libstdc++-v3/testsuite/23_containers/vector/bool/80893.cc

   1 // Copyright (C) 2017-2025 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 // libstdc++/80893
  21
  22 #include <vector>
  23 #include <testsuite_allocator.h>
  24
  25 struct DereferencedInvalidPointer { };
  26
  27 // User-defined pointer type that throws if a null pointer is dereferenced.
  28 template<typename T>
  29 struct Pointer : __gnu_test::PointerBase<Pointer<T>, T>
  30 {
  31   using __gnu_test::PointerBase<Pointer<T>, T>::PointerBase;
  32
  33   T& operator*() const
  34   {
  35     if (!this->value)
  36       throw DereferencedInvalidPointer();
  37     return *this->value;
  38   }
  39 };
  40
  41 // Minimal allocator using Pointer<T>
  42 template<typename T>
  43 struct Alloc
  44 {
  45   typedef T value_type;
  46   typedef Pointer<T> pointer;
  47
  48   Alloc() = default;
  49   template<typename U>
  50     Alloc(const Alloc<U>&) { }
  51
  52   pointer allocate(std::size_t n)
  53   {
  54     if (n)
  55       return pointer(std::allocator<T>().allocate(n));
  56     return nullptr;
  57   }
  58
  59   void deallocate(pointer p, std::size_t n)
  60   {
  61     if (n)
  62       std::allocator<T>().deallocate(p.operator->(), n);
  63   }
  64 };
  65
  66 template<typename T>
  67 bool operator==(Alloc<T>, Alloc<T>) { return true; }
  68
  69 template<typename T>
  70 bool operator!=(Alloc<T>, Alloc<T>) { return false; }
  71
  72 int main()
  73 {
  74   std::vector<bool, Alloc<bool>> v(0);
  75   std::vector<bool, Alloc<bool>> w(v);
  76 }