Workaround for PR3173. The fix is correct in the sense that if the enum

code were working correctly, it would be a no-op, but it's not really a 
proper fix.  That said, I don't really want to touch the enum code at 
the moment because I don't understand it very well, and this seems to 
be a relatively visible regression.

llvm-svn: 60680

2 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 9eeaa868a59..341baeab85b 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -430,6 +430,9 @@ bool IntExprEvaluator::VisitDeclRefExpr(const DeclRefExpr *E) {
   // Enums are integer constant exprs.
   if (const EnumConstantDecl *D = dyn_cast<EnumConstantDecl>(E->getDecl())) {
     Result = D->getInitVal();
+    // FIXME: This is an ugly hack around the fact that enums don't set their
+    // signedness consistently; see PR3173
+    Result.setIsUnsigned(!E->getType()->isSignedIntegerType());
     return true;
   }
   
diff --git a/clang/test/Sema/enum.c b/clang/test/Sema/enum.c
index b06882b4d34..5782a43242e 100644
--- a/clang/test/Sema/enum.c
+++ b/clang/test/Sema/enum.c
@@ -55,3 +55,6 @@ enum someenum {};  // expected-warning {{use of empty enum extension}}
 enum e0 { // expected-note {{previous definition is here}}
   E0 = sizeof(enum e0 { E1 }) // expected-error {{nested redefinition}}
 };
+
+// PR3173
+enum { PR3173A, PR3173B = PR3173A+50 };