Clarify the diagnostic for -Wnested-anon-types.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174032 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 24dffc0..80543fd 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -3242,7 +3242,8 @@
           // This is a popular extension, provided by Plan9, MSVC and GCC, but
           // not part of standard C++.
           Diag(MemRecord->getLocation(),
-               diag::ext_anonymous_record_with_anonymous_type);
+               diag::ext_anonymous_record_with_anonymous_type)
+            << (int)Record->isUnion();
         }
       } else if (isa<AccessSpecDecl>(*Mem)) {
         // Any access specifier is fine.