N3123

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@119906 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/__tuple b/include/__tuple
index 22134a2..72e36fb 100644
--- a/include/__tuple
+++ b/include/__tuple
@@ -240,7 +240,7 @@
 template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
 struct __tuple_assignable_imp<true, __tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...>>
     : public integral_constant<bool,
-                               __is_assignable<_Up0&, _Tp0>::value &&
+                               is_assignable<_Up0&, _Tp0>::value &&
                                __tuple_assignable_imp<true, __tuple_types<_Tp...>, __tuple_types<_Up...>>::value> {};
 
 template <>