Implement pointer to member handling in static_cast.
Fix a stupid mistake in UnwrapSimilarPointers that made any two member pointers compatible as long as the pointee was the same.
Make a few style corrections as suggested by Chris.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@63215 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaNamedCast.cpp b/lib/Sema/SemaNamedCast.cpp
index e88a3b2..cac76b6 100644
--- a/lib/Sema/SemaNamedCast.cpp
+++ b/lib/Sema/SemaNamedCast.cpp
@@ -44,6 +44,8 @@
Sema &Self, Expr *SrcExpr, QualType DestType, const SourceRange &OpRange);
static TryStaticCastResult TryStaticPointerDowncast(
Sema &Self, QualType SrcType, QualType DestType, const SourceRange &OpRange);
+static TryStaticCastResult TryStaticMemberPointerUpcast(
+ Sema &Self, QualType SrcType, QualType DestType, const SourceRange &OpRange);
static TryStaticCastResult TryStaticDowncast(Sema &Self, QualType SrcType,
QualType DestType,
const SourceRange &OpRange,
@@ -479,10 +481,13 @@
return;
}
- // Reverse member pointer conversion. C++ 5.11 specifies member pointer
+ // Reverse member pointer conversion. C++ 4.11 specifies member pointer
// conversion. C++ 5.2.9p9 has additional information.
// DR54's access restrictions apply here also.
- // FIXME: Don't have member pointers yet.
+ if (TryStaticMemberPointerUpcast(Self, SrcType, DestType, OpRange)
+ > TSC_NotApplicable) {
+ return;
+ }
// Reverse pointer conversion to void*. C++ 4.10.p2 specifies conversion to
// void*. C++ 5.2.9p10 specifies additional restrictions, which really is
@@ -655,6 +660,64 @@
return TSC_Success;
}
+/// TryStaticMemberPointerUpcast - Tests whether a conversion according to
+/// C++ 5.2.9p9 is valid:
+///
+/// An rvalue of type "pointer to member of D of type cv1 T" can be
+/// converted to an rvalue of type "pointer to member of B of type cv2 T",
+/// where B is a base class of D [...].
+///
+TryStaticCastResult
+TryStaticMemberPointerUpcast(Sema &Self, QualType SrcType, QualType DestType,
+ const SourceRange &OpRange)
+{
+ const MemberPointerType *SrcMemPtr = SrcType->getAsMemberPointerType();
+ if (!SrcMemPtr)
+ return TSC_NotApplicable;
+ const MemberPointerType *DestMemPtr = DestType->getAsMemberPointerType();
+ if (!DestMemPtr)
+ return TSC_NotApplicable;
+
+ // T == T, modulo cv
+ if (Self.Context.getCanonicalType(
+ SrcMemPtr->getPointeeType().getUnqualifiedType()) !=
+ Self.Context.getCanonicalType(DestMemPtr->getPointeeType().
+ getUnqualifiedType()))
+ return TSC_NotApplicable;
+
+ // B base of D
+ QualType SrcClass(SrcMemPtr->getClass(), 0);
+ QualType DestClass(DestMemPtr->getClass(), 0);
+ BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/false,
+ /*DetectVirtual=*/true);
+ if (!Self.IsDerivedFrom(SrcClass, DestClass, Paths)) {
+ return TSC_NotApplicable;
+ }
+
+ // B is a base of D. But is it an allowed base? If not, it's a hard error.
+ if (Paths.isAmbiguous(DestClass)) {
+ Paths.clear();
+ Paths.setRecordingPaths(true);
+ bool StillOkay = Self.IsDerivedFrom(SrcClass, DestClass, Paths);
+ assert(StillOkay);
+ StillOkay = StillOkay;
+ std::string PathDisplayStr = Self.getAmbiguousPathsDisplayString(Paths);
+ Self.Diag(OpRange.getBegin(), diag::err_ambiguous_memptr_conv)
+ << 1 << SrcClass << DestClass << PathDisplayStr << OpRange;
+ return TSC_Failed;
+ }
+
+ if (const CXXRecordType *VBase = Paths.getDetectedVirtual()) {
+ Self.Diag(OpRange.getBegin(), diag::err_memptr_conv_via_virtual)
+ << SrcClass << DestClass << QualType(VBase, 0) << OpRange;
+ return TSC_Failed;
+ }
+
+ // FIXME: Test accessibility.
+
+ return TSC_Success;
+}
+
/// TryStaticImplicitCast - Tests whether a conversion according to C++ 5.2.9p2
/// is valid:
///