[Bug libstdc++/125890] allocator_traits<polymorphic_allocator> doesn't provide allocate_at_least in 16.1

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125890

--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-16 branch has been updated by Nathan Myers <ncm@gcc.gnu.org>:

https://gcc.gnu.org/g:b99c6da50262bb8e2f45c7e8f4b9d15ad29eb7d8

commit r16-9156-gb99c6da50262bb8e2f45c7e8f4b9d15ad29eb7d8
Author: Nathan Myers <ncm@cantrip.org>
Date:   Mon Jun 22 18:36:12 2026 -0400

    libstdc++: allocator traits on pmr gets allocate_at_least (P0401)
[PR125890]

    GCC 16.1's explicit specialization of std::allocator_traits on
    std::pmr::polymorphic_allocator<T> lacks the required
    definition of allocate_at_least. This patch provides it, and
    tests for its presence in C++23 and up.

    (Partly cherry-picked from r17-603-gacfdad706.)

    libstdc++-v3/Changelog:
            PR libstdc++/125890
            * include/bits/memory_resource.h (allocate_at_least): Add to
            allocator_traits<pmr::polymorphic_allocator> specialization.
            * testsuite/20_util/polymorphic_allocator/at_least.cc: New test.

    Reviewed-by: Jonathan Wakely <jwakely@redhat.com>