On Wed, 14 May 2025 at 17:31, François Dumont <frs.dum...@gmail.com> wrote: > > On 12/05/2025 23:03, Jonathan Wakely wrote: > > On 31/03/25 22:20 +0200, François Dumont wrote: > >> Hi > >> > >> Following this previous patch > >> https://gcc.gnu.org/pipermail/libstdc++/2024-August/059418.html I've > >> completed it for the _Safe_unordered_container_base type and > >> implemented the rest of the change to store the safe iterator > >> sequence as a pointer-to-const. > >> > >> libstdc++: Make debug iterator pointer sequence const [PR116369] > >> > >> In revision a35dd276cbf6236e08bcf6e56e62c2be41cf6e3c 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. > >> Symbols export are maintained thanks to __asm directives. > >> > > I can't compile this, it seems to be missing changes to > > safe_local_iterator.tcc: > > > > In file included from > > /home/jwakely/src/gcc/build/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/safe_local_iterator.h:444, > > from > > /home/jwakely/src/gcc/gcc/libstdc++-v3/src/c++11/debug.cc:33: > > /home/jwakely/src/gcc/build/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/safe_local_iterator.tcc: > > In member function ‘typename > > __gnu_debug::_Distance_traits<_Iterator>::__type > > __gnu_debug::_Safe_local_iterator<_Iterator, > > _Sequence>::_M_get_distance_to(const > > __gnu_debug::_Safe_local_iterator<_Iterator, _Sequence>&) const’: > > /home/jwakely/src/gcc/build/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/safe_local_iterator.tcc:47:17: > > error: there are no arguments to ‘_M_get_sequence’ that depend on a > > template parameter, so a declaration of ‘_M_get_sequence’ must be > > available [-Wtemplate-body] > > 47 | _M_get_sequence()->bucket_size(bucket()), > > | ^~~~~~~~~~~~~~~ > > /home/jwakely/src/gcc/build/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/safe_local_iterator.tcc:47:17: > > note: (if you use ‘-fpermissive’, G++ will accept your code, but > > allowing the use of an undeclared name is deprecated) > > /home/jwakely/src/gcc/build/x86_64-pc-linux-gnu/libstdc++-v3/include/debug/safe_local_iterator.tcc:59:18: > > error: there are no arguments to ‘_M_get_sequence’ that depend on a > > template parameter, so a declaration of ‘_M_get_sequence’ must be > > available [-Wtemplate-body] > > 59 | -_M_get_sequence()->bucket_size(bucket()), > > | ^~~~~~~~~~~~~~~ > > > Yes, sorry, I had already spotted this problem, but only updated the PR > and not re-sending patch here. > > > > > >> Also available as a PR > >> > >> https://forge.sourceware.org/gcc/gcc-TEST/pulls/47 > >> > >> /** Detach all singular iterators. > >> * @post for all iterators i attached to this sequence, > >> * i->_M_version == _M_version. > >> */ > >> void > >> - _M_detach_singular(); > >> + _M_detach_singular() const > >> + __asm("_ZN11__gnu_debug19_Safe_sequence_base18_M_detach_singularEv"); > > > > Does this work on all targets? > > No idea ! I thought the symbol name used here just had to match the > entries in config/abi/pre/gnu.ver.
That linker script is not used for all targets. > > It is what other usages of __asm in the lib are doing for the moment, in > <format> header, wo target considerations. The _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT macro is only ever defined for powerpc64le-unknown-linux-gnu so those uses in <format> are certainly not without target considerations. They are used on exactly one particular target, and no others. > > > > I think darwin uses __Z as the prefix > > for mangled names. > > It might be necessary to use a macro to do this, so that it > > conditionally puts "_" before the name. > > > If it's the only "exotic" target I can indeed deal with it with a macro. > Otherwise I might have to find another alternative. > > Here is an updated version considering all your other remarks. > > libstdc++: Make debug iterator pointer sequence const [PR116369] > > In revision a35dd276cbf6236e08bcf6e56e62c2be41cf6e3c 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. > Symbols export are maintained thanks to __asm directives. > > libstdc++-v3/ChangeLog: > > PR c++/116369 > * include/debug/safe_base.h > (_Safe_iterator_base::_M_sequence): Declare as > pointer-to-const. > (_Safe_iterator_base::_M_attach, _M_attach_single): Take > pointer-to-const > _Safe_sequence_base. Add __asm directive to preserve name > mangling. > (_Safe_sequence_base::_M_detach_all, _M_detach_singular, > _M_revalidate_singular) > (_M_swap, _M_get_mutex, _M_attach, _M_attach_single, > _M_detash, _M_detash_single): > Add const qualifier and __asm directive to preserve name > mangling. > * 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): Take > _Safe_unordered_container_base as pointer-to-const. Add > __asm directive to preserve > name mangling. > (_Safe_unordered_container_base::_M_local_iterators, > _M_const_local_iterators): > Add mutable. > (_Safe_unordered_container_base::_M_detach_all, _M_swap, > _M_attach_local) > (_M_attach_local_single, _M_detach_local, > _M_detach_local_single): Add const > qualifier and __asm directive to preserve name mangling. > * 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. > * include/debug/safe_local_iterator.tcc: Adapt. > * include/debug/formatter.h: Adapt. > * include/debug/safe_sequence.h > (_Safe_sequence<>::_M_invalidate_if, _M_transfer_from_if): > Add const qualifier. > * include/debug/safe_sequence.tcc: Adapt. > * 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. > > François >
