libstdc++-v3/testsuite/23_containers/map/56613.cc

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2013-2025 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 <testsuite_hooks.h>
  21 #include <map>
  22
  23 // { dg-do compile { target c++11 } }
  24
  25 // libstdc++/56613
  26
  27 // A conforming C++03 allocator, should still work in C++11 mode.
  28 template<typename T>
  29 struct alloc
  30 {
  31     typedef T value_type;
  32     typedef T* pointer;
  33     typedef const T* const_pointer;
  34     typedef T& reference;
  35     typedef const T& const_reference;
  36     typedef unsigned size_type;
  37     typedef int difference_type;
  38
  39     template<typename U>
  40         struct rebind {
  41             typedef alloc<U> other;
  42         };
  43
  44     alloc() { }
  45     template<typename U>
  46         alloc(const alloc<U>&) { }
  47
  48     pointer allocate(size_type n, const void* = 0) { return
  49 std::allocator<T>().allocate(n); }
  50     void deallocate(pointer p, size_type n) { std::allocator<T>().deallocate(p,
  51 n); }
  52
  53     size_type max_size() const { return -1; }
  54
  55     void construct(pointer p, const T& t) { new ((void*) p) T(t); }
  56     void destroy(pointer p) { p->~T(); }
  57
  58     pointer address(reference x) const throw() { return &x; }
  59     const_pointer address(const_reference x) const throw() { return &x; }
  60 };
  61
  62 template<typename T, typename U>
  63 bool operator==(alloc<T>, alloc<U>) { return true; }
  64
  65 template<typename T, typename U>
  66 bool operator!=(alloc<T>, alloc<U>) { return false; }
  67
  68 int main()
  69 {
  70   std::map<int, int, std::less<int>, alloc<std::pair<const int, int>>> m;
  71   m[1];
  72 }