[PATCH] libstdc++/98466 Fix _GLIBCXX_DEBUG N3644 integration

[Jonathan Wakely]

On 01/01/21 18:51 +0100, François Dumont via Libstdc++ wrote:
>I think the PR is not limited to unordered containers iterator, it 
>impacts all _GLIBCXX_DEBUG iterators.
>
>However unordered containers local_iterator was more complicated to 
>handle. Because of c++/65816 I prefer to review _Node_iterator_default 
>constructor to set _M_cur to nullptr even if in principle it is not 
>necessary except for the _Local_iterator_base constructor when hash 
>code is not cached.
>
>Â Â Â  libstdc++: Implement N3644 for _GLIBCXX_DEBUG iterators
>
>Â Â Â  libstdc++-v3/ChangeLog
>
>Â Â Â Â Â Â Â Â Â Â Â  PR libstdc++/98466
>Â Â Â Â Â Â Â Â Â Â Â  * include/bits/hashtable_policy.h (_Node_iterator_base()): 
>Set _M_cur to nullptr.
>Â Â Â Â Â Â Â Â Â Â Â  (_Node_iterator()): Make default.
>Â Â Â Â Â Â Â Â Â Â Â  (_Node_const_iterator()): Make default.
>Â Â Â Â Â Â Â Â Â Â Â  * include/debug/macros.h 
>(__glibcxx_check_erae_range_after): Add _M_singular
>Â Â Â Â Â Â Â Â Â Â Â  iterator checks.
>Â Â Â Â Â Â Â Â Â Â Â  * include/debug/safe_iterator.h
>Â Â Â Â Â Â Â Â Â Â Â  (_GLIBCXX_DEBUG_VERIFY_OPERANDS): Accept if both iterator 
>are value initialized.
>Â Â Â Â Â Â Â Â Â Â Â  * include/debug/safe_local_iterator.h 
>(_GLIBCXX_DEBUG_VERIFY_OPERANDS):
>Â Â Â Â Â Â Â Â Â Â Â  Likewise.
>Â Â Â Â Â Â Â Â Â Â Â  * include/debug/safe_iterator.tcc 
>(_Safe_iterator<>::_M_valid_range): Add
>Â Â Â Â Â Â Â Â Â Â Â  _M_singular checks on input iterators.
>Â Â Â Â Â Â Â Â Â Â Â  * src/c++11/debug.cc 
>(_Safe_iterator_base::_M_can_compare): Remove _M_singular
>Â Â Â Â Â Â Â Â Â Â Â  checks.
>Â Â Â Â Â Â Â Â Â Â Â  * testsuite/23_containers/deque/debug/98466.cc: New test.
>Â Â Â Â Â Â Â Â Â Â Â  * testsuite/23_containers/unordered_map/debug/98466.cc: 
>New test.
>
>Tested under Linux x86_64 normal and debug mode.
>
>Ok to commit ?

Yes, thanks.

One question about the deque test ...


>diff --git a/libstdc++-v3/testsuite/23_containers/deque/debug/98466.cc b/libstdc++-v3/testsuite/23_containers/deque/debug/98466.cc
>new file mode 100644
>index 00000000000..720977e5622
>--- /dev/null
>+++ b/libstdc++-v3/testsuite/23_containers/deque/debug/98466.cc
>@@ -0,0 +1,38 @@
>+// Copyright (C) 2021 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-do run { target c++11 } }

Does this need to be limited to c++11 and later? Could it just use
{ dg-do run } instead?

OK to commit anyway, thanks.