libstdc++-v3/testsuite/21_strings/basic_string/allocator/71964.cc

   1 // Copyright (C) 2016-2022 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++11 } }
  19
  20 #include <string>
  21 #include <testsuite_hooks.h>
  22
  23 template<typename T>
  24   struct mv_allocator
  25   {
  26     using value_type = T;
  27     using size_type = unsigned;
  28
  29     mv_allocator()
  30     : moved_to(false), moved_from(false) { }
  31
  32     template<typename U>
  33       mv_allocator(const mv_allocator<U> & a)
  34       : moved_to(a.moved_to), moved_from(a.moved_from) { }
  35
  36     mv_allocator(const mv_allocator &) = default;
  37
  38     mv_allocator(mv_allocator && a) noexcept : moved_to(true)
  39     {
  40       a.moved_from = true;
  41     }
  42
  43     T* allocate(unsigned n) { return std::allocator<T>{}.allocate(n); }
  44     void deallocate(T* p, unsigned n) { std::allocator<T>{}.deallocate(p, n); }
  45
  46     bool moved_to;
  47     bool moved_from;
  48
  49 #if ! _GLIBCXX_USE_CXX11_ABI
  50     // COW string doesn't use allocator_traits, requires C++03 allocator API.
  51     using pointer = T*;
  52     using const_pointer = const T*;
  53     using difference_type = int;
  54     template<typename U> struct rebind { using other = mv_allocator<U>; };
  55     void construct(pointer p, const T& val) { ::new(p) T(val); }
  56     void destroy(pointer p) { p->~T(); }
  57     size_type max_size() const { return std::allocator<T>().max_size(); }
  58 #endif
  59   };
  60
  61 template<typename T, typename U>
  62 bool
  63 operator==(const mv_allocator<T>&, const mv_allocator<U>&) { return true; }
  64
  65 template<typename T, typename U>
  66 bool
  67 operator!=(const mv_allocator<T>&, const mv_allocator<U>&) { return false; }
  68
  69 void
  70 test01()
  71 {
  72   std::basic_string<char, std::char_traits<char>, mv_allocator<char>> s;
  73   auto t = std::move(s);
  74   VERIFY( s.get_allocator().moved_from );
  75   VERIFY( t.get_allocator().moved_to );
  76 }
  77
  78 int
  79 main()
  80 {
  81   test01();
  82 }