https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122418
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- [func.require] p1 seems clear that INVOKE should use reference_wrapper::get(). Nobody cares about volatile call wrappers. Even perfect forwarding call wrappers don't care about volatile, see [func.require] p4: "where cv represents the cv-qualifiers of the call wrapper and where cv shall be neither volatile nor const volatile."
