Suppress Wsign-conversion for enums with matching underlying type
As reported here: https://bugs.llvm.org/show_bug.cgi?id=34692
A non-defined enum with a backing type was always defaulting to
being treated as a signed type. IN the case where it IS defined,
the signed-ness of the actual items is used.
This patch uses the underlying type's signed-ness in the non-defined
case to test signed-comparision.
Differential Revision: https://reviews.llvm.org/D38145
llvm-svn: 313907
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 87634ad..9561368 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -8171,8 +8171,11 @@
// For enum types, use the known bit width of the enumerators.
if (const EnumType *ET = dyn_cast<EnumType>(T)) {
EnumDecl *Enum = ET->getDecl();
+ // In C++11, enums without definitions can have an explicitly specified
+ // underlying type. Use this type to compute the range.
if (!Enum->isCompleteDefinition())
- return IntRange(C.getIntWidth(QualType(T, 0)), false);
+ return IntRange(C.getIntWidth(QualType(T, 0)),
+ !ET->isSignedIntegerOrEnumerationType());
unsigned NumPositive = Enum->getNumPositiveBits();
unsigned NumNegative = Enum->getNumNegativeBits();