https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95626
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution|--- |DUPLICATE
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This is not a bug, subsumption doesn't work for !B
To make it work you need to define a concept, as in your second example.
This is explained in the C++20 draft by the note in [temp.constr.op] p5, which
was added by https://wg21.link/p1971r0#US111
*** This bug has been marked as a duplicate of bug 92102 ***
