Merge to upstream r225300.

Change-Id: I2b23715db9ac129ff80aa78ad5824db0a4d6fbb3

test/std/utilities/tuple/tuple.tuple/tuple.traits/uses_allocator.pass.cpp

@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <tuple>
+
+// template <class... Types> class tuple;
+
+// template <class... Types, class Alloc>
+//   struct uses_allocator<tuple<Types...>, Alloc> : true_type { };
+
+#include <tuple>
+#include <type_traits>
+
+struct A {};
+
+int main()
+{
+    {
+        typedef std::tuple<> T;
+        static_assert((std::is_base_of<std::true_type,
+                                       std::uses_allocator<T, A>>::value), "");
+    }
+    {
+        typedef std::tuple<int> T;
+        static_assert((std::is_base_of<std::true_type,
+                                       std::uses_allocator<T, A>>::value), "");
+    }
+    {
+        typedef std::tuple<char, int> T;
+        static_assert((std::is_base_of<std::true_type,
+                                       std::uses_allocator<T, A>>::value), "");
+    }
+    {
+        typedef std::tuple<double&, char, int> T;
+        static_assert((std::is_base_of<std::true_type,
+                                       std::uses_allocator<T, A>>::value), "");
+    }
+}