libstdc++-v3/testsuite/23_containers/vector/59829.cc

   1 // Copyright (C) 2014-2025 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++/59829
  21
  22 #include <vector>
  23 #include <testsuite_allocator.h>
  24
  25 // User-defined pointer type that throws if a null pointer is dereferenced.
  26 template<typename T>
  27 struct Pointer : __gnu_test::PointerBase<Pointer<T>, T>
  28 {
  29   using __gnu_test::PointerBase<Pointer<T>, T>::PointerBase;
  30
  31   T& operator*() const
  32   {
  33     if (!this->value)
  34       throw "Dereferenced invalid pointer";
  35     return *this->value;
  36   }
  37 };
  38
  39 // Minimal allocator using Pointer<T>
  40 template<typename T>
  41 struct Alloc
  42 {
  43   typedef T value_type;
  44   typedef Pointer<T> pointer;
  45
  46   Alloc() = default;
  47   template<typename U>
  48     Alloc(const Alloc<U>&) { }
  49
  50   pointer allocate(std::size_t n)
  51   { return pointer(std::allocator<T>().allocate(n)); }
  52
  53   void deallocate(pointer p, std::size_t n)
  54   { std::allocator<T>().deallocate(p.operator->(), n); }
  55 };
  56
  57 template<typename T>
  58 bool operator==(Alloc<T> l, Alloc<T> r) { return true; }
  59
  60 template<typename T>
  61 bool operator!=(Alloc<T> l, Alloc<T> r) { return false; }
  62
  63 int main()
  64 {
  65   std::vector<int, Alloc<int>> a;
  66   (void) a.data();
  67 }