libstdc++-v3/testsuite/20_util/tuple/creation_functions/48476.cc

   1 // { dg-do run { target c++11 } }
   2
   3 // Copyright (C) 2011-2024 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 #include <tuple>
  21 #include <type_traits>
  22 #include <testsuite_hooks.h>
  23
  24 template<typename T>
  25   typename std::decay<T>::type copy(T&& x)
  26   { return std::forward<T>(x); }
  27
  28 template<typename... Args1, typename... Args2>
  29   void
  30   check_tuple_cat(std::tuple<Args1...> t1, std::tuple<Args2...> t2)
  31   {
  32     typedef std::tuple<Args1..., Args2...> concatenated;
  33
  34     auto cat1 = std::tuple_cat(     t1,       t2 );
  35     auto cat2 = std::tuple_cat(copy(t1),      t2 );
  36     auto cat3 = std::tuple_cat(     t1,  copy(t2));
  37     auto cat4 = std::tuple_cat(copy(t1), copy(t2));
  38
  39     static_assert( std::is_same<decltype(cat1), concatenated>::value, "" );
  40     static_assert( std::is_same<decltype(cat2), concatenated>::value, "" );
  41     static_assert( std::is_same<decltype(cat3), concatenated>::value, "" );
  42     static_assert( std::is_same<decltype(cat4), concatenated>::value, "" );
  43
  44     VERIFY( cat1 == cat2 );
  45     VERIFY( cat1 == cat3 );
  46     VERIFY( cat1 == cat4 );
  47   }
  48
  49 // libstdc++/48476
  50 void test01()
  51 {
  52   int i = 0;
  53   std::tuple<> t0;
  54   std::tuple<int&> t1(i);
  55   std::tuple<int&, int> t2(i, 0);
  56   std::tuple<int const&, int, double> t3(i, 0, 0);
  57
  58   check_tuple_cat(t0, t0);
  59   check_tuple_cat(t0, t1);
  60   check_tuple_cat(t0, t2);
  61   check_tuple_cat(t0, t3);
  62
  63   check_tuple_cat(t1, t0);
  64   check_tuple_cat(t1, t1);
  65   check_tuple_cat(t1, t2);
  66   check_tuple_cat(t1, t3);
  67
  68   check_tuple_cat(t2, t0);
  69   check_tuple_cat(t2, t1);
  70   check_tuple_cat(t2, t2);
  71   check_tuple_cat(t2, t3);
  72
  73   check_tuple_cat(t3, t0);
  74   check_tuple_cat(t3, t1);
  75   check_tuple_cat(t3, t2);
  76   check_tuple_cat(t3, t3);
  77 }
  78
  79 int main()
  80 {
  81   test01();
  82   return 0;
  83 }