[Bug c++/93958] gcc trunk supports -std=c++20 but not -std=gnu++20

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93958

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Marek Polacek <mpolacek@gcc.gnu.org>:

https://gcc.gnu.org/g:e78e50d57edf4e0e49576a7a31b01477eed08223

commit r10-6977-ge78e50d57edf4e0e49576a7a31b01477eed08223
Author: Marek Polacek <polacek@redhat.com>
Date:   Sat Feb 29 14:50:19 2020 -0500

    c++: Add -std=gnu++20 option [PR93958]

    One missing bit from r10-6656.  The docs and target-supports.exp
    already handle -std=gnu++20.

    2020-03-02  Marek Polacek  <polacek@redhat.com>

        PR c++/93958 - add missing -std=gnu++20.
        * c.opt: Add -std=gnu++20.