libstdc++-v3/testsuite/20_util/time_point/cons/81468.cc

   1 // Copyright (C) 2017-2019 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-do compile { target c++11 } }
  19
  20 #include <chrono>
  21 #include <type_traits>
  22
  23 using namespace std;
  24 using namespace std::chrono;
  25
  26 template <class Duration>
  27     using sys_time = time_point<system_clock, Duration>;
  28
  29 static_assert(is_constructible<sys_time<milliseconds>, sys_time<seconds>>{},
  30     "Can construct time_point from one with lower precision duration");
  31
  32 // PR libstdc++/81468 - DR 1177
  33 static_assert(!is_constructible<sys_time<seconds>, sys_time<milliseconds>>{},
  34     "Cannot construct time_point from one with higher precision duration");