[Bug libstdc++/90943] Visiting inherited variants no longer works in 9.1

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90943

--- Comment #11 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Jonathan Wakely
<r...@gcc.gnu.org>:

https://gcc.gnu.org/g:90b94ca5a2ddd7834afff9ad5e1afff5554e0752

commit r11-9831-g90b94ca5a2ddd7834afff9ad5e1afff5554e0752
Author: Jonathan Wakely <jwak...@redhat.com>
Date:   Mon Apr 19 14:49:12 2021 +0100

    libstdc++: Allow visiting inherited variants [PR 90943]

    Implement the changes from P2162R2 (as a DR for C++17).

    Signed-off-by: Jonathan Wakely <jwak...@redhat.com>

    libstdc++-v3/ChangeLog:

            PR libstdc++/90943
            * include/std/variant (__cpp_lib_variant): Update value.
            (__detail::__variant::__as): New helpers implementing the
            as-variant exposition-only function templates.
            (visit, visit<R>): Use __as to upcast the variant parameters.
            * include/std/version (__cpp_lib_variant): Update value.
            * testsuite/20_util/variant/visit_inherited.cc: New test.

    (cherry picked from commit c46ecb0112e91c80ee111439e79a58a953e4479d)