libstdc++-v3/testsuite/23_containers/array/requirements/constexpr_iter.cc

   1 // { dg-options "-std=gnu++2a" }
   2 // { dg-do compile { target c++2a } }
   3 //
   4 // Copyright (C) 2019 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11 //
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16 //
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 #include <array>
  22
  23 constexpr int
  24 test()
  25 {
  26   constexpr std::array<int, 3> a1{{1, 2, 3}};
  27   static_assert(1 == *a1.begin());
  28   auto n = a1[0] * a1[1]* a1[2];
  29   static_assert(1 == *a1.cbegin());
  30
  31   std::array<int, 3> a2{{0, 0, 0}};
  32   std::copy(a1.begin(), a1.end(), a2.begin());
  33
  34   return n;
  35 }
  36
  37 void
  38 run_test()
  39 {
  40   constexpr int n = test();
  41 }