Files
gcc/libstdc++-v3/include/debug/safe_sequence.tcc
François Dumont a1f1a60fc6 libstdc++: [_GLIBCXX_DEBUG] _M_invalidate_if incompatible with C++20 [PR124444]
__gnu_cxx::__scoped_lock cannot be instantiated in a C++20 constexpr function. Use
an intermediate method to avoid this situation.

libstdc++-v3/ChangeLog:
	PR libstdc++/124444
	* include/debug/safe_sequence.h (_Safe_sequence::_M_invalidate_if_impl): New.
	(_Safe_sequence::_M_invalidate_if): Call later if not __is_constant_evaluated.
	* include/debug/safe_sequence.tcc: Rename _M_invalidate_if into
	_M_invalidate_if_impl and remove C++20 constexpr.

Reviewed-by: Jonathan Wakely <jwakely@redhat.com>
2026-03-15 09:13:29 +01:00

157 lines
4.9 KiB
C++

// Safe sequence implementation -*- C++ -*-
// Copyright (C) 2010-2026 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.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file debug/safe_sequence.tcc
* This file is a GNU debug extension to the Standard C++ Library.
*/
#ifndef _GLIBCXX_DEBUG_SAFE_SEQUENCE_TCC
#define _GLIBCXX_DEBUG_SAFE_SEQUENCE_TCC 1
namespace __gnu_debug
{
template<typename _Sequence>
template<typename _Predicate>
void
_Safe_sequence<_Sequence>::
_M_invalidate_if_impl(_Predicate __pred) const
{
typedef typename _Sequence::iterator iterator;
typedef typename _Sequence::const_iterator const_iterator;
__gnu_cxx::__scoped_lock sentry(this->_M_get_mutex());
for (_Safe_iterator_base* __iter = _M_iterators; __iter;)
{
iterator* __victim = static_cast<iterator*>(__iter);
__iter = __iter->_M_next;
if (!__victim->_M_singular() && __pred(__victim->base()))
{
__victim->_M_invalidate();
}
}
for (_Safe_iterator_base* __iter2 = _M_const_iterators; __iter2;)
{
const_iterator* __victim = static_cast<const_iterator*>(__iter2);
__iter2 = __iter2->_M_next;
if (!__victim->_M_singular() && __pred(__victim->base()))
{
__victim->_M_invalidate();
}
}
}
template<typename _Sequence>
template<typename _Predicate>
void
_Safe_sequence<_Sequence>::
_M_transfer_from_if(const _Safe_sequence& __from, _Predicate __pred) const
{
if (this == std::__addressof(__from))
return;
typedef typename _Sequence::iterator iterator;
typedef typename _Sequence::const_iterator const_iterator;
_Safe_iterator_base* __transfered_iterators = 0;
_Safe_iterator_base* __transfered_const_iterators = 0;
_Safe_iterator_base* __last_iterator = 0;
_Safe_iterator_base* __last_const_iterator = 0;
{
// We lock __from first and detach iterator(s) to transfer
__gnu_cxx::__scoped_lock sentry(__from._M_get_mutex());
for (_Safe_iterator_base* __iter = __from._M_iterators; __iter;)
{
_Safe_iterator_base* __victim_base = __iter;
iterator* __victim = static_cast<iterator*>(__victim_base);
__iter = __iter->_M_next;
if (!__victim->_M_singular() && __pred(__victim->base()))
{
__victim->_M_detach_single();
if (__transfered_iterators)
{
__victim_base->_M_next = __transfered_iterators;
__transfered_iterators->_M_prior = __victim_base;
}
else
__last_iterator = __victim_base;
__victim_base->_M_sequence = this;
__victim_base->_M_version = this->_M_version;
__transfered_iterators = __victim_base;
}
}
for (_Safe_iterator_base* __iter2 = __from._M_const_iterators;
__iter2;)
{
_Safe_iterator_base* __victim_base = __iter2;
const_iterator* __victim =
static_cast<const_iterator*>(__victim_base);
__iter2 = __iter2->_M_next;
if (!__victim->_M_singular() && __pred(__victim->base()))
{
__victim->_M_detach_single();
if (__transfered_const_iterators)
{
__victim_base->_M_next = __transfered_const_iterators;
__transfered_const_iterators->_M_prior = __victim_base;
}
else
__last_const_iterator = __victim;
__victim_base->_M_sequence = this;
__victim_base->_M_version = this->_M_version;
__transfered_const_iterators = __victim_base;
}
}
}
// Now we can lock *this and add the transfered iterators if any
if (__last_iterator || __last_const_iterator)
{
__gnu_cxx::__scoped_lock sentry(this->_M_get_mutex());
if (__last_iterator)
{
if (this->_M_iterators)
{
this->_M_iterators->_M_prior = __last_iterator;
__last_iterator->_M_next = this->_M_iterators;
}
this->_M_iterators = __transfered_iterators;
}
if (__last_const_iterator)
{
if (this->_M_const_iterators)
{
this->_M_const_iterators->_M_prior = __last_const_iterator;
__last_const_iterator->_M_next = this->_M_const_iterators;
}
this->_M_const_iterators = __transfered_const_iterators;
}
}
}
} // namespace __gnu_debug
#endif