// { dg-options "-std=gnu++17" } // { dg-do run { target c++17 } } // Copyright (C) 2013-2019 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 // . #include #include struct value_type { int i; }; int main() { { std::optional o = std::nullopt; VERIFY( !o ); } { std::optional o { value_type { 51 } }; VERIFY( o ); } }