<< QT;
}
if (TI)
m_Sema->DiagnoseUnexpandedParameterPack(UnderlyingLoc, TI,
Sema::UPPC_FixedUnderlyingType);
}
}
DeclContext *SearchDC = m_Sema->CurContext;
DeclContext *DC = m_Sema->CurContext;
//bool isStdBadAlloc = false;
SourceLocation NameLoc = NewTD->getLocation();
// if (Name && SS.isNotEmpty()) {
// // We have a nested-name tag ('struct foo::bar').
// // Check for invalid 'foo::'.
// if (SS.isInvalid()) {
// Name = 0;
// goto CreateNewDecl;
// }
// // If this is a friend or a reference to a class in a dependent
// // context, don't try to make a decl for it.
// if (TUK == TUK_Friend || TUK == TUK_Reference) {
// DC = computeDeclContext(SS, false);
// if (!DC) {
// IsDependent = true;
// return 0;
// }
// } else {
// DC = computeDeclContext(SS, true);
// if (!DC) {
// Diag(SS.getRange().getBegin(),
// diag::err_dependent_nested_name_spec)
// << SS.getRange();
// return 0;
// }
// }
// if (RequireCompleteDeclContext(SS, DC))
// return 0;
// SearchDC = DC;
// // Look-up name inside 'foo::'.
// LookupQualifiedName(Previous, DC);
// if (Previous.isAmbiguous())
// return 0;
// if (Previous.empty()) {
// // Name lookup did not find anything. However, if the
// // nested-name-specifier refers to the current instantiation,
// // and that current instantiation has any dependent base
// // classes, we might find something at instantiation time: treat
// // this as a dependent elaborated-type-specifier.
// // But this only makes any sense for reference-like lookups.
// if (Previous.wasNotFoundInCurrentInstantiation() &&
// (TUK == TUK_Reference || TUK == TUK_Friend)) {
// IsDependent = true;
// return 0;
// }
// // A tag 'foo::bar' must already exist.
// Diag(NameLoc, diag::err_not_tag_in_scope)
// << Kind << Name << DC << SS.getRange();
// Name = 0;
// Invalid = true;
// goto CreateNewDecl;
// }
//} else
if (Name) {
// If this is a named struct, check to see if there was a previous forward
// declaration or definition.
// FIXME: We're looking into outer scopes here, even when we
// shouldn't be. Doing so can result in ambiguities that we
// shouldn't be diagnosing.
//LookupName(Previous, S);
if (Previous.isAmbiguous()) {
LookupResult::Filter F = Previous.makeFilter();
while (F.hasNext()) {
NamedDecl *ND = F.next();
if (ND->getDeclContext()->getRedeclContext() != SearchDC)
F.erase();
}
F.done();
}
// Note: there used to be some attempt at recovery here.
if (Previous.isAmbiguous()) {
return false;
}
if (!m_Sema->getLangOpts().CPlusPlus) {
// FIXME: This makes sure that we ignore the contexts associated
// with C structs, unions, and enums when looking for a matching
// tag declaration or definition. See the similar lookup tweak
// in Sema::LookupName; is there a better way to deal with this?
while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
SearchDC = SearchDC->getParent();
}
} else if (m_Sema->getScopeForContext(m_Sema->CurContext)
->isFunctionPrototypeScope()) {
// If this is an enum declaration in function prototype scope, set its
// initial context to the translation unit.
SearchDC = m_Context->getTranslationUnitDecl();
}
if (Previous.isSingleResult() &&
Previous.getFoundDecl()->isTemplateParameter()) {
// Maybe we will complain about the shadowed template parameter.
m_Sema->DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl());
// Just pretend that we didn't see the previous declaration.
Previous.clear();
}
if (m_Sema->getLangOpts().CPlusPlus && Name && DC && m_Sema->StdNamespace
&& DC->Equals(m_Sema->getStdNamespace()) && Name->isStr("bad_alloc")) {
// This is a declaration of or a reference to "std::bad_alloc".
//isStdBadAlloc = true;
if (Previous.empty() && m_Sema->StdBadAlloc) {
// std::bad_alloc has been implicitly declared (but made invisible to
// name lookup). Fill in this implicit declaration as the previous
// declaration, so that the declarations get chained appropriately.
Previous.addDecl(m_Sema->getStdBadAlloc());
}
}
if (!Previous.empty()) {
NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl();
// It's okay to have a tag decl in the same scope as a typedef
// which hides a tag decl in the same scope. Finding this
// insanity with a redeclaration lookup can only actually happen
// in C++.
//
// This is also okay for elaborated-type-specifiers, which is
// technically forbidden by the current standard but which is
// okay according to the likely resolution of an open issue;
// see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407
if (m_Sema->getLangOpts().CPlusPlus) {
if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(PrevDecl)) {
if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) {
TagDecl *Tag = TT->getDecl();
if (Tag->getDeclName() == Name &&
Tag->getDeclContext()->getRedeclContext()
->Equals(TD->getDeclContext()->getRedeclContext())) {
PrevDecl = Tag;
Previous.clear();
Previous.addDecl(Tag);
Previous.resolveKind();
}
}
}
}
if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) {
// If this is a use of a previous tag, or if the tag is already declared
// in the same scope (so that the definition/declaration completes or
// rementions the tag), reuse the decl.
if (m_Sema->isDeclInScope(PrevDecl, SearchDC,
m_Sema->getScopeForContext(m_Sema->CurContext),
isExplicitSpecialization)) {
// Make sure that this wasn't declared as an enum and now used as a
// struct or something similar.
SourceLocation KWLoc = NewTD->getLocStart();
if (!m_Sema->isAcceptableTagRedeclaration(PrevTagDecl, Kind,
NewTD->isThisDeclarationADefinition(),
KWLoc, *Name)) {
bool SafeToContinue
= (PrevTagDecl->getTagKind() != TTK_Enum && Kind != TTK_Enum);
if (SafeToContinue)
m_Sema->Diag(KWLoc, diag::err_use_with_wrong_tag)
<< Name
<< FixItHint::CreateReplacement(SourceRange(KWLoc),
PrevTagDecl->getKindName());
else
m_Sema->Diag(KWLoc, diag::err_use_with_wrong_tag) << Name;
m_Sema->Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
if (SafeToContinue)
Kind = PrevTagDecl->getTagKind();
else {
// Recover by making this an anonymous redefinition.
Name = 0;
Previous.clear();
Invalid = true;
}
}
if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) {
const EnumDecl *NewEnum = cast<EnumDecl>(NewTD);
const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl);
// All conflicts with previous declarations are recovered by
// returning the previous declaration.
if (NewEnum->isScoped() != PrevEnum->isScoped()) {
m_Sema->Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch)
<< PrevEnum->isScoped();
m_Sema->Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
return false;
}
else if (PrevEnum->isFixed()) {
QualType T = NewEnum->getIntegerType();
if (!m_Context->hasSameUnqualifiedType(T,
PrevEnum->getIntegerType())) {
m_Sema->Diag(NameLoc.isValid() ? NameLoc : KWLoc,
diag::err_enum_redeclare_type_mismatch)
<< T
<< PrevEnum->getIntegerType();
m_Sema->Diag(PrevTagDecl->getLocation(),
diag::note_previous_use);
return false;
}
}
else if (NewEnum->isFixed() != PrevEnum->isFixed()) {
m_Sema->Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch)
<< PrevEnum->isFixed();
m_Sema->Diag(PrevTagDecl->getLocation(), diag::note_previous_use);
return false;
}
}
if (!Invalid) {
// If this is a use, just return the declaration we found.
// Diagnose attempts to redefine a tag.
if (NewTD->isThisDeclarationADefinition()) {
if (TagDecl* Def = PrevTagDecl->getDefinition()) {
// If we're defining a specialization and the previous
// definition is from an implicit instantiation, don't emit an
// error here; we'll catch this in the general case below.
if (!isExplicitSpecialization ||
!isa<CXXRecordDecl>(Def) ||
cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind()
== TSK_ExplicitSpecialization) {
m_Sema->Diag(NameLoc, diag::err_redefinition) << Name;
m_Sema->Diag(Def->getLocation(),
diag::note_previous_definition);
// If this is a redefinition, recover by making this
// struct be anonymous, which will make any later
// references get the previous definition.
Name = 0;
Previous.clear();
Invalid = true;
}
} else {
// If the type is currently being defined, complain
// about a nested redefinition.
const TagType *Tag
= cast<TagType>(m_Context->getTagDeclType(PrevTagDecl));
if (Tag->isBeingDefined()) {
m_Sema->Diag(NameLoc, diag::err_nested_redefinition) << Name;
m_Sema->Diag(PrevTagDecl->getLocation(),
diag::note_previous_definition);
Name = 0;
Previous.clear();
Invalid = true;
}
}
// Okay, this is definition of a previously declared or referenced
// tag PrevDecl. We're going to create a new Decl for it.
}
}
// If we get here we have (another) forward declaration or we
// have a definition. Just create a new decl.
} else {
// If we get here, this is a definition of a new tag type in a nested
// scope, e.g. "struct foo; void bar() { struct foo; }", just create a
// new decl/type. We set PrevDecl to NULL so that the entities
// have distinct types.
Previous.clear();
}
// If we get here, we're going to create a new Decl. If PrevDecl
// is non-NULL, it's a definition of the tag declared by
// PrevDecl. If it's NULL, we have a new definition.
// Otherwise, PrevDecl is not a tag, but was found with tag
// lookup. This is only actually possible in C++, where a few
// things like templates still live in the tag namespace.
} else {
assert(m_Sema->getLangOpts().CPlusPlus);
// Diagnose if the declaration is in scope.
if (!m_Sema->isDeclInScope(PrevDecl, SearchDC,
m_Sema->getScopeForContext(m_Sema->CurContext),
isExplicitSpecialization)) {
// do nothing
// Otherwise it's a declaration. Call out a particularly common
// case here.
} else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(PrevDecl)) {
unsigned Kind = 0;
if (isa<TypeAliasDecl>(PrevDecl)) Kind = 1;
m_Sema->Diag(NameLoc, diag::err_tag_definition_of_typedef)
<< Name << Kind << TND->getUnderlyingType();
m_Sema->Diag(PrevDecl->getLocation(),
diag::note_previous_decl) << PrevDecl;
Invalid = true;
// Otherwise, diagnose.
} else {
// The tag name clashes with something else in the target scope,
// issue an error and recover by making this tag be anonymous.
m_Sema->Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
m_Sema->Diag(PrevDecl->getLocation(), diag::note_previous_definition);
Name = 0;
Invalid = true;
}
// The existing declaration isn't relevant to us; we're in a
// new scope, so clear out the previous declaration.
Previous.clear();
}
}
if (Invalid) {
return false;
}
return true;
}
/// CheckReinterpretCast - Check that a reinterpret_cast\<DestType\>(SrcExpr) is
/// valid.
/// Refer to C++ 5.2.10 for details. reinterpret_cast is typically used in code
/// like this:
/// char *bytes = reinterpret_cast\<char*\>(int_ptr);
void
CheckReinterpretCast(Sema &Self, Expr *&SrcExpr, QualType DestType,
const SourceRange &OpRange, const SourceRange &DestRange)
{
QualType OrigDestType = DestType, OrigSrcType = SrcExpr->getType();
DestType = Self.Context.getCanonicalType(DestType);
QualType SrcType = SrcExpr->getType();
if (const LValueReferenceType *DestTypeTmp =
DestType->getAsLValueReferenceType()) {
if (SrcExpr->isLvalue(Self.Context) != Expr::LV_Valid) {
// Cannot cast non-lvalue to reference type.
Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_rvalue)
<< "reinterpret_cast" << OrigDestType << SrcExpr->getSourceRange();
return;
}
// C++ 5.2.10p10: [...] a reference cast reinterpret_cast<T&>(x) has the
// same effect as the conversion *reinterpret_cast<T*>(&x) with the
// built-in & and * operators.
// This code does this transformation for the checked types.
DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
SrcType = Self.Context.getPointerType(SrcType);
} else if (const RValueReferenceType *DestTypeTmp =
DestType->getAsRValueReferenceType()) {
// Both the reference conversion and the rvalue rules apply.
Self.DefaultFunctionArrayConversion(SrcExpr);
SrcType = SrcExpr->getType();
DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
SrcType = Self.Context.getPointerType(SrcType);
} else {
// C++ 5.2.10p1: [...] the lvalue-to-rvalue, array-to-pointer, and
// function-to-pointer standard conversions are performed on the
// expression v.
Self.DefaultFunctionArrayConversion(SrcExpr);
SrcType = SrcExpr->getType();
}
// Canonicalize source for comparison.
SrcType = Self.Context.getCanonicalType(SrcType);
const MemberPointerType *DestMemPtr = DestType->getAsMemberPointerType(),
*SrcMemPtr = SrcType->getAsMemberPointerType();
if (DestMemPtr && SrcMemPtr) {
// C++ 5.2.10p9: An rvalue of type "pointer to member of X of type T1"
// can be explicitly converted to an rvalue of type "pointer to member
// of Y of type T2" if T1 and T2 are both function types or both object
// types.
if (DestMemPtr->getPointeeType()->isFunctionType() !=
SrcMemPtr->getPointeeType()->isFunctionType()) {
Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_generic)
<< "reinterpret_cast" << OrigDestType << OrigSrcType << OpRange;
return;
}
// C++ 5.2.10p2: The reinterpret_cast operator shall not cast away
// constness.
if (CastsAwayConstness(Self, SrcType, DestType)) {
Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_const_away)
<< "reinterpret_cast" << OrigDestType << OrigSrcType << OpRange;
return;
}
// A valid member pointer cast.
return;
}
// See below for the enumeral issue.
if (SrcType->isNullPtrType() && DestType->isIntegralType() &&
!DestType->isEnumeralType()) {
// C++0x 5.2.10p4: A pointer can be explicitly converted to any integral
// type large enough to hold it. A value of std::nullptr_t can be
// converted to an integral type; the conversion has the same meaning
// and validity as a conversion of (void*)0 to the integral type.
if (Self.Context.getTypeSize(SrcType) >
Self.Context.getTypeSize(DestType)) {
Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_small_int)
<< OrigDestType << DestRange;
}
return;
}
bool destIsPtr = DestType->isPointerType();
bool srcIsPtr = SrcType->isPointerType();
if (!destIsPtr && !srcIsPtr) {
// Except for std::nullptr_t->integer and lvalue->reference, which are
// handled above, at least one of the two arguments must be a pointer.
Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_generic)
<< "reinterpret_cast" << OrigDestType << OrigSrcType << OpRange;
return;
}
if (SrcType == DestType) {
// C++ 5.2.10p2 has a note that mentions that, subject to all other
// restrictions, a cast to the same type is allowed. The intent is not
// entirely clear here, since all other paragraphs explicitly forbid casts
// to the same type. However, the behavior of compilers is pretty consistent
// on this point: allow same-type conversion if the involved types are
// pointers, disallow otherwise.
return;
}
// Note: Clang treats enumeration types as integral types. If this is ever
// changed for C++, the additional check here will be redundant.
if (DestType->isIntegralType() && !DestType->isEnumeralType()) {
assert(srcIsPtr && "One type must be a pointer");
// C++ 5.2.10p4: A pointer can be explicitly converted to any integral
// type large enough to hold it.
if (Self.Context.getTypeSize(SrcType) >
Self.Context.getTypeSize(DestType)) {
Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_small_int)
<< OrigDestType << DestRange;
}
return;
}
if (SrcType->isIntegralType() || SrcType->isEnumeralType()) {
assert(destIsPtr && "One type must be a pointer");
// C++ 5.2.10p5: A value of integral or enumeration type can be explicitly
// converted to a pointer.
return;
}
if (!destIsPtr || !srcIsPtr) {
// With the valid non-pointer conversions out of the way, we can be even
// more stringent.
Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_generic)
<< "reinterpret_cast" << OrigDestType << OrigSrcType << OpRange;
return;
}
// C++ 5.2.10p2: The reinterpret_cast operator shall not cast away constness.
if (CastsAwayConstness(Self, SrcType, DestType)) {
Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_const_away)
<< "reinterpret_cast" << OrigDestType << OrigSrcType << OpRange;
return;
}
// Not casting away constness, so the only remaining check is for compatible
// pointer categories.
if (SrcType->isFunctionPointerType()) {
if (DestType->isFunctionPointerType()) {
// C++ 5.2.10p6: A pointer to a function can be explicitly converted to
// a pointer to a function of a different type.
return;
}
// C++0x 5.2.10p8: Converting a pointer to a function into a pointer to
// an object type or vice versa is conditionally-supported.
// Compilers support it in C++03 too, though, because it's necessary for
// casting the return value of dlsym() and GetProcAddress().
// FIXME: Conditionally-supported behavior should be configurable in the
// TargetInfo or similar.
if (!Self.getLangOptions().CPlusPlus0x) {
Self.Diag(OpRange.getBegin(), diag::ext_reinterpret_cast_fn_obj)
<< OpRange;
}
return;
}
if (DestType->isFunctionPointerType()) {
// See above.
if (!Self.getLangOptions().CPlusPlus0x) {
Self.Diag(OpRange.getBegin(), diag::ext_reinterpret_cast_fn_obj)
<< OpRange;
}
return;
}
// C++ 5.2.10p7: A pointer to an object can be explicitly converted to
// a pointer to an object of different type.
// Void pointers are not specified, but supported by every compiler out there.
// So we finish by allowing everything that remains - it's got to be two
// object pointers.
}
