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llvm-project/clang/lib/Sema/SemaDeclCXX.cpp
Richard Smith db0ac5572f Split RequireCompleteType into a function that actually requires that the type 
is complete (with an error produced if not) and a function that merely queries
whether the type is complete. Either way we'll trigger instantiation if
necessary, but only the former will diagnose and recover from missing module
imports.

The intent of this change is to prevent a class of bugs where code would call
RequireCompleteType(..., 0) and then ignore the result. With modules, we must
check the return value and use it to determine whether the definition of the
type is visible.

This also fixes a debug info quality issue: calls to isCompleteType do not
trigger the emission of debug information for a type in limited-debug-info
mode. This allows us to avoid emitting debug information for type definitions
in more cases where we believe it is safe to do so.

llvm-svn: 256049
2015-12-18 22:40:25 +00:00

13813 lines
523 KiB
C++
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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 "clang/Sema/Template.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 *SubStmt : Node->children())
IsInvalid |= Visit(SubStmt);
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 we have a throw-all spec at this point, ignore the function.
if (ComputedEST == EST_None)
return;
switch(EST) {
// If this function can throw any exceptions, make a note of that.
case EST_MSAny:
case 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.
case EST_BasicNoexcept:
return;
// If we're still at noexcept(true) and there's a nothrow() callee,
// change to that specification.
case EST_DynamicNone:
if (ComputedEST == EST_BasicNoexcept)
ComputedEST = EST_DynamicNone;
return;
// Check out noexcept specs.
case 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;
}
default:
break;
}
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)).second)
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;
}
// C++11 [dcl.fct.default]p3
// A default argument expression [...] shall not be specified for a
// parameter pack.
if (Param->isParameterPack()) {
Diag(EqualLoc, diag::err_param_default_argument_on_parameter_pack)
<< DefaultArg->getSourceRange();
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,
SourceLocation EqualLoc) {
if (!param)
return;
ParmVarDecl *Param = cast<ParmVarDecl>(param);
Param->setInvalidDecl();
UnparsedDefaultArgLocs.erase(Param);
Param->setDefaultArg(new(Context)
OpaqueValueExpr(EqualLoc,
Param->getType().getNonReferenceType(),
VK_RValue));
}
/// 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;
SourceRange SR;
if (Toks->size() > 1)
SR = SourceRange((*Toks)[1].getLocation(),
Toks->back().getLocation());
else
SR = UnparsedDefaultArgLocs[Param];
Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
<< SR;
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;
// 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->isLocalExternDecl()
? New->getLexicalDeclContext()
: New->getDeclContext();
// Find the previous declaration for the purpose of default arguments.
FunctionDecl *PrevForDefaultArgs = Old;
for (/**/; PrevForDefaultArgs;
// Don't bother looking back past the latest decl if this is a local
// extern declaration; nothing else could work.
PrevForDefaultArgs = New->isLocalExternDecl()
? nullptr
: PrevForDefaultArgs->getPreviousDecl()) {
// Ignore hidden declarations.
if (!LookupResult::isVisible(*this, PrevForDefaultArgs))
continue;
if (S && !isDeclInScope(PrevForDefaultArgs, ScopeDC, S) &&
!New->isCXXClassMember()) {
// Ignore default arguments of old decl if they are not in
// the same scope and this is not an out-of-line definition of
// a member function.
continue;
}
if (PrevForDefaultArgs->isLocalExternDecl() != New->isLocalExternDecl()) {
// If only one of these is a local function declaration, then they are
// declared in different scopes, even though isDeclInScope may think
// they're in the same scope. (If both are local, the scope check is
// sufficent, and if neither is local, then they are in the same scope.)
continue;
}
// We found our guy.
break;
}
// 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 = PrevForDefaultArgs
? PrevForDefaultArgs->getNumParams()
: 0;
p < NumParams; ++p) {
ParmVarDecl *OldParam = PrevForDefaultArgs->getParamDecl(p);
ParmVarDecl *NewParam = New->getParamDecl(p);
bool OldParamHasDfl = OldParam ? OldParam->hasDefaultArg() : false;
bool NewParamHasDfl = NewParam->hasDefaultArg();
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::ext_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 (auto Older = PrevForDefaultArgs;
OldParam->hasInheritedDefaultArg(); /**/) {
Older = Older->getPreviousDecl();
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->hasUnparsedDefaultArg())
NewParam->setUnparsedDefaultArg();
else 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(PrevForDefaultArgs->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->getMostRecentDecl()->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++11 [dcl.fct.default]p4:
// In a given function declaration, each parameter subsequent to a parameter
// with a default argument shall have a default argument supplied in this or
// a previous declaration or shall be a function parameter pack. 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() && !Param->isParameterPack()) {
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()) {
Method = Method->getCanonicalDecl();
Diag(Method->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().CPlusPlus14
? 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().CPlusPlus14
? 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().CPlusPlus14)
break;
if (!Cxx1yLoc.isValid())
Cxx1yLoc = S->getLocStart();
for (Stmt *SubStmt : S->children())
if (SubStmt &&
!CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, 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 *SubStmt : S->children())
if (SubStmt &&
!CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, 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().CPlusPlus14
? 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().CPlusPlus14 &&
(Dcl->getReturnType()->isVoidType() ||
Dcl->getReturnType()->isDependentType());
Diag(Dcl->getLocation(),
OK ? diag::warn_cxx11_compat_constexpr_body_no_return
: diag::err_constexpr_body_no_return);
if (!OK)
return false;
} else if (ReturnStmts.size() > 1) {
Diag(ReturnStmts.back(),
getLangOpts().CPlusPlus14
? 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 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(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;
}
/// Use small set to collect indirect bases. As this is only used
/// locally, there's no need to abstract the small size parameter.
typedef llvm::SmallPtrSet<QualType, 4> IndirectBaseSet;
/// \brief Recursively add the bases of Type. Don't add Type itself.
static void
NoteIndirectBases(ASTContext &Context, IndirectBaseSet &Set,
const QualType &Type)
{
// Even though the incoming type is a base, it might not be
// a class -- it could be a template parm, for instance.
if (auto Rec = Type->getAs<RecordType>()) {
auto Decl = Rec->getAsCXXRecordDecl();
// Iterate over its bases.
for (const auto &BaseSpec : Decl->bases()) {
QualType Base = Context.getCanonicalType(BaseSpec.getType())
.getUnqualifiedType();
if (Set.insert(Base).second)
// If we've not already seen it, recurse.
NoteIndirectBases(Context, Set, Base);
}
}
}
/// \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;
// Used to track indirect bases so we can see if a direct base is
// ambiguous.
IndirectBaseSet IndirectBaseTypes;
// 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];
// Note this base's direct & indirect bases, if there could be ambiguity.
if (NumBases > 1)
NoteIndirectBases(Context, IndirectBaseTypes, NewBaseType);
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);
for (unsigned idx = 0; idx < NumGoodBases; ++idx) {
// Check whether this direct base is inaccessible due to ambiguity.
QualType BaseType = Bases[idx]->getType();
CanQualType CanonicalBase = Context.getCanonicalType(BaseType)
.getUnqualifiedType();
if (IndirectBaseTypes.count(CanonicalBase)) {
CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
/*DetectVirtual=*/true);
bool found
= Class->isDerivedFrom(CanonicalBase->getAsCXXRecordDecl(), Paths);
assert(found);
(void)found;
if (Paths.isAmbiguous(CanonicalBase))
Diag(Bases[idx]->getLocStart (), diag::warn_inaccessible_base_class)
<< BaseType << getAmbiguousPathsDisplayString(Paths)
<< Bases[idx]->getSourceRange();
else
assert(Bases[idx]->isVirtual());
}
// Delete the base class specifier, since its data has been copied
// into the CXXRecordDecl.
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(SourceLocation Loc, 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: In a modules build, do we need the entire path to be visible for us
// to be able to use the inheritance relationship?
if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
return false;
return 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(SourceLocation Loc, 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;
if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
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));
}
/// 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(Loc, 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(Loc, 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 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();
}
void Sema::DiagnoseAbsenceOfOverrideControl(NamedDecl *D) {
if (D->isInvalidDecl() || D->hasAttr<OverrideAttr>())
return;
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
if (!MD || MD->isImplicit() || MD->hasAttr<FinalAttr>() ||
isa<CXXDestructorDecl>(MD))
return;
SourceLocation Loc = MD->getLocation();
SourceLocation SpellingLoc = Loc;
if (getSourceManager().isMacroArgExpansion(Loc))
SpellingLoc = getSourceManager().getImmediateExpansionRange(Loc).first;
SpellingLoc = getSourceManager().getSpellingLoc(SpellingLoc);
if (SpellingLoc.isValid() && getSourceManager().isInSystemHeader(SpellingLoc))
return;
if (MD->size_overridden_methods() > 0) {
Diag(MD->getLocation(), diag::warn_function_marked_not_override_overriding)
<< MD->getDeclName();
const CXXMethodDecl *OMD = *MD->begin_overridden_methods();
Diag(OMD->getLocation(), diag::note_overridden_virtual_function);
}
}
/// 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 {
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) || isa<VarTemplateDecl>(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::SmallPtrSetImpl<ValueDecl*> &Decls;
// List of base classes of the record. Classes are removed after their
// initializers.
llvm::SmallPtrSetImpl<QualType> &BaseClasses;
// Vector of decls to be removed from the Decl set prior to visiting the
// nodes. These Decls may have been initialized in the prior initializer.
llvm::SmallVector<ValueDecl*, 4> DeclsToRemove;
// If non-null, add a note to the warning pointing back to the constructor.
const CXXConstructorDecl *Constructor;
// Variables to hold state when processing an initializer list. When
// InitList is true, special case initialization of FieldDecls matching
// InitListFieldDecl.
bool InitList;
FieldDecl *InitListFieldDecl;
llvm::SmallVector<unsigned, 4> InitFieldIndex;
public:
typedef EvaluatedExprVisitor<UninitializedFieldVisitor> Inherited;
UninitializedFieldVisitor(Sema &S,
llvm::SmallPtrSetImpl<ValueDecl*> &Decls,
llvm::SmallPtrSetImpl<QualType> &BaseClasses)
: Inherited(S.Context), S(S), Decls(Decls), BaseClasses(BaseClasses),
Constructor(nullptr), InitList(false), InitListFieldDecl(nullptr) {}
// Returns true if the use of ME is not an uninitialized use.
bool IsInitListMemberExprInitialized(MemberExpr *ME,
bool CheckReferenceOnly) {
llvm::SmallVector<FieldDecl*, 4> Fields;
bool ReferenceField = false;
while (ME) {
FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
if (!FD)
return false;
Fields.push_back(FD);
if (FD->getType()->isReferenceType())
ReferenceField = true;
ME = dyn_cast<MemberExpr>(ME->getBase()->IgnoreParenImpCasts());
}
// Binding a reference to an unintialized field is not an
// uninitialized use.
if (CheckReferenceOnly && !ReferenceField)
return true;
llvm::SmallVector<unsigned, 4> UsedFieldIndex;
// Discard the first field since it is the field decl that is being
// initialized.
for (auto I = Fields.rbegin() + 1, E = Fields.rend(); I != E; ++I) {
UsedFieldIndex.push_back((*I)->getFieldIndex());
}
for (auto UsedIter = UsedFieldIndex.begin(),
UsedEnd = UsedFieldIndex.end(),
OrigIter = InitFieldIndex.begin(),
OrigEnd = InitFieldIndex.end();
UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
if (*UsedIter < *OrigIter)
return true;
if (*UsedIter > *OrigIter)
break;
}
return false;
}
void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly,
bool AddressOf) {
if (isa<EnumConstantDecl>(ME->getMemberDecl()))
return;
// FieldME is the inner-most MemberExpr that is not an anonymous struct
// or union.
MemberExpr *FieldME = ME;
bool AllPODFields = FieldME->getType().isPODType(S.Context);
Expr *Base = ME;
while (MemberExpr *SubME =
dyn_cast<MemberExpr>(Base->IgnoreParenImpCasts())) {
if (isa<VarDecl>(SubME->getMemberDecl()))
return;
if (FieldDecl *FD = dyn_cast<FieldDecl>(SubME->getMemberDecl()))
if (!FD->isAnonymousStructOrUnion())
FieldME = SubME;
if (!FieldME->getType().isPODType(S.Context))
AllPODFields = false;
Base = SubME->getBase();
}
if (!isa<CXXThisExpr>(Base->IgnoreParenImpCasts()))
return;
if (AddressOf && AllPODFields)
return;
ValueDecl* FoundVD = FieldME->getMemberDecl();
if (ImplicitCastExpr *BaseCast = dyn_cast<ImplicitCastExpr>(Base)) {
while (isa<ImplicitCastExpr>(BaseCast->getSubExpr())) {
BaseCast = cast<ImplicitCastExpr>(BaseCast->getSubExpr());
}
if (BaseCast->getCastKind() == CK_UncheckedDerivedToBase) {
QualType T = BaseCast->getType();
if (T->isPointerType() &&
BaseClasses.count(T->getPointeeType())) {
S.Diag(FieldME->getExprLoc(), diag::warn_base_class_is_uninit)
<< T->getPointeeType() << FoundVD;
}
}
}
if (!Decls.count(FoundVD))
return;
const bool IsReference = FoundVD->getType()->isReferenceType();
if (InitList && !AddressOf && FoundVD == InitListFieldDecl) {
// Special checking for initializer lists.
if (IsInitListMemberExprInitialized(ME, CheckReferenceOnly)) {
return;
}
} else {
// Prevent double warnings on use of unbounded references.
if (CheckReferenceOnly && !IsReference)
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, bool AddressOf) {
E = E->IgnoreParens();
if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
HandleMemberExpr(ME, false /*CheckReferenceOnly*/,
AddressOf /*AddressOf*/);
return;
}
if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
Visit(CO->getCond());
HandleValue(CO->getTrueExpr(), AddressOf);
HandleValue(CO->getFalseExpr(), AddressOf);
return;
}
if (BinaryConditionalOperator *BCO =
dyn_cast<BinaryConditionalOperator>(E)) {
Visit(BCO->getCond());
HandleValue(BCO->getFalseExpr(), AddressOf);
return;
}
if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
HandleValue(OVE->getSourceExpr(), AddressOf);
return;
}
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
switch (BO->getOpcode()) {
default:
break;
case(BO_PtrMemD):
case(BO_PtrMemI):
HandleValue(BO->getLHS(), AddressOf);
Visit(BO->getRHS());
return;
case(BO_Comma):
Visit(BO->getLHS());
HandleValue(BO->getRHS(), AddressOf);
return;
}
}
Visit(E);
}
void CheckInitListExpr(InitListExpr *ILE) {
InitFieldIndex.push_back(0);
for (auto Child : ILE->children()) {
if (InitListExpr *SubList = dyn_cast<InitListExpr>(Child)) {
CheckInitListExpr(SubList);
} else {
Visit(Child);
}
++InitFieldIndex.back();
}
InitFieldIndex.pop_back();
}
void CheckInitializer(Expr *E, const CXXConstructorDecl *FieldConstructor,
FieldDecl *Field, const Type *BaseClass) {
// Remove Decls that may have been initialized in the previous
// initializer.
for (ValueDecl* VD : DeclsToRemove)
Decls.erase(VD);
DeclsToRemove.clear();
Constructor = FieldConstructor;
InitListExpr *ILE = dyn_cast<InitListExpr>(E);
if (ILE && Field) {
InitList = true;
InitListFieldDecl = Field;
InitFieldIndex.clear();
CheckInitListExpr(ILE);
} else {
InitList = false;
Visit(E);
}
if (Field)
Decls.erase(Field);
if (BaseClass)
BaseClasses.erase(BaseClass->getCanonicalTypeInternal());
}
void VisitMemberExpr(MemberExpr *ME) {
// All uses of unbounded reference fields will warn.
HandleMemberExpr(ME, true /*CheckReferenceOnly*/, false /*AddressOf*/);
}
void VisitImplicitCastExpr(ImplicitCastExpr *E) {
if (E->getCastKind() == CK_LValueToRValue) {
HandleValue(E->getSubExpr(), false /*AddressOf*/);
return;
}
Inherited::VisitImplicitCastExpr(E);
}
void VisitCXXConstructExpr(CXXConstructExpr *E) {
if (E->getConstructor()->isCopyConstructor()) {
Expr *ArgExpr = E->getArg(0);
if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
if (ILE->getNumInits() == 1)
ArgExpr = ILE->getInit(0);
if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
if (ICE->getCastKind() == CK_NoOp)
ArgExpr = ICE->getSubExpr();
HandleValue(ArgExpr, false /*AddressOf*/);
return;
}
Inherited::VisitCXXConstructExpr(E);
}
void VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
Expr *Callee = E->getCallee();
if (isa<MemberExpr>(Callee)) {
HandleValue(Callee, false /*AddressOf*/);
for (auto Arg : E->arguments())
Visit(Arg);
return;
}
Inherited::VisitCXXMemberCallExpr(E);
}
void VisitCallExpr(CallExpr *E) {
// Treat std::move as a use.
if (E->getNumArgs() == 1) {
if (FunctionDecl *FD = E->getDirectCallee()) {
if (FD->isInStdNamespace() && FD->getIdentifier() &&
FD->getIdentifier()->isStr("move")) {
HandleValue(E->getArg(0), false /*AddressOf*/);
return;
}
}
}
Inherited::VisitCallExpr(E);
}
void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
Expr *Callee = E->getCallee();
if (isa<UnresolvedLookupExpr>(Callee))
return Inherited::VisitCXXOperatorCallExpr(E);
Visit(Callee);
for (auto Arg : E->arguments())
HandleValue(Arg->IgnoreParenImpCasts(), false /*AddressOf*/);
}
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())
DeclsToRemove.push_back(FD);
if (E->isCompoundAssignmentOp()) {
HandleValue(E->getLHS(), false /*AddressOf*/);
Visit(E->getRHS());
return;
}
Inherited::VisitBinaryOperator(E);
}
void VisitUnaryOperator(UnaryOperator *E) {
if (E->isIncrementDecrementOp()) {
HandleValue(E->getSubExpr(), false /*AddressOf*/);
return;
}
if (E->getOpcode() == UO_AddrOf) {
if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getSubExpr())) {
HandleValue(ME->getBase(), true /*AddressOf*/);
return;
}
}
Inherited::VisitUnaryOperator(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();
if (RD->getDescribedClassTemplate())
return;
// 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());
}
}
llvm::SmallPtrSet<QualType, 4> UninitializedBaseClasses;
for (auto I : RD->bases())
UninitializedBaseClasses.insert(I.getType().getCanonicalType());
if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
return;
UninitializedFieldVisitor UninitializedChecker(SemaRef,
UninitializedFields,
UninitializedBaseClasses);
for (const auto *FieldInit : Constructor->inits()) {
if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
break;
Expr *InitExpr = FieldInit->getInit();
if (!InitExpr)
continue;
if (CXXDefaultInitExpr *Default =
dyn_cast<CXXDefaultInitExpr>(InitExpr)) {
InitExpr = Default->getExpr();
if (!InitExpr)
continue;
// In class initializers will point to the constructor.
UninitializedChecker.CheckInitializer(InitExpr, Constructor,
FieldInit->getAnyMember(),
FieldInit->getBaseClass());
} else {
UninitializedChecker.CheckInitializer(InitExpr, nullptr,
FieldInit->getAnyMember(),
FieldInit->getBaseClass());
}
}
}
} // 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 = dyn_cast<FieldDecl>(D);
assert((isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) &&
"must set init style when field is created");
if (!InitExpr) {
D->setInvalidDecl();
if (FD)
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(ClassDecl->getLocation(),
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) {
ExprResult Res = CorrectDelayedTyposInExpr(Init);
if (!Res.isUsable())
return true;
Init = Res.get();
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;
if (R.empty() && BaseType.isNull() &&
(Corr = CorrectTypo(
R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
llvm::make_unique<MemInitializerValidatorCCC>(ClassDecl),
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);
MarkAnyDeclReferenced(TyD->getLocation(), TyD, /*OdrUse=*/false);
if (SS.isSet()) {
BaseType = Context.getElaboratedType(ETK_None, SS.getScopeRep(),
BaseType);
TInfo = Context.CreateTypeSourceInfo(BaseType);
ElaboratedTypeLoc TL = TInfo->getTypeLoc().castAs<ElaboratedTypeLoc>();
TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
TL.setElaboratedKeywordLoc(SourceLocation());
TL.setQualifierLoc(SS.getWithLocInContext(Context));
}
}
}
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,
/*S*/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()) {
ExprResult DIE =
SemaRef.BuildCXXDefaultInitExpr(Info.Ctor->getLocation(), Field);
if (DIE.isInvalid())
return true;
CXXCtorInitializer *Init;
if (Indirect)
Init = new (SemaRef.Context)
CXXCtorInitializer(SemaRef.Context, Indirect, SourceLocation(),
SourceLocation(), DIE.get(), SourceLocation());
else
Init = new (SemaRef.Context)
CXXCtorInitializer(SemaRef.Context, Field, SourceLocation(),
SourceLocation(), DIE.get(), 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);
DiagnoseUninitializedFields(*this, 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::isAbstractType(SourceLocation Loc, QualType T) {
if (!getLangOpts().CPlusPlus)
return false;
const auto *RD = Context.getBaseElementType(T)->getAsCXXRecordDecl();
if (!RD)
return false;
// FIXME: Per [temp.inst]p1, we are supposed to trigger instantiation of a
// class template specialization here, but doing so breaks a lot of code.
// 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;
return RD->isAbstract();
}
bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T,
TypeDiagnoser &Diagnoser) {
if (!isAbstractType(Loc, T))
return false;
T = Context.getBaseElementType(T);
Diagnoser.diagnose(*this, Loc, T);
DiagnoseAbstractType(T->getAsCXXRecordDecl());
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).second)
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());
}
}
}
static void ReferenceDllExportedMethods(Sema &S, CXXRecordDecl *Class) {
Attr *ClassAttr = getDLLAttr(Class);
if (!ClassAttr)
return;
assert(ClassAttr->getKind() == attr::DLLExport);
TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
if (TSK == TSK_ExplicitInstantiationDeclaration)
// Don't go any further if this is just an explicit instantiation
// declaration.
return;
for (Decl *Member : Class->decls()) {
auto *MD = dyn_cast<CXXMethodDecl>(Member);
if (!MD)
continue;
if (Member->getAttr<DLLExportAttr>()) {
if (MD->isUserProvided()) {
// Instantiate non-default class member functions ...
// .. except for certain kinds of template specializations.
if (TSK == TSK_ImplicitInstantiation && !ClassAttr->isInherited())
continue;
S.MarkFunctionReferenced(Class->getLocation(), MD);
// The function will be passed to the consumer when its definition is
// encountered.
} else if (!MD->isTrivial() || MD->isExplicitlyDefaulted() ||
MD->isCopyAssignmentOperator() ||
MD->isMoveAssignmentOperator()) {
// Synthesize and instantiate non-trivial implicit methods, explicitly
// defaulted methods, and the copy and move assignment operators. The
// latter are exported even if they are trivial, because the address of
// an operator can be taken and should compare equal accross libraries.
DiagnosticErrorTrap Trap(S.Diags);
S.MarkFunctionReferenced(Class->getLocation(), MD);
if (Trap.hasErrorOccurred()) {
S.Diag(ClassAttr->getLocation(), diag::note_due_to_dllexported_class)
<< Class->getName() << !S.getLangOpts().CPlusPlus11;
break;
}
// There is no later point when we will see the definition of this
// function, so pass it to the consumer now.
S.Consumer.HandleTopLevelDecl(DeclGroupRef(MD));
}
}
}
}
/// \brief Check class-level dllimport/dllexport attribute.
void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
Attr *ClassAttr = getDLLAttr(Class);
// MSVC inherits DLL attributes to partial class template specializations.
if (Context.getTargetInfo().getCXXABI().isMicrosoft() && !ClassAttr) {
if (auto *Spec = dyn_cast<ClassTemplatePartialSpecializationDecl>(Class)) {
if (Attr *TemplateAttr =
getDLLAttr(Spec->getSpecializedTemplate()->getTemplatedDecl())) {
auto *A = cast<InheritableAttr>(TemplateAttr->clone(getASTContext()));
A->setInherited(true);
ClassAttr = A;
}
}
}
if (!ClassAttr)
return;
if (!Class->isExternallyVisible()) {
Diag(Class->getLocation(), diag::err_attribute_dll_not_extern)
<< Class << ClassAttr;
return;
}
if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
!ClassAttr->isInherited()) {
// Diagnose dll attributes on members of class with dll attribute.
for (Decl *Member : Class->decls()) {
if (!isa<VarDecl>(Member) && !isa<CXXMethodDecl>(Member))
continue;
InheritableAttr *MemberAttr = getDLLAttr(Member);
if (!MemberAttr || MemberAttr->isInherited() || Member->isInvalidDecl())
continue;
Diag(MemberAttr->getLocation(),
diag::err_attribute_dll_member_of_dll_class)
<< MemberAttr << ClassAttr;
Diag(ClassAttr->getLocation(), diag::note_previous_attribute);
Member->setInvalidDecl();
}
}
if (Class->getDescribedClassTemplate())
// Don't inherit dll attribute until the template is instantiated.
return;
// The class is either imported or exported.
const bool ClassExported = ClassAttr->getKind() == attr::DLLExport;
const bool ClassImported = !ClassExported;
TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
// Ignore explicit dllexport on explicit class template instantiation declarations.
if (ClassExported && !ClassAttr->isInherited() &&
TSK == TSK_ExplicitInstantiationDeclaration) {
Class->dropAttr<DLLExportAttr>();
return;
}
// Force declaration of implicit members so they can inherit the attribute.
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;
if (MD) {
// Don't process deleted methods.
if (MD->isDeleted())
continue;
if (MD->isInlined()) {
// MinGW does not import or export inline methods.
if (!Context.getTargetInfo().getCXXABI().isMicrosoft())
continue;
// MSVC versions before 2015 don't export the move assignment operators,
// so don't attempt to import them if we have a definition.
if (ClassImported && MD->isMoveAssignmentOperator() &&
!getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015))
continue;
}
}
if (!cast<NamedDecl>(Member)->isExternallyVisible())
continue;
if (!getDLLAttr(Member)) {
auto *NewAttr =
cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
NewAttr->setInherited(true);
Member->addAttr(NewAttr);
}
}
if (ClassExported)
DelayedDllExportClasses.push_back(Class);
}
/// \brief Perform propagation of DLL attributes from a derived class to a
/// templated base class for MS compatibility.
void Sema::propagateDLLAttrToBaseClassTemplate(
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;
}
auto TSK = BaseTemplateSpec->getSpecializationKind();
if (!getDLLAttr(BaseTemplateSpec) &&
(TSK == TSK_Undeclared || TSK == TSK_ExplicitInstantiationDeclaration ||
TSK == TSK_ImplicitInstantiation)) {
// The template hasn't been instantiated yet (or it has, but only as an
// explicit instantiation declaration or implicit instantiation, which means
// we haven't codegenned any members yet), so propagate the attribute.
auto *NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
NewAttr->setInherited(true);
BaseTemplateSpec->addAttr(NewAttr);
// If the template is already instantiated, checkDLLAttributeRedeclaration()
// needs to be run again to work see the new attribute. Otherwise this will
// get run whenever the template is instantiated.
if (TSK != TSK_Undeclared)
checkClassLevelDLLAttribute(BaseTemplateSpec);
return;
}
if (getDLLAttr(BaseTemplateSpec)) {
// The template has already been specialized or instantiated with an
// attribute, explicitly or through propagation. We should not try to change
// it.
return;
}
// The template was previously instantiated or explicitly specialized without
// a dll attribute, It's too late for us to add an attribute, so warn that
// this is unsupported.
Diag(BaseLoc, diag::warn_attribute_dll_instantiated_base_class)
<< BaseTemplateSpec->isExplicitSpecialization();
Diag(ClassAttr->getLocation(), diag::note_attribute);
if (BaseTemplateSpec->isExplicitSpecialization()) {
Diag(BaseTemplateSpec->getLocation(),
diag::note_template_class_explicit_specialization_was_here)
<< BaseTemplateSpec;
} else {
Diag(BaseTemplateSpec->getPointOfInstantiation(),
diag::note_template_class_instantiation_was_here)
<< BaseTemplateSpec;
}
}
/// \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->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);
}
}
bool HasMethodWithOverrideControl = false,
HasOverridingMethodWithoutOverrideControl = false;
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);
if (M->hasAttr<OverrideAttr>())
HasMethodWithOverrideControl = true;
else if (M->size_overridden_methods() > 0)
HasOverridingMethodWithoutOverrideControl = true;
// 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);
}
}
}
}
if (HasMethodWithOverrideControl &&
HasOverridingMethodWithoutOverrideControl) {
// At least one method has the 'override' control declared.
// Diagnose all other overridden methods which do not have 'override' specified on them.
for (auto *M : Record->methods())
DiagnoseAbsenceOfOverrideControl(M);
}
// 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);
checkClassLevelDLLAttribute(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().CPlusPlus14)
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.ExceptionSpec.Type = EST_Unevaluated;
EPI.ExceptionSpec.SourceDecl = 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.
auto ESI = computeImplicitExceptionSpec(*this, Loc, MD).getExceptionSpec();
// Update the type of the special member to use it.
UpdateExceptionSpec(MD, ESI);
// 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(), ESI);
}
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().CPlusPlus14;
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().CPlusPlus14 ? !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.ExceptionSpec.Type = EST_Unevaluated;
EPI.ExceptionSpec.SourceDecl = MD;
MD->setType(Context.getFunctionType(ReturnType,
llvm::makeArrayRef(&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) {
// If the exception specification was explicitly specified but hadn't been
// parsed when the method was defaulted, grab it now.
if (SpecifiedType->getExceptionSpecType() == EST_Unparsed)
SpecifiedType =
MD->getTypeSourceInfo()->getType()->castAs<FunctionProtoType>();
// Compute the implicit exception specification.
CallingConv CC = Context.getDefaultCallingConvention(/*IsVariadic=*/false,
/*IsCXXMethod=*/true);
FunctionProtoType::ExtProtoInfo EPI(CC);
EPI.ExceptionSpec = computeImplicitExceptionSpec(*this, MD->getLocation(), MD)
.getExceptionSpec();
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() {
decltype(DelayedExceptionSpecChecks) Checks;
decltype(DelayedDefaultedMemberExceptionSpecs) Specs;
std::swap(Checks, DelayedExceptionSpecChecks);
std::swap(Specs, DelayedDefaultedMemberExceptionSpecs);
// Perform any deferred checking of exception specifications for virtual
// destructors.
for (auto &Check : Checks)
CheckOverridingFunctionExceptionSpec(Check.first, Check.second);
// Check that any explicitly-defaulted methods have exception specifications
// compatible with their implicit exception specifications.
for (auto &Spec : Specs)
CheckExplicitlyDefaultedMemberExceptionSpec(Spec.first, Spec.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;
if (getLangOpts().CUDA) {
// We should delete the special member in CUDA mode if target inference
// failed.
return inferCUDATargetForImplicitSpecialMember(RD, CSM, MD, SMI.ConstArg,
Diagnose);
}
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;
}
namespace {
struct FindHiddenVirtualMethod {
Sema *S;
CXXMethodDecl *Method;
llvm::SmallPtrSet<const CXXMethodDecl *, 8> OverridenAndUsingBaseMethods;
SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
private:
/// Check whether any most overriden method from MD in Methods
static bool CheckMostOverridenMethods(
const CXXMethodDecl *MD,
const llvm::SmallPtrSetImpl<const CXXMethodDecl *> &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;
}
public:
/// 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().
bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
RecordDecl *BaseRecord =
Specifier->getType()->getAs<RecordType>()->getDecl();
DeclarationName Name = 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. Clang deviates from
// GCC by only diagnosing overloads of inherited virtual functions that
// do not override any other virtual functions in the base. GCC's
// -Woverloaded-virtual diagnoses any derived function hiding a virtual
// function from a base class. These cases may be better served by a
// warning (not specific to virtual functions) on call sites when the
// call would select a different function from the base class, were it
// visible.
// See FIXME in test/SemaCXX/warn-overload-virtual.cpp for an example.
if (!S->IsOverload(Method, MD, false))
return true;
// Collect the overload only if its hidden.
if (!CheckMostOverridenMethods(MD, OverridenAndUsingBaseMethods))
overloadedMethods.push_back(MD);
}
}
if (foundSameNameMethod)
OverloadedMethods.append(overloadedMethods.begin(),
overloadedMethods.end());
return foundSameNameMethod;
}
};
} // end anonymous namespace
/// \brief Add the most overriden methods from MD to Methods
static void AddMostOverridenMethods(const CXXMethodDecl *MD,
llvm::SmallPtrSetImpl<const CXXMethodDecl *>& 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);
FindHiddenVirtualMethod FHVM;
FHVM.Method = MD;
FHVM.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, FHVM.OverridenAndUsingBaseMethods);
}
if (DC->lookupInBases(FHVM, Paths))
OverloadedMethods = FHVM.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);
}
static void extendLeft(SourceRange &R, SourceRange Before) {
if (Before.isInvalid())
return;
R.setBegin(Before.getBegin());
if (R.getEnd().isInvalid())
R.setEnd(Before.getEnd());
}
static void extendRight(SourceRange &R, SourceRange After) {
if (After.isInvalid())
return;
if (R.getBegin().isInvalid())
R.setBegin(After.getBegin());
R.setEnd(After.getEnd());
}
/// 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;
}
TypeSourceInfo *ConvTSI = nullptr;
QualType ConvType =
GetTypeFromParser(D.getName().ConversionFunctionId, &ConvTSI);
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) {
bool NeedsTypedef = false;
SourceRange Before, After;
// Walk the chunks and extract information on them for our diagnostic.
bool PastFunctionChunk = false;
for (auto &Chunk : D.type_objects()) {
switch (Chunk.Kind) {
case DeclaratorChunk::Function:
if (!PastFunctionChunk) {
if (Chunk.Fun.HasTrailingReturnType) {
TypeSourceInfo *TRT = nullptr;
GetTypeFromParser(Chunk.Fun.getTrailingReturnType(), &TRT);
if (TRT) extendRight(After, TRT->getTypeLoc().getSourceRange());
}
PastFunctionChunk = true;
break;
}
// Fall through.
case DeclaratorChunk::Array:
NeedsTypedef = true;
extendRight(After, Chunk.getSourceRange());
break;
case DeclaratorChunk::Pointer:
case DeclaratorChunk::BlockPointer:
case DeclaratorChunk::Reference:
case DeclaratorChunk::MemberPointer:
extendLeft(Before, Chunk.getSourceRange());
break;
case DeclaratorChunk::Paren:
extendLeft(Before, Chunk.Loc);
extendRight(After, Chunk.EndLoc);
break;
}
}
SourceLocation Loc = Before.isValid() ? Before.getBegin() :
After.isValid() ? After.getBegin() :
D.getIdentifierLoc();
auto &&DB = Diag(Loc, diag::err_conv_function_with_complex_decl);
DB << Before << After;
if (!NeedsTypedef) {
DB << /*don't need a typedef*/0;
// If we can provide a correct fix-it hint, do so.
if (After.isInvalid() && ConvTSI) {
SourceLocation InsertLoc =
getLocForEndOfToken(ConvTSI->getTypeLoc().getLocEnd());
DB << FixItHint::CreateInsertion(InsertLoc, " ")
<< FixItHint::CreateInsertionFromRange(
InsertLoc, CharSourceRange::getTokenRange(Before))
<< FixItHint::CreateRemoval(Before);
}
} else if (!Proto->getReturnType()->isDependentType()) {
DB << /*typedef*/1 << Proto->getReturnType();
} else if (getLangOpts().CPlusPlus11) {
DB << /*alias template*/2 << Proto->getReturnType();
} else {
DB << /*might not be fixable*/3;
}
// Recover by incorporating the other type chunks into the result type.
// Note, this does *not* change the name of the function. This is compatible
// with the GCC extension:
// struct S { &operator int(); } s;
// int &r = s.operator int(); // ok in GCC
// S::operator int&() {} // error in GCC, function name is 'operator int'.
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(Conversion->getLocation(), 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,
UsingDirectiveDecl *&UD) {
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
// as if by qualified name lookup.
LookupResult R(*this, II, IdentLoc, LookupOrdinaryName, ForRedeclaration);
LookupQualifiedName(R, CurContext->getRedeclContext());
NamedDecl *PrevDecl = R.getAsSingle<NamedDecl>();
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) {
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->getCanonicalDecl() != StdInitializerList->getCanonicalDecl())
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) {
R.clear();
if (TypoCorrection Corrected =
S.CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), Sc, &SS,
llvm::make_unique<NamespaceValidatorCCC>(),
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->isTemplateParamScope())
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");
// The use of a nested name specifier may trigger deprecation warnings.
DiagnoseUseOfDecl(Named, IdentLoc);
// 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;
}
if (isVisible(D))
(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?
}
} else {
auto *FoundRecord = dyn_cast<CXXRecordDecl>(ND);
if (FoundRecord && FoundRecord->isInjectedClassName())
return false;
}
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();
// 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 constructor name lookup finds no
// results, that means the named class has no explicit constructors, and we
// suppressed declaring implicit ones (probably because it's dependent or
// invalid).
if (R.empty() &&
NameInfo.getName().getNameKind() != DeclarationName::CXXConstructorName) {
if (TypoCorrection Corrected = CorrectTypo(
R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
llvm::make_unique<UsingValidatorCCC>(
HasTypenameKeyword, IsInstantiation, SS.getScopeRep(),
dyn_cast<CXXRecordDecl>(CurContext)),
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);
for (auto *Ctor : LookupConstructors(RD))
R.addDecl(Ctor);
} else {
// FIXME: Pick up all the declarations if we found an overloaded function.
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();
// The normal rules do not apply to inheriting constructor declarations.
if (NameInfo.getName().getNameKind() == DeclarationName::CXXConstructorName) {
// Suppress access diagnostics; the access check is instead performed at the
// point of use for an inheriting constructor.
R.suppressDiagnostics();
CheckInheritingConstructorUsingDecl(UD);
return UD;
}
// Otherwise, look up the target name.
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_or_null<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 =
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.
llvm::SmallPtrSet<const CXXRecordDecl *, 4> Bases;
auto Collect = [&Bases](const CXXRecordDecl *Base) {
Bases.insert(Base);
return true;
};
// Collect all bases. Return false if we find a dependent base.
if (!cast<CXXRecordDecl>(CurContext)->forallBases(Collect))
return false;
// Returns true if the base is dependent or is one of the accumulated base
// classes.
auto IsNotBase = [&Bases](const CXXRecordDecl *Base) {
return !Bases.count(Base);
};
// Return 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 (Bases.count(cast<CXXRecordDecl>(NamedContext)) ||
!cast<CXXRecordDecl>(NamedContext)->forallBases(IsNotBase))
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,
Decl *DeclFromDeclSpec) {
// Skip up to the relevant declaration scope.
while (S->isTemplateParamScope())
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);
NewTD->setDescribedAliasTemplate(NewDecl);
NewDecl->setAccess(AS);
if (Invalid)
NewDecl->setInvalidDecl();
else if (OldDecl)
NewDecl->setPreviousDecl(OldDecl);
NewND = NewDecl;
} else {
if (auto *TD = dyn_cast_or_null<TagDecl>(DeclFromDeclSpec)) {
setTagNameForLinkagePurposes(TD, NewTD);
handleTagNumbering(TD, S);
}
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);
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;
}
}
assert(!R.isAmbiguous() && !R.empty());
NamedDecl *ND = R.getFoundDecl();
// Check if we have a previous declaration with the same name.
LookupResult PrevR(*this, Alias, AliasLoc, LookupOrdinaryName,
ForRedeclaration);
LookupName(PrevR, S);
// Check we're not shadowing a template parameter.
if (PrevR.isSingleResult() && PrevR.getFoundDecl()->isTemplateParameter()) {
DiagnoseTemplateParameterShadow(AliasLoc, PrevR.getFoundDecl());
PrevR.clear();
}
// Filter out any other lookup result from an enclosing scope.
FilterLookupForScope(PrevR, CurContext, S, /*ConsiderLinkage*/false,
/*AllowInlineNamespace*/false);
// Find the previous declaration and check that we can redeclare it.
NamespaceAliasDecl *Prev = nullptr;
if (NamedDecl *PrevDecl = PrevR.getAsSingle<NamedDecl>()) {
if (NamespaceAliasDecl *AD = dyn_cast<NamespaceAliasDecl>(PrevDecl)) {
// We already have an alias with the same name that points to the same
// namespace; check that it matches.
if (AD->getNamespace()->Equals(getNamespaceDecl(ND))) {
Prev = AD;
} else if (isVisible(PrevDecl)) {
Diag(AliasLoc, diag::err_redefinition_different_namespace_alias)
<< Alias;
Diag(PrevDecl->getLocation(), diag::note_previous_namespace_alias)
<< AD->getNamespace();
return nullptr;
}
} else if (isVisible(PrevDecl)) {
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;
}
}
// The use of a nested name specifier may trigger deprecation warnings.
DiagnoseUseOfDecl(ND, IdentLoc);
NamespaceAliasDecl *AliasDecl =
NamespaceAliasDecl::Create(Context, CurContext, NamespaceLoc, AliasLoc,
Alias, SS.getWithLocInContext(Context),
IdentLoc, ND);
if (Prev)
AliasDecl->setPreviousDecl(Prev);
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 (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 (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).second;
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();
if (getLangOpts().CUDA) {
inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXDefaultConstructor,
DefaultCon,
/* ConstRHS */ false,
/* Diagnose */ false);
}
// 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;
}
// The exception specification is needed because we are defining the
// function.
ResolveExceptionSpec(CurrentLocation,
Constructor->getType()->castAs<FunctionProtoType>());
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_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.ExceptionSpec.Type = EST_Unevaluated;
EPI.ExceptionSpec.SourceDecl = 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();
if (getLangOpts().CUDA) {
inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXDestructor,
Destructor,
/* ConstRHS */ false,
/* Diagnose */ false);
}
// 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;
}
// The exception specification is needed because we are defining the
// function.
ResolveExceptionSpec(CurrentLocation,
Destructor->getType()->castAs<FunctionProtoType>());
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();
DelayedExceptionSpecChecks.clear();
return;
}
}
}
static void getDefaultArgExprsForConstructors(Sema &S, CXXRecordDecl *Class) {
// Don't do anything for template patterns.
if (Class->getDescribedClassTemplate())
return;
for (Decl *Member : Class->decls()) {
auto *CD = dyn_cast<CXXConstructorDecl>(Member);
if (!CD) {
// Recurse on nested classes.
if (auto *NestedRD = dyn_cast<CXXRecordDecl>(Member))
getDefaultArgExprsForConstructors(S, NestedRD);
continue;
} else if (!CD->isDefaultConstructor() || !CD->hasAttr<DLLExportAttr>()) {
continue;
}
for (unsigned I = 0, E = CD->getNumParams(); I != E; ++I) {
// Skip any default arguments that we've already instantiated.
if (S.Context.getDefaultArgExprForConstructor(CD, I))
continue;
Expr *DefaultArg = S.BuildCXXDefaultArgExpr(Class->getLocation(), CD,
CD->getParamDecl(I)).get();
S.DiscardCleanupsInEvaluationContext();
S.Context.addDefaultArgExprForConstructor(CD, I, DefaultArg);
}
}
}
void Sema::ActOnFinishCXXNonNestedClass(Decl *D) {
auto *RD = dyn_cast<CXXRecordDecl>(D);
// Default constructors that are annotated with __declspec(dllexport) which
// have default arguments or don't use the standard calling convention are
// wrapped with a thunk called the default constructor closure.
if (RD && Context.getTargetInfo().getCXXABI().isMicrosoft())
getDefaultArgExprsForConstructors(*this, RD);
if (!DelayedDllExportClasses.empty()) {
// Calling ReferenceDllExportedMethods might cause the current function to
// be called again, so use a local copy of DelayedDllExportClasses.
SmallVector<CXXRecordDecl *, 4> WorkList;
std::swap(DelayedDllExportClasses, WorkList);
for (CXXRecordDecl *Class : WorkList)
ReferenceDllExportedMethods(*this, Class);
}
}
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.ExceptionSpec.Type = EST_Unevaluated;
EPI.ExceptionSpec.SourceDecl = 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&) = delete;
ExprBuilder &operator=(const ExprBuilder&) = delete;
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:
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:
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:
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:
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:
Expr *build(Sema &S, SourceLocation Loc) const override {
return assertNotNull(S.BuildMemberReferenceExpr(
Builder.build(S, Loc), Type, Loc, IsArrow, SS, SourceLocation(),
nullptr, MemberLookup, nullptr, 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:
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:
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:
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, /*S*/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();
if (getLangOpts().CUDA) {
inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXCopyAssignment,
CopyAssignment,
/* ConstRHS */ Const,
/* Diagnose */ false);
}
// 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()) {
// FIXME: We should form some kind of AST representation for the implied
// memcpy in a union copy operation.
if (Field->isUnnamedBitfield() || Field->getParent()->isUnion())
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;
}
}
}
// The exception specification is needed because we are defining the
// function.
ResolveExceptionSpec(CurrentLocation,
CopyAssignOperator->getType()->castAs<FunctionProtoType>());
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();
if (getLangOpts().CUDA) {
inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXMoveAssignment,
MoveAssignment,
/* ConstRHS */ false,
/* Diagnose */ false);
}
// 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()) {
// FIXME: We should form some kind of AST representation for the implied
// memcpy in a union copy operation.
if (Field->isUnnamedBitfield() || Field->getParent()->isUnion())
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;
}
}
}
// The exception specification is needed because we are defining the
// function.
ResolveExceptionSpec(CurrentLocation,
MoveAssignOperator->getType()->castAs<FunctionProtoType>());
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();
if (getLangOpts().CUDA) {
inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXCopyConstructor,
CopyConstructor,
/* ConstRHS */ Const,
/* Diagnose */ false);
}
// 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>());
}
// The exception specification is needed because we are defining the
// function.
ResolveExceptionSpec(CurrentLocation,
CopyConstructor->getType()->castAs<FunctionProtoType>());
CopyConstructor->markUsed(Context);
MarkVTableUsed(CurrentLocation, ClassDecl);
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();
if (getLangOpts().CUDA) {
inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXMoveConstructor,
MoveConstructor,
/* ConstRHS */ false,
/* Diagnose */ false);
}
// 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>());
}
// The exception specification is needed because we are defining the
// function.
ResolveExceptionSpec(CurrentLocation,
MoveConstructor->getType()->castAs<FunctionProtoType>());
MoveConstructor->markUsed(Context);
MarkVTableUsed(CurrentLocation, ClassDecl);
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 IsStdInitListInitialization,
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,
IsStdInitListInitialization, 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 IsStdInitListInitialization,
bool RequiresZeroInit,
unsigned ConstructKind,
SourceRange ParenRange) {
MarkFunctionReferenced(ConstructLoc, Constructor);
return CXXConstructExpr::Create(
Context, DeclInitType, ConstructLoc, Constructor, Elidable, ExprArgs,
HadMultipleCandidates, IsListInitialization, IsStdInitListInitialization,
RequiresZeroInit,
static_cast<CXXConstructExpr::ConstructionKind>(ConstructKind),
ParenRange);
}
ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
assert(Field->hasInClassInitializer());
// If we already have the in-class initializer nothing needs to be done.
if (Field->getInClassInitializer())
return CXXDefaultInitExpr::Create(Context, Loc, Field);
// Maybe we haven't instantiated the in-class initializer. Go check the
// pattern FieldDecl to see if it has one.
CXXRecordDecl *ParentRD = cast<CXXRecordDecl>(Field->getParent());
if (isTemplateInstantiation(ParentRD->getTemplateSpecializationKind())) {
CXXRecordDecl *ClassPattern = ParentRD->getTemplateInstantiationPattern();
DeclContext::lookup_result Lookup =
ClassPattern->lookup(Field->getDeclName());
assert(Lookup.size() == 1);
FieldDecl *Pattern = cast<FieldDecl>(Lookup[0]);
if (InstantiateInClassInitializer(Loc, Field, Pattern,
getTemplateInstantiationArgs(Field)))
return ExprError();
return CXXDefaultInitExpr::Create(Context, Loc, Field);
}
// 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.
//
// Any attempt to resolve the exception specification of a defaulted default
// constructor before the initializer is lexically complete will ultimately
// come here at which point we can diagnose it.
RecordDecl *OutermostClass = ParentRD->getOuterLexicalRecordContext();
if (OutermostClass == ParentRD) {
Diag(Field->getLocEnd(), diag::err_in_class_initializer_not_yet_parsed)
<< ParentRD << Field;
} else {
Diag(Field->getLocEnd(),
diag::err_in_class_initializer_not_yet_parsed_outer_class)
<< ParentRD << OutermostClass << Field;
}
return ExprError();
}
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(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 = Context.getExceptionObjectType(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(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(),
FriendLoc, 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()) {
int DiagArg = -1;
switch (D.getName().getKind()) {
case UnqualifiedId::IK_ConstructorTemplateId:
case UnqualifiedId::IK_ConstructorName:
DiagArg = 0;
break;
case UnqualifiedId::IK_DestructorName:
DiagArg = 1;
break;
case UnqualifiedId::IK_ConversionFunctionId:
DiagArg = 2;
break;
case UnqualifiedId::IK_Identifier:
case UnqualifiedId::IK_ImplicitSelfParam:
case UnqualifiedId::IK_LiteralOperatorId:
case UnqualifiedId::IK_OperatorFunctionId:
case UnqualifiedId::IK_TemplateId:
break;
}
// This implies that it has to be an operator or function.
if (DiagArg >= 0) {
Diag(Loc, diag::err_introducing_special_friend) << DiagArg;
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() && SS.isValid()) {
Diag(FD->getLocation(), diag::warn_template_qualified_friend_unsupported)
<< SS.getScopeRep() << SS.getRange()
<< cast<CXXRecordDecl>(CurContext);
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);
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 *SubStmt : S->children()) {
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(New->getLocation(), 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;
}
void Sema::ActOnPureSpecifier(Decl *D, SourceLocation ZeroLoc) {
if (D->getFriendObjectKind())
Diag(D->getLocation(), diag::err_pure_friend);
else if (auto *M = dyn_cast<CXXMethodDecl>(D))
CheckPureMethod(M, ZeroLoc);
else
Diag(D->getLocation(), diag::err_illegal_initializer);
}
/// \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 require 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());
if (VTablesUsed[Canonical])
Consumer.HandleVTable(Class);
// 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).second)
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_Unparsed:
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 = llvm::makeArrayRef(AA->args_begin(), AA->args_size());
else if (const auto *AB = dyn_cast<AcquiredBeforeAttr>(A))
Args = llvm::makeArrayRef(AB->args_begin(), AB->args_size());
else if (const auto *ETLF = dyn_cast<ExclusiveTrylockFunctionAttr>(A)) {
Arg = ETLF->getSuccessValue();
Args = llvm::makeArrayRef(ETLF->args_begin(), ETLF->args_size());
} else if (const auto *STLF = dyn_cast<SharedTrylockFunctionAttr>(A)) {
Arg = STLF->getSuccessValue();
Args = llvm::makeArrayRef(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 = llvm::makeArrayRef(LE->args_begin(), LE->args_size());
else if (const auto *RC = dyn_cast<RequiresCapabilityAttr>(A))
Args = llvm::makeArrayRef(RC->args_begin(), RC->args_size());
else if (const auto *AC = dyn_cast<AcquireCapabilityAttr>(A))
Args = llvm::makeArrayRef(AC->args_begin(), AC->args_size());
else if (const auto *AC = dyn_cast<TryAcquireCapabilityAttr>(A))
Args = llvm::makeArrayRef(AC->args_begin(), AC->args_size());
else if (const auto *RC = dyn_cast<ReleaseCapabilityAttr>(A))
Args = llvm::makeArrayRef(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(
bool IsTopLevel, ExceptionSpecificationType EST,
ArrayRef<ParsedType> DynamicExceptions,
ArrayRef<SourceRange> DynamicExceptionRanges, Expr *NoexceptExpr,
SmallVectorImpl<QualType> &Exceptions,
FunctionProtoType::ExceptionSpecInfo &ESI) {
Exceptions.clear();
ESI.Type = 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]);
if (IsTopLevel) {
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);
}
ESI.Exceptions = Exceptions;
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 (IsTopLevel && NoexceptExpr &&
DiagnoseUnexpandedParameterPack(NoexceptExpr)) {
ESI.Type = EST_BasicNoexcept;
return;
}
if (!NoexceptExpr->isValueDependent())
NoexceptExpr = VerifyIntegerConstantExpression(NoexceptExpr, nullptr,
diag::err_noexcept_needs_constant_expression,
/*AllowFold*/ false).get();
ESI.NoexceptExpr = NoexceptExpr;
}
return;
}
}
void Sema::actOnDelayedExceptionSpecification(Decl *MethodD,
ExceptionSpecificationType EST,
SourceRange SpecificationRange,
ArrayRef<ParsedType> DynamicExceptions,
ArrayRef<SourceRange> DynamicExceptionRanges,
Expr *NoexceptExpr) {
if (!MethodD)
return;
// Dig out the method we're referring to.
if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(MethodD))
MethodD = FunTmpl->getTemplatedDecl();
CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(MethodD);
if (!Method)
return;
// Check the exception specification.
llvm::SmallVector<QualType, 4> Exceptions;
FunctionProtoType::ExceptionSpecInfo ESI;
checkExceptionSpecification(/*IsTopLevel*/true, EST, DynamicExceptions,
DynamicExceptionRanges, NoexceptExpr, Exceptions,
ESI);
// Update the exception specification on the function type.
Context.adjustExceptionSpec(Method, ESI, /*AsWritten*/true);
if (Method->isStatic())
checkThisInStaticMemberFunctionExceptionSpec(Method);
if (Method->isVirtual()) {
// Check overrides, which we previously had to delay.
for (CXXMethodDecl::method_iterator O = Method->begin_overridden_methods(),
OEnd = Method->end_overridden_methods();
O != OEnd; ++O)
CheckOverridingFunctionExceptionSpec(Method, *O);
}
}
/// 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;
}
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