Merge to upstream r225300.

Change-Id: I2b23715db9ac129ff80aa78ad5824db0a4d6fbb3

test/std/utilities/tuple/tuple.tuple/empty_member.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;
+
+// This is not a portable test
+
+#include <tuple>
+
+struct A {};
+
+struct B {};
+
+int main()
+{
+    {
+        typedef std::tuple<int, A> T;
+        static_assert((sizeof(T) == sizeof(int)), "");
+    }
+    {
+        typedef std::tuple<A, int> T;
+        static_assert((sizeof(T) == sizeof(int)), "");
+    }
+    {
+        typedef std::tuple<A, int, B> T;
+        static_assert((sizeof(T) == sizeof(int)), "");
+    }
+    {
+        typedef std::tuple<A, B, int> T;
+        static_assert((sizeof(T) == sizeof(int)), "");
+    }
+    {
+        typedef std::tuple<int, A, B> T;
+        static_assert((sizeof(T) == sizeof(int)), "");
+    }
+}