FreeChainXenon/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Only set std::enable_shared_from_this member once.

Browse source 
* include/bits/shared_ptr.h (__enable_shared_from_this_helper): Use
	nullptr.
	* include/bits/shared_ptr_base.h (weak_ptr::_M_assign): Don't assign
	if ownership is already shared with a shared_ptr object.
	(__enable_shared_from_this_helper): Use nullptr.
	* testsuite/20_util/enable_shared_from_this/members/const.cc: New.
	* testsuite/20_util/enable_shared_from_this/members/reinit.cc: New.
	* testsuite/20_util/enable_shared_from_this/requirements/
	explicit_instantiation.cc: Instantiate with const and incomplete types.

From-SVN: r227232
This commit is contained in:
Jonathan Wakely 2015-08-26 22:27:00 +01:00 • committed by Jonathan Wakely
parent 2d1a0c68ab
commit 6bc41b268e
6 changed files with 131 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
libstdc++-v3/ChangeLog
View file

@ -1,5 +1,15 @@
2015-08-26 Jonathan Wakely <jwakely@redhat.com>
* include/bits/shared_ptr.h (__enable_shared_from_this_helper): Use
nullptr.
* include/bits/shared_ptr_base.h (weak_ptr::_M_assign): Don't assign
if ownership is already shared with a shared_ptr object.
(__enable_shared_from_this_helper): Use nullptr.
* testsuite/20_util/enable_shared_from_this/members/const.cc: New.
* testsuite/20_util/enable_shared_from_this/members/reinit.cc: New.
* testsuite/20_util/enable_shared_from_this/requirements/
explicit_instantiation.cc: Instantiate with const and incomplete types.
* include/debug/map.h (map::try_emplace, map::insert_or_assign):
Define.
* include/debug/unordered_map (unordered_map::try_emplace,

2
libstdc++-v3/include/bits/shared_ptr.h
View file

@ -588,7 +588,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
const enable_shared_from_this* __pe,
const _Tp1* __px) noexcept
{
if (__pe != 0)
if (__pe != nullptr)
__pe->_M_weak_assign(const_cast<_Tp1*>(__px), __pn);
}

9
libstdc++-v3/include/bits/shared_ptr_base.h
View file

@ -1468,8 +1468,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
void
_M_assign(_Tp* __ptr, const __shared_count<_Lp>& __refcount) noexcept
{
_M_ptr = __ptr;
_M_refcount = __refcount;
if (use_count() == 0)
{
_M_ptr = __ptr;
_M_refcount = __refcount;
}
}
template<typename _Tp1, _Lock_policy _Lp1> friend class __shared_ptr;
@ -1549,7 +1552,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
const __enable_shared_from_this* __pe,
const _Tp1* __px) noexcept
{
if (__pe != 0)
if (__pe != nullptr)
__pe->_M_weak_assign(const_cast<_Tp1*>(__px), __pn);
}

60
libstdc++-v3/testsuite/20_util/enable_shared_from_this/members/const.cc Normal file
View file

@ -0,0 +1,60 @@
// Copyright (C) 2015 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// { dg-options "-std=gnu++11" }
#include <memory>
#include <testsuite_hooks.h>
template<typename T, typename U>
bool
share_ownership(const std::shared_ptr<T>& p1, const std::shared_ptr<U>& p2)
{
return !p1.owner_before(p2) && !p2.owner_before(p1);
}
void
test01()
{
struct X : public std::enable_shared_from_this<X> { };
using CX = const X;
std::shared_ptr<CX> p(new X);
VERIFY( share_ownership(p->shared_from_this(), p) );
p.reset(new CX);
VERIFY( share_ownership(p->shared_from_this(), p) );
auto p2 = std::const_pointer_cast<X>(p)->shared_from_this();
VERIFY( share_ownership(p2, p) );
}
void
test02()
{
struct X;
using CX = const X;
struct X : public std::enable_shared_from_this<CX> { };
std::shared_ptr<CX> p(new X);
VERIFY( share_ownership(p->shared_from_this(), p) );
p.reset(new CX);
VERIFY( share_ownership(p->shared_from_this(), p) );
}
int
main()
{
test01();
test02();
}

49
libstdc++-v3/testsuite/20_util/enable_shared_from_this/members/reinit.cc Normal file
View file

@ -0,0 +1,49 @@
// Copyright (C) 2015 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// { dg-options "-std=gnu++11" }
#include <memory>
#include <testsuite_hooks.h>
struct X : public std::enable_shared_from_this<X> { };
bool
share_ownership(const std::shared_ptr<X>& p1, const std::shared_ptr<X>& p2)
{
return !p1.owner_before(p2) && !p2.owner_before(p1);
}
void
test01()
{
std::shared_ptr<X> p1(new X);
VERIFY( share_ownership( p1->shared_from_this(), p1 ) );
{
std::shared_ptr<X> p2(p1.get(), [](X*){});
// The weak_ptr member of the enable_shared_from_this base should not
// be reset by creating a second control block that owns the pointer.
VERIFY( share_ownership( p2->shared_from_this(), p1 ) );
}
VERIFY( share_ownership( p1->shared_from_this(), p1 ) );
}
int
main()
{
test01();
}

5
libstdc++-v3/testsuite/20_util/enable_shared_from_this/requirements/explicit_instantiation.cc
View file

@ -21,3 +21,8 @@
#include <memory>
template class std::enable_shared_from_this<int>;
template class std::enable_shared_from_this<const int>;
class Incomplete;
template class std::enable_shared_from_this<Incomplete>;
template class std::enable_shared_from_this<const Incomplete>;