libstdc++-v3/testsuite/20_util/tuple/creation_functions/constexpr_cpp14.cc

   1 // { dg-do compile { target c++14 } }
   2
   3 // Copyright (C) 2017-2020 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 #include <tuple>
  21
  22 // ignore, see LWG 2773 + LWG 2933.
  23 constexpr bool
  24 test_ignore()
  25 {
  26   auto res = std::tie(std::ignore);
  27   std::get<0>(res) = 42;
  28   return true;
  29 }
  30
  31 static_assert(test_ignore(), "test_ignore failure");