https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57272
--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:2ce99c0088ed97991f61cbdefa83f682c2ef4364 commit r15-6272-g2ce99c0088ed97991f61cbdefa83f682c2ef4364 Author: Jonathan Wakely <jwak...@redhat.com> Date: Sun Dec 8 14:34:01 2024 +0000 libstdc++: Fix fancy pointer support in linked lists [PR57272] The union members I used in the new _Node types for fancy pointers only work for value types that are trivially default constructible. This change replaces the anonymous union with a named union so it can be given a default constructor and destructor, to leave the variant member uninitialized. This also fixes the incorrect macro names in the alloc_ptr_ignored.cc tests as pointed out by François, and fixes some std::list pointer confusions that the fixed alloc_ptr_ignored.cc test revealed. libstdc++-v3/ChangeLog: PR libstdc++/57272 * include/bits/forward_list.h (__fwd_list::_Node): Add user-provided special member functions to union. * include/bits/stl_list.h (__list::_Node): Likewise. (_Node_base::_M_hook, _Node_base::swap): Use _M_base() instead of std::pointer_traits::pointer_to. (_Node_base::_M_transfer): Likewise. Add noexcept. (_List_base::_M_put_node): Use 'if constexpr' to avoid using pointer_traits::pointer_to when not necessary. (_List_base::_M_destroy_node): Fix parameter to be the pointer type used internally, not the allocator's pointer. (list::_M_create_node): Likewise. * testsuite/23_containers/forward_list/requirements/explicit_instantiation/alloc_ptr.cc: Check explicit instantiation of non-trivial value type. * testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr.cc: Likewise. * testsuite/23_containers/forward_list/requirements/explicit_instantiation/alloc_ptr_ignored.cc: Fix macro name. * testsuite/23_containers/list/requirements/explicit_instantiation/alloc_ptr_ignored.cc: Likewise.
