libstdc++-v3/testsuite/20_util/specialized_algorithms/construct_at/95788.cc

   1 // Copyright (C) 2020-2022 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-options "-std=gnu++2a" }
  19 // { dg-do compile { target c++2a } }
  20 // FIXME [!HOSTED]: avoidable std::allocator usage
  21 // { dg-require-effective-target hosted }
  22
  23 #include <memory>
  24
  25 constexpr bool
  26 test01()
  27 {
  28   const int sz{1};
  29   int* data{std::allocator<int>{}.allocate(sz)};
  30   static_assert(noexcept(std::ranges::construct_at(data, 42)));
  31   std::ranges::construct_at(data, 42);
  32   if (*data != 42)
  33     return false;
  34   std::ranges::destroy_at(data);
  35   std::allocator<int>{}.deallocate(data, sz);
  36   return true;
  37 }
  38
  39 static_assert(test01());
  40
  41 struct S { S(); };
  42 S* p;
  43 static_assert(!noexcept(std::ranges::construct_at(p)));