| // Copyright (C) 2019-2023 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 |
| // <http://www.gnu.org/licenses/>. |
| |
| // { dg-options "-std=gnu++2a" } |
| // { dg-do compile { target c++2a } } |
| |
| #include <span> |
| |
| constexpr bool |
| test01(bool b) |
| { |
| std::span<int, 0> s; |
| if (b || !s.empty()) |
| s.front(); |
| return true; |
| } |
| |
| static_assert(test01(false)); |
| static_assert(test01(true)); // { dg-error "non-constant" } |
| // { dg-error "unreachable" "" { target *-*-* } 0 } |
| // { dg-prune-output "in 'constexpr' expansion" } |
