Fix a null dereference Neil ran into

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@41564 91177308-0d34-0410-b5e6-96231b3b80d8

Sema/SemaDecl.cpp

@@ -965,9 +965,10 @@ Sema::DeclTy *Sema::ParseEnumConstant(Scope *S, DeclTy *theEnumDecl,
            Id->getName());
       // FIXME: Don't leak memory: delete Val;
       Val = 0;  // Just forget about it.
-    }
+    } else {
       EltTy = Val->getType();
     }
+  }
   
   if (!Val) {
     if (LastEnumConst) {