Fix http://llvm.org/bugs/show_bug.cgi?id=11461.  Credit Alberto Ganesh Barbati.

llvm-svn: 146345
diff --git a/libcxx/include/map b/libcxx/include/map
index abdaa3b..633579b 100644
--- a/libcxx/include/map
+++ b/libcxx/include/map
@@ -381,7 +381,11 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-template <class _Key, class _Tp, class _Compare, bool = is_empty<_Compare>::value>
+template <class _Key, class _Tp, class _Compare, bool = is_empty<_Compare>::value
+#if __has_feature(is_final)
+                                                        && !__is_final(_Compare)
+#endif
+         >
 class __map_value_compare
     : private _Compare
 {