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//===------ SemaDeclCXX.cpp - Semantic Analysis for C++ Declarations ------===//
//
// 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++ declarations.
//
//===----------------------------------------------------------------------===//
#include "clang/Sema/SemaInternal.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/ASTLambda.h"
#include "clang/AST/ASTMutationListener.h"
#include "clang/AST/CXXInheritance.h"
#include "clang/AST/CharUnits.h"
#include "clang/AST/EvaluatedExprVisitor.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/RecordLayout.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/AST/StmtVisitor.h"
#include "clang/AST/TypeLoc.h"
#include "clang/AST/TypeOrdering.h"
#include "clang/Basic/PartialDiagnostic.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Lex/LiteralSupport.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Sema/CXXFieldCollector.h"
#include "clang/Sema/DeclSpec.h"
#include "clang/Sema/Initialization.h"
#include "clang/Sema/Lookup.h"
#include "clang/Sema/ParsedTemplate.h"
#include "clang/Sema/Scope.h"
#include "clang/Sema/ScopeInfo.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include <map>
#include <set>
using namespace clang;
//===----------------------------------------------------------------------===//
// CheckDefaultArgumentVisitor
//===----------------------------------------------------------------------===//
namespace {
/// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses
/// the default argument of a parameter to determine whether it
/// contains any ill-formed subexpressions. For example, this will
/// diagnose the use of local variables or parameters within the
/// default argument expression.
class CheckDefaultArgumentVisitor
: public StmtVisitor<CheckDefaultArgumentVisitor, bool> {
Expr *DefaultArg;
Sema *S;
public:
CheckDefaultArgumentVisitor(Expr *defarg, Sema *s)
: DefaultArg(defarg), S(s) {}
bool VisitExpr(Expr *Node);
bool VisitDeclRefExpr(DeclRefExpr *DRE);
bool VisitCXXThisExpr(CXXThisExpr *ThisE);
bool VisitLambdaExpr(LambdaExpr *Lambda);
bool VisitPseudoObjectExpr(PseudoObjectExpr *POE);
};
/// VisitExpr - Visit all of the children of this expression.
bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) {
bool IsInvalid = false;
for (Stmt::child_range I = Node->children(); I; ++I)
IsInvalid |= Visit(*I);
return IsInvalid;
}
/// VisitDeclRefExpr - Visit a reference to a declaration, to
/// determine whether this declaration can be used in the default
/// argument expression.
bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) {
NamedDecl *Decl = DRE->getDecl();
if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) {
// C++ [dcl.fct.default]p9
// Default arguments are evaluated each time the function is
// called. The order of evaluation of function arguments is
// unspecified. Consequently, parameters of a function shall not
// be used in default argument expressions, even if they are not
// evaluated. Parameters of a function declared before a default
// argument expression are in scope and can hide namespace and
// class member names.
return S->Diag(DRE->getLocStart(),
diag::err_param_default_argument_references_param)
<< Param->getDeclName() << DefaultArg->getSourceRange();
} else if (VarDecl *VDecl = dyn_cast<VarDecl>(Decl)) {
// C++ [dcl.fct.default]p7
// Local variables shall not be used in default argument
// expressions.
if (VDecl->isLocalVarDecl())
return S->Diag(DRE->getLocStart(),
diag::err_param_default_argument_references_local)
<< VDecl->getDeclName() << DefaultArg->getSourceRange();
}
return false;
}
/// VisitCXXThisExpr - Visit a C++ "this" expression.
bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(CXXThisExpr *ThisE) {
// C++ [dcl.fct.default]p8:
// The keyword this shall not be used in a default argument of a
// member function.
return S->Diag(ThisE->getLocStart(),
diag::err_param_default_argument_references_this)
<< ThisE->getSourceRange();
}
bool CheckDefaultArgumentVisitor::VisitPseudoObjectExpr(PseudoObjectExpr *POE) {
bool Invalid = false;
for (PseudoObjectExpr::semantics_iterator
i = POE->semantics_begin(), e = POE->semantics_end(); i != e; ++i) {
Expr *E = *i;
// Look through bindings.
if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
E = OVE->getSourceExpr();
assert(E && "pseudo-object binding without source expression?");
}
Invalid |= Visit(E);
}
return Invalid;
}
bool CheckDefaultArgumentVisitor::VisitLambdaExpr(LambdaExpr *Lambda) {
// C++11 [expr.lambda.prim]p13:
// A lambda-expression appearing in a default argument shall not
// implicitly or explicitly capture any entity.
if (Lambda->capture_begin() == Lambda->capture_end())
return false;
return S->Diag(Lambda->getLocStart(),
diag::err_lambda_capture_default_arg);
}
}
void
Sema::ImplicitExceptionSpecification::CalledDecl(SourceLocation CallLoc,
const CXXMethodDecl *Method) {
// If we have an MSAny spec already, don't bother.
if (!Method || ComputedEST == EST_MSAny)
return;
const FunctionProtoType *Proto
= Method->getType()->getAs<FunctionProtoType>();
Proto = Self->ResolveExceptionSpec(CallLoc, Proto);
if (!Proto)
return;
ExceptionSpecificationType EST = Proto->getExceptionSpecType();
// If this function can throw any exceptions, make a note of that.
if (EST == EST_MSAny || EST == EST_None) {
ClearExceptions();
ComputedEST = EST;
return;
}
// FIXME: If the call to this decl is using any of its default arguments, we
// need to search them for potentially-throwing calls.
// If this function has a basic noexcept, it doesn't affect the outcome.
if (EST == EST_BasicNoexcept)
return;
// If we have a throw-all spec at this point, ignore the function.
if (ComputedEST == EST_None)
return;
// If we're still at noexcept(true) and there's a nothrow() callee,
// change to that specification.
if (EST == EST_DynamicNone) {
if (ComputedEST == EST_BasicNoexcept)
ComputedEST = EST_DynamicNone;
return;
}
// Check out noexcept specs.
if (EST == EST_ComputedNoexcept) {
FunctionProtoType::NoexceptResult NR =
Proto->getNoexceptSpec(Self->Context);
assert(NR != FunctionProtoType::NR_NoNoexcept &&
"Must have noexcept result for EST_ComputedNoexcept.");
assert(NR != FunctionProtoType::NR_Dependent &&
"Should not generate implicit declarations for dependent cases, "
"and don't know how to handle them anyway.");
// noexcept(false) -> no spec on the new function
if (NR == FunctionProtoType::NR_Throw) {
ClearExceptions();
ComputedEST = EST_None;
}
// noexcept(true) won't change anything either.
return;
}
assert(EST == EST_Dynamic && "EST case not considered earlier.");
assert(ComputedEST != EST_None &&
"Shouldn't collect exceptions when throw-all is guaranteed.");
ComputedEST = EST_Dynamic;
// Record the exceptions in this function's exception specification.
for (const auto &E : Proto->exceptions())
if (ExceptionsSeen.insert(Self->Context.getCanonicalType(E)))
Exceptions.push_back(E);
}
void Sema::ImplicitExceptionSpecification::CalledExpr(Expr *E) {
if (!E || ComputedEST == EST_MSAny)
return;
// FIXME:
//
// C++0x [except.spec]p14:
// [An] implicit exception-specification specifies the type-id T if and
// only if T is allowed by the exception-specification of a function directly
// invoked by f's implicit definition; f shall allow all exceptions if any
// function it directly invokes allows all exceptions, and f shall allow no
// exceptions if every function it directly invokes allows no exceptions.
//
// Note in particular that if an implicit exception-specification is generated
// for a function containing a throw-expression, that specification can still
// be noexcept(true).
//
// Note also that 'directly invoked' is not defined in the standard, and there
// is no indication that we should only consider potentially-evaluated calls.
//
// Ultimately we should implement the intent of the standard: the exception
// specification should be the set of exceptions which can be thrown by the
// implicit definition. For now, we assume that any non-nothrow expression can
// throw any exception.
if (Self->canThrow(E))
ComputedEST = EST_None;
}
bool
Sema::SetParamDefaultArgument(ParmVarDecl *Param, Expr *Arg,
SourceLocation EqualLoc) {
if (RequireCompleteType(Param->getLocation(), Param->getType(),
diag::err_typecheck_decl_incomplete_type)) {
Param->setInvalidDecl();
return true;
}
// C++ [dcl.fct.default]p5
// A default argument expression is implicitly converted (clause
// 4) to the parameter type. The default argument expression has
// the same semantic constraints as the initializer expression in
// a declaration of a variable of the parameter type, using the
// copy-initialization semantics (8.5).
InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
Param);
InitializationKind Kind = InitializationKind::CreateCopy(Param->getLocation(),
EqualLoc);
InitializationSequence InitSeq(*this, Entity, Kind, Arg);
ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Arg);
if (Result.isInvalid())
return true;
Arg = Result.getAs<Expr>();
CheckCompletedExpr(Arg, EqualLoc);
Arg = MaybeCreateExprWithCleanups(Arg);
// Okay: add the default argument to the parameter
Param->setDefaultArg(Arg);
// We have already instantiated this parameter; provide each of the
// instantiations with the uninstantiated default argument.
UnparsedDefaultArgInstantiationsMap::iterator InstPos
= UnparsedDefaultArgInstantiations.find(Param);
if (InstPos != UnparsedDefaultArgInstantiations.end()) {
for (unsigned I = 0, N = InstPos->second.size(); I != N; ++I)
InstPos->second[I]->setUninstantiatedDefaultArg(Arg);
// We're done tracking this parameter's instantiations.
UnparsedDefaultArgInstantiations.erase(InstPos);
}
return false;
}
/// ActOnParamDefaultArgument - Check whether the default argument
/// provided for a function parameter is well-formed. If so, attach it
/// to the parameter declaration.
void
Sema::ActOnParamDefaultArgument(Decl *param, SourceLocation EqualLoc,
Expr *DefaultArg) {
if (!param || !DefaultArg)
return;
ParmVarDecl *Param = cast<ParmVarDecl>(param);
UnparsedDefaultArgLocs.erase(Param);
// Default arguments are only permitted in C++
if (!getLangOpts().CPlusPlus) {
Diag(EqualLoc, diag::err_param_default_argument)
<< DefaultArg->getSourceRange();
Param->setInvalidDecl();
return;
}
// Check for unexpanded parameter packs.
if (DiagnoseUnexpandedParameterPack(DefaultArg, UPPC_DefaultArgument)) {
Param->setInvalidDecl();
return;
}
// Check that the default argument is well-formed
CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg, this);
if (DefaultArgChecker.Visit(DefaultArg)) {
Param->setInvalidDecl();
return;
}
SetParamDefaultArgument(Param, DefaultArg, EqualLoc);
}
/// ActOnParamUnparsedDefaultArgument - We've seen a default
/// argument for a function parameter, but we can't parse it yet
/// because we're inside a class definition. Note that this default
/// argument will be parsed later.
void Sema::ActOnParamUnparsedDefaultArgument(Decl *param,
SourceLocation EqualLoc,
SourceLocation ArgLoc) {
if (!param)
return;
ParmVarDecl *Param = cast<ParmVarDecl>(param);
Param->setUnparsedDefaultArg();
UnparsedDefaultArgLocs[Param] = ArgLoc;
}
/// ActOnParamDefaultArgumentError - Parsing or semantic analysis of
/// the default argument for the parameter param failed.
void Sema::ActOnParamDefaultArgumentError(Decl *param) {
if (!param)
return;
ParmVarDecl *Param = cast<ParmVarDecl>(param);
Param->setInvalidDecl();
UnparsedDefaultArgLocs.erase(Param);
}
/// CheckExtraCXXDefaultArguments - Check for any extra default
/// arguments in the declarator, which is not a function declaration
/// or definition and therefore is not permitted to have default
/// arguments. This routine should be invoked for every declarator
/// that is not a function declaration or definition.
void Sema::CheckExtraCXXDefaultArguments(Declarator &D) {
// C++ [dcl.fct.default]p3
// A default argument expression shall be specified only in the
// parameter-declaration-clause of a function declaration or in a
// template-parameter (14.1). It shall not be specified for a
// parameter pack. If it is specified in a
// parameter-declaration-clause, it shall not occur within a
// declarator or abstract-declarator of a parameter-declaration.
bool MightBeFunction = D.isFunctionDeclarationContext();
for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
DeclaratorChunk &chunk = D.getTypeObject(i);
if (chunk.Kind == DeclaratorChunk::Function) {
if (MightBeFunction) {
// This is a function declaration. It can have default arguments, but
// keep looking in case its return type is a function type with default
// arguments.
MightBeFunction = false;
continue;
}
for (unsigned argIdx = 0, e = chunk.Fun.NumParams; argIdx != e;
++argIdx) {
ParmVarDecl *Param = cast<ParmVarDecl>(chunk.Fun.Params[argIdx].Param);
if (Param->hasUnparsedDefaultArg()) {
CachedTokens *Toks = chunk.Fun.Params[argIdx].DefaultArgTokens;
Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
<< SourceRange((*Toks)[1].getLocation(),
Toks->back().getLocation());
delete Toks;
chunk.Fun.Params[argIdx].DefaultArgTokens = nullptr;
} else if (Param->getDefaultArg()) {
Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
<< Param->getDefaultArg()->getSourceRange();
Param->setDefaultArg(nullptr);
}
}
} else if (chunk.Kind != DeclaratorChunk::Paren) {
MightBeFunction = false;
}
}
}
static bool functionDeclHasDefaultArgument(const FunctionDecl *FD) {
for (unsigned NumParams = FD->getNumParams(); NumParams > 0; --NumParams) {
const ParmVarDecl *PVD = FD->getParamDecl(NumParams-1);
if (!PVD->hasDefaultArg())
return false;
if (!PVD->hasInheritedDefaultArg())
return true;
}
return false;
}
/// MergeCXXFunctionDecl - Merge two declarations of the same C++
/// function, once we already know that they have the same
/// type. Subroutine of MergeFunctionDecl. Returns true if there was an
/// error, false otherwise.
bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old,
Scope *S) {
bool Invalid = false;
// C++ [dcl.fct.default]p4:
// For non-template functions, default arguments can be added in
// later declarations of a function in the same
// scope. Declarations in different scopes have completely
// distinct sets of default arguments. That is, declarations in
// inner scopes do not acquire default arguments from
// declarations in outer scopes, and vice versa. In a given
// function declaration, all parameters subsequent to a
// parameter with a default argument shall have default
// arguments supplied in this or previous declarations. A
// default argument shall not be redefined by a later
// declaration (not even to the same value).
//
// C++ [dcl.fct.default]p6:
// Except for member functions of class templates, the default arguments
// in a member function definition that appears outside of the class
// definition are added to the set of default arguments provided by the
// member function declaration in the class definition.
for (unsigned p = 0, NumParams = Old->getNumParams(); p < NumParams; ++p) {
ParmVarDecl *OldParam = Old->getParamDecl(p);
ParmVarDecl *NewParam = New->getParamDecl(p);
bool OldParamHasDfl = OldParam->hasDefaultArg();
bool NewParamHasDfl = NewParam->hasDefaultArg();
NamedDecl *ND = Old;
// The declaration context corresponding to the scope is the semantic
// parent, unless this is a local function declaration, in which case
// it is that surrounding function.
DeclContext *ScopeDC = New->getLexicalDeclContext();
if (!ScopeDC->isFunctionOrMethod())
ScopeDC = New->getDeclContext();
if (S && !isDeclInScope(ND, ScopeDC, S) &&
!New->getDeclContext()->isRecord())
// Ignore default parameters of old decl if they are not in
// the same scope and this is not an out-of-line definition of
// a member function.
OldParamHasDfl = false;
if (OldParamHasDfl && NewParamHasDfl) {
unsigned DiagDefaultParamID =
diag::err_param_default_argument_redefinition;
// MSVC accepts that default parameters be redefined for member functions
// of template class. The new default parameter's value is ignored.
Invalid = true;
if (getLangOpts().MicrosoftExt) {
CXXMethodDecl* MD = dyn_cast<CXXMethodDecl>(New);
if (MD && MD->getParent()->getDescribedClassTemplate()) {
// Merge the old default argument into the new parameter.
NewParam->setHasInheritedDefaultArg();
if (OldParam->hasUninstantiatedDefaultArg())
NewParam->setUninstantiatedDefaultArg(
OldParam->getUninstantiatedDefaultArg());
else
NewParam->setDefaultArg(OldParam->getInit());
DiagDefaultParamID = diag::warn_param_default_argument_redefinition;
Invalid = false;
}
}
// FIXME: If we knew where the '=' was, we could easily provide a fix-it
// hint here. Alternatively, we could walk the type-source information
// for NewParam to find the last source location in the type... but it
// isn't worth the effort right now. This is the kind of test case that
// is hard to get right:
// int f(int);
// void g(int (*fp)(int) = f);
// void g(int (*fp)(int) = &f);
Diag(NewParam->getLocation(), DiagDefaultParamID)
<< NewParam->getDefaultArgRange();
// Look for the function declaration where the default argument was
// actually written, which may be a declaration prior to Old.
for (FunctionDecl *Older = Old->getPreviousDecl();
Older; Older = Older->getPreviousDecl()) {
if (!Older->getParamDecl(p)->hasDefaultArg())
break;
OldParam = Older->getParamDecl(p);
}
Diag(OldParam->getLocation(), diag::note_previous_definition)
<< OldParam->getDefaultArgRange();
} else if (OldParamHasDfl) {
// Merge the old default argument into the new parameter.
// It's important to use getInit() here; getDefaultArg()
// strips off any top-level ExprWithCleanups.
NewParam->setHasInheritedDefaultArg();
if (OldParam->hasUninstantiatedDefaultArg())
NewParam->setUninstantiatedDefaultArg(
OldParam->getUninstantiatedDefaultArg());
else
NewParam->setDefaultArg(OldParam->getInit());
} else if (NewParamHasDfl) {
if (New->getDescribedFunctionTemplate()) {
// Paragraph 4, quoted above, only applies to non-template functions.
Diag(NewParam->getLocation(),
diag::err_param_default_argument_template_redecl)
<< NewParam->getDefaultArgRange();
Diag(Old->getLocation(), diag::note_template_prev_declaration)
<< false;
} else if (New->getTemplateSpecializationKind()
!= TSK_ImplicitInstantiation &&
New->getTemplateSpecializationKind() != TSK_Undeclared) {
// C++ [temp.expr.spec]p21:
// Default function arguments shall not be specified in a declaration
// or a definition for one of the following explicit specializations:
// - the explicit specialization of a function template;
// - the explicit specialization of a member function template;
// - the explicit specialization of a member function of a class
// template where the class template specialization to which the
// member function specialization belongs is implicitly
// instantiated.
Diag(NewParam->getLocation(), diag::err_template_spec_default_arg)
<< (New->getTemplateSpecializationKind() ==TSK_ExplicitSpecialization)
<< New->getDeclName()
<< NewParam->getDefaultArgRange();
} else if (New->getDeclContext()->isDependentContext()) {
// C++ [dcl.fct.default]p6 (DR217):
// Default arguments for a member function of a class template shall
// be specified on the initial declaration of the member function
// within the class template.
//
// Reading the tea leaves a bit in DR217 and its reference to DR205
// leads me to the conclusion that one cannot add default function
// arguments for an out-of-line definition of a member function of a
// dependent type.
int WhichKind = 2;
if (CXXRecordDecl *Record
= dyn_cast<CXXRecordDecl>(New->getDeclContext())) {
if (Record->getDescribedClassTemplate())
WhichKind = 0;
else if (isa<ClassTemplatePartialSpecializationDecl>(Record))
WhichKind = 1;
else
WhichKind = 2;
}
Diag(NewParam->getLocation(),
diag::err_param_default_argument_member_template_redecl)
<< WhichKind
<< NewParam->getDefaultArgRange();
}
}
}
// DR1344: If a default argument is added outside a class definition and that
// default argument makes the function a special member function, the program
// is ill-formed. This can only happen for constructors.
if (isa<CXXConstructorDecl>(New) &&
New->getMinRequiredArguments() < Old->getMinRequiredArguments()) {
CXXSpecialMember NewSM = getSpecialMember(cast<CXXMethodDecl>(New)),
OldSM = getSpecialMember(cast<CXXMethodDecl>(Old));
if (NewSM != OldSM) {
ParmVarDecl *NewParam = New->getParamDecl(New->getMinRequiredArguments());
assert(NewParam->hasDefaultArg());
Diag(NewParam->getLocation(), diag::err_default_arg_makes_ctor_special)
<< NewParam->getDefaultArgRange() << NewSM;
Diag(Old->getLocation(), diag::note_previous_declaration);
}
}
const FunctionDecl *Def;
// C++11 [dcl.constexpr]p1: If any declaration of a function or function
// template has a constexpr specifier then all its declarations shall
// contain the constexpr specifier.
if (New->isConstexpr() != Old->isConstexpr()) {
Diag(New->getLocation(), diag::err_constexpr_redecl_mismatch)
<< New << New->isConstexpr();
Diag(Old->getLocation(), diag::note_previous_declaration);
Invalid = true;
} else if (!Old->isInlined() && New->isInlined() && Old->isDefined(Def)) {
// C++11 [dcl.fcn.spec]p4:
// If the definition of a function appears in a translation unit before its
// first declaration as inline, the program is ill-formed.
Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
Diag(Def->getLocation(), diag::note_previous_definition);
Invalid = true;
}
// C++11 [dcl.fct.default]p4: If a friend declaration specifies a default
// argument expression, that declaration shall be a definition and shall be
// the only declaration of the function or function template in the
// translation unit.
if (Old->getFriendObjectKind() == Decl::FOK_Undeclared &&
functionDeclHasDefaultArgument(Old)) {
Diag(New->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
Diag(Old->getLocation(), diag::note_previous_declaration);
Invalid = true;
}
if (CheckEquivalentExceptionSpec(Old, New))
Invalid = true;
return Invalid;
}
/// \brief Merge the exception specifications of two variable declarations.
///
/// This is called when there's a redeclaration of a VarDecl. The function
/// checks if the redeclaration might have an exception specification and
/// validates compatibility and merges the specs if necessary.
void Sema::MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old) {
// Shortcut if exceptions are disabled.
if (!getLangOpts().CXXExceptions)
return;
assert(Context.hasSameType(New->getType(), Old->getType()) &&
"Should only be called if types are otherwise the same.");
QualType NewType = New->getType();
QualType OldType = Old->getType();
// We're only interested in pointers and references to functions, as well
// as pointers to member functions.
if (const ReferenceType *R = NewType->getAs<ReferenceType>()) {
NewType = R->getPointeeType();
OldType = OldType->getAs<ReferenceType>()->getPointeeType();
} else if (const PointerType *P = NewType->getAs<PointerType>()) {
NewType = P->getPointeeType();
OldType = OldType->getAs<PointerType>()->getPointeeType();
} else if (const MemberPointerType *M = NewType->getAs<MemberPointerType>()) {
NewType = M->getPointeeType();
OldType = OldType->getAs<MemberPointerType>()->getPointeeType();
}
if (!NewType->isFunctionProtoType())
return;
// There's lots of special cases for functions. For function pointers, system
// libraries are hopefully not as broken so that we don't need these
// workarounds.
if (CheckEquivalentExceptionSpec(
OldType->getAs<FunctionProtoType>(), Old->getLocation(),
NewType->getAs<FunctionProtoType>(), New->getLocation())) {
New->setInvalidDecl();
}
}
/// CheckCXXDefaultArguments - Verify that the default arguments for a
/// function declaration are well-formed according to C++
/// [dcl.fct.default].
void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) {
unsigned NumParams = FD->getNumParams();
unsigned p;
// Find first parameter with a default argument
for (p = 0; p < NumParams; ++p) {
ParmVarDecl *Param = FD->getParamDecl(p);
if (Param->hasDefaultArg())
break;
}
// C++ [dcl.fct.default]p4:
// In a given function declaration, all parameters
// subsequent to a parameter with a default argument shall
// have default arguments supplied in this or previous
// declarations. A default argument shall not be redefined
// by a later declaration (not even to the same value).
unsigned LastMissingDefaultArg = 0;
for (; p < NumParams; ++p) {
ParmVarDecl *Param = FD->getParamDecl(p);
if (!Param->hasDefaultArg()) {
if (Param->isInvalidDecl())
/* We already complained about this parameter. */;
else if (Param->getIdentifier())
Diag(Param->getLocation(),
diag::err_param_default_argument_missing_name)
<< Param->getIdentifier();
else
Diag(Param->getLocation(),
diag::err_param_default_argument_missing);
LastMissingDefaultArg = p;
}
}
if (LastMissingDefaultArg > 0) {
// Some default arguments were missing. Clear out all of the
// default arguments up to (and including) the last missing
// default argument, so that we leave the function parameters
// in a semantically valid state.
for (p = 0; p <= LastMissingDefaultArg; ++p) {
ParmVarDecl *Param = FD->getParamDecl(p);
if (Param->hasDefaultArg()) {
Param->setDefaultArg(nullptr);
}
}
}
}
// CheckConstexprParameterTypes - Check whether a function's parameter types
// are all literal types. If so, return true. If not, produce a suitable
// diagnostic and return false.
static bool CheckConstexprParameterTypes(Sema &SemaRef,
const FunctionDecl *FD) {
unsigned ArgIndex = 0;
const FunctionProtoType *FT = FD->getType()->getAs<FunctionProtoType>();
for (FunctionProtoType::param_type_iterator i = FT->param_type_begin(),
e = FT->param_type_end();
i != e; ++i, ++ArgIndex) {
const ParmVarDecl *PD = FD->getParamDecl(ArgIndex);
SourceLocation ParamLoc = PD->getLocation();
if (!(*i)->isDependentType() &&
SemaRef.RequireLiteralType(ParamLoc, *i,
diag::err_constexpr_non_literal_param,
ArgIndex+1, PD->getSourceRange(),
isa<CXXConstructorDecl>(FD)))
return false;
}
return true;
}
/// \brief Get diagnostic %select index for tag kind for
/// record diagnostic message.
/// WARNING: Indexes apply to particular diagnostics only!
///
/// \returns diagnostic %select index.
static unsigned getRecordDiagFromTagKind(TagTypeKind Tag) {
switch (Tag) {
case TTK_Struct: return 0;
case TTK_Interface: return 1;
case TTK_Class: return 2;
default: llvm_unreachable("Invalid tag kind for record diagnostic!");
}
}
// CheckConstexprFunctionDecl - Check whether a function declaration satisfies
// the requirements of a constexpr function definition or a constexpr
// constructor definition. If so, return true. If not, produce appropriate
// diagnostics and return false.
//
// This implements C++11 [dcl.constexpr]p3,4, as amended by DR1360.
bool Sema::CheckConstexprFunctionDecl(const FunctionDecl *NewFD) {
const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
if (MD && MD->isInstance()) {
// C++11 [dcl.constexpr]p4:
// The definition of a constexpr constructor shall satisfy the following
// constraints:
// - the class shall not have any virtual base classes;
const CXXRecordDecl *RD = MD->getParent();
if (RD->getNumVBases()) {
Diag(NewFD->getLocation(), diag::err_constexpr_virtual_base)
<< isa<CXXConstructorDecl>(NewFD)
<< getRecordDiagFromTagKind(RD->getTagKind()) << RD->getNumVBases();
for (const auto &I : RD->vbases())
Diag(I.getLocStart(),
diag::note_constexpr_virtual_base_here) << I.getSourceRange();
return false;
}
}
if (!isa<CXXConstructorDecl>(NewFD)) {
// C++11 [dcl.constexpr]p3:
// The definition of a constexpr function shall satisfy the following
// constraints:
// - it shall not be virtual;
const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD);
if (Method && Method->isVirtual()) {
Diag(NewFD->getLocation(), diag::err_constexpr_virtual);
// If it's not obvious why this function is virtual, find an overridden
// function which uses the 'virtual' keyword.
const CXXMethodDecl *WrittenVirtual = Method;
while (!WrittenVirtual->isVirtualAsWritten())
WrittenVirtual = *WrittenVirtual->begin_overridden_methods();
if (WrittenVirtual != Method)
Diag(WrittenVirtual->getLocation(),
diag::note_overridden_virtual_function);
return false;
}
// - its return type shall be a literal type;
QualType RT = NewFD->getReturnType();
if (!RT->isDependentType() &&
RequireLiteralType(NewFD->getLocation(), RT,
diag::err_constexpr_non_literal_return))
return false;
}
// - each of its parameter types shall be a literal type;
if (!CheckConstexprParameterTypes(*this, NewFD))
return false;
return true;
}
/// Check the given declaration statement is legal within a constexpr function
/// body. C++11 [dcl.constexpr]p3,p4, and C++1y [dcl.constexpr]p3.
///
/// \return true if the body is OK (maybe only as an extension), false if we
/// have diagnosed a problem.
static bool CheckConstexprDeclStmt(Sema &SemaRef, const FunctionDecl *Dcl,
DeclStmt *DS, SourceLocation &Cxx1yLoc) {
// C++11 [dcl.constexpr]p3 and p4:
// The definition of a constexpr function(p3) or constructor(p4) [...] shall
// contain only
for (const auto *DclIt : DS->decls()) {
switch (DclIt->getKind()) {
case Decl::StaticAssert:
case Decl::Using:
case Decl::UsingShadow:
case Decl::UsingDirective:
case Decl::UnresolvedUsingTypename:
case Decl::UnresolvedUsingValue:
// - static_assert-declarations
// - using-declarations,
// - using-directives,
continue;
case Decl::Typedef:
case Decl::TypeAlias: {
// - typedef declarations and alias-declarations that do not define
// classes or enumerations,
const auto *TN = cast<TypedefNameDecl>(DclIt);
if (TN->getUnderlyingType()->isVariablyModifiedType()) {
// Don't allow variably-modified types in constexpr functions.
TypeLoc TL = TN->getTypeSourceInfo()->getTypeLoc();
SemaRef.Diag(TL.getBeginLoc(), diag::err_constexpr_vla)
<< TL.getSourceRange() << TL.getType()
<< isa<CXXConstructorDecl>(Dcl);
return false;
}
continue;
}
case Decl::Enum:
case Decl::CXXRecord:
// C++1y allows types to be defined, not just declared.
if (cast<TagDecl>(DclIt)->isThisDeclarationADefinition())
SemaRef.Diag(DS->getLocStart(),
SemaRef.getLangOpts().CPlusPlus1y
? diag::warn_cxx11_compat_constexpr_type_definition
: diag::ext_constexpr_type_definition)
<< isa<CXXConstructorDecl>(Dcl);
continue;
case Decl::EnumConstant:
case Decl::IndirectField:
case Decl::ParmVar:
// These can only appear with other declarations which are banned in
// C++11 and permitted in C++1y, so ignore them.
continue;
case Decl::Var: {
// C++1y [dcl.constexpr]p3 allows anything except:
// a definition of a variable of non-literal type or of static or
// thread storage duration or for which no initialization is performed.
const auto *VD = cast<VarDecl>(DclIt);
if (VD->isThisDeclarationADefinition()) {
if (VD->isStaticLocal()) {
SemaRef.Diag(VD->getLocation(),
diag::err_constexpr_local_var_static)
<< isa<CXXConstructorDecl>(Dcl)
<< (VD->getTLSKind() == VarDecl::TLS_Dynamic);
return false;
}
if (!VD->getType()->isDependentType() &&
SemaRef.RequireLiteralType(
VD->getLocation(), VD->getType(),
diag::err_constexpr_local_var_non_literal_type,
isa<CXXConstructorDecl>(Dcl)))
return false;
if (!VD->getType()->isDependentType() &&
!VD->hasInit() && !VD->isCXXForRangeDecl()) {
SemaRef.Diag(VD->getLocation(),
diag::err_constexpr_local_var_no_init)
<< isa<CXXConstructorDecl>(Dcl);
return false;
}
}
SemaRef.Diag(VD->getLocation(),
SemaRef.getLangOpts().CPlusPlus1y
? diag::warn_cxx11_compat_constexpr_local_var
: diag::ext_constexpr_local_var)
<< isa<CXXConstructorDecl>(Dcl);
continue;
}
case Decl::NamespaceAlias:
case Decl::Function:
// These are disallowed in C++11 and permitted in C++1y. Allow them
// everywhere as an extension.
if (!Cxx1yLoc.isValid())
Cxx1yLoc = DS->getLocStart();
continue;
default:
SemaRef.Diag(DS->getLocStart(), diag::err_constexpr_body_invalid_stmt)
<< isa<CXXConstructorDecl>(Dcl);
return false;
}
}
return true;
}
/// Check that the given field is initialized within a constexpr constructor.
///
/// \param Dcl The constexpr constructor being checked.
/// \param Field The field being checked. This may be a member of an anonymous
/// struct or union nested within the class being checked.
/// \param Inits All declarations, including anonymous struct/union members and
/// indirect members, for which any initialization was provided.
/// \param Diagnosed Set to true if an error is produced.
static void CheckConstexprCtorInitializer(Sema &SemaRef,
const FunctionDecl *Dcl,
FieldDecl *Field,
llvm::SmallSet<Decl*, 16> &Inits,
bool &Diagnosed) {
if (Field->isInvalidDecl())
return;
if (Field->isUnnamedBitfield())
return;
// Anonymous unions with no variant members and empty anonymous structs do not
// need to be explicitly initialized. FIXME: Anonymous structs that contain no
// indirect fields don't need initializing.
if (Field->isAnonymousStructOrUnion() &&
(Field->getType()->isUnionType()
? !Field->getType()->getAsCXXRecordDecl()->hasVariantMembers()
: Field->getType()->getAsCXXRecordDecl()->isEmpty()))
return;
if (!Inits.count(Field)) {
if (!Diagnosed) {
SemaRef.Diag(Dcl->getLocation(), diag::err_constexpr_ctor_missing_init);
Diagnosed = true;
}
SemaRef.Diag(Field->getLocation(), diag::note_constexpr_ctor_missing_init);
} else if (Field->isAnonymousStructOrUnion()) {
const RecordDecl *RD = Field->getType()->castAs<RecordType>()->getDecl();
for (auto *I : RD->fields())
// If an anonymous union contains an anonymous struct of which any member
// is initialized, all members must be initialized.
if (!RD->isUnion() || Inits.count(I))
CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed);
}
}
/// Check the provided statement is allowed in a constexpr function
/// definition.
static bool
CheckConstexprFunctionStmt(Sema &SemaRef, const FunctionDecl *Dcl, Stmt *S,
SmallVectorImpl<SourceLocation> &ReturnStmts,
SourceLocation &Cxx1yLoc) {
// - its function-body shall be [...] a compound-statement that contains only
switch (S->getStmtClass()) {
case Stmt::NullStmtClass:
// - null statements,
return true;
case Stmt::DeclStmtClass:
// - static_assert-declarations
// - using-declarations,
// - using-directives,
// - typedef declarations and alias-declarations that do not define
// classes or enumerations,
if (!CheckConstexprDeclStmt(SemaRef, Dcl, cast<DeclStmt>(S), Cxx1yLoc))
return false;
return true;
case Stmt::ReturnStmtClass:
// - and exactly one return statement;
if (isa<CXXConstructorDecl>(Dcl)) {
// C++1y allows return statements in constexpr constructors.
if (!Cxx1yLoc.isValid())
Cxx1yLoc = S->getLocStart();
return true;
}
ReturnStmts.push_back(S->getLocStart());
return true;
case Stmt::CompoundStmtClass: {
// C++1y allows compound-statements.
if (!Cxx1yLoc.isValid())
Cxx1yLoc = S->getLocStart();
CompoundStmt *CompStmt = cast<CompoundStmt>(S);
for (auto *BodyIt : CompStmt->body()) {
if (!CheckConstexprFunctionStmt(SemaRef, Dcl, BodyIt, ReturnStmts,
Cxx1yLoc))
return false;
}
return true;
}
case Stmt::AttributedStmtClass:
if (!Cxx1yLoc.isValid())
Cxx1yLoc = S->getLocStart();
return true;
case Stmt::IfStmtClass: {
// C++1y allows if-statements.
if (!Cxx1yLoc.isValid())
Cxx1yLoc = S->getLocStart();
IfStmt *If = cast<IfStmt>(S);
if (!CheckConstexprFunctionStmt(SemaRef, Dcl, If->getThen(), ReturnStmts,
Cxx1yLoc))
return false;
if (If->getElse() &&
!CheckConstexprFunctionStmt(SemaRef, Dcl, If->getElse(), ReturnStmts,
Cxx1yLoc))
return false;
return true;
}
case Stmt::WhileStmtClass:
case Stmt::DoStmtClass:
case Stmt::ForStmtClass:
case Stmt::CXXForRangeStmtClass:
case Stmt::ContinueStmtClass:
// C++1y allows all of these. We don't allow them as extensions in C++11,
// because they don't make sense without variable mutation.
if (!SemaRef.getLangOpts().CPlusPlus1y)
break;
if (!Cxx1yLoc.isValid())
Cxx1yLoc = S->getLocStart();
for (Stmt::child_range Children = S->children(); Children; ++Children)
if (*Children &&
!CheckConstexprFunctionStmt(SemaRef, Dcl, *Children, ReturnStmts,
Cxx1yLoc))
return false;
return true;
case Stmt::SwitchStmtClass:
case Stmt::CaseStmtClass:
case Stmt::DefaultStmtClass:
case Stmt::BreakStmtClass:
// C++1y allows switch-statements, and since they don't need variable
// mutation, we can reasonably allow them in C++11 as an extension.
if (!Cxx1yLoc.isValid())
Cxx1yLoc = S->getLocStart();
for (Stmt::child_range Children = S->children(); Children; ++Children)
if (*Children &&
!CheckConstexprFunctionStmt(SemaRef, Dcl, *Children, ReturnStmts,
Cxx1yLoc))
return false;
return true;
default:
if (!isa<Expr>(S))
break;
// C++1y allows expression-statements.
if (!Cxx1yLoc.isValid())
Cxx1yLoc = S->getLocStart();
return true;
}
SemaRef.Diag(S->getLocStart(), diag::err_constexpr_body_invalid_stmt)
<< isa<CXXConstructorDecl>(Dcl);
return false;
}
/// Check the body for the given constexpr function declaration only contains
/// the permitted types of statement. C++11 [dcl.constexpr]p3,p4.
///
/// \return true if the body is OK, false if we have diagnosed a problem.
bool Sema::CheckConstexprFunctionBody(const FunctionDecl *Dcl, Stmt *Body) {
if (isa<CXXTryStmt>(Body)) {
// C++11 [dcl.constexpr]p3:
// The definition of a constexpr function shall satisfy the following
// constraints: [...]
// - its function-body shall be = delete, = default, or a
// compound-statement
//
// C++11 [dcl.constexpr]p4:
// In the definition of a constexpr constructor, [...]
// - its function-body shall not be a function-try-block;
Diag(Body->getLocStart(), diag::err_constexpr_function_try_block)
<< isa<CXXConstructorDecl>(Dcl);
return false;
}
SmallVector<SourceLocation, 4> ReturnStmts;
// - its function-body shall be [...] a compound-statement that contains only
// [... list of cases ...]
CompoundStmt *CompBody = cast<CompoundStmt>(Body);
SourceLocation Cxx1yLoc;
for (auto *BodyIt : CompBody->body()) {
if (!CheckConstexprFunctionStmt(*this, Dcl, BodyIt, ReturnStmts, Cxx1yLoc))
return false;
}
if (Cxx1yLoc.isValid())
Diag(Cxx1yLoc,
getLangOpts().CPlusPlus1y
? diag::warn_cxx11_compat_constexpr_body_invalid_stmt
: diag::ext_constexpr_body_invalid_stmt)
<< isa<CXXConstructorDecl>(Dcl);
if (const CXXConstructorDecl *Constructor
= dyn_cast<CXXConstructorDecl>(Dcl)) {
const CXXRecordDecl *RD = Constructor->getParent();
// DR1359:
// - every non-variant non-static data member and base class sub-object
// shall be initialized;
// DR1460:
// - if the class is a union having variant members, exactly one of them
// shall be initialized;
if (RD->isUnion()) {
if (Constructor->getNumCtorInitializers() == 0 &&
RD->hasVariantMembers()) {
Diag(Dcl->getLocation(), diag::err_constexpr_union_ctor_no_init);
return false;
}
} else if (!Constructor->isDependentContext() &&
!Constructor->isDelegatingConstructor()) {
assert(RD->getNumVBases() == 0 && "constexpr ctor with virtual bases");
// Skip detailed checking if we have enough initializers, and we would
// allow at most one initializer per member.
bool AnyAnonStructUnionMembers = false;
unsigned Fields = 0;
for (CXXRecordDecl::field_iterator I = RD->field_begin(),
E = RD->field_end(); I != E; ++I, ++Fields) {
if (I->isAnonymousStructOrUnion()) {
AnyAnonStructUnionMembers = true;
break;
}
}
// DR1460:
// - if the class is a union-like class, but is not a union, for each of
// its anonymous union members having variant members, exactly one of
// them shall be initialized;
if (AnyAnonStructUnionMembers ||
Constructor->getNumCtorInitializers() != RD->getNumBases() + Fields) {
// Check initialization of non-static data members. Base classes are
// always initialized so do not need to be checked. Dependent bases
// might not have initializers in the member initializer list.
llvm::SmallSet<Decl*, 16> Inits;
for (const auto *I: Constructor->inits()) {
if (FieldDecl *FD = I->getMember())
Inits.insert(FD);
else if (IndirectFieldDecl *ID = I->getIndirectMember())
Inits.insert(ID->chain_begin(), ID->chain_end());
}
bool Diagnosed = false;
for (auto *I : RD->fields())
CheckConstexprCtorInitializer(*this, Dcl, I, Inits, Diagnosed);
if (Diagnosed)
return false;
}
}
} else {
if (ReturnStmts.empty()) {
// C++1y doesn't require constexpr functions to contain a 'return'
// statement. We still do, unless the return type might be void, because
// otherwise if there's no return statement, the function cannot
// be used in a core constant expression.
bool OK = getLangOpts().CPlusPlus1y &&
(Dcl->getReturnType()->isVoidType() ||
Dcl->getReturnType()->isDependentType());
Diag(Dcl->getLocation(),
OK ? diag::warn_cxx11_compat_constexpr_body_no_return
: diag::err_constexpr_body_no_return);
return OK;
}
if (ReturnStmts.size() > 1) {
Diag(ReturnStmts.back(),
getLangOpts().CPlusPlus1y
? diag::warn_cxx11_compat_constexpr_body_multiple_return
: diag::ext_constexpr_body_multiple_return);
for (unsigned I = 0; I < ReturnStmts.size() - 1; ++I)
Diag(ReturnStmts[I], diag::note_constexpr_body_previous_return);
}
}
// C++11 [dcl.constexpr]p5:
// if no function argument values exist such that the function invocation
// substitution would produce a constant expression, the program is
// ill-formed; no diagnostic required.
// C++11 [dcl.constexpr]p3:
// - every constructor call and implicit conversion used in initializing the
// return value shall be one of those allowed in a constant expression.
// C++11 [dcl.constexpr]p4:
// - every constructor involved in initializing non-static data members and
// base class sub-objects shall be a constexpr constructor.
SmallVector<PartialDiagnosticAt, 8> Diags;
if (!Expr::isPotentialConstantExpr(Dcl, Diags)) {
Diag(Dcl->getLocation(), diag::ext_constexpr_function_never_constant_expr)
<< isa<CXXConstructorDecl>(Dcl);
for (size_t I = 0, N = Diags.size(); I != N; ++I)
Diag(Diags[I].first, Diags[I].second);
// Don't return false here: we allow this for compatibility in
// system headers.
}
return true;
}
/// isCurrentClassName - Determine whether the identifier II is the
/// name of the class type currently being defined. In the case of
/// nested classes, this will only return true if II is the name of
/// the innermost class.
bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *,
const CXXScopeSpec *SS) {
assert(getLangOpts().CPlusPlus && "No class names in C!");
CXXRecordDecl *CurDecl;
if (SS && SS->isSet() && !SS->isInvalid()) {
DeclContext *DC = computeDeclContext(*SS, true);
CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
} else
CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
if (CurDecl && CurDecl->getIdentifier())
return &II == CurDecl->getIdentifier();
return false;
}
/// \brief Determine whether the identifier II is a typo for the name of
/// the class type currently being defined. If so, update it to the identifier
/// that should have been used.
bool Sema::isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS) {
assert(getLangOpts().CPlusPlus && "No class names in C!");
if (!getLangOpts().SpellChecking)
return false;
CXXRecordDecl *CurDecl;
if (SS && SS->isSet() && !SS->isInvalid()) {
DeclContext *DC = computeDeclContext(*SS, true);
CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
} else
CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
if (CurDecl && CurDecl->getIdentifier() && II != CurDecl->getIdentifier() &&
3 * II->getName().edit_distance(CurDecl->getIdentifier()->getName())
< II->getLength()) {
II = CurDecl->getIdentifier();
return true;
}
return false;
}
/// \brief Determine whether the given class is a base class of the given
/// class, including looking at dependent bases.
static bool findCircularInheritance(const CXXRecordDecl *Class,
const CXXRecordDecl *Current) {
SmallVector<const CXXRecordDecl*, 8> Queue;
Class = Class->getCanonicalDecl();
while (true) {
for (const auto &I : Current->bases()) {
CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
if (!Base)
continue;
Base = Base->getDefinition();
if (!Base)
continue;
if (Base->getCanonicalDecl() == Class)
return true;
Queue.push_back(Base);
}
if (Queue.empty())
return false;
Current = Queue.pop_back_val();
}
return false;
}
/// \brief Perform propagation of DLL attributes from a derived class to a
/// templated base class for MS compatibility.
static void propagateDLLAttrToBaseClassTemplate(
Sema &S, CXXRecordDecl *Class, Attr *ClassAttr,
ClassTemplateSpecializationDecl *BaseTemplateSpec, SourceLocation BaseLoc) {
if (getDLLAttr(
BaseTemplateSpec->getSpecializedTemplate()->getTemplatedDecl())) {
// If the base class template has a DLL attribute, don't try to change it.
return;
}
if (BaseTemplateSpec->getSpecializationKind() == TSK_Undeclared) {
// If the base class is not already specialized, we can do the propagation.
auto *NewAttr = cast<InheritableAttr>(ClassAttr->clone(S.getASTContext()));
NewAttr->setInherited(true);
BaseTemplateSpec->addAttr(NewAttr);
return;
}
bool DifferentAttribute = false;
if (Attr *SpecializationAttr = getDLLAttr(BaseTemplateSpec)) {
if (!SpecializationAttr->isInherited()) {
// The template has previously been specialized or instantiated with an
// explicit attribute. We should not try to change it.
return;
}
if (SpecializationAttr->getKind() == ClassAttr->getKind()) {
// The specialization already has the right attribute.
return;
}
DifferentAttribute = true;
}
// The template was previously instantiated or explicitly specialized without
// a dll attribute, or the template was previously instantiated with a
// different inherited attribute. It's too late for us to change the
// attribute, so warn that this is unsupported.
S.Diag(BaseLoc, diag::warn_attribute_dll_instantiated_base_class)
<< BaseTemplateSpec->isExplicitSpecialization() << DifferentAttribute;
S.Diag(ClassAttr->getLocation(), diag::note_attribute);
if (BaseTemplateSpec->isExplicitSpecialization()) {
S.Diag(BaseTemplateSpec->getLocation(),
diag::note_template_class_explicit_specialization_was_here)
<< BaseTemplateSpec;
} else {
S.Diag(BaseTemplateSpec->getPointOfInstantiation(),
diag::note_template_class_instantiation_was_here)
<< BaseTemplateSpec;
}
}
/// \brief Check the validity of a C++ base class specifier.
///
/// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics
/// and returns NULL otherwise.
CXXBaseSpecifier *
Sema::CheckBaseSpecifier(CXXRecordDecl *Class,
SourceRange SpecifierRange,
bool Virtual, AccessSpecifier Access,
TypeSourceInfo *TInfo,
SourceLocation EllipsisLoc) {
QualType BaseType = TInfo->getType();
// C++ [class.union]p1:
// A union shall not have base classes.
if (Class->isUnion()) {
Diag(Class->getLocation(), diag::err_base_clause_on_union)
<< SpecifierRange;
return nullptr;
}
if (EllipsisLoc.isValid() &&
!TInfo->getType()->containsUnexpandedParameterPack()) {
Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
<< TInfo->getTypeLoc().getSourceRange();
EllipsisLoc = SourceLocation();
}
SourceLocation BaseLoc = TInfo->getTypeLoc().getBeginLoc();
if (BaseType->isDependentType()) {
// Make sure that we don't have circular inheritance among our dependent
// bases. For non-dependent bases, the check for completeness below handles
// this.
if (CXXRecordDecl *BaseDecl = BaseType->getAsCXXRecordDecl()) {
if (BaseDecl->getCanonicalDecl() == Class->getCanonicalDecl() ||
((BaseDecl = BaseDecl->getDefinition()) &&
findCircularInheritance(Class, BaseDecl))) {
Diag(BaseLoc, diag::err_circular_inheritance)
<< BaseType << Context.getTypeDeclType(Class);
if (BaseDecl->getCanonicalDecl() != Class->getCanonicalDecl())
Diag(BaseDecl->getLocation(), diag::note_previous_decl)
<< BaseType;
return nullptr;
}
}
return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
Class->getTagKind() == TTK_Class,
Access, TInfo, EllipsisLoc);
}
// Base specifiers must be record types.
if (!BaseType->isRecordType()) {
Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange;
return nullptr;
}
// C++ [class.union]p1:
// A union shall not be used as a base class.
if (BaseType->isUnionType()) {
Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange;
return nullptr;
}
// For the MS ABI, propagate DLL attributes to base class templates.
if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
if (Attr *ClassAttr = getDLLAttr(Class)) {
if (auto *BaseTemplate = dyn_cast_or_null<ClassTemplateSpecializationDecl>(
BaseType->getAsCXXRecordDecl())) {
propagateDLLAttrToBaseClassTemplate(*this, Class, ClassAttr,
BaseTemplate, BaseLoc);
}
}
}
// C++ [class.derived]p2:
// The class-name in a base-specifier shall not be an incompletely
// defined class.
if (RequireCompleteType(BaseLoc, BaseType,
diag::err_incomplete_base_class, SpecifierRange)) {
Class->setInvalidDecl();
return nullptr;
}
// If the base class is polymorphic or isn't empty, the new one is/isn't, too.
RecordDecl *BaseDecl = BaseType->getAs<RecordType>()->getDecl();
assert(BaseDecl && "Record type has no declaration");
BaseDecl = BaseDecl->getDefinition();
assert(BaseDecl && "Base type is not incomplete, but has no definition");
CXXRecordDecl *CXXBaseDecl = cast<CXXRecordDecl>(BaseDecl);
assert(CXXBaseDecl && "Base type is not a C++ type");
// A class which contains a flexible array member is not suitable for use as a
// base class:
// - If the layout determines that a base comes before another base,
// the flexible array member would index into the subsequent base.
// - If the layout determines that base comes before the derived class,
// the flexible array member would index into the derived class.
if (CXXBaseDecl->hasFlexibleArrayMember()) {
Diag(BaseLoc, diag::err_base_class_has_flexible_array_member)
<< CXXBaseDecl->getDeclName();
return nullptr;
}
// C++ [class]p3:
// If a class is marked final and it appears as a base-type-specifier in
// base-clause, the program is ill-formed.
if (FinalAttr *FA = CXXBaseDecl->getAttr<FinalAttr>()) {
Diag(BaseLoc, diag::err_class_marked_final_used_as_base)
<< CXXBaseDecl->getDeclName()
<< FA->isSpelledAsSealed();
Diag(CXXBaseDecl->getLocation(), diag::note_entity_declared_at)
<< CXXBaseDecl->getDeclName() << FA->getRange();
return nullptr;
}
if (BaseDecl->isInvalidDecl())
Class->setInvalidDecl();
// Create the base specifier.
return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
Class->getTagKind() == TTK_Class,
Access, TInfo, EllipsisLoc);
}
/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is
/// one entry in the base class list of a class specifier, for
/// example:
/// class foo : public bar, virtual private baz {
/// 'public bar' and 'virtual private baz' are each base-specifiers.
BaseResult
Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
ParsedAttributes &Attributes,
bool Virtual, AccessSpecifier Access,
ParsedType basetype, SourceLocation BaseLoc,
SourceLocation EllipsisLoc) {
if (!classdecl)
return true;
AdjustDeclIfTemplate(classdecl);
CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(classdecl);
if (!Class)
return true;
// We haven't yet attached the base specifiers.
Class->setIsParsingBaseSpecifiers();
// We do not support any C++11 attributes on base-specifiers yet.
// Diagnose any attributes we see.
if (!Attributes.empty()) {
for (AttributeList *Attr = Attributes.getList(); Attr;
Attr = Attr->getNext()) {
if (Attr->isInvalid() ||
Attr->getKind() == AttributeList::IgnoredAttribute)
continue;
Diag(Attr->getLoc(),
Attr->getKind() == AttributeList::UnknownAttribute
? diag::warn_unknown_attribute_ignored
: diag::err_base_specifier_attribute)
<< Attr->getName();
}
}
TypeSourceInfo *TInfo = nullptr;
GetTypeFromParser(basetype, &TInfo);
if (EllipsisLoc.isInvalid() &&
DiagnoseUnexpandedParameterPack(SpecifierRange.getBegin(), TInfo,
UPPC_BaseType))
return true;
if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange,
Virtual, Access, TInfo,
EllipsisLoc))
return BaseSpec;
else
Class->setInvalidDecl();
return true;
}
/// \brief Performs the actual work of attaching the given base class
/// specifiers to a C++ class.
bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class, CXXBaseSpecifier **Bases,
unsigned NumBases) {
if (NumBases == 0)
return false;
// Used to keep track of which base types we have already seen, so
// that we can properly diagnose redundant direct base types. Note
// that the key is always the unqualified canonical type of the base
// class.
std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes;
// Copy non-redundant base specifiers into permanent storage.
unsigned NumGoodBases = 0;
bool Invalid = false;
for (unsigned idx = 0; idx < NumBases; ++idx) {
QualType NewBaseType
= Context.getCanonicalType(Bases[idx]->getType());
NewBaseType = NewBaseType.getLocalUnqualifiedType();
CXXBaseSpecifier *&KnownBase = KnownBaseTypes[NewBaseType];
if (KnownBase) {
// C++ [class.mi]p3:
// A class shall not be specified as a direct base class of a
// derived class more than once.
Diag(Bases[idx]->getLocStart(),
diag::err_duplicate_base_class)
<< KnownBase->getType()
<< Bases[idx]->getSourceRange();
// Delete the duplicate base class specifier; we're going to
// overwrite its pointer later.
Context.Deallocate(Bases[idx]);
Invalid = true;
} else {
// Okay, add this new base class.
KnownBase = Bases[idx];
Bases[NumGoodBases++] = Bases[idx];
if (const RecordType *Record = NewBaseType->getAs<RecordType>()) {
const CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
if (Class->isInterface() &&
(!RD->isInterface() ||
KnownBase->getAccessSpecifier() != AS_public)) {
// The Microsoft extension __interface does not permit bases that
// are not themselves public interfaces.
Diag(KnownBase->getLocStart(), diag::err_invalid_base_in_interface)
<< getRecordDiagFromTagKind(RD->getTagKind()) << RD->getName()
<< RD->getSourceRange();
Invalid = true;
}
if (RD->hasAttr<WeakAttr>())
Class->addAttr(WeakAttr::CreateImplicit(Context));
}
}
}
// Attach the remaining base class specifiers to the derived class.
Class->setBases(Bases, NumGoodBases);
// Delete the remaining (good) base class specifiers, since their
// data has been copied into the CXXRecordDecl.
for (unsigned idx = 0; idx < NumGoodBases; ++idx)
Context.Deallocate(Bases[idx]);
return Invalid;
}
/// ActOnBaseSpecifiers - Attach the given base specifiers to the
/// class, after checking whether there are any duplicate base
/// classes.
void Sema::ActOnBaseSpecifiers(Decl *ClassDecl, CXXBaseSpecifier **Bases,
unsigned NumBases) {
if (!ClassDecl || !Bases || !NumBases)
return;
AdjustDeclIfTemplate(ClassDecl);
AttachBaseSpecifiers(cast<CXXRecordDecl>(ClassDecl), Bases, NumBases);
}
/// \brief Determine whether the type \p Derived is a C++ class that is
/// derived from the type \p Base.
bool Sema::IsDerivedFrom(QualType Derived, QualType Base) {
if (!getLangOpts().CPlusPlus)
return false;
CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
if (!DerivedRD)
return false;
CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
if (!BaseRD)
return false;
// If either the base or the derived type is invalid, don't try to
// check whether one is derived from the other.
if (BaseRD->isInvalidDecl() || DerivedRD->isInvalidDecl())
return false;
// FIXME: instantiate DerivedRD if necessary. We need a PoI for this.
return DerivedRD->hasDefinition() && DerivedRD->isDerivedFrom(BaseRD);
}
/// \brief Determine whether the type \p Derived is a C++ class that is
/// derived from the type \p Base.
bool Sema::IsDerivedFrom(QualType Derived, QualType Base, CXXBasePaths &Paths) {
if (!getLangOpts().CPlusPlus)
return false;
CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
if (!DerivedRD)
return false;
CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
if (!BaseRD)
return false;
return DerivedRD->isDerivedFrom(BaseRD, Paths);
}
void Sema::BuildBasePathArray(const CXXBasePaths &Paths,
CXXCastPath &BasePathArray) {
assert(BasePathArray.empty() && "Base path array must be empty!");
assert(Paths.isRecordingPaths() && "Must record paths!");
const CXXBasePath &Path = Paths.front();
// We first go backward and check if we have a virtual base.
// FIXME: It would be better if CXXBasePath had the base specifier for
// the nearest virtual base.
unsigned Start = 0;
for (unsigned I = Path.size(); I != 0; --I) {
if (Path[I - 1].Base->isVirtual()) {
Start = I - 1;
break;
}
}
// Now add all bases.
for (unsigned I = Start, E = Path.size(); I != E; ++I)
BasePathArray.push_back(const_cast<CXXBaseSpecifier*>(Path[I].Base));
}
/// \brief Determine whether the given base path includes a virtual
/// base class.
bool Sema::BasePathInvolvesVirtualBase(const CXXCastPath &BasePath) {
for (CXXCastPath::const_iterator B = BasePath.begin(),
BEnd = BasePath.end();
B != BEnd; ++B)
if ((*B)->isVirtual())
return true;
return false;
}
/// CheckDerivedToBaseConversion - Check whether the Derived-to-Base
/// conversion (where Derived and Base are class types) is
/// well-formed, meaning that the conversion is unambiguous (and
/// that all of the base classes are accessible). Returns true
/// and emits a diagnostic if the code is ill-formed, returns false
/// otherwise. Loc is the location where this routine should point to
/// if there is an error, and Range is the source range to highlight
/// if there is an error.
bool
Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
unsigned InaccessibleBaseID,
unsigned AmbigiousBaseConvID,
SourceLocation Loc, SourceRange Range,
DeclarationName Name,
CXXCastPath *BasePath) {
// First, determine whether the path from Derived to Base is
// ambiguous. This is slightly more expensive than checking whether
// the Derived to Base conversion exists, because here we need to
// explore multiple paths to determine if there is an ambiguity.
CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
/*DetectVirtual=*/false);
bool DerivationOkay = IsDerivedFrom(Derived, Base, Paths);
assert(DerivationOkay &&
"Can only be used with a derived-to-base conversion");
(void)DerivationOkay;
if (!Paths.isAmbiguous(Context.getCanonicalType(Base).getUnqualifiedType())) {
if (InaccessibleBaseID) {
// Check that the base class can be accessed.
switch (CheckBaseClassAccess(Loc, Base, Derived, Paths.front(),
InaccessibleBaseID)) {
case AR_inaccessible:
return true;
case AR_accessible:
case AR_dependent:
case AR_delayed:
break;
}
}
// Build a base path if necessary.
if (BasePath)
BuildBasePathArray(Paths, *BasePath);
return false;
}
if (AmbigiousBaseConvID) {
// We know that the derived-to-base conversion is ambiguous, and
// we're going to produce a diagnostic. Perform the derived-to-base
// search just one more time to compute all of the possible paths so
// that we can print them out. This is more expensive than any of
// the previous derived-to-base checks we've done, but at this point
// performance isn't as much of an issue.
Paths.clear();
Paths.setRecordingPaths(true);
bool StillOkay = IsDerivedFrom(Derived, Base, Paths);
assert(StillOkay && "Can only be used with a derived-to-base conversion");
(void)StillOkay;
// Build up a textual representation of the ambiguous paths, e.g.,
// D -> B -> A, that will be used to illustrate the ambiguous
// conversions in the diagnostic. We only print one of the paths
// to each base class subobject.
std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths);
Diag(Loc, AmbigiousBaseConvID)
<< Derived << Base << PathDisplayStr << Range << Name;
}
return true;
}
bool
Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
SourceLocation Loc, SourceRange Range,
CXXCastPath *BasePath,
bool IgnoreAccess) {
return CheckDerivedToBaseConversion(Derived, Base,
IgnoreAccess ? 0
: diag::err_upcast_to_inaccessible_base,
diag::err_ambiguous_derived_to_base_conv,
Loc, Range, DeclarationName(),
BasePath);
}
/// @brief Builds a string representing ambiguous paths from a
/// specific derived class to different subobjects of the same base
/// class.
///
/// This function builds a string that can be used in error messages
/// to show the different paths that one can take through the
/// inheritance hierarchy to go from the derived class to different
/// subobjects of a base class. The result looks something like this:
/// @code
/// struct D -> struct B -> struct A
/// struct D -> struct C -> struct A
/// @endcode
std::string Sema::getAmbiguousPathsDisplayString(CXXBasePaths &Paths) {
std::string PathDisplayStr;
std::set<unsigned> DisplayedPaths;
for (CXXBasePaths::paths_iterator Path = Paths.begin();
Path != Paths.end(); ++Path) {
if (DisplayedPaths.insert(Path->back().SubobjectNumber).second) {
// We haven't displayed a path to this particular base
// class subobject yet.
PathDisplayStr += "\n ";
PathDisplayStr += Context.getTypeDeclType(Paths.getOrigin()).getAsString();
for (CXXBasePath::const_iterator Element = Path->begin();
Element != Path->end(); ++Element)
PathDisplayStr += " -> " + Element->Base->getType().getAsString();
}
}
return PathDisplayStr;
}
//===----------------------------------------------------------------------===//
// C++ class member Handling
//===----------------------------------------------------------------------===//
/// ActOnAccessSpecifier - Parsed an access specifier followed by a colon.
bool Sema::ActOnAccessSpecifier(AccessSpecifier Access,
SourceLocation ASLoc,
SourceLocation ColonLoc,
AttributeList *Attrs) {
assert(Access != AS_none && "Invalid kind for syntactic access specifier!");
AccessSpecDecl *ASDecl = AccessSpecDecl::Create(Context, Access, CurContext,
ASLoc, ColonLoc);
CurContext->addHiddenDecl(ASDecl);
return ProcessAccessDeclAttributeList(ASDecl, Attrs);
}
/// CheckOverrideControl - Check C++11 override control semantics.
void Sema::CheckOverrideControl(NamedDecl *D) {
if (D->isInvalidDecl())
return;
// We only care about "override" and "final" declarations.
if (!D->hasAttr<OverrideAttr>() && !D->hasAttr<FinalAttr>())
return;
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
// We can't check dependent instance methods.
if (MD && MD->isInstance() &&
(MD->getParent()->hasAnyDependentBases() ||
MD->getType()->isDependentType()))
return;
if (MD && !MD->isVirtual()) {
// If we have a non-virtual method, check if if hides a virtual method.
// (In that case, it's most likely the method has the wrong type.)
SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
FindHiddenVirtualMethods(MD, OverloadedMethods);
if (!OverloadedMethods.empty()) {
if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
Diag(OA->getLocation(),
diag::override_keyword_hides_virtual_member_function)
<< "override" << (OverloadedMethods.size() > 1);
} else if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
Diag(FA->getLocation(),
diag::override_keyword_hides_virtual_member_function)
<< (FA->isSpelledAsSealed() ? "sealed" : "final")
<< (OverloadedMethods.size() > 1);
}
NoteHiddenVirtualMethods(MD, OverloadedMethods);
MD->setInvalidDecl();
return;
}
// Fall through into the general case diagnostic.
// FIXME: We might want to attempt typo correction here.
}
if (!MD || !MD->isVirtual()) {
if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
Diag(OA->getLocation(),
diag::override_keyword_only_allowed_on_virtual_member_functions)
<< "override" << FixItHint::CreateRemoval(OA->getLocation());
D->dropAttr<OverrideAttr>();
}
if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
Diag(FA->getLocation(),
diag::override_keyword_only_allowed_on_virtual_member_functions)
<< (FA->isSpelledAsSealed() ? "sealed" : "final")
<< FixItHint::CreateRemoval(FA->getLocation());
D->dropAttr<FinalAttr>();
}
return;
}
// C++11 [class.virtual]p5:
// If a virtual function is marked with the virt-specifier override and
// does not override a member function of a base class, the program is
// ill-formed.
bool HasOverriddenMethods =
MD->begin_overridden_methods() != MD->end_overridden_methods();
if (MD->hasAttr<OverrideAttr>() && !HasOverriddenMethods)
Diag(MD->getLocation(), diag::err_function_marked_override_not_overriding)
<< MD->getDeclName();
}
/// CheckIfOverriddenFunctionIsMarkedFinal - Checks whether a virtual member
/// function overrides a virtual member function marked 'final', according to
/// C++11 [class.virtual]p4.
bool Sema::CheckIfOverriddenFunctionIsMarkedFinal(const CXXMethodDecl *New,
const CXXMethodDecl *Old) {
FinalAttr *FA = Old->getAttr<FinalAttr>();
if (!FA)
return false;
Diag(New->getLocation(), diag::err_final_function_overridden)
<< New->getDeclName()
<< FA->isSpelledAsSealed();
Diag(Old->getLocation(), diag::note_overridden_virtual_function);
return true;
}
static bool InitializationHasSideEffects(const FieldDecl &FD) {
const Type *T = FD.getType()->getBaseElementTypeUnsafe();
// FIXME: Destruction of ObjC lifetime types has side-effects.
if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
return !RD->isCompleteDefinition() ||
!RD->hasTrivialDefaultConstructor() ||
!RD->hasTrivialDestructor();
return false;
}
static AttributeList *getMSPropertyAttr(AttributeList *list) {
for (AttributeList *it = list; it != nullptr; it = it->getNext())
if (it->isDeclspecPropertyAttribute())
return it;
return nullptr;
}
/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member
/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the
/// bitfield width if there is one, 'InitExpr' specifies the initializer if
/// one has been parsed, and 'InitStyle' is set if an in-class initializer is
/// present (but parsing it has been deferred).
NamedDecl *
Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D,
MultiTemplateParamsArg TemplateParameterLists,
Expr *BW, const VirtSpecifiers &VS,
InClassInitStyle InitStyle) {
const DeclSpec &DS = D.getDeclSpec();
DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
DeclarationName Name = NameInfo.getName();
SourceLocation Loc = NameInfo.getLoc();
// For anonymous bitfields, the location should point to the type.
if (Loc.isInvalid())
Loc = D.getLocStart();
Expr *BitWidth = static_cast<Expr*>(BW);
assert(isa<CXXRecordDecl>(CurContext));
assert(!DS.isFriendSpecified());
bool isFunc = D.isDeclarationOfFunction();
if (cast<CXXRecordDecl>(CurContext)->isInterface()) {
// The Microsoft extension __interface only permits public member functions
// and prohibits constructors, destructors, operators, non-public member
// functions, static methods and data members.
unsigned InvalidDecl;
bool ShowDeclName = true;
if (!isFunc)
InvalidDecl = (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) ? 0 : 1;
else if (AS != AS_public)
InvalidDecl = 2;
else if (DS.getStorageClassSpec() == DeclSpec::SCS_static)
InvalidDecl = 3;
else switch (Name.getNameKind()) {
case DeclarationName::CXXConstructorName:
InvalidDecl = 4;
ShowDeclName = false;
break;
case DeclarationName::CXXDestructorName:
InvalidDecl = 5;
ShowDeclName = false;
break;
case DeclarationName::CXXOperatorName:
case DeclarationName::CXXConversionFunctionName:
InvalidDecl = 6;
break;
default:
InvalidDecl = 0;
break;
}
if (InvalidDecl) {
if (ShowDeclName)
Diag(Loc, diag::err_invalid_member_in_interface)
<< (InvalidDecl-1) << Name;
else
Diag(Loc, diag::err_invalid_member_in_interface)
<< (InvalidDecl-1) << "";
return nullptr;
}
}
// C++ 9.2p6: A member shall not be declared to have automatic storage
// duration (auto, register) or with the extern storage-class-specifier.
// C++ 7.1.1p8: The mutable specifier can be applied only to names of class
// data members and cannot be applied to names declared const or static,
// and cannot be applied to reference members.
switch (DS.getStorageClassSpec()) {
case DeclSpec::SCS_unspecified:
case DeclSpec::SCS_typedef:
case DeclSpec::SCS_static:
break;
case DeclSpec::SCS_mutable:
if (isFunc) {
Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function);
// FIXME: It would be nicer if the keyword was ignored only for this
// declarator. Otherwise we could get follow-up errors.
D.getMutableDeclSpec().ClearStorageClassSpecs();
}
break;
default:
Diag(DS.getStorageClassSpecLoc(),
diag::err_storageclass_invalid_for_member);
D.getMutableDeclSpec().ClearStorageClassSpecs();
break;
}
bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified ||
DS.getStorageClassSpec() == DeclSpec::SCS_mutable) &&
!isFunc);
if (DS.isConstexprSpecified() && isInstField) {
SemaDiagnosticBuilder B =
Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr_member);
SourceLocation ConstexprLoc = DS.getConstexprSpecLoc();
if (InitStyle == ICIS_NoInit) {
B << 0 << 0;
if (D.getDeclSpec().getTypeQualifiers() & DeclSpec::TQ_const)
B << FixItHint::CreateRemoval(ConstexprLoc);
else {
B << FixItHint::CreateReplacement(ConstexprLoc, "const");
D.getMutableDeclSpec().ClearConstexprSpec();
const char *PrevSpec;
unsigned DiagID;
bool Failed = D.getMutableDeclSpec().SetTypeQual(
DeclSpec::TQ_const, ConstexprLoc, PrevSpec, DiagID, getLangOpts());
(void)Failed;
assert(!Failed && "Making a constexpr member const shouldn't fail");
}
} else {
B << 1;
const char *PrevSpec;
unsigned DiagID;
if (D.getMutableDeclSpec().SetStorageClassSpec(
*this, DeclSpec::SCS_static, ConstexprLoc, PrevSpec, DiagID,
Context.getPrintingPolicy())) {
assert(DS.getStorageClassSpec() == DeclSpec::SCS_mutable &&
"This is the only DeclSpec that should fail to be applied");
B << 1;
} else {
B << 0 << FixItHint::CreateInsertion(ConstexprLoc, "static ");
isInstField = false;
}
}
}
NamedDecl *Member;
if (isInstField) {
CXXScopeSpec &SS = D.getCXXScopeSpec();
// Data members must have identifiers for names.
if (!Name.isIdentifier()) {
Diag(Loc, diag::err_bad_variable_name)
<< Name;
return nullptr;
}
IdentifierInfo *II = Name.getAsIdentifierInfo();
// Member field could not be with "template" keyword.
// So TemplateParameterLists should be empty in this case.
if (TemplateParameterLists.size()) {
TemplateParameterList* TemplateParams = TemplateParameterLists[0];
if (TemplateParams->size()) {
// There is no such thing as a member field template.
Diag(D.getIdentifierLoc(), diag::err_template_member)
<< II
<< SourceRange(TemplateParams->getTemplateLoc(),
TemplateParams->getRAngleLoc());
} else {
// There is an extraneous 'template<>' for this member.
Diag(TemplateParams->getTemplateLoc(),
diag::err_template_member_noparams)
<< II
<< SourceRange(TemplateParams->getTemplateLoc(),
TemplateParams->getRAngleLoc());
}
return nullptr;
}
if (SS.isSet() && !SS.isInvalid()) {
// The user provided a superfluous scope specifier inside a class
// definition:
//
// class X {
// int X::member;
// };
if (DeclContext *DC = computeDeclContext(SS, false))
diagnoseQualifiedDeclaration(SS, DC, Name, D.getIdentifierLoc());
else
Diag(D.getIdentifierLoc(), diag::err_member_qualification)
<< Name << SS.getRange();
SS.clear();
}
AttributeList *MSPropertyAttr =
getMSPropertyAttr(D.getDeclSpec().getAttributes().getList());
if (MSPropertyAttr) {
Member = HandleMSProperty(S, cast<CXXRecordDecl>(CurContext), Loc, D,
BitWidth, InitStyle, AS, MSPropertyAttr);
if (!Member)
return nullptr;
isInstField = false;
} else {
Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D,
BitWidth, InitStyle, AS);
assert(Member && "HandleField never returns null");
}
} else {
assert(InitStyle == ICIS_NoInit || D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static);
Member = HandleDeclarator(S, D, TemplateParameterLists);
if (!Member)
return nullptr;
// Non-instance-fields can't have a bitfield.
if (BitWidth) {
if (Member->isInvalidDecl()) {
// don't emit another diagnostic.
} else if (isa<VarDecl>(Member)) {
// C++ 9.6p3: A bit-field shall not be a static member.
// "static member 'A' cannot be a bit-field"
Diag(Loc, diag::err_static_not_bitfield)
<< Name << BitWidth->getSourceRange();
} else if (isa<TypedefDecl>(Member)) {
// "typedef member 'x' cannot be a bit-field"
Diag(Loc, diag::err_typedef_not_bitfield)
<< Name << BitWidth->getSourceRange();
} else {
// A function typedef ("typedef int f(); f a;").
// C++ 9.6p3: A bit-field shall have integral or enumeration type.
Diag(Loc, diag::err_not_integral_type_bitfield)
<< Name << cast<ValueDecl>(Member)->getType()
<< BitWidth->getSourceRange();
}
BitWidth = nullptr;
Member->setInvalidDecl();
}
Member->setAccess(AS);
// If we have declared a member function template or static data member
// template, set the access of the templated declaration as well.
if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Member))
FunTmpl->getTemplatedDecl()->setAccess(AS);
else if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(Member))
VarTmpl->getTemplatedDecl()->setAccess(AS);
}
if (VS.isOverrideSpecified())
Member->addAttr(new (Context) OverrideAttr(VS.getOverrideLoc(), Context, 0));
if (VS.isFinalSpecified())
Member->addAttr(new (Context) FinalAttr(VS.getFinalLoc(), Context,
VS.isFinalSpelledSealed()));
if (VS.getLastLocation().isValid()) {
// Update the end location of a method that has a virt-specifiers.
if (CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Member))
MD->setRangeEnd(VS.getLastLocation());
}
CheckOverrideControl(Member);
assert((Name || isInstField) && "No identifier for non-field ?");
if (isInstField) {
FieldDecl *FD = cast<FieldDecl>(Member);
FieldCollector->Add(FD);
if (!Diags.isIgnored(diag::warn_unused_private_field, FD->getLocation())) {
// Remember all explicit private FieldDecls that have a name, no side
// effects and are not part of a dependent type declaration.
if (!FD->isImplicit() && FD->getDeclName() &&
FD->getAccess() == AS_private &&
!FD->hasAttr<UnusedAttr>() &&
!FD->getParent()->isDependentContext() &&
!InitializationHasSideEffects(*FD))
UnusedPrivateFields.insert(FD);
}
}
return Member;
}
namespace {
class UninitializedFieldVisitor
: public EvaluatedExprVisitor<UninitializedFieldVisitor> {
Sema &S;
// List of Decls to generate a warning on. Also remove Decls that become
// initialized.
llvm::SmallPtrSet<ValueDecl*, 4> &Decls;
// If non-null, add a note to the warning pointing back to the constructor.
const CXXConstructorDecl *Constructor;
public:
typedef EvaluatedExprVisitor<UninitializedFieldVisitor> Inherited;
UninitializedFieldVisitor(Sema &S,
llvm::SmallPtrSet<ValueDecl*, 4> &Decls,
const CXXConstructorDecl *Constructor)
: Inherited(S.Context), S(S), Decls(Decls),
Constructor(Constructor) { }
void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly) {
if (isa<EnumConstantDecl>(ME->getMemberDecl()))
return;
// FieldME is the inner-most MemberExpr that is not an anonymous struct
// or union.
MemberExpr *FieldME = ME;
Expr *Base = ME;
while (isa<MemberExpr>(Base)) {
ME = cast<MemberExpr>(Base);
if (isa<VarDecl>(ME->getMemberDecl()))
return;
if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
if (!FD->isAnonymousStructOrUnion())
FieldME = ME;
Base = ME->getBase();
}
if (!isa<CXXThisExpr>(Base))
return;
ValueDecl* FoundVD = FieldME->getMemberDecl();
if (!Decls.count(FoundVD))
return;
const bool IsReference = FoundVD->getType()->isReferenceType();
// Prevent double warnings on use of unbounded references.
if (IsReference != CheckReferenceOnly)
return;
unsigned diag = IsReference
? diag::warn_reference_field_is_uninit
: diag::warn_field_is_uninit;
S.Diag(FieldME->getExprLoc(), diag) << FoundVD;
if (Constructor)
S.Diag(Constructor->getLocation(),
diag::note_uninit_in_this_constructor)
<< (Constructor->isDefaultConstructor() && Constructor->isImplicit());
}
void HandleValue(Expr *E) {
E = E->IgnoreParens();
if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
HandleMemberExpr(ME, false /*CheckReferenceOnly*/);
return;
}
if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
HandleValue(CO->getTrueExpr());
HandleValue(CO->getFalseExpr());
return;
}
if (BinaryConditionalOperator *BCO =
dyn_cast<BinaryConditionalOperator>(E)) {
HandleValue(BCO->getCommon());
HandleValue(BCO->getFalseExpr());
return;
}
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
switch (BO->getOpcode()) {
default:
return;
case(BO_PtrMemD):
case(BO_PtrMemI):
HandleValue(BO->getLHS());
return;
case(BO_Comma):
HandleValue(BO->getRHS());
return;
}
}
}
void VisitMemberExpr(MemberExpr *ME) {
// All uses of unbounded reference fields will warn.
HandleMemberExpr(ME, true /*CheckReferenceOnly*/);
Inherited::VisitMemberExpr(ME);
}
void VisitImplicitCastExpr(ImplicitCastExpr *E) {
if (E->getCastKind() == CK_LValueToRValue)
HandleValue(E->getSubExpr());
Inherited::VisitImplicitCastExpr(E);
}
void VisitCXXConstructExpr(CXXConstructExpr *E) {
if (E->getConstructor()->isCopyConstructor())
if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(E->getArg(0)))
if (ICE->getCastKind() == CK_NoOp)
if (MemberExpr *ME = dyn_cast<MemberExpr>(ICE->getSubExpr()))
HandleMemberExpr(ME, false /*CheckReferenceOnly*/);
Inherited::VisitCXXConstructExpr(E);
}
void VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
Expr *Callee = E->getCallee();
if (isa<MemberExpr>(Callee))
HandleValue(Callee);
Inherited::VisitCXXMemberCallExpr(E);
}
void VisitBinaryOperator(BinaryOperator *E) {
// If a field assignment is detected, remove the field from the
// uninitiailized field set.
if (E->getOpcode() == BO_Assign)
if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getLHS()))
if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
if (!FD->getType()->isReferenceType())
Decls.erase(FD);
Inherited::VisitBinaryOperator(E);
}
};
static void CheckInitExprContainsUninitializedFields(
Sema &S, Expr *E, llvm::SmallPtrSet<ValueDecl*, 4> &Decls,
const CXXConstructorDecl *Constructor) {
if (Decls.size() == 0)
return;
if (!E)
return;
if (CXXDefaultInitExpr *Default = dyn_cast<CXXDefaultInitExpr>(E)) {
E = Default->getExpr();
if (!E)
return;
// In class initializers will point to the constructor.
UninitializedFieldVisitor(S, Decls, Constructor).Visit(E);
} else {
UninitializedFieldVisitor(S, Decls, nullptr).Visit(E);
}
}
// Diagnose value-uses of fields to initialize themselves, e.g.
// foo(foo)
// where foo is not also a parameter to the constructor.
// Also diagnose across field uninitialized use such as
// x(y), y(x)
// TODO: implement -Wuninitialized and fold this into that framework.
static void DiagnoseUninitializedFields(
Sema &SemaRef, const CXXConstructorDecl *Constructor) {
if (SemaRef.getDiagnostics().isIgnored(diag::warn_field_is_uninit,
Constructor->getLocation())) {
return;
}
if (Constructor->isInvalidDecl())
return;
const CXXRecordDecl *RD = Constructor->getParent();
// Holds fields that are uninitialized.
llvm::SmallPtrSet<ValueDecl*, 4> UninitializedFields;
// At the beginning, all fields are uninitialized.
for (auto *I : RD->decls()) {
if (auto *FD = dyn_cast<FieldDecl>(I)) {
UninitializedFields.insert(FD);
} else if (auto *IFD = dyn_cast<IndirectFieldDecl>(I)) {
UninitializedFields.insert(IFD->getAnonField());
}
}
for (const auto *FieldInit : Constructor->inits()) {
Expr *InitExpr = FieldInit->getInit();
CheckInitExprContainsUninitializedFields(
SemaRef, InitExpr, UninitializedFields, Constructor);
if (FieldDecl *Field = FieldInit->getAnyMember())
UninitializedFields.erase(Field);
}
}
} // namespace
/// \brief Enter a new C++ default initializer scope. After calling this, the
/// caller must call \ref ActOnFinishCXXInClassMemberInitializer, even if
/// parsing or instantiating the initializer failed.
void Sema::ActOnStartCXXInClassMemberInitializer() {
// Create a synthetic function scope to represent the call to the constructor
// that notionally surrounds a use of this initializer.
PushFunctionScope();
}
/// \brief This is invoked after parsing an in-class initializer for a
/// non-static C++ class member, and after instantiating an in-class initializer
/// in a class template. Such actions are deferred until the class is complete.
void Sema::ActOnFinishCXXInClassMemberInitializer(Decl *D,
SourceLocation InitLoc,
Expr *InitExpr) {
// Pop the notional constructor scope we created earlier.
PopFunctionScopeInfo(nullptr, D);
FieldDecl *FD = cast<FieldDecl>(D);
assert(FD->getInClassInitStyle() != ICIS_NoInit &&
"must set init style when field is created");
if (!InitExpr) {
FD->setInvalidDecl();
FD->removeInClassInitializer();
return;
}
if (DiagnoseUnexpandedParameterPack(InitExpr, UPPC_Initializer)) {
FD->setInvalidDecl();
FD->removeInClassInitializer();
return;
}
ExprResult Init = InitExpr;
if (!FD->getType()->isDependentType() && !InitExpr->isTypeDependent()) {
InitializedEntity Entity = InitializedEntity::InitializeMember(FD);
InitializationKind Kind = FD->getInClassInitStyle() == ICIS_ListInit
? InitializationKind::CreateDirectList(InitExpr->getLocStart())
: InitializationKind::CreateCopy(InitExpr->getLocStart(), InitLoc);
InitializationSequence Seq(*this, Entity, Kind, InitExpr);
Init = Seq.Perform(*this, Entity, Kind, InitExpr);
if (Init.isInvalid()) {
FD->setInvalidDecl();
return;
}
}
// C++11 [class.base.init]p7:
// The initialization of each base and member constitutes a
// full-expression.
Init = ActOnFinishFullExpr(Init.get(), InitLoc);
if (Init.isInvalid()) {
FD->setInvalidDecl();
return;
}
InitExpr = Init.get();
FD->setInClassInitializer(InitExpr);
}
/// \brief Find the direct and/or virtual base specifiers that
/// correspond to the given base type, for use in base initialization
/// within a constructor.
static bool FindBaseInitializer(Sema &SemaRef,
CXXRecordDecl *ClassDecl,
QualType BaseType,
const CXXBaseSpecifier *&DirectBaseSpec,
const CXXBaseSpecifier *&VirtualBaseSpec) {
// First, check for a direct base class.
DirectBaseSpec = nullptr;
for (const auto &Base : ClassDecl->bases()) {
if (SemaRef.Context.hasSameUnqualifiedType(BaseType, Base.getType())) {
// We found a direct base of this type. That's what we're
// initializing.
DirectBaseSpec = &Base;
break;
}
}
// Check for a virtual base class.
// FIXME: We might be able to short-circuit this if we know in advance that
// there are no virtual bases.
VirtualBaseSpec = nullptr;
if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) {
// We haven't found a base yet; search the class hierarchy for a
// virtual base class.
CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
/*DetectVirtual=*/false);
if (SemaRef.IsDerivedFrom(SemaRef.Context.getTypeDeclType(ClassDecl),
BaseType, Paths)) {
for (CXXBasePaths::paths_iterator Path = Paths.begin();
Path != Paths.end(); ++Path) {
if (Path->back().Base->isVirtual()) {
VirtualBaseSpec = Path->back().Base;
break;
}
}
}
}
return DirectBaseSpec || VirtualBaseSpec;
}
/// \brief Handle a C++ member initializer using braced-init-list syntax.
MemInitResult
Sema::ActOnMemInitializer(Decl *ConstructorD,
Scope *S,
CXXScopeSpec &SS,
IdentifierInfo *MemberOrBase,
ParsedType TemplateTypeTy,
const DeclSpec &DS,
SourceLocation IdLoc,
Expr *InitList,
SourceLocation EllipsisLoc) {
return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
DS, IdLoc, InitList,
EllipsisLoc);
}
/// \brief Handle a C++ member initializer using parentheses syntax.
MemInitResult
Sema::ActOnMemInitializer(Decl *ConstructorD,
Scope *S,
CXXScopeSpec &SS,
IdentifierInfo *MemberOrBase,
ParsedType TemplateTypeTy,
const DeclSpec &DS,
SourceLocation IdLoc,
SourceLocation LParenLoc,
ArrayRef<Expr *> Args,
SourceLocation RParenLoc,
SourceLocation EllipsisLoc) {
Expr *List = new (Context) ParenListExpr(Context, LParenLoc,
Args, RParenLoc);
return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
DS, IdLoc, List, EllipsisLoc);
}
namespace {
// Callback to only accept typo corrections that can be a valid C++ member
// intializer: either a non-static field member or a base class.
class MemInitializerValidatorCCC : public CorrectionCandidateCallback {
public:
explicit MemInitializerValidatorCCC(CXXRecordDecl *ClassDecl)
: ClassDecl(ClassDecl) {}
bool ValidateCandidate(const TypoCorrection &candidate) override {
if (NamedDecl *ND = candidate.getCorrectionDecl()) {
if (FieldDecl *Member = dyn_cast<FieldDecl>(ND))
return Member->getDeclContext()->getRedeclContext()->Equals(ClassDecl);
return isa<TypeDecl>(ND);
}
return false;
}
private:
CXXRecordDecl *ClassDecl;
};
}
/// \brief Handle a C++ member initializer.
MemInitResult
Sema::BuildMemInitializer(Decl *ConstructorD,
Scope *S,
CXXScopeSpec &SS,
IdentifierInfo *MemberOrBase,
ParsedType TemplateTypeTy,
const DeclSpec &DS,
SourceLocation IdLoc,
Expr *Init,
SourceLocation EllipsisLoc) {
if (!ConstructorD)
return true;
AdjustDeclIfTemplate(ConstructorD);
CXXConstructorDecl *Constructor
= dyn_cast<CXXConstructorDecl>(ConstructorD);
if (!Constructor) {
// The user wrote a constructor initializer on a function that is
// not a C++ constructor. Ignore the error for now, because we may
// have more member initializers coming; we'll diagnose it just
// once in ActOnMemInitializers.
return true;
}
CXXRecordDecl *ClassDecl = Constructor->getParent();
// C++ [class.base.init]p2:
// Names in a mem-initializer-id are looked up in the scope of the
// constructor's class and, if not found in that scope, are looked
// up in the scope containing the constructor's definition.
// [Note: if the constructor's class contains a member with the
// same name as a direct or virtual base class of the class, a
// mem-initializer-id naming the member or base class and composed
// of a single identifier refers to the class member. A
// mem-initializer-id for the hidden base class may be specified
// using a qualified name. ]
if (!SS.getScopeRep() && !TemplateTypeTy) {
// Look for a member, first.
DeclContext::lookup_result Result
= ClassDecl->lookup(MemberOrBase);
if (!Result.empty()) {
ValueDecl *Member;
if ((Member = dyn_cast<FieldDecl>(Result.front())) ||
(Member = dyn_cast<IndirectFieldDecl>(Result.front()))) {
if (EllipsisLoc.isValid())
Diag(EllipsisLoc, diag::err_pack_expansion_member_init)
<< MemberOrBase
<< SourceRange(IdLoc, Init->getSourceRange().getEnd());
return BuildMemberInitializer(Member, Init, IdLoc);
}
}
}
// It didn't name a member, so see if it names a class.
QualType BaseType;
TypeSourceInfo *TInfo = nullptr;
if (TemplateTypeTy) {
BaseType = GetTypeFromParser(TemplateTypeTy, &TInfo);
} else if (DS.getTypeSpecType() == TST_decltype) {
BaseType = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
} else {
LookupResult R(*this, MemberOrBase, IdLoc, LookupOrdinaryName);
LookupParsedName(R, S, &SS);
TypeDecl *TyD = R.getAsSingle<TypeDecl>();
if (!TyD) {
if (R.isAmbiguous()) return true;
// We don't want access-control diagnostics here.
R.suppressDiagnostics();
if (SS.isSet() && isDependentScopeSpecifier(SS)) {
bool NotUnknownSpecialization = false;
DeclContext *DC = computeDeclContext(SS, false);
if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(DC))
NotUnknownSpecialization = !Record->hasAnyDependentBases();
if (!NotUnknownSpecialization) {
// When the scope specifier can refer to a member of an unknown
// specialization, we take it as a type name.
BaseType = CheckTypenameType(ETK_None, SourceLocation(),
SS.getWithLocInContext(Context),
*MemberOrBase, IdLoc);
if (BaseType.isNull())
return true;
R.clear();
R.setLookupName(MemberOrBase);
}
}
// If no results were found, try to correct typos.
TypoCorrection Corr;
MemInitializerValidatorCCC Validator(ClassDecl);
if (R.empty() && BaseType.isNull() &&
(Corr = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
Validator, CTK_ErrorRecovery, ClassDecl))) {
if (FieldDecl *Member = Corr.getCorrectionDeclAs<FieldDecl>()) {
// We have found a non-static data member with a similar
// name to what was typed; complain and initialize that
// member.
diagnoseTypo(Corr,
PDiag(diag::err_mem_init_not_member_or_class_suggest)
<< MemberOrBase << true);
return BuildMemberInitializer(Member, Init, IdLoc);
} else if (TypeDecl *Type = Corr.getCorrectionDeclAs<TypeDecl>()) {
const CXXBaseSpecifier *DirectBaseSpec;
const CXXBaseSpecifier *VirtualBaseSpec;
if (FindBaseInitializer(*this, ClassDecl,
Context.getTypeDeclType(Type),
DirectBaseSpec, VirtualBaseSpec)) {
// We have found a direct or virtual base class with a
// similar name to what was typed; complain and initialize
// that base class.
diagnoseTypo(Corr,
PDiag(diag::err_mem_init_not_member_or_class_suggest)
<< MemberOrBase << false,
PDiag() /*Suppress note, we provide our own.*/);
const CXXBaseSpecifier *BaseSpec = DirectBaseSpec ? DirectBaseSpec
: VirtualBaseSpec;
Diag(BaseSpec->getLocStart(),
diag::note_base_class_specified_here)
<< BaseSpec->getType()
<< BaseSpec->getSourceRange();
TyD = Type;
}
}
}
if (!TyD && BaseType.isNull()) {
Diag(IdLoc, diag::err_mem_init_not_member_or_class)
<< MemberOrBase << SourceRange(IdLoc,Init->getSourceRange().getEnd());
return true;
}
}
if (BaseType.isNull()) {
BaseType = Context.getTypeDeclType(TyD);
if (SS.isSet())
// FIXME: preserve source range information
BaseType = Context.getElaboratedType(ETK_None, SS.getScopeRep(),
BaseType);
}
}
if (!TInfo)
TInfo = Context.getTrivialTypeSourceInfo(BaseType, IdLoc);
return BuildBaseInitializer(BaseType, TInfo, Init, ClassDecl, EllipsisLoc);
}
/// Checks a member initializer expression for cases where reference (or
/// pointer) members are bound to by-value parameters (or their addresses).
static void CheckForDanglingReferenceOrPointer(Sema &S, ValueDecl *Member,
Expr *Init,
SourceLocation IdLoc) {
QualType MemberTy = Member->getType();
// We only handle pointers and references currently.
// FIXME: Would this be relevant for ObjC object pointers? Or block pointers?
if (!MemberTy->isReferenceType() && !MemberTy->isPointerType())
return;
const bool IsPointer = MemberTy->isPointerType();
if (IsPointer) {
if (const UnaryOperator *Op
= dyn_cast<UnaryOperator>(Init->IgnoreParenImpCasts())) {
// The only case we're worried about with pointers requires taking the
// address.
if (Op->getOpcode() != UO_AddrOf)
return;
Init = Op->getSubExpr();
} else {
// We only handle address-of expression initializers for pointers.
return;
}
}
if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Init->IgnoreParens())) {
// We only warn when referring to a non-reference parameter declaration.
const ParmVarDecl *Parameter = dyn_cast<ParmVarDecl>(DRE->getDecl());
if (!Parameter || Parameter->getType()->isReferenceType())
return;
S.Diag(Init->getExprLoc(),
IsPointer ? diag::warn_init_ptr_member_to_parameter_addr
: diag::warn_bind_ref_member_to_parameter)
<< Member << Parameter << Init->getSourceRange();
} else {
// Other initializers are fine.
return;
}
S.Diag(Member->getLocation(), diag::note_ref_or_ptr_member_declared_here)
<< (unsigned)IsPointer;
}
MemInitResult
Sema::BuildMemberInitializer(ValueDecl *Member, Expr *Init,
SourceLocation IdLoc) {
FieldDecl *DirectMember = dyn_cast<FieldDecl>(Member);
IndirectFieldDecl *IndirectMember = dyn_cast<IndirectFieldDecl>(Member);
assert((DirectMember || IndirectMember) &&
"Member must be a FieldDecl or IndirectFieldDecl");
if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
return true;
if (Member->isInvalidDecl())
return true;
MultiExprArg Args;
if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
} else if (InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) {
Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
} else {
// Template instantiation doesn't reconstruct ParenListExprs for us.
Args = Init;
}
SourceRange InitRange = Init->getSourceRange();
if (Member->getType()->isDependentType() || Init->isTypeDependent()) {
// Can't check initialization for a member of dependent type or when
// any of the arguments are type-dependent expressions.
DiscardCleanupsInEvaluationContext();
} else {
bool InitList = false;
if (isa<InitListExpr>(Init)) {
InitList = true;
Args = Init;
}
// Initialize the member.
InitializedEntity MemberEntity =
DirectMember ? InitializedEntity::InitializeMember(DirectMember, nullptr)
: InitializedEntity::InitializeMember(IndirectMember,
nullptr);
InitializationKind Kind =
InitList ? InitializationKind::CreateDirectList(IdLoc)
: InitializationKind::CreateDirect(IdLoc, InitRange.getBegin(),
InitRange.getEnd());
InitializationSequence InitSeq(*this, MemberEntity, Kind, Args);
ExprResult MemberInit = InitSeq.Perform(*this, MemberEntity, Kind, Args,
nullptr);
if (MemberInit.isInvalid())
return true;
CheckForDanglingReferenceOrPointer(*this, Member, MemberInit.get(), IdLoc);
// C++11 [class.base.init]p7:
// The initialization of each base and member constitutes a
// full-expression.
MemberInit = ActOnFinishFullExpr(MemberInit.get(), InitRange.getBegin());
if (MemberInit.isInvalid())
return true;
Init = MemberInit.get();
}
if (DirectMember) {
return new (Context) CXXCtorInitializer(Context, DirectMember, IdLoc,
InitRange.getBegin(), Init,
InitRange.getEnd());
} else {
return new (Context) CXXCtorInitializer(Context, IndirectMember, IdLoc,
InitRange.getBegin(), Init,
InitRange.getEnd());
}
}
MemInitResult
Sema::BuildDelegatingInitializer(TypeSourceInfo *TInfo, Expr *Init,
CXXRecordDecl *ClassDecl) {
SourceLocation NameLoc = TInfo->getTypeLoc().getLocalSourceRange().getBegin();
if (!LangOpts.CPlusPlus11)
return Diag(NameLoc, diag::err_delegating_ctor)
<< TInfo->getTypeLoc().getLocalSourceRange();
Diag(NameLoc, diag::warn_cxx98_compat_delegating_ctor);
bool InitList = true;
MultiExprArg Args = Init;
if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
InitList = false;
Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
}
SourceRange InitRange = Init->getSourceRange();
// Initialize the object.
InitializedEntity DelegationEntity = InitializedEntity::InitializeDelegation(
QualType(ClassDecl->getTypeForDecl(), 0));
InitializationKind Kind =
InitList ? InitializationKind::CreateDirectList(NameLoc)
: InitializationKind::CreateDirect(NameLoc, InitRange.getBegin(),
InitRange.getEnd());
InitializationSequence InitSeq(*this, DelegationEntity, Kind, Args);
ExprResult DelegationInit = InitSeq.Perform(*this, DelegationEntity, Kind,
Args, nullptr);
if (DelegationInit.isInvalid())
return true;
assert(cast<CXXConstructExpr>(DelegationInit.get())->getConstructor() &&
"Delegating constructor with no target?");
// C++11 [class.base.init]p7:
// The initialization of each base and member constitutes a
// full-expression.
DelegationInit = ActOnFinishFullExpr(DelegationInit.get(),
InitRange.getBegin());
if (DelegationInit.isInvalid())
return true;
// If we are in a dependent context, template instantiation will
// perform this type-checking again. Just save the arguments that we
// received in a ParenListExpr.
// FIXME: This isn't quite ideal, since our ASTs don't capture all
// of the information that we have about the base
// initializer. However, deconstructing the ASTs is a dicey process,
// and this approach is far more likely to get the corner cases right.
if (CurContext->isDependentContext())
DelegationInit = Init;
return new (Context) CXXCtorInitializer(Context, TInfo, InitRange.getBegin(),
DelegationInit.getAs<Expr>(),
InitRange.getEnd());
}
MemInitResult
Sema::BuildBaseInitializer(QualType BaseType, TypeSourceInfo *BaseTInfo,
Expr *Init, CXXRecordDecl *ClassDecl,
SourceLocation EllipsisLoc) {
SourceLocation BaseLoc
= BaseTInfo->getTypeLoc().getLocalSourceRange().getBegin();
if (!BaseType->isDependentType() && !BaseType->isRecordType())
return Diag(BaseLoc, diag::err_base_init_does_not_name_class)
<< BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
// C++ [class.base.init]p2:
// [...] Unless the mem-initializer-id names a nonstatic data
// member of the constructor's class or a direct or virtual base
// of that class, the mem-initializer is ill-formed. A
// mem-initializer-list can initialize a base class using any
// name that denotes that base class type.
bool Dependent = BaseType->isDependentType() || Init->isTypeDependent();
SourceRange InitRange = Init->getSourceRange();
if (EllipsisLoc.isValid()) {
// This is a pack expansion.
if (!BaseType->containsUnexpandedParameterPack()) {
Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
<< SourceRange(BaseLoc, InitRange.getEnd());
EllipsisLoc = SourceLocation();
}
} else {
// Check for any unexpanded parameter packs.
if (DiagnoseUnexpandedParameterPack(BaseLoc, BaseTInfo, UPPC_Initializer))
return true;
if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
return true;
}
// Check for direct and virtual base classes.
const CXXBaseSpecifier *DirectBaseSpec = nullptr;
const CXXBaseSpecifier *VirtualBaseSpec = nullptr;
if (!Dependent) {
if (Context.hasSameUnqualifiedType(QualType(ClassDecl->getTypeForDecl(),0),
BaseType))
return BuildDelegatingInitializer(BaseTInfo, Init, ClassDecl);
FindBaseInitializer(*this, ClassDecl, BaseType, DirectBaseSpec,
VirtualBaseSpec);
// C++ [base.class.init]p2:
// Unless the mem-initializer-id names a nonstatic data member of the
// constructor's class or a direct or virtual base of that class, the
// mem-initializer is ill-formed.
if (!DirectBaseSpec && !VirtualBaseSpec) {
// If the class has any dependent bases, then it's possible that
// one of those types will resolve to the same type as
// BaseType. Therefore, just treat this as a dependent base
// class initialization. FIXME: Should we try to check the
// initialization anyway? It seems odd.
if (ClassDecl->hasAnyDependentBases())
Dependent = true;
else
return Diag(BaseLoc, diag::err_not_direct_base_or_virtual)
<< BaseType << Context.getTypeDeclType(ClassDecl)
<< BaseTInfo->getTypeLoc().getLocalSourceRange();
}
}
if (Dependent) {
DiscardCleanupsInEvaluationContext();
return new (Context) CXXCtorInitializer(Context, BaseTInfo,
/*IsVirtual=*/false,
InitRange.getBegin(), Init,
InitRange.getEnd(), EllipsisLoc);
}
// C++ [base.class.init]p2:
// If a mem-initializer-id is ambiguous because it designates both
// a direct non-virtual base class and an inherited virtual base
// class, the mem-initializer is ill-formed.
if (DirectBaseSpec && VirtualBaseSpec)
return Diag(BaseLoc, diag::err_base_init_direct_and_virtual)
<< BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
const CXXBaseSpecifier *BaseSpec = DirectBaseSpec;
if (!BaseSpec)
BaseSpec = VirtualBaseSpec;
// Initialize the base.
bool InitList = true;
MultiExprArg Args = Init;
if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
InitList = false;
Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
}
InitializedEntity BaseEntity =
InitializedEntity::InitializeBase(Context, BaseSpec, VirtualBaseSpec);
InitializationKind Kind =
InitList ? InitializationKind::CreateDirectList(BaseLoc)
: InitializationKind::CreateDirect(BaseLoc, InitRange.getBegin(),
InitRange.getEnd());
InitializationSequence InitSeq(*this, BaseEntity, Kind, Args);
ExprResult BaseInit = InitSeq.Perform(*this, BaseEntity, Kind, Args, nullptr);
if (BaseInit.isInvalid())
return true;
// C++11 [class.base.init]p7:
// The initialization of each base and member constitutes a
// full-expression.
BaseInit = ActOnFinishFullExpr(BaseInit.get(), InitRange.getBegin());
if (BaseInit.isInvalid())
return true;
// If we are in a dependent context, template instantiation will
// perform this type-checking again. Just save the arguments that we
// received in a ParenListExpr.
// FIXME: This isn't quite ideal, since our ASTs don't capture all
// of the information that we have about the base
// initializer. However, deconstructing the ASTs is a dicey process,
// and this approach is far more likely to get the corner cases right.
if (CurContext->isDependentContext())
BaseInit = Init;
return new (Context) CXXCtorInitializer(Context, BaseTInfo,
BaseSpec->isVirtual(),
InitRange.getBegin(),
BaseInit.getAs<Expr>(),
InitRange.getEnd(), EllipsisLoc);
}
// Create a static_cast\<T&&>(expr).
static Expr *CastForMoving(Sema &SemaRef, Expr *E, QualType T = QualType()) {
if (T.isNull()) T = E->getType();
QualType TargetType = SemaRef.BuildReferenceType(
T, /*SpelledAsLValue*/false, SourceLocation(), DeclarationName());
SourceLocation ExprLoc = E->getLocStart();
TypeSourceInfo *TargetLoc = SemaRef.Context.getTrivialTypeSourceInfo(
TargetType, ExprLoc);
return SemaRef.BuildCXXNamedCast(ExprLoc, tok::kw_static_cast, TargetLoc, E,
SourceRange(ExprLoc, ExprLoc),
E->getSourceRange()).get();
}
/// ImplicitInitializerKind - How an implicit base or member initializer should
/// initialize its base or member.
enum ImplicitInitializerKind {
IIK_Default,
IIK_Copy,
IIK_Move,
IIK_Inherit
};
static bool
BuildImplicitBaseInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
ImplicitInitializerKind ImplicitInitKind,
CXXBaseSpecifier *BaseSpec,
bool IsInheritedVirtualBase,
CXXCtorInitializer *&CXXBaseInit) {
InitializedEntity InitEntity
= InitializedEntity::InitializeBase(SemaRef.Context, BaseSpec,
IsInheritedVirtualBase);
ExprResult BaseInit;
switch (ImplicitInitKind) {
case IIK_Inherit: {
const CXXRecordDecl *Inherited =
Constructor->getInheritedConstructor()->getParent();
const CXXRecordDecl *Base = BaseSpec->getType()->getAsCXXRecordDecl();
if (Base && Inherited->getCanonicalDecl() == Base->getCanonicalDecl()) {
// C++11 [class.inhctor]p8:
// Each expression in the expression-list is of the form
// static_cast<T&&>(p), where p is the name of the corresponding
// constructor parameter and T is the declared type of p.
SmallVector<Expr*, 16> Args;
for (unsigned I = 0, E = Constructor->getNumParams(); I != E; ++I) {
ParmVarDecl *PD = Constructor->getParamDecl(I);
ExprResult ArgExpr =
SemaRef.BuildDeclRefExpr(PD, PD->getType().getNonReferenceType(),
VK_LValue, SourceLocation());
if (ArgExpr.isInvalid())
return true;
Args.push_back(CastForMoving(SemaRef, ArgExpr.get(), PD->getType()));
}
InitializationKind InitKind = InitializationKind::CreateDirect(
Constructor->getLocation(), SourceLocation(), SourceLocation());
InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, Args);
BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, Args);
break;
}
}
// Fall through.
case IIK_Default: {
InitializationKind InitKind
= InitializationKind::CreateDefault(Constructor->getLocation());
InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
break;
}
case IIK_Move:
case IIK_Copy: {
bool Moving = ImplicitInitKind == IIK_Move;
ParmVarDecl *Param = Constructor->getParamDecl(0);
QualType ParamType = Param->getType().getNonReferenceType();
Expr *CopyCtorArg =
DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
SourceLocation(), Param, false,
Constructor->getLocation(), ParamType,
VK_LValue, nullptr);
SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(CopyCtorArg));
// Cast to the base class to avoid ambiguities.
QualType ArgTy =
SemaRef.Context.getQualifiedType(BaseSpec->getType().getUnqualifiedType(),
ParamType.getQualifiers());
if (Moving) {
CopyCtorArg = CastForMoving(SemaRef, CopyCtorArg);
}
CXXCastPath BasePath;
BasePath.push_back(BaseSpec);
CopyCtorArg = SemaRef.ImpCastExprToType(CopyCtorArg, ArgTy,
CK_UncheckedDerivedToBase,
Moving ? VK_XValue : VK_LValue,
&BasePath).get();
InitializationKind InitKind
= InitializationKind::CreateDirect(Constructor->getLocation(),
SourceLocation(), SourceLocation());
InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, CopyCtorArg);
BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, CopyCtorArg);
break;
}
}
BaseInit = SemaRef.MaybeCreateExprWithCleanups(BaseInit);
if (BaseInit.isInvalid())
return true;
CXXBaseInit =
new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
SemaRef.Context.getTrivialTypeSourceInfo(BaseSpec->getType(),
SourceLocation()),
BaseSpec->isVirtual(),
SourceLocation(),
BaseInit.getAs<Expr>(),
SourceLocation(),
SourceLocation());
return false;
}
static bool RefersToRValueRef(Expr *MemRef) {
ValueDecl *Referenced = cast<MemberExpr>(MemRef)->getMemberDecl();
return Referenced->getType()->isRValueReferenceType();
}
static bool
BuildImplicitMemberInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
ImplicitInitializerKind ImplicitInitKind,
FieldDecl *Field, IndirectFieldDecl *Indirect,
CXXCtorInitializer *&CXXMemberInit) {
if (Field->isInvalidDecl())
return true;
SourceLocation Loc = Constructor->getLocation();
if (ImplicitInitKind == IIK_Copy || ImplicitInitKind == IIK_Move) {
bool Moving = ImplicitInitKind == IIK_Move;
ParmVarDecl *Param = Constructor->getParamDecl(0);
QualType ParamType = Param->getType().getNonReferenceType();
// Suppress copying zero-width bitfields.
if (Field->isBitField() && Field->getBitWidthValue(SemaRef.Context) == 0)
return false;
Expr *MemberExprBase =
DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
SourceLocation(), Param, false,
Loc, ParamType, VK_LValue, nullptr);
SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(MemberExprBase));
if (Moving) {
MemberExprBase = CastForMoving(SemaRef, MemberExprBase);
}
// Build a reference to this field within the parameter.
CXXScopeSpec SS;
LookupResult MemberLookup(SemaRef, Field->getDeclName(), Loc,
Sema::LookupMemberName);
MemberLookup.addDecl(Indirect ? cast<ValueDecl>(Indirect)
: cast<ValueDecl>(Field), AS_public);
MemberLookup.resolveKind();
ExprResult CtorArg
= SemaRef.BuildMemberReferenceExpr(MemberExprBase,
ParamType, Loc,
/*IsArrow=*/false,
SS,
/*TemplateKWLoc=*/SourceLocation(),
/*FirstQualifierInScope=*/nullptr,
MemberLookup,
/*TemplateArgs=*/nullptr);
if (CtorArg.isInvalid())
return true;
// C++11 [class.copy]p15:
// - if a member m has rvalue reference type T&&, it is direct-initialized
// with static_cast<T&&>(x.m);
if (RefersToRValueRef(CtorArg.get())) {
CtorArg = CastForMoving(SemaRef, CtorArg.get());
}
// When the field we are copying is an array, create index variables for
// each dimension of the array. We use these index variables to subscript
// the source array, and other clients (e.g., CodeGen) will perform the
// necessary iteration with these index variables.
SmallVector<VarDecl *, 4> IndexVariables;
QualType BaseType = Field->getType();
QualType SizeType = SemaRef.Context.getSizeType();
bool InitializingArray = false;
while (const ConstantArrayType *Array
= SemaRef.Context.getAsConstantArrayType(BaseType)) {
InitializingArray = true;
// Create the iteration variable for this array index.
IdentifierInfo *IterationVarName = nullptr;
{
SmallString<8> Str;
llvm::raw_svector_ostream OS(Str);
OS << "__i" << IndexVariables.size();
IterationVarName = &SemaRef.Context.Idents.get(OS.str());
}
VarDecl *IterationVar
= VarDecl::Create(SemaRef.Context, SemaRef.CurContext, Loc, Loc,
IterationVarName, SizeType,
SemaRef.Context.getTrivialTypeSourceInfo(SizeType, Loc),
SC_None);
IndexVariables.push_back(IterationVar);
// Create a reference to the iteration variable.
ExprResult IterationVarRef
= SemaRef.BuildDeclRefExpr(IterationVar, SizeType, VK_LValue, Loc);
assert(!IterationVarRef.isInvalid() &&
"Reference to invented variable cannot fail!");
IterationVarRef = SemaRef.DefaultLvalueConversion(IterationVarRef.get());
assert(!IterationVarRef.isInvalid() &&
"Conversion of invented variable cannot fail!");
// Subscript the array with this iteration variable.
CtorArg = SemaRef.CreateBuiltinArraySubscriptExpr(CtorArg.get(), Loc,
IterationVarRef.get(),
Loc);
if (CtorArg.isInvalid())
return true;
BaseType = Array->getElementType();
}
// The array subscript expression is an lvalue, which is wrong for moving.
if (Moving && InitializingArray)
CtorArg = CastForMoving(SemaRef, CtorArg.get());
// Construct the entity that we will be initializing. For an array, this
// will be first element in the array, which may require several levels
// of array-subscript entities.
SmallVector<InitializedEntity, 4> Entities;
Entities.reserve(1 + IndexVariables.size());
if (Indirect)
Entities.push_back(InitializedEntity::InitializeMember(Indirect));
else
Entities.push_back(InitializedEntity::InitializeMember(Field));
for (unsigned I = 0, N = IndexVariables.size(); I != N; ++I)
Entities.push_back(InitializedEntity::InitializeElement(SemaRef.Context,
0,
Entities.back()));
// Direct-initialize to use the copy constructor.
InitializationKind InitKind =
InitializationKind::CreateDirect(Loc, SourceLocation(), SourceLocation());
Expr *CtorArgE = CtorArg.getAs<Expr>();
InitializationSequence InitSeq(SemaRef, Entities.back(), InitKind, CtorArgE);
ExprResult MemberInit
= InitSeq.Perform(SemaRef, Entities.back(), InitKind,
MultiExprArg(&CtorArgE, 1));
MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
if (MemberInit.isInvalid())
return true;
if (Indirect) {
assert(IndexVariables.size() == 0 &&
"Indirect field improperly initialized");
CXXMemberInit
= new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Indirect,
Loc, Loc,
MemberInit.getAs<Expr>(),
Loc);
} else
CXXMemberInit = CXXCtorInitializer::Create(SemaRef.Context, Field, Loc,
Loc, MemberInit.getAs<Expr>(),
Loc,
IndexVariables.data(),
IndexVariables.size());
return false;
}
assert((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) &&
"Unhandled implicit init kind!");
QualType FieldBaseElementType =
SemaRef.Context.getBaseElementType(Field->getType());
if (FieldBaseElementType->isRecordType()) {
InitializedEntity InitEntity
= Indirect? InitializedEntity::InitializeMember(Indirect)
: InitializedEntity::InitializeMember(Field);
InitializationKind InitKind =
InitializationKind::CreateDefault(Loc);
InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
ExprResult MemberInit =
InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
if (MemberInit.isInvalid())
return true;
if (Indirect)
CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
Indirect, Loc,
Loc,
MemberInit.get(),
Loc);
else
CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
Field, Loc, Loc,
MemberInit.get(),
Loc);
return false;
}
if (!Field->getParent()->isUnion()) {
if (FieldBaseElementType->isReferenceType()) {
SemaRef.Diag(Constructor->getLocation(),
diag::err_uninitialized_member_in_ctor)
<< (int)Constructor->isImplicit()
<< SemaRef.Context.getTagDeclType(Constructor->getParent())
<< 0 << Field->getDeclName();
SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
return true;
}
if (FieldBaseElementType.isConstQualified()) {
SemaRef.Diag(Constructor->getLocation(),
diag::err_uninitialized_member_in_ctor)
<< (int)Constructor->isImplicit()
<< SemaRef.Context.getTagDeclType(Constructor->getParent())
<< 1 << Field->getDeclName();
SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
return true;
}
}
if (SemaRef.getLangOpts().ObjCAutoRefCount &&
FieldBaseElementType->isObjCRetainableType() &&
FieldBaseElementType.getObjCLifetime() != Qualifiers::OCL_None &&
FieldBaseElementType.getObjCLifetime() != Qualifiers::OCL_ExplicitNone) {
// ARC:
// Default-initialize Objective-C pointers to NULL.
CXXMemberInit
= new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Field,
Loc, Loc,
new (SemaRef.Context) ImplicitValueInitExpr(Field->getType()),
Loc);
return false;
}
// Nothing to initialize.
CXXMemberInit = nullptr;
return false;
}
namespace {
struct BaseAndFieldInfo {
Sema &S;
CXXConstructorDecl *Ctor;
bool AnyErrorsInInits;
ImplicitInitializerKind IIK;
llvm::DenseMap<const void *, CXXCtorInitializer*> AllBaseFields;
SmallVector<CXXCtorInitializer*, 8> AllToInit;
llvm::DenseMap<TagDecl*, FieldDecl*> ActiveUnionMember;
BaseAndFieldInfo(Sema &S, CXXConstructorDecl *Ctor, bool ErrorsInInits)
: S(S), Ctor(Ctor), AnyErrorsInInits(ErrorsInInits) {
bool Generated = Ctor->isImplicit() || Ctor->isDefaulted();
if (Generated && Ctor->isCopyConstructor())
IIK = IIK_Copy;
else if (Generated && Ctor->isMoveConstructor())
IIK = IIK_Move;
else if (Ctor->getInheritedConstructor())
IIK = IIK_Inherit;
else
IIK = IIK_Default;
}
bool isImplicitCopyOrMove() const {
switch (IIK) {
case IIK_Copy:
case IIK_Move:
return true;
case IIK_Default:
case IIK_Inherit:
return false;
}
llvm_unreachable("Invalid ImplicitInitializerKind!");
}
bool addFieldInitializer(CXXCtorInitializer *Init) {
AllToInit.push_back(Init);
// Check whether this initializer makes the field "used".
if (Init->getInit()->HasSideEffects(S.Context))
S.UnusedPrivateFields.remove(Init->getAnyMember());
return false;
}
bool isInactiveUnionMember(FieldDecl *Field) {
RecordDecl *Record = Field->getParent();
if (!Record->isUnion())
return false;
if (FieldDecl *Active =
ActiveUnionMember.lookup(Record->getCanonicalDecl()))
return Active != Field->getCanonicalDecl();
// In an implicit copy or move constructor, ignore any in-class initializer.
if (isImplicitCopyOrMove())
return true;
// If there's no explicit initialization, the field is active only if it
// has an in-class initializer...
if (Field->hasInClassInitializer())
return false;
// ... or it's an anonymous struct or union whose class has an in-class
// initializer.
if (!Field->isAnonymousStructOrUnion())
return true;
CXXRecordDecl *FieldRD = Field->getType()->getAsCXXRecordDecl();
return !FieldRD->hasInClassInitializer();
}
/// \brief Determine whether the given field is, or is within, a union member
/// that is inactive (because there was an initializer given for a different
/// member of the union, or because the union was not initialized at all).
bool isWithinInactiveUnionMember(FieldDecl *Field,
IndirectFieldDecl *Indirect) {
if (!Indirect)
return isInactiveUnionMember(Field);
for (auto *C : Indirect->chain()) {
FieldDecl *Field = dyn_cast<FieldDecl>(C);
if (Field && isInactiveUnionMember(Field))
return true;
}
return false;
}
};
}
/// \brief Determine whether the given type is an incomplete or zero-lenfgth
/// array type.
static bool isIncompleteOrZeroLengthArrayType(ASTContext &Context, QualType T) {
if (T->isIncompleteArrayType())
return true;
while (const ConstantArrayType *ArrayT = Context.getAsConstantArrayType(T)) {
if (!ArrayT->getSize())
return true;
T = ArrayT->getElementType();
}
return false;
}
static bool CollectFieldInitializer(Sema &SemaRef, BaseAndFieldInfo &Info,
FieldDecl *Field,
IndirectFieldDecl *Indirect = nullptr) {
if (Field->isInvalidDecl())
return false;
// Overwhelmingly common case: we have a direct initializer for this field.
if (CXXCtorInitializer *Init =
Info.AllBaseFields.lookup(Field->getCanonicalDecl()))
return Info.addFieldInitializer(Init);
// C++11 [class.base.init]p8:
// if the entity is a non-static data member that has a
// brace-or-equal-initializer and either
// -- the constructor's class is a union and no other variant member of that
// union is designated by a mem-initializer-id or
// -- the constructor's class is not a union, and, if the entity is a member
// of an anonymous union, no other member of that union is designated by
// a mem-initializer-id,
// the entity is initialized as specified in [dcl.init].
//
// We also apply the same rules to handle anonymous structs within anonymous
// unions.
if (Info.isWithinInactiveUnionMember(Field, Indirect))
return false;
if (Field->hasInClassInitializer() && !Info.isImplicitCopyOrMove()) {
Expr *DIE = CXXDefaultInitExpr::Create(SemaRef.Context,
Info.Ctor->getLocation(), Field);
CXXCtorInitializer *Init;
if (Indirect)
Init = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Indirect,
SourceLocation(),
SourceLocation(), DIE,
SourceLocation());
else
Init = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Field,
SourceLocation(),
SourceLocation(), DIE,
SourceLocation());
return Info.addFieldInitializer(Init);
}
// Don't initialize incomplete or zero-length arrays.
if (isIncompleteOrZeroLengthArrayType(SemaRef.Context, Field->getType()))
return false;
// Don't try to build an implicit initializer if there were semantic
// errors in any of the initializers (and therefore we might be
// missing some that the user actually wrote).
if (Info.AnyErrorsInInits)
return false;
CXXCtorInitializer *Init = nullptr;
if (BuildImplicitMemberInitializer(Info.S, Info.Ctor, Info.IIK, Field,
Indirect, Init))
return true;
if (!Init)
return false;
return Info.addFieldInitializer(Init);
}
bool
Sema::SetDelegatingInitializer(CXXConstructorDecl *Constructor,
CXXCtorInitializer *Initializer) {
assert(Initializer->isDelegatingInitializer());
Constructor->setNumCtorInitializers(1);
CXXCtorInitializer **initializer =
new (Context) CXXCtorInitializer*[1];
memcpy(initializer, &Initializer, sizeof (CXXCtorInitializer*));
Constructor->setCtorInitializers(initializer);
if (CXXDestructorDecl *Dtor = LookupDestructor(Constructor->getParent())) {
MarkFunctionReferenced(Initializer->getSourceLocation(), Dtor);
DiagnoseUseOfDecl(Dtor, Initializer->getSourceLocation());
}
DelegatingCtorDecls.push_back(Constructor);
return false;
}
bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
ArrayRef<CXXCtorInitializer *> Initializers) {
if (Constructor->isDependentContext()) {
// Just store the initializers as written, they will be checked during
// instantiation.
if (!Initializers.empty()) {
Constructor->setNumCtorInitializers(Initializers.size());
CXXCtorInitializer **baseOrMemberInitializers =
new (Context) CXXCtorInitializer*[Initializers.size()];
memcpy(baseOrMemberInitializers, Initializers.data(),
Initializers.size() * sizeof(CXXCtorInitializer*));
Constructor->setCtorInitializers(baseOrMemberInitializers);
}
// Let template instantiation know whether we had errors.
if (AnyErrors)
Constructor->setInvalidDecl();
return false;
}
BaseAndFieldInfo Info(*this, Constructor, AnyErrors);
// We need to build the initializer AST according to order of construction
// and not what user specified in the Initializers list.
CXXRecordDecl *ClassDecl = Constructor->getParent()->getDefinition();
if (!ClassDecl)
return true;
bool HadError = false;
for (unsigned i = 0; i < Initializers.size(); i++) {
CXXCtorInitializer *Member = Initializers[i];
if (Member->isBaseInitializer())
Info.AllBaseFields[Member->getBaseClass()->getAs<RecordType>()] = Member;
else {
Info.AllBaseFields[Member->getAnyMember()->getCanonicalDecl()] = Member;
if (IndirectFieldDecl *F = Member->getIndirectMember()) {
for (auto *C : F->chain()) {
FieldDecl *FD = dyn_cast<FieldDecl>(C);
if (FD && FD->getParent()->isUnion())
Info.ActiveUnionMember.insert(std::make_pair(
FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
}
} else if (FieldDecl *FD = Member->getMember()) {
if (FD->getParent()->isUnion())
Info.ActiveUnionMember.insert(std::make_pair(
FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
}
}
}
// Keep track of the direct virtual bases.
llvm::SmallPtrSet<CXXBaseSpecifier *, 16> DirectVBases;
for (auto &I : ClassDecl->bases()) {
if (I.isVirtual())
DirectVBases.insert(&I);
}
// Push virtual bases before others.
for (auto &VBase : ClassDecl->vbases()) {
if (CXXCtorInitializer *Value
= Info.AllBaseFields.lookup(VBase.getType()->getAs<RecordType>())) {
// [class.base.init]p7, per DR257:
// A mem-initializer where the mem-initializer-id names a virtual base
// class is ignored during execution of a constructor of any class that
// is not the most derived class.
if (ClassDecl->isAbstract()) {
// FIXME: Provide a fixit to remove the base specifier. This requires
// tracking the location of the associated comma for a base specifier.
Diag(Value->getSourceLocation(), diag::warn_abstract_vbase_init_ignored)
<< VBase.getType() << ClassDecl;
DiagnoseAbstractType(ClassDecl);
}
Info.AllToInit.push_back(Value);
} else if (!AnyErrors && !ClassDecl->isAbstract()) {
// [class.base.init]p8, per DR257:
// If a given [...] base class is not named by a mem-initializer-id
// [...] and the entity is not a virtual base class of an abstract
// class, then [...] the entity is default-initialized.
bool IsInheritedVirtualBase = !DirectVBases.count(&VBase);
CXXCtorInitializer *CXXBaseInit;
if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
&VBase, IsInheritedVirtualBase,
CXXBaseInit)) {
HadError = true;
continue;
}
Info.AllToInit.push_back(CXXBaseInit);
}
}
// Non-virtual bases.
for (auto &Base : ClassDecl->bases()) {
// Virtuals are in the virtual base list and already constructed.
if (Base.isVirtual())
continue;
if (CXXCtorInitializer *Value
= Info.AllBaseFields.lookup(Base.getType()->getAs<RecordType>())) {
Info.AllToInit.push_back(Value);
} else if (!AnyErrors) {
CXXCtorInitializer *CXXBaseInit;
if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
&Base, /*IsInheritedVirtualBase=*/false,
CXXBaseInit)) {
HadError = true;
continue;
}
Info.AllToInit.push_back(CXXBaseInit);
}
}
// Fields.
for (auto *Mem : ClassDecl->decls()) {
if (auto *F = dyn_cast<FieldDecl>(Mem)) {
// C++ [class.bit]p2:
// A declaration for a bit-field that omits the identifier declares an
// unnamed bit-field. Unnamed bit-fields are not members and cannot be
// initialized.
if (F->isUnnamedBitfield())
continue;
// If we're not generating the implicit copy/move constructor, then we'll
// handle anonymous struct/union fields based on their individual
// indirect fields.
if (F->isAnonymousStructOrUnion() && !Info.isImplicitCopyOrMove())
continue;
if (CollectFieldInitializer(*this, Info, F))
HadError = true;
continue;
}
// Beyond this point, we only consider default initialization.
if (Info.isImplicitCopyOrMove())
continue;
if (auto *F = dyn_cast<IndirectFieldDecl>(Mem)) {
if (F->getType()->isIncompleteArrayType()) {
assert(ClassDecl->hasFlexibleArrayMember() &&
"Incomplete array type is not valid");
continue;
}
// Initialize each field of an anonymous struct individually.
if (CollectFieldInitializer(*this, Info, F->getAnonField(), F))
HadError = true;
continue;
}
}
unsigned NumInitializers = Info.AllToInit.size();
if (NumInitializers > 0) {
Constructor->setNumCtorInitializers(NumInitializers);
CXXCtorInitializer **baseOrMemberInitializers =
new (Context) CXXCtorInitializer*[NumInitializers];
memcpy(baseOrMemberInitializers, Info.AllToInit.data(),
NumInitializers * sizeof(CXXCtorInitializer*));
Constructor->setCtorInitializers(baseOrMemberInitializers);
// Constructors implicitly reference the base and member
// destructors.
MarkBaseAndMemberDestructorsReferenced(Constructor->getLocation(),
Constructor->getParent());
}
return HadError;
}
static void PopulateKeysForFields(FieldDecl *Field, SmallVectorImpl<const void*> &IdealInits) {
if (const RecordType *RT = Field->getType()->getAs<RecordType>()) {
const RecordDecl *RD = RT->getDecl();
if (RD->isAnonymousStructOrUnion()) {
for (auto *Field : RD->fields())
PopulateKeysForFields(Field, IdealInits);
return;
}
}
IdealInits.push_back(Field->getCanonicalDecl());
}
static const void *GetKeyForBase(ASTContext &Context, QualType BaseType) {
return Context.getCanonicalType(BaseType).getTypePtr();
}
static const void *GetKeyForMember(ASTContext &Context,
CXXCtorInitializer *Member) {
if (!Member->isAnyMemberInitializer())
return GetKeyForBase(Context, QualType(Member->getBaseClass(), 0));
return Member->getAnyMember()->getCanonicalDecl();
}
static void DiagnoseBaseOrMemInitializerOrder(
Sema &SemaRef, const CXXConstructorDecl *Constructor,
ArrayRef<CXXCtorInitializer *> Inits) {
if (Constructor->getDeclContext()->isDependentContext())
return;
// Don't check initializers order unless the warning is enabled at the
// location of at least one initializer.
bool ShouldCheckOrder = false;
for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
CXXCtorInitializer *Init = Inits[InitIndex];
if (!SemaRef.Diags.isIgnored(diag::warn_initializer_out_of_order,
Init->getSourceLocation())) {
ShouldCheckOrder = true;
break;
}
}
if (!ShouldCheckOrder)
return;
// Build the list of bases and members in the order that they'll
// actually be initialized. The explicit initializers should be in
// this same order but may be missing things.
SmallVector<const void*, 32> IdealInitKeys;
const CXXRecordDecl *ClassDecl = Constructor->getParent();
// 1. Virtual bases.
for (const auto &VBase : ClassDecl->vbases())
IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, VBase.getType()));
// 2. Non-virtual bases.
for (const auto &Base : ClassDecl->bases()) {
if (Base.isVirtual())
continue;
IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, Base.getType()));
}
// 3. Direct fields.
for (auto *Field : ClassDecl->fields()) {
if (Field->isUnnamedBitfield())
continue;
PopulateKeysForFields(Field, IdealInitKeys);
}
unsigned NumIdealInits = IdealInitKeys.size();
unsigned IdealIndex = 0;
CXXCtorInitializer *PrevInit = nullptr;
for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
CXXCtorInitializer *Init = Inits[InitIndex];
const void *InitKey = GetKeyForMember(SemaRef.Context, Init);
// Scan forward to try to find this initializer in the idealized
// initializers list.
for (; IdealIndex != NumIdealInits; ++IdealIndex)
if (InitKey == IdealInitKeys[IdealIndex])
break;
// If we didn't find this initializer, it must be because we
// scanned past it on a previous iteration. That can only
// happen if we're out of order; emit a warning.
if (IdealIndex == NumIdealInits && PrevInit) {
Sema::SemaDiagnosticBuilder D =
SemaRef.Diag(PrevInit->getSourceLocation(),
diag::warn_initializer_out_of_order);
if (PrevInit->isAnyMemberInitializer())
D << 0 << PrevInit->getAnyMember()->getDeclName();
else
D << 1 << PrevInit->getTypeSourceInfo()->getType();
if (Init->isAnyMemberInitializer())
D << 0 << Init->getAnyMember()->getDeclName();
else
D << 1 << Init->getTypeSourceInfo()->getType();
// Move back to the initializer's location in the ideal list.
for (IdealIndex = 0; IdealIndex != NumIdealInits; ++IdealIndex)
if (InitKey == IdealInitKeys[IdealIndex])
break;
assert(IdealIndex != NumIdealInits &&
"initializer not found in initializer list");
}
PrevInit = Init;
}
}
namespace {
bool CheckRedundantInit(Sema &S,
CXXCtorInitializer *Init,
CXXCtorInitializer *&PrevInit) {
if (!PrevInit) {
PrevInit = Init;
return false;
}
if (FieldDecl *Field = Init->getAnyMember())
S.Diag(Init->getSourceLocation(),
diag::err_multiple_mem_initialization)
<< Field->getDeclName()
<< Init->getSourceRange();
else {
const Type *BaseClass = Init->getBaseClass();
assert(BaseClass && "neither field nor base");
S.Diag(Init->getSourceLocation(),
diag::err_multiple_base_initialization)
<< QualType(BaseClass, 0)
<< Init->getSourceRange();
}
S.Diag(PrevInit->getSourceLocation(), diag::note_previous_initializer)
<< 0 << PrevInit->getSourceRange();
return true;
}
typedef std::pair<NamedDecl *, CXXCtorInitializer *> UnionEntry;
typedef llvm::DenseMap<RecordDecl*, UnionEntry> RedundantUnionMap;
bool CheckRedundantUnionInit(Sema &S,
CXXCtorInitializer *Init,
RedundantUnionMap &Unions) {
FieldDecl *Field = Init->getAnyMember();
RecordDecl *Parent = Field->getParent();
NamedDecl *Child = Field;
while (Parent->isAnonymousStructOrUnion() || Parent->isUnion()) {
if (Parent->isUnion()) {
UnionEntry &En = Unions[Parent];
if (En.first && En.first != Child) {
S.Diag(Init->getSourceLocation(),
diag::err_multiple_mem_union_initialization)
<< Field->getDeclName()
<< Init->getSourceRange();
S.Diag(En.second->getSourceLocation(), diag::note_previous_initializer)
<< 0 << En.second->getSourceRange();
return true;
}
if (!En.first) {
En.first = Child;
En.second = Init;
}
if (!Parent->isAnonymousStructOrUnion())
return false;
}
Child = Parent;
Parent = cast<RecordDecl>(Parent->getDeclContext());
}
return false;
}
}
/// ActOnMemInitializers - Handle the member initializers for a constructor.
void Sema::ActOnMemInitializers(Decl *ConstructorDecl,
SourceLocation ColonLoc,
ArrayRef<CXXCtorInitializer*> MemInits,
bool AnyErrors) {
if (!ConstructorDecl)
return;
AdjustDeclIfTemplate(ConstructorDecl);
CXXConstructorDecl *Constructor
= dyn_cast<CXXConstructorDecl>(ConstructorDecl);
if (!Constructor) {
Diag(ColonLoc, diag::err_only_constructors_take_base_inits);
return;
}
// Mapping for the duplicate initializers check.
// For member initializers, this is keyed with a FieldDecl*.
// For base initializers, this is keyed with a Type*.
llvm::DenseMap<const void *, CXXCtorInitializer *> Members;
// Mapping for the inconsistent anonymous-union initializers check.
RedundantUnionMap MemberUnions;
bool HadError = false;
for (unsigned i = 0; i < MemInits.size(); i++) {
CXXCtorInitializer *Init = MemInits[i];
// Set the source order index.
Init->setSourceOrder(i);
if (Init->isAnyMemberInitializer()) {
const void *Key = GetKeyForMember(Context, Init);
if (CheckRedundantInit(*this, Init, Members[Key]) ||
CheckRedundantUnionInit(*this, Init, MemberUnions))
HadError = true;
} else if (Init->isBaseInitializer()) {
const void *Key = GetKeyForMember(Context, Init);
if (CheckRedundantInit(*this, Init, Members[Key]))
HadError = true;
} else {
assert(Init->isDelegatingInitializer());
// This must be the only initializer
if (MemInits.size() != 1) {
Diag(Init->getSourceLocation(),
diag::err_delegating_initializer_alone)
<< Init->getSourceRange() << MemInits[i ? 0 : 1]->getSourceRange();
// We will treat this as being the only initializer.
}
SetDelegatingInitializer(Constructor, MemInits[i]);
// Return immediately as the initializer is set.
return;
}
}
if (HadError)
return;
DiagnoseBaseOrMemInitializerOrder(*this, Constructor, MemInits);
SetCtorInitializers(Constructor, AnyErrors, MemInits);
DiagnoseUninitializedFields(*this, Constructor);
}
void
Sema::MarkBaseAndMemberDestructorsReferenced(SourceLocation Location,
CXXRecordDecl *ClassDecl) {
// Ignore dependent contexts. Also ignore unions, since their members never
// have destructors implicitly called.
if (ClassDecl->isDependentContext() || ClassDecl->isUnion())
return;
// FIXME: all the access-control diagnostics are positioned on the
// field/base declaration. That's probably good; that said, the
// user might reasonably want to know why the destructor is being
// emitted, and we currently don't say.
// Non-static data members.
for (auto *Field : ClassDecl->fields()) {
if (Field->isInvalidDecl())
continue;
// Don't destroy incomplete or zero-length arrays.
if (isIncompleteOrZeroLengthArrayType(Context, Field->getType()))
continue;
QualType FieldType = Context.getBaseElementType(Field->getType());
const RecordType* RT = FieldType->getAs<RecordType>();
if (!RT)
continue;
CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
if (FieldClassDecl->isInvalidDecl())
continue;
if (FieldClassDecl->hasIrrelevantDestructor())
continue;
// The destructor for an implicit anonymous union member is never invoked.
if (FieldClassDecl->isUnion() && FieldClassDecl->isAnonymousStructOrUnion())
continue;
CXXDestructorDecl *Dtor = LookupDestructor(FieldClassDecl);
assert(Dtor && "No dtor found for FieldClassDecl!");
CheckDestructorAccess(Field->getLocation(), Dtor,
PDiag(diag::err_access_dtor_field)
<< Field->getDeclName()
<< FieldType);
MarkFunctionReferenced(Location, Dtor);
DiagnoseUseOfDecl(Dtor, Location);
}
llvm::SmallPtrSet<const RecordType *, 8> DirectVirtualBases;
// Bases.
for (const auto &Base : ClassDecl->bases()) {
// Bases are always records in a well-formed non-dependent class.
const RecordType *RT = Base.getType()->getAs<RecordType>();
// Remember direct virtual bases.
if (Base.isVirtual())
DirectVirtualBases.insert(RT);
CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
// If our base class is invalid, we probably can't get its dtor anyway.
if (BaseClassDecl->isInvalidDecl())
continue;
if (BaseClassDecl->hasIrrelevantDestructor())
continue;
CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
assert(Dtor && "No dtor found for BaseClassDecl!");
// FIXME: caret should be on the start of the class name
CheckDestructorAccess(Base.getLocStart(), Dtor,
PDiag(diag::err_access_dtor_base)
<< Base.getType()
<< Base.getSourceRange(),
Context.getTypeDeclType(ClassDecl));
MarkFunctionReferenced(Location, Dtor);
DiagnoseUseOfDecl(Dtor, Location);
}
// Virtual bases.
for (const auto &VBase : ClassDecl->vbases()) {
// Bases are always records in a well-formed non-dependent class.
const RecordType *RT = VBase.getType()->castAs<RecordType>();
// Ignore direct virtual bases.
if (DirectVirtualBases.count(RT))
continue;
CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
// If our base class is invalid, we probably can't get its dtor anyway.
if (BaseClassDecl->isInvalidDecl())
continue;
if (BaseClassDecl->hasIrrelevantDestructor())
continue;
CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
assert(Dtor && "No dtor found for BaseClassDecl!");
if (CheckDestructorAccess(
ClassDecl->getLocation(), Dtor,
PDiag(diag::err_access_dtor_vbase)
<< Context.getTypeDeclType(ClassDecl) << VBase.getType(),
Context.getTypeDeclType(ClassDecl)) ==
AR_accessible) {
CheckDerivedToBaseConversion(
Context.getTypeDeclType(ClassDecl), VBase.getType(),
diag::err_access_dtor_vbase, 0, ClassDecl->getLocation(),
SourceRange(), DeclarationName(), nullptr);
}
MarkFunctionReferenced(Location, Dtor);
DiagnoseUseOfDecl(Dtor, Location);
}
}
void Sema::ActOnDefaultCtorInitializers(Decl *CDtorDecl) {
if (!CDtorDecl)
return;
if (CXXConstructorDecl *Constructor
= dyn_cast<CXXConstructorDecl>(CDtorDecl)) {
SetCtorInitializers(Constructor, /*AnyErrors=*/false);
DiagnoseUninitializedFields(*this, Constructor);
}
}
bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T,
unsigned DiagID, AbstractDiagSelID SelID) {
class NonAbstractTypeDiagnoser : public TypeDiagnoser {
unsigned DiagID;
AbstractDiagSelID SelID;
public:
NonAbstractTypeDiagnoser(unsigned DiagID, AbstractDiagSelID SelID)
: TypeDiagnoser(DiagID == 0), DiagID(DiagID), SelID(SelID) { }
void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
if (Suppressed) return;
if (SelID == -1)
S.Diag(Loc, DiagID) << T;
else
S.Diag(Loc, DiagID) << SelID << T;
}
} Diagnoser(DiagID, SelID);
return RequireNonAbstractType(Loc, T, Diagnoser);
}
bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T,
TypeDiagnoser &Diagnoser) {
if (!getLangOpts().CPlusPlus)
return false;
if (const ArrayType *AT = Context.getAsArrayType(T))
return RequireNonAbstractType(Loc, AT->getElementType(), Diagnoser);
if (const PointerType *PT = T->getAs<PointerType>()) {
// Find the innermost pointer type.
while (const PointerType *T = PT->getPointeeType()->getAs<PointerType>())
PT = T;
if (const ArrayType *AT = Context.getAsArrayType(PT->getPointeeType()))
return RequireNonAbstractType(Loc, AT->getElementType(), Diagnoser);
}
const RecordType *RT = T->getAs<RecordType>();
if (!RT)
return false;
const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
// We can't answer whether something is abstract until it has a
// definition. If it's currently being defined, we'll walk back
// over all the declarations when we have a full definition.
const CXXRecordDecl *Def = RD->getDefinition();
if (!Def || Def->isBeingDefined())
return false;
if (!RD->isAbstract())
return false;
Diagnoser.diagnose(*this, Loc, T);
DiagnoseAbstractType(RD);
return true;
}
void Sema::DiagnoseAbstractType(const CXXRecordDecl *RD) {
// Check if we've already emitted the list of pure virtual functions
// for this class.
if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD))
return;
// If the diagnostic is suppressed, don't emit the notes. We're only
// going to emit them once, so try to attach them to a diagnostic we're
// actually going to show.
if (Diags.isLastDiagnosticIgnored())
return;
CXXFinalOverriderMap FinalOverriders;
RD->getFinalOverriders(FinalOverriders);
// Keep a set of seen pure methods so we won't diagnose the same method
// more than once.
llvm::SmallPtrSet<const CXXMethodDecl *, 8> SeenPureMethods;
for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
MEnd = FinalOverriders.end();
M != MEnd;
++M) {
for (OverridingMethods::iterator SO = M->second.begin(),
SOEnd = M->second.end();
SO != SOEnd; ++SO) {
// C++ [class.abstract]p4:
// A class is abstract if it contains or inherits at least one
// pure virtual function for which the final overrider is pure
// virtual.
//
if (SO->second.size() != 1)
continue;
if (!SO->second.front().Method->isPure())
continue;
if (!SeenPureMethods.insert(SO->second.front().Method))
continue;
Diag(SO->second.front().Method->getLocation(),
diag::note_pure_virtual_function)
<< SO->second.front().Method->getDeclName() << RD->getDeclName();
}
}
if (!PureVirtualClassDiagSet)
PureVirtualClassDiagSet.reset(new RecordDeclSetTy);
PureVirtualClassDiagSet->insert(RD);
}
namespace {
struct AbstractUsageInfo {
Sema &S;
CXXRecordDecl *Record;
CanQualType AbstractType;
bool Invalid;
AbstractUsageInfo(Sema &S, CXXRecordDecl *Record)
: S(S), Record(Record),
AbstractType(S.Context.getCanonicalType(
S.Context.getTypeDeclType(Record))),
Invalid(false) {}
void DiagnoseAbstractType() {
if (Invalid) return;
S.DiagnoseAbstractType(Record);
Invalid = true;
}
void CheckType(const NamedDecl *D, TypeLoc TL, Sema::AbstractDiagSelID Sel);
};
struct CheckAbstractUsage {
AbstractUsageInfo &Info;
const NamedDecl *Ctx;
CheckAbstractUsage(AbstractUsageInfo &Info, const NamedDecl *Ctx)
: Info(Info), Ctx(Ctx) {}
void Visit(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
switch (TL.getTypeLocClass()) {
#define ABSTRACT_TYPELOC(CLASS, PARENT)
#define TYPELOC(CLASS, PARENT) \
case TypeLoc::CLASS: Check(TL.castAs<CLASS##TypeLoc>(), Sel); break;
#include "clang/AST/TypeLocNodes.def"
}
}
void Check(FunctionProtoTypeLoc TL, Sema::AbstractDiagSelID Sel) {
Visit(TL.getReturnLoc(), Sema::AbstractReturnType);
for (unsigned I = 0, E = TL.getNumParams(); I != E; ++I) {
if (!TL.getParam(I))
continue;
TypeSourceInfo *TSI = TL.getParam(I)->getTypeSourceInfo();
if (TSI) Visit(TSI->getTypeLoc(), Sema::AbstractParamType);
}
}
void Check(ArrayTypeLoc TL, Sema::AbstractDiagSelID Sel) {
Visit(TL.getElementLoc(), Sema::AbstractArrayType);
}
void Check(TemplateSpecializationTypeLoc TL, Sema::AbstractDiagSelID Sel) {
// Visit the type parameters from a permissive context.
for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) {
TemplateArgumentLoc TAL = TL.getArgLoc(I);
if (TAL.getArgument().getKind() == TemplateArgument::Type)
if (TypeSourceInfo *TSI = TAL.getTypeSourceInfo())
Visit(TSI->getTypeLoc(), Sema::AbstractNone);
// TODO: other template argument types?
}
}
// Visit pointee types from a permissive context.
#define CheckPolymorphic(Type) \
void Check(Type TL, Sema::AbstractDiagSelID Sel) { \
Visit(TL.getNextTypeLoc(), Sema::AbstractNone); \
}
CheckPolymorphic(PointerTypeLoc)
CheckPolymorphic(ReferenceTypeLoc)
CheckPolymorphic(MemberPointerTypeLoc)
CheckPolymorphic(BlockPointerTypeLoc)
CheckPolymorphic(AtomicTypeLoc)
/// Handle all the types we haven't given a more specific
/// implementation for above.
void Check(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
// Every other kind of type that we haven't called out already
// that has an inner type is either (1) sugar or (2) contains that
// inner type in some way as a subobject.
if (TypeLoc Next = TL.getNextTypeLoc())
return Visit(Next, Sel);
// If there's no inner type and we're in a permissive context,
// don't diagnose.
if (Sel == Sema::AbstractNone) return;
// Check whether the type matches the abstract type.
QualType T = TL.getType();
if (T->isArrayType()) {
Sel = Sema::AbstractArrayType;
T = Info.S.Context.getBaseElementType(T);
}
CanQualType CT = T->getCanonicalTypeUnqualified().getUnqualifiedType();
if (CT != Info.AbstractType) return;
// It matched; do some magic.
if (Sel == Sema::AbstractArrayType) {
Info.S.Diag(Ctx->getLocation(), diag::err_array_of_abstract_type)
<< T << TL.getSourceRange();
} else {
Info.S.Diag(Ctx->getLocation(), diag::err_abstract_type_in_decl)
<< Sel << T << TL.getSourceRange();
}
Info.DiagnoseAbstractType();
}
};
void AbstractUsageInfo::CheckType(const NamedDecl *D, TypeLoc TL,
Sema::AbstractDiagSelID Sel) {
CheckAbstractUsage(*this, D).Visit(TL, Sel);
}
}
/// Check for invalid uses of an abstract type in a method declaration.
static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
CXXMethodDecl *MD) {
// No need to do the check on definitions, which require that
// the return/param types be complete.
if (MD->doesThisDeclarationHaveABody())
return;
// For safety's sake, just ignore it if we don't have type source
// information. This should never happen for non-implicit methods,
// but...
if (TypeSourceInfo *TSI = MD->getTypeSourceInfo())
Info.CheckType(MD, TSI->getTypeLoc(), Sema::AbstractNone);
}
/// Check for invalid uses of an abstract type within a class definition.
static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
CXXRecordDecl *RD) {
for (auto *D : RD->decls()) {
if (D->isImplicit()) continue;
// Methods and method templates.
if (isa<CXXMethodDecl>(D)) {
CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(D));
} else if (isa<FunctionTemplateDecl>(D)) {
FunctionDecl *FD = cast<FunctionTemplateDecl>(D)->getTemplatedDecl();
CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(FD));
// Fields and static variables.
} else if (isa<FieldDecl>(D)) {
FieldDecl *FD = cast<FieldDecl>(D);
if (TypeSourceInfo *TSI = FD->getTypeSourceInfo())
Info.CheckType(FD, TSI->getTypeLoc(), Sema::AbstractFieldType);
} else if (isa<VarDecl>(D)) {
VarDecl *VD = cast<VarDecl>(D);
if (TypeSourceInfo *TSI = VD->getTypeSourceInfo())
Info.CheckType(VD, TSI->getTypeLoc(), Sema::AbstractVariableType);
// Nested classes and class templates.
} else if (isa<CXXRecordDecl>(D)) {
CheckAbstractClassUsage(Info, cast<CXXRecordDecl>(D));
} else if (isa<ClassTemplateDecl>(D)) {
CheckAbstractClassUsage(Info,
cast<ClassTemplateDecl>(D)->getTemplatedDecl());
}
}
}
/// \brief Check class-level dllimport/dllexport attribute.
static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
Attr *ClassAttr = getDLLAttr(Class);
if (!ClassAttr)
return;
bool ClassExported = ClassAttr->getKind() == attr::DLLExport;
// Force declaration of implicit members so they can inherit the attribute.
S.ForceDeclarationOfImplicitMembers(Class);
// FIXME: MSVC's docs say all bases must be exportable, but this doesn't
// seem to be true in practice?
for (Decl *Member : Class->decls()) {
VarDecl *VD = dyn_cast<VarDecl>(Member);
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member);
// Only methods and static fields inherit the attributes.
if (!VD && !MD)
continue;
// Don't process deleted methods.
if (MD && MD->isDeleted())
continue;
if (MD && MD->isMoveAssignmentOperator() && !ClassExported &&
MD->isInlined()) {
// Current MSVC versions don't export the move assignment operators, so
// don't attempt to import them if we have a definition.
continue;
}
if (InheritableAttr *MemberAttr = getDLLAttr(Member)) {
if (S.Context.getTargetInfo().getCXXABI().isMicrosoft() &&
!MemberAttr->isInherited() && !ClassAttr->isInherited()) {
S.Diag(MemberAttr->getLocation(),
diag::err_attribute_dll_member_of_dll_class)
<< MemberAttr << ClassAttr;
S.Diag(ClassAttr->getLocation(), diag::note_previous_attribute);
Member->setInvalidDecl();
continue;
}
} else {
auto *NewAttr =
cast<InheritableAttr>(ClassAttr->clone(S.getASTContext()));
NewAttr->setInherited(true);
Member->addAttr(NewAttr);
}
if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member)) {
if (ClassExported) {
if (MD->isUserProvided()) {
// Instantiate non-default methods.
S.MarkFunctionReferenced(Class->getLocation(), MD);
} else if (!MD->isTrivial() || MD->isExplicitlyDefaulted() ||
MD->isCopyAssignmentOperator() ||
MD->isMoveAssignmentOperator()) {
// Instantiate non-trivial or explicitly defaulted methods, and the
// copy assignment / move assignment operators.
S.MarkFunctionReferenced(Class->getLocation(), MD);
// Resolve its exception specification; CodeGen needs it.
auto *FPT = MD->getType()->getAs<FunctionProtoType>();
S.ResolveExceptionSpec(Class->getLocation(), FPT);
S.ActOnFinishInlineMethodDef(MD);
}
}
}
}
}
/// \brief Perform semantic checks on a class definition that has been
/// completing, introducing implicitly-declared members, checking for
/// abstract types, etc.
void Sema::CheckCompletedCXXClass(CXXRecordDecl *Record) {
if (!Record)
return;
if (Record->isAbstract() && !Record->isInvalidDecl()) {
AbstractUsageInfo Info(*this, Record);
CheckAbstractClassUsage(Info, Record);
}
// If this is not an aggregate type and has no user-declared constructor,
// complain about any non-static data members of reference or const scalar
// type, since they will never get initializers.
if (!Record->isInvalidDecl() && !Record->isDependentType() &&
!Record->isAggregate() && !Record->hasUserDeclaredConstructor() &&
!Record->isLambda()) {
bool Complained = false;
for (const auto *F : Record->fields()) {
if (F->hasInClassInitializer() || F->isUnnamedBitfield())
continue;
if (F->getType()->isReferenceType() ||
(F->getType().isConstQualified() && F->getType()->isScalarType())) {
if (!Complained) {
Diag(Record->getLocation(), diag::warn_no_constructor_for_refconst)
<< Record->getTagKind() << Record;
Complained = true;
}
Diag(F->getLocation(), diag::note_refconst_member_not_initialized)
<< F->getType()->isReferenceType()
<< F->getDeclName();
}
}
}
if (Record->isDynamicClass() && !Record->isDependentType())
DynamicClasses.push_back(Record);
if (Record->getIdentifier()) {
// C++ [class.mem]p13:
// If T is the name of a class, then each of the following shall have a
// name different from T:
// - every member of every anonymous union that is a member of class T.
//
// C++ [class.mem]p14:
// In addition, if class T has a user-declared constructor (12.1), every
// non-static data member of class T shall have a name different from T.
DeclContext::lookup_result R = Record->lookup(Record->getDeclName());
for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E;
++I) {
NamedDecl *D = *I;
if ((isa<FieldDecl>(D) && Record->hasUserDeclaredConstructor()) ||
isa<IndirectFieldDecl>(D)) {
Diag(D->getLocation(), diag::err_member_name_of_class)
<< D->getDeclName();
break;
}
}
}
// Warn if the class has virtual methods but non-virtual public destructor.
if (Record->isPolymorphic() && !Record->isDependentType()) {
CXXDestructorDecl *dtor = Record->getDestructor();
if ((!dtor || (!dtor->isVirtual() && dtor->getAccess() == AS_public)) &&
!Record->hasAttr<FinalAttr>())
Diag(dtor ? dtor->getLocation() : Record->getLocation(),
diag::warn_non_virtual_dtor) << Context.getRecordType(Record);
}
if (Record->isAbstract()) {
if (FinalAttr *FA = Record->getAttr<FinalAttr>()) {
Diag(Record->getLocation(), diag::warn_abstract_final_class)
<< FA->isSpelledAsSealed();
DiagnoseAbstractType(Record);
}
}
if (!Record->isDependentType()) {
for (auto *M : Record->methods()) {
// See if a method overloads virtual methods in a base
// class without overriding any.
if (!M->isStatic())
DiagnoseHiddenVirtualMethods(M);
// Check whether the explicitly-defaulted special members are valid.
if (!M->isInvalidDecl() && M->isExplicitlyDefaulted())
CheckExplicitlyDefaultedSpecialMember(M);
// For an explicitly defaulted or deleted special member, we defer
// determining triviality until the class is complete. That time is now!
if (!M->isImplicit() && !M->isUserProvided()) {
CXXSpecialMember CSM = getSpecialMember(M);
if (CSM != CXXInvalid) {
M->setTrivial(SpecialMemberIsTrivial(M, CSM));
// Inform the class that we've finished declaring this member.
Record->finishedDefaultedOrDeletedMember(M);
}
}
}
}
// C++11 [dcl.constexpr]p8: A constexpr specifier for a non-static member
// function that is not a constructor declares that member function to be
// const. [...] The class of which that function is a member shall be
// a literal type.
//
// If the class has virtual bases, any constexpr members will already have
// been diagnosed by the checks performed on the member declaration, so
// suppress this (less useful) diagnostic.
//
// We delay this until we know whether an explicitly-defaulted (or deleted)
// destructor for the class is trivial.
if (LangOpts.CPlusPlus11 && !Record->isDependentType() &&
!Record->isLiteral() && !Record->getNumVBases()) {
for (const auto *M : Record->methods()) {
if (M->isConstexpr() && M->isInstance() && !isa<CXXConstructorDecl>(M)) {
switch (Record->getTemplateSpecializationKind()) {
case TSK_ImplicitInstantiation:
case TSK_ExplicitInstantiationDeclaration:
case TSK_ExplicitInstantiationDefinition:
// If a template instantiates to a non-literal type, but its members
// instantiate to constexpr functions, the template is technically
// ill-formed, but we allow it for sanity.
continue;
case TSK_Undeclared:
case TSK_ExplicitSpecialization:
RequireLiteralType(M->getLocation(), Context.getRecordType(Record),
diag::err_constexpr_method_non_literal);
break;
}
// Only produce one error per class.
break;
}
}
}
// ms_struct is a request to use the same ABI rules as MSVC. Check
// whether this class uses any C++ features that are implemented
// completely differently in MSVC, and if so, emit a diagnostic.
// That diagnostic defaults to an error, but we allow projects to
// map it down to a warning (or ignore it). It's a fairly common
// practice among users of the ms_struct pragma to mass-annotate
// headers, sweeping up a bunch of types that the project doesn't
// really rely on MSVC-compatible layout for. We must therefore
// support "ms_struct except for C++ stuff" as a secondary ABI.
if (Record->isMsStruct(Context) &&
(Record->isPolymorphic() || Record->getNumBases())) {
Diag(Record->getLocation(), diag::warn_cxx_ms_struct);
}
// Declare inheriting constructors. We do this eagerly here because:
// - The standard requires an eager diagnostic for conflicting inheriting
// constructors from different classes.
// - The lazy declaration of the other implicit constructors is so as to not
// waste space and performance on classes that are not meant to be
// instantiated (e.g. meta-functions). This doesn't apply to classes that
// have inheriting constructors.
DeclareInheritingConstructors(Record);
checkDLLAttribute(*this, Record);
}
/// Look up the special member function that would be called by a special
/// member function for a subobject of class type.
///
/// \param Class The class type of the subobject.
/// \param CSM The kind of special member function.
/// \param FieldQuals If the subobject is a field, its cv-qualifiers.
/// \param ConstRHS True if this is a copy operation with a const object
/// on its RHS, that is, if the argument to the outer special member
/// function is 'const' and this is not a field marked 'mutable'.
static Sema::SpecialMemberOverloadResult *lookupCallFromSpecialMember(
Sema &S, CXXRecordDecl *Class, Sema::CXXSpecialMember CSM,
unsigned FieldQuals, bool ConstRHS) {
unsigned LHSQuals = 0;
if (CSM == Sema::CXXCopyAssignment || CSM == Sema::CXXMoveAssignment)
LHSQuals = FieldQuals;
unsigned RHSQuals = FieldQuals;
if (CSM == Sema::CXXDefaultConstructor || CSM == Sema::CXXDestructor)
RHSQuals = 0;
else if (ConstRHS)
RHSQuals |= Qualifiers::Const;
return S.LookupSpecialMember(Class, CSM,
RHSQuals & Qualifiers::Const,
RHSQuals & Qualifiers::Volatile,
false,
LHSQuals & Qualifiers::Const,
LHSQuals & Qualifiers::Volatile);
}
/// Is the special member function which would be selected to perform the
/// specified operation on the specified class type a constexpr constructor?
static bool specialMemberIsConstexpr(Sema &S, CXXRecordDecl *ClassDecl,
Sema::CXXSpecialMember CSM,
unsigned Quals, bool ConstRHS) {
Sema::SpecialMemberOverloadResult *SMOR =
lookupCallFromSpecialMember(S, ClassDecl, CSM, Quals, ConstRHS);
if (!SMOR || !SMOR->getMethod())
// A constructor we wouldn't select can't be "involved in initializing"
// anything.
return true;
return SMOR->getMethod()->isConstexpr();
}
/// Determine whether the specified special member function would be constexpr
/// if it were implicitly defined.
static bool defaultedSpecialMemberIsConstexpr(Sema &S, CXXRecordDecl *ClassDecl,
Sema::CXXSpecialMember CSM,
bool ConstArg) {
if (!S.getLangOpts().CPlusPlus11)
return false;
// C++11 [dcl.constexpr]p4:
// In the definition of a constexpr constructor [...]
bool Ctor = true;
switch (CSM) {
case Sema::CXXDefaultConstructor:
// Since default constructor lookup is essentially trivial (and cannot
// involve, for instance, template instantiation), we compute whether a
// defaulted default constructor is constexpr directly within CXXRecordDecl.
//
// This is important for performance; we need to know whether the default
// constructor is constexpr to determine whether the type is a literal type.
return ClassDecl->defaultedDefaultConstructorIsConstexpr();
case Sema::CXXCopyConstructor:
case Sema::CXXMoveConstructor:
// For copy or move constructors, we need to perform overload resolution.
break;
case Sema::CXXCopyAssignment:
case Sema::CXXMoveAssignment:
if (!S.getLangOpts().CPlusPlus1y)
return false;
// In C++1y, we need to perform overload resolution.
Ctor = false;
break;
case Sema::CXXDestructor:
case Sema::CXXInvalid:
return false;
}
// -- if the class is a non-empty union, or for each non-empty anonymous
// union member of a non-union class, exactly one non-static data member
// shall be initialized; [DR1359]
//
// If we squint, this is guaranteed, since exactly one non-static data member
// will be initialized (if the constructor isn't deleted), we just don't know
// which one.
if (Ctor && ClassDecl->isUnion())
return true;
// -- the class shall not have any virtual base classes;
if (Ctor && ClassDecl->getNumVBases())
return false;
// C++1y [class.copy]p26:
// -- [the class] is a literal type, and
if (!Ctor && !ClassDecl->isLiteral())
return false;
// -- every constructor involved in initializing [...] base class
// sub-objects shall be a constexpr constructor;
// -- the assignment operator selected to copy/move each direct base
// class is a constexpr function, and
for (const auto &B : ClassDecl->bases()) {
const RecordType *BaseType = B.getType()->getAs<RecordType>();
if (!BaseType) continue;
CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
if (!specialMemberIsConstexpr(S, BaseClassDecl, CSM, 0, ConstArg))
return false;
}
// -- every constructor involved in initializing non-static data members
// [...] shall be a constexpr constructor;
// -- every non-static data member and base class sub-object shall be
// initialized
// -- for each non-static data member of X that is of class type (or array
// thereof), the assignment operator selected to copy/move that member is
// a constexpr function
for (const auto *F : ClassDecl->fields()) {
if (F->isInvalidDecl())
continue;
QualType BaseType = S.Context.getBaseElementType(F->getType());
if (const RecordType *RecordTy = BaseType->getAs<RecordType>()) {
CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
if (!specialMemberIsConstexpr(S, FieldRecDecl, CSM,
BaseType.getCVRQualifiers(),
ConstArg && !F->isMutable()))
return false;
}
}
// All OK, it's constexpr!
return true;
}
static Sema::ImplicitExceptionSpecification
computeImplicitExceptionSpec(Sema &S, SourceLocation Loc, CXXMethodDecl *MD) {
switch (S.getSpecialMember(MD)) {
case Sema::CXXDefaultConstructor:
return S.ComputeDefaultedDefaultCtorExceptionSpec(Loc, MD);
case Sema::CXXCopyConstructor:
return S.ComputeDefaultedCopyCtorExceptionSpec(MD);
case Sema::CXXCopyAssignment:
return S.ComputeDefaultedCopyAssignmentExceptionSpec(MD);
case Sema::CXXMoveConstructor:
return S.ComputeDefaultedMoveCtorExceptionSpec(MD);
case Sema::CXXMoveAssignment:
return S.ComputeDefaultedMoveAssignmentExceptionSpec(MD);
case Sema::CXXDestructor:
return S.ComputeDefaultedDtorExceptionSpec(MD);
case Sema::CXXInvalid:
break;
}
assert(cast<CXXConstructorDecl>(MD)->getInheritedConstructor() &&
"only special members have implicit exception specs");
return S.ComputeInheritingCtorExceptionSpec(cast<CXXConstructorDecl>(MD));
}
static FunctionProtoType::ExtProtoInfo getImplicitMethodEPI(Sema &S,
CXXMethodDecl *MD) {
FunctionProtoType::ExtProtoInfo EPI;
// Build an exception specification pointing back at this member.
EPI.ExceptionSpecType = EST_Unevaluated;
EPI.ExceptionSpecDecl = MD;
// Set the calling convention to the default for C++ instance methods.
EPI.ExtInfo = EPI.ExtInfo.withCallingConv(
S.Context.getDefaultCallingConvention(/*IsVariadic=*/false,
/*IsCXXMethod=*/true));
return EPI;
}
void Sema::EvaluateImplicitExceptionSpec(SourceLocation Loc, CXXMethodDecl *MD) {
const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
if (FPT->getExceptionSpecType() != EST_Unevaluated)
return;
// Evaluate the exception specification.
ImplicitExceptionSpecification ExceptSpec =
computeImplicitExceptionSpec(*this, Loc, MD);
FunctionProtoType::ExtProtoInfo EPI;
ExceptSpec.getEPI(EPI);
// Update the type of the special member to use it.
UpdateExceptionSpec(MD, EPI);
// A user-provided destructor can be defined outside the class. When that
// happens, be sure to update the exception specification on both
// declarations.
const FunctionProtoType *CanonicalFPT =
MD->getCanonicalDecl()->getType()->castAs<FunctionProtoType>();
if (CanonicalFPT->getExceptionSpecType() == EST_Unevaluated)
UpdateExceptionSpec(MD->getCanonicalDecl(), EPI);
}
void Sema::CheckExplicitlyDefaultedSpecialMember(CXXMethodDecl *MD) {
CXXRecordDecl *RD = MD->getParent();
CXXSpecialMember CSM = getSpecialMember(MD);
assert(MD->isExplicitlyDefaulted() && CSM != CXXInvalid &&
"not an explicitly-defaulted special member");
// Whether this was the first-declared instance of the constructor.
// This affects whether we implicitly add an exception spec and constexpr.
bool First = MD == MD->getCanonicalDecl();
bool HadError = false;
// C++11 [dcl.fct.def.default]p1:
// A function that is explicitly defaulted shall
// -- be a special member function (checked elsewhere),
// -- have the same type (except for ref-qualifiers, and except that a
// copy operation can take a non-const reference) as an implicit
// declaration, and
// -- not have default arguments.
unsigned ExpectedParams = 1;
if (CSM == CXXDefaultConstructor || CSM == CXXDestructor)
ExpectedParams = 0;
if (MD->getNumParams() != ExpectedParams) {
// This also checks for default arguments: a copy or move constructor with a
// default argument is classified as a default constructor, and assignment
// operations and destructors can't have default arguments.
Diag(MD->getLocation(), diag::err_defaulted_special_member_params)
<< CSM << MD->getSourceRange();
HadError = true;
} else if (MD->isVariadic()) {
Diag(MD->getLocation(), diag::err_defaulted_special_member_variadic)
<< CSM << MD->getSourceRange();
HadError = true;
}
const FunctionProtoType *Type = MD->getType()->getAs<FunctionProtoType>();
bool CanHaveConstParam = false;
if (CSM == CXXCopyConstructor)
CanHaveConstParam = RD->implicitCopyConstructorHasConstParam();
else if (CSM == CXXCopyAssignment)
CanHaveConstParam = RD->implicitCopyAssignmentHasConstParam();
QualType ReturnType = Context.VoidTy;
if (CSM == CXXCopyAssignment || CSM == CXXMoveAssignment) {
// Check for return type matching.
ReturnType = Type->getReturnType();
QualType ExpectedReturnType =
Context.getLValueReferenceType(Context.getTypeDeclType(RD));
if (!Context.hasSameType(ReturnType, ExpectedReturnType)) {
Diag(MD->getLocation(), diag::err_defaulted_special_member_return_type)
<< (CSM == CXXMoveAssignment) << ExpectedReturnType;
HadError = true;
}
// A defaulted special member cannot have cv-qualifiers.
if (Type->getTypeQuals()) {
Diag(MD->getLocation(), diag::err_defaulted_special_member_quals)
<< (CSM == CXXMoveAssignment) << getLangOpts().CPlusPlus1y;
HadError = true;
}
}
// Check for parameter type matching.
QualType ArgType = ExpectedParams ? Type->getParamType(0) : QualType();
bool HasConstParam = false;
if (ExpectedParams && ArgType->isReferenceType()) {
// Argument must be reference to possibly-const T.
QualType ReferentType = ArgType->getPointeeType();
HasConstParam = ReferentType.isConstQualified();
if (ReferentType.isVolatileQualified()) {
Diag(MD->getLocation(),
diag::err_defaulted_special_member_volatile_param) << CSM;
HadError = true;
}
if (HasConstParam && !CanHaveConstParam) {
if (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment) {
Diag(MD->getLocation(),
diag::err_defaulted_special_member_copy_const_param)
<< (CSM == CXXCopyAssignment);
// FIXME: Explain why this special member can't be const.
} else {
Diag(MD->getLocation(),
diag::err_defaulted_special_member_move_const_param)
<< (CSM == CXXMoveAssignment);
}
HadError = true;
}
} else if (ExpectedParams) {
// A copy assignment operator can take its argument by value, but a
// defaulted one cannot.
assert(CSM == CXXCopyAssignment && "unexpected non-ref argument");
Diag(MD->getLocation(), diag::err_defaulted_copy_assign_not_ref);
HadError = true;
}
// C++11 [dcl.fct.def.default]p2:
// An explicitly-defaulted function may be declared constexpr only if it
// would have been implicitly declared as constexpr,
// Do not apply this rule to members of class templates, since core issue 1358
// makes such functions always instantiate to constexpr functions. For
// functions which cannot be constexpr (for non-constructors in C++11 and for
// destructors in C++1y), this is checked elsewhere.
bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, RD, CSM,
HasConstParam);
if ((getLangOpts().CPlusPlus1y ? !isa<CXXDestructorDecl>(MD)
: isa<CXXConstructorDecl>(MD)) &&
MD->isConstexpr() && !Constexpr &&
MD->getTemplatedKind() == FunctionDecl::TK_NonTemplate) {
Diag(MD->getLocStart(), diag::err_incorrect_defaulted_constexpr) << CSM;
// FIXME: Explain why the special member can't be constexpr.
HadError = true;
}
// and may have an explicit exception-specification only if it is compatible
// with the exception-specification on the implicit declaration.
if (Type->hasExceptionSpec()) {
// Delay the check if this is the first declaration of the special member,
// since we may not have parsed some necessary in-class initializers yet.
if (First) {
// If the exception specification needs to be instantiated, do so now,
// before we clobber it with an EST_Unevaluated specification below.
if (Type->getExceptionSpecType() == EST_Uninstantiated) {
InstantiateExceptionSpec(MD->getLocStart(), MD);
Type = MD->getType()->getAs<FunctionProtoType>();
}
DelayedDefaultedMemberExceptionSpecs.push_back(std::make_pair(MD, Type));
} else
CheckExplicitlyDefaultedMemberExceptionSpec(MD, Type);
}
// If a function is explicitly defaulted on its first declaration,
if (First) {
// -- it is implicitly considered to be constexpr if the implicit
// definition would be,
MD->setConstexpr(Constexpr);
// -- it is implicitly considered to have the same exception-specification
// as if it had been implicitly declared,
FunctionProtoType::ExtProtoInfo EPI = Type->getExtProtoInfo();
EPI.ExceptionSpecType = EST_Unevaluated;
EPI.ExceptionSpecDecl = MD;
MD->setType(Context.getFunctionType(ReturnType,
ArrayRef<QualType>(&ArgType,
ExpectedParams),
EPI));
}
if (ShouldDeleteSpecialMember(MD, CSM)) {
if (First) {
SetDeclDeleted(MD, MD->getLocation());
} else {
// C++11 [dcl.fct.def.default]p4:
// [For a] user-provided explicitly-defaulted function [...] if such a
// function is implicitly defined as deleted, the program is ill-formed.
Diag(MD->getLocation(), diag::err_out_of_line_default_deletes) << CSM;
ShouldDeleteSpecialMember(MD, CSM, /*Diagnose*/true);
HadError = true;
}
}
if (HadError)
MD->setInvalidDecl();
}
/// Check whether the exception specification provided for an
/// explicitly-defaulted special member matches the exception specification
/// that would have been generated for an implicit special member, per
/// C++11 [dcl.fct.def.default]p2.
void Sema::CheckExplicitlyDefaultedMemberExceptionSpec(
CXXMethodDecl *MD, const FunctionProtoType *SpecifiedType) {
// Compute the implicit exception specification.
CallingConv CC = Context.getDefaultCallingConvention(/*IsVariadic=*/false,
/*IsCXXMethod=*/true);
FunctionProtoType::ExtProtoInfo EPI(CC);
computeImplicitExceptionSpec(*this, MD->getLocation(), MD).getEPI(EPI);
const FunctionProtoType *ImplicitType = cast<FunctionProtoType>(
Context.getFunctionType(Context.VoidTy, None, EPI));
// Ensure that it matches.
CheckEquivalentExceptionSpec(
PDiag(diag::err_incorrect_defaulted_exception_spec)
<< getSpecialMember(MD), PDiag(),
ImplicitType, SourceLocation(),
SpecifiedType, MD->getLocation());
}
void Sema::CheckDelayedMemberExceptionSpecs() {
SmallVector<std::pair<const CXXDestructorDecl *, const CXXDestructorDecl *>,
2> Checks;
SmallVector<std::pair<CXXMethodDecl *, const FunctionProtoType *>, 2> Specs;
std::swap(Checks, DelayedDestructorExceptionSpecChecks);
std::swap(Specs, DelayedDefaultedMemberExceptionSpecs);
// Perform any deferred checking of exception specifications for virtual
// destructors.
for (unsigned i = 0, e = Checks.size(); i != e; ++i) {
const CXXDestructorDecl *Dtor = Checks[i].first;
assert(!Dtor->getParent()->isDependentType() &&
"Should not ever add destructors of templates into the list.");
CheckOverridingFunctionExceptionSpec(Dtor, Checks[i].second);
}
// Check that any explicitly-defaulted methods have exception specifications
// compatible with their implicit exception specifications.
for (unsigned I = 0, N = Specs.size(); I != N; ++I)
CheckExplicitlyDefaultedMemberExceptionSpec(Specs[I].first,
Specs[I].second);
}
namespace {
struct SpecialMemberDeletionInfo {
Sema &S;
CXXMethodDecl *MD;
Sema::CXXSpecialMember CSM;
bool Diagnose;
// Properties of the special member, computed for convenience.
bool IsConstructor, IsAssignment, IsMove, ConstArg;
SourceLocation Loc;
bool AllFieldsAreConst;
SpecialMemberDeletionInfo(Sema &S, CXXMethodDecl *MD,
Sema::CXXSpecialMember CSM, bool Diagnose)
: S(S), MD(MD), CSM(CSM), Diagnose(Diagnose),
IsConstructor(false), IsAssignment(false), IsMove(false),
ConstArg(false), Loc(MD->getLocation()),
AllFieldsAreConst(true) {
switch (CSM) {
case Sema::CXXDefaultConstructor:
case Sema::CXXCopyConstructor:
IsConstructor = true;
break;
case Sema::CXXMoveConstructor:
IsConstructor = true;
IsMove = true;
break;
case Sema::CXXCopyAssignment:
IsAssignment = true;
break;
case Sema::CXXMoveAssignment:
IsAssignment = true;
IsMove = true;
break;
case Sema::CXXDestructor:
break;
case Sema::CXXInvalid:
llvm_unreachable("invalid special member kind");
}
if (MD->getNumParams()) {
if (const ReferenceType *RT =
MD->getParamDecl(0)->getType()->getAs<ReferenceType>())
ConstArg = RT->getPointeeType().isConstQualified();
}
}
bool inUnion() const { return MD->getParent()->isUnion(); }
/// Look up the corresponding special member in the given class.
Sema::SpecialMemberOverloadResult *lookupIn(CXXRecordDecl *Class,
unsigned Quals, bool IsMutable) {
return lookupCallFromSpecialMember(S, Class, CSM, Quals,
ConstArg && !IsMutable);
}
typedef llvm::PointerUnion<CXXBaseSpecifier*, FieldDecl*> Subobject;
bool shouldDeleteForBase(CXXBaseSpecifier *Base);
bool shouldDeleteForField(FieldDecl *FD);
bool shouldDeleteForAllConstMembers();
bool shouldDeleteForClassSubobject(CXXRecordDecl *Class, Subobject Subobj,
unsigned Quals);
bool shouldDeleteForSubobjectCall(Subobject Subobj,
Sema::SpecialMemberOverloadResult *SMOR,
bool IsDtorCallInCtor);
bool isAccessible(Subobject Subobj, CXXMethodDecl *D);
};
}
/// Is the given special member inaccessible when used on the given
/// sub-object.
bool SpecialMemberDeletionInfo::isAccessible(Subobject Subobj,
CXXMethodDecl *target) {
/// If we're operating on a base class, the object type is the
/// type of this special member.
QualType objectTy;
AccessSpecifier access = target->getAccess();
if (CXXBaseSpecifier *base = Subobj.dyn_cast<CXXBaseSpecifier*>()) {
objectTy = S.Context.getTypeDeclType(MD->getParent());
access = CXXRecordDecl::MergeAccess(base->getAccessSpecifier(), access);
// If we're operating on a field, the object type is the type of the field.
} else {
objectTy = S.Context.getTypeDeclType(target->getParent());
}
return S.isSpecialMemberAccessibleForDeletion(target, access, objectTy);
}
/// Check whether we should delete a special member due to the implicit
/// definition containing a call to a special member of a subobject.
bool SpecialMemberDeletionInfo::shouldDeleteForSubobjectCall(
Subobject Subobj, Sema::SpecialMemberOverloadResult *SMOR,
bool IsDtorCallInCtor) {
CXXMethodDecl *Decl = SMOR->getMethod();
FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
int DiagKind = -1;
if (SMOR->getKind() == Sema::SpecialMemberOverloadResult::NoMemberOrDeleted)
DiagKind = !Decl ? 0 : 1;
else if (SMOR->getKind() == Sema::SpecialMemberOverloadResult::Ambiguous)
DiagKind = 2;
else if (!isAccessible(Subobj, Decl))
DiagKind = 3;
else if (!IsDtorCallInCtor && Field && Field->getParent()->isUnion() &&
!Decl->isTrivial()) {
// A member of a union must have a trivial corresponding special member.
// As a weird special case, a destructor call from a union's constructor
// must be accessible and non-deleted, but need not be trivial. Such a
// destructor is never actually called, but is semantically checked as
// if it were.
DiagKind = 4;
}
if (DiagKind == -1)
return false;
if (Diagnose) {
if (Field) {
S.Diag(Field->getLocation(),
diag::note_deleted_special_member_class_subobject)
<< CSM << MD->getParent() << /*IsField*/true
<< Field << DiagKind << IsDtorCallInCtor;
} else {
CXXBaseSpecifier *Base = Subobj.get<CXXBaseSpecifier*>();
S.Diag(Base->getLocStart(),
diag::note_deleted_special_member_class_subobject)
<< CSM << MD->getParent() << /*IsField*/false
<< Base->getType() << DiagKind << IsDtorCallInCtor;
}
if (DiagKind == 1)
S.NoteDeletedFunction(Decl);
// FIXME: Explain inaccessibility if DiagKind == 3.
}
return true;
}
/// Check whether we should delete a special member function due to having a
/// direct or virtual base class or non-static data member of class type M.
bool SpecialMemberDeletionInfo::shouldDeleteForClassSubobject(
CXXRecordDecl *Class, Subobject Subobj, unsigned Quals) {
FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
bool IsMutable = Field && Field->isMutable();
// C++11 [class.ctor]p5:
// -- any direct or virtual base class, or non-static data member with no
// brace-or-equal-initializer, has class type M (or array thereof) and
// either M has no default constructor or overload resolution as applied
// to M's default constructor results in an ambiguity or in a function
// that is deleted or inaccessible
// C++11 [class.copy]p11, C++11 [class.copy]p23:
// -- a direct or virtual base class B that cannot be copied/moved because
// overload resolution, as applied to B's corresponding special member,
// results in an ambiguity or a function that is deleted or inaccessible
// from the defaulted special member
// C++11 [class.dtor]p5:
// -- any direct or virtual base class [...] has a type with a destructor
// that is deleted or inaccessible
if (!(CSM == Sema::CXXDefaultConstructor &&
Field && Field->hasInClassInitializer()) &&
shouldDeleteForSubobjectCall(Subobj, lookupIn(Class, Quals, IsMutable),
false))
return true;
// C++11 [class.ctor]p5, C++11 [class.copy]p11:
// -- any direct or virtual base class or non-static data member has a
// type with a destructor that is deleted or inaccessible
if (IsConstructor) {
Sema::SpecialMemberOverloadResult *SMOR =
S.LookupSpecialMember(Class, Sema::CXXDestructor,
false, false, false, false, false);
if (shouldDeleteForSubobjectCall(Subobj, SMOR, true))
return true;
}
return false;
}
/// Check whether we should delete a special member function due to the class
/// having a particular direct or virtual base class.
bool SpecialMemberDeletionInfo::shouldDeleteForBase(CXXBaseSpecifier *Base) {
CXXRecordDecl *BaseClass = Base->getType()->getAsCXXRecordDecl();
return shouldDeleteForClassSubobject(BaseClass, Base, 0);
}
/// Check whether we should delete a special member function due to the class
/// having a particular non-static data member.
bool SpecialMemberDeletionInfo::shouldDeleteForField(FieldDecl *FD) {
QualType FieldType = S.Context.getBaseElementType(FD->getType());
CXXRecordDecl *FieldRecord = FieldType->getAsCXXRecordDecl();
if (CSM == Sema::CXXDefaultConstructor) {
// For a default constructor, all references must be initialized in-class
// and, if a union, it must have a non-const member.
if (FieldType->isReferenceType() && !FD->hasInClassInitializer()) {
if (Diagnose)
S.Diag(FD->getLocation(), diag::note_deleted_default_ctor_uninit_field)
<< MD->getParent() << FD << FieldType << /*Reference*/0;
return true;
}
// C++11 [class.ctor]p5: any non-variant non-static data member of
// const-qualified type (or array thereof) with no
// brace-or-equal-initializer does not have a user-provided default
// constructor.
if (!inUnion() && FieldType.isConstQualified() &&
!FD->hasInClassInitializer() &&
(!FieldRecord || !FieldRecord->hasUserProvidedDefaultConstructor())) {
if (Diagnose)
S.Diag(FD->getLocation(), diag::note_deleted_default_ctor_uninit_field)
<< MD->getParent() << FD << FD->getType() << /*Const*/1;
return true;
}
if (inUnion() && !FieldType.isConstQualified())
AllFieldsAreConst = false;
} else if (CSM == Sema::CXXCopyConstructor) {
// For a copy constructor, data members must not be of rvalue reference
// type.
if (FieldType->isRValueReferenceType()) {
if (Diagnose)
S.Diag(FD->getLocation(), diag::note_deleted_copy_ctor_rvalue_reference)
<< MD->getParent() << FD << FieldType;
return true;
}
} else if (IsAssignment) {
// For an assignment operator, data members must not be of reference type.
if (FieldType->isReferenceType()) {
if (Diagnose)
S.Diag(FD->getLocation(), diag::note_deleted_assign_field)
<< IsMove << MD->getParent() << FD << FieldType << /*Reference*/0;
return true;
}
if (!FieldRecord && FieldType.isConstQualified()) {
// C++11 [class.copy]p23:
// -- a non-static data member of const non-class type (or array thereof)
if (Diagnose)
S.Diag(FD->getLocation(), diag::note_deleted_assign_field)
<< IsMove << MD->getParent() << FD << FD->getType() << /*Const*/1;
return true;
}
}
if (FieldRecord) {
// Some additional restrictions exist on the variant members.
if (!inUnion() && FieldRecord->isUnion() &&
FieldRecord->isAnonymousStructOrUnion()) {
bool AllVariantFieldsAreConst = true;
// FIXME: Handle anonymous unions declared within anonymous unions.
for (auto *UI : FieldRecord->fields()) {
QualType UnionFieldType = S.Context.getBaseElementType(UI->getType());
if (!UnionFieldType.isConstQualified())
AllVariantFieldsAreConst = false;
CXXRecordDecl *UnionFieldRecord = UnionFieldType->getAsCXXRecordDecl();
if (UnionFieldRecord &&
shouldDeleteForClassSubobject(UnionFieldRecord, UI,
UnionFieldType.getCVRQualifiers()))
return true;
}
// At least one member in each anonymous union must be non-const
if (CSM == Sema::CXXDefaultConstructor && AllVariantFieldsAreConst &&
!FieldRecord->field_empty()) {
if (Diagnose)
S.Diag(FieldRecord->getLocation(),
diag::note_deleted_default_ctor_all_const)
<< MD->getParent() << /*anonymous union*/1;
return true;
}
// Don't check the implicit member of the anonymous union type.
// This is technically non-conformant, but sanity demands it.
return false;
}
if (shouldDeleteForClassSubobject(FieldRecord, FD,
FieldType.getCVRQualifiers()))
return true;
}
return false;
}
/// C++11 [class.ctor] p5:
/// A defaulted default constructor for a class X is defined as deleted if
/// X is a union and all of its variant members are of const-qualified type.
bool SpecialMemberDeletionInfo::shouldDeleteForAllConstMembers() {
// This is a silly definition, because it gives an empty union a deleted
// default constructor. Don't do that.
if (CSM == Sema::CXXDefaultConstructor && inUnion() && AllFieldsAreConst &&
!MD->getParent()->field_empty()) {
if (Diagnose)
S.Diag(MD->getParent()->getLocation(),
diag::note_deleted_default_ctor_all_const)
<< MD->getParent() << /*not anonymous union*/0;
return true;
}
return false;
}
/// Determine whether a defaulted special member function should be defined as
/// deleted, as specified in C++11 [class.ctor]p5, C++11 [class.copy]p11,
/// C++11 [class.copy]p23, and C++11 [class.dtor]p5.
bool Sema::ShouldDeleteSpecialMember(CXXMethodDecl *MD, CXXSpecialMember CSM,
bool Diagnose) {
if (MD->isInvalidDecl())
return false;
CXXRecordDecl *RD = MD->getParent();
assert(!RD->isDependentType() && "do deletion after instantiation");
if (!LangOpts.CPlusPlus11 || RD->isInvalidDecl())
return false;
// C++11 [expr.lambda.prim]p19:
// The closure type associated with a lambda-expression has a
// deleted (8.4.3) default constructor and a deleted copy
// assignment operator.
if (RD->isLambda() &&
(CSM == CXXDefaultConstructor || CSM == CXXCopyAssignment)) {
if (Diagnose)
Diag(RD->getLocation(), diag::note_lambda_decl);
return true;
}
// For an anonymous struct or union, the copy and assignment special members
// will never be used, so skip the check. For an anonymous union declared at
// namespace scope, the constructor and destructor are used.
if (CSM != CXXDefaultConstructor && CSM != CXXDestructor &&
RD->isAnonymousStructOrUnion())
return false;
// C++11 [class.copy]p7, p18:
// If the class definition declares a move constructor or move assignment
// operator, an implicitly declared copy constructor or copy assignment
// operator is defined as deleted.
if (MD->isImplicit() &&
(CSM == CXXCopyConstructor || CSM == CXXCopyAssignment)) {
CXXMethodDecl *UserDeclaredMove = nullptr;
// In Microsoft mode, a user-declared move only causes the deletion of the
// corresponding copy operation, not both copy operations.
if (RD->hasUserDeclaredMoveConstructor() &&
(!getLangOpts().MSVCCompat || CSM == CXXCopyConstructor)) {
if (!Diagnose) return true;
// Find any user-declared move constructor.
for (auto *I : RD->ctors()) {
if (I->isMoveConstructor()) {
UserDeclaredMove = I;
break;
}
}
assert(UserDeclaredMove);
} else if (RD->hasUserDeclaredMoveAssignment() &&
(!getLangOpts().MSVCCompat || CSM == CXXCopyAssignment)) {
if (!Diagnose) return true;
// Find any user-declared move assignment operator.
for (auto *I : RD->methods()) {
if (I->isMoveAssignmentOperator()) {
UserDeclaredMove = I;
break;
}
}
assert(UserDeclaredMove);
}
if (UserDeclaredMove) {
Diag(UserDeclaredMove->getLocation(),
diag::note_deleted_copy_user_declared_move)
<< (CSM == CXXCopyAssignment) << RD
<< UserDeclaredMove->isMoveAssignmentOperator();
return true;
}
}
// Do access control from the special member function
ContextRAII MethodContext(*this, MD);
// C++11 [class.dtor]p5:
// -- for a virtual destructor, lookup of the non-array deallocation function
// results in an ambiguity or in a function that is deleted or inaccessible
if (CSM == CXXDestructor && MD->isVirtual()) {
FunctionDecl *OperatorDelete = nullptr;
DeclarationName Name =
Context.DeclarationNames.getCXXOperatorName(OO_Delete);
if (FindDeallocationFunction(MD->getLocation(), MD->getParent(), Name,
OperatorDelete, false)) {
if (Diagnose)
Diag(RD->getLocation(), diag::note_deleted_dtor_no_operator_delete);
return true;
}
}
SpecialMemberDeletionInfo SMI(*this, MD, CSM, Diagnose);
for (auto &BI : RD->bases())
if (!BI.isVirtual() &&
SMI.shouldDeleteForBase(&BI))
return true;
// Per DR1611, do not consider virtual bases of constructors of abstract
// classes, since we are not going to construct them.
if (!RD->isAbstract() || !SMI.IsConstructor) {
for (auto &BI : RD->vbases())
if (SMI.shouldDeleteForBase(&BI))
return true;
}
for (auto *FI : RD->fields())
if (!FI->isInvalidDecl() && !FI->isUnnamedBitfield() &&
SMI.shouldDeleteForField(FI))
return true;
if (SMI.shouldDeleteForAllConstMembers())
return true;
return false;
}
/// Perform lookup for a special member of the specified kind, and determine
/// whether it is trivial. If the triviality can be determined without the
/// lookup, skip it. This is intended for use when determining whether a
/// special member of a containing object is trivial, and thus does not ever
/// perform overload resolution for default constructors.
///
/// If \p Selected is not \c NULL, \c *Selected will be filled in with the
/// member that was most likely to be intended to be trivial, if any.
static bool findTrivialSpecialMember(Sema &S, CXXRecordDecl *RD,
Sema::CXXSpecialMember CSM, unsigned Quals,
bool ConstRHS, CXXMethodDecl **Selected) {
if (Selected)
*Selected = nullptr;
switch (CSM) {
case Sema::CXXInvalid:
llvm_unreachable("not a special member");
case Sema::CXXDefaultConstructor:
// C++11 [class.ctor]p5:
// A default constructor is trivial if:
// - all the [direct subobjects] have trivial default constructors
//
// Note, no overload resolution is performed in this case.
if (RD->hasTrivialDefaultConstructor())
return true;
if (Selected) {
// If there's a default constructor which could have been trivial, dig it
// out. Otherwise, if there's any user-provided default constructor, point
// to that as an example of why there's not a trivial one.
CXXConstructorDecl *DefCtor = nullptr;
if (RD->needsImplicitDefaultConstructor())
S.DeclareImplicitDefaultConstructor(RD);
for (auto *CI : RD->ctors()) {
if (!CI->isDefaultConstructor())
continue;
DefCtor = CI;
if (!DefCtor->isUserProvided())
break;
}
*Selected = DefCtor;
}
return false;
case Sema::CXXDestructor:
// C++11 [class.dtor]p5:
// A destructor is trivial if:
// - all the direct [subobjects] have trivial destructors
if (RD->hasTrivialDestructor())
return true;
if (Selected) {
if (RD->needsImplicitDestructor())
S.DeclareImplicitDestructor(RD);
*Selected = RD->getDestructor();
}
return false;
case Sema::CXXCopyConstructor:
// C++11 [class.copy]p12:
// A copy constructor is trivial if:
// - the constructor selected to copy each direct [subobject] is trivial
if (RD->hasTrivialCopyConstructor()) {
if (Quals == Qualifiers::Const)
// We must either select the trivial copy constructor or reach an
// ambiguity; no need to actually perform overload resolution.
return true;
} else if (!Selected) {
return false;
}
// In C++98, we are not supposed to perform overload resolution here, but we
// treat that as a language defect, as suggested on cxx-abi-dev, to treat
// cases like B as having a non-trivial copy constructor:
// struct A { template<typename T> A(T&); };
// struct B { mutable A a; };
goto NeedOverloadResolution;
case Sema::CXXCopyAssignment:
// C++11 [class.copy]p25:
// A copy assignment operator is trivial if:
// - the assignment operator selected to copy each direct [subobject] is
// trivial
if (RD->hasTrivialCopyAssignment()) {
if (Quals == Qualifiers::Const)
return true;
} else if (!Selected) {
return false;
}
// In C++98, we are not supposed to perform overload resolution here, but we
// treat that as a language defect.
goto NeedOverloadResolution;
case Sema::CXXMoveConstructor:
case Sema::CXXMoveAssignment:
NeedOverloadResolution:
Sema::SpecialMemberOverloadResult *SMOR =
lookupCallFromSpecialMember(S, RD, CSM, Quals, ConstRHS);
// The standard doesn't describe how to behave if the lookup is ambiguous.
// We treat it as not making the member non-trivial, just like the standard
// mandates for the default constructor. This should rarely matter, because
// the member will also be deleted.
if (SMOR->getKind() == Sema::SpecialMemberOverloadResult::Ambiguous)
return true;
if (!SMOR->getMethod()) {
assert(SMOR->getKind() ==
Sema::SpecialMemberOverloadResult::NoMemberOrDeleted);
return false;
}
// We deliberately don't check if we found a deleted special member. We're
// not supposed to!
if (Selected)
*Selected = SMOR->getMethod();
return SMOR->getMethod()->isTrivial();
}
llvm_unreachable("unknown special method kind");
}
static CXXConstructorDecl *findUserDeclaredCtor(CXXRecordDecl *RD) {
for (auto *CI : RD->ctors())
if (!CI->isImplicit())
return CI;
// Look for constructor templates.
typedef CXXRecordDecl::specific_decl_iterator<FunctionTemplateDecl> tmpl_iter;
for (tmpl_iter TI(RD->decls_begin()), TE(RD->decls_end()); TI != TE; ++TI) {
if (CXXConstructorDecl *CD =
dyn_cast<CXXConstructorDecl>(TI->getTemplatedDecl()))
return CD;
}
return nullptr;
}
/// The kind of subobject we are checking for triviality. The values of this
/// enumeration are used in diagnostics.
enum TrivialSubobjectKind {
/// The subobject is a base class.
TSK_BaseClass,
/// The subobject is a non-static data member.
TSK_Field,
/// The object is actually the complete object.
TSK_CompleteObject
};
/// Check whether the special member selected for a given type would be trivial.
static bool checkTrivialSubobjectCall(Sema &S, SourceLocation SubobjLoc,
QualType SubType, bool ConstRHS,
Sema::CXXSpecialMember CSM,
TrivialSubobjectKind Kind,
bool Diagnose) {
CXXRecordDecl *SubRD = SubType->getAsCXXRecordDecl();
if (!SubRD)
return true;
CXXMethodDecl *Selected;
if (findTrivialSpecialMember(S, SubRD, CSM, SubType.getCVRQualifiers(),
ConstRHS, Diagnose ? &Selected : nullptr))
return true;
if (Diagnose) {
if (ConstRHS)
SubType.addConst();
if (!Selected && CSM == Sema::CXXDefaultConstructor) {
S.Diag(SubobjLoc, diag::note_nontrivial_no_def_ctor)
<< Kind << SubType.getUnqualifiedType();
if (CXXConstructorDecl *CD = findUserDeclaredCtor(SubRD))
S.Diag(CD->getLocation(), diag::note_user_declared_ctor);
} else if (!Selected)
S.Diag(SubobjLoc, diag::note_nontrivial_no_copy)
<< Kind << SubType.getUnqualifiedType() << CSM << SubType;
else if (Selected->isUserProvided()) {
if (Kind == TSK_CompleteObject)
S.Diag(Selected->getLocation(), diag::note_nontrivial_user_provided)
<< Kind << SubType.getUnqualifiedType() << CSM;
else {
S.Diag(SubobjLoc, diag::note_nontrivial_user_provided)
<< Kind << SubType.getUnqualifiedType() << CSM;
S.Diag(Selected->getLocation(), diag::note_declared_at);
}
} else {
if (Kind != TSK_CompleteObject)
S.Diag(SubobjLoc, diag::note_nontrivial_subobject)
<< Kind << SubType.getUnqualifiedType() << CSM;
// Explain why the defaulted or deleted special member isn't trivial.
S.SpecialMemberIsTrivial(Selected, CSM, Diagnose);
}
}
return false;
}
/// Check whether the members of a class type allow a special member to be
/// trivial.
static bool checkTrivialClassMembers(Sema &S, CXXRecordDecl *RD,
Sema::CXXSpecialMember CSM,
bool ConstArg, bool Diagnose) {
for (const auto *FI : RD->fields()) {
if (FI->isInvalidDecl() || FI->isUnnamedBitfield())
continue;
QualType FieldType = S.Context.getBaseElementType(FI->getType());
// Pretend anonymous struct or union members are members of this class.
if (FI->isAnonymousStructOrUnion()) {
if (!checkTrivialClassMembers(S, FieldType->getAsCXXRecordDecl(),
CSM, ConstArg, Diagnose))
return false;
continue;
}
// C++11 [class.ctor]p5:
// A default constructor is trivial if [...]
// -- no non-static data member of its class has a
// brace-or-equal-initializer
if (CSM == Sema::CXXDefaultConstructor && FI->hasInClassInitializer()) {
if (Diagnose)
S.Diag(FI->getLocation(), diag::note_nontrivial_in_class_init) << FI;
return false;
}
// Objective C ARC 4.3.5:
// [...] nontrivally ownership-qualified types are [...] not trivially
// default constructible, copy constructible, move constructible, copy
// assignable, move assignable, or destructible [...]
if (S.getLangOpts().ObjCAutoRefCount &&
FieldType.hasNonTrivialObjCLifetime()) {
if (Diagnose)
S.Diag(FI->getLocation(), diag::note_nontrivial_objc_ownership)
<< RD << FieldType.getObjCLifetime();
return false;
}
bool ConstRHS = ConstArg && !FI->isMutable();
if (!checkTrivialSubobjectCall(S, FI->getLocation(), FieldType, ConstRHS,
CSM, TSK_Field, Diagnose))
return false;
}
return true;
}
/// Diagnose why the specified class does not have a trivial special member of
/// the given kind.
void Sema::DiagnoseNontrivial(const CXXRecordDecl *RD, CXXSpecialMember CSM) {
QualType Ty = Context.getRecordType(RD);
bool ConstArg = (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment);
checkTrivialSubobjectCall(*this, RD->getLocation(), Ty, ConstArg, CSM,
TSK_CompleteObject, /*Diagnose*/true);
}
/// Determine whether a defaulted or deleted special member function is trivial,
/// as specified in C++11 [class.ctor]p5, C++11 [class.copy]p12,
/// C++11 [class.copy]p25, and C++11 [class.dtor]p5.
bool Sema::SpecialMemberIsTrivial(CXXMethodDecl *MD, CXXSpecialMember CSM,
bool Diagnose) {
assert(!MD->isUserProvided() && CSM != CXXInvalid && "not special enough");
CXXRecordDecl *RD = MD->getParent();
bool ConstArg = false;
// C++11 [class.copy]p12, p25: [DR1593]
// A [special member] is trivial if [...] its parameter-type-list is
// equivalent to the parameter-type-list of an implicit declaration [...]
switch (CSM) {
case CXXDefaultConstructor:
case CXXDestructor:
// Trivial default constructors and destructors cannot have parameters.
break;
case CXXCopyConstructor:
case CXXCopyAssignment: {
// Trivial copy operations always have const, non-volatile parameter types.
ConstArg = true;
const ParmVarDecl *Param0 = MD->getParamDecl(0);
const ReferenceType *RT = Param0->getType()->getAs<ReferenceType>();
if (!RT || RT->getPointeeType().getCVRQualifiers() != Qualifiers::Const) {
if (Diagnose)
Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
<< Param0->getSourceRange() << Param0->getType()
<< Context.getLValueReferenceType(
Context.getRecordType(RD).withConst());
return false;
}
break;
}
case CXXMoveConstructor:
case CXXMoveAssignment: {
// Trivial move operations always have non-cv-qualified parameters.
const ParmVarDecl *Param0 = MD->getParamDecl(0);
const RValueReferenceType *RT =
Param0->getType()->getAs<RValueReferenceType>();
if (!RT || RT->getPointeeType().getCVRQualifiers()) {
if (Diagnose)
Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
<< Param0->getSourceRange() << Param0->getType()
<< Context.getRValueReferenceType(Context.getRecordType(RD));
return false;
}
break;
}
case CXXInvalid:
llvm_unreachable("not a special member");
}
if (MD->getMinRequiredArguments() < MD->getNumParams()) {
if (Diagnose)
Diag(MD->getParamDecl(MD->getMinRequiredArguments())->getLocation(),
diag::note_nontrivial_default_arg)
<< MD->getParamDecl(MD->getMinRequiredArguments())->getSourceRange();
return false;
}
if (MD->isVariadic()) {
if (Diagnose)
Diag(MD->getLocation(), diag::note_nontrivial_variadic);
return false;
}
// C++11 [class.ctor]p5, C++11 [class.dtor]p5:
// A copy/move [constructor or assignment operator] is trivial if
// -- the [member] selected to copy/move each direct base class subobject
// is trivial
//
// C++11 [class.copy]p12, C++11 [class.copy]p25:
// A [default constructor or destructor] is trivial if
// -- all the direct base classes have trivial [default constructors or
// destructors]
for (const auto &BI : RD->bases())
if (!checkTrivialSubobjectCall(*this, BI.getLocStart(), BI.getType(),
ConstArg, CSM, TSK_BaseClass, Diagnose))
return false;
// C++11 [class.ctor]p5, C++11 [class.dtor]p5:
// A copy/move [constructor or assignment operator] for a class X is
// trivial if
// -- for each non-static data member of X that is of class type (or array
// thereof), the constructor selected to copy/move that member is
// trivial
//
// C++11 [class.copy]p12, C++11 [class.copy]p25:
// A [default constructor or destructor] is trivial if
// -- for all of the non-static data members of its class that are of class
// type (or array thereof), each such class has a trivial [default
// constructor or destructor]
if (!checkTrivialClassMembers(*this, RD, CSM, ConstArg, Diagnose))
return false;
// C++11 [class.dtor]p5:
// A destructor is trivial if [...]
// -- the destructor is not virtual
if (CSM == CXXDestructor && MD->isVirtual()) {
if (Diagnose)
Diag(MD->getLocation(), diag::note_nontrivial_virtual_dtor) << RD;
return false;
}
// C++11 [class.ctor]p5, C++11 [class.copy]p12, C++11 [class.copy]p25:
// A [special member] for class X is trivial if [...]
// -- class X has no virtual functions and no virtual base classes
if (CSM != CXXDestructor && MD->getParent()->isDynamicClass()) {
if (!Diagnose)
return false;
if (RD->getNumVBases()) {
// Check for virtual bases. We already know that the corresponding
// member in all bases is trivial, so vbases must all be direct.
CXXBaseSpecifier &BS = *RD->vbases_begin();
assert(BS.isVirtual());
Diag(BS.getLocStart(), diag::note_nontrivial_has_virtual) << RD << 1;
return false;
}
// Must have a virtual method.
for (const auto *MI : RD->methods()) {
if (MI->isVirtual()) {
SourceLocation MLoc = MI->getLocStart();
Diag(MLoc, diag::note_nontrivial_has_virtual) << RD << 0;
return false;
}
}
llvm_unreachable("dynamic class with no vbases and no virtual functions");
}
// Looks like it's trivial!
return true;
}
/// \brief Data used with FindHiddenVirtualMethod
namespace {
struct FindHiddenVirtualMethodData {
Sema *S;
CXXMethodDecl *Method;
llvm::SmallPtrSet<const CXXMethodDecl *, 8> OverridenAndUsingBaseMethods;
SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
};
}
/// \brief Check whether any most overriden method from MD in Methods
static bool CheckMostOverridenMethods(const CXXMethodDecl *MD,
const llvm::SmallPtrSet<const CXXMethodDecl *, 8>& Methods) {
if (MD->size_overridden_methods() == 0)
return Methods.count(MD->getCanonicalDecl());
for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
E = MD->end_overridden_methods();
I != E; ++I)
if (CheckMostOverridenMethods(*I, Methods))
return true;
return false;
}
/// \brief Member lookup function that determines whether a given C++
/// method overloads virtual methods in a base class without overriding any,
/// to be used with CXXRecordDecl::lookupInBases().
static bool FindHiddenVirtualMethod(const CXXBaseSpecifier *Specifier,
CXXBasePath &Path,
void *UserData) {
RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();
FindHiddenVirtualMethodData &Data
= *static_cast<FindHiddenVirtualMethodData*>(UserData);
DeclarationName Name = Data.Method->getDeclName();
assert(Name.getNameKind() == DeclarationName::Identifier);
bool foundSameNameMethod = false;
SmallVector<CXXMethodDecl *, 8> overloadedMethods;
for (Path.Decls = BaseRecord->lookup(Name);
!Path.Decls.empty();
Path.Decls = Path.Decls.slice(1)) {
NamedDecl *D = Path.Decls.front();
if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
MD = MD->getCanonicalDecl();
foundSameNameMethod = true;
// Interested only in hidden virtual methods.
if (!MD->isVirtual())
continue;
// If the method we are checking overrides a method from its base
// don't warn about the other overloaded methods.
if (!Data.S->IsOverload(Data.Method, MD, false))
return true;
// Collect the overload only if its hidden.
if (!CheckMostOverridenMethods(MD, Data.OverridenAndUsingBaseMethods))
overloadedMethods.push_back(MD);
}
}
if (foundSameNameMethod)
Data.OverloadedMethods.append(overloadedMethods.begin(),
overloadedMethods.end());
return foundSameNameMethod;
}
/// \brief Add the most overriden methods from MD to Methods
static void AddMostOverridenMethods(const CXXMethodDecl *MD,
llvm::SmallPtrSet<const CXXMethodDecl *, 8>& Methods) {
if (MD->size_overridden_methods() == 0)
Methods.insert(MD->getCanonicalDecl());
for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
E = MD->end_overridden_methods();
I != E; ++I)
AddMostOverridenMethods(*I, Methods);
}
/// \brief Check if a method overloads virtual methods in a base class without
/// overriding any.
void Sema::FindHiddenVirtualMethods(CXXMethodDecl *MD,
SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods) {
if (!MD->getDeclName().isIdentifier())
return;
CXXBasePaths Paths(/*FindAmbiguities=*/true, // true to look in all bases.
/*bool RecordPaths=*/false,
/*bool DetectVirtual=*/false);
FindHiddenVirtualMethodData Data;
Data.Method = MD;
Data.S = this;
// Keep the base methods that were overriden or introduced in the subclass
// by 'using' in a set. A base method not in this set is hidden.
CXXRecordDecl *DC = MD->getParent();
DeclContext::lookup_result R = DC->lookup(MD->getDeclName());
for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E; ++I) {
NamedDecl *ND = *I;
if (UsingShadowDecl *shad = dyn_cast<UsingShadowDecl>(*I))
ND = shad->getTargetDecl();
if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND))
AddMostOverridenMethods(MD, Data.OverridenAndUsingBaseMethods);
}
if (DC->lookupInBases(&FindHiddenVirtualMethod, &Data, Paths))
OverloadedMethods = Data.OverloadedMethods;
}
void Sema::NoteHiddenVirtualMethods(CXXMethodDecl *MD,
SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods) {
for (unsigned i = 0, e = OverloadedMethods.size(); i != e; ++i) {
CXXMethodDecl *overloadedMD = OverloadedMethods[i];
PartialDiagnostic PD = PDiag(
diag::note_hidden_overloaded_virtual_declared_here) << overloadedMD;
HandleFunctionTypeMismatch(PD, MD->getType(), overloadedMD->getType());
Diag(overloadedMD->getLocation(), PD);
}
}
/// \brief Diagnose methods which overload virtual methods in a base class
/// without overriding any.
void Sema::DiagnoseHiddenVirtualMethods(CXXMethodDecl *MD) {
if (MD->isInvalidDecl())
return;
if (Diags.isIgnored(diag::warn_overloaded_virtual, MD->getLocation()))
return;
SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
FindHiddenVirtualMethods(MD, OverloadedMethods);
if (!OverloadedMethods.empty()) {
Diag(MD->getLocation(), diag::warn_overloaded_virtual)
<< MD << (OverloadedMethods.size() > 1);
NoteHiddenVirtualMethods(MD, OverloadedMethods);
}
}
void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc,
Decl *TagDecl,
SourceLocation LBrac,
SourceLocation RBrac,
AttributeList *AttrList) {
if (!TagDecl)
return;
AdjustDeclIfTemplate(TagDecl);
for (const AttributeList* l = AttrList; l; l = l->getNext()) {
if (l->getKind() != AttributeList::AT_Visibility)
continue;
l->setInvalid();
Diag(l->getLoc(), diag::warn_attribute_after_definition_ignored) <<
l->getName();
}
ActOnFields(S, RLoc, TagDecl, llvm::makeArrayRef(
// strict aliasing violation!
reinterpret_cast<Decl**>(FieldCollector->getCurFields()),
FieldCollector->getCurNumFields()), LBrac, RBrac, AttrList);
CheckCompletedCXXClass(
dyn_cast_or_null<CXXRecordDecl>(TagDecl));
}
/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared
/// special functions, such as the default constructor, copy
/// constructor, or destructor, to the given C++ class (C++
/// [special]p1). This routine can only be executed just before the
/// definition of the class is complete.
void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) {
if (!ClassDecl->hasUserDeclaredConstructor())
++ASTContext::NumImplicitDefaultConstructors;
if (!ClassDecl->hasUserDeclaredCopyConstructor()) {
++ASTContext::NumImplicitCopyConstructors;
// If the properties or semantics of the copy constructor couldn't be
// determined while the class was being declared, force a declaration
// of it now.
if (ClassDecl->needsOverloadResolutionForCopyConstructor())
DeclareImplicitCopyConstructor(ClassDecl);
}
if (getLangOpts().CPlusPlus11 && ClassDecl->needsImplicitMoveConstructor()) {
++ASTContext::NumImplicitMoveConstructors;
if (ClassDecl->needsOverloadResolutionForMoveConstructor())
DeclareImplicitMoveConstructor(ClassDecl);
}
if (!ClassDecl->hasUserDeclaredCopyAssignment()) {
++ASTContext::NumImplicitCopyAssignmentOperators;
// If we have a dynamic class, then the copy assignment operator may be
// virtual, so we have to declare it immediately. This ensures that, e.g.,
// it shows up in the right place in the vtable and that we diagnose
// problems with the implicit exception specification.
if (ClassDecl->isDynamicClass() ||
ClassDecl->needsOverloadResolutionForCopyAssignment())
DeclareImplicitCopyAssignment(ClassDecl);
}
if (getLangOpts().CPlusPlus11 && ClassDecl->needsImplicitMoveAssignment()) {
++ASTContext::NumImplicitMoveAssignmentOperators;
// Likewise for the move assignment operator.
if (ClassDecl->isDynamicClass() ||
ClassDecl->needsOverloadResolutionForMoveAssignment())
DeclareImplicitMoveAssignment(ClassDecl);
}
if (!ClassDecl->hasUserDeclaredDestructor()) {
++ASTContext::NumImplicitDestructors;
// If we have a dynamic class, then the destructor may be virtual, so we
// have to declare the destructor immediately. This ensures that, e.g., it
// shows up in the right place in the vtable and that we diagnose problems
// with the implicit exception specification.
if (ClassDecl->isDynamicClass() ||
ClassDecl->needsOverloadResolutionForDestructor())
DeclareImplicitDestructor(ClassDecl);
}
}
unsigned Sema::ActOnReenterTemplateScope(Scope *S, Decl *D) {
if (!D)
return 0;
// The order of template parameters is not important here. All names
// get added to the same scope.
SmallVector<TemplateParameterList *, 4> ParameterLists;
if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
D = TD->getTemplatedDecl();
if (auto *PSD = dyn_cast<ClassTemplatePartialSpecializationDecl>(D))
ParameterLists.push_back(PSD->getTemplateParameters());
if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)) {
for (unsigned i = 0; i < DD->getNumTemplateParameterLists(); ++i)
ParameterLists.push_back(DD->getTemplateParameterList(i));
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
if (FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
ParameterLists.push_back(FTD->getTemplateParameters());
}
}
if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
for (unsigned i = 0; i < TD->getNumTemplateParameterLists(); ++i)
ParameterLists.push_back(TD->getTemplateParameterList(i));
if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) {
if (ClassTemplateDecl *CTD = RD->getDescribedClassTemplate())
ParameterLists.push_back(CTD->getTemplateParameters());
}
}
unsigned Count = 0;
for (TemplateParameterList *Params : ParameterLists) {
if (Params->size() > 0)
// Ignore explicit specializations; they don't contribute to the template
// depth.
++Count;
for (NamedDecl *Param : *Params) {
if (Param->getDeclName()) {
S->AddDecl(Param);
IdResolver.AddDecl(Param);
}
}
}
return Count;
}
void Sema::ActOnStartDelayedMemberDeclarations(Scope *S, Decl *RecordD) {
if (!RecordD) return;
AdjustDeclIfTemplate(RecordD);
CXXRecordDecl *Record = cast<CXXRecordDecl>(RecordD);
PushDeclContext(S, Record);
}
void Sema::ActOnFinishDelayedMemberDeclarations(Scope *S, Decl *RecordD) {
if (!RecordD) return;
PopDeclContext();
}
/// This is used to implement the constant expression evaluation part of the
/// attribute enable_if extension. There is nothing in standard C++ which would
/// require reentering parameters.
void Sema::ActOnReenterCXXMethodParameter(Scope *S, ParmVarDecl *Param) {
if (!Param)
return;
S->AddDecl(Param);
if (Param->getDeclName())
IdResolver.AddDecl(Param);
}
/// ActOnStartDelayedCXXMethodDeclaration - We have completed
/// parsing a top-level (non-nested) C++ class, and we are now
/// parsing those parts of the given Method declaration that could
/// not be parsed earlier (C++ [class.mem]p2), such as default
/// arguments. This action should enter the scope of the given
/// Method declaration as if we had just parsed the qualified method
/// name. However, it should not bring the parameters into scope;
/// that will be performed by ActOnDelayedCXXMethodParameter.
void Sema::ActOnStartDelayedCXXMethodDeclaration(Scope *S, Decl *MethodD) {
}
/// ActOnDelayedCXXMethodParameter - We've already started a delayed
/// C++ method declaration. We're (re-)introducing the given
/// function parameter into scope for use in parsing later parts of
/// the method declaration. For example, we could see an
/// ActOnParamDefaultArgument event for this parameter.
void Sema::ActOnDelayedCXXMethodParameter(Scope *S, Decl *ParamD) {
if (!ParamD)
return;
ParmVarDecl *Param = cast<ParmVarDecl>(ParamD);
// If this parameter has an unparsed default argument, clear it out
// to make way for the parsed default argument.
if (Param->hasUnparsedDefaultArg())
Param->setDefaultArg(nullptr);
S->AddDecl(Param);
if (Param->getDeclName())
IdResolver.AddDecl(Param);
}
/// ActOnFinishDelayedCXXMethodDeclaration - We have finished
/// processing the delayed method declaration for Method. The method
/// declaration is now considered finished. There may be a separate
/// ActOnStartOfFunctionDef action later (not necessarily
/// immediately!) for this method, if it was also defined inside the
/// class body.
void Sema::ActOnFinishDelayedCXXMethodDeclaration(Scope *S, Decl *MethodD) {
if (!MethodD)
return;
AdjustDeclIfTemplate(MethodD);
FunctionDecl *Method = cast<FunctionDecl>(MethodD);
// Now that we have our default arguments, check the constructor
// again. It could produce additional diagnostics or affect whether
// the class has implicitly-declared destructors, among other
// things.
if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Method))
CheckConstructor(Constructor);
// Check the default arguments, which we may have added.
if (!Method->isInvalidDecl())
CheckCXXDefaultArguments(Method);
}
/// CheckConstructorDeclarator - Called by ActOnDeclarator to check
/// the well-formedness of the constructor declarator @p D with type @p
/// R. If there are any errors in the declarator, this routine will
/// emit diagnostics and set the invalid bit to true. In any case, the type
/// will be updated to reflect a well-formed type for the constructor and
/// returned.
QualType Sema::CheckConstructorDeclarator(Declarator &D, QualType R,
StorageClass &SC) {
bool isVirtual = D.getDeclSpec().isVirtualSpecified();
// C++ [class.ctor]p3:
// A constructor shall not be virtual (10.3) or static (9.4). A
// constructor can be invoked for a const, volatile or const
// volatile object. A constructor shall not be declared const,
// volatile, or const volatile (9.3.2).
if (isVirtual) {
if (!D.isInvalidType())
Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be)
<< "virtual" << SourceRange(D.getDeclSpec().getVirtualSpecLoc())
<< SourceRange(D.getIdentifierLoc());
D.setInvalidType();
}
if (SC == SC_Static) {
if (!D.isInvalidType())
Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be)
<< "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
<< SourceRange(D.getIdentifierLoc());
D.setInvalidType();
SC = SC_None;
}
if (unsigned TypeQuals = D.getDeclSpec().getTypeQualifiers()) {
diagnoseIgnoredQualifiers(
diag::err_constructor_return_type, TypeQuals, SourceLocation(),
D.getDeclSpec().getConstSpecLoc(), D.getDeclSpec().getVolatileSpecLoc(),
D.getDeclSpec().getRestrictSpecLoc(),
D.getDeclSpec().getAtomicSpecLoc());
D.setInvalidType();
}
DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
if (FTI.TypeQuals != 0) {
if (FTI.TypeQuals & Qualifiers::Const)
Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor)
<< "const" << SourceRange(D.getIdentifierLoc());
if (FTI.TypeQuals & Qualifiers::Volatile)
Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor)
<< "volatile" << SourceRange(D.getIdentifierLoc());
if (FTI.TypeQuals & Qualifiers::Restrict)
Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor)
<< "restrict" << SourceRange(D.getIdentifierLoc());
D.setInvalidType();
}
// C++0x [class.ctor]p4:
// A constructor shall not be declared with a ref-qualifier.
if (FTI.hasRefQualifier()) {
Diag(FTI.getRefQualifierLoc(), diag::err_ref_qualifier_constructor)
<< FTI.RefQualifierIsLValueRef
<< FixItHint::CreateRemoval(FTI.getRefQualifierLoc());
D.setInvalidType();
}
// Rebuild the function type "R" without any type qualifiers (in
// case any of the errors above fired) and with "void" as the
// return type, since constructors don't have return types.
const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
if (Proto->getReturnType() == Context.VoidTy && !D.isInvalidType())
return R;
FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
EPI.TypeQuals = 0;
EPI.RefQualifier = RQ_None;
return Context.getFunctionType(Context.VoidTy, Proto->getParamTypes(), EPI);
}
/// CheckConstructor - Checks a fully-formed constructor for
/// well-formedness, issuing any diagnostics required. Returns true if
/// the constructor declarator is invalid.
void Sema::CheckConstructor(CXXConstructorDecl *Constructor) {
CXXRecordDecl *ClassDecl
= dyn_cast<CXXRecordDecl>(Constructor->getDeclContext());
if (!ClassDecl)
return Constructor->setInvalidDecl();
// C++ [class.copy]p3:
// A declaration of a constructor for a class X is ill-formed if
// its first parameter is of type (optionally cv-qualified) X and
// either there are no other parameters or else all other
// parameters have default arguments.
if (!Constructor->isInvalidDecl() &&
((Constructor->getNumParams() == 1) ||
(Constructor->getNumParams() > 1 &&
Constructor->getParamDecl(1)->hasDefaultArg())) &&
Constructor->getTemplateSpecializationKind()
!= TSK_ImplicitInstantiation) {
QualType ParamType = Constructor->getParamDecl(0)->getType();
QualType ClassTy = Context.getTagDeclType(ClassDecl);
if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) {
SourceLocation ParamLoc = Constructor->getParamDecl(0)->getLocation();
const char *ConstRef
= Constructor->getParamDecl(0)->getIdentifier() ? "const &"
: " const &";
Diag(ParamLoc, diag::err_constructor_byvalue_arg)
<< FixItHint::CreateInsertion(ParamLoc, ConstRef);
// FIXME: Rather that making the constructor invalid, we should endeavor
// to fix the type.
Constructor->setInvalidDecl();
}
}
}
/// CheckDestructor - Checks a fully-formed destructor definition for
/// well-formedness, issuing any diagnostics required. Returns true
/// on error.
bool Sema::CheckDestructor(CXXDestructorDecl *Destructor) {
CXXRecordDecl *RD = Destructor->getParent();
if (!Destructor->getOperatorDelete() && Destructor->isVirtual()) {
SourceLocation Loc;
if (!Destructor->isImplicit())
Loc = Destructor->getLocation();
else
Loc = RD->getLocation();
// If we have a virtual destructor, look up the deallocation function
FunctionDecl *OperatorDelete = nullptr;
DeclarationName Name =
Context.DeclarationNames.getCXXOperatorName(OO_Delete);
if (FindDeallocationFunction(Loc, RD, Name, OperatorDelete))
return true;
// If there's no class-specific operator delete, look up the global
// non-array delete.
if (!OperatorDelete)
OperatorDelete = FindUsualDeallocationFunction(Loc, true, Name);
MarkFunctionReferenced(Loc, OperatorDelete);
Destructor->setOperatorDelete(OperatorDelete);
}
return false;
}
/// CheckDestructorDeclarator - Called by ActOnDeclarator to check
/// the well-formednes of the destructor declarator @p D with type @p
/// R. If there are any errors in the declarator, this routine will
/// emit diagnostics and set the declarator to invalid. Even if this happens,
/// will be updated to reflect a well-formed type for the destructor and
/// returned.
QualType Sema::CheckDestructorDeclarator(Declarator &D, QualType R,
StorageClass& SC) {
// C++ [class.dtor]p1:
// [...] A typedef-name that names a class is a class-name
// (7.1.3); however, a typedef-name that names a class shall not
// be used as the identifier in the declarator for a destructor
// declaration.
QualType DeclaratorType = GetTypeFromParser(D.getName().DestructorName);
if (const TypedefType *TT = DeclaratorType->getAs<TypedefType>())
Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name)
<< DeclaratorType << isa<TypeAliasDecl>(TT->getDecl());
else if (const TemplateSpecializationType *TST =
DeclaratorType->getAs<TemplateSpecializationType>())
if (TST->isTypeAlias())
Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name)
<< DeclaratorType << 1;
// C++ [class.dtor]p2:
// A destructor is used to destroy objects of its class type. A
// destructor takes no parameters, and no return type can be
// specified for it (not even void). The address of a destructor
// shall not be taken. A destructor shall not be static. A
// destructor can be invoked for a const, volatile or const
// volatile object. A destructor shall not be declared const,
// volatile or const volatile (9.3.2).
if (SC == SC_Static) {
if (!D.isInvalidType())
Diag(D.getIdentifierLoc(), diag::err_destructor_cannot_be)
<< "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
<< SourceRange(D.getIdentifierLoc())
<< FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
SC = SC_None;
}
if (!D.isInvalidType()) {
// Destructors don't have return types, but the parser will
// happily parse something like:
//
// class X {
// float ~X();
// };
//
// The return type will be eliminated later.
if (D.getDeclSpec().hasTypeSpecifier())
Diag(D.getIdentifierLoc(), diag::err_destructor_return_type)
<< SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
<< SourceRange(D.getIdentifierLoc());
else if (unsigned TypeQuals = D.getDeclSpec().getTypeQualifiers()) {
diagnoseIgnoredQualifiers(diag::err_destructor_return_type, TypeQuals,
SourceLocation(),
D.getDeclSpec().getConstSpecLoc(),
D.getDeclSpec().getVolatileSpecLoc(),
D.getDeclSpec().getRestrictSpecLoc(),
D.getDeclSpec().getAtomicSpecLoc());
D.setInvalidType();
}
}
DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
if (FTI.TypeQuals != 0 && !D.isInvalidType()) {
if (FTI.TypeQuals & Qualifiers::Const)
Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor)
<< "const" << SourceRange(D.getIdentifierLoc());
if (FTI.TypeQuals & Qualifiers::Volatile)
Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor)
<< "volatile" << SourceRange(D.getIdentifierLoc());
if (FTI.TypeQuals & Qualifiers::Restrict)
Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor)
<< "restrict" << SourceRange(D.getIdentifierLoc());
D.setInvalidType();
}
// C++0x [class.dtor]p2:
// A destructor shall not be declared with a ref-qualifier.
if (FTI.hasRefQualifier()) {
Diag(FTI.getRefQualifierLoc(), diag::err_ref_qualifier_destructor)
<< FTI.RefQualifierIsLValueRef
<< FixItHint::CreateRemoval(FTI.getRefQualifierLoc());
D.setInvalidType();
}
// Make sure we don't have any parameters.
if (FTIHasNonVoidParameters(FTI)) {
Diag(D.getIdentifierLoc(), diag::err_destructor_with_params);
// Delete the parameters.
FTI.freeParams();
D.setInvalidType();
}
// Make sure the destructor isn't variadic.
if (FTI.isVariadic) {
Diag(D.getIdentifierLoc(), diag::err_destructor_variadic);
D.setInvalidType();
}
// Rebuild the function type "R" without any type qualifiers or
// parameters (in case any of the errors above fired) and with
// "void" as the return type, since destructors don't have return
// types.
if (!D.isInvalidType())
return R;
const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
EPI.Variadic = false;
EPI.TypeQuals = 0;
EPI.RefQualifier = RQ_None;
return Context.getFunctionType(Context.VoidTy, None, EPI);
}
/// CheckConversionDeclarator - Called by ActOnDeclarator to check the
/// well-formednes of the conversion function declarator @p D with
/// type @p R. If there are any errors in the declarator, this routine
/// will emit diagnostics and return true. Otherwise, it will return
/// false. Either way, the type @p R will be updated to reflect a
/// well-formed type for the conversion operator.
void Sema::CheckConversionDeclarator(Declarator &D, QualType &R,
StorageClass& SC) {
// C++ [class.conv.fct]p1:
// Neither parameter types nor return type can be specified. The
// type of a conversion function (8.3.5) is "function taking no
// parameter returning conversion-type-id."
if (SC == SC_Static) {
if (!D.isInvalidType())
Diag(D.getIdentifierLoc(), diag::err_conv_function_not_member)
<< SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
<< D.getName().getSourceRange();
D.setInvalidType();
SC = SC_None;
}
QualType ConvType = GetTypeFromParser(D.getName().ConversionFunctionId);
if (D.getDeclSpec().hasTypeSpecifier() && !D.isInvalidType()) {
// Conversion functions don't have return types, but the parser will
// happily parse something like:
//
// class X {
// float operator bool();
// };
//
// The return type will be changed later anyway.
Diag(D.getIdentifierLoc(), diag::err_conv_function_return_type)
<< SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
<< SourceRange(D.getIdentifierLoc());
D.setInvalidType();
}
const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
// Make sure we don't have any parameters.
if (Proto->getNumParams() > 0) {
Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params);
// Delete the parameters.
D.getFunctionTypeInfo().freeParams();
D.setInvalidType();
} else if (Proto->isVariadic()) {
Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic);
D.setInvalidType();
}
// Diagnose "&operator bool()" and other such nonsense. This
// is actually a gcc extension which we don't support.
if (Proto->getReturnType() != ConvType) {
Diag(D.getIdentifierLoc(), diag::err_conv_function_with_complex_decl)
<< Proto->getReturnType();
D.setInvalidType();
ConvType = Proto->getReturnType();
}
// C++ [class.conv.fct]p4:
// The conversion-type-id shall not represent a function type nor
// an array type.
if (ConvType->isArrayType()) {
Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array);
ConvType = Context.getPointerType(ConvType);
D.setInvalidType();
} else if (ConvType->isFunctionType()) {
Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function);
ConvType = Context.getPointerType(ConvType);
D.setInvalidType();
}
// Rebuild the function type "R" without any parameters (in case any
// of the errors above fired) and with the conversion type as the
// return type.
if (D.isInvalidType())
R = Context.getFunctionType(ConvType, None, Proto->getExtProtoInfo());
// C++0x explicit conversion operators.
if (D.getDeclSpec().isExplicitSpecified())
Diag(D.getDeclSpec().getExplicitSpecLoc(),
getLangOpts().CPlusPlus11 ?
diag::warn_cxx98_compat_explicit_conversion_functions :
diag::ext_explicit_conversion_functions)
<< SourceRange(D.getDeclSpec().getExplicitSpecLoc());
}
/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete
/// the declaration of the given C++ conversion function. This routine
/// is responsible for recording the conversion function in the C++
/// class, if possible.
Decl *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) {
assert(Conversion && "Expected to receive a conversion function declaration");
CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Conversion->getDeclContext());
// Make sure we aren't redeclaring the conversion function.
QualType ConvType = Context.getCanonicalType(Conversion->getConversionType());
// C++ [class.conv.fct]p1:
// [...] A conversion function is never used to convert a
// (possibly cv-qualified) object to the (possibly cv-qualified)
// same object type (or a reference to it), to a (possibly
// cv-qualified) base class of that type (or a reference to it),
// or to (possibly cv-qualified) void.
// FIXME: Suppress this warning if the conversion function ends up being a
// virtual function that overrides a virtual function in a base class.
QualType ClassType
= Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
if (const ReferenceType *ConvTypeRef = ConvType->getAs<ReferenceType>())
ConvType = ConvTypeRef->getPointeeType();
if (Conversion->getTemplateSpecializationKind() != TSK_Undeclared &&
Conversion->getTemplateSpecializationKind() != TSK_ExplicitSpecialization)
/* Suppress diagnostics for instantiations. */;
else if (ConvType->isRecordType()) {
ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType();
if (ConvType == ClassType)
Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used)
<< ClassType;
else if (IsDerivedFrom(ClassType, ConvType))
Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used)
<< ClassType << ConvType;
} else if (ConvType->isVoidType()) {
Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used)
<< ClassType << ConvType;
}
if (FunctionTemplateDecl *ConversionTemplate
= Conversion->getDescribedFunctionTemplate())
return ConversionTemplate;
return Conversion;
}
//===----------------------------------------------------------------------===//
// Namespace Handling
//===----------------------------------------------------------------------===//
/// \brief Diagnose a mismatch in 'inline' qualifiers when a namespace is
/// reopened.
static void DiagnoseNamespaceInlineMismatch(Sema &S, SourceLocation KeywordLoc,
SourceLocation Loc,
IdentifierInfo *II, bool *IsInline,
NamespaceDecl *PrevNS) {
assert(*IsInline != PrevNS->isInline());
// HACK: Work around a bug in libstdc++4.6's <atomic>, where
// std::__atomic[0,1,2] are defined as non-inline namespaces, then reopened as
// inline namespaces, with the intention of bringing names into namespace std.
//
// We support this just well enough to get that case working; this is not
// sufficient to support reopening namespaces as inline in general.
if (*IsInline && II && II->getName().startswith("__atomic") &&
S.getSourceManager().isInSystemHeader(Loc)) {
// Mark all prior declarations of the namespace as inline.
for (NamespaceDecl *NS = PrevNS->getMostRecentDecl(); NS;
NS = NS->getPreviousDecl())
NS->setInline(*IsInline);
// Patch up the lookup table for the containing namespace. This isn't really
// correct, but it's good enough for this particular case.
for (auto *I : PrevNS->decls())
if (auto *ND = dyn_cast<NamedDecl>(I))
PrevNS->getParent()->makeDeclVisibleInContext(ND);
return;
}
if (PrevNS->isInline())
// The user probably just forgot the 'inline', so suggest that it
// be added back.
S.Diag(Loc, diag::warn_inline_namespace_reopened_noninline)
<< FixItHint::CreateInsertion(KeywordLoc, "inline ");
else
S.Diag(Loc, diag::err_inline_namespace_mismatch) << *IsInline;
S.Diag(PrevNS->getLocation(), diag::note_previous_definition);
*IsInline = PrevNS->isInline();
}
/// ActOnStartNamespaceDef - This is called at the start of a namespace
/// definition.
Decl *Sema::ActOnStartNamespaceDef(Scope *NamespcScope,
SourceLocation InlineLoc,
SourceLocation NamespaceLoc,
SourceLocation IdentLoc,
IdentifierInfo *II,
SourceLocation LBrace,
AttributeList *AttrList) {
SourceLocation StartLoc = InlineLoc.isValid() ? InlineLoc : NamespaceLoc;
// For anonymous namespace, take the location of the left brace.
SourceLocation Loc = II ? IdentLoc : LBrace;
bool IsInline = InlineLoc.isValid();
bool IsInvalid = false;
bool IsStd = false;
bool AddToKnown = false;
Scope *DeclRegionScope = NamespcScope->getParent();
NamespaceDecl *PrevNS = nullptr;
if (II) {
// C++ [namespace.def]p2:
// The identifier in an original-namespace-definition shall not
// have been previously defined in the declarative region in
// which the original-namespace-definition appears. The
// identifier in an original-namespace-definition is the name of
// the namespace. Subsequently in that declarative region, it is
// treated as an original-namespace-name.
//
// Since namespace names are unique in their scope, and we don't
// look through using directives, just look for any ordinary names.
const unsigned IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Member |
Decl::IDNS_Type | Decl::IDNS_Using | Decl::IDNS_Tag |
Decl::IDNS_Namespace;
NamedDecl *PrevDecl = nullptr;
DeclContext::lookup_result R = CurContext->getRedeclContext()->lookup(II);
for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E;
++I) {
if ((*I)->getIdentifierNamespace() & IDNS) {
PrevDecl = *I;
break;
}
}
PrevNS = dyn_cast_or_null<NamespaceDecl>(PrevDecl);
if (PrevNS) {
// This is an extended namespace definition.
if (IsInline != PrevNS->isInline())
DiagnoseNamespaceInlineMismatch(*this, NamespaceLoc, Loc, II,
&IsInline, PrevNS);
} else if (PrevDecl) {
// This is an invalid name redefinition.
Diag(Loc, diag::err_redefinition_different_kind)
<< II;
Diag(PrevDecl->getLocation(), diag::note_previous_definition);
IsInvalid = true;
// Continue on to push Namespc as current DeclContext and return it.
} else if (II->isStr("std") &&
CurContext->getRedeclContext()->isTranslationUnit()) {
// This is the first "real" definition of the namespace "std", so update
// our cache of the "std" namespace to point at this definition.
PrevNS = getStdNamespace();
IsStd = true;
AddToKnown = !IsInline;
} else {
// We've seen this namespace for the first time.
AddToKnown = !IsInline;
}
} else {
// Anonymous namespaces.
// Determine whether the parent already has an anonymous namespace.
DeclContext *Parent = CurContext->getRedeclContext();
if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(Parent)) {
PrevNS = TU->getAnonymousNamespace();
} else {
NamespaceDecl *ND = cast<NamespaceDecl>(Parent);
PrevNS = ND->getAnonymousNamespace();
}
if (PrevNS && IsInline != PrevNS->isInline())
DiagnoseNamespaceInlineMismatch(*this, NamespaceLoc, NamespaceLoc, II,
&IsInline, PrevNS);
}
NamespaceDecl *Namespc = NamespaceDecl::Create(Context, CurContext, IsInline,
StartLoc, Loc, II, PrevNS);
if (IsInvalid)
Namespc->setInvalidDecl();
ProcessDeclAttributeList(DeclRegionScope, Namespc, AttrList);
// FIXME: Should we be merging attributes?
if (const VisibilityAttr *Attr = Namespc->getAttr<VisibilityAttr>())
PushNamespaceVisibilityAttr(Attr, Loc);
if (IsStd)
StdNamespace = Namespc;
if (AddToKnown)
KnownNamespaces[Namespc] = false;
if (II) {
PushOnScopeChains(Namespc, DeclRegionScope);
} else {
// Link the anonymous namespace into its parent.
DeclContext *Parent = CurContext->getRedeclContext();
if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(Parent)) {
TU->setAnonymousNamespace(Namespc);
} else {
cast<NamespaceDecl>(Parent)->setAnonymousNamespace(Namespc);
}
CurContext->addDecl(Namespc);
// C++ [namespace.unnamed]p1. An unnamed-namespace-definition
// behaves as if it were replaced by
// namespace unique { /* empty body */ }
// using namespace unique;
// namespace unique { namespace-body }
// where all occurrences of 'unique' in a translation unit are
// replaced by the same identifier and this identifier differs
// from all other identifiers in the entire program.
// We just create the namespace with an empty name and then add an
// implicit using declaration, just like the standard suggests.
//
// CodeGen enforces the "universally unique" aspect by giving all
// declarations semantically contained within an anonymous
// namespace internal linkage.
if (!PrevNS) {
UsingDirectiveDecl* UD
= UsingDirectiveDecl::Create(Context, Parent,
/* 'using' */ LBrace,
/* 'namespace' */ SourceLocation(),
/* qualifier */ NestedNameSpecifierLoc(),
/* identifier */ SourceLocation(),
Namespc,
/* Ancestor */ Parent);
UD->setImplicit();
Parent->addDecl(UD);
}
}
ActOnDocumentableDecl(Namespc);
// Although we could have an invalid decl (i.e. the namespace name is a
// redefinition), push it as current DeclContext and try to continue parsing.
// FIXME: We should be able to push Namespc here, so that the each DeclContext
// for the namespace has the declarations that showed up in that particular
// namespace definition.
PushDeclContext(NamespcScope, Namespc);
return Namespc;
}
/// getNamespaceDecl - Returns the namespace a decl represents. If the decl
/// is a namespace alias, returns the namespace it points to.
static inline NamespaceDecl *getNamespaceDecl(NamedDecl *D) {
if (NamespaceAliasDecl *AD = dyn_cast_or_null<NamespaceAliasDecl>(D))
return AD->getNamespace();
return dyn_cast_or_null<NamespaceDecl>(D);
}
/// ActOnFinishNamespaceDef - This callback is called after a namespace is
/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef.
void Sema::ActOnFinishNamespaceDef(Decl *Dcl, SourceLocation RBrace) {
NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl);
assert(Namespc && "Invalid parameter, expected NamespaceDecl");
Namespc->setRBraceLoc(RBrace);
PopDeclContext();
if (Namespc->hasAttr<VisibilityAttr>())
PopPragmaVisibility(true, RBrace);
}
CXXRecordDecl *Sema::getStdBadAlloc() const {
return cast_or_null<CXXRecordDecl>(
StdBadAlloc.get(Context.getExternalSource()));
}
NamespaceDecl *Sema::getStdNamespace() const {
return cast_or_null<NamespaceDecl>(
StdNamespace.get(Context.getExternalSource()));
}
/// \brief Retrieve the special "std" namespace, which may require us to
/// implicitly define the namespace.
NamespaceDecl *Sema::getOrCreateStdNamespace() {
if (!StdNamespace) {
// The "std" namespace has not yet been defined, so build one implicitly.
StdNamespace = NamespaceDecl::Create(Context,
Context.getTranslationUnitDecl(),
/*Inline=*/false,
SourceLocation(), SourceLocation(),
&PP.getIdentifierTable().get("std"),
/*PrevDecl=*/nullptr);
getStdNamespace()->setImplicit(true);
}
return getStdNamespace();
}
bool Sema::isStdInitializerList(QualType Ty, QualType *Element) {
assert(getLangOpts().CPlusPlus &&
"Looking for std::initializer_list outside of C++.");
// We're looking for implicit instantiations of
// template <typename E> class std::initializer_list.
if (!StdNamespace) // If we haven't seen namespace std yet, this can't be it.
return false;
ClassTemplateDecl *Template = nullptr;
const TemplateArgument *Arguments = nullptr;
if (const RecordType *RT = Ty->getAs<RecordType>()) {
ClassTemplateSpecializationDecl *Specialization =
dyn_cast<ClassTemplateSpecializationDecl>(RT->getDecl());
if (!Specialization)
return false;
Template = Specialization->getSpecializedTemplate();
Arguments = Specialization->getTemplateArgs().data();
} else if (const TemplateSpecializationType *TST =
Ty->getAs<TemplateSpecializationType>()) {
Template = dyn_cast_or_null<ClassTemplateDecl>(
TST->getTemplateName().getAsTemplateDecl());
Arguments = TST->getArgs();
}
if (!Template)
return false;
if (!StdInitializerList) {
// Haven't recognized std::initializer_list yet, maybe this is it.
CXXRecordDecl *TemplateClass = Template->getTemplatedDecl();
if (TemplateClass->getIdentifier() !=
&PP.getIdentifierTable().get("initializer_list") ||
!getStdNamespace()->InEnclosingNamespaceSetOf(
TemplateClass->getDeclContext()))
return false;
// This is a template called std::initializer_list, but is it the right
// template?
TemplateParameterList *Params = Template->getTemplateParameters();
if (Params->getMinRequiredArguments() != 1)
return false;
if (!isa<TemplateTypeParmDecl>(Params->getParam(0)))
return false;
// It's the right template.
StdInitializerList = Template;
}
if (Template != StdInitializerList)
return false;
// This is an instance of std::initializer_list. Find the argument type.
if (Element)
*Element = Arguments[0].getAsType();
return true;
}
static ClassTemplateDecl *LookupStdInitializerList(Sema &S, SourceLocation Loc){
NamespaceDecl *Std = S.getStdNamespace();
if (!Std) {
S.Diag(Loc, diag::err_implied_std_initializer_list_not_found);
return nullptr;
}
LookupResult Result(S, &S.PP.getIdentifierTable().get("initializer_list"),
Loc, Sema::LookupOrdinaryName);
if (!S.LookupQualifiedName(Result, Std)) {
S.Diag(Loc, diag::err_implied_std_initializer_list_not_found);
return nullptr;
}
ClassTemplateDecl *Template = Result.getAsSingle<ClassTemplateDecl>();
if (!Template) {
Result.suppressDiagnostics();
// We found something weird. Complain about the first thing we found.
NamedDecl *Found = *Result.begin();
S.Diag(Found->getLocation(), diag::err_malformed_std_initializer_list);
return nullptr;
}
// We found some template called std::initializer_list. Now verify that it's
// correct.
TemplateParameterList *Params = Template->getTemplateParameters();
if (Params->getMinRequiredArguments() != 1 ||
!isa<TemplateTypeParmDecl>(Params->getParam(0))) {
S.Diag(Template->getLocation(), diag::err_malformed_std_initializer_list);
return nullptr;
}
return Template;
}
QualType Sema::BuildStdInitializerList(QualType Element, SourceLocation Loc) {
if (!StdInitializerList) {
StdInitializerList = LookupStdInitializerList(*this, Loc);
if (!StdInitializerList)
return QualType();
}
TemplateArgumentListInfo Args(Loc, Loc);
Args.addArgument(TemplateArgumentLoc(TemplateArgument(Element),
Context.getTrivialTypeSourceInfo(Element,
Loc)));
return Context.getCanonicalType(
CheckTemplateIdType(TemplateName(StdInitializerList), Loc, Args));
}
bool Sema::isInitListConstructor(const CXXConstructorDecl* Ctor) {
// C++ [dcl.init.list]p2:
// A constructor is an initializer-list constructor if its first parameter
// is of type std::initializer_list<E> or reference to possibly cv-qualified
// std::initializer_list<E> for some type E, and either there are no other
// parameters or else all other parameters have default arguments.
if (Ctor->getNumParams() < 1 ||
(Ctor->getNumParams() > 1 && !Ctor->getParamDecl(1)->hasDefaultArg()))
return false;
QualType ArgType = Ctor->getParamDecl(0)->getType();
if (const ReferenceType *RT = ArgType->getAs<ReferenceType>())
ArgType = RT->getPointeeType().getUnqualifiedType();
return isStdInitializerList(ArgType, nullptr);
}
/// \brief Determine whether a using statement is in a context where it will be
/// apply in all contexts.
static bool IsUsingDirectiveInToplevelContext(DeclContext *CurContext) {
switch (CurContext->getDeclKind()) {
case Decl::TranslationUnit:
return true;
case Decl::LinkageSpec:
return IsUsingDirectiveInToplevelContext(CurContext->getParent());
default:
return false;
}
}
namespace {
// Callback to only accept typo corrections that are namespaces.
class NamespaceValidatorCCC : public CorrectionCandidateCallback {
public:
bool ValidateCandidate(const TypoCorrection &candidate) override {
if (NamedDecl *ND = candidate.getCorrectionDecl())
return isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND);
return false;
}
};
}
static bool TryNamespaceTypoCorrection(Sema &S, LookupResult &R, Scope *Sc,
CXXScopeSpec &SS,
SourceLocation IdentLoc,
IdentifierInfo *Ident) {
NamespaceValidatorCCC Validator;
R.clear();
if (TypoCorrection Corrected = S.CorrectTypo(R.getLookupNameInfo(),
R.getLookupKind(), Sc, &SS,
Validator,
Sema::CTK_ErrorRecovery)) {
if (DeclContext *DC = S.computeDeclContext(SS, false)) {
std::string CorrectedStr(Corrected.getAsString(S.getLangOpts()));
bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
Ident->getName().equals(CorrectedStr);
S.diagnoseTypo(Corrected,
S.PDiag(diag::err_using_directive_member_suggest)
<< Ident << DC << DroppedSpecifier << SS.getRange(),
S.PDiag(diag::note_namespace_defined_here));
} else {
S.diagnoseTypo(Corrected,
S.PDiag(diag::err_using_directive_suggest) << Ident,
S.PDiag(diag::note_namespace_defined_here));
}
R.addDecl(Corrected.getCorrectionDecl());
return true;
}
return false;
}
Decl *Sema::ActOnUsingDirective(Scope *S,
SourceLocation UsingLoc,
SourceLocation NamespcLoc,
CXXScopeSpec &SS,
SourceLocation IdentLoc,
IdentifierInfo *NamespcName,
AttributeList *AttrList) {
assert(!SS.isInvalid() && "Invalid CXXScopeSpec.");
assert(NamespcName && "Invalid NamespcName.");
assert(IdentLoc.isValid() && "Invalid NamespceName location.");
// This can only happen along a recovery path.
while (S->getFlags() & Scope::TemplateParamScope)
S = S->getParent();
assert(S->getFlags() & Scope::DeclScope && "Invalid Scope.");
UsingDirectiveDecl *UDir = nullptr;
NestedNameSpecifier *Qualifier = nullptr;
if (SS.isSet())
Qualifier = SS.getScopeRep();
// Lookup namespace name.
LookupResult R(*this, NamespcName, IdentLoc, LookupNamespaceName);
LookupParsedName(R, S, &SS);
if (R.isAmbiguous())
return nullptr;
if (R.empty()) {
R.clear();
// Allow "using namespace std;" or "using namespace ::std;" even if
// "std" hasn't been defined yet, for GCC compatibility.
if ((!Qualifier || Qualifier->getKind() == NestedNameSpecifier::Global) &&
NamespcName->isStr("std")) {
Diag(IdentLoc, diag::ext_using_undefined_std);
R.addDecl(getOrCreateStdNamespace());
R.resolveKind();
}
// Otherwise, attempt typo correction.
else TryNamespaceTypoCorrection(*this, R, S, SS, IdentLoc, NamespcName);
}
if (!R.empty()) {
NamedDecl *Named = R.getFoundDecl();
assert((isa<NamespaceDecl>(Named) || isa<NamespaceAliasDecl>(Named))
&& "expected namespace decl");
// C++ [namespace.udir]p1:
// A using-directive specifies that the names in the nominated
// namespace can be used in the scope in which the
// using-directive appears after the using-directive. During
// unqualified name lookup (3.4.1), the names appear as if they
// were declared in the nearest enclosing namespace which
// contains both the using-directive and the nominated
// namespace. [Note: in this context, "contains" means "contains
// directly or indirectly". ]
// Find enclosing context containing both using-directive and
// nominated namespace.
NamespaceDecl *NS = getNamespaceDecl(Named);
DeclContext *CommonAncestor = cast<DeclContext>(NS);
while (CommonAncestor && !CommonAncestor->Encloses(CurContext))
CommonAncestor = CommonAncestor->getParent();
UDir = UsingDirectiveDecl::Create(Context, CurContext, UsingLoc, NamespcLoc,
SS.getWithLocInContext(Context),
IdentLoc, Named, CommonAncestor);
if (IsUsingDirectiveInToplevelContext(CurContext) &&
!SourceMgr.isInMainFile(SourceMgr.getExpansionLoc(IdentLoc))) {
Diag(IdentLoc, diag::warn_using_directive_in_header);
}
PushUsingDirective(S, UDir);
} else {
Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange();
}
if (UDir)
ProcessDeclAttributeList(S, UDir, AttrList);
return UDir;
}
void Sema::PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir) {
// If the scope has an associated entity and the using directive is at
// namespace or translation unit scope, add the UsingDirectiveDecl into
// its lookup structure so qualified name lookup can find it.
DeclContext *Ctx = S->getEntity();
if (Ctx && !Ctx->isFunctionOrMethod())
Ctx->addDecl(UDir);
else
// Otherwise, it is at block scope. The using-directives will affect lookup
// only to the end of the scope.
S->PushUsingDirective(UDir);
}
Decl *Sema::ActOnUsingDeclaration(Scope *S,
AccessSpecifier AS,
bool HasUsingKeyword,
SourceLocation UsingLoc,
CXXScopeSpec &SS,
UnqualifiedId &Name,
AttributeList *AttrList,
bool HasTypenameKeyword,
SourceLocation TypenameLoc) {
assert(S->getFlags() & Scope::DeclScope && "Invalid Scope.");
switch (Name.getKind()) {
case UnqualifiedId::IK_ImplicitSelfParam:
case UnqualifiedId::IK_Identifier:
case UnqualifiedId::IK_OperatorFunctionId:
case UnqualifiedId::IK_LiteralOperatorId:
case UnqualifiedId::IK_ConversionFunctionId:
break;
case UnqualifiedId::IK_ConstructorName:
case UnqualifiedId::IK_ConstructorTemplateId:
// C++11 inheriting constructors.
Diag(Name.getLocStart(),
getLangOpts().CPlusPlus11 ?
diag::warn_cxx98_compat_using_decl_constructor :
diag::err_using_decl_constructor)
<< SS.getRange();
if (getLangOpts().CPlusPlus11) break;
return nullptr;
case UnqualifiedId::IK_DestructorName:
Diag(Name.getLocStart(), diag::err_using_decl_destructor)
<< SS.getRange();
return nullptr;
case UnqualifiedId::IK_TemplateId:
Diag(Name.getLocStart(), diag::err_using_decl_template_id)
<< SourceRange(Name.TemplateId->LAngleLoc, Name.TemplateId->RAngleLoc);
return nullptr;
}
DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
DeclarationName TargetName = TargetNameInfo.getName();
if (!TargetName)
return nullptr;
// Warn about access declarations.
if (!HasUsingKeyword) {
Diag(Name.getLocStart(),
getLangOpts().CPlusPlus11 ? diag::err_access_decl
: diag::warn_access_decl_deprecated)
<< FixItHint::CreateInsertion(SS.getRange().getBegin(), "using ");
}
if (DiagnoseUnexpandedParameterPack(SS, UPPC_UsingDeclaration) ||
DiagnoseUnexpandedParameterPack(TargetNameInfo, UPPC_UsingDeclaration))
return nullptr;
NamedDecl *UD = BuildUsingDeclaration(S, AS, UsingLoc, SS,
TargetNameInfo, AttrList,
/* IsInstantiation */ false,
HasTypenameKeyword, TypenameLoc);
if (UD)
PushOnScopeChains(UD, S, /*AddToContext*/ false);
return UD;
}
/// \brief Determine whether a using declaration considers the given
/// declarations as "equivalent", e.g., if they are redeclarations of
/// the same entity or are both typedefs of the same type.
static bool
IsEquivalentForUsingDecl(ASTContext &Context, NamedDecl *D1, NamedDecl *D2) {
if (D1->getCanonicalDecl() == D2->getCanonicalDecl())
return true;
if (TypedefNameDecl *TD1 = dyn_cast<TypedefNameDecl>(D1))
if (TypedefNameDecl *TD2 = dyn_cast<TypedefNameDecl>(D2))
return Context.hasSameType(TD1->getUnderlyingType(),
TD2->getUnderlyingType());
return false;
}
/// Determines whether to create a using shadow decl for a particular
/// decl, given the set of decls existing prior to this using lookup.
bool Sema::CheckUsingShadowDecl(UsingDecl *Using, NamedDecl *Orig,
const LookupResult &Previous,
UsingShadowDecl *&PrevShadow) {
// Diagnose finding a decl which is not from a base class of the
// current class. We do this now because there are cases where this
// function will silently decide not to build a shadow decl, which
// will pre-empt further diagnostics.
//
// We don't need to do this in C++0x because we do the check once on
// the qualifier.
//
// FIXME: diagnose the following if we care enough:
// struct A { int foo; };
// struct B : A { using A::foo; };
// template <class T> struct C : A {};
// template <class T> struct D : C<T> { using B::foo; } // <---
// This is invalid (during instantiation) in C++03 because B::foo
// resolves to the using decl in B, which is not a base class of D<T>.
// We can't diagnose it immediately because C<T> is an unknown
// specialization. The UsingShadowDecl in D<T> then points directly
// to A::foo, which will look well-formed when we instantiate.
// The right solution is to not collapse the shadow-decl chain.
if (!getLangOpts().CPlusPlus11 && CurContext->isRecord()) {
DeclContext *OrigDC = Orig->getDeclContext();
// Handle enums and anonymous structs.
if (isa<EnumDecl>(OrigDC)) OrigDC = OrigDC->getParent();
CXXRecordDecl *OrigRec = cast<CXXRecordDecl>(OrigDC);
while (OrigRec->isAnonymousStructOrUnion())
OrigRec = cast<CXXRecordDecl>(OrigRec->getDeclContext());
if (cast<CXXRecordDecl>(CurContext)->isProvablyNotDerivedFrom(OrigRec)) {
if (OrigDC == CurContext) {
Diag(Using->getLocation(),
diag::err_using_decl_nested_name_specifier_is_current_class)
<< Using->getQualifierLoc().getSourceRange();
Diag(Orig->getLocation(), diag::note_using_decl_target);
return true;
}
Diag(Using->getQualifierLoc().getBeginLoc(),
diag::err_using_decl_nested_name_specifier_is_not_base_class)
<< Using->getQualifier()
<< cast<CXXRecordDecl>(CurContext)
<< Using->getQualifierLoc().getSourceRange();
Diag(Orig->getLocation(), diag::note_using_decl_target);
return true;
}
}
if (Previous.empty()) return false;
NamedDecl *Target = Orig;
if (isa<UsingShadowDecl>(Target))
Target = cast<UsingShadowDecl>(Target)->getTargetDecl();
// If the target happens to be one of the previous declarations, we
// don't have a conflict.
//
// FIXME: but we might be increasing its access, in which case we
// should redeclare it.
NamedDecl *NonTag = nullptr, *Tag = nullptr;
bool FoundEquivalentDecl = false;
for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
I != E; ++I) {
NamedDecl *D = (*I)->getUnderlyingDecl();
if (IsEquivalentForUsingDecl(Context, D, Target)) {
if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(*I))
PrevShadow = Shadow;
FoundEquivalentDecl = true;
}
(isa<TagDecl>(D) ? Tag : NonTag) = D;
}
if (FoundEquivalentDecl)
return false;
if (FunctionDecl *FD = Target->getAsFunction()) {
NamedDecl *OldDecl = nullptr;
switch (CheckOverload(nullptr, FD, Previous, OldDecl,
/*IsForUsingDecl*/ true)) {
case Ovl_Overload:
return false;
case Ovl_NonFunction:
Diag(Using->getLocation(), diag::err_using_decl_conflict);
break;
// We found a decl with the exact signature.
case Ovl_Match:
// If we're in a record, we want to hide the target, so we
// return true (without a diagnostic) to tell the caller not to
// build a shadow decl.
if (CurContext->isRecord())
return true;
// If we're not in a record, this is an error.
Diag(Using->getLocation(), diag::err_using_decl_conflict);
break;
}
Diag(Target->getLocation(), diag::note_using_decl_target);
Diag(OldDecl->getLocation(), diag::note_using_decl_conflict);
return true;
}
// Target is not a function.
if (isa<TagDecl>(Target)) {
// No conflict between a tag and a non-tag.
if (!Tag) return false;
Diag(Using->getLocation(), diag::err_using_decl_conflict);
Diag(Target->getLocation(), diag::note_using_decl_target);
Diag(Tag->getLocation(), diag::note_using_decl_conflict);
return true;
}
// No conflict between a tag and a non-tag.
if (!NonTag) return false;
Diag(Using->getLocation(), diag::err_using_decl_conflict);
Diag(Target->getLocation(), diag::note_using_decl_target);
Diag(NonTag->getLocation(), diag::note_using_decl_conflict);
return true;
}
/// Builds a shadow declaration corresponding to a 'using' declaration.
UsingShadowDecl *Sema::BuildUsingShadowDecl(Scope *S,
UsingDecl *UD,
NamedDecl *Orig,
UsingShadowDecl *PrevDecl) {
// If we resolved to another shadow declaration, just coalesce them.
NamedDecl *Target = Orig;
if (isa<UsingShadowDecl>(Target)) {
Target = cast<UsingShadowDecl>(Target)->getTargetDecl();
assert(!isa<UsingShadowDecl>(Target) && "nested shadow declaration");
}
UsingShadowDecl *Shadow
= UsingShadowDecl::Create(Context, CurContext,
UD->getLocation(), UD, Target);
UD->addShadowDecl(Shadow);
Shadow->setAccess(UD->getAccess());
if (Orig->isInvalidDecl() || UD->isInvalidDecl())
Shadow->setInvalidDecl();
Shadow->setPreviousDecl(PrevDecl);
if (S)
PushOnScopeChains(Shadow, S);
else
CurContext->addDecl(Shadow);
return Shadow;
}
/// Hides a using shadow declaration. This is required by the current
/// using-decl implementation when a resolvable using declaration in a
/// class is followed by a declaration which would hide or override
/// one or more of the using decl's targets; for example:
///
/// struct Base { void foo(int); };
/// struct Derived : Base {
/// using Base::foo;
/// void foo(int);
/// };
///
/// The governing language is C++03 [namespace.udecl]p12:
///
/// When a using-declaration brings names from a base class into a
/// derived class scope, member functions in the derived class
/// override and/or hide member functions with the same name and
/// parameter types in a base class (rather than conflicting).
///
/// There are two ways to implement this:
/// (1) optimistically create shadow decls when they're not hidden
/// by existing declarations, or
/// (2) don't create any shadow decls (or at least don't make them
/// visible) until we've fully parsed/instantiated the class.
/// The problem with (1) is that we might have to retroactively remove
/// a shadow decl, which requires several O(n) operations because the
/// decl structures are (very reasonably) not designed for removal.
/// (2) avoids this but is very fiddly and phase-dependent.
void Sema::HideUsingShadowDecl(Scope *S, UsingShadowDecl *Shadow) {
if (Shadow->getDeclName().getNameKind() ==
DeclarationName::CXXConversionFunctionName)
cast<CXXRecordDecl>(Shadow->getDeclContext())->removeConversion(Shadow);
// Remove it from the DeclContext...
Shadow->getDeclContext()->removeDecl(Shadow);
// ...and the scope, if applicable...
if (S) {
S->RemoveDecl(Shadow);
IdResolver.RemoveDecl(Shadow);
}
// ...and the using decl.
Shadow->getUsingDecl()->removeShadowDecl(Shadow);
// TODO: complain somehow if Shadow was used. It shouldn't
// be possible for this to happen, because...?
}
/// Find the base specifier for a base class with the given type.
static CXXBaseSpecifier *findDirectBaseWithType(CXXRecordDecl *Derived,
QualType DesiredBase,
bool &AnyDependentBases) {
// Check whether the named type is a direct base class.
CanQualType CanonicalDesiredBase = DesiredBase->getCanonicalTypeUnqualified();
for (auto &Base : Derived->bases()) {
CanQualType BaseType = Base.getType()->getCanonicalTypeUnqualified();
if (CanonicalDesiredBase == BaseType)
return &Base;
if (BaseType->isDependentType())
AnyDependentBases = true;
}
return nullptr;
}
namespace {
class UsingValidatorCCC : public CorrectionCandidateCallback {
public:
UsingValidatorCCC(bool HasTypenameKeyword, bool IsInstantiation,
NestedNameSpecifier *NNS, CXXRecordDecl *RequireMemberOf)
: HasTypenameKeyword(HasTypenameKeyword),
IsInstantiation(IsInstantiation), OldNNS(NNS),
RequireMemberOf(RequireMemberOf) {}
bool ValidateCandidate(const TypoCorrection &Candidate) override {
NamedDecl *ND = Candidate.getCorrectionDecl();
// Keywords are not valid here.
if (!ND || isa<NamespaceDecl>(ND))
return false;
// Completely unqualified names are invalid for a 'using' declaration.
if (Candidate.WillReplaceSpecifier() && !Candidate.getCorrectionSpecifier())
return false;
if (RequireMemberOf) {
auto *FoundRecord = dyn_cast<CXXRecordDecl>(ND);
if (FoundRecord && FoundRecord->isInjectedClassName()) {
// No-one ever wants a using-declaration to name an injected-class-name
// of a base class, unless they're declaring an inheriting constructor.
ASTContext &Ctx = ND->getASTContext();
if (!Ctx.getLangOpts().CPlusPlus11)
return false;
QualType FoundType = Ctx.getRecordType(FoundRecord);
// Check that the injected-class-name is named as a member of its own
// type; we don't want to suggest 'using Derived::Base;', since that
// means something else.
NestedNameSpecifier *Specifier =
Candidate.WillReplaceSpecifier()
? Candidate.getCorrectionSpecifier()
: OldNNS;
if (!Specifier->getAsType() ||
!Ctx.hasSameType(QualType(Specifier->getAsType(), 0), FoundType))
return false;
// Check that this inheriting constructor declaration actually names a
// direct base class of the current class.
bool AnyDependentBases = false;
if (!findDirectBaseWithType(RequireMemberOf,
Ctx.getRecordType(FoundRecord),
AnyDependentBases) &&
!AnyDependentBases)
return false;
} else {
auto *RD = dyn_cast<CXXRecordDecl>(ND->getDeclContext());
if (!RD || RequireMemberOf->isProvablyNotDerivedFrom(RD))
return false;
// FIXME: Check that the base class member is accessible?
}
}
if (isa<TypeDecl>(ND))
return HasTypenameKeyword || !IsInstantiation;
return !HasTypenameKeyword;
}
private:
bool HasTypenameKeyword;
bool IsInstantiation;
NestedNameSpecifier *OldNNS;
CXXRecordDecl *RequireMemberOf;
};
} // end anonymous namespace
/// Builds a using declaration.
///
/// \param IsInstantiation - Whether this call arises from an
/// instantiation of an unresolved using declaration. We treat
/// the lookup differently for these declarations.
NamedDecl *Sema::BuildUsingDeclaration(Scope *S, AccessSpecifier AS,
SourceLocation UsingLoc,
CXXScopeSpec &SS,
DeclarationNameInfo NameInfo,
AttributeList *AttrList,
bool IsInstantiation,
bool HasTypenameKeyword,
SourceLocation TypenameLoc) {
assert(!SS.isInvalid() && "Invalid CXXScopeSpec.");
SourceLocation IdentLoc = NameInfo.getLoc();
assert(IdentLoc.isValid() && "Invalid TargetName location.");
// FIXME: We ignore attributes for now.
if (SS.isEmpty()) {
Diag(IdentLoc, diag::err_using_requires_qualname);
return nullptr;
}
// Do the redeclaration lookup in the current scope.
LookupResult Previous(*this, NameInfo, LookupUsingDeclName,
ForRedeclaration);
Previous.setHideTags(false);
if (S) {
LookupName(Previous, S);
// It is really dumb that we have to do this.
LookupResult::Filter F = Previous.makeFilter();
while (F.hasNext()) {
NamedDecl *D = F.next();
if (!isDeclInScope(D, CurContext, S))
F.erase();
// If we found a local extern declaration that's not ordinarily visible,
// and this declaration is being added to a non-block scope, ignore it.
// We're only checking for scope conflicts here, not also for violations
// of the linkage rules.
else if (!CurContext->isFunctionOrMethod() && D->isLocalExternDecl() &&
!(D->getIdentifierNamespace() & Decl::IDNS_Ordinary))
F.erase();
}
F.done();
} else {
assert(IsInstantiation && "no scope in non-instantiation");
assert(CurContext->isRecord() && "scope not record in instantiation");
LookupQualifiedName(Previous, CurContext);
}
// Check for invalid redeclarations.
if (CheckUsingDeclRedeclaration(UsingLoc, HasTypenameKeyword,
SS, IdentLoc, Previous))
return nullptr;
// Check for bad qualifiers.
if (CheckUsingDeclQualifier(UsingLoc, SS, NameInfo, IdentLoc))
return nullptr;
DeclContext *LookupContext = computeDeclContext(SS);
NamedDecl *D;
NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
if (!LookupContext) {
if (HasTypenameKeyword) {
// FIXME: not all declaration name kinds are legal here
D = UnresolvedUsingTypenameDecl::Create(Context, CurContext,
UsingLoc, TypenameLoc,
QualifierLoc,
IdentLoc, NameInfo.getName());
} else {
D = UnresolvedUsingValueDecl::Create(Context, CurContext, UsingLoc,
QualifierLoc, NameInfo);
}
D->setAccess(AS);
CurContext->addDecl(D);
return D;
}
auto Build = [&](bool Invalid) {
UsingDecl *UD =
UsingDecl::Create(Context, CurContext, UsingLoc, QualifierLoc, NameInfo,
HasTypenameKeyword);
UD->setAccess(AS);
CurContext->addDecl(UD);
UD->setInvalidDecl(Invalid);
return UD;
};
auto BuildInvalid = [&]{ return Build(true); };
auto BuildValid = [&]{ return Build(false); };
if (RequireCompleteDeclContext(SS, LookupContext))
return BuildInvalid();
// The normal rules do not apply to inheriting constructor declarations.
if (NameInfo.getName().getNameKind() == DeclarationName::CXXConstructorName) {
UsingDecl *UD = BuildValid();
CheckInheritingConstructorUsingDecl(UD);
return UD;
}
// Otherwise, look up the target name.
LookupResult R(*this, NameInfo, LookupOrdinaryName);
// Unlike most lookups, we don't always want to hide tag
// declarations: tag names are visible through the using declaration
// even if hidden by ordinary names, *except* in a dependent context
// where it's important for the sanity of two-phase lookup.
if (!IsInstantiation)
R.setHideTags(false);
// For the purposes of this lookup, we have a base object type
// equal to that of the current context.
if (CurContext->isRecord()) {
R.setBaseObjectType(
Context.getTypeDeclType(cast<CXXRecordDecl>(CurContext)));
}
LookupQualifiedName(R, LookupContext);
// Try to correct typos if possible.
if (R.empty()) {
UsingValidatorCCC CCC(HasTypenameKeyword, IsInstantiation, SS.getScopeRep(),
dyn_cast<CXXRecordDecl>(CurContext));
if (TypoCorrection Corrected = CorrectTypo(R.getLookupNameInfo(),
R.getLookupKind(), S, &SS, CCC,
CTK_ErrorRecovery)){
// We reject any correction for which ND would be NULL.
NamedDecl *ND = Corrected.getCorrectionDecl();
// We reject candidates where DroppedSpecifier == true, hence the
// literal '0' below.
diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
<< NameInfo.getName() << LookupContext << 0
<< SS.getRange());
// If we corrected to an inheriting constructor, handle it as one.
auto *RD = dyn_cast<CXXRecordDecl>(ND);
if (RD && RD->isInjectedClassName()) {
// Fix up the information we'll use to build the using declaration.
if (Corrected.WillReplaceSpecifier()) {
NestedNameSpecifierLocBuilder Builder;
Builder.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
QualifierLoc.getSourceRange());
QualifierLoc = Builder.getWithLocInContext(Context);
}
NameInfo.setName(Context.DeclarationNames.getCXXConstructorName(
Context.getCanonicalType(Context.getRecordType(RD))));
NameInfo.setNamedTypeInfo(nullptr);
// Build it and process it as an inheriting constructor.
UsingDecl *UD = BuildValid();
CheckInheritingConstructorUsingDecl(UD);
return UD;
}
// FIXME: Pick up all the declarations if we found an overloaded function.
R.setLookupName(Corrected.getCorrection());
R.addDecl(ND);
} else {
Diag(IdentLoc, diag::err_no_member)
<< NameInfo.getName() << LookupContext << SS.getRange();
return BuildInvalid();
}
}
if (R.isAmbiguous())
return BuildInvalid();
if (HasTypenameKeyword) {
// If we asked for a typename and got a non-type decl, error out.
if (!R.getAsSingle<TypeDecl>()) {
Diag(IdentLoc, diag::err_using_typename_non_type);
for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
Diag((*I)->getUnderlyingDecl()->getLocation(),
diag::note_using_decl_target);
return BuildInvalid();
}
} else {
// If we asked for a non-typename and we got a type, error out,
// but only if this is an instantiation of an unresolved using
// decl. Otherwise just silently find the type name.
if (IsInstantiation && R.getAsSingle<TypeDecl>()) {
Diag(IdentLoc, diag::err_using_dependent_value_is_type);
Diag(R.getFoundDecl()->getLocation(), diag::note_using_decl_target);
return BuildInvalid();
}
}
// C++0x N2914 [namespace.udecl]p6:
// A using-declaration shall not name a namespace.
if (R.getAsSingle<NamespaceDecl>()) {
Diag(IdentLoc, diag::err_using_decl_can_not_refer_to_namespace)
<< SS.getRange();
return BuildInvalid();
}
UsingDecl *UD = BuildValid();
for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
UsingShadowDecl *PrevDecl = nullptr;
if (!CheckUsingShadowDecl(UD, *I, Previous, PrevDecl))
BuildUsingShadowDecl(S, UD, *I, PrevDecl);
}
return UD;
}
/// Additional checks for a using declaration referring to a constructor name.
bool Sema::CheckInheritingConstructorUsingDecl(UsingDecl *UD) {
assert(!UD->hasTypename() && "expecting a constructor name");
const Type *SourceType = UD->getQualifier()->getAsType();
assert(SourceType &&
"Using decl naming constructor doesn't have type in scope spec.");
CXXRecordDecl *TargetClass = cast<CXXRecordDecl>(CurContext);
// Check whether the named type is a direct base class.
bool AnyDependentBases = false;
auto *Base = findDirectBaseWithType(TargetClass, QualType(SourceType, 0),
AnyDependentBases);
if (!Base && !AnyDependentBases) {
Diag(UD->getUsingLoc(),
diag::err_using_decl_constructor_not_in_direct_base)
<< UD->getNameInfo().getSourceRange()
<< QualType(SourceType, 0) << TargetClass;
UD->setInvalidDecl();
return true;
}
if (Base)
Base->setInheritConstructors();
return false;
}
/// Checks that the given using declaration is not an invalid
/// redeclaration. Note that this is checking only for the using decl
/// itself, not for any ill-formedness among the UsingShadowDecls.
bool Sema::CheckUsingDeclRedeclaration(SourceLocation UsingLoc,
bool HasTypenameKeyword,
const CXXScopeSpec &SS,
SourceLocation NameLoc,
const LookupResult &Prev) {
// C++03 [namespace.udecl]p8:
// C++0x [namespace.udecl]p10:
// A using-declaration is a declaration and can therefore be used
// repeatedly where (and only where) multiple declarations are
// allowed.
//
// That's in non-member contexts.
if (!CurContext->getRedeclContext()->isRecord())
return false;
NestedNameSpecifier *Qual = SS.getScopeRep();
for (LookupResult::iterator I = Prev.begin(), E = Prev.end(); I != E; ++I) {
NamedDecl *D = *I;
bool DTypename;
NestedNameSpecifier *DQual;
if (UsingDecl *UD = dyn_cast<UsingDecl>(D)) {
DTypename = UD->hasTypename();
DQual = UD->getQualifier();
} else if (UnresolvedUsingValueDecl *UD
= dyn_cast<UnresolvedUsingValueDecl>(D)) {
DTypename = false;
DQual = UD->getQualifier();
} else if (UnresolvedUsingTypenameDecl *UD
= dyn_cast<UnresolvedUsingTypenameDecl>(D)) {
DTypename = true;
DQual = UD->getQualifier();
} else continue;
// using decls differ if one says 'typename' and the other doesn't.
// FIXME: non-dependent using decls?
if (HasTypenameKeyword != DTypename) continue;
// using decls differ if they name different scopes (but note that
// template instantiation can cause this check to trigger when it
// didn't before instantiation).
if (Context.getCanonicalNestedNameSpecifier(Qual) !=
Context.getCanonicalNestedNameSpecifier(DQual))
continue;
Diag(NameLoc, diag::err_using_decl_redeclaration) << SS.getRange();
Diag(D->getLocation(), diag::note_using_decl) << 1;
return true;
}
return false;
}
/// Checks that the given nested-name qualifier used in a using decl
/// in the current context is appropriately related to the current
/// scope. If an error is found, diagnoses it and returns true.
bool Sema::CheckUsingDeclQualifier(SourceLocation UsingLoc,
const CXXScopeSpec &SS,
const DeclarationNameInfo &NameInfo,
SourceLocation NameLoc) {
DeclContext *NamedContext = computeDeclContext(SS);
if (!CurContext->isRecord()) {
// C++03 [namespace.udecl]p3:
// C++0x [namespace.udecl]p8:
// A using-declaration for a class member shall be a member-declaration.
// If we weren't able to compute a valid scope, it must be a
// dependent class scope.
if (!NamedContext || NamedContext->isRecord()) {
auto *RD = dyn_cast<CXXRecordDecl>(NamedContext);
if (RD && RequireCompleteDeclContext(const_cast<CXXScopeSpec&>(SS), RD))
RD = nullptr;
Diag(NameLoc, diag::err_using_decl_can_not_refer_to_class_member)
<< SS.getRange();
// If we have a complete, non-dependent source type, try to suggest a
// way to get the same effect.
if (!RD)
return true;
// Find what this using-declaration was referring to.
LookupResult R(*this, NameInfo, LookupOrdinaryName);
R.setHideTags(false);
R.suppressDiagnostics();
LookupQualifiedName(R, RD);
if (R.getAsSingle<TypeDecl>()) {
if (getLangOpts().CPlusPlus11) {
// Convert 'using X::Y;' to 'using Y = X::Y;'.
Diag(SS.getBeginLoc(), diag::note_using_decl_class_member_workaround)
<< 0 // alias declaration
<< FixItHint::CreateInsertion(SS.getBeginLoc(),
NameInfo.getName().getAsString() +
" = ");
} else {
// Convert 'using X::Y;' to 'typedef X::Y Y;'.
SourceLocation InsertLoc =
PP.getLocForEndOfToken(NameInfo.getLocEnd());
Diag(InsertLoc, diag::note_using_decl_class_member_workaround)
<< 1 // typedef declaration
<< FixItHint::CreateReplacement(UsingLoc, "typedef")
<< FixItHint::CreateInsertion(
InsertLoc, " " + NameInfo.getName().getAsString());
}
} else if (R.getAsSingle<VarDecl>()) {
// Don't provide a fixit outside C++11 mode; we don't want to suggest
// repeating the type of the static data member here.
FixItHint FixIt;
if (getLangOpts().CPlusPlus11) {
// Convert 'using X::Y;' to 'auto &Y = X::Y;'.
FixIt = FixItHint::CreateReplacement(
UsingLoc, "auto &" + NameInfo.getName().getAsString() + " = ");
}
Diag(UsingLoc, diag::note_using_decl_class_member_workaround)
<< 2 // reference declaration
<< FixIt;
}
return true;
}
// Otherwise, everything is known to be fine.
return false;
}
// The current scope is a record.
// If the named context is dependent, we can't decide much.
if (!NamedContext) {
// FIXME: in C++0x, we can diagnose if we can prove that the
// nested-name-specifier does not refer to a base class, which is
// still possible in some cases.
// Otherwise we have to conservatively report that things might be
// okay.
return false;
}
if (!NamedContext->isRecord()) {
// Ideally this would point at the last name in the specifier,
// but we don't have that level of source info.
Diag(SS.getRange().getBegin(),
diag::err_using_decl_nested_name_specifier_is_not_class)
<< SS.getScopeRep() << SS.getRange();
return true;
}
if (!NamedContext->isDependentContext() &&
RequireCompleteDeclContext(const_cast<CXXScopeSpec&>(SS), NamedContext))
return true;
if (getLangOpts().CPlusPlus11) {
// C++0x [namespace.udecl]p3:
// In a using-declaration used as a member-declaration, the
// nested-name-specifier shall name a base class of the class
// being defined.
if (cast<CXXRecordDecl>(CurContext)->isProvablyNotDerivedFrom(
cast<CXXRecordDecl>(NamedContext))) {
if (CurContext == NamedContext) {
Diag(NameLoc,
diag::err_using_decl_nested_name_specifier_is_current_class)
<< SS.getRange();
return true;
}
Diag(SS.getRange().getBegin(),
diag::err_using_decl_nested_name_specifier_is_not_base_class)
<< SS.getScopeRep()
<< cast<CXXRecordDecl>(CurContext)
<< SS.getRange();
return true;
}
return false;
}
// C++03 [namespace.udecl]p4:
// A using-declaration used as a member-declaration shall refer
// to a member of a base class of the class being defined [etc.].
// Salient point: SS doesn't have to name a base class as long as
// lookup only finds members from base classes. Therefore we can
// diagnose here only if we can prove that that can't happen,
// i.e. if the class hierarchies provably don't intersect.
// TODO: it would be nice if "definitely valid" results were cached
// in the UsingDecl and UsingShadowDecl so that these checks didn't
// need to be repeated.
struct UserData {
llvm::SmallPtrSet<const CXXRecordDecl*, 4> Bases;
static bool collect(const CXXRecordDecl *Base, void *OpaqueData) {
UserData *Data = reinterpret_cast<UserData*>(OpaqueData);
Data->Bases.insert(Base);
return true;
}
bool hasDependentBases(const CXXRecordDecl *Class) {
return !Class->forallBases(collect, this);
}
/// Returns true if the base is dependent or is one of the
/// accumulated base classes.
static bool doesNotContain(const CXXRecordDecl *Base, void *OpaqueData) {
UserData *Data = reinterpret_cast<UserData*>(OpaqueData);
return !Data->Bases.count(Base);
}
bool mightShareBases(const CXXRecordDecl *Class) {
return Bases.count(Class) || !Class->forallBases(doesNotContain, this);
}
};
UserData Data;
// Returns false if we find a dependent base.
if (Data.hasDependentBases(cast<CXXRecordDecl>(CurContext)))
return false;
// Returns false if the class has a dependent base or if it or one
// of its bases is present in the base set of the current context.
if (Data.mightShareBases(cast<CXXRecordDecl>(NamedContext)))
return false;
Diag(SS.getRange().getBegin(),
diag::err_using_decl_nested_name_specifier_is_not_base_class)
<< SS.getScopeRep()
<< cast<CXXRecordDecl>(CurContext)
<< SS.getRange();
return true;
}
Decl *Sema::ActOnAliasDeclaration(Scope *S,
AccessSpecifier AS,
MultiTemplateParamsArg TemplateParamLists,
SourceLocation UsingLoc,
UnqualifiedId &Name,
AttributeList *AttrList,
TypeResult Type) {
// Skip up to the relevant declaration scope.
while (S->getFlags() & Scope::TemplateParamScope)
S = S->getParent();
assert((S->getFlags() & Scope::DeclScope) &&
"got alias-declaration outside of declaration scope");
if (Type.isInvalid())
return nullptr;
bool Invalid = false;
DeclarationNameInfo NameInfo = GetNameFromUnqualifiedId(Name);
TypeSourceInfo *TInfo = nullptr;
GetTypeFromParser(Type.get(), &TInfo);
if (DiagnoseClassNameShadow(CurContext, NameInfo))
return nullptr;
if (DiagnoseUnexpandedParameterPack(Name.StartLocation, TInfo,
UPPC_DeclarationType)) {
Invalid = true;
TInfo = Context.getTrivialTypeSourceInfo(Context.IntTy,
TInfo->getTypeLoc().getBeginLoc());
}
LookupResult Previous(*this, NameInfo, LookupOrdinaryName, ForRedeclaration);
LookupName(Previous, S);
// Warn about shadowing the name of a template parameter.
if (Previous.isSingleResult() &&
Previous.getFoundDecl()->isTemplateParameter()) {
DiagnoseTemplateParameterShadow(Name.StartLocation,Previous.getFoundDecl());
Previous.clear();
}
assert(Name.Kind == UnqualifiedId::IK_Identifier &&
"name in alias declaration must be an identifier");
TypeAliasDecl *NewTD = TypeAliasDecl::Create(Context, CurContext, UsingLoc,
Name.StartLocation,
Name.Identifier, TInfo);
NewTD->setAccess(AS);
if (Invalid)
NewTD->setInvalidDecl();
ProcessDeclAttributeList(S, NewTD, AttrList);
CheckTypedefForVariablyModifiedType(S, NewTD);
Invalid |= NewTD->isInvalidDecl();
bool Redeclaration = false;
NamedDecl *NewND;
if (TemplateParamLists.size()) {
TypeAliasTemplateDecl *OldDecl = nullptr;
TemplateParameterList *OldTemplateParams = nullptr;
if (TemplateParamLists.size() != 1) {
Diag(UsingLoc, diag::err_alias_template_extra_headers)
<< SourceRange(TemplateParamLists[1]->getTemplateLoc(),
TemplateParamLists[TemplateParamLists.size()-1]->getRAngleLoc());
}
TemplateParameterList *TemplateParams = TemplateParamLists[0];
// Only consider previous declarations in the same scope.
FilterLookupForScope(Previous, CurContext, S, /*ConsiderLinkage*/false,
/*ExplicitInstantiationOrSpecialization*/false);
if (!Previous.empty()) {
Redeclaration = true;
OldDecl = Previous.getAsSingle<TypeAliasTemplateDecl>();
if (!OldDecl && !Invalid) {
Diag(UsingLoc, diag::err_redefinition_different_kind)
<< Name.Identifier;
NamedDecl *OldD = Previous.getRepresentativeDecl();
if (OldD->getLocation().isValid())
Diag(OldD->getLocation(), diag::note_previous_definition);
Invalid = true;
}
if (!Invalid && OldDecl && !OldDecl->isInvalidDecl()) {
if (TemplateParameterListsAreEqual(TemplateParams,
OldDecl->getTemplateParameters(),
/*Complain=*/true,
TPL_TemplateMatch))
OldTemplateParams = OldDecl->getTemplateParameters();
else
Invalid = true;
TypeAliasDecl *OldTD = OldDecl->getTemplatedDecl();
if (!Invalid &&
!Context.hasSameType(OldTD->getUnderlyingType(),
NewTD->getUnderlyingType())) {
// FIXME: The C++0x standard does not clearly say this is ill-formed,
// but we can't reasonably accept it.
Diag(NewTD->getLocation(), diag::err_redefinition_different_typedef)
<< 2 << NewTD->getUnderlyingType() << OldTD->getUnderlyingType();
if (OldTD->getLocation().isValid())
Diag(OldTD->getLocation(), diag::note_previous_definition);
Invalid = true;
}
}
}
// Merge any previous default template arguments into our parameters,
// and check the parameter list.
if (CheckTemplateParameterList(TemplateParams, OldTemplateParams,
TPC_TypeAliasTemplate))
return nullptr;
TypeAliasTemplateDecl *NewDecl =
TypeAliasTemplateDecl::Create(Context, CurContext, UsingLoc,
Name.Identifier, TemplateParams,
NewTD);
NewDecl->setAccess(AS);
if (Invalid)
NewDecl->setInvalidDecl();
else if (OldDecl)
NewDecl->setPreviousDecl(OldDecl);
NewND = NewDecl;
} else {
ActOnTypedefNameDecl(S, CurContext, NewTD, Previous, Redeclaration);
NewND = NewTD;
}
if (!Redeclaration)
PushOnScopeChains(NewND, S);
ActOnDocumentableDecl(NewND);
return NewND;
}
Decl *Sema::ActOnNamespaceAliasDef(Scope *S,
SourceLocation NamespaceLoc,
SourceLocation AliasLoc,
IdentifierInfo *Alias,
CXXScopeSpec &SS,
SourceLocation IdentLoc,
IdentifierInfo *Ident) {
// Lookup the namespace name.
LookupResult R(*this, Ident, IdentLoc, LookupNamespaceName);
LookupParsedName(R, S, &SS);
// Check if we have a previous declaration with the same name.
NamedDecl *PrevDecl
= LookupSingleName(S, Alias, AliasLoc, LookupOrdinaryName,
ForRedeclaration);
if (PrevDecl && !isDeclInScope(PrevDecl, CurContext, S))
PrevDecl = nullptr;
if (PrevDecl) {
if (NamespaceAliasDecl *AD = dyn_cast<NamespaceAliasDecl>(PrevDecl)) {
// We already have an alias with the same name that points to the same
// namespace, so don't create a new one.
// FIXME: At some point, we'll want to create the (redundant)
// declaration to maintain better source information.
if (!R.isAmbiguous() && !R.empty() &&
AD->getNamespace()->Equals(getNamespaceDecl(R.getFoundDecl())))
return nullptr;
}
unsigned DiagID = isa<NamespaceDecl>(PrevDecl) ? diag::err_redefinition :
diag::err_redefinition_different_kind;
Diag(AliasLoc, DiagID) << Alias;
Diag(PrevDecl->getLocation(), diag::note_previous_definition);
return nullptr;
}
if (R.isAmbiguous())
return nullptr;
if (R.empty()) {
if (!TryNamespaceTypoCorrection(*this, R, S, SS, IdentLoc, Ident)) {
Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange();
return nullptr;
}
}
NamespaceAliasDecl *AliasDecl =
NamespaceAliasDecl::Create(Context, CurContext, NamespaceLoc, AliasLoc,
Alias, SS.getWithLocInContext(Context),
IdentLoc, R.getFoundDecl());
PushOnScopeChains(AliasDecl, S);
return AliasDecl;
}
Sema::ImplicitExceptionSpecification
Sema::ComputeDefaultedDefaultCtorExceptionSpec(SourceLocation Loc,
CXXMethodDecl *MD) {
CXXRecordDecl *ClassDecl = MD->getParent();
// C++ [except.spec]p14:
// An implicitly declared special member function (Clause 12) shall have an
// exception-specification. [...]
ImplicitExceptionSpecification ExceptSpec(*this);
if (ClassDecl->isInvalidDecl())
return ExceptSpec;
// Direct base-class constructors.
for (const auto &B : ClassDecl->bases()) {
if (B.isVirtual()) // Handled below.
continue;
if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
CXXConstructorDecl *Constructor = LookupDefaultConstructor(BaseClassDecl);
// If this is a deleted function, add it anyway. This might be conformant
// with the standard. This might not. I'm not sure. It might not matter.
if (Constructor)
ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
}
}
// Virtual base-class constructors.
for (const auto &B : ClassDecl->vbases()) {
if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
CXXConstructorDecl *Constructor = LookupDefaultConstructor(BaseClassDecl);
// If this is a deleted function, add it anyway. This might be conformant
// with the standard. This might not. I'm not sure. It might not matter.
if (Constructor)
ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
}
}
// Field constructors.
for (const auto *F : ClassDecl->fields()) {
if (F->hasInClassInitializer()) {
if (Expr *E = F->getInClassInitializer())
ExceptSpec.CalledExpr(E);
else if (!F->isInvalidDecl())
// DR1351:
// If the brace-or-equal-initializer of a non-static data member
// invokes a defaulted default constructor of its class or of an
// enclosing class in a potentially evaluated subexpression, the
// program is ill-formed.
//
// This resolution is unworkable: the exception specification of the
// default constructor can be needed in an unevaluated context, in
// particular, in the operand of a noexcept-expression, and we can be
// unable to compute an exception specification for an enclosed class.
//
// We do not allow an in-class initializer to require the evaluation
// of the exception specification for any in-class initializer whose
// definition is not lexically complete.
Diag(Loc, diag::err_in_class_initializer_references_def_ctor) << MD;
} else if (const RecordType *RecordTy
= Context.getBaseElementType(F->getType())->getAs<RecordType>()) {
CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
CXXConstructorDecl *Constructor = LookupDefaultConstructor(FieldRecDecl);
// If this is a deleted function, add it anyway. This might be conformant
// with the standard. This might not. I'm not sure. It might not matter.
// In particular, the problem is that this function never gets called. It
// might just be ill-formed because this function attempts to refer to
// a deleted function here.
if (Constructor)
ExceptSpec.CalledDecl(F->getLocation(), Constructor);
}
}
return ExceptSpec;
}
Sema::ImplicitExceptionSpecification
Sema::ComputeInheritingCtorExceptionSpec(CXXConstructorDecl *CD) {
CXXRecordDecl *ClassDecl = CD->getParent();
// C++ [except.spec]p14:
// An inheriting constructor [...] shall have an exception-specification. [...]
ImplicitExceptionSpecification ExceptSpec(*this);
if (ClassDecl->isInvalidDecl())
return ExceptSpec;
// Inherited constructor.
const CXXConstructorDecl *InheritedCD = CD->getInheritedConstructor();
const CXXRecordDecl *InheritedDecl = InheritedCD->getParent();
// FIXME: Copying or moving the parameters could add extra exceptions to the
// set, as could the default arguments for the inherited constructor. This
// will be addressed when we implement the resolution of core issue 1351.
ExceptSpec.CalledDecl(CD->getLocStart(), InheritedCD);
// Direct base-class constructors.
for (const auto &B : ClassDecl->bases()) {
if (B.isVirtual()) // Handled below.
continue;
if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
if (BaseClassDecl == InheritedDecl)
continue;
CXXConstructorDecl *Constructor = LookupDefaultConstructor(BaseClassDecl);
if (Constructor)
ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
}
}
// Virtual base-class constructors.
for (const auto &B : ClassDecl->vbases()) {
if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
if (BaseClassDecl == InheritedDecl)
continue;
CXXConstructorDecl *Constructor = LookupDefaultConstructor(BaseClassDecl);
if (Constructor)
ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
}
}
// Field constructors.
for (const auto *F : ClassDecl->fields()) {
if (F->hasInClassInitializer()) {
if (Expr *E = F->getInClassInitializer())
ExceptSpec.CalledExpr(E);
else if (!F->isInvalidDecl())
Diag(CD->getLocation(),
diag::err_in_class_initializer_references_def_ctor) << CD;
} else if (const RecordType *RecordTy
= Context.getBaseElementType(F->getType())->getAs<RecordType>()) {
CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
CXXConstructorDecl *Constructor = LookupDefaultConstructor(FieldRecDecl);
if (Constructor)
ExceptSpec.CalledDecl(F->getLocation(), Constructor);
}
}
return ExceptSpec;
}
namespace {
/// RAII object to register a special member as being currently declared.
struct DeclaringSpecialMember {
Sema &S;
Sema::SpecialMemberDecl D;
bool WasAlreadyBeingDeclared;
DeclaringSpecialMember(Sema &S, CXXRecordDecl *RD, Sema::CXXSpecialMember CSM)
: S(S), D(RD, CSM) {
WasAlreadyBeingDeclared = !S.SpecialMembersBeingDeclared.insert(D);
if (WasAlreadyBeingDeclared)
// This almost never happens, but if it does, ensure that our cache
// doesn't contain a stale result.
S.SpecialMemberCache.clear();
// FIXME: Register a note to be produced if we encounter an error while
// declaring the special member.
}
~DeclaringSpecialMember() {
if (!WasAlreadyBeingDeclared)
S.SpecialMembersBeingDeclared.erase(D);
}
/// \brief Are we already trying to declare this special member?
bool isAlreadyBeingDeclared() const {
return WasAlreadyBeingDeclared;
}
};
}
CXXConstructorDecl *Sema::DeclareImplicitDefaultConstructor(
CXXRecordDecl *ClassDecl) {
// C++ [class.ctor]p5:
// A default constructor for a class X is a constructor of class X
// that can be called without an argument. If there is no
// user-declared constructor for class X, a default constructor is
// implicitly declared. An implicitly-declared default constructor
// is an inline public member of its class.
assert(ClassDecl->needsImplicitDefaultConstructor() &&
"Should not build implicit default constructor!");
DeclaringSpecialMember DSM(*this, ClassDecl, CXXDefaultConstructor);
if (DSM.isAlreadyBeingDeclared())
return nullptr;
bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
CXXDefaultConstructor,
false);
// Create the actual constructor declaration.
CanQualType ClassType
= Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
SourceLocation ClassLoc = ClassDecl->getLocation();
DeclarationName Name
= Context.DeclarationNames.getCXXConstructorName(ClassType);
DeclarationNameInfo NameInfo(Name, ClassLoc);
CXXConstructorDecl *DefaultCon = CXXConstructorDecl::Create(
Context, ClassDecl, ClassLoc, NameInfo, /*Type*/QualType(),
/*TInfo=*/nullptr, /*isExplicit=*/false, /*isInline=*/true,
/*isImplicitlyDeclared=*/true, Constexpr);
DefaultCon->setAccess(AS_public);
DefaultCon->setDefaulted();
DefaultCon->setImplicit();
// Build an exception specification pointing back at this constructor.
FunctionProtoType::ExtProtoInfo EPI = getImplicitMethodEPI(*this, DefaultCon);
DefaultCon->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
// We don't need to use SpecialMemberIsTrivial here; triviality for default
// constructors is easy to compute.
DefaultCon->setTrivial(ClassDecl->hasTrivialDefaultConstructor());
if (ShouldDeleteSpecialMember(DefaultCon, CXXDefaultConstructor))
SetDeclDeleted(DefaultCon, ClassLoc);
// Note that we have declared this constructor.
++ASTContext::NumImplicitDefaultConstructorsDeclared;
if (Scope *S = getScopeForContext(ClassDecl))
PushOnScopeChains(DefaultCon, S, false);
ClassDecl->addDecl(DefaultCon);
return DefaultCon;
}
void Sema::DefineImplicitDefaultConstructor(SourceLocation CurrentLocation,
CXXConstructorDecl *Constructor) {
assert((Constructor->isDefaulted() && Constructor->isDefaultConstructor() &&
!Constructor->doesThisDeclarationHaveABody() &&
!Constructor->isDeleted()) &&
"DefineImplicitDefaultConstructor - call it for implicit default ctor");
CXXRecordDecl *ClassDecl = Constructor->getParent();
assert(ClassDecl && "DefineImplicitDefaultConstructor - invalid constructor");
SynthesizedFunctionScope Scope(*this, Constructor);
DiagnosticErrorTrap Trap(Diags);
if (SetCtorInitializers(Constructor, /*AnyErrors=*/false) ||
Trap.hasErrorOccurred()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXDefaultConstructor << Context.getTagDeclType(ClassDecl);
Constructor->setInvalidDecl();
return;
}
SourceLocation Loc = Constructor->getLocEnd().isValid()
? Constructor->getLocEnd()
: Constructor->getLocation();
Constructor->setBody(new (Context) CompoundStmt(Loc));
Constructor->markUsed(Context);
MarkVTableUsed(CurrentLocation, ClassDecl);
if (ASTMutationListener *L = getASTMutationListener()) {
L->CompletedImplicitDefinition(Constructor);
}
DiagnoseUninitializedFields(*this, Constructor);
}
void Sema::ActOnFinishDelayedMemberInitializers(Decl *D) {
// Perform any delayed checks on exception specifications.
CheckDelayedMemberExceptionSpecs();
}
namespace {
/// Information on inheriting constructors to declare.
class InheritingConstructorInfo {
public:
InheritingConstructorInfo(Sema &SemaRef, CXXRecordDecl *Derived)
: SemaRef(SemaRef), Derived(Derived) {
// Mark the constructors that we already have in the derived class.
//
// C++11 [class.inhctor]p3: [...] a constructor is implicitly declared [...]
// unless there is a user-declared constructor with the same signature in
// the class where the using-declaration appears.
visitAll(Derived, &InheritingConstructorInfo::noteDeclaredInDerived);
}
void inheritAll(CXXRecordDecl *RD) {
visitAll(RD, &InheritingConstructorInfo::inherit);
}
private:
/// Information about an inheriting constructor.
struct InheritingConstructor {
InheritingConstructor()
: DeclaredInDerived(false), BaseCtor(nullptr), DerivedCtor(nullptr) {}
/// If \c true, a constructor with this signature is already declared
/// in the derived class.
bool DeclaredInDerived;
/// The constructor which is inherited.
const CXXConstructorDecl *BaseCtor;
/// The derived constructor we declared.
CXXConstructorDecl *DerivedCtor;
};
/// Inheriting constructors with a given canonical type. There can be at
/// most one such non-template constructor, and any number of templated
/// constructors.
struct InheritingConstructorsForType {
InheritingConstructor NonTemplate;
SmallVector<std::pair<TemplateParameterList *, InheritingConstructor>, 4>
Templates;
InheritingConstructor &getEntry(Sema &S, const CXXConstructorDecl *Ctor) {
if (FunctionTemplateDecl *FTD = Ctor->getDescribedFunctionTemplate()) {
TemplateParameterList *ParamList = FTD->getTemplateParameters();
for (unsigned I = 0, N = Templates.size(); I != N; ++I)
if (S.TemplateParameterListsAreEqual(ParamList, Templates[I].first,
false, S.TPL_TemplateMatch))
return Templates[I].second;
Templates.push_back(std::make_pair(ParamList, InheritingConstructor()));
return Templates.back().second;
}
return NonTemplate;
}
};
/// Get or create the inheriting constructor record for a constructor.
InheritingConstructor &getEntry(const CXXConstructorDecl *Ctor,
QualType CtorType) {
return Map[CtorType.getCanonicalType()->castAs<FunctionProtoType>()]
.getEntry(SemaRef, Ctor);
}
typedef void (InheritingConstructorInfo::*VisitFn)(const CXXConstructorDecl*);
/// Process all constructors for a class.
void visitAll(const CXXRecordDecl *RD, VisitFn Callback) {
for (const auto *Ctor : RD->ctors())
(this->*Callback)(Ctor);
for (CXXRecordDecl::specific_decl_iterator<FunctionTemplateDecl>
I(RD->decls_begin()), E(RD->decls_end());
I != E; ++I) {
const FunctionDecl *FD = (*I)->getTemplatedDecl();
if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD))
(this->*Callback)(CD);
}
}
/// Note that a constructor (or constructor template) was declared in Derived.
void noteDeclaredInDerived(const CXXConstructorDecl *Ctor) {
getEntry(Ctor, Ctor->getType()).DeclaredInDerived = true;
}
/// Inherit a single constructor.
void inherit(const CXXConstructorDecl *Ctor) {
const FunctionProtoType *CtorType =
Ctor->getType()->castAs<FunctionProtoType>();
ArrayRef<QualType> ArgTypes(CtorType->getParamTypes());
FunctionProtoType::ExtProtoInfo EPI = CtorType->getExtProtoInfo();
SourceLocation UsingLoc = getUsingLoc(Ctor->getParent());
// Core issue (no number yet): the ellipsis is always discarded.
if (EPI.Variadic) {
SemaRef.Diag(UsingLoc, diag::warn_using_decl_constructor_ellipsis);
SemaRef.Diag(Ctor->getLocation(),
diag::note_using_decl_constructor_ellipsis);
EPI.Variadic = false;
}
// Declare a constructor for each number of parameters.
//
// C++11 [class.inhctor]p1:
// The candidate set of inherited constructors from the class X named in
// the using-declaration consists of [... modulo defects ...] for each
// constructor or constructor template of X, the set of constructors or
// constructor templates that results from omitting any ellipsis parameter
// specification and successively omitting parameters with a default
// argument from the end of the parameter-type-list
unsigned MinParams = minParamsToInherit(Ctor);
unsigned Params = Ctor->getNumParams();
if (Params >= MinParams) {
do
declareCtor(UsingLoc, Ctor,
SemaRef.Context.getFunctionType(
Ctor->getReturnType(), ArgTypes.slice(0, Params), EPI));
while (Params > MinParams &&
Ctor->getParamDecl(--Params)->hasDefaultArg());
}
}
/// Find the using-declaration which specified that we should inherit the
/// constructors of \p Base.
SourceLocation getUsingLoc(const CXXRecordDecl *Base) {
// No fancy lookup required; just look for the base constructor name
// directly within the derived class.
ASTContext &Context = SemaRef.Context;
DeclarationName Name = Context.DeclarationNames.getCXXConstructorName(
Context.getCanonicalType(Context.getRecordType(Base)));
DeclContext::lookup_const_result Decls = Derived->lookup(Name);
return Decls.empty() ? Derived->getLocation() : Decls[0]->getLocation();
}
unsigned minParamsToInherit(const CXXConstructorDecl *Ctor) {
// C++11 [class.inhctor]p3:
// [F]or each constructor template in the candidate set of inherited
// constructors, a constructor template is implicitly declared
if (Ctor->getDescribedFunctionTemplate())
return 0;
// For each non-template constructor in the candidate set of inherited
// constructors other than a constructor having no parameters or a
// copy/move constructor having a single parameter, a constructor is
// implicitly declared [...]
if (Ctor->getNumParams() == 0)
return 1;
if (Ctor->isCopyOrMoveConstructor())
return 2;
// Per discussion on core reflector, never inherit a constructor which
// would become a default, copy, or move constructor of Derived either.
const ParmVarDecl *PD = Ctor->getParamDecl(0);
const ReferenceType *RT = PD->getType()->getAs<ReferenceType>();
return (RT && RT->getPointeeCXXRecordDecl() == Derived) ? 2 : 1;
}
/// Declare a single inheriting constructor, inheriting the specified
/// constructor, with the given type.
void declareCtor(SourceLocation UsingLoc, const CXXConstructorDecl *BaseCtor,
QualType DerivedType) {
InheritingConstructor &Entry = getEntry(BaseCtor, DerivedType);
// C++11 [class.inhctor]p3:
// ... a constructor is implicitly declared with the same constructor
// characteristics unless there is a user-declared constructor with
// the same signature in the class where the using-declaration appears
if (Entry.DeclaredInDerived)
return;
// C++11 [class.inhctor]p7:
// If two using-declarations declare inheriting constructors with the
// same signature, the program is ill-formed
if (Entry.DerivedCtor) {
if (BaseCtor->getParent() != Entry.BaseCtor->getParent()) {
// Only diagnose this once per constructor.
if (Entry.DerivedCtor->isInvalidDecl())
return;
Entry.DerivedCtor->setInvalidDecl();
SemaRef.Diag(UsingLoc, diag::err_using_decl_constructor_conflict);
SemaRef.Diag(BaseCtor->getLocation(),
diag::note_using_decl_constructor_conflict_current_ctor);
SemaRef.Diag(Entry.BaseCtor->getLocation(),
diag::note_using_decl_constructor_conflict_previous_ctor);
SemaRef.Diag(Entry.DerivedCtor->getLocation(),
diag::note_using_decl_constructor_conflict_previous_using);
} else {
// Core issue (no number): if the same inheriting constructor is
// produced by multiple base class constructors from the same base
// class, the inheriting constructor is defined as deleted.
SemaRef.SetDeclDeleted(Entry.DerivedCtor, UsingLoc);
}
return;
}
ASTContext &Context = SemaRef.Context;
DeclarationName Name = Context.DeclarationNames.getCXXConstructorName(
Context.getCanonicalType(Context.getRecordType(Derived)));
DeclarationNameInfo NameInfo(Name, UsingLoc);
TemplateParameterList *TemplateParams = nullptr;
if (const FunctionTemplateDecl *FTD =
BaseCtor->getDescribedFunctionTemplate()) {
TemplateParams = FTD->getTemplateParameters();
// We're reusing template parameters from a different DeclContext. This
// is questionable at best, but works out because the template depth in
// both places is guaranteed to be 0.
// FIXME: Rebuild the template parameters in the new context, and
// transform the function type to refer to them.
}
// Build type source info pointing at the using-declaration. This is
// required by template instantiation.
TypeSourceInfo *TInfo =
Context.getTrivialTypeSourceInfo(DerivedType, UsingLoc);
FunctionProtoTypeLoc ProtoLoc =
TInfo->getTypeLoc().IgnoreParens().castAs<FunctionProtoTypeLoc>();
CXXConstructorDecl *DerivedCtor = CXXConstructorDecl::Create(
Context, Derived, UsingLoc, NameInfo, DerivedType,
TInfo, BaseCtor->isExplicit(), /*Inline=*/true,
/*ImplicitlyDeclared=*/true, /*Constexpr=*/BaseCtor->isConstexpr());
// Build an unevaluated exception specification for this constructor.
const FunctionProtoType *FPT = DerivedType->castAs<FunctionProtoType>();
FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
EPI.ExceptionSpecType = EST_Unevaluated;
EPI.ExceptionSpecDecl = DerivedCtor;
DerivedCtor->setType(Context.getFunctionType(FPT->getReturnType(),
FPT->getParamTypes(), EPI));
// Build the parameter declarations.
SmallVector<ParmVarDecl *, 16> ParamDecls;
for (unsigned I = 0, N = FPT->getNumParams(); I != N; ++I) {
TypeSourceInfo *TInfo =
Context.getTrivialTypeSourceInfo(FPT->getParamType(I), UsingLoc);
ParmVarDecl *PD = ParmVarDecl::Create(
Context, DerivedCtor, UsingLoc, UsingLoc, /*IdentifierInfo=*/nullptr,
FPT->getParamType(I), TInfo, SC_None, /*DefaultArg=*/nullptr);
PD->setScopeInfo(0, I);
PD->setImplicit();
ParamDecls.push_back(PD);
ProtoLoc.setParam(I, PD);
}
// Set up the new constructor.
DerivedCtor->setAccess(BaseCtor->getAccess());
DerivedCtor->setParams(ParamDecls);
DerivedCtor->setInheritedConstructor(BaseCtor);
if (BaseCtor->isDeleted())
SemaRef.SetDeclDeleted(DerivedCtor, UsingLoc);
// If this is a constructor template, build the template declaration.
if (TemplateParams) {
FunctionTemplateDecl *DerivedTemplate =
FunctionTemplateDecl::Create(SemaRef.Context, Derived, UsingLoc, Name,
TemplateParams, DerivedCtor);
DerivedTemplate->setAccess(BaseCtor->getAccess());
DerivedCtor->setDescribedFunctionTemplate(DerivedTemplate);
Derived->addDecl(DerivedTemplate);
} else {
Derived->addDecl(DerivedCtor);
}
Entry.BaseCtor = BaseCtor;
Entry.DerivedCtor = DerivedCtor;
}
Sema &SemaRef;
CXXRecordDecl *Derived;
typedef llvm::DenseMap<const Type *, InheritingConstructorsForType> MapType;
MapType Map;
};
}
void Sema::DeclareInheritingConstructors(CXXRecordDecl *ClassDecl) {
// Defer declaring the inheriting constructors until the class is
// instantiated.
if (ClassDecl->isDependentContext())
return;
// Find base classes from which we might inherit constructors.
SmallVector<CXXRecordDecl*, 4> InheritedBases;
for (const auto &BaseIt : ClassDecl->bases())
if (BaseIt.getInheritConstructors())
InheritedBases.push_back(BaseIt.getType()->getAsCXXRecordDecl());
// Go no further if we're not inheriting any constructors.
if (InheritedBases.empty())
return;
// Declare the inherited constructors.
InheritingConstructorInfo ICI(*this, ClassDecl);
for (unsigned I = 0, N = InheritedBases.size(); I != N; ++I)
ICI.inheritAll(InheritedBases[I]);
}
void Sema::DefineInheritingConstructor(SourceLocation CurrentLocation,
CXXConstructorDecl *Constructor) {
CXXRecordDecl *ClassDecl = Constructor->getParent();
assert(Constructor->getInheritedConstructor() &&
!Constructor->doesThisDeclarationHaveABody() &&
!Constructor->isDeleted());
SynthesizedFunctionScope Scope(*this, Constructor);
DiagnosticErrorTrap Trap(Diags);
if (SetCtorInitializers(Constructor, /*AnyErrors=*/false) ||
Trap.hasErrorOccurred()) {
Diag(CurrentLocation, diag::note_inhctor_synthesized_at)
<< Context.getTagDeclType(ClassDecl);
Constructor->setInvalidDecl();
return;
}
SourceLocation Loc = Constructor->getLocation();
Constructor->setBody(new (Context) CompoundStmt(Loc));
Constructor->markUsed(Context);
MarkVTableUsed(CurrentLocation, ClassDecl);
if (ASTMutationListener *L = getASTMutationListener()) {
L->CompletedImplicitDefinition(Constructor);
}
}
Sema::ImplicitExceptionSpecification
Sema::ComputeDefaultedDtorExceptionSpec(CXXMethodDecl *MD) {
CXXRecordDecl *ClassDecl = MD->getParent();
// C++ [except.spec]p14:
// An implicitly declared special member function (Clause 12) shall have
// an exception-specification.
ImplicitExceptionSpecification ExceptSpec(*this);
if (ClassDecl->isInvalidDecl())
return ExceptSpec;
// Direct base-class destructors.
for (const auto &B : ClassDecl->bases()) {
if (B.isVirtual()) // Handled below.
continue;
if (const RecordType *BaseType = B.getType()->getAs<RecordType>())
ExceptSpec.CalledDecl(B.getLocStart(),
LookupDestructor(cast<CXXRecordDecl>(BaseType->getDecl())));
}
// Virtual base-class destructors.
for (const auto &B : ClassDecl->vbases()) {
if (const RecordType *BaseType = B.getType()->getAs<RecordType>())
ExceptSpec.CalledDecl(B.getLocStart(),
LookupDestructor(cast<CXXRecordDecl>(BaseType->getDecl())));
}
// Field destructors.
for (const auto *F : ClassDecl->fields()) {
if (const RecordType *RecordTy
= Context.getBaseElementType(F->getType())->getAs<RecordType>())
ExceptSpec.CalledDecl(F->getLocation(),
LookupDestructor(cast<CXXRecordDecl>(RecordTy->getDecl())));
}
return ExceptSpec;
}
CXXDestructorDecl *Sema::DeclareImplicitDestructor(CXXRecordDecl *ClassDecl) {
// C++ [class.dtor]p2:
// If a class has no user-declared destructor, a destructor is
// declared implicitly. An implicitly-declared destructor is an
// inline public member of its class.
assert(ClassDecl->needsImplicitDestructor());
DeclaringSpecialMember DSM(*this, ClassDecl, CXXDestructor);
if (DSM.isAlreadyBeingDeclared())
return nullptr;
// Create the actual destructor declaration.
CanQualType ClassType
= Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
SourceLocation ClassLoc = ClassDecl->getLocation();
DeclarationName Name
= Context.DeclarationNames.getCXXDestructorName(ClassType);
DeclarationNameInfo NameInfo(Name, ClassLoc);
CXXDestructorDecl *Destructor
= CXXDestructorDecl::Create(Context, ClassDecl, ClassLoc, NameInfo,
QualType(), nullptr, /*isInline=*/true,
/*isImplicitlyDeclared=*/true);
Destructor->setAccess(AS_public);
Destructor->setDefaulted();
Destructor->setImplicit();
// Build an exception specification pointing back at this destructor.
FunctionProtoType::ExtProtoInfo EPI = getImplicitMethodEPI(*this, Destructor);
Destructor->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
AddOverriddenMethods(ClassDecl, Destructor);
// We don't need to use SpecialMemberIsTrivial here; triviality for
// destructors is easy to compute.
Destructor->setTrivial(ClassDecl->hasTrivialDestructor());
if (ShouldDeleteSpecialMember(Destructor, CXXDestructor))
SetDeclDeleted(Destructor, ClassLoc);
// Note that we have declared this destructor.
++ASTContext::NumImplicitDestructorsDeclared;
// Introduce this destructor into its scope.
if (Scope *S = getScopeForContext(ClassDecl))
PushOnScopeChains(Destructor, S, false);
ClassDecl->addDecl(Destructor);
return Destructor;
}
void Sema::DefineImplicitDestructor(SourceLocation CurrentLocation,
CXXDestructorDecl *Destructor) {
assert((Destructor->isDefaulted() &&
!Destructor->doesThisDeclarationHaveABody() &&
!Destructor->isDeleted()) &&
"DefineImplicitDestructor - call it for implicit default dtor");
CXXRecordDecl *ClassDecl = Destructor->getParent();
assert(ClassDecl && "DefineImplicitDestructor - invalid destructor");
if (Destructor->isInvalidDecl())
return;
SynthesizedFunctionScope Scope(*this, Destructor);
DiagnosticErrorTrap Trap(Diags);
MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
Destructor->getParent());
if (CheckDestructor(Destructor) || Trap.hasErrorOccurred()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXDestructor << Context.getTagDeclType(ClassDecl);
Destructor->setInvalidDecl();
return;
}
SourceLocation Loc = Destructor->getLocEnd().isValid()
? Destructor->getLocEnd()
: Destructor->getLocation();
Destructor->setBody(new (Context) CompoundStmt(Loc));
Destructor->markUsed(Context);
MarkVTableUsed(CurrentLocation, ClassDecl);
if (ASTMutationListener *L = getASTMutationListener()) {
L->CompletedImplicitDefinition(Destructor);
}
}
/// \brief Perform any semantic analysis which needs to be delayed until all
/// pending class member declarations have been parsed.
void Sema::ActOnFinishCXXMemberDecls() {
// If the context is an invalid C++ class, just suppress these checks.
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(CurContext)) {
if (Record->isInvalidDecl()) {
DelayedDefaultedMemberExceptionSpecs.clear();
DelayedDestructorExceptionSpecChecks.clear();
return;
}
}
}
void Sema::AdjustDestructorExceptionSpec(CXXRecordDecl *ClassDecl,
CXXDestructorDecl *Destructor) {
assert(getLangOpts().CPlusPlus11 &&
"adjusting dtor exception specs was introduced in c++11");
// C++11 [class.dtor]p3:
// A declaration of a destructor that does not have an exception-
// specification is implicitly considered to have the same exception-
// specification as an implicit declaration.
const FunctionProtoType *DtorType = Destructor->getType()->
getAs<FunctionProtoType>();
if (DtorType->hasExceptionSpec())
return;
// Replace the destructor's type, building off the existing one. Fortunately,
// the only thing of interest in the destructor type is its extended info.
// The return and arguments are fixed.
FunctionProtoType::ExtProtoInfo EPI = DtorType->getExtProtoInfo();
EPI.ExceptionSpecType = EST_Unevaluated;
EPI.ExceptionSpecDecl = Destructor;
Destructor->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
// FIXME: If the destructor has a body that could throw, and the newly created
// spec doesn't allow exceptions, we should emit a warning, because this
// change in behavior can break conforming C++03 programs at runtime.
// However, we don't have a body or an exception specification yet, so it
// needs to be done somewhere else.
}
namespace {
/// \brief An abstract base class for all helper classes used in building the
// copy/move operators. These classes serve as factory functions and help us
// avoid using the same Expr* in the AST twice.
class ExprBuilder {
ExprBuilder(const ExprBuilder&) LLVM_DELETED_FUNCTION;
ExprBuilder &operator=(const ExprBuilder&) LLVM_DELETED_FUNCTION;
protected:
static Expr *assertNotNull(Expr *E) {
assert(E && "Expression construction must not fail.");
return E;
}
public:
ExprBuilder() {}
virtual ~ExprBuilder() {}
virtual Expr *build(Sema &S, SourceLocation Loc) const = 0;
};
class RefBuilder: public ExprBuilder {
VarDecl *Var;
QualType VarType;
public:
virtual Expr *build(Sema &S, SourceLocation Loc) const override {
return assertNotNull(S.BuildDeclRefExpr(Var, VarType, VK_LValue, Loc).get());
}
RefBuilder(VarDecl *Var, QualType VarType)
: Var(Var), VarType(VarType) {}
};
class ThisBuilder: public ExprBuilder {
public:
virtual Expr *build(Sema &S, SourceLocation Loc) const override {
return assertNotNull(S.ActOnCXXThis(Loc).getAs<Expr>());
}
};
class CastBuilder: public ExprBuilder {
const ExprBuilder &Builder;
QualType Type;
ExprValueKind Kind;
const CXXCastPath &Path;
public:
virtual Expr *build(Sema &S, SourceLocation Loc) const override {
return assertNotNull(S.ImpCastExprToType(Builder.build(S, Loc), Type,
CK_UncheckedDerivedToBase, Kind,
&Path).get());
}
CastBuilder(const ExprBuilder &Builder, QualType Type, ExprValueKind Kind,
const CXXCastPath &Path)
: Builder(Builder), Type(Type), Kind(Kind), Path(Path) {}
};
class DerefBuilder: public ExprBuilder {
const ExprBuilder &Builder;
public:
virtual Expr *build(Sema &S, SourceLocation Loc) const override {
return assertNotNull(
S.CreateBuiltinUnaryOp(Loc, UO_Deref, Builder.build(S, Loc)).get());
}
DerefBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
};
class MemberBuilder: public ExprBuilder {
const ExprBuilder &Builder;
QualType Type;
CXXScopeSpec SS;
bool IsArrow;
LookupResult &MemberLookup;
public:
virtual Expr *build(Sema &S, SourceLocation Loc) const override {
return assertNotNull(S.BuildMemberReferenceExpr(
Builder.build(S, Loc), Type, Loc, IsArrow, SS, SourceLocation(),
nullptr, MemberLookup, nullptr).get());
}
MemberBuilder(const ExprBuilder &Builder, QualType Type, bool IsArrow,
LookupResult &MemberLookup)
: Builder(Builder), Type(Type), IsArrow(IsArrow),
MemberLookup(MemberLookup) {}
};
class MoveCastBuilder: public ExprBuilder {
const ExprBuilder &Builder;
public:
virtual Expr *build(Sema &S, SourceLocation Loc) const override {
return assertNotNull(CastForMoving(S, Builder.build(S, Loc)));
}
MoveCastBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
};
class LvalueConvBuilder: public ExprBuilder {
const ExprBuilder &Builder;
public:
virtual Expr *build(Sema &S, SourceLocation Loc) const override {
return assertNotNull(
S.DefaultLvalueConversion(Builder.build(S, Loc)).get());
}
LvalueConvBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
};
class SubscriptBuilder: public ExprBuilder {
const ExprBuilder &Base;
const ExprBuilder &Index;
public:
virtual Expr *build(Sema &S, SourceLocation Loc) const override {
return assertNotNull(S.CreateBuiltinArraySubscriptExpr(
Base.build(S, Loc), Loc, Index.build(S, Loc), Loc).get());
}
SubscriptBuilder(const ExprBuilder &Base, const ExprBuilder &Index)
: Base(Base), Index(Index) {}
};
} // end anonymous namespace
/// When generating a defaulted copy or move assignment operator, if a field
/// should be copied with __builtin_memcpy rather than via explicit assignments,
/// do so. This optimization only applies for arrays of scalars, and for arrays
/// of class type where the selected copy/move-assignment operator is trivial.
static StmtResult
buildMemcpyForAssignmentOp(Sema &S, SourceLocation Loc, QualType T,
const ExprBuilder &ToB, const ExprBuilder &FromB) {
// Compute the size of the memory buffer to be copied.
QualType SizeType = S.Context.getSizeType();
llvm::APInt Size(S.Context.getTypeSize(SizeType),
S.Context.getTypeSizeInChars(T).getQuantity());
// Take the address of the field references for "from" and "to". We
// directly construct UnaryOperators here because semantic analysis
// does not permit us to take the address of an xvalue.
Expr *From = FromB.build(S, Loc);
From = new (S.Context) UnaryOperator(From, UO_AddrOf,
S.Context.getPointerType(From->getType()),
VK_RValue, OK_Ordinary, Loc);
Expr *To = ToB.build(S, Loc);
To = new (S.Context) UnaryOperator(To, UO_AddrOf,
S.Context.getPointerType(To->getType()),
VK_RValue, OK_Ordinary, Loc);
const Type *E = T->getBaseElementTypeUnsafe();
bool NeedsCollectableMemCpy =
E->isRecordType() && E->getAs<RecordType>()->getDecl()->hasObjectMember();
// Create a reference to the __builtin_objc_memmove_collectable function
StringRef MemCpyName = NeedsCollectableMemCpy ?
"__builtin_objc_memmove_collectable" :
"__builtin_memcpy";
LookupResult R(S, &S.Context.Idents.get(MemCpyName), Loc,
Sema::LookupOrdinaryName);
S.LookupName(R, S.TUScope, true);
FunctionDecl *MemCpy = R.getAsSingle<FunctionDecl>();
if (!MemCpy)
// Something went horribly wrong earlier, and we will have complained
// about it.
return StmtError();
ExprResult MemCpyRef = S.BuildDeclRefExpr(MemCpy, S.Context.BuiltinFnTy,
VK_RValue, Loc, nullptr);
assert(MemCpyRef.isUsable() && "Builtin reference cannot fail");
Expr *CallArgs[] = {
To, From, IntegerLiteral::Create(S.Context, Size, SizeType, Loc)
};
ExprResult Call = S.ActOnCallExpr(/*Scope=*/nullptr, MemCpyRef.get(),
Loc, CallArgs, Loc);
assert(!Call.isInvalid() && "Call to __builtin_memcpy cannot fail!");
return Call.getAs<Stmt>();
}
/// \brief Builds a statement that copies/moves the given entity from \p From to
/// \c To.
///
/// This routine is used to copy/move the members of a class with an
/// implicitly-declared copy/move assignment operator. When the entities being
/// copied are arrays, this routine builds for loops to copy them.
///
/// \param S The Sema object used for type-checking.
///
/// \param Loc The location where the implicit copy/move is being generated.
///
/// \param T The type of the expressions being copied/moved. Both expressions
/// must have this type.
///
/// \param To The expression we are copying/moving to.
///
/// \param From The expression we are copying/moving from.
///
/// \param CopyingBaseSubobject Whether we're copying/moving a base subobject.
/// Otherwise, it's a non-static member subobject.
///
/// \param Copying Whether we're copying or moving.
///
/// \param Depth Internal parameter recording the depth of the recursion.
///
/// \returns A statement or a loop that copies the expressions, or StmtResult(0)
/// if a memcpy should be used instead.
static StmtResult
buildSingleCopyAssignRecursively(Sema &S, SourceLocation Loc, QualType T,
const ExprBuilder &To, const ExprBuilder &From,
bool CopyingBaseSubobject, bool Copying,
unsigned Depth = 0) {
// C++11 [class.copy]p28:
// Each subobject is assigned in the manner appropriate to its type:
//
// - if the subobject is of class type, as if by a call to operator= with
// the subobject as the object expression and the corresponding
// subobject of x as a single function argument (as if by explicit
// qualification; that is, ignoring any possible virtual overriding
// functions in more derived classes);
//
// C++03 [class.copy]p13:
// - if the subobject is of class type, the copy assignment operator for
// the class is used (as if by explicit qualification; that is,
// ignoring any possible virtual overriding functions in more derived
// classes);
if (const RecordType *RecordTy = T->getAs<RecordType>()) {
CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
// Look for operator=.
DeclarationName Name
= S.Context.DeclarationNames.getCXXOperatorName(OO_Equal);
LookupResult OpLookup(S, Name, Loc, Sema::LookupOrdinaryName);
S.LookupQualifiedName(OpLookup, ClassDecl, false);
// Prior to C++11, filter out any result that isn't a copy/move-assignment
// operator.
if (!S.getLangOpts().CPlusPlus11) {
LookupResult::Filter F = OpLookup.makeFilter();
while (F.hasNext()) {
NamedDecl *D = F.next();
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
if (Method->isCopyAssignmentOperator() ||
(!Copying && Method->isMoveAssignmentOperator()))
continue;
F.erase();
}
F.done();
}
// Suppress the protected check (C++ [class.protected]) for each of the
// assignment operators we found. This strange dance is required when
// we're assigning via a base classes's copy-assignment operator. To
// ensure that we're getting the right base class subobject (without
// ambiguities), we need to cast "this" to that subobject type; to
// ensure that we don't go through the virtual call mechanism, we need
// to qualify the operator= name with the base class (see below). However,
// this means that if the base class has a protected copy assignment
// operator, the protected member access check will fail. So, we
// rewrite "protected" access to "public" access in this case, since we
// know by construction that we're calling from a derived class.
if (CopyingBaseSubobject) {
for (LookupResult::iterator L = OpLookup.begin(), LEnd = OpLookup.end();
L != LEnd; ++L) {
if (L.getAccess() == AS_protected)
L.setAccess(AS_public);
}
}
// Create the nested-name-specifier that will be used to qualify the
// reference to operator=; this is required to suppress the virtual
// call mechanism.
CXXScopeSpec SS;
const Type *CanonicalT = S.Context.getCanonicalType(T.getTypePtr());
SS.MakeTrivial(S.Context,
NestedNameSpecifier::Create(S.Context, nullptr, false,
CanonicalT),
Loc);
// Create the reference to operator=.
ExprResult OpEqualRef
= S.BuildMemberReferenceExpr(To.build(S, Loc), T, Loc, /*isArrow=*/false,
SS, /*TemplateKWLoc=*/SourceLocation(),
/*FirstQualifierInScope=*/nullptr,
OpLookup,
/*TemplateArgs=*/nullptr,
/*SuppressQualifierCheck=*/true);
if (OpEqualRef.isInvalid())
return StmtError();
// Build the call to the assignment operator.
Expr *FromInst = From.build(S, Loc);
ExprResult Call = S.BuildCallToMemberFunction(/*Scope=*/nullptr,
OpEqualRef.getAs<Expr>(),
Loc, FromInst, Loc);
if (Call.isInvalid())
return StmtError();
// If we built a call to a trivial 'operator=' while copying an array,
// bail out. We'll replace the whole shebang with a memcpy.
CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(Call.get());
if (CE && CE->getMethodDecl()->isTrivial() && Depth)
return StmtResult((Stmt*)nullptr);
// Convert to an expression-statement, and clean up any produced
// temporaries.
return S.ActOnExprStmt(Call);
}
// - if the subobject is of scalar type, the built-in assignment
// operator is used.
const ConstantArrayType *ArrayTy = S.Context.getAsConstantArrayType(T);
if (!ArrayTy) {
ExprResult Assignment = S.CreateBuiltinBinOp(
Loc, BO_Assign, To.build(S, Loc), From.build(S, Loc));
if (Assignment.isInvalid())
return StmtError();
return S.ActOnExprStmt(Assignment);
}
// - if the subobject is an array, each element is assigned, in the
// manner appropriate to the element type;
// Construct a loop over the array bounds, e.g.,
//
// for (__SIZE_TYPE__ i0 = 0; i0 != array-size; ++i0)
//
// that will copy each of the array elements.
QualType SizeType = S.Context.getSizeType();
// Create the iteration variable.
IdentifierInfo *IterationVarName = nullptr;
{
SmallString<8> Str;
llvm::raw_svector_ostream OS(Str);
OS << "__i" << Depth;
IterationVarName = &S.Context.Idents.get(OS.str());
}
VarDecl *IterationVar = VarDecl::Create(S.Context, S.CurContext, Loc, Loc,
IterationVarName, SizeType,
S.Context.getTrivialTypeSourceInfo(SizeType, Loc),
SC_None);
// Initialize the iteration variable to zero.
llvm::APInt Zero(S.Context.getTypeSize(SizeType), 0);
IterationVar->setInit(IntegerLiteral::Create(S.Context, Zero, SizeType, Loc));
// Creates a reference to the iteration variable.
RefBuilder IterationVarRef(IterationVar, SizeType);
LvalueConvBuilder IterationVarRefRVal(IterationVarRef);
// Create the DeclStmt that holds the iteration variable.
Stmt *InitStmt = new (S.Context) DeclStmt(DeclGroupRef(IterationVar),Loc,Loc);
// Subscript the "from" and "to" expressions with the iteration variable.
SubscriptBuilder FromIndexCopy(From, IterationVarRefRVal);
MoveCastBuilder FromIndexMove(FromIndexCopy);
const ExprBuilder *FromIndex;
if (Copying)
FromIndex = &FromIndexCopy;
else
FromIndex = &FromIndexMove;
SubscriptBuilder ToIndex(To, IterationVarRefRVal);
// Build the copy/move for an individual element of the array.
StmtResult Copy =
buildSingleCopyAssignRecursively(S, Loc, ArrayTy->getElementType(),
ToIndex, *FromIndex, CopyingBaseSubobject,
Copying, Depth + 1);
// Bail out if copying fails or if we determined that we should use memcpy.
if (Copy.isInvalid() || !Copy.get())
return Copy;
// Create the comparison against the array bound.
llvm::APInt Upper
= ArrayTy->getSize().zextOrTrunc(S.Context.getTypeSize(SizeType));
Expr *Comparison
= new (S.Context) BinaryOperator(IterationVarRefRVal.build(S, Loc),
IntegerLiteral::Create(S.Context, Upper, SizeType, Loc),
BO_NE, S.Context.BoolTy,
VK_RValue, OK_Ordinary, Loc, false);
// Create the pre-increment of the iteration variable.
Expr *Increment
= new (S.Context) UnaryOperator(IterationVarRef.build(S, Loc), UO_PreInc,
SizeType, VK_LValue, OK_Ordinary, Loc);
// Construct the loop that copies all elements of this array.
return S.ActOnForStmt(Loc, Loc, InitStmt,
S.MakeFullExpr(Comparison),
nullptr, S.MakeFullDiscardedValueExpr(Increment),
Loc, Copy.get());
}
static StmtResult
buildSingleCopyAssign(Sema &S, SourceLocation Loc, QualType T,
const ExprBuilder &To, const ExprBuilder &From,
bool CopyingBaseSubobject, bool Copying) {
// Maybe we should use a memcpy?
if (T->isArrayType() && !T.isConstQualified() && !T.isVolatileQualified() &&
T.isTriviallyCopyableType(S.Context))
return buildMemcpyForAssignmentOp(S, Loc, T, To, From);
StmtResult Result(buildSingleCopyAssignRecursively(S, Loc, T, To, From,
CopyingBaseSubobject,
Copying, 0));
// If we ended up picking a trivial assignment operator for an array of a
// non-trivially-copyable class type, just emit a memcpy.
if (!Result.isInvalid() && !Result.get())
return buildMemcpyForAssignmentOp(S, Loc, T, To, From);
return Result;
}
Sema::ImplicitExceptionSpecification
Sema::ComputeDefaultedCopyAssignmentExceptionSpec(CXXMethodDecl *MD) {
CXXRecordDecl *ClassDecl = MD->getParent();
ImplicitExceptionSpecification ExceptSpec(*this);
if (ClassDecl->isInvalidDecl())
return ExceptSpec;
const FunctionProtoType *T = MD->getType()->castAs<FunctionProtoType>();
assert(T->getNumParams() == 1 && "not a copy assignment op");
unsigned ArgQuals =
T->getParamType(0).getNonReferenceType().getCVRQualifiers();
// C++ [except.spec]p14:
// An implicitly declared special member function (Clause 12) shall have an
// exception-specification. [...]
// It is unspecified whether or not an implicit copy assignment operator
// attempts to deduplicate calls to assignment operators of virtual bases are
// made. As such, this exception specification is effectively unspecified.
// Based on a similar decision made for constness in C++0x, we're erring on
// the side of assuming such calls to be made regardless of whether they
// actually happen.
for (const auto &Base : ClassDecl->bases()) {
if (Base.isVirtual())
continue;
CXXRecordDecl *BaseClassDecl
= cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
if (CXXMethodDecl *CopyAssign = LookupCopyingAssignment(BaseClassDecl,
ArgQuals, false, 0))
ExceptSpec.CalledDecl(Base.getLocStart(), CopyAssign);
}
for (const auto &Base : ClassDecl->vbases()) {
CXXRecordDecl *BaseClassDecl
= cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
if (CXXMethodDecl *CopyAssign = LookupCopyingAssignment(BaseClassDecl,
ArgQuals, false, 0))
ExceptSpec.CalledDecl(Base.getLocStart(), CopyAssign);
}
for (const auto *Field : ClassDecl->fields()) {
QualType FieldType = Context.getBaseElementType(Field->getType());
if (CXXRecordDecl *FieldClassDecl = FieldType->getAsCXXRecordDecl()) {
if (CXXMethodDecl *CopyAssign =
LookupCopyingAssignment(FieldClassDecl,
ArgQuals | FieldType.getCVRQualifiers(),
false, 0))
ExceptSpec.CalledDecl(Field->getLocation(), CopyAssign);
}
}
return ExceptSpec;
}
CXXMethodDecl *Sema::DeclareImplicitCopyAssignment(CXXRecordDecl *ClassDecl) {
// Note: The following rules are largely analoguous to the copy
// constructor rules. Note that virtual bases are not taken into account
// for determining the argument type of the operator. Note also that
// operators taking an object instead of a reference are allowed.
assert(ClassDecl->needsImplicitCopyAssignment());
DeclaringSpecialMember DSM(*this, ClassDecl, CXXCopyAssignment);
if (DSM.isAlreadyBeingDeclared())
return nullptr;
QualType ArgType = Context.getTypeDeclType(ClassDecl);
QualType RetType = Context.getLValueReferenceType(ArgType);
bool Const = ClassDecl->implicitCopyAssignmentHasConstParam();
if (Const)
ArgType = ArgType.withConst();
ArgType = Context.getLValueReferenceType(ArgType);
bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
CXXCopyAssignment,
Const);
// An implicitly-declared copy assignment operator is an inline public
// member of its class.
DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
SourceLocation ClassLoc = ClassDecl->getLocation();
DeclarationNameInfo NameInfo(Name, ClassLoc);
CXXMethodDecl *CopyAssignment =
CXXMethodDecl::Create(Context, ClassDecl, ClassLoc, NameInfo, QualType(),
/*TInfo=*/nullptr, /*StorageClass=*/SC_None,
/*isInline=*/true, Constexpr, SourceLocation());
CopyAssignment->setAccess(AS_public);
CopyAssignment->setDefaulted();
CopyAssignment->setImplicit();
// Build an exception specification pointing back at this member.
FunctionProtoType::ExtProtoInfo EPI =
getImplicitMethodEPI(*this, CopyAssignment);
CopyAssignment->setType(Context.getFunctionType(RetType, ArgType, EPI));
// Add the parameter to the operator.
ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyAssignment,
ClassLoc, ClassLoc,
/*Id=*/nullptr, ArgType,
/*TInfo=*/nullptr, SC_None,
nullptr);
CopyAssignment->setParams(FromParam);
AddOverriddenMethods(ClassDecl, CopyAssignment);
CopyAssignment->setTrivial(
ClassDecl->needsOverloadResolutionForCopyAssignment()
? SpecialMemberIsTrivial(CopyAssignment, CXXCopyAssignment)
: ClassDecl->hasTrivialCopyAssignment());
if (ShouldDeleteSpecialMember(CopyAssignment, CXXCopyAssignment))
SetDeclDeleted(CopyAssignment, ClassLoc);
// Note that we have added this copy-assignment operator.
++ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
if (Scope *S = getScopeForContext(ClassDecl))
PushOnScopeChains(CopyAssignment, S, false);
ClassDecl->addDecl(CopyAssignment);
return CopyAssignment;
}
/// Diagnose an implicit copy operation for a class which is odr-used, but
/// which is deprecated because the class has a user-declared copy constructor,
/// copy assignment operator, or destructor.
static void diagnoseDeprecatedCopyOperation(Sema &S, CXXMethodDecl *CopyOp,
SourceLocation UseLoc) {
assert(CopyOp->isImplicit());
CXXRecordDecl *RD = CopyOp->getParent();
CXXMethodDecl *UserDeclaredOperation = nullptr;
// In Microsoft mode, assignment operations don't affect constructors and
// vice versa.
if (RD->hasUserDeclaredDestructor()) {
UserDeclaredOperation = RD->getDestructor();
} else if (!isa<CXXConstructorDecl>(CopyOp) &&
RD->hasUserDeclaredCopyConstructor() &&
!S.getLangOpts().MSVCCompat) {
// Find any user-declared copy constructor.
for (auto *I : RD->ctors()) {
if (I->isCopyConstructor()) {
UserDeclaredOperation = I;
break;
}
}
assert(UserDeclaredOperation);
} else if (isa<CXXConstructorDecl>(CopyOp) &&
RD->hasUserDeclaredCopyAssignment() &&
!S.getLangOpts().MSVCCompat) {
// Find any user-declared move assignment operator.
for (auto *I : RD->methods()) {
if (I->isCopyAssignmentOperator()) {
UserDeclaredOperation = I;
break;
}
}
assert(UserDeclaredOperation);
}
if (UserDeclaredOperation) {
S.Diag(UserDeclaredOperation->getLocation(),
diag::warn_deprecated_copy_operation)
<< RD << /*copy assignment*/!isa<CXXConstructorDecl>(CopyOp)
<< /*destructor*/isa<CXXDestructorDecl>(UserDeclaredOperation);
S.Diag(UseLoc, diag::note_member_synthesized_at)
<< (isa<CXXConstructorDecl>(CopyOp) ? Sema::CXXCopyConstructor
: Sema::CXXCopyAssignment)
<< RD;
}
}
void Sema::DefineImplicitCopyAssignment(SourceLocation CurrentLocation,
CXXMethodDecl *CopyAssignOperator) {
assert((CopyAssignOperator->isDefaulted() &&
CopyAssignOperator->isOverloadedOperator() &&
CopyAssignOperator->getOverloadedOperator() == OO_Equal &&
!CopyAssignOperator->doesThisDeclarationHaveABody() &&
!CopyAssignOperator->isDeleted()) &&
"DefineImplicitCopyAssignment called for wrong function");
CXXRecordDecl *ClassDecl = CopyAssignOperator->getParent();
if (ClassDecl->isInvalidDecl() || CopyAssignOperator->isInvalidDecl()) {
CopyAssignOperator->setInvalidDecl();
return;
}
// C++11 [class.copy]p18:
// The [definition of an implicitly declared copy assignment operator] is
// deprecated if the class has a user-declared copy constructor or a
// user-declared destructor.
if (getLangOpts().CPlusPlus11 && CopyAssignOperator->isImplicit())
diagnoseDeprecatedCopyOperation(*this, CopyAssignOperator, CurrentLocation);
CopyAssignOperator->markUsed(Context);
SynthesizedFunctionScope Scope(*this, CopyAssignOperator);
DiagnosticErrorTrap Trap(Diags);
// C++0x [class.copy]p30:
// The implicitly-defined or explicitly-defaulted copy assignment operator
// for a non-union class X performs memberwise copy assignment of its
// subobjects. The direct base classes of X are assigned first, in the
// order of their declaration in the base-specifier-list, and then the
// immediate non-static data members of X are assigned, in the order in
// which they were declared in the class definition.
// The statements that form the synthesized function body.
SmallVector<Stmt*, 8> Statements;
// The parameter for the "other" object, which we are copying from.
ParmVarDecl *Other = CopyAssignOperator->getParamDecl(0);
Qualifiers OtherQuals = Other->getType().getQualifiers();
QualType OtherRefType = Other->getType();
if (const LValueReferenceType *OtherRef
= OtherRefType->getAs<LValueReferenceType>()) {
OtherRefType = OtherRef->getPointeeType();
OtherQuals = OtherRefType.getQualifiers();
}
// Our location for everything implicitly-generated.
SourceLocation Loc = CopyAssignOperator->getLocEnd().isValid()
? CopyAssignOperator->getLocEnd()
: CopyAssignOperator->getLocation();
// Builds a DeclRefExpr for the "other" object.
RefBuilder OtherRef(Other, OtherRefType);
// Builds the "this" pointer.
ThisBuilder This;
// Assign base classes.
bool Invalid = false;
for (auto &Base : ClassDecl->bases()) {
// Form the assignment:
// static_cast<Base*>(this)->Base::operator=(static_cast<Base&>(other));
QualType BaseType = Base.getType().getUnqualifiedType();
if (!BaseType->isRecordType()) {
Invalid = true;
continue;
}
CXXCastPath BasePath;
BasePath.push_back(&Base);
// Construct the "from" expression, which is an implicit cast to the
// appropriately-qualified base type.
CastBuilder From(OtherRef, Context.getQualifiedType(BaseType, OtherQuals),
VK_LValue, BasePath);
// Dereference "this".
DerefBuilder DerefThis(This);
CastBuilder To(DerefThis,
Context.getCVRQualifiedType(
BaseType, CopyAssignOperator->getTypeQualifiers()),
VK_LValue, BasePath);
// Build the copy.
StmtResult Copy = buildSingleCopyAssign(*this, Loc, BaseType,
To, From,
/*CopyingBaseSubobject=*/true,
/*Copying=*/true);
if (Copy.isInvalid()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
CopyAssignOperator->setInvalidDecl();
return;
}
// Success! Record the copy.
Statements.push_back(Copy.getAs<Expr>());
}
// Assign non-static members.
for (auto *Field : ClassDecl->fields()) {
if (Field->isUnnamedBitfield())
continue;
if (Field->isInvalidDecl()) {
Invalid = true;
continue;
}
// Check for members of reference type; we can't copy those.
if (Field->getType()->isReferenceType()) {
Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
<< Context.getTagDeclType(ClassDecl) << 0 << Field->getDeclName();
Diag(Field->getLocation(), diag::note_declared_at);
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
Invalid = true;
continue;
}
// Check for members of const-qualified, non-class type.
QualType BaseType = Context.getBaseElementType(Field->getType());
if (!BaseType->getAs<RecordType>() && BaseType.isConstQualified()) {
Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
<< Context.getTagDeclType(ClassDecl) << 1 << Field->getDeclName();
Diag(Field->getLocation(), diag::note_declared_at);
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
Invalid = true;
continue;
}
// Suppress assigning zero-width bitfields.
if (Field->isBitField() && Field->getBitWidthValue(Context) == 0)
continue;
QualType FieldType = Field->getType().getNonReferenceType();
if (FieldType->isIncompleteArrayType()) {
assert(ClassDecl->hasFlexibleArrayMember() &&
"Incomplete array type is not valid");
continue;
}
// Build references to the field in the object we're copying from and to.
CXXScopeSpec SS; // Intentionally empty
LookupResult MemberLookup(*this, Field->getDeclName(), Loc,
LookupMemberName);
MemberLookup.addDecl(Field);
MemberLookup.resolveKind();
MemberBuilder From(OtherRef, OtherRefType, /*IsArrow=*/false, MemberLookup);
MemberBuilder To(This, getCurrentThisType(), /*IsArrow=*/true, MemberLookup);
// Build the copy of this field.
StmtResult Copy = buildSingleCopyAssign(*this, Loc, FieldType,
To, From,
/*CopyingBaseSubobject=*/false,
/*Copying=*/true);
if (Copy.isInvalid()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
CopyAssignOperator->setInvalidDecl();
return;
}
// Success! Record the copy.
Statements.push_back(Copy.getAs<Stmt>());
}
if (!Invalid) {
// Add a "return *this;"
ExprResult ThisObj = CreateBuiltinUnaryOp(Loc, UO_Deref, This.build(*this, Loc));
StmtResult Return = BuildReturnStmt(Loc, ThisObj.get());
if (Return.isInvalid())
Invalid = true;
else {
Statements.push_back(Return.getAs<Stmt>());
if (Trap.hasErrorOccurred()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
Invalid = true;
}
}
}
if (Invalid) {
CopyAssignOperator->setInvalidDecl();
return;
}
StmtResult Body;
{
CompoundScopeRAII CompoundScope(*this);
Body = ActOnCompoundStmt(Loc, Loc, Statements,
/*isStmtExpr=*/false);
assert(!Body.isInvalid() && "Compound statement creation cannot fail");
}
CopyAssignOperator->setBody(Body.getAs<Stmt>());
if (ASTMutationListener *L = getASTMutationListener()) {
L->CompletedImplicitDefinition(CopyAssignOperator);
}
}
Sema::ImplicitExceptionSpecification
Sema::ComputeDefaultedMoveAssignmentExceptionSpec(CXXMethodDecl *MD) {
CXXRecordDecl *ClassDecl = MD->getParent();
ImplicitExceptionSpecification ExceptSpec(*this);
if (ClassDecl->isInvalidDecl())
return ExceptSpec;
// C++0x [except.spec]p14:
// An implicitly declared special member function (Clause 12) shall have an
// exception-specification. [...]
// It is unspecified whether or not an implicit move assignment operator
// attempts to deduplicate calls to assignment operators of virtual bases are
// made. As such, this exception specification is effectively unspecified.
// Based on a similar decision made for constness in C++0x, we're erring on
// the side of assuming such calls to be made regardless of whether they
// actually happen.
// Note that a move constructor is not implicitly declared when there are
// virtual bases, but it can still be user-declared and explicitly defaulted.
for (const auto &Base : ClassDecl->bases()) {
if (Base.isVirtual())
continue;
CXXRecordDecl *BaseClassDecl
= cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
if (CXXMethodDecl *MoveAssign = LookupMovingAssignment(BaseClassDecl,
0, false, 0))
ExceptSpec.CalledDecl(Base.getLocStart(), MoveAssign);
}
for (const auto &Base : ClassDecl->vbases()) {
CXXRecordDecl *BaseClassDecl
= cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
if (CXXMethodDecl *MoveAssign = LookupMovingAssignment(BaseClassDecl,
0, false, 0))
ExceptSpec.CalledDecl(Base.getLocStart(), MoveAssign);
}
for (const auto *Field : ClassDecl->fields()) {
QualType FieldType = Context.getBaseElementType(Field->getType());
if (CXXRecordDecl *FieldClassDecl = FieldType->getAsCXXRecordDecl()) {
if (CXXMethodDecl *MoveAssign =
LookupMovingAssignment(FieldClassDecl,
FieldType.getCVRQualifiers(),
false, 0))
ExceptSpec.CalledDecl(Field->getLocation(), MoveAssign);
}
}
return ExceptSpec;
}
CXXMethodDecl *Sema::DeclareImplicitMoveAssignment(CXXRecordDecl *ClassDecl) {
assert(ClassDecl->needsImplicitMoveAssignment());
DeclaringSpecialMember DSM(*this, ClassDecl, CXXMoveAssignment);
if (DSM.isAlreadyBeingDeclared())
return nullptr;
// Note: The following rules are largely analoguous to the move
// constructor rules.
QualType ArgType = Context.getTypeDeclType(ClassDecl);
QualType RetType = Context.getLValueReferenceType(ArgType);
ArgType = Context.getRValueReferenceType(ArgType);
bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
CXXMoveAssignment,
false);
// An implicitly-declared move assignment operator is an inline public
// member of its class.
DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
SourceLocation ClassLoc = ClassDecl->getLocation();
DeclarationNameInfo NameInfo(Name, ClassLoc);
CXXMethodDecl *MoveAssignment =
CXXMethodDecl::Create(Context, ClassDecl, ClassLoc, NameInfo, QualType(),
/*TInfo=*/nullptr, /*StorageClass=*/SC_None,
/*isInline=*/true, Constexpr, SourceLocation());
MoveAssignment->setAccess(AS_public);
MoveAssignment->setDefaulted();
MoveAssignment->setImplicit();
// Build an exception specification pointing back at this member.
FunctionProtoType::ExtProtoInfo EPI =
getImplicitMethodEPI(*this, MoveAssignment);
MoveAssignment->setType(Context.getFunctionType(RetType, ArgType, EPI));
// Add the parameter to the operator.
ParmVarDecl *FromParam = ParmVarDecl::Create(Context, MoveAssignment,
ClassLoc, ClassLoc,
/*Id=*/nullptr, ArgType,
/*TInfo=*/nullptr, SC_None,
nullptr);
MoveAssignment->setParams(FromParam);
AddOverriddenMethods(ClassDecl, MoveAssignment);
MoveAssignment->setTrivial(
ClassDecl->needsOverloadResolutionForMoveAssignment()
? SpecialMemberIsTrivial(MoveAssignment, CXXMoveAssignment)
: ClassDecl->hasTrivialMoveAssignment());
if (ShouldDeleteSpecialMember(MoveAssignment, CXXMoveAssignment)) {
ClassDecl->setImplicitMoveAssignmentIsDeleted();
SetDeclDeleted(MoveAssignment, ClassLoc);
}
// Note that we have added this copy-assignment operator.
++ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
if (Scope *S = getScopeForContext(ClassDecl))
PushOnScopeChains(MoveAssignment, S, false);
ClassDecl->addDecl(MoveAssignment);
return MoveAssignment;
}
/// Check if we're implicitly defining a move assignment operator for a class
/// with virtual bases. Such a move assignment might move-assign the virtual
/// base multiple times.
static void checkMoveAssignmentForRepeatedMove(Sema &S, CXXRecordDecl *Class,
SourceLocation CurrentLocation) {
assert(!Class->isDependentContext() && "should not define dependent move");
// Only a virtual base could get implicitly move-assigned multiple times.
// Only a non-trivial move assignment can observe this. We only want to
// diagnose if we implicitly define an assignment operator that assigns
// two base classes, both of which move-assign the same virtual base.
if (Class->getNumVBases() == 0 || Class->hasTrivialMoveAssignment() ||
Class->getNumBases() < 2)
return;
llvm::SmallVector<CXXBaseSpecifier *, 16> Worklist;
typedef llvm::DenseMap<CXXRecordDecl*, CXXBaseSpecifier*> VBaseMap;
VBaseMap VBases;
for (auto &BI : Class->bases()) {
Worklist.push_back(&BI);
while (!Worklist.empty()) {
CXXBaseSpecifier *BaseSpec = Worklist.pop_back_val();
CXXRecordDecl *Base = BaseSpec->getType()->getAsCXXRecordDecl();
// If the base has no non-trivial move assignment operators,
// we don't care about moves from it.
if (!Base->hasNonTrivialMoveAssignment())
continue;
// If there's nothing virtual here, skip it.
if (!BaseSpec->isVirtual() && !Base->getNumVBases())
continue;
// If we're not actually going to call a move assignment for this base,
// or the selected move assignment is trivial, skip it.
Sema::SpecialMemberOverloadResult *SMOR =
S.LookupSpecialMember(Base, Sema::CXXMoveAssignment,
/*ConstArg*/false, /*VolatileArg*/false,
/*RValueThis*/true, /*ConstThis*/false,
/*VolatileThis*/false);
if (!SMOR->getMethod() || SMOR->getMethod()->isTrivial() ||
!SMOR->getMethod()->isMoveAssignmentOperator())
continue;
if (BaseSpec->isVirtual()) {
// We're going to move-assign this virtual base, and its move
// assignment operator is not trivial. If this can happen for
// multiple distinct direct bases of Class, diagnose it. (If it
// only happens in one base, we'll diagnose it when synthesizing
// that base class's move assignment operator.)
CXXBaseSpecifier *&Existing =
VBases.insert(std::make_pair(Base->getCanonicalDecl(), &BI))
.first->second;
if (Existing && Existing != &BI) {
S.Diag(CurrentLocation, diag::warn_vbase_moved_multiple_times)
<< Class << Base;
S.Diag(Existing->getLocStart(), diag::note_vbase_moved_here)
<< (Base->getCanonicalDecl() ==
Existing->getType()->getAsCXXRecordDecl()->getCanonicalDecl())
<< Base << Existing->getType() << Existing->getSourceRange();
S.Diag(BI.getLocStart(), diag::note_vbase_moved_here)
<< (Base->getCanonicalDecl() ==
BI.getType()->getAsCXXRecordDecl()->getCanonicalDecl())
<< Base << BI.getType() << BaseSpec->getSourceRange();
// Only diagnose each vbase once.
Existing = nullptr;
}
} else {
// Only walk over bases that have defaulted move assignment operators.
// We assume that any user-provided move assignment operator handles
// the multiple-moves-of-vbase case itself somehow.
if (!SMOR->getMethod()->isDefaulted())
continue;
// We're going to move the base classes of Base. Add them to the list.
for (auto &BI : Base->bases())
Worklist.push_back(&BI);
}
}
}
}
void Sema::DefineImplicitMoveAssignment(SourceLocation CurrentLocation,
CXXMethodDecl *MoveAssignOperator) {
assert((MoveAssignOperator->isDefaulted() &&
MoveAssignOperator->isOverloadedOperator() &&
MoveAssignOperator->getOverloadedOperator() == OO_Equal &&
!MoveAssignOperator->doesThisDeclarationHaveABody() &&
!MoveAssignOperator->isDeleted()) &&
"DefineImplicitMoveAssignment called for wrong function");
CXXRecordDecl *ClassDecl = MoveAssignOperator->getParent();
if (ClassDecl->isInvalidDecl() || MoveAssignOperator->isInvalidDecl()) {
MoveAssignOperator->setInvalidDecl();
return;
}
MoveAssignOperator->markUsed(Context);
SynthesizedFunctionScope Scope(*this, MoveAssignOperator);
DiagnosticErrorTrap Trap(Diags);
// C++0x [class.copy]p28:
// The implicitly-defined or move assignment operator for a non-union class
// X performs memberwise move assignment of its subobjects. The direct base
// classes of X are assigned first, in the order of their declaration in the
// base-specifier-list, and then the immediate non-static data members of X
// are assigned, in the order in which they were declared in the class
// definition.
// Issue a warning if our implicit move assignment operator will move
// from a virtual base more than once.
checkMoveAssignmentForRepeatedMove(*this, ClassDecl, CurrentLocation);
// The statements that form the synthesized function body.
SmallVector<Stmt*, 8> Statements;
// The parameter for the "other" object, which we are move from.
ParmVarDecl *Other = MoveAssignOperator->getParamDecl(0);
QualType OtherRefType = Other->getType()->
getAs<RValueReferenceType>()->getPointeeType();
assert(!OtherRefType.getQualifiers() &&
"Bad argument type of defaulted move assignment");
// Our location for everything implicitly-generated.
SourceLocation Loc = MoveAssignOperator->getLocEnd().isValid()
? MoveAssignOperator->getLocEnd()
: MoveAssignOperator->getLocation();
// Builds a reference to the "other" object.
RefBuilder OtherRef(Other, OtherRefType);
// Cast to rvalue.
MoveCastBuilder MoveOther(OtherRef);
// Builds the "this" pointer.
ThisBuilder This;
// Assign base classes.
bool Invalid = false;
for (auto &Base : ClassDecl->bases()) {
// C++11 [class.copy]p28:
// It is unspecified whether subobjects representing virtual base classes
// are assigned more than once by the implicitly-defined copy assignment
// operator.
// FIXME: Do not assign to a vbase that will be assigned by some other base
// class. For a move-assignment, this can result in the vbase being moved
// multiple times.
// Form the assignment:
// static_cast<Base*>(this)->Base::operator=(static_cast<Base&&>(other));
QualType BaseType = Base.getType().getUnqualifiedType();
if (!BaseType->isRecordType()) {
Invalid = true;
continue;
}
CXXCastPath BasePath;
BasePath.push_back(&Base);
// Construct the "from" expression, which is an implicit cast to the
// appropriately-qualified base type.
CastBuilder From(OtherRef, BaseType, VK_XValue, BasePath);
// Dereference "this".
DerefBuilder DerefThis(This);
// Implicitly cast "this" to the appropriately-qualified base type.
CastBuilder To(DerefThis,
Context.getCVRQualifiedType(
BaseType, MoveAssignOperator->getTypeQualifiers()),
VK_LValue, BasePath);
// Build the move.
StmtResult Move = buildSingleCopyAssign(*this, Loc, BaseType,
To, From,
/*CopyingBaseSubobject=*/true,
/*Copying=*/false);
if (Move.isInvalid()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
MoveAssignOperator->setInvalidDecl();
return;
}
// Success! Record the move.
Statements.push_back(Move.getAs<Expr>());
}
// Assign non-static members.
for (auto *Field : ClassDecl->fields()) {
if (Field->isUnnamedBitfield())
continue;
if (Field->isInvalidDecl()) {
Invalid = true;
continue;
}
// Check for members of reference type; we can't move those.
if (Field->getType()->isReferenceType()) {
Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
<< Context.getTagDeclType(ClassDecl) << 0 << Field->getDeclName();
Diag(Field->getLocation(), diag::note_declared_at);
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
Invalid = true;
continue;
}
// Check for members of const-qualified, non-class type.
QualType BaseType = Context.getBaseElementType(Field->getType());
if (!BaseType->getAs<RecordType>() && BaseType.isConstQualified()) {
Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
<< Context.getTagDeclType(ClassDecl) << 1 << Field->getDeclName();
Diag(Field->getLocation(), diag::note_declared_at);
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
Invalid = true;
continue;
}
// Suppress assigning zero-width bitfields.
if (Field->isBitField() && Field->getBitWidthValue(Context) == 0)
continue;
QualType FieldType = Field->getType().getNonReferenceType();
if (FieldType->isIncompleteArrayType()) {
assert(ClassDecl->hasFlexibleArrayMember() &&
"Incomplete array type is not valid");
continue;
}
// Build references to the field in the object we're copying from and to.
LookupResult MemberLookup(*this, Field->getDeclName(), Loc,
LookupMemberName);
MemberLookup.addDecl(Field);
MemberLookup.resolveKind();
MemberBuilder From(MoveOther, OtherRefType,
/*IsArrow=*/false, MemberLookup);
MemberBuilder To(This, getCurrentThisType(),
/*IsArrow=*/true, MemberLookup);
assert(!From.build(*this, Loc)->isLValue() && // could be xvalue or prvalue
"Member reference with rvalue base must be rvalue except for reference "
"members, which aren't allowed for move assignment.");
// Build the move of this field.
StmtResult Move = buildSingleCopyAssign(*this, Loc, FieldType,
To, From,
/*CopyingBaseSubobject=*/false,
/*Copying=*/false);
if (Move.isInvalid()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
MoveAssignOperator->setInvalidDecl();
return;
}
// Success! Record the copy.
Statements.push_back(Move.getAs<Stmt>());
}
if (!Invalid) {
// Add a "return *this;"
ExprResult ThisObj =
CreateBuiltinUnaryOp(Loc, UO_Deref, This.build(*this, Loc));
StmtResult Return = BuildReturnStmt(Loc, ThisObj.get());
if (Return.isInvalid())
Invalid = true;
else {
Statements.push_back(Return.getAs<Stmt>());
if (Trap.hasErrorOccurred()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
Invalid = true;
}
}
}
if (Invalid) {
MoveAssignOperator->setInvalidDecl();
return;
}
StmtResult Body;
{
CompoundScopeRAII CompoundScope(*this);
Body = ActOnCompoundStmt(Loc, Loc, Statements,
/*isStmtExpr=*/false);
assert(!Body.isInvalid() && "Compound statement creation cannot fail");
}
MoveAssignOperator->setBody(Body.getAs<Stmt>());
if (ASTMutationListener *L = getASTMutationListener()) {
L->CompletedImplicitDefinition(MoveAssignOperator);
}
}
Sema::ImplicitExceptionSpecification
Sema::ComputeDefaultedCopyCtorExceptionSpec(CXXMethodDecl *MD) {
CXXRecordDecl *ClassDecl = MD->getParent();
ImplicitExceptionSpecification ExceptSpec(*this);
if (ClassDecl->isInvalidDecl())
return ExceptSpec;
const FunctionProtoType *T = MD->getType()->castAs<FunctionProtoType>();
assert(T->getNumParams() >= 1 && "not a copy ctor");
unsigned Quals = T->getParamType(0).getNonReferenceType().getCVRQualifiers();
// C++ [except.spec]p14:
// An implicitly declared special member function (Clause 12) shall have an
// exception-specification. [...]
for (const auto &Base : ClassDecl->bases()) {
// Virtual bases are handled below.
if (Base.isVirtual())
continue;
CXXRecordDecl *BaseClassDecl
= cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
if (CXXConstructorDecl *CopyConstructor =
LookupCopyingConstructor(BaseClassDecl, Quals))
ExceptSpec.CalledDecl(Base.getLocStart(), CopyConstructor);
}
for (const auto &Base : ClassDecl->vbases()) {
CXXRecordDecl *BaseClassDecl
= cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
if (CXXConstructorDecl *CopyConstructor =
LookupCopyingConstructor(BaseClassDecl, Quals))
ExceptSpec.CalledDecl(Base.getLocStart(), CopyConstructor);
}
for (const auto *Field : ClassDecl->fields()) {
QualType FieldType = Context.getBaseElementType(Field->getType());
if (CXXRecordDecl *FieldClassDecl = FieldType->getAsCXXRecordDecl()) {
if (CXXConstructorDecl *CopyConstructor =
LookupCopyingConstructor(FieldClassDecl,
Quals | FieldType.getCVRQualifiers()))
ExceptSpec.CalledDecl(Field->getLocation(), CopyConstructor);
}
}
return ExceptSpec;
}
CXXConstructorDecl *Sema::DeclareImplicitCopyConstructor(
CXXRecordDecl *ClassDecl) {
// C++ [class.copy]p4:
// If the class definition does not explicitly declare a copy
// constructor, one is declared implicitly.
assert(ClassDecl->needsImplicitCopyConstructor());
DeclaringSpecialMember DSM(*this, ClassDecl, CXXCopyConstructor);
if (DSM.isAlreadyBeingDeclared())
return nullptr;
QualType ClassType = Context.getTypeDeclType(ClassDecl);
QualType ArgType = ClassType;
bool Const = ClassDecl->implicitCopyConstructorHasConstParam();
if (Const)
ArgType = ArgType.withConst();
ArgType = Context.getLValueReferenceType(ArgType);
bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
CXXCopyConstructor,
Const);
DeclarationName Name
= Context.DeclarationNames.getCXXConstructorName(
Context.getCanonicalType(ClassType));
SourceLocation ClassLoc = ClassDecl->getLocation();
DeclarationNameInfo NameInfo(Name, ClassLoc);
// An implicitly-declared copy constructor is an inline public
// member of its class.
CXXConstructorDecl *CopyConstructor = CXXConstructorDecl::Create(
Context, ClassDecl, ClassLoc, NameInfo, QualType(), /*TInfo=*/nullptr,
/*isExplicit=*/false, /*isInline=*/true, /*isImplicitlyDeclared=*/true,
Constexpr);
CopyConstructor->setAccess(AS_public);
CopyConstructor->setDefaulted();
// Build an exception specification pointing back at this member.
FunctionProtoType::ExtProtoInfo EPI =
getImplicitMethodEPI(*this, CopyConstructor);
CopyConstructor->setType(
Context.getFunctionType(Context.VoidTy, ArgType, EPI));
// Add the parameter to the constructor.
ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor,
ClassLoc, ClassLoc,
/*IdentifierInfo=*/nullptr,
ArgType, /*TInfo=*/nullptr,
SC_None, nullptr);
CopyConstructor->setParams(FromParam);
CopyConstructor->setTrivial(
ClassDecl->needsOverloadResolutionForCopyConstructor()
? SpecialMemberIsTrivial(CopyConstructor, CXXCopyConstructor)
: ClassDecl->hasTrivialCopyConstructor());
if (ShouldDeleteSpecialMember(CopyConstructor, CXXCopyConstructor))
SetDeclDeleted(CopyConstructor, ClassLoc);
// Note that we have declared this constructor.
++ASTContext::NumImplicitCopyConstructorsDeclared;
if (Scope *S = getScopeForContext(ClassDecl))
PushOnScopeChains(CopyConstructor, S, false);
ClassDecl->addDecl(CopyConstructor);
return CopyConstructor;
}
void Sema::DefineImplicitCopyConstructor(SourceLocation CurrentLocation,
CXXConstructorDecl *CopyConstructor) {
assert((CopyConstructor->isDefaulted() &&
CopyConstructor->isCopyConstructor() &&
!CopyConstructor->doesThisDeclarationHaveABody() &&
!CopyConstructor->isDeleted()) &&
"DefineImplicitCopyConstructor - call it for implicit copy ctor");
CXXRecordDecl *ClassDecl = CopyConstructor->getParent();
assert(ClassDecl && "DefineImplicitCopyConstructor - invalid constructor");
// C++11 [class.copy]p7:
// The [definition of an implicitly declared copy constructor] is
// deprecated if the class has a user-declared copy assignment operator
// or a user-declared destructor.
if (getLangOpts().CPlusPlus11 && CopyConstructor->isImplicit())
diagnoseDeprecatedCopyOperation(*this, CopyConstructor, CurrentLocation);
SynthesizedFunctionScope Scope(*this, CopyConstructor);
DiagnosticErrorTrap Trap(Diags);
if (SetCtorInitializers(CopyConstructor, /*AnyErrors=*/false) ||
Trap.hasErrorOccurred()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXCopyConstructor << Context.getTagDeclType(ClassDecl);
CopyConstructor->setInvalidDecl();
} else {
SourceLocation Loc = CopyConstructor->getLocEnd().isValid()
? CopyConstructor->getLocEnd()
: CopyConstructor->getLocation();
Sema::CompoundScopeRAII CompoundScope(*this);
CopyConstructor->setBody(
ActOnCompoundStmt(Loc, Loc, None, /*isStmtExpr=*/false).getAs<Stmt>());
}
CopyConstructor->markUsed(Context);
if (ASTMutationListener *L = getASTMutationListener()) {
L->CompletedImplicitDefinition(CopyConstructor);
}
}
Sema::ImplicitExceptionSpecification
Sema::ComputeDefaultedMoveCtorExceptionSpec(CXXMethodDecl *MD) {
CXXRecordDecl *ClassDecl = MD->getParent();
// C++ [except.spec]p14:
// An implicitly declared special member function (Clause 12) shall have an
// exception-specification. [...]
ImplicitExceptionSpecification ExceptSpec(*this);
if (ClassDecl->isInvalidDecl())
return ExceptSpec;
// Direct base-class constructors.
for (const auto &B : ClassDecl->bases()) {
if (B.isVirtual()) // Handled below.
continue;
if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
CXXConstructorDecl *Constructor =
LookupMovingConstructor(BaseClassDecl, 0);
// If this is a deleted function, add it anyway. This might be conformant
// with the standard. This might not. I'm not sure. It might not matter.
if (Constructor)
ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
}
}
// Virtual base-class constructors.
for (const auto &B : ClassDecl->vbases()) {
if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
CXXConstructorDecl *Constructor =
LookupMovingConstructor(BaseClassDecl, 0);
// If this is a deleted function, add it anyway. This might be conformant
// with the standard. This might not. I'm not sure. It might not matter.
if (Constructor)
ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
}
}
// Field constructors.
for (const auto *F : ClassDecl->fields()) {
QualType FieldType = Context.getBaseElementType(F->getType());
if (CXXRecordDecl *FieldRecDecl = FieldType->getAsCXXRecordDecl()) {
CXXConstructorDecl *Constructor =
LookupMovingConstructor(FieldRecDecl, FieldType.getCVRQualifiers());
// If this is a deleted function, add it anyway. This might be conformant
// with the standard. This might not. I'm not sure. It might not matter.
// In particular, the problem is that this function never gets called. It
// might just be ill-formed because this function attempts to refer to
// a deleted function here.
if (Constructor)
ExceptSpec.CalledDecl(F->getLocation(), Constructor);
}
}
return ExceptSpec;
}
CXXConstructorDecl *Sema::DeclareImplicitMoveConstructor(
CXXRecordDecl *ClassDecl) {
assert(ClassDecl->needsImplicitMoveConstructor());
DeclaringSpecialMember DSM(*this, ClassDecl, CXXMoveConstructor);
if (DSM.isAlreadyBeingDeclared())
return nullptr;
QualType ClassType = Context.getTypeDeclType(ClassDecl);
QualType ArgType = Context.getRValueReferenceType(ClassType);
bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
CXXMoveConstructor,
false);
DeclarationName Name
= Context.DeclarationNames.getCXXConstructorName(
Context.getCanonicalType(ClassType));
SourceLocation ClassLoc = ClassDecl->getLocation();
DeclarationNameInfo NameInfo(Name, ClassLoc);
// C++11 [class.copy]p11:
// An implicitly-declared copy/move constructor is an inline public
// member of its class.
CXXConstructorDecl *MoveConstructor = CXXConstructorDecl::Create(
Context, ClassDecl, ClassLoc, NameInfo, QualType(), /*TInfo=*/nullptr,
/*isExplicit=*/false, /*isInline=*/true, /*isImplicitlyDeclared=*/true,
Constexpr);
MoveConstructor->setAccess(AS_public);
MoveConstructor->setDefaulted();
// Build an exception specification pointing back at this member.
FunctionProtoType::ExtProtoInfo EPI =
getImplicitMethodEPI(*this, MoveConstructor);
MoveConstructor->setType(
Context.getFunctionType(Context.VoidTy, ArgType, EPI));
// Add the parameter to the constructor.
ParmVarDecl *FromParam = ParmVarDecl::Create(Context, MoveConstructor,
ClassLoc, ClassLoc,
/*IdentifierInfo=*/nullptr,
ArgType, /*TInfo=*/nullptr,
SC_None, nullptr);
MoveConstructor->setParams(FromParam);
MoveConstructor->setTrivial(
ClassDecl->needsOverloadResolutionForMoveConstructor()
? SpecialMemberIsTrivial(MoveConstructor, CXXMoveConstructor)
: ClassDecl->hasTrivialMoveConstructor());
if (ShouldDeleteSpecialMember(MoveConstructor, CXXMoveConstructor)) {
ClassDecl->setImplicitMoveConstructorIsDeleted();
SetDeclDeleted(MoveConstructor, ClassLoc);
}
// Note that we have declared this constructor.
++ASTContext::NumImplicitMoveConstructorsDeclared;
if (Scope *S = getScopeForContext(ClassDecl))
PushOnScopeChains(MoveConstructor, S, false);
ClassDecl->addDecl(MoveConstructor);
return MoveConstructor;
}
void Sema::DefineImplicitMoveConstructor(SourceLocation CurrentLocation,
CXXConstructorDecl *MoveConstructor) {
assert((MoveConstructor->isDefaulted() &&
MoveConstructor->isMoveConstructor() &&
!MoveConstructor->doesThisDeclarationHaveABody() &&
!MoveConstructor->isDeleted()) &&
"DefineImplicitMoveConstructor - call it for implicit move ctor");
CXXRecordDecl *ClassDecl = MoveConstructor->getParent();
assert(ClassDecl && "DefineImplicitMoveConstructor - invalid constructor");
SynthesizedFunctionScope Scope(*this, MoveConstructor);
DiagnosticErrorTrap Trap(Diags);
if (SetCtorInitializers(MoveConstructor, /*AnyErrors=*/false) ||
Trap.hasErrorOccurred()) {
Diag(CurrentLocation, diag::note_member_synthesized_at)
<< CXXMoveConstructor << Context.getTagDeclType(ClassDecl);
MoveConstructor->setInvalidDecl();
} else {
SourceLocation Loc = MoveConstructor->getLocEnd().isValid()
? MoveConstructor->getLocEnd()
: MoveConstructor->getLocation();
Sema::CompoundScopeRAII CompoundScope(*this);
MoveConstructor->setBody(ActOnCompoundStmt(
Loc, Loc, None, /*isStmtExpr=*/ false).getAs<Stmt>());
}
MoveConstructor->markUsed(Context);
if (ASTMutationListener *L = getASTMutationListener()) {
L->CompletedImplicitDefinition(MoveConstructor);
}
}
bool Sema::isImplicitlyDeleted(FunctionDecl *FD) {
return FD->isDeleted() && FD->isDefaulted() && isa<CXXMethodDecl>(FD);
}
void Sema::DefineImplicitLambdaToFunctionPointerConversion(
SourceLocation CurrentLocation,
CXXConversionDecl *Conv) {
CXXRecordDecl *Lambda = Conv->getParent();
CXXMethodDecl *CallOp = Lambda->getLambdaCallOperator();
// If we are defining a specialization of a conversion to function-ptr
// cache the deduced template arguments for this specialization
// so that we can use them to retrieve the corresponding call-operator
// and static-invoker.
const TemplateArgumentList *DeducedTemplateArgs = nullptr;
// Retrieve the corresponding call-operator specialization.
if (Lambda->isGenericLambda()) {
assert(Conv->isFunctionTemplateSpecialization());
FunctionTemplateDecl *CallOpTemplate =
CallOp->getDescribedFunctionTemplate();
DeducedTemplateArgs = Conv->getTemplateSpecializationArgs();
void *InsertPos = nullptr;
FunctionDecl *CallOpSpec = CallOpTemplate->findSpecialization(
DeducedTemplateArgs->asArray(),
InsertPos);
assert(CallOpSpec &&
"Conversion operator must have a corresponding call operator");
CallOp = cast<CXXMethodDecl>(CallOpSpec);
}
// Mark the call operator referenced (and add to pending instantiations
// if necessary).
// For both the conversion and static-invoker template specializations
// we construct their body's in this function, so no need to add them
// to the PendingInstantiations.
MarkFunctionReferenced(CurrentLocation, CallOp);
SynthesizedFunctionScope Scope(*this, Conv);
DiagnosticErrorTrap Trap(Diags);
// Retrieve the static invoker...
CXXMethodDecl *Invoker = Lambda->getLambdaStaticInvoker();
// ... and get the corresponding specialization for a generic lambda.
if (Lambda->isGenericLambda()) {
assert(DeducedTemplateArgs &&
"Must have deduced template arguments from Conversion Operator");
FunctionTemplateDecl *InvokeTemplate =
Invoker->getDescribedFunctionTemplate();
void *InsertPos = nullptr;
FunctionDecl *InvokeSpec = InvokeTemplate->findSpecialization(
DeducedTemplateArgs->asArray(),
InsertPos);
assert(InvokeSpec &&
"Must have a corresponding static invoker specialization");
Invoker = cast<CXXMethodDecl>(InvokeSpec);
}
// Construct the body of the conversion function { return __invoke; }.
Expr *FunctionRef = BuildDeclRefExpr(Invoker, Invoker->getType(),
VK_LValue, Conv->getLocation()).get();
assert(FunctionRef && "Can't refer to __invoke function?");
Stmt *Return = BuildReturnStmt(Conv->getLocation(), FunctionRef).get();
Conv->setBody(new (Context) CompoundStmt(Context, Return,
Conv->getLocation(),
Conv->getLocation()));
Conv->markUsed(Context);
Conv->setReferenced();
// Fill in the __invoke function with a dummy implementation. IR generation
// will fill in the actual details.
Invoker->markUsed(Context);
Invoker->setReferenced();
Invoker->setBody(new (Context) CompoundStmt(Conv->getLocation()));
if (ASTMutationListener *L = getASTMutationListener()) {
L->CompletedImplicitDefinition(Conv);
L->CompletedImplicitDefinition(Invoker);
}
}
void Sema::DefineImplicitLambdaToBlockPointerConversion(
SourceLocation CurrentLocation,
CXXConversionDecl *Conv)
{
assert(!Conv->getParent()->isGenericLambda());
Conv->markUsed(Context);
SynthesizedFunctionScope Scope(*this, Conv);
DiagnosticErrorTrap Trap(Diags);
// Copy-initialize the lambda object as needed to capture it.
Expr *This = ActOnCXXThis(CurrentLocation).get();
Expr *DerefThis =CreateBuiltinUnaryOp(CurrentLocation, UO_Deref, This).get();
ExprResult BuildBlock = BuildBlockForLambdaConversion(CurrentLocation,
Conv->getLocation(),
Conv, DerefThis);
// If we're not under ARC, make sure we still get the _Block_copy/autorelease
// behavior. Note that only the general conversion function does this
// (since it's unusable otherwise); in the case where we inline the
// block literal, it has block literal lifetime semantics.
if (!BuildBlock.isInvalid() && !getLangOpts().ObjCAutoRefCount)
BuildBlock = ImplicitCastExpr::Create(Context, BuildBlock.get()->getType(),
CK_CopyAndAutoreleaseBlockObject,
BuildBlock.get(), nullptr, VK_RValue);
if (BuildBlock.isInvalid()) {
Diag(CurrentLocation, diag::note_lambda_to_block_conv);
Conv->setInvalidDecl();
return;
}
// Create the return statement that returns the block from the conversion
// function.
StmtResult Return = BuildReturnStmt(Conv->getLocation(), BuildBlock.get());
if (Return.isInvalid()) {
Diag(CurrentLocation, diag::note_lambda_to_block_conv);
Conv->setInvalidDecl();
return;
}
// Set the body of the conversion function.
Stmt *ReturnS = Return.get();
Conv->setBody(new (Context) CompoundStmt(Context, ReturnS,
Conv->getLocation(),
Conv->getLocation()));
// We're done; notify the mutation listener, if any.
if (ASTMutationListener *L = getASTMutationListener()) {
L->CompletedImplicitDefinition(Conv);
}
}
/// \brief Determine whether the given list arguments contains exactly one
/// "real" (non-default) argument.
static bool hasOneRealArgument(MultiExprArg Args) {
switch (Args.size()) {
case 0:
return false;
default:
if (!Args[1]->isDefaultArgument())
return false;
// fall through
case 1:
return !Args[0]->isDefaultArgument();
}
return false;
}
ExprResult
Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
CXXConstructorDecl *Constructor,
MultiExprArg ExprArgs,
bool HadMultipleCandidates,
bool IsListInitialization,
bool RequiresZeroInit,
unsigned ConstructKind,
SourceRange ParenRange) {
bool Elidable = false;
// C++0x [class.copy]p34:
// When certain criteria are met, an implementation is allowed to
// omit the copy/move construction of a class object, even if the
// copy/move constructor and/or destructor for the object have
// side effects. [...]
// - when a temporary class object that has not been bound to a
// reference (12.2) would be copied/moved to a class object
// with the same cv-unqualified type, the copy/move operation
// can be omitted by constructing the temporary object
// directly into the target of the omitted copy/move
if (ConstructKind == CXXConstructExpr::CK_Complete &&
Constructor->isCopyOrMoveConstructor() && hasOneRealArgument(ExprArgs)) {
Expr *SubExpr = ExprArgs[0];
Elidable = SubExpr->isTemporaryObject(Context, Constructor->getParent());
}
return BuildCXXConstructExpr(ConstructLoc, DeclInitType, Constructor,
Elidable, ExprArgs, HadMultipleCandidates,
IsListInitialization, RequiresZeroInit,
ConstructKind, ParenRange);
}
/// BuildCXXConstructExpr - Creates a complete call to a constructor,
/// including handling of its default argument expressions.
ExprResult
Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
CXXConstructorDecl *Constructor, bool Elidable,
MultiExprArg ExprArgs,
bool HadMultipleCandidates,
bool IsListInitialization,
bool RequiresZeroInit,
unsigned ConstructKind,
SourceRange ParenRange) {
MarkFunctionReferenced(ConstructLoc, Constructor);
return CXXConstructExpr::Create(
Context, DeclInitType, ConstructLoc, Constructor, Elidable, ExprArgs,
HadMultipleCandidates, IsListInitialization, RequiresZeroInit,
static_cast<CXXConstructExpr::ConstructionKind>(ConstructKind),
ParenRange);
}
void Sema::FinalizeVarWithDestructor(VarDecl *VD, const RecordType *Record) {
if (VD->isInvalidDecl()) return;
CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Record->getDecl());
if (ClassDecl->isInvalidDecl()) return;
if (ClassDecl->hasIrrelevantDestructor()) return;
if (ClassDecl->isDependentContext()) return;
CXXDestructorDecl *Destructor = LookupDestructor(ClassDecl);
MarkFunctionReferenced(VD->getLocation(), Destructor);
CheckDestructorAccess(VD->getLocation(), Destructor,
PDiag(diag::err_access_dtor_var)
<< VD->getDeclName()
<< VD->getType());
DiagnoseUseOfDecl(Destructor, VD->getLocation());
if (Destructor->isTrivial()) return;
if (!VD->hasGlobalStorage()) return;
// Emit warning for non-trivial dtor in global scope (a real global,
// class-static, function-static).
Diag(VD->getLocation(), diag::warn_exit_time_destructor);
// TODO: this should be re-enabled for static locals by !CXAAtExit
if (!VD->isStaticLocal())
Diag(VD->getLocation(), diag::warn_global_destructor);
}
/// \brief Given a constructor and the set of arguments provided for the
/// constructor, convert the arguments and add any required default arguments
/// to form a proper call to this constructor.
///
/// \returns true if an error occurred, false otherwise.
bool
Sema::CompleteConstructorCall(CXXConstructorDecl *Constructor,
MultiExprArg ArgsPtr,
SourceLocation Loc,
SmallVectorImpl<Expr*> &ConvertedArgs,
bool AllowExplicit,
bool IsListInitialization) {
// FIXME: This duplicates a lot of code from Sema::ConvertArgumentsForCall.
unsigned NumArgs = ArgsPtr.size();
Expr **Args = ArgsPtr.data();
const FunctionProtoType *Proto
= Constructor->getType()->getAs<FunctionProtoType>();
assert(Proto && "Constructor without a prototype?");
unsigned NumParams = Proto->getNumParams();
// If too few arguments are available, we'll fill in the rest with defaults.
if (NumArgs < NumParams)
ConvertedArgs.reserve(NumParams);
else
ConvertedArgs.reserve(NumArgs);
VariadicCallType CallType =
Proto->isVariadic() ? VariadicConstructor : VariadicDoesNotApply;
SmallVector<Expr *, 8> AllArgs;
bool Invalid = GatherArgumentsForCall(Loc, Constructor,
Proto, 0,
llvm::makeArrayRef(Args, NumArgs),
AllArgs,
CallType, AllowExplicit,
IsListInitialization);
ConvertedArgs.append(AllArgs.begin(), AllArgs.end());
DiagnoseSentinelCalls(Constructor, Loc, AllArgs);
CheckConstructorCall(Constructor,
llvm::makeArrayRef<const Expr *>(AllArgs.data(),
AllArgs.size()),
Proto, Loc);
return Invalid;
}
static inline bool
CheckOperatorNewDeleteDeclarationScope(Sema &SemaRef,
const FunctionDecl *FnDecl) {
const DeclContext *DC = FnDecl->getDeclContext()->getRedeclContext();
if (isa<NamespaceDecl>(DC)) {
return SemaRef.Diag(FnDecl->getLocation(),
diag::err_operator_new_delete_declared_in_namespace)
<< FnDecl->getDeclName();
}
if (isa<TranslationUnitDecl>(DC) &&
FnDecl->getStorageClass() == SC_Static) {
return SemaRef.Diag(FnDecl->getLocation(),
diag::err_operator_new_delete_declared_static)
<< FnDecl->getDeclName();
}
return false;
}
static inline bool
CheckOperatorNewDeleteTypes(Sema &SemaRef, const FunctionDecl *FnDecl,
CanQualType ExpectedResultType,
CanQualType ExpectedFirstParamType,
unsigned DependentParamTypeDiag,
unsigned InvalidParamTypeDiag) {
QualType ResultType =
FnDecl->getType()->getAs<FunctionType>()->getReturnType();
// Check that the result type is not dependent.
if (ResultType->isDependentType())
return SemaRef.Diag(FnDecl->getLocation(),
diag::err_operator_new_delete_dependent_result_type)
<< FnDecl->getDeclName() << ExpectedResultType;
// Check that the result type is what we expect.
if (SemaRef.Context.getCanonicalType(ResultType) != ExpectedResultType)
return SemaRef.Diag(FnDecl->getLocation(),
diag::err_operator_new_delete_invalid_result_type)
<< FnDecl->getDeclName() << ExpectedResultType;
// A function template must have at least 2 parameters.
if (FnDecl->getDescribedFunctionTemplate() && FnDecl->getNumParams() < 2)
return SemaRef.Diag(FnDecl->getLocation(),
diag::err_operator_new_delete_template_too_few_parameters)
<< FnDecl->getDeclName();
// The function decl must have at least 1 parameter.
if (FnDecl->getNumParams() == 0)
return SemaRef.Diag(FnDecl->getLocation(),
diag::err_operator_new_delete_too_few_parameters)
<< FnDecl->getDeclName();
// Check the first parameter type is not dependent.
QualType FirstParamType = FnDecl->getParamDecl(0)->getType();
if (FirstParamType->isDependentType())
return SemaRef.Diag(FnDecl->getLocation(), DependentParamTypeDiag)
<< FnDecl->getDeclName() << ExpectedFirstParamType;
// Check that the first parameter type is what we expect.
if (SemaRef.Context.getCanonicalType(FirstParamType).getUnqualifiedType() !=
ExpectedFirstParamType)
return SemaRef.Diag(FnDecl->getLocation(), InvalidParamTypeDiag)
<< FnDecl->getDeclName() << ExpectedFirstParamType;
return false;
}
static bool
CheckOperatorNewDeclaration(Sema &SemaRef, const FunctionDecl *FnDecl) {
// C++ [basic.stc.dynamic.allocation]p1:
// A program is ill-formed if an allocation function is declared in a
// namespace scope other than global scope or declared static in global
// scope.
if (CheckOperatorNewDeleteDeclarationScope(SemaRef, FnDecl))
return true;
CanQualType SizeTy =
SemaRef.Context.getCanonicalType(SemaRef.Context.getSizeType());
// C++ [basic.stc.dynamic.allocation]p1:
// The return type shall be void*. The first parameter shall have type
// std::size_t.
if (CheckOperatorNewDeleteTypes(SemaRef, FnDecl, SemaRef.Context.VoidPtrTy,
SizeTy,
diag::err_operator_new_dependent_param_type,
diag::err_operator_new_param_type))
return true;
// C++ [basic.stc.dynamic.allocation]p1:
// The first parameter shall not have an associated default argument.
if (FnDecl->getParamDecl(0)->hasDefaultArg())
return SemaRef.Diag(FnDecl->getLocation(),
diag::err_operator_new_default_arg)
<< FnDecl->getDeclName() << FnDecl->getParamDecl(0)->getDefaultArgRange();
return false;
}
static bool
CheckOperatorDeleteDeclaration(Sema &SemaRef, FunctionDecl *FnDecl) {
// C++ [basic.stc.dynamic.deallocation]p1:
// A program is ill-formed if deallocation functions are declared in a
// namespace scope other than global scope or declared static in global
// scope.
if (CheckOperatorNewDeleteDeclarationScope(SemaRef, FnDecl))
return true;
// C++ [basic.stc.dynamic.deallocation]p2:
// Each deallocation function shall return void and its first parameter
// shall be void*.
if (CheckOperatorNewDeleteTypes(SemaRef, FnDecl, SemaRef.Context.VoidTy,
SemaRef.Context.VoidPtrTy,
diag::err_operator_delete_dependent_param_type,
diag::err_operator_delete_param_type))
return true;
return false;
}
/// CheckOverloadedOperatorDeclaration - Check whether the declaration
/// of this overloaded operator is well-formed. If so, returns false;
/// otherwise, emits appropriate diagnostics and returns true.
bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) {
assert(FnDecl && FnDecl->isOverloadedOperator() &&
"Expected an overloaded operator declaration");
OverloadedOperatorKind Op = FnDecl->getOverloadedOperator();
// C++ [over.oper]p5:
// The allocation and deallocation functions, operator new,
// operator new[], operator delete and operator delete[], are
// described completely in 3.7.3. The attributes and restrictions
// found in the rest of this subclause do not apply to them unless
// explicitly stated in 3.7.3.
if (Op == OO_Delete || Op == OO_Array_Delete)
return CheckOperatorDeleteDeclaration(*this, FnDecl);
if (Op == OO_New || Op == OO_Array_New)
return CheckOperatorNewDeclaration(*this, FnDecl);
// C++ [over.oper]p6:
// An operator function shall either be a non-static member
// function or be a non-member function and have at least one
// parameter whose type is a class, a reference to a class, an
// enumeration, or a reference to an enumeration.
if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) {
if (MethodDecl->isStatic())
return Diag(FnDecl->getLocation(),
diag::err_operator_overload_static) << FnDecl->getDeclName();
} else {
bool ClassOrEnumParam = false;
for (auto Param : FnDecl->params()) {
QualType ParamType = Param->getType().getNonReferenceType();
if (ParamType->isDependentType() || ParamType->isRecordType() ||
ParamType->isEnumeralType()) {
ClassOrEnumParam = true;
break;
}
}
if (!ClassOrEnumParam)
return Diag(FnDecl->getLocation(),
diag::err_operator_overload_needs_class_or_enum)
<< FnDecl->getDeclName();
}
// C++ [over.oper]p8:
// An operator function cannot have default arguments (8.3.6),
// except where explicitly stated below.
//
// Only the function-call operator allows default arguments
// (C++ [over.call]p1).
if (Op != OO_Call) {
for (auto Param : FnDecl->params()) {
if (Param->hasDefaultArg())
return Diag(Param->getLocation(),
diag::err_operator_overload_default_arg)
<< FnDecl->getDeclName() << Param->getDefaultArgRange();
}
}
static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = {
{ false, false, false }
#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \
, { Unary, Binary, MemberOnly }
#include "clang/Basic/OperatorKinds.def"
};
bool CanBeUnaryOperator = OperatorUses[Op][0];
bool CanBeBinaryOperator = OperatorUses[Op][1];
bool MustBeMemberOperator = OperatorUses[Op][2];
// C++ [over.oper]p8:
// [...] Operator functions cannot have more or fewer parameters
// than the number required for the corresponding operator, as
// described in the rest of this subclause.
unsigned NumParams = FnDecl->getNumParams()
+ (isa<CXXMethodDecl>(FnDecl)? 1 : 0);
if (Op != OO_Call &&
((NumParams == 1 && !CanBeUnaryOperator) ||
(NumParams == 2 && !CanBeBinaryOperator) ||
(NumParams < 1) || (NumParams > 2))) {
// We have the wrong number of parameters.
unsigned ErrorKind;
if (CanBeUnaryOperator && CanBeBinaryOperator) {
ErrorKind = 2; // 2 -> unary or binary.
} else if (CanBeUnaryOperator) {
ErrorKind = 0; // 0 -> unary
} else {
assert(CanBeBinaryOperator &&
"All non-call overloaded operators are unary or binary!");
ErrorKind = 1; // 1 -> binary
}
return Diag(FnDecl->getLocation(), diag::err_operator_overload_must_be)
<< FnDecl->getDeclName() << NumParams << ErrorKind;
}
// Overloaded operators other than operator() cannot be variadic.
if (Op != OO_Call &&
FnDecl->getType()->getAs<FunctionProtoType>()->isVariadic()) {
return Diag(FnDecl->getLocation(), diag::err_operator_overload_variadic)
<< FnDecl->getDeclName();
}
// Some operators must be non-static member functions.
if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) {
return Diag(FnDecl->getLocation(),
diag::err_operator_overload_must_be_member)
<< FnDecl->getDeclName();
}
// C++ [over.inc]p1:
// The user-defined function called operator++ implements the
// prefix and postfix ++ operator. If this function is a member
// function with no parameters, or a non-member function with one
// parameter of class or enumeration type, it defines the prefix
// increment operator ++ for objects of that type. If the function
// is a member function with one parameter (which shall be of type
// int) or a non-member function with two parameters (the second
// of which shall be of type int), it defines the postfix
// increment operator ++ for objects of that type.
if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) {
ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1);
QualType ParamType = LastParam->getType();
if (!ParamType->isSpecificBuiltinType(BuiltinType::Int) &&
!ParamType->isDependentType())
return Diag(LastParam->getLocation(),
diag::err_operator_overload_post_incdec_must_be_int)
<< LastParam->getType() << (Op == OO_MinusMinus);
}
return false;
}
/// CheckLiteralOperatorDeclaration - Check whether the declaration
/// of this literal operator function is well-formed. If so, returns
/// false; otherwise, emits appropriate diagnostics and returns true.
bool Sema::CheckLiteralOperatorDeclaration(FunctionDecl *FnDecl) {
if (isa<CXXMethodDecl>(FnDecl)) {
Diag(FnDecl->getLocation(), diag::err_literal_operator_outside_namespace)
<< FnDecl->getDeclName();
return true;
}
if (FnDecl->isExternC()) {
Diag(FnDecl->getLocation(), diag::err_literal_operator_extern_c);
return true;
}
bool Valid = false;
// This might be the definition of a literal operator template.
FunctionTemplateDecl *TpDecl = FnDecl->getDescribedFunctionTemplate();
// This might be a specialization of a literal operator template.
if (!TpDecl)
TpDecl = FnDecl->getPrimaryTemplate();
// template <char...> type operator "" name() and
// template <class T, T...> type operator "" name() are the only valid
// template signatures, and the only valid signatures with no parameters.
if (TpDecl) {
if (FnDecl->param_size() == 0) {
// Must have one or two template parameters
TemplateParameterList *Params = TpDecl->getTemplateParameters();
if (Params->size() == 1) {
NonTypeTemplateParmDecl *PmDecl =
dyn_cast<NonTypeTemplateParmDecl>(Params->getParam(0));
// The template parameter must be a char parameter pack.
if (PmDecl && PmDecl->isTemplateParameterPack() &&
Context.hasSameType(PmDecl->getType(), Context.CharTy))
Valid = true;
} else if (Params->size() == 2) {
TemplateTypeParmDecl *PmType =
dyn_cast<TemplateTypeParmDecl>(Params->getParam(0));
NonTypeTemplateParmDecl *PmArgs =
dyn_cast<NonTypeTemplateParmDecl>(Params->getParam(1));
// The second template parameter must be a parameter pack with the
// first template parameter as its type.
if (PmType && PmArgs &&
!PmType->isTemplateParameterPack() &&
PmArgs->isTemplateParameterPack()) {
const TemplateTypeParmType *TArgs =
PmArgs->getType()->getAs<TemplateTypeParmType>();
if (TArgs && TArgs->getDepth() == PmType->getDepth() &&
TArgs->getIndex() == PmType->getIndex()) {
Valid = true;
if (ActiveTemplateInstantiations.empty())
Diag(FnDecl->getLocation(),
diag::ext_string_literal_operator_template);
}
}
}
}
} else if (FnDecl->param_size()) {
// Check the first parameter
FunctionDecl::param_iterator Param = FnDecl->param_begin();
QualType T = (*Param)->getType().getUnqualifiedType();
// unsigned long long int, long double, and any character type are allowed
// as the only parameters.
if (Context.hasSameType(T, Context.UnsignedLongLongTy) ||
Context.hasSameType(T, Context.LongDoubleTy) ||
Context.hasSameType(T, Context.CharTy) ||
Context.hasSameType(T, Context.WideCharTy) ||
Context.hasSameType(T, Context.Char16Ty) ||
Context.hasSameType(T, Context.Char32Ty)) {
if (++Param == FnDecl->param_end())
Valid = true;
goto FinishedParams;
}
// Otherwise it must be a pointer to const; let's strip those qualifiers.
const PointerType *PT = T->getAs<PointerType>();
if (!PT)
goto FinishedParams;
T = PT->getPointeeType();
if (!T.isConstQualified() || T.isVolatileQualified())
goto FinishedParams;
T = T.getUnqualifiedType();
// Move on to the second parameter;
++Param;
// If there is no second parameter, the first must be a const char *
if (Param == FnDecl->param_end()) {
if (Context.hasSameType(T, Context.CharTy))
Valid = true;
goto FinishedParams;
}
// const char *, const wchar_t*, const char16_t*, and const char32_t*
// are allowed as the first parameter to a two-parameter function
if (!(Context.hasSameType(T, Context.CharTy) ||
Context.hasSameType(T, Context.WideCharTy) ||
Context.hasSameType(T, Context.Char16Ty) ||
Context.hasSameType(T, Context.Char32Ty)))
goto FinishedParams;
// The second and final parameter must be an std::size_t
T = (*Param)->getType().getUnqualifiedType();
if (Context.hasSameType(T, Context.getSizeType()) &&
++Param == FnDecl->param_end())
Valid = true;
}
// FIXME: This diagnostic is absolutely terrible.
FinishedParams:
if (!Valid) {
Diag(FnDecl->getLocation(), diag::err_literal_operator_params)
<< FnDecl->getDeclName();
return true;
}
// A parameter-declaration-clause containing a default argument is not
// equivalent to any of the permitted forms.
for (auto Param : FnDecl->params()) {
if (Param->hasDefaultArg()) {
Diag(Param->getDefaultArgRange().getBegin(),
diag::err_literal_operator_default_argument)
<< Param->getDefaultArgRange();
break;
}
}
StringRef LiteralName
= FnDecl->getDeclName().getCXXLiteralIdentifier()->getName();
if (LiteralName[0] != '_') {
// C++11 [usrlit.suffix]p1:
// Literal suffix identifiers that do not start with an underscore
// are reserved for future standardization.
Diag(FnDecl->getLocation(), diag::warn_user_literal_reserved)
<< NumericLiteralParser::isValidUDSuffix(getLangOpts(), LiteralName);
}
return false;
}
/// ActOnStartLinkageSpecification - Parsed the beginning of a C++
/// linkage specification, including the language and (if present)
/// the '{'. ExternLoc is the location of the 'extern', Lang is the
/// language string literal. LBraceLoc, if valid, provides the location of
/// the '{' brace. Otherwise, this linkage specification does not
/// have any braces.
Decl *Sema::ActOnStartLinkageSpecification(Scope *S, SourceLocation ExternLoc,
Expr *LangStr,
SourceLocation LBraceLoc) {
StringLiteral *Lit = cast<StringLiteral>(LangStr);
if (!Lit->isAscii()) {
Diag(LangStr->getExprLoc(), diag::err_language_linkage_spec_not_ascii)
<< LangStr->getSourceRange();
return nullptr;
}
StringRef Lang = Lit->getString();
LinkageSpecDecl::LanguageIDs Language;
if (Lang == "C")
Language = LinkageSpecDecl::lang_c;
else if (Lang == "C++")
Language = LinkageSpecDecl::lang_cxx;
else {
Diag(LangStr->getExprLoc(), diag::err_language_linkage_spec_unknown)
<< LangStr->getSourceRange();
return nullptr;
}
// FIXME: Add all the various semantics of linkage specifications
LinkageSpecDecl *D = LinkageSpecDecl::Create(Context, CurContext, ExternLoc,
LangStr->getExprLoc(), Language,
LBraceLoc.isValid());
CurContext->addDecl(D);
PushDeclContext(S, D);
return D;
}
/// ActOnFinishLinkageSpecification - Complete the definition of
/// the C++ linkage specification LinkageSpec. If RBraceLoc is
/// valid, it's the position of the closing '}' brace in a linkage
/// specification that uses braces.
Decl *Sema::ActOnFinishLinkageSpecification(Scope *S,
Decl *LinkageSpec,
SourceLocation RBraceLoc) {
if (RBraceLoc.isValid()) {
LinkageSpecDecl* LSDecl = cast<LinkageSpecDecl>(LinkageSpec);
LSDecl->setRBraceLoc(RBraceLoc);
}
PopDeclContext();
return LinkageSpec;
}
Decl *Sema::ActOnEmptyDeclaration(Scope *S,
AttributeList *AttrList,
SourceLocation SemiLoc) {
Decl *ED = EmptyDecl::Create(Context, CurContext, SemiLoc);
// Attribute declarations appertain to empty declaration so we handle
// them here.
if (AttrList)
ProcessDeclAttributeList(S, ED, AttrList);
CurContext->addDecl(ED);
return ED;
}
/// \brief Perform semantic analysis for the variable declaration that
/// occurs within a C++ catch clause, returning the newly-created
/// variable.
VarDecl *Sema::BuildExceptionDeclaration(Scope *S,
TypeSourceInfo *TInfo,
SourceLocation StartLoc,
SourceLocation Loc,
IdentifierInfo *Name) {
bool Invalid = false;
QualType ExDeclType = TInfo->getType();
// Arrays and functions decay.
if (ExDeclType->isArrayType())
ExDeclType = Context.getArrayDecayedType(ExDeclType);
else if (ExDeclType->isFunctionType())
ExDeclType = Context.getPointerType(ExDeclType);
// C++ 15.3p1: The exception-declaration shall not denote an incomplete type.
// The exception-declaration shall not denote a pointer or reference to an
// incomplete type, other than [cv] void*.
// N2844 forbids rvalue references.
if (!ExDeclType->isDependentType() && ExDeclType->isRValueReferenceType()) {
Diag(Loc, diag::err_catch_rvalue_ref);
Invalid = true;
}
QualType BaseType = ExDeclType;
int Mode = 0; // 0 for direct type, 1 for pointer, 2 for reference
unsigned DK = diag::err_catch_incomplete;
if (const PointerType *Ptr = BaseType->getAs<PointerType>()) {
BaseType = Ptr->getPointeeType();
Mode = 1;
DK = diag::err_catch_incomplete_ptr;
} else if (const ReferenceType *Ref = BaseType->getAs<ReferenceType>()) {
// For the purpose of error recovery, we treat rvalue refs like lvalue refs.
BaseType = Ref->getPointeeType();
Mode = 2;
DK = diag::err_catch_incomplete_ref;
}
if (!Invalid && (Mode == 0 || !BaseType->isVoidType()) &&
!BaseType->isDependentType() && RequireCompleteType(Loc, BaseType, DK))
Invalid = true;
if (!Invalid && !ExDeclType->isDependentType() &&
RequireNonAbstractType(Loc, ExDeclType,
diag::err_abstract_type_in_decl,
AbstractVariableType))
Invalid = true;
// Only the non-fragile NeXT runtime currently supports C++ catches
// of ObjC types, and no runtime supports catching ObjC types by value.
if (!Invalid && getLangOpts().ObjC1) {
QualType T = ExDeclType;
if (const ReferenceType *RT = T->getAs<ReferenceType>())
T = RT->getPointeeType();
if (T->isObjCObjectType()) {
Diag(Loc, diag::err_objc_object_catch);
Invalid = true;
} else if (T->isObjCObjectPointerType()) {
// FIXME: should this be a test for macosx-fragile specifically?
if (getLangOpts().ObjCRuntime.isFragile())
Diag(Loc, diag::warn_objc_pointer_cxx_catch_fragile);
}
}
VarDecl *ExDecl = VarDecl::Create(Context, CurContext, StartLoc, Loc, Name,
ExDeclType, TInfo, SC_None);
ExDecl->setExceptionVariable(true);
// In ARC, infer 'retaining' for variables of retainable type.
if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(ExDecl))
Invalid = true;
if (!Invalid && !ExDeclType->isDependentType()) {
if (const RecordType *recordType = ExDeclType->getAs<RecordType>()) {
// Insulate this from anything else we might currently be parsing.
EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
// C++ [except.handle]p16:
// The object declared in an exception-declaration or, if the
// exception-declaration does not specify a name, a temporary (12.2) is
// copy-initialized (8.5) from the exception object. [...]
// The object is destroyed when the handler exits, after the destruction
// of any automatic objects initialized within the handler.
//
// We just pretend to initialize the object with itself, then make sure
// it can be destroyed later.
QualType initType = ExDeclType;
InitializedEntity entity =
InitializedEntity::InitializeVariable(ExDecl);
InitializationKind initKind =
InitializationKind::CreateCopy(Loc, SourceLocation());
Expr *opaqueValue =
new (Context) OpaqueValueExpr(Loc, initType, VK_LValue, OK_Ordinary);
InitializationSequence sequence(*this, entity, initKind, opaqueValue);
ExprResult result = sequence.Perform(*this, entity, initKind, opaqueValue);
if (result.isInvalid())
Invalid = true;
else {
// If the constructor used was non-trivial, set this as the
// "initializer".
CXXConstructExpr *construct = result.getAs<CXXConstructExpr>();
if (!construct->getConstructor()->isTrivial()) {
Expr *init = MaybeCreateExprWithCleanups(construct);
ExDecl->setInit(init);
}
// And make sure it's destructable.
FinalizeVarWithDestructor(ExDecl, recordType);
}
}
}
if (Invalid)
ExDecl->setInvalidDecl();
return ExDecl;
}
/// ActOnExceptionDeclarator - Parsed the exception-declarator in a C++ catch
/// handler.
Decl *Sema::ActOnExceptionDeclarator(Scope *S, Declarator &D) {
TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
bool Invalid = D.isInvalidType();
// Check for unexpanded parameter packs.
if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
UPPC_ExceptionType)) {
TInfo = Context.getTrivialTypeSourceInfo(Context.IntTy,
D.getIdentifierLoc());
Invalid = true;
}
IdentifierInfo *II = D.getIdentifier();
if (NamedDecl *PrevDecl = LookupSingleName(S, II, D.getIdentifierLoc(),
LookupOrdinaryName,
ForRedeclaration)) {
// The scope should be freshly made just for us. There is just no way
// it contains any previous declaration, except for function parameters in
// a function-try-block's catch statement.
assert(!S->isDeclScope(PrevDecl));
if (isDeclInScope(PrevDecl, CurContext, S)) {
Diag(D.getIdentifierLoc(), diag::err_redefinition)
<< D.getIdentifier();
Diag(PrevDecl->getLocation(), diag::note_previous_definition);
Invalid = true;
} else if (PrevDecl->isTemplateParameter())
// Maybe we will complain about the shadowed template parameter.
DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
}
if (D.getCXXScopeSpec().isSet() && !Invalid) {
Diag(D.getIdentifierLoc(), diag::err_qualified_catch_declarator)
<< D.getCXXScopeSpec().getRange();
Invalid = true;
}
VarDecl *ExDecl = BuildExceptionDeclaration(S, TInfo,
D.getLocStart(),
D.getIdentifierLoc(),
D.getIdentifier());
if (Invalid)
ExDecl->setInvalidDecl();
// Add the exception declaration into this scope.
if (II)
PushOnScopeChains(ExDecl, S);
else
CurContext->addDecl(ExDecl);
ProcessDeclAttributes(S, ExDecl, D);
return ExDecl;
}
Decl *Sema::ActOnStaticAssertDeclaration(SourceLocation StaticAssertLoc,
Expr *AssertExpr,
Expr *AssertMessageExpr,
SourceLocation RParenLoc) {
StringLiteral *AssertMessage =
AssertMessageExpr ? cast<StringLiteral>(AssertMessageExpr) : nullptr;
if (DiagnoseUnexpandedParameterPack(AssertExpr, UPPC_StaticAssertExpression))
return nullptr;
return BuildStaticAssertDeclaration(StaticAssertLoc, AssertExpr,
AssertMessage, RParenLoc, false);
}
Decl *Sema::BuildStaticAssertDeclaration(SourceLocation StaticAssertLoc,
Expr *AssertExpr,
StringLiteral *AssertMessage,
SourceLocation RParenLoc,
bool Failed) {
assert(AssertExpr != nullptr && "Expected non-null condition");
if (!AssertExpr->isTypeDependent() && !AssertExpr->isValueDependent() &&
!Failed) {
// In a static_assert-declaration, the constant-expression shall be a
// constant expression that can be contextually converted to bool.
ExprResult Converted = PerformContextuallyConvertToBool(AssertExpr);
if (Converted.isInvalid())
Failed = true;
llvm::APSInt Cond;
if (!Failed && VerifyIntegerConstantExpression(Converted.get(), &Cond,
diag::err_static_assert_expression_is_not_constant,
/*AllowFold=*/false).isInvalid())
Failed = true;
if (!Failed && !Cond) {
SmallString<256> MsgBuffer;
llvm::raw_svector_ostream Msg(MsgBuffer);
if (AssertMessage)
AssertMessage->printPretty(Msg, nullptr, getPrintingPolicy());
Diag(StaticAssertLoc, diag::err_static_assert_failed)
<< !AssertMessage << Msg.str() << AssertExpr->getSourceRange();
Failed = true;
}
}
Decl *Decl = StaticAssertDecl::Create(Context, CurContext, StaticAssertLoc,
AssertExpr, AssertMessage, RParenLoc,
Failed);
CurContext->addDecl(Decl);
return Decl;
}
/// \brief Perform semantic analysis of the given friend type declaration.
///
/// \returns A friend declaration that.
FriendDecl *Sema::CheckFriendTypeDecl(SourceLocation LocStart,
SourceLocation FriendLoc,
TypeSourceInfo *TSInfo) {
assert(TSInfo && "NULL TypeSourceInfo for friend type declaration");
QualType T = TSInfo->getType();
SourceRange TypeRange = TSInfo->getTypeLoc().getLocalSourceRange();
// C++03 [class.friend]p2:
// An elaborated-type-specifier shall be used in a friend declaration
// for a class.*
//
// * The class-key of the elaborated-type-specifier is required.
if (!ActiveTemplateInstantiations.empty()) {
// Do not complain about the form of friend template types during
// template instantiation; we will already have complained when the
// template was declared.
} else {
if (!T->isElaboratedTypeSpecifier()) {
// If we evaluated the type to a record type, suggest putting
// a tag in front.
if (const RecordType *RT = T->getAs<RecordType>()) {
RecordDecl *RD = RT->getDecl();
SmallString<16> InsertionText(" ");
InsertionText += RD->getKindName();
Diag(TypeRange.getBegin(),
getLangOpts().CPlusPlus11 ?
diag::warn_cxx98_compat_unelaborated_friend_type :
diag::ext_unelaborated_friend_type)
<< (unsigned) RD->getTagKind()
<< T
<< FixItHint::CreateInsertion(PP.getLocForEndOfToken(FriendLoc),
InsertionText);
} else {
Diag(FriendLoc,
getLangOpts().CPlusPlus11 ?
diag::warn_cxx98_compat_nonclass_type_friend :
diag::ext_nonclass_type_friend)
<< T
<< TypeRange;
}
} else if (T->getAs<EnumType>()) {
Diag(FriendLoc,
getLangOpts().CPlusPlus11 ?
diag::warn_cxx98_compat_enum_friend :
diag::ext_enum_friend)
<< T
<< TypeRange;
}
// C++11 [class.friend]p3:
// A friend declaration that does not declare a function shall have one
// of the following forms:
// friend elaborated-type-specifier ;
// friend simple-type-specifier ;
// friend typename-specifier ;
if (getLangOpts().CPlusPlus11 && LocStart != FriendLoc)
Diag(FriendLoc, diag::err_friend_not_first_in_declaration) << T;
}
// If the type specifier in a friend declaration designates a (possibly
// cv-qualified) class type, that class is declared as a friend; otherwise,
// the friend declaration is ignored.
return FriendDecl::Create(Context, CurContext,
TSInfo->getTypeLoc().getLocStart(), TSInfo,
FriendLoc);
}
/// Handle a friend tag declaration where the scope specifier was
/// templated.
Decl *Sema::ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
unsigned TagSpec, SourceLocation TagLoc,
CXXScopeSpec &SS,
IdentifierInfo *Name,
SourceLocation NameLoc,
AttributeList *Attr,
MultiTemplateParamsArg TempParamLists) {
TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
bool isExplicitSpecialization = false;
bool Invalid = false;
if (TemplateParameterList *TemplateParams =
MatchTemplateParametersToScopeSpecifier(
TagLoc, NameLoc, SS, nullptr, TempParamLists, /*friend*/ true,
isExplicitSpecialization, Invalid)) {
if (TemplateParams->size() > 0) {
// This is a declaration of a class template.
if (Invalid)
return nullptr;
return CheckClassTemplate(S, TagSpec, TUK_Friend, TagLoc,
SS, Name, NameLoc, Attr,
TemplateParams, AS_public,
/*ModulePrivateLoc=*/SourceLocation(),
TempParamLists.size() - 1,
TempParamLists.data()).get();
} else {
// The "template<>" header is extraneous.
Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
<< TypeWithKeyword::getTagTypeKindName(Kind) << Name;
isExplicitSpecialization = true;
}
}
if (Invalid) return nullptr;
bool isAllExplicitSpecializations = true;
for (unsigned I = TempParamLists.size(); I-- > 0; ) {
if (TempParamLists[I]->size()) {
isAllExplicitSpecializations = false;
break;
}
}
// FIXME: don't ignore attributes.
// If it's explicit specializations all the way down, just forget
// about the template header and build an appropriate non-templated
// friend. TODO: for source fidelity, remember the headers.
if (isAllExplicitSpecializations) {
if (SS.isEmpty()) {
bool Owned = false;
bool IsDependent = false;
return ActOnTag(S, TagSpec, TUK_Friend, TagLoc, SS, Name, NameLoc,
Attr, AS_public,
/*ModulePrivateLoc=*/SourceLocation(),
MultiTemplateParamsArg(), Owned, IsDependent,
/*ScopedEnumKWLoc=*/SourceLocation(),
/*ScopedEnumUsesClassTag=*/false,
/*UnderlyingType=*/TypeResult(),
/*IsTypeSpecifier=*/false);
}
NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
ElaboratedTypeKeyword Keyword
= TypeWithKeyword::getKeywordForTagTypeKind(Kind);
QualType T = CheckTypenameType(Keyword, TagLoc, QualifierLoc,
*Name, NameLoc);
if (T.isNull())
return nullptr;
TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
if (isa<DependentNameType>(T)) {
DependentNameTypeLoc TL =
TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
TL.setElaboratedKeywordLoc(TagLoc);
TL.setQualifierLoc(QualifierLoc);
TL.setNameLoc(NameLoc);
} else {
ElaboratedTypeLoc TL = TSI->getTypeLoc().castAs<ElaboratedTypeLoc>();
TL.setElaboratedKeywordLoc(TagLoc);
TL.setQualifierLoc(QualifierLoc);
TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(NameLoc);
}
FriendDecl *Friend = FriendDecl::Create(Context, CurContext, NameLoc,
TSI, FriendLoc, TempParamLists);
Friend->setAccess(AS_public);
CurContext->addDecl(Friend);
return Friend;
}
assert(SS.isNotEmpty() && "valid templated tag with no SS and no direct?");
// Handle the case of a templated-scope friend class. e.g.
// template <class T> class A<T>::B;
// FIXME: we don't support these right now.
Diag(NameLoc, diag::warn_template_qualified_friend_unsupported)
<< SS.getScopeRep() << SS.getRange() << cast<CXXRecordDecl>(CurContext);
ElaboratedTypeKeyword ETK = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
QualType T = Context.getDependentNameType(ETK, SS.getScopeRep(), Name);
TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
DependentNameTypeLoc TL = TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
TL.setElaboratedKeywordLoc(TagLoc);
TL.setQualifierLoc(SS.getWithLocInContext(Context));
TL.setNameLoc(NameLoc);
FriendDecl *Friend = FriendDecl::Create(Context, CurContext, NameLoc,
TSI, FriendLoc, TempParamLists);
Friend->setAccess(AS_public);
Friend->setUnsupportedFriend(true);
CurContext->addDecl(Friend);
return Friend;
}
/// Handle a friend type declaration. This works in tandem with
/// ActOnTag.
///
/// Notes on friend class templates:
///
/// We generally treat friend class declarations as if they were
/// declaring a class. So, for example, the elaborated type specifier
/// in a friend declaration is required to obey the restrictions of a
/// class-head (i.e. no typedefs in the scope chain), template
/// parameters are required to match up with simple template-ids, &c.
/// However, unlike when declaring a template specialization, it's
/// okay to refer to a template specialization without an empty
/// template parameter declaration, e.g.
/// friend class A<T>::B<unsigned>;
/// We permit this as a special case; if there are any template
/// parameters present at all, require proper matching, i.e.
/// template <> template \<class T> friend class A<int>::B;
Decl *Sema::ActOnFriendTypeDecl(Scope *S, const DeclSpec &DS,
MultiTemplateParamsArg TempParams) {
SourceLocation Loc = DS.getLocStart();
assert(DS.isFriendSpecified());
assert(DS.getStorageClassSpec() == DeclSpec::SCS_unspecified);
// Try to convert the decl specifier to a type. This works for
// friend templates because ActOnTag never produces a ClassTemplateDecl
// for a TUK_Friend.
Declarator TheDeclarator(DS, Declarator::MemberContext);
TypeSourceInfo *TSI = GetTypeForDeclarator(TheDeclarator, S);
QualType T = TSI->getType();
if (TheDeclarator.isInvalidType())
return nullptr;
if (DiagnoseUnexpandedParameterPack(Loc, TSI, UPPC_FriendDeclaration))
return nullptr;
// This is definitely an error in C++98. It's probably meant to
// be forbidden in C++0x, too, but the specification is just
// poorly written.
//
// The problem is with declarations like the following:
// template <T> friend A<T>::foo;
// where deciding whether a class C is a friend or not now hinges
// on whether there exists an instantiation of A that causes
// 'foo' to equal C. There are restrictions on class-heads
// (which we declare (by fiat) elaborated friend declarations to
// be) that makes this tractable.
//
// FIXME: handle "template <> friend class A<T>;", which
// is possibly well-formed? Who even knows?
if (TempParams.size() && !T->isElaboratedTypeSpecifier()) {
Diag(Loc, diag::err_tagless_friend_type_template)
<< DS.getSourceRange();
return nullptr;
}
// C++98 [class.friend]p1: A friend of a class is a function
// or class that is not a member of the class . . .
// This is fixed in DR77, which just barely didn't make the C++03
// deadline. It's also a very silly restriction that seriously
// affects inner classes and which nobody else seems to implement;
// thus we never diagnose it, not even in -pedantic.
//
// But note that we could warn about it: it's always useless to
// friend one of your own members (it's not, however, worthless to
// friend a member of an arbitrary specialization of your template).
Decl *D;
if (unsigned NumTempParamLists = TempParams.size())
D = FriendTemplateDecl::Create(Context, CurContext, Loc,
NumTempParamLists,
TempParams.data(),
TSI,
DS.getFriendSpecLoc());
else
D = CheckFriendTypeDecl(Loc, DS.getFriendSpecLoc(), TSI);
if (!D)
return nullptr;
D->setAccess(AS_public);
CurContext->addDecl(D);
return D;
}
NamedDecl *Sema::ActOnFriendFunctionDecl(Scope *S, Declarator &D,
MultiTemplateParamsArg TemplateParams) {
const DeclSpec &DS = D.getDeclSpec();
assert(DS.isFriendSpecified());
assert(DS.getStorageClassSpec() == DeclSpec::SCS_unspecified);
SourceLocation Loc = D.getIdentifierLoc();
TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
// C++ [class.friend]p1
// A friend of a class is a function or class....
// Note that this sees through typedefs, which is intended.
// It *doesn't* see through dependent types, which is correct
// according to [temp.arg.type]p3:
// If a declaration acquires a function type through a
// type dependent on a template-parameter and this causes
// a declaration that does not use the syntactic form of a
// function declarator to have a function type, the program
// is ill-formed.
if (!TInfo->getType()->isFunctionType()) {
Diag(Loc, diag::err_unexpected_friend);
// It might be worthwhile to try to recover by creating an
// appropriate declaration.
return nullptr;
}
// C++ [namespace.memdef]p3
// - If a friend declaration in a non-local class first declares a
// class or function, the friend class or function is a member
// of the innermost enclosing namespace.
// - The name of the friend is not found by simple name lookup
// until a matching declaration is provided in that namespace
// scope (either before or after the class declaration granting
// friendship).
// - If a friend function is called, its name may be found by the
// name lookup that considers functions from namespaces and
// classes associated with the types of the function arguments.
// - When looking for a prior declaration of a class or a function
// declared as a friend, scopes outside the innermost enclosing
// namespace scope are not considered.
CXXScopeSpec &SS = D.getCXXScopeSpec();
DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
DeclarationName Name = NameInfo.getName();
assert(Name);
// Check for unexpanded parameter packs.
if (DiagnoseUnexpandedParameterPack(Loc, TInfo, UPPC_FriendDeclaration) ||
DiagnoseUnexpandedParameterPack(NameInfo, UPPC_FriendDeclaration) ||
DiagnoseUnexpandedParameterPack(SS, UPPC_FriendDeclaration))
return nullptr;
// The context we found the declaration in, or in which we should
// create the declaration.
DeclContext *DC;
Scope *DCScope = S;
LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
ForRedeclaration);
// There are five cases here.
// - There's no scope specifier and we're in a local class. Only look
// for functions declared in the immediately-enclosing block scope.
// We recover from invalid scope qualifiers as if they just weren't there.
FunctionDecl *FunctionContainingLocalClass = nullptr;
if ((SS.isInvalid() || !SS.isSet()) &&
(FunctionContainingLocalClass =
cast<CXXRecordDecl>(CurContext)->isLocalClass())) {
// C++11 [class.friend]p11:
// If a friend declaration appears in a local class and the name
// specified is an unqualified name, a prior declaration is
// looked up without considering scopes that are outside the
// innermost enclosing non-class scope. For a friend function
// declaration, if there is no prior declaration, the program is
// ill-formed.
// Find the innermost enclosing non-class scope. This is the block
// scope containing the local class definition (or for a nested class,
// the outer local class).
DCScope = S->getFnParent();
// Look up the function name in the scope.
Previous.clear(LookupLocalFriendName);
LookupName(Previous, S, /*AllowBuiltinCreation*/false);
if (!Previous.empty()) {
// All possible previous declarations must have the same context:
// either they were declared at block scope or they are members of
// one of the enclosing local classes.
DC = Previous.getRepresentativeDecl()->getDeclContext();
} else {
// This is ill-formed, but provide the context that we would have
// declared the function in, if we were permitted to, for error recovery.
DC = FunctionContainingLocalClass;
}
adjustContextForLocalExternDecl(DC);
// C++ [class.friend]p6:
// A function can be defined in a friend declaration of a class if and
// only if the class is a non-local class (9.8), the function name is
// unqualified, and the function has namespace scope.
if (D.isFunctionDefinition()) {
Diag(NameInfo.getBeginLoc(), diag::err_friend_def_in_local_class);
}
// - There's no scope specifier, in which case we just go to the
// appropriate scope and look for a function or function template
// there as appropriate.
} else if (SS.isInvalid() || !SS.isSet()) {
// C++11 [namespace.memdef]p3:
// If the name in a friend declaration is neither qualified nor
// a template-id and the declaration is a function or an
// elaborated-type-specifier, the lookup to determine whether
// the entity has been previously declared shall not consider
// any scopes outside the innermost enclosing namespace.
bool isTemplateId = D.getName().getKind() == UnqualifiedId::IK_TemplateId;
// Find the appropriate context according to the above.
DC = CurContext;
// Skip class contexts. If someone can cite chapter and verse
// for this behavior, that would be nice --- it's what GCC and
// EDG do, and it seems like a reasonable intent, but the spec
// really only says that checks for unqualified existing
// declarations should stop at the nearest enclosing namespace,
// not that they should only consider the nearest enclosing
// namespace.
while (DC->isRecord())
DC = DC->getParent();
DeclContext *LookupDC = DC;
while (LookupDC->isTransparentContext())
LookupDC = LookupDC->getParent();
while (true) {
LookupQualifiedName(Previous, LookupDC);
if (!Previous.empty()) {
DC = LookupDC;
break;
}
if (isTemplateId) {
if (isa<TranslationUnitDecl>(LookupDC)) break;
} else {
if (LookupDC->isFileContext()) break;
}
LookupDC = LookupDC->getParent();
}
DCScope = getScopeForDeclContext(S, DC);
// - There's a non-dependent scope specifier, in which case we
// compute it and do a previous lookup there for a function
// or function template.
} else if (!SS.getScopeRep()->isDependent()) {
DC = computeDeclContext(SS);
if (!DC) return nullptr;
if (RequireCompleteDeclContext(SS, DC)) return nullptr;
LookupQualifiedName(Previous, DC);
// Ignore things found implicitly in the wrong scope.
// TODO: better diagnostics for this case. Suggesting the right
// qualified scope would be nice...
LookupResult::Filter F = Previous.makeFilter();
while (F.hasNext()) {
NamedDecl *D = F.next();
if (!DC->InEnclosingNamespaceSetOf(
D->getDeclContext()->getRedeclContext()))
F.erase();
}
F.done();
if (Previous.empty()) {
D.setInvalidType();
Diag(Loc, diag::err_qualified_friend_not_found)
<< Name << TInfo->getType();
return nullptr;
}
// C++ [class.friend]p1: A friend of a class is a function or
// class that is not a member of the class . . .
if (DC->Equals(CurContext))
Diag(DS.getFriendSpecLoc(),
getLangOpts().CPlusPlus11 ?
diag::warn_cxx98_compat_friend_is_member :
diag::err_friend_is_member);
if (D.isFunctionDefinition()) {
// C++ [class.friend]p6:
// A function can be defined in a friend declaration of a class if and
// only if the class is a non-local class (9.8), the function name is
// unqualified, and the function has namespace scope.
SemaDiagnosticBuilder DB
= Diag(SS.getRange().getBegin(), diag::err_qualified_friend_def);
DB << SS.getScopeRep();
if (DC->isFileContext())
DB << FixItHint::CreateRemoval(SS.getRange());
SS.clear();
}
// - There's a scope specifier that does not match any template
// parameter lists, in which case we use some arbitrary context,
// create a method or method template, and wait for instantiation.
// - There's a scope specifier that does match some template
// parameter lists, which we don't handle right now.
} else {
if (D.isFunctionDefinition()) {
// C++ [class.friend]p6:
// A function can be defined in a friend declaration of a class if and
// only if the class is a non-local class (9.8), the function name is
// unqualified, and the function has namespace scope.
Diag(SS.getRange().getBegin(), diag::err_qualified_friend_def)
<< SS.getScopeRep();
}
DC = CurContext;
assert(isa<CXXRecordDecl>(DC) && "friend declaration not in class?");
}
if (!DC->isRecord()) {
// This implies that it has to be an operator or function.
if (D.getName().getKind() == UnqualifiedId::IK_ConstructorName ||
D.getName().getKind() == UnqualifiedId::IK_DestructorName ||
D.getName().getKind() == UnqualifiedId::IK_ConversionFunctionId) {
Diag(Loc, diag::err_introducing_special_friend) <<
(D.getName().getKind() == UnqualifiedId::IK_ConstructorName ? 0 :
D.getName().getKind() == UnqualifiedId::IK_DestructorName ? 1 : 2);
return nullptr;
}
}
// FIXME: This is an egregious hack to cope with cases where the scope stack
// does not contain the declaration context, i.e., in an out-of-line
// definition of a class.
Scope FakeDCScope(S, Scope::DeclScope, Diags);
if (!DCScope) {
FakeDCScope.setEntity(DC);
DCScope = &FakeDCScope;
}
bool AddToScope = true;
NamedDecl *ND = ActOnFunctionDeclarator(DCScope, D, DC, TInfo, Previous,
TemplateParams, AddToScope);
if (!ND) return nullptr;
assert(ND->getLexicalDeclContext() == CurContext);
// If we performed typo correction, we might have added a scope specifier
// and changed the decl context.
DC = ND->getDeclContext();
// Add the function declaration to the appropriate lookup tables,
// adjusting the redeclarations list as necessary. We don't
// want to do this yet if the friending class is dependent.
//
// Also update the scope-based lookup if the target context's
// lookup context is in lexical scope.
if (!CurContext->isDependentContext()) {
DC = DC->getRedeclContext();
DC->makeDeclVisibleInContext(ND);
if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
PushOnScopeChains(ND, EnclosingScope, /*AddToContext=*/ false);
}
FriendDecl *FrD = FriendDecl::Create(Context, CurContext,
D.getIdentifierLoc(), ND,
DS.getFriendSpecLoc());
FrD->setAccess(AS_public);
CurContext->addDecl(FrD);
if (ND->isInvalidDecl()) {
FrD->setInvalidDecl();
} else {
if (DC->isRecord()) CheckFriendAccess(ND);
FunctionDecl *FD;
if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
FD = FTD->getTemplatedDecl();
else
FD = cast<FunctionDecl>(ND);
// C++11 [dcl.fct.default]p4: If a friend declaration specifies a
// default argument expression, that declaration shall be a definition
// and shall be the only declaration of the function or function
// template in the translation unit.
if (functionDeclHasDefaultArgument(FD)) {
if (FunctionDecl *OldFD = FD->getPreviousDecl()) {
Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
Diag(OldFD->getLocation(), diag::note_previous_declaration);
} else if (!D.isFunctionDefinition())
Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_must_be_def);
}
// Mark templated-scope function declarations as unsupported.
if (FD->getNumTemplateParameterLists())
FrD->setUnsupportedFriend(true);
}
return ND;
}
void Sema::SetDeclDeleted(Decl *Dcl, SourceLocation DelLoc) {
AdjustDeclIfTemplate(Dcl);
FunctionDecl *Fn = dyn_cast_or_null<FunctionDecl>(Dcl);
if (!Fn) {
Diag(DelLoc, diag::err_deleted_non_function);
return;
}
if (const FunctionDecl *Prev = Fn->getPreviousDecl()) {
// Don't consider the implicit declaration we generate for explicit
// specializations. FIXME: Do not generate these implicit declarations.
if ((Prev->getTemplateSpecializationKind() != TSK_ExplicitSpecialization ||
Prev->getPreviousDecl()) &&
!Prev->isDefined()) {
Diag(DelLoc, diag::err_deleted_decl_not_first);
Diag(Prev->getLocation().isInvalid() ? DelLoc : Prev->getLocation(),
Prev->isImplicit() ? diag::note_previous_implicit_declaration
: diag::note_previous_declaration);
}
// If the declaration wasn't the first, we delete the function anyway for
// recovery.
Fn = Fn->getCanonicalDecl();
}
// dllimport/dllexport cannot be deleted.
if (const InheritableAttr *DLLAttr = getDLLAttr(Fn)) {
Diag(Fn->getLocation(), diag::err_attribute_dll_deleted) << DLLAttr;
Fn->setInvalidDecl();
}
if (Fn->isDeleted())
return;
// See if we're deleting a function which is already known to override a
// non-deleted virtual function.
if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Fn)) {
bool IssuedDiagnostic = false;
for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
E = MD->end_overridden_methods();
I != E; ++I) {
if (!(*MD->begin_overridden_methods())->isDeleted()) {
if (!IssuedDiagnostic) {
Diag(DelLoc, diag::err_deleted_override) << MD->getDeclName();
IssuedDiagnostic = true;
}
Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
}
}
}
// C++11 [basic.start.main]p3:
// A program that defines main as deleted [...] is ill-formed.
if (Fn->isMain())
Diag(DelLoc, diag::err_deleted_main);
Fn->setDeletedAsWritten();
}
void Sema::SetDeclDefaulted(Decl *Dcl, SourceLocation DefaultLoc) {
CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Dcl);
if (MD) {
if (MD->getParent()->isDependentType()) {
MD->setDefaulted();
MD->setExplicitlyDefaulted();
return;
}
CXXSpecialMember Member = getSpecialMember(MD);
if (Member == CXXInvalid) {
if (!MD->isInvalidDecl())
Diag(DefaultLoc, diag::err_default_special_members);
return;
}
MD->setDefaulted();
MD->setExplicitlyDefaulted();
// If this definition appears within the record, do the checking when
// the record is complete.
const FunctionDecl *Primary = MD;
if (const FunctionDecl *Pattern = MD->getTemplateInstantiationPattern())
// Find the uninstantiated declaration that actually had the '= default'
// on it.
Pattern->isDefined(Primary);
// If the method was defaulted on its first declaration, we will have
// already performed the checking in CheckCompletedCXXClass. Such a
// declaration doesn't trigger an implicit definition.
if (Primary == Primary->getCanonicalDecl())
return;
CheckExplicitlyDefaultedSpecialMember(MD);
// The exception specification is needed because we are defining the
// function.
ResolveExceptionSpec(DefaultLoc,
MD->getType()->castAs<FunctionProtoType>());
if (MD->isInvalidDecl())
return;
switch (Member) {
case CXXDefaultConstructor:
DefineImplicitDefaultConstructor(DefaultLoc,
cast<CXXConstructorDecl>(MD));
break;
case CXXCopyConstructor:
DefineImplicitCopyConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
break;
case CXXCopyAssignment:
DefineImplicitCopyAssignment(DefaultLoc, MD);
break;
case CXXDestructor:
DefineImplicitDestructor(DefaultLoc, cast<CXXDestructorDecl>(MD));
break;
case CXXMoveConstructor:
DefineImplicitMoveConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
break;
case CXXMoveAssignment:
DefineImplicitMoveAssignment(DefaultLoc, MD);
break;
case CXXInvalid:
llvm_unreachable("Invalid special member.");
}
} else {
Diag(DefaultLoc, diag::err_default_special_members);
}
}
static void SearchForReturnInStmt(Sema &Self, Stmt *S) {
for (Stmt::child_range CI = S->children(); CI; ++CI) {
Stmt *SubStmt = *CI;
if (!SubStmt)
continue;
if (isa<ReturnStmt>(SubStmt))
Self.Diag(SubStmt->getLocStart(),
diag::err_return_in_constructor_handler);
if (!isa<Expr>(SubStmt))
SearchForReturnInStmt(Self, SubStmt);
}
}
void Sema::DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock) {
for (unsigned I = 0, E = TryBlock->getNumHandlers(); I != E; ++I) {
CXXCatchStmt *Handler = TryBlock->getHandler(I);
SearchForReturnInStmt(*this, Handler);
}
}
bool Sema::CheckOverridingFunctionAttributes(const CXXMethodDecl *New,
const CXXMethodDecl *Old) {
const FunctionType *NewFT = New->getType()->getAs<FunctionType>();
const FunctionType *OldFT = Old->getType()->getAs<FunctionType>();
CallingConv NewCC = NewFT->getCallConv(), OldCC = OldFT->getCallConv();
// If the calling conventions match, everything is fine
if (NewCC == OldCC)
return false;
// If the calling conventions mismatch because the new function is static,
// suppress the calling convention mismatch error; the error about static
// function override (err_static_overrides_virtual from
// Sema::CheckFunctionDeclaration) is more clear.
if (New->getStorageClass() == SC_Static)
return false;
Diag(New->getLocation(),
diag::err_conflicting_overriding_cc_attributes)
<< New->getDeclName() << New->getType() << Old->getType();
Diag(Old->getLocation(), diag::note_overridden_virtual_function);
return true;
}
bool Sema::CheckOverridingFunctionReturnType(const CXXMethodDecl *New,
const CXXMethodDecl *Old) {
QualType NewTy = New->getType()->getAs<FunctionType>()->getReturnType();
QualType OldTy = Old->getType()->getAs<FunctionType>()->getReturnType();
if (Context.hasSameType(NewTy, OldTy) ||
NewTy->isDependentType() || OldTy->isDependentType())
return false;
// Check if the return types are covariant
QualType NewClassTy, OldClassTy;
/// Both types must be pointers or references to classes.
if (const PointerType *NewPT = NewTy->getAs<PointerType>()) {
if (const PointerType *OldPT = OldTy->getAs<PointerType>()) {
NewClassTy = NewPT->getPointeeType();
OldClassTy = OldPT->getPointeeType();
}
} else if (const ReferenceType *NewRT = NewTy->getAs<ReferenceType>()) {
if (const ReferenceType *OldRT = OldTy->getAs<ReferenceType>()) {
if (NewRT->getTypeClass() == OldRT->getTypeClass()) {
NewClassTy = NewRT->getPointeeType();
OldClassTy = OldRT->getPointeeType();
}
}
}
// The return types aren't either both pointers or references to a class type.
if (NewClassTy.isNull()) {
Diag(New->getLocation(),
diag::err_different_return_type_for_overriding_virtual_function)
<< New->getDeclName() << NewTy << OldTy
<< New->getReturnTypeSourceRange();
Diag(Old->getLocation(), diag::note_overridden_virtual_function)
<< Old->getReturnTypeSourceRange();
return true;
}
// C++ [class.virtual]p6:
// If the return type of D::f differs from the return type of B::f, the
// class type in the return type of D::f shall be complete at the point of
// declaration of D::f or shall be the class type D.
if (const RecordType *RT = NewClassTy->getAs<RecordType>()) {
if (!RT->isBeingDefined() &&
RequireCompleteType(New->getLocation(), NewClassTy,
diag::err_covariant_return_incomplete,
New->getDeclName()))
return true;
}
if (!Context.hasSameUnqualifiedType(NewClassTy, OldClassTy)) {
// Check if the new class derives from the old class.
if (!IsDerivedFrom(NewClassTy, OldClassTy)) {
Diag(New->getLocation(), diag::err_covariant_return_not_derived)
<< New->getDeclName() << NewTy << OldTy
<< New->getReturnTypeSourceRange();
Diag(Old->getLocation(), diag::note_overridden_virtual_function)
<< Old->getReturnTypeSourceRange();
return true;
}
// Check if we the conversion from derived to base is valid.
if (CheckDerivedToBaseConversion(
NewClassTy, OldClassTy,
diag::err_covariant_return_inaccessible_base,
diag::err_covariant_return_ambiguous_derived_to_base_conv,
New->getLocation(), New->getReturnTypeSourceRange(),
New->getDeclName(), nullptr)) {
// FIXME: this note won't trigger for delayed access control
// diagnostics, and it's impossible to get an undelayed error
// here from access control during the original parse because
// the ParsingDeclSpec/ParsingDeclarator are still in scope.
Diag(Old->getLocation(), diag::note_overridden_virtual_function)
<< Old->getReturnTypeSourceRange();
return true;
}
}
// The qualifiers of the return types must be the same.
if (NewTy.getLocalCVRQualifiers() != OldTy.getLocalCVRQualifiers()) {
Diag(New->getLocation(),
diag::err_covariant_return_type_different_qualifications)
<< New->getDeclName() << NewTy << OldTy
<< New->getReturnTypeSourceRange();
Diag(Old->getLocation(), diag::note_overridden_virtual_function)
<< Old->getReturnTypeSourceRange();
return true;
};
// The new class type must have the same or less qualifiers as the old type.
if (NewClassTy.isMoreQualifiedThan(OldClassTy)) {
Diag(New->getLocation(),
diag::err_covariant_return_type_class_type_more_qualified)
<< New->getDeclName() << NewTy << OldTy
<< New->getReturnTypeSourceRange();
Diag(Old->getLocation(), diag::note_overridden_virtual_function)
<< Old->getReturnTypeSourceRange();
return true;
};
return false;
}
/// \brief Mark the given method pure.
///
/// \param Method the method to be marked pure.
///
/// \param InitRange the source range that covers the "0" initializer.
bool Sema::CheckPureMethod(CXXMethodDecl *Method, SourceRange InitRange) {
SourceLocation EndLoc = InitRange.getEnd();
if (EndLoc.isValid())
Method->setRangeEnd(EndLoc);
if (Method->isVirtual() || Method->getParent()->isDependentContext()) {
Method->setPure();
return false;
}
if (!Method->isInvalidDecl())
Diag(Method->getLocation(), diag::err_non_virtual_pure)
<< Method->getDeclName() << InitRange;
return true;
}
/// \brief Determine whether the given declaration is a static data member.
static bool isStaticDataMember(const Decl *D) {
if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(D))
return Var->isStaticDataMember();
return false;
}
/// ActOnCXXEnterDeclInitializer - Invoked when we are about to parse
/// an initializer for the out-of-line declaration 'Dcl'. The scope
/// is a fresh scope pushed for just this purpose.
///
/// After this method is called, according to [C++ 3.4.1p13], if 'Dcl' is a
/// static data member of class X, names should be looked up in the scope of
/// class X.
void Sema::ActOnCXXEnterDeclInitializer(Scope *S, Decl *D) {
// If there is no declaration, there was an error parsing it.
if (!D || D->isInvalidDecl())
return;
// We will always have a nested name specifier here, but this declaration
// might not be out of line if the specifier names the current namespace:
// extern int n;
// int ::n = 0;
if (D->isOutOfLine())
EnterDeclaratorContext(S, D->getDeclContext());
// If we are parsing the initializer for a static data member, push a
// new expression evaluation context that is associated with this static
// data member.
if (isStaticDataMember(D))
PushExpressionEvaluationContext(PotentiallyEvaluated, D);
}
/// ActOnCXXExitDeclInitializer - Invoked after we are finished parsing an
/// initializer for the out-of-line declaration 'D'.
void Sema::ActOnCXXExitDeclInitializer(Scope *S, Decl *D) {
// If there is no declaration, there was an error parsing it.
if (!D || D->isInvalidDecl())
return;
if (isStaticDataMember(D))
PopExpressionEvaluationContext();
if (D->isOutOfLine())
ExitDeclaratorContext(S);
}
/// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
/// C++ if/switch/while/for statement.
/// e.g: "if (int x = f()) {...}"
DeclResult Sema::ActOnCXXConditionDeclaration(Scope *S, Declarator &D) {
// C++ 6.4p2:
// The declarator shall not specify a function or an array.
// The type-specifier-seq shall not contain typedef and shall not declare a
// new class or enumeration.
assert(D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
"Parser allowed 'typedef' as storage class of condition decl.");
Decl *Dcl = ActOnDeclarator(S, D);
if (!Dcl)
return true;
if (isa<FunctionDecl>(Dcl)) { // The declarator shall not specify a function.
Diag(Dcl->getLocation(), diag::err_invalid_use_of_function_type)
<< D.getSourceRange();
return true;
}
return Dcl;
}
void Sema::LoadExternalVTableUses() {
if (!ExternalSource)
return;
SmallVector<ExternalVTableUse, 4> VTables;
ExternalSource->ReadUsedVTables(VTables);
SmallVector<VTableUse, 4> NewUses;
for (unsigned I = 0, N = VTables.size(); I != N; ++I) {
llvm::DenseMap<CXXRecordDecl *, bool>::iterator Pos
= VTablesUsed.find(VTables[I].Record);
// Even if a definition wasn't required before, it may be required now.
if (Pos != VTablesUsed.end()) {
if (!Pos->second && VTables[I].DefinitionRequired)
Pos->second = true;
continue;
}
VTablesUsed[VTables[I].Record] = VTables[I].DefinitionRequired;
NewUses.push_back(VTableUse(VTables[I].Record, VTables[I].Location));
}
VTableUses.insert(VTableUses.begin(), NewUses.begin(), NewUses.end());
}
void Sema::MarkVTableUsed(SourceLocation Loc, CXXRecordDecl *Class,
bool DefinitionRequired) {
// Ignore any vtable uses in unevaluated operands or for classes that do
// not have a vtable.
if (!Class->isDynamicClass() || Class->isDependentContext() ||
CurContext->isDependentContext() || isUnevaluatedContext())
return;
// Try to insert this class into the map.
LoadExternalVTableUses();
Class = cast<CXXRecordDecl>(Class->getCanonicalDecl());
std::pair<llvm::DenseMap<CXXRecordDecl *, bool>::iterator, bool>
Pos = VTablesUsed.insert(std::make_pair(Class, DefinitionRequired));
if (!Pos.second) {
// If we already had an entry, check to see if we are promoting this vtable
// to required a definition. If so, we need to reappend to the VTableUses
// list, since we may have already processed the first entry.
if (DefinitionRequired && !Pos.first->second) {
Pos.first->second = true;
} else {
// Otherwise, we can early exit.
return;
}
} else {
// The Microsoft ABI requires that we perform the destructor body
// checks (i.e. operator delete() lookup) when the vtable is marked used, as
// the deleting destructor is emitted with the vtable, not with the
// destructor definition as in the Itanium ABI.
// If it has a definition, we do the check at that point instead.
if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
Class->hasUserDeclaredDestructor() &&
!Class->getDestructor()->isDefined() &&
!Class->getDestructor()->isDeleted()) {
CXXDestructorDecl *DD = Class->getDestructor();
ContextRAII SavedContext(*this, DD);
CheckDestructor(DD);
}
}
// Local classes need to have their virtual members marked
// immediately. For all other classes, we mark their virtual members
// at the end of the translation unit.
if (Class->isLocalClass())
MarkVirtualMembersReferenced(Loc, Class);
else
VTableUses.push_back(std::make_pair(Class, Loc));
}
bool Sema::DefineUsedVTables() {
LoadExternalVTableUses();
if (VTableUses.empty())
return false;
// Note: The VTableUses vector could grow as a result of marking
// the members of a class as "used", so we check the size each
// time through the loop and prefer indices (which are stable) to
// iterators (which are not).
bool DefinedAnything = false;
for (unsigned I = 0; I != VTableUses.size(); ++I) {
CXXRecordDecl *Class = VTableUses[I].first->getDefinition();
if (!Class)
continue;
SourceLocation Loc = VTableUses[I].second;
bool DefineVTable = true;
// If this class has a key function, but that key function is
// defined in another translation unit, we don't need to emit the
// vtable even though we're using it.
const CXXMethodDecl *KeyFunction = Context.getCurrentKeyFunction(Class);
if (KeyFunction && !KeyFunction->hasBody()) {
// The key function is in another translation unit.
DefineVTable = false;
TemplateSpecializationKind TSK =
KeyFunction->getTemplateSpecializationKind();
assert(TSK != TSK_ExplicitInstantiationDefinition &&
TSK != TSK_ImplicitInstantiation &&
"Instantiations don't have key functions");
(void)TSK;
} else if (!KeyFunction) {
// If we have a class with no key function that is the subject
// of an explicit instantiation declaration, suppress the
// vtable; it will live with the explicit instantiation
// definition.
bool IsExplicitInstantiationDeclaration
= Class->getTemplateSpecializationKind()
== TSK_ExplicitInstantiationDeclaration;
for (auto R : Class->redecls()) {
TemplateSpecializationKind TSK
= cast<CXXRecordDecl>(R)->getTemplateSpecializationKind();
if (TSK == TSK_ExplicitInstantiationDeclaration)
IsExplicitInstantiationDeclaration = true;
else if (TSK == TSK_ExplicitInstantiationDefinition) {
IsExplicitInstantiationDeclaration = false;
break;
}
}
if (IsExplicitInstantiationDeclaration)
DefineVTable = false;
}
// The exception specifications for all virtual members may be needed even
// if we are not providing an authoritative form of the vtable in this TU.
// We may choose to emit it available_externally anyway.
if (!DefineVTable) {
MarkVirtualMemberExceptionSpecsNeeded(Loc, Class);
continue;
}
// Mark all of the virtual members of this class as referenced, so
// that we can build a vtable. Then, tell the AST consumer that a
// vtable for this class is required.
DefinedAnything = true;
MarkVirtualMembersReferenced(Loc, Class);
CXXRecordDecl *Canonical = cast<CXXRecordDecl>(Class->getCanonicalDecl());
Consumer.HandleVTable(Class, VTablesUsed[Canonical]);
// Optionally warn if we're emitting a weak vtable.
if (Class->isExternallyVisible() &&
Class->getTemplateSpecializationKind() != TSK_ImplicitInstantiation) {
const FunctionDecl *KeyFunctionDef = nullptr;
if (!KeyFunction ||
(KeyFunction->hasBody(KeyFunctionDef) &&
KeyFunctionDef->isInlined()))
Diag(Class->getLocation(), Class->getTemplateSpecializationKind() ==
TSK_ExplicitInstantiationDefinition
? diag::warn_weak_template_vtable : diag::warn_weak_vtable)
<< Class;
}
}
VTableUses.clear();
return DefinedAnything;
}
void Sema::MarkVirtualMemberExceptionSpecsNeeded(SourceLocation Loc,
const CXXRecordDecl *RD) {
for (const auto *I : RD->methods())
if (I->isVirtual() && !I->isPure())
ResolveExceptionSpec(Loc, I->getType()->castAs<FunctionProtoType>());
}
void Sema::MarkVirtualMembersReferenced(SourceLocation Loc,
const CXXRecordDecl *RD) {
// Mark all functions which will appear in RD's vtable as used.
CXXFinalOverriderMap FinalOverriders;
RD->getFinalOverriders(FinalOverriders);
for (CXXFinalOverriderMap::const_iterator I = FinalOverriders.begin(),
E = FinalOverriders.end();
I != E; ++I) {
for (OverridingMethods::const_iterator OI = I->second.begin(),
OE = I->second.end();
OI != OE; ++OI) {
assert(OI->second.size() > 0 && "no final overrider");
CXXMethodDecl *Overrider = OI->second.front().Method;
// C++ [basic.def.odr]p2:
// [...] A virtual member function is used if it is not pure. [...]
if (!Overrider->isPure())
MarkFunctionReferenced(Loc, Overrider);
}
}
// Only classes that have virtual bases need a VTT.
if (RD->getNumVBases() == 0)
return;
for (const auto &I : RD->bases()) {
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
if (Base->getNumVBases() == 0)
continue;
MarkVirtualMembersReferenced(Loc, Base);
}
}
/// SetIvarInitializers - This routine builds initialization ASTs for the
/// Objective-C implementation whose ivars need be initialized.
void Sema::SetIvarInitializers(ObjCImplementationDecl *ObjCImplementation) {
if (!getLangOpts().CPlusPlus)
return;
if (ObjCInterfaceDecl *OID = ObjCImplementation->getClassInterface()) {
SmallVector<ObjCIvarDecl*, 8> ivars;
CollectIvarsToConstructOrDestruct(OID, ivars);
if (ivars.empty())
return;
SmallVector<CXXCtorInitializer*, 32> AllToInit;
for (unsigned i = 0; i < ivars.size(); i++) {
FieldDecl *Field = ivars[i];
if (Field->isInvalidDecl())
continue;
CXXCtorInitializer *Member;
InitializedEntity InitEntity = InitializedEntity::InitializeMember(Field);
InitializationKind InitKind =
InitializationKind::CreateDefault(ObjCImplementation->getLocation());
InitializationSequence InitSeq(*this, InitEntity, InitKind, None);
ExprResult MemberInit =
InitSeq.Perform(*this, InitEntity, InitKind, None);
MemberInit = MaybeCreateExprWithCleanups(MemberInit);
// Note, MemberInit could actually come back empty if no initialization
// is required (e.g., because it would call a trivial default constructor)
if (!MemberInit.get() || MemberInit.isInvalid())
continue;
Member =
new (Context) CXXCtorInitializer(Context, Field, SourceLocation(),
SourceLocation(),
MemberInit.getAs<Expr>(),
SourceLocation());
AllToInit.push_back(Member);
// Be sure that the destructor is accessible and is marked as referenced.
if (const RecordType *RecordTy
= Context.getBaseElementType(Field->getType())
->getAs<RecordType>()) {
CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl());
if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
MarkFunctionReferenced(Field->getLocation(), Destructor);
CheckDestructorAccess(Field->getLocation(), Destructor,
PDiag(diag::err_access_dtor_ivar)
<< Context.getBaseElementType(Field->getType()));
}
}
}
ObjCImplementation->setIvarInitializers(Context,
AllToInit.data(), AllToInit.size());
}
}
static
void DelegatingCycleHelper(CXXConstructorDecl* Ctor,
llvm::SmallSet<CXXConstructorDecl*, 4> &Valid,
llvm::SmallSet<CXXConstructorDecl*, 4> &Invalid,
llvm::SmallSet<CXXConstructorDecl*, 4> &Current,
Sema &S) {
if (Ctor->isInvalidDecl())
return;
CXXConstructorDecl *Target = Ctor->getTargetConstructor();
// Target may not be determinable yet, for instance if this is a dependent
// call in an uninstantiated template.
if (Target) {
const FunctionDecl *FNTarget = nullptr;
(void)Target->hasBody(FNTarget);
Target = const_cast<CXXConstructorDecl*>(
cast_or_null<CXXConstructorDecl>(FNTarget));
}
CXXConstructorDecl *Canonical = Ctor->getCanonicalDecl(),
// Avoid dereferencing a null pointer here.
*TCanonical = Target? Target->getCanonicalDecl() : nullptr;
if (!Current.insert(Canonical))
return;
// We know that beyond here, we aren't chaining into a cycle.
if (!Target || !Target->isDelegatingConstructor() ||
Target->isInvalidDecl() || Valid.count(TCanonical)) {
Valid.insert(Current.begin(), Current.end());
Current.clear();
// We've hit a cycle.
} else if (TCanonical == Canonical || Invalid.count(TCanonical) ||
Current.count(TCanonical)) {
// If we haven't diagnosed this cycle yet, do so now.
if (!Invalid.count(TCanonical)) {
S.Diag((*Ctor->init_begin())->getSourceLocation(),
diag::warn_delegating_ctor_cycle)
<< Ctor;
// Don't add a note for a function delegating directly to itself.
if (TCanonical != Canonical)
S.Diag(Target->getLocation(), diag::note_it_delegates_to);
CXXConstructorDecl *C = Target;
while (C->getCanonicalDecl() != Canonical) {
const FunctionDecl *FNTarget = nullptr;
(void)C->getTargetConstructor()->hasBody(FNTarget);
assert(FNTarget && "Ctor cycle through bodiless function");
C = const_cast<CXXConstructorDecl*>(
cast<CXXConstructorDecl>(FNTarget));
S.Diag(C->getLocation(), diag::note_which_delegates_to);
}
}
Invalid.insert(Current.begin(), Current.end());
Current.clear();
} else {
DelegatingCycleHelper(Target, Valid, Invalid, Current, S);
}
}
void Sema::CheckDelegatingCtorCycles() {
llvm::SmallSet<CXXConstructorDecl*, 4> Valid, Invalid, Current;
for (DelegatingCtorDeclsType::iterator
I = DelegatingCtorDecls.begin(ExternalSource),
E = DelegatingCtorDecls.end();
I != E; ++I)
DelegatingCycleHelper(*I, Valid, Invalid, Current, *this);
for (llvm::SmallSet<CXXConstructorDecl *, 4>::iterator CI = Invalid.begin(),
CE = Invalid.end();
CI != CE; ++CI)
(*CI)->setInvalidDecl();
}
namespace {
/// \brief AST visitor that finds references to the 'this' expression.
class FindCXXThisExpr : public RecursiveASTVisitor<FindCXXThisExpr> {
Sema &S;
public:
explicit FindCXXThisExpr(Sema &S) : S(S) { }
bool VisitCXXThisExpr(CXXThisExpr *E) {
S.Diag(E->getLocation(), diag::err_this_static_member_func)
<< E->isImplicit();
return false;
}
};
}
bool Sema::checkThisInStaticMemberFunctionType(CXXMethodDecl *Method) {
TypeSourceInfo *TSInfo = Method->getTypeSourceInfo();
if (!TSInfo)
return false;
TypeLoc TL = TSInfo->getTypeLoc();
FunctionProtoTypeLoc ProtoTL = TL.getAs<FunctionProtoTypeLoc>();
if (!ProtoTL)
return false;
// C++11 [expr.prim.general]p3:
// [The expression this] shall not appear before the optional
// cv-qualifier-seq and it shall not appear within the declaration of a
// static member function (although its type and value category are defined
// within a static member function as they are within a non-static member
// function). [ Note: this is because declaration matching does not occur
// until the complete declarator is known. - end note ]
const FunctionProtoType *Proto = ProtoTL.getTypePtr();
FindCXXThisExpr Finder(*this);
// If the return type came after the cv-qualifier-seq, check it now.
if (Proto->hasTrailingReturn() &&
!Finder.TraverseTypeLoc(ProtoTL.getReturnLoc()))
return true;
// Check the exception specification.
if (checkThisInStaticMemberFunctionExceptionSpec(Method))
return true;
return checkThisInStaticMemberFunctionAttributes(Method);
}
bool Sema::checkThisInStaticMemberFunctionExceptionSpec(CXXMethodDecl *Method) {
TypeSourceInfo *TSInfo = Method->getTypeSourceInfo();
if (!TSInfo)
return false;
TypeLoc TL = TSInfo->getTypeLoc();
FunctionProtoTypeLoc ProtoTL = TL.getAs<FunctionProtoTypeLoc>();
if (!ProtoTL)
return false;
const FunctionProtoType *Proto = ProtoTL.getTypePtr();
FindCXXThisExpr Finder(*this);
switch (Proto->getExceptionSpecType()) {
case EST_Uninstantiated:
case EST_Unevaluated:
case EST_BasicNoexcept:
case EST_DynamicNone:
case EST_MSAny:
case EST_None:
break;
case EST_ComputedNoexcept:
if (!Finder.TraverseStmt(Proto->getNoexceptExpr()))
return true;
case EST_Dynamic:
for (const auto &E : Proto->exceptions()) {
if (!Finder.TraverseType(E))
return true;
}
break;
}
return false;
}
bool Sema::checkThisInStaticMemberFunctionAttributes(CXXMethodDecl *Method) {
FindCXXThisExpr Finder(*this);
// Check attributes.
for (const auto *A : Method->attrs()) {
// FIXME: This should be emitted by tblgen.
Expr *Arg = nullptr;
ArrayRef<Expr *> Args;
if (const auto *G = dyn_cast<GuardedByAttr>(A))
Arg = G->getArg();
else if (const auto *G = dyn_cast<PtGuardedByAttr>(A))
Arg = G->getArg();
else if (const auto *AA = dyn_cast<AcquiredAfterAttr>(A))
Args = ArrayRef<Expr *>(AA->args_begin(), AA->args_size());
else if (const auto *AB = dyn_cast<AcquiredBeforeAttr>(A))
Args = ArrayRef<Expr *>(AB->args_begin(), AB->args_size());
else if (const auto *ETLF = dyn_cast<ExclusiveTrylockFunctionAttr>(A)) {
Arg = ETLF->getSuccessValue();
Args = ArrayRef<Expr *>(ETLF->args_begin(), ETLF->args_size());
} else if (const auto *STLF = dyn_cast<SharedTrylockFunctionAttr>(A)) {
Arg = STLF->getSuccessValue();
Args = ArrayRef<Expr *>(STLF->args_begin(), STLF->args_size());
} else if (const auto *LR = dyn_cast<LockReturnedAttr>(A))
Arg = LR->getArg();
else if (const auto *LE = dyn_cast<LocksExcludedAttr>(A))
Args = ArrayRef<Expr *>(LE->args_begin(), LE->args_size());
else if (const auto *RC = dyn_cast<RequiresCapabilityAttr>(A))
Args = ArrayRef<Expr *>(RC->args_begin(), RC->args_size());
else if (const auto *AC = dyn_cast<AcquireCapabilityAttr>(A))
Args = ArrayRef<Expr *>(AC->args_begin(), AC->args_size());
else if (const auto *AC = dyn_cast<TryAcquireCapabilityAttr>(A))
Args = ArrayRef<Expr *>(AC->args_begin(), AC->args_size());
else if (const auto *RC = dyn_cast<ReleaseCapabilityAttr>(A))
Args = ArrayRef<Expr *>(RC->args_begin(), RC->args_size());
if (Arg && !Finder.TraverseStmt(Arg))
return true;
for (unsigned I = 0, N = Args.size(); I != N; ++I) {
if (!Finder.TraverseStmt(Args[I]))
return true;
}
}
return false;
}
void
Sema::checkExceptionSpecification(ExceptionSpecificationType EST,
ArrayRef<ParsedType> DynamicExceptions,
ArrayRef<SourceRange> DynamicExceptionRanges,
Expr *NoexceptExpr,
SmallVectorImpl<QualType> &Exceptions,
FunctionProtoType::ExtProtoInfo &EPI) {
Exceptions.clear();
EPI.ExceptionSpecType = EST;
if (EST == EST_Dynamic) {
Exceptions.reserve(DynamicExceptions.size());
for (unsigned ei = 0, ee = DynamicExceptions.size(); ei != ee; ++ei) {
// FIXME: Preserve type source info.
QualType ET = GetTypeFromParser(DynamicExceptions[ei]);
SmallVector<UnexpandedParameterPack, 2> Unexpanded;
collectUnexpandedParameterPacks(ET, Unexpanded);
if (!Unexpanded.empty()) {
DiagnoseUnexpandedParameterPacks(DynamicExceptionRanges[ei].getBegin(),
UPPC_ExceptionType,
Unexpanded);
continue;
}
// Check that the type is valid for an exception spec, and
// drop it if not.
if (!CheckSpecifiedExceptionType(ET, DynamicExceptionRanges[ei]))
Exceptions.push_back(ET);
}
EPI.NumExceptions = Exceptions.size();
EPI.Exceptions = Exceptions.data();
return;
}
if (EST == EST_ComputedNoexcept) {
// If an error occurred, there's no expression here.
if (NoexceptExpr) {
assert((NoexceptExpr->isTypeDependent() ||
NoexceptExpr->getType()->getCanonicalTypeUnqualified() ==
Context.BoolTy) &&
"Parser should have made sure that the expression is boolean");
if (NoexceptExpr && DiagnoseUnexpandedParameterPack(NoexceptExpr)) {
EPI.ExceptionSpecType = EST_BasicNoexcept;
return;
}
if (!NoexceptExpr->isValueDependent())
NoexceptExpr = VerifyIntegerConstantExpression(NoexceptExpr, nullptr,
diag::err_noexcept_needs_constant_expression,
/*AllowFold*/ false).get();
EPI.NoexceptExpr = NoexceptExpr;
}
return;
}
}
/// IdentifyCUDATarget - Determine the CUDA compilation target for this function
Sema::CUDAFunctionTarget Sema::IdentifyCUDATarget(const FunctionDecl *D) {
// Implicitly declared functions (e.g. copy constructors) are
// __host__ __device__
if (D->isImplicit())
return CFT_HostDevice;
if (D->hasAttr<CUDAGlobalAttr>())
return CFT_Global;
if (D->hasAttr<CUDADeviceAttr>()) {
if (D->hasAttr<CUDAHostAttr>())
return CFT_HostDevice;
return CFT_Device;
}
return CFT_Host;
}
bool Sema::CheckCUDATarget(CUDAFunctionTarget CallerTarget,
CUDAFunctionTarget CalleeTarget) {
// CUDA B.1.1 "The __device__ qualifier declares a function that is...
// Callable from the device only."
if (CallerTarget == CFT_Host && CalleeTarget == CFT_Device)
return true;
// CUDA B.1.2 "The __global__ qualifier declares a function that is...
// Callable from the host only."
// CUDA B.1.3 "The __host__ qualifier declares a function that is...
// Callable from the host only."
if ((CallerTarget == CFT_Device || CallerTarget == CFT_Global) &&
(CalleeTarget == CFT_Host || CalleeTarget == CFT_Global))
return true;
if (CallerTarget == CFT_HostDevice && CalleeTarget != CFT_HostDevice)
return true;
return false;
}
/// HandleMSProperty - Analyze a __delcspec(property) field of a C++ class.
///
MSPropertyDecl *Sema::HandleMSProperty(Scope *S, RecordDecl *Record,
SourceLocation DeclStart,
Declarator &D, Expr *BitWidth,
InClassInitStyle InitStyle,
AccessSpecifier AS,
AttributeList *MSPropertyAttr) {
IdentifierInfo *II = D.getIdentifier();
if (!II) {
Diag(DeclStart, diag::err_anonymous_property);
return nullptr;
}
SourceLocation Loc = D.getIdentifierLoc();
TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
QualType T = TInfo->getType();
if (getLangOpts().CPlusPlus) {
CheckExtraCXXDefaultArguments(D);
if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
UPPC_DataMemberType)) {
D.setInvalidType();
T = Context.IntTy;
TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
}
}
DiagnoseFunctionSpecifiers(D.getDeclSpec());
if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
diag::err_invalid_thread)
<< DeclSpec::getSpecifierName(TSCS);
// Check to see if this name was declared as a member previously
NamedDecl *PrevDecl = nullptr;
LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
LookupName(Previous, S);
switch (Previous.getResultKind()) {
case LookupResult::Found:
case LookupResult::FoundUnresolvedValue:
PrevDecl = Previous.getAsSingle<NamedDecl>();
break;
case LookupResult::FoundOverloaded:
PrevDecl = Previous.getRepresentativeDecl();
break;
case LookupResult::NotFound:
case LookupResult::NotFoundInCurrentInstantiation:
case LookupResult::Ambiguous:
break;
}
if (PrevDecl && PrevDecl->isTemplateParameter()) {
// Maybe we will complain about the shadowed template parameter.
DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
// Just pretend that we didn't see the previous declaration.
PrevDecl = nullptr;
}
if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
PrevDecl = nullptr;
SourceLocation TSSL = D.getLocStart();
const AttributeList::PropertyData &Data = MSPropertyAttr->getPropertyData();
MSPropertyDecl *NewPD = MSPropertyDecl::Create(
Context, Record, Loc, II, T, TInfo, TSSL, Data.GetterId, Data.SetterId);
ProcessDeclAttributes(TUScope, NewPD, D);
NewPD->setAccess(AS);
if (NewPD->isInvalidDecl())
Record->setInvalidDecl();
if (D.getDeclSpec().isModulePrivateSpecified())
NewPD->setModulePrivate();
if (NewPD->isInvalidDecl() && PrevDecl) {
// Don't introduce NewFD into scope; there's already something
// with the same name in the same scope.
} else if (II) {
PushOnScopeChains(NewPD, S);
} else
Record->addDecl(NewPD);
return NewPD;
}