[Bug libstdc++/120446] [C++23] Implement P2655R3 common_reference_t of reference_wrapper Should Be a Reference Type

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120446

--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Patrick Palka <ppalka@gcc.gnu.org>:

https://gcc.gnu.org/g:d1ac432c5a889a101e5a81ec349f76e55403c2f4

commit r16-5922-gd1ac432c5a889a101e5a81ec349f76e55403c2f4
Author: Patrick Palka <ppalka@redhat.com>
Date:   Fri Dec 5 13:43:40 2025 -0500

    libstdc++: Implement rest of P2655R3 common_reference of reference_wrapper

            PR libstdc++/120446

    libstdc++-v3/ChangeLog:

            * include/bits/refwrap.h (__detail::__is_ref_wrapper):
            Define as per P2655R3 for C++20.
            (__detail::__ref_wrap_common_reference_exists_with): Likewise.
            (basic_common_reference): Define partial specializations using
            the above as per P2655R3 for C++20.
            * include/bits/version.def (common_reference_wrapper): New.
            * include/bits/version.h: Regenerate.
            * include/std/functional (__glibcxx_want_common_reference_wrapper):
            Define.
            * testsuite/20_util/reference_wrapper/p2655r3.cc: New test.

    Co-authored-by: Tomasz KamiÅski <tkaminsk@redhat.com>
    Reviewed-by: Tomasz KamiÅski <tkaminsk@redhat.com>
    Reviewed-by: Jonathan Wakely <jwakely@redhat.com>