libstdc++-v3/testsuite/25_algorithms/fill_n/constexpr.cc

   1 // Copyright (C) 2019-2023 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
  21 #include <algorithm>
  22 #include <array>
  23
  24 constexpr bool
  25 test()
  26 {
  27   std::array<int, 12> ma0{{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}};
  28
  29   const auto outd = std::fill_n(ma0.begin(), 6, 77);
  30
  31   return outd == ma0.begin() + 6 && ma0[5] == 77 && ma0[6] == 0;
  32 }
  33
  34 static_assert(test());
  35
  36 constexpr bool
  37 test_byte()
  38 {
  39   // PR libstdc++/94933
  40   std::array<char, 12> ma0{};
  41
  42   const auto outd = std::fill_n(ma0.begin(), 6, 77);
  43
  44   return outd == ma0.begin() + 6 && ma0[5] == 77 && ma0[6] == 0;
  45 }
  46
  47 static_assert( test_byte() );
  48
  49 struct S
  50 {
  51   int i = 0;
  52 };
  53
  54 constexpr bool
  55 test_nonscalar()
  56 {
  57   std::array<S, 12> ma0{};
  58
  59   const auto outd = std::fill_n(ma0.begin(), 6, S{77});
  60
  61   return outd == ma0.begin() + 6 && ma0[5].i == 77 && ma0[6].i == 0;
  62 }
  63
  64 static_assert( test_nonscalar() );