In revision a35dd276cb the debug sequence
have been made mutable to allow attach iterators to const containers.
This change completes this fix by also declaring debug unordered container
members mutable.
Additionally the debug iterator sequence is now a pointer-to-const and so
_Safe_sequence_base _M_attach and all other methods are const qualified.
Not-const methods exported are preserved for abi backward compatibility.
libstdc++-v3/ChangeLog:
PR c++/116369
* config/abi/pre/gnu-versioned-namespace.ver: Use new const qualified symbols.
* config/abi/pre/gnu.ver: Add new const qualified symbols.
* include/debug/safe_base.h
(_Safe_iterator_base::_M_sequence): Declare as pointer-to-const.
(_Safe_iterator_base::_M_attach, _M_attach_single): New, take pointer-to-const
_Safe_sequence_base.
(_Safe_sequence_base::_M_detach_all, _M_detach_singular, _M_revalidate_singular)
(_M_swap, _M_get_mutex): New, const qualified.
(_Safe_sequence_base::_M_attach, _M_attach_single, _M_detach, _M_detach_single):
const qualify.
* include/debug/safe_container.h (_Safe_container<>::_M_cont): Add const qualifier.
(_Safe_container<>::_M_swap_base): New.
(_Safe_container(_Safe_container&&, const _Alloc&, std::false_type)):
Adapt to use latter.
(_Safe_container<>::operator=(_Safe_container&&)): Likewise.
(_Safe_container<>::_M_swap): Likewise and take parameter as const reference.
* include/debug/safe_unordered_base.h
(_Safe_local_iterator_base::_M_safe_container): New.
(_Safe_local_iterator_base::_Safe_local_iterator_base): Take
_Safe_unordered_container_base as pointer-to-const.
(_Safe_unordered_container_base::_M_attach, _M_attach_single): New, take
container as _Safe_unordered_container_base pointer-to-const.
(_Safe_unordered_container_base::_M_local_iterators, _M_const_local_iterators):
Add mutable.
(_Safe_unordered_container_base::_M_detach_all, _M_swap): New, const qualify.
(_Safe_unordered_container_base::_M_attach_local, _M_attach_local_single)
(_M_detach_local, _M_detach_local_single): Add const qualifier.
* include/debug/safe_unordered_container.h (_Safe_unordered_container::_M_self()): New.
* include/debug/safe_unordered_container.tcc
(_Safe_unordered_container::_M_invalidate_if, _M_invalidated_local_if): Use latter.
* include/debug/safe_iterator.h (_Safe_iterator<>::_M_attach, _M_attach_single):
Take _Safe_sequence_base as pointer-to-const.
(_Safe_iterator<>::_M_get_sequence): Add const_cast and comment about it.
* include/debug/safe_local_iterator.h (_Safe_local_iterator<>): Replace usages
of _M_sequence member by _M_safe_container().
(_Safe_local_iterator<>::_M_attach, _M_attach_single): Take
_Safe_unordered_container_base as pointer-to-const.
(_Safe_local_iterator<>::_M_get_sequence): Rename into...
(_Safe_local_iterator<>::_M_get_ucontainer): ...this. Add necessary const_cast and
comment to explain it.
(_Safe_local_iterator<>::_M_is_begin, _M_is_end): Adapt.
* include/debug/safe_local_iterator.tcc: Adapt.
* include/debug/safe_sequence.h
(_Safe_sequence<>::_M_invalidate_if, _M_transfer_from_if): Add const qualifier.
* include/debug/safe_sequence.tcc: Adapt.
* include/debug/deque (std::__debug::deque::erase): Adapt to use new const
qualified methods.
* include/debug/formatter.h: Adapt.
* include/debug/forward_list (_Safe_forward_list::_M_this): Add const
qualification and return pointer for consistency with 'this' keyword.
(_Safe_forward_list::_M_swap_aux): Rename into...
(_Safe_forward_list::_S_swap_aux): ...this and take sequence as const reference.
(forward_list<>::resize): Adapt to use const methods.
* include/debug/list (list<>::resize): Likewise.
* src/c++11/debug.cc: Adapt to const qualification.
* testsuite/util/testsuite_containers.h
(forward_members_unordered::forward_members_unordered): Add check on local_iterator
conversion to const_local_iterator.
(forward_members::forward_members): Add check on iterator conversion to
const_iterator.
* testsuite/23_containers/unordered_map/const_container.cc: New test case.
* testsuite/23_containers/unordered_multimap/const_container.cc: New test case.
* testsuite/23_containers/unordered_multiset/const_container.cc: New test case.
* testsuite/23_containers/unordered_set/const_container.cc: New test case.
* testsuite/23_containers/vector/debug/mutex_association.cc: Adapt.
Creating a safe iterator from a normal iterator is done within the library where we
already know that it is done correctly. The rare situation where a user would use safe
iterators for his own purpose is non-Standard code so outside _GLIBCXX_DEBUG scope. For
those reasons the __msg_init_singular is useless and can be removed.
Additionally in the copy constructor used for post-increment and post-decrement operators
the __msg_init_copy_singular check can also be ommitted because of the preliminary
__msg_bad_incr and __msg_bad_decr checks.
libstdc++-v3/ChangeLog:
* include/debug/safe_iterator.h (_Safe_iterator<>::_Unchecked): New.
(_Safe_iterator(const _Safe_iterator&, _Unchecked)): New.
(_Safe_iterator::operator++(int)): Use latter.
(_Safe_iterator::operator--(int)): Likewise.
(_Safe_iterator(_Iterator, const _Safe_sequence_base*)): Remove !_M_insular()
check.
* include/debug/safe_local_iterator.h (_Safe_local_iterator<>::_Unchecked):
New.
(_Safe_local_iterator(const _Safe_local_iterator&, _Unchecked)): New.
(_Safe_local_iterator::operator++(int)): Use latter.
* src/c++11/debug.cc (_S_debug_messages): Add as comment the _Debug_msg_id
entry associated to the array entry.
An attach iterator has its _M_version set to something != 0, the container version. This
value shall be preserved when detaching it so that the iterator does not look like a
value-initialized one.
libstdc++-v3/ChangeLog:
* include/debug/formatter.h (__singular_value_init): New _Iterator_state enum entry.
(_Parameter<>(const _Safe_iterator<>&, const char*, _Is_iterator)): Check if iterator
parameter is value-initialized.
(_Parameter<>(const _Safe_local_iterator<>&, const char*, _Is_iterator)): Likewise.
* include/debug/safe_iterator.h (_Safe_iterator<>::_M_value_initialized()): New. Adapt
checks.
* include/debug/safe_local_iterator.h (_Safe_local_iterator<>::_M_value_initialized()): New.
Adapt checks.
* src/c++11/debug.cc (_Safe_iterator_base::_M_reset): Do not reset _M_version.
(print_field(PrintContext&, const _Parameter&, const char*)): Adapt state_names.
* testsuite/23_containers/deque/debug/iterator1_neg.cc: New test.
* testsuite/23_containers/deque/debug/iterator2_neg.cc: New test.
* testsuite/23_containers/forward_list/debug/iterator1_neg.cc: New test.
* testsuite/23_containers/forward_list/debug/iterator2_neg.cc: New test.
* testsuite/23_containers/forward_list/debug/iterator3_neg.cc: New test.
The C++ LWG recently confirmed that self-move assignment should not have
undefined behaviour for standard containers (see the proposed resolution
of LWG 2839). The result should be a valid but unspecified value, just
like other times when a container is moved from.
Our std::list, std::__cxx11::basic_string and unordered containers all
have bugs which result in undefined behaviour.
For std::list the problem is that we clear the previous contents using
_M_clear() instead of clear(). This means the _M_next, _M_prev and
_M_size members are not zeroed, and so after we "update" them (with
their existing values), we are left with dangling pointers and a
non-zero size, but no elements.
For the unordered containers the problem is similar. _Hashtable first
deallocates the existing contents, then takes ownership of the pointers
from the RHS object (which has just had its contents deallocated so the
pointers are dangling).
For std::basic_string it's a little more subtle. When the string is
local (i.e. fits in the SSO buffer) we use char_traits::copy to copy the
contents from this->data() to __rhs.data(). When &__rhs == this that
copy violates the precondition that the ranges don't overlap. We only
need to check for self-move for this case where it's local, because the
only other case that can be true for self-move is that it's non-local
but the allocators compare equal. In that case the data pointer is
neither deallocated nor leaked, so the result is well-defined.
This patch also makes a small optimization for std::deque move
assignment, to use the efficient move when is_always_equal is false, but
the allocators compare equal at runtime.
Finally, we need to remove all the Debug Mode checks which abort the
program when a self-move is detected, because it's not undefined to do
that.
Before PR 85828 can be closed we should also look into fixing
std::shuffle so it doesn't do any redundant self-swaps.
libstdc++-v3/ChangeLog:
PR libstdc++/85828
* include/bits/basic_string.h (operator=(basic_string&&)): Check
for self-move before copying with char_traits::copy.
* include/bits/hashtable.h (operator=(_Hashtable&&)): Check for
self-move.
* include/bits/stl_deque.h (_M_move_assign1(deque&&, false_type)):
Check for equal allocators.
* include/bits/stl_list.h (_M_move_assign(list&&, true_type)):
Call clear() instead of _M_clear().
* include/debug/formatter.h (__msg_self_move_assign): Change
comment.
* include/debug/macros.h (__glibcxx_check_self_move_assign):
(_GLIBCXX_DEBUG_VERIFY): Remove.
* include/debug/safe_container.h (operator=(_Safe_container&&)):
Remove assertion check for safe move and make it well-defined.
* include/debug/safe_iterator.h (operator=(_Safe_iterator&&)):
Remove assertion check for self-move.
* include/debug/safe_local_iterator.h
(operator=(_Safe_local_iterator&&)): Likewise.
* testsuite/21_strings/basic_string/cons/char/self_move.cc: New test.
* testsuite/23_containers/deque/cons/self_move.cc: New test.
* testsuite/23_containers/forward_list/cons/self_move.cc: New test.
* testsuite/23_containers/list/cons/self_move.cc: New test.
* testsuite/23_containers/set/cons/self_move.cc: New test.
* testsuite/23_containers/unordered_set/cons/self_move.cc: New test.
* testsuite/23_containers/vector/cons/self_move.cc: New test.
PR libstdc++/56267
* include/bits/hashtable_policy.h (_Hash_code_base<... false>): Grant
friendship to _Local_iterator_base<..., false>.
(_Local_iterator_base): Give protected access to all existing members.
(_Local_iterator_base::_M_curr()): New public accessor.
(_Local_iterator_base::_M_get_bucket()): New public accessor.
(_Local_iterator_base<..., false>::_M_init()): New function to manage
the lifetime of the _Hash_code_base explicitly.
(_Local_iterator_base<..., false>::_M_destroy()): Likewise.
(_Local_iterator_base<..., false>): Define copy constructor and copy
assignment operator that use new functions to manage _Hash_code_base.
(operator==(const _Local_iterator_base&, const _Local_iterator_base&),
operator==(const _Local_iterator_base&, const _Local_iterator_base&)):
Use public API for _Local_iterator_base.
* include/debug/safe_local_iterator.h (_Safe_local_iterator): Likewise.
* include/debug/unordered_map (__debug::unordered_map::erase(),
__debug::unordered_multimap::erase()): Likewise.
* include/debug/unordered_set (__debug::unordered_set::erase(),
__debug::unordered_multiset::erase()): Likewise.
* testsuite/23_containers/unordered_set/56267-2.cc: New test.
From-SVN: r206834
2013-11-08 François Dumont <fdumont@gcc.gnu.org>
* include/debug/safe_iterator.h (_BeforeBeginHelper<>::_S_Is):
Take only a const safe iterator reference.
(_BeforeBeginHelper<>::_S_Is_beginnest): Likewise.
(__get_distance): Take only one type of iterator.
(_Safe_iterator<>::_M_valid_range<>): Not template anymore.
(_Safe_iterator<>::_M_get_sequence()): Return pointer to const
sequence from a const_iterator and a pointer to sequence from an
iterator.
* include/debug/safe_iterator.tcc: Adapt.
* include/debug/safe_local_iterator.h
(_Safe_local_iterator<>::_M_valid_range<>): Not template anymore.
(_Safe_local_iterator<>::_M_get_sequence()): Return pointer to
const sequence from a const_iterator and a pointer to sequence
from an iterator.
* include/debug/safe_local_iterator.tcc: Adapt.
* include/debug/forward_list
(_BeforeBeginHelper<std::__debug::forward_list<>>): Adapt.
From-SVN: r204598
2011-07-19 François Dumont <francois.cppdevs@free.fr>
* include/debug/safe_unordered_base.h, safe_unordered_sequence.h,
safe_unordered_sequence.tcc, safe_local_iterator.h,
safe_local_iterator.tcc: New, support for unordered sequence safe
local iterators.
* include/Makefile.am: Add previous files.
* include/Makefile.in: Regenerate.
* include/debug/unordered_map, unordered_set: Implement
_Safe_unordered_sequence and expose _Safe_local_iterator.
* include/debug/safe_iterator.h, safe_iterator.tcc: Refactor
_Safe_iterator::_M_get_distance static method to expose it as
__get_distance function and use it in _Safe_local_iterator type.
* include/debug/formatter.h: Add __msg_local_iter_compare_bad
_Debug_msg_id enum entry to notify invalid comparison between local
iterators from different buckets. Add _Parameter constructor from
_Safe_local_iterator.
* include/debug/functions.h: Add __valid_range overload for
_Safe_local_iterator.
* src/debug.cc: Add _Safe_unordered_sequence_base and
_Safe_local_iterator_base methods implementations.
* config/abi/pre/gnu.ver: Add export of some
_Safe_unordered_sequence_base and _Safe_local_iterator_base methods.
* testsuite/util/debug/checks.h: Add use_invalid_iterator function to
simulate use of a singular iterator.
* testsuite/util/debug/unordered_checks.h: New, several functions
to simulate classic invalid usage of unordered sequence local
iterators.
* testsuite/23_containers/unordered_map/debug/
use_erased_local_iterator_neg.cc, invalid_local_iterator_range_neg.cc,
use_invalid_local_iterator_neg.cc, use_invalid_iterator_neg.cc,
invalid_local_iterator_compare_neg.cc: New.
* testsuite/23_containers/unordered_multimap/debug/
use_erased_local_iterator_neg.cc, invalid_local_iterator_range_neg.cc,
use_invalid_local_iterator_neg.cc, use_invalid_iterator_neg.cc,
invalid_local_iterator_compare_neg.cc: New.
* testsuite/23_containers/unordered_set/debug/
use_erased_local_iterator_neg.cc, invalid_local_iterator_range_neg.cc,
use_invalid_local_iterator_neg.cc, use_invalid_iterator_neg.cc,
invalid_local_iterator_compare_neg.cc: New.
* testsuite/23_containers/unordered_multiset/debug/
use_erased_local_iterator_neg.cc, invalid_local_iterator_range_neg.cc,
use_invalid_local_iterator_neg.cc, use_invalid_iterator_neg.cc,
invalid_local_iterator_compare_neg.cc: New.
From-SVN: r176487
Jakub Jelinek