+// { dg-options "-std=gnu++0x" }
+
+// Copyright (C) 2008, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+
+#include <cstdatomic>
+
+int main()
+{
+ using namespace std;
+ atomic_flag af = ATOMIC_FLAG_INIT;
+
+ if (!af.test_and_set(memory_order_acquire))
+ af.clear(memory_order_release);
+
+ return 0;
+}