/// Deprecated - Whether this the deprecated conversion of a
/// string literal to a pointer to non-const character data
/// (C++ 4.2p2).
- bool DeprecatedStringLiteralToCharPtr : 1;
+ unsigned DeprecatedStringLiteralToCharPtr : 1;
/// IncompatibleObjC - Whether this is an Objective-C conversion
/// that we should warn about (if we actually use it).
- bool IncompatibleObjC : 1;
+ unsigned IncompatibleObjC : 1;
/// ReferenceBinding - True when this is a reference binding
/// (C++ [over.ics.ref]).
- bool ReferenceBinding : 1;
+ unsigned ReferenceBinding : 1;
/// DirectBinding - True when this is a reference binding that is a
/// direct binding (C++ [dcl.init.ref]).
- bool DirectBinding : 1;
-
- /// RRefBinding - True when this is a reference binding of an rvalue
- /// reference to an rvalue (C++0x [over.ics.rank]p3b4).
- bool RRefBinding : 1;
+ unsigned DirectBinding : 1;
+ /// \brief Whether this is an lvalue reference binding (otherwise, it's
+ /// an rvalue reference binding).
+ unsigned IsLvalueReference : 1;
+
+ /// \brief Whether we're binding to a function lvalue.
+ unsigned BindsToFunctionLvalue : 1;
+
+ /// \brief Whether we're binding to an rvalue.
+ unsigned BindsToRvalue : 1;
+
/// FromType - The type that this conversion is converting
/// from. This is an opaque pointer that can be translated into a
/// QualType.
DeprecatedStringLiteralToCharPtr = false;
ReferenceBinding = false;
DirectBinding = false;
- RRefBinding = false;
+ IsLvalueReference = true;
+ BindsToFunctionLvalue = false;
+ BindsToRvalue = false;
CopyConstructor = 0;
}
return ImplicitConversionSequence::Indistinguishable;
}
+/// \brief Determine whether one of the given reference bindings is better
+/// than the other based on what kind of bindings they are.
+static bool isBetterReferenceBindingKind(const StandardConversionSequence &SCS1,
+ const StandardConversionSequence &SCS2) {
+ // C++0x [over.ics.rank]p3b4:
+ // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an
+ // implicit object parameter of a non-static member function declared
+ // without a ref-qualifier, and *either* S1 binds an rvalue reference
+ // to an rvalue and S2 binds an lvalue reference *or S1 binds an
+ // lvalue reference to a function lvalue and S2 binds an rvalue
+ // reference*.
+ //
+ // FIXME: Rvalue references. We're going rogue with the above edits,
+ // because the semantics in the current C++0x working paper (N3225 at the
+ // time of this writing) break the standard definition of std::forward
+ // and std::reference_wrapper when dealing with references to functions.
+ // Proposed wording changes submitted to CWG for consideration.
+ //
+ // FIXME: Rvalue references. We don't know if we're dealing with the
+ // implicit object parameter, or if the member function in this case has a
+ // ref qualifier. (Of course, we don't have ref qualifiers yet.)
+ return (!SCS1.IsLvalueReference && SCS1.BindsToRvalue &&
+ SCS2.IsLvalueReference) ||
+ (SCS1.IsLvalueReference && SCS1.BindsToFunctionLvalue &&
+ !SCS2.IsLvalueReference);
+}
+
/// CompareStandardConversionSequences - Compare two standard
/// conversion sequences to determine whether one is better than the
/// other or if they are indistinguishable (C++ 13.3.3.2p3).
return QualCK;
if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) {
- // C++0x [over.ics.rank]p3b4:
- // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an
- // implicit object parameter of a non-static member function declared
- // without a ref-qualifier, and S1 binds an rvalue reference to an
- // rvalue and S2 binds an lvalue reference.
- // FIXME: Rvalue references. We don't know if we're dealing with the
- // implicit object parameter, or if the member function in this case has a
- // ref qualifier. (Of course, we don't have ref qualifiers yet.)
- if (SCS1.RRefBinding != SCS2.RRefBinding)
- return SCS1.RRefBinding ? ImplicitConversionSequence::Better
- : ImplicitConversionSequence::Worse;
-
+ // Check for a better reference binding based on the kind of bindings.
+ if (isBetterReferenceBindingKind(SCS1, SCS2))
+ return ImplicitConversionSequence::Better;
+ else if (isBetterReferenceBindingKind(SCS2, SCS1))
+ return ImplicitConversionSequence::Worse;
+
// C++ [over.ics.rank]p3b4:
// -- S1 and S2 are reference bindings (8.5.3), and the types to
// which the references refer are the same type except for
ICS.Standard.setToType(2, T1);
ICS.Standard.ReferenceBinding = true;
ICS.Standard.DirectBinding = true;
- ICS.Standard.RRefBinding = isRValRef && InitCategory.isRValue();
+ ICS.Standard.IsLvalueReference = !isRValRef;
+ ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType();
+ ICS.Standard.BindsToRvalue = false;
ICS.Standard.CopyConstructor = 0;
// Nothing more to do: the inaccessibility/ambiguity check for
ICS.Standard.DirectBinding =
S.getLangOptions().CPlusPlus0x ||
(InitCategory.isPRValue() && !T2->isRecordType());
- ICS.Standard.RRefBinding = isRValRef && InitCategory.isRValue();
+ ICS.Standard.IsLvalueReference = !isRValRef;
+ ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType();
+ ICS.Standard.BindsToRvalue = InitCategory.isRValue();
ICS.Standard.CopyConstructor = 0;
return ICS;
}
// Of course, that's still a reference binding.
if (ICS.isStandard()) {
ICS.Standard.ReferenceBinding = true;
- ICS.Standard.RRefBinding = isRValRef;
+ ICS.Standard.IsLvalueReference = !isRValRef;
+ ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType();
+ ICS.Standard.BindsToRvalue = true;
} else if (ICS.isUserDefined()) {
ICS.UserDefined.After.ReferenceBinding = true;
- ICS.UserDefined.After.RRefBinding = isRValRef;
+ ICS.Standard.IsLvalueReference = !isRValRef;
+ ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType();
+ ICS.Standard.BindsToRvalue = true;
}
return ICS;
ICS.Standard.setAllToTypes(ImplicitParamType);
ICS.Standard.ReferenceBinding = true;
ICS.Standard.DirectBinding = true;
- ICS.Standard.RRefBinding = false;
+
+ // FIXME: Rvalue references.
+ ICS.Standard.IsLvalueReference = true;
+ ICS.Standard.BindsToFunctionLvalue = false;
+ ICS.Standard.BindsToRvalue = false;
return ICS;
}
projects / clang / commitdiff