libstdc++-v3/testsuite/20_util/pair/constexpr_assign.cc

   1 // Copyright (C) 2019-2024 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++20 } }
  19
  20 #include <utility>
  21 #include <tuple>
  22
  23 constexpr int
  24 test01(int i, int j)
  25 {
  26   using T = std::tuple<int>;
  27   std::pair<int, int> p0, p1, p2, p3;
  28   std::pair<int, int> pij(std::piecewise_construct, T(i), T(j));
  29   p0 = pij;
  30   p1 = std::move(pij);
  31   std::pair<long, long> pijl(i, j);
  32   p2 = pijl;
  33   p3 = std::move(pijl);
  34   return p0.first + p0.second + p1.first + p1.second
  35     + p2.first + p2.second + p3.first + p3.second;
  36 }
  37
  38 static_assert( test01(3, 100) == 412 );