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

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@146345 91177308-0d34-0410-b5e6-96231b3b80d8

include/memory

@@ -1848,8 +1848,16 @@ public:
 
 template <class _T1, class _T2, bool = is_same<typename remove_cv<_T1>::type,
                                                      typename remove_cv<_T2>::type>::value,
-                                bool = is_empty<_T1>::value,
-                                bool = is_empty<_T2>::value>
+                                bool = is_empty<_T1>::value
+#if __has_feature(is_final)
+                                       && !__is_final(_T1)
+#endif
+                                ,
+                                bool = is_empty<_T2>::value
+#if __has_feature(is_final)
+                                       && !__is_final(_T2)
+#endif
+         >
 struct __libcpp_compressed_pair_switch;
 
 template <class _T1, class _T2, bool IsSame>