[Bug libstdc++/78905] Add a macro to determine that the <regex> library is implemented

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78905

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |coypu at sdf dot org

--- Comment #11 from Jonathan Wakely <redi at gcc dot gnu.org> ---
*** Bug 81353 has been marked as a duplicate of this bug. ***