Bring inheriting constructor implementation up-to-date with current defect
reports, and implement implicit definition of inheriting constructors.
Remaining missing features: inheriting constructor templates, implicit
exception specifications for inheriting constructors, inheriting constructors
from dependent bases.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177320 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index f66509d..33b701a 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -2642,9 +2642,10 @@
}
// Create a static_cast\<T&&>(expr).
-static Expr *CastForMoving(Sema &SemaRef, Expr *E) {
- QualType ExprType = E->getType();
- QualType TargetType = SemaRef.Context.getRValueReferenceType(ExprType);
+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);
@@ -2659,7 +2660,8 @@
enum ImplicitInitializerKind {
IIK_Default,
IIK_Copy,
- IIK_Move
+ IIK_Move,
+ IIK_Inherit
};
static bool
@@ -2675,6 +2677,35 @@
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.take(), PD->getType()));
+ }
+
+ InitializationKind InitKind = InitializationKind::CreateDirect(
+ Constructor->getLocation(), SourceLocation(), SourceLocation());
+ InitializationSequence InitSeq(SemaRef, InitEntity, InitKind,
+ Args.data(), Args.size());
+ BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, Args);
+ break;
+ }
+ }
+ // Fall through.
case IIK_Default: {
InitializationKind InitKind
= InitializationKind::CreateDefault(Constructor->getLocation());
@@ -2897,7 +2928,8 @@
return false;
}
- assert(ImplicitInitKind == IIK_Default && "Unhandled implicit init kind!");
+ assert((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) &&
+ "Unhandled implicit init kind!");
QualType FieldBaseElementType =
SemaRef.Context.getBaseElementType(Field->getType());
@@ -2988,6 +3020,8 @@
IIK = IIK_Copy;
else if (Generated && Ctor->isMoveConstructor())
IIK = IIK_Move;
+ else if (Ctor->getInheritedConstructor())
+ IIK = IIK_Inherit;
else
IIK = IIK_Default;
}
@@ -2999,6 +3033,7 @@
return true;
case IIK_Default:
+ case IIK_Inherit:
return false;
}
@@ -3226,7 +3261,7 @@
// 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.IIK == IIK_Default)
+ if (F->isAnonymousStructOrUnion() && !Info.isImplicitCopyOrMove())
continue;
if (CollectFieldInitializer(*this, Info, F))
@@ -3235,7 +3270,7 @@
}
// Beyond this point, we only consider default initialization.
- if (Info.IIK != IIK_Default)
+ if (Info.isImplicitCopyOrMove())
continue;
if (IndirectFieldDecl *F = dyn_cast<IndirectFieldDecl>(*Mem)) {
@@ -4062,14 +4097,14 @@
}
}
- // Declare inherited constructors. We do this eagerly here because:
- // - The standard requires an eager diagnostic for conflicting inherited
+ // 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 inherited constructors.
- DeclareInheritedConstructors(Record);
+ // have inheriting constructors.
+ DeclareInheritingConstructors(Record);
}
/// Is the special member function which would be selected to perform the
@@ -4185,7 +4220,9 @@
case Sema::CXXInvalid:
break;
}
- llvm_unreachable("only special members have implicit exception specs");
+ assert(cast<CXXConstructorDecl>(MD)->getInheritedConstructor() &&
+ "only special members have implicit exception specs");
+ return S.ComputeInheritingCtorExceptionSpec(cast<CXXConstructorDecl>(MD));
}
static void
@@ -4194,10 +4231,7 @@
FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
ExceptSpec.getEPI(EPI);
const FunctionProtoType *NewFPT = cast<FunctionProtoType>(
- S.Context.getFunctionType(FPT->getResultType(),
- ArrayRef<QualType>(FPT->arg_type_begin(),
- FPT->getNumArgs()),
- EPI));
+ S.Context.getFunctionType(FPT->getResultType(), FPT->getArgTypes(), EPI));
FD->setType(QualType(NewFPT, 0));
}
@@ -5644,10 +5678,7 @@
EPI.TypeQuals = 0;
EPI.RefQualifier = RQ_None;
- return Context.getFunctionType(Context.VoidTy,
- ArrayRef<QualType>(Proto->arg_type_begin(),
- Proto->getNumArgs()),
- EPI);
+ return Context.getFunctionType(Context.VoidTy, Proto->getArgTypes(), EPI);
}
/// CheckConstructor - Checks a fully-formed constructor for
@@ -6519,9 +6550,7 @@
// C++11 inheriting constructors.
Diag(Name.getLocStart(),
getLangOpts().CPlusPlus11 ?
- // FIXME: Produce warn_cxx98_compat_using_decl_constructor
- // instead once inheriting constructors work.
- diag::err_using_decl_constructor_unsupported :
+ diag::warn_cxx98_compat_using_decl_constructor :
diag::err_using_decl_constructor)
<< SS.getRange();
@@ -6545,7 +6574,7 @@
if (!TargetName)
return 0;
- // Warn about using declarations.
+ // Warn about access declarations.
// TODO: store that the declaration was written without 'using' and
// talk about access decls instead of using decls in the
// diagnostics.
@@ -7471,6 +7500,13 @@
return ExceptSpec;
}
+Sema::ImplicitExceptionSpecification
+Sema::ComputeInheritingCtorExceptionSpec(CXXMethodDecl *MD) {
+ ImplicitExceptionSpecification ExceptSpec(*this);
+ // FIXME: Compute the exception spec.
+ return ExceptSpec;
+}
+
namespace {
/// RAII object to register a special member as being currently declared.
struct DeclaringSpecialMember {
@@ -7597,7 +7633,7 @@
CheckDelayedExplicitlyDefaultedMemberExceptionSpecs();
}
-void Sema::DeclareInheritedConstructors(CXXRecordDecl *ClassDecl) {
+void Sema::DeclareInheritingConstructors(CXXRecordDecl *ClassDecl) {
// We start with an initial pass over the base classes to collect those that
// inherit constructors from. If there are none, we can forgo all further
// processing.
@@ -7612,6 +7648,8 @@
// If we inherit constructors from anything that is dependent, just
// abort processing altogether. We'll get another chance for the
// instantiations.
+ // FIXME: We need to ensure that any call to a constructor of this class
+ // is considered instantiation-dependent in this case.
return;
}
BasesToInheritFrom.push_back(Base->castAs<RecordType>());
@@ -7620,18 +7658,19 @@
if (BasesToInheritFrom.empty())
return;
+ // FIXME: Constructor templates.
+
// Now collect the constructors that we already have in the current class.
// Those take precedence over inherited constructors.
- // C++0x [class.inhctor]p3: [...] a constructor is implicitly declared [...]
+ // 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.
llvm::SmallSet<const Type *, 8> ExistingConstructors;
for (CXXRecordDecl::ctor_iterator CtorIt = ClassDecl->ctor_begin(),
CtorE = ClassDecl->ctor_end();
- CtorIt != CtorE; ++CtorIt) {
+ CtorIt != CtorE; ++CtorIt)
ExistingConstructors.insert(
Context.getCanonicalType(CtorIt->getType()).getTypePtr());
- }
DeclarationName CreatedCtorName =
Context.DeclarationNames.getCXXConstructorName(
@@ -7663,62 +7702,71 @@
SourceLocation UsingLoc = UD ? UD->getLocation() :
ClassDecl->getLocation();
- // C++0x [class.inhctor]p1: The candidate set of inherited constructors
- // from the class X named in the using-declaration consists of actual
- // constructors and notional constructors that result from the
- // transformation of defaulted parameters as follows:
- // - all non-template default constructors of X, and
+ // C++11 [class.inhctor]p1:
+ // The candidate set of inherited constructors from the class X named in
+ // the using-declaration consists of actual constructors and notional
+ // constructors that result from the transformation of defaulted
+ // parameters as follows:
+ // - all non-template constructors of X, and
// - for each non-template constructor of X that has at least one
// parameter with a default argument, the set of constructors that
// results from omitting any ellipsis parameter specification and
// successively omitting parameters with a default argument from the
- // end of the parameter-type-list.
+ // end of the parameter-type-list, and
+ // FIXME: ...also constructor templates.
CXXConstructorDecl *BaseCtor = *CtorIt;
bool CanBeCopyOrMove = BaseCtor->isCopyOrMoveConstructor();
const FunctionProtoType *BaseCtorType =
BaseCtor->getType()->getAs<FunctionProtoType>();
- for (unsigned params = BaseCtor->getMinRequiredArguments(),
- maxParams = BaseCtor->getNumParams();
- params <= maxParams; ++params) {
+ // Determine whether this would be a copy or move constructor for the
+ // derived class.
+ if (BaseCtorType->getNumArgs() >= 1 &&
+ BaseCtorType->getArgType(0)->isReferenceType() &&
+ Context.hasSameUnqualifiedType(
+ BaseCtorType->getArgType(0)->getPointeeType(),
+ Context.getTagDeclType(ClassDecl)))
+ CanBeCopyOrMove = true;
+
+ ArrayRef<QualType> ArgTypes(BaseCtorType->getArgTypes());
+ FunctionProtoType::ExtProtoInfo EPI = BaseCtorType->getExtProtoInfo();
+ // Core issue (no number yet): the ellipsis is always discarded.
+ if (EPI.Variadic) {
+ Diag(UsingLoc, diag::warn_using_decl_constructor_ellipsis);
+ Diag(BaseCtor->getLocation(),
+ diag::note_using_decl_constructor_ellipsis);
+ EPI.Variadic = false;
+ }
+
+ for (unsigned Params = BaseCtor->getMinRequiredArguments(),
+ MaxParams = BaseCtor->getNumParams();
+ Params <= MaxParams; ++Params) {
// Skip default constructors. They're never inherited.
- if (params == 0)
+ if (Params == 0)
continue;
- // Skip copy and move constructors for the same reason.
- if (CanBeCopyOrMove && params == 1)
+
+ // Skip copy and move constructors for both base and derived class
+ // for the same reason.
+ if (CanBeCopyOrMove && Params == 1)
continue;
// Build up a function type for this particular constructor.
- // FIXME: The working paper does not consider that the exception spec
- // for the inheriting constructor might be larger than that of the
- // source. This code doesn't yet, either. When it does, this code will
- // need to be delayed until after exception specifications and in-class
- // member initializers are attached.
- const Type *NewCtorType;
- if (params == maxParams)
- NewCtorType = BaseCtorType;
- else {
- SmallVector<QualType, 16> Args;
- for (unsigned i = 0; i < params; ++i) {
- Args.push_back(BaseCtorType->getArgType(i));
- }
- FunctionProtoType::ExtProtoInfo ExtInfo =
- BaseCtorType->getExtProtoInfo();
- ExtInfo.Variadic = false;
- NewCtorType = Context.getFunctionType(BaseCtorType->getResultType(),
- Args, ExtInfo)
- .getTypePtr();
- }
+ QualType NewCtorType =
+ Context.getFunctionType(Context.VoidTy, ArgTypes.slice(0, Params),
+ EPI);
const Type *CanonicalNewCtorType =
- Context.getCanonicalType(NewCtorType);
+ Context.getCanonicalType(NewCtorType).getTypePtr();
- // Now that we have the type, first check if the class already has a
- // constructor with this signature.
+ // 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 (ExistingConstructors.count(CanonicalNewCtorType))
continue;
- // Then we check if we have already declared an inherited constructor
- // with this signature.
+ // C++11 [class.inhctor]p7:
+ // If two using-declarations declare inheriting constructors with the
+ // same signature, the program is ill-formed
std::pair<ConstructorToSourceMap::iterator, bool> result =
InheritedConstructors.insert(std::make_pair(
CanonicalNewCtorType,
@@ -7740,35 +7788,47 @@
diag::note_using_decl_constructor_conflict_previous_ctor);
Diag(PrevCtor->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.
+ result.first->second.second->setDeletedAsWritten();
}
continue;
}
// OK, we're there, now add the constructor.
- // C++0x [class.inhctor]p8: [...] that would be performed by a
- // user-written inline constructor [...]
DeclarationNameInfo DNI(CreatedCtorName, UsingLoc);
CXXConstructorDecl *NewCtor = CXXConstructorDecl::Create(
- Context, ClassDecl, UsingLoc, DNI, QualType(NewCtorType, 0),
+ Context, ClassDecl, UsingLoc, DNI, NewCtorType,
/*TInfo=*/0, BaseCtor->isExplicit(), /*Inline=*/true,
- /*ImplicitlyDeclared=*/true,
- // FIXME: Due to a defect in the standard, we treat inherited
- // constructors as constexpr even if that makes them ill-formed.
- /*Constexpr=*/BaseCtor->isConstexpr());
+ /*ImplicitlyDeclared=*/true, /*Constexpr=*/BaseCtor->isConstexpr());
NewCtor->setAccess(BaseCtor->getAccess());
+ // Build an unevaluated exception specification for this constructor.
+ EPI.ExceptionSpecType = EST_Unevaluated;
+ EPI.ExceptionSpecDecl = NewCtor;
+ NewCtor->setType(Context.getFunctionType(Context.VoidTy,
+ ArgTypes.slice(0, Params),
+ EPI));
+
// Build up the parameter decls and add them.
SmallVector<ParmVarDecl *, 16> ParamDecls;
- for (unsigned i = 0; i < params; ++i) {
- ParamDecls.push_back(ParmVarDecl::Create(Context, NewCtor,
- UsingLoc, UsingLoc,
- /*IdentifierInfo=*/0,
- BaseCtorType->getArgType(i),
- /*TInfo=*/0, SC_None,
- SC_None, /*DefaultArg=*/0));
+ for (unsigned i = 0; i < Params; ++i) {
+ ParmVarDecl *PD = ParmVarDecl::Create(Context, NewCtor,
+ UsingLoc, UsingLoc,
+ /*IdentifierInfo=*/0,
+ BaseCtorType->getArgType(i),
+ /*TInfo=*/0, SC_None,
+ SC_None, /*DefaultArg=*/0);
+ PD->setScopeInfo(0, i);
+ PD->setImplicit();
+ ParamDecls.push_back(PD);
}
NewCtor->setParams(ParamDecls);
NewCtor->setInheritedConstructor(BaseCtor);
+ if (BaseCtor->isDeleted())
+ NewCtor->setDeletedAsWritten();
ClassDecl->addDecl(NewCtor);
result.first->second.second = NewCtor;
@@ -7777,6 +7837,35 @@
}
}
+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->setUsed();
+ MarkVTableUsed(CurrentLocation, ClassDecl);
+
+ if (ASTMutationListener *L = getASTMutationListener()) {
+ L->CompletedImplicitDefinition(Constructor);
+ }
+}
+
+
Sema::ImplicitExceptionSpecification
Sema::ComputeDefaultedDtorExceptionSpec(CXXMethodDecl *MD) {
CXXRecordDecl *ClassDecl = MD->getParent();