libstdc++-v3/testsuite/29_atomics/atomic_flag/clear/1.cc

   1 // { dg-do run { target c++11 } }
   2 // { dg-require-thread-fence "" }
   3
   4 // Copyright (C) 2009-2019 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 #include <atomic>
  22 #include <testsuite_hooks.h>
  23
  24 int main()
  25 {
  26   std::atomic_flag f = ATOMIC_FLAG_INIT;
  27
  28   f.clear(); // set to false
  29   VERIFY( false == f.test_and_set() ); // return previous false, set to true
  30   VERIFY( true == f.test_and_set() ); // return true
  31
  32   return 0;
  33 }