libstdc++-v3/testsuite/20_util/steady_clock/constexpr_data.cc

// { dg-do compile { target c++11 } }

// Copyright (C) 2010-2021 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 <chrono>
#include <testsuite_common_types.h>

namespace __gnu_test
{
  struct constexpr_member_data
  {
    template<typename _Ttesttype>
      void
      operator()()
      {
	struct _Concept
	{
	  void __constraint()
	  {
	    constexpr auto v1 __attribute__((unused))
	      = _Ttesttype::is_steady;
	  }
	};

	_Concept c;
	c.__constraint();
      }
  };
}

int main()
{
  __gnu_test::constexpr_member_data test;
  test.operator()<std::chrono::steady_clock>();
  return 0;
}