libstdc++-v3/testsuite/20_util/optional/assignment/92878_92947.cc

   1 // { dg-do run { target c++20 } }
   2
   3 // Copyright (C) 2020-2024 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 <optional>
  21 #include <testsuite_hooks.h>
  22
  23 struct aggressive_aggregate
  24 {
  25     int a;
  26     int b;
  27 };
  28
  29 void test01()
  30 {
  31   std::optional<aggressive_aggregate> x;
  32   x.emplace(1, 2);
  33   VERIFY(x->a == 1);
  34   VERIFY(x->b == 2);
  35   x.emplace(1);
  36   VERIFY(x->a == 1);
  37   VERIFY(x->b == 0);
  38   x.emplace();
  39   VERIFY(x->a == 0);
  40   VERIFY(x->b == 0);
  41 }
  42
  43 int main()
  44 {
  45   test01();
  46 }