libstdc++-v3/testsuite/26_numerics/inner_product/lwg2055.cc

   1 // Copyright (C) 2018-2024 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-do run { target c++20 } }
  19
  20 #include <numeric>
  21 #include <iterator>
  22 #include <testsuite_hooks.h>
  23
  24 struct Int
  25 {
  26   Int(int v) : val(v) { }
  27
  28   ~Int() = default;
  29
  30   Int(const Int& x) : val(x.val), copies(x.copies), moved_from(x.moved_from)
  31   { ++copies; }
  32
  33   Int(Int&& x) : val(x.val), copies(x.copies), moved_from(x.moved_from)
  34   { x.moved_from = true; }
  35
  36   Int& operator=(const Int& x)
  37   {
  38     val = x.val;
  39     copies = x.copies + 1;
  40     moved_from = x.moved_from;
  41     return *this;
  42   }
  43
  44   Int& operator=(Int&& x)
  45   {
  46     val = x.val;
  47     copies = x.copies;
  48     moved_from = x.moved_from;
  49     x.moved_from = true;
  50     return *this;
  51   }
  52
  53   int val = 0;
  54   int copies = 0;
  55   bool moved_from = false;
  56 };
  57
  58 Int operator+(Int x, Int y) { x.val += y.val; return x; }
  59 Int operator*(Int x, Int y) { x.val *= y.val; return x; }
  60
  61 struct Add
  62 {
  63   Int operator()(Int x, Int y) const { x.val += y.val; return x; }
  64 };
  65
  66 struct Multiply
  67 {
  68   Int operator()(Int x, Int y) const { x.val *= y.val; return x; }
  69 };
  70
  71 void
  72 test01()
  73 {
  74   Int i[] = { 0, 1, 2, 3, 4 };
  75   Int j[] = { 5, 6, 7, 8, 9 };
  76   Int res = std::inner_product(std::begin(i), std::end(i), std::begin(j),
  77                                Int{0});
  78   VERIFY( res.copies == 0 );
  79   VERIFY( !res.moved_from );
  80   for (const auto& r : i)
  81     VERIFY( !r.moved_from );
  82   for (const auto& r : j)
  83     VERIFY( !r.moved_from );
  84 }
  85
  86 void
  87 test02()
  88 {
  89   Int i[] = { 0, 1, 2, 3, 4 };
  90   Int j[] = { 5, 6, 7, 8, 9 };
  91   Int res = std::inner_product(std::begin(i), std::end(i), std::begin(j),
  92                                Int{0}, Add{}, Multiply{});
  93   VERIFY( res.copies == 0 );
  94   VERIFY( !res.moved_from );
  95   for (const auto& r : i)
  96     VERIFY( !r.moved_from );
  97   for (const auto& r : j)
  98     VERIFY( !r.moved_from );
  99 }
 100
 101 int
 102 main()
 103 {
 104   test01();
 105   test02();
 106 }