libstdc++-v3/testsuite/20_util/enable_shared_from_this/members/unique_ptr.cc

   1 // { dg-do run { target c++11 } }
   2
   3 // Copyright (C) 2013-2022 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 <memory>
  21 #include <ext/pointer.h>
  22 #include <testsuite_hooks.h>
  23
  24 struct X : public std::enable_shared_from_this<X> { };
  25
  26 void test01()
  27 {
  28   std::unique_ptr<X> up(new X);
  29   X* xp = up.get();
  30   std::shared_ptr<X> sp(std::move(up));
  31   VERIFY( xp->shared_from_this() != nullptr );
  32 }
  33
  34 using __gnu_cxx::_Pointer_adapter;
  35 using __gnu_cxx::_Std_pointer_impl;
  36
  37 struct Deleter
  38 {
  39   struct pointer : _Pointer_adapter<_Std_pointer_impl<X>>
  40   {
  41     using _Pointer_adapter::_Pointer_adapter;
  42     operator X*() const noexcept { return this->get(); }
  43   };
  44
  45   void operator()(pointer p) const noexcept { delete (X*)p; }
  46 };
  47
  48 void test02()
  49 {
  50   std::unique_ptr<X, Deleter> up(new X);
  51   Deleter::pointer xp = up.get();
  52   // Creating shared_ptr from unique_ptr with custom pointer is an extension:
  53   std::shared_ptr<X> sp(std::move(up));
  54   // but enable_shared_from_this should still work:
  55   VERIFY( xp->shared_from_this() != nullptr );
  56 }
  57
  58 int main()
  59 {
  60   test01();
  61   test02();
  62 }