[Bug c++/78301] noexcept() operator rejects sibling method call without object

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78301

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
N.B. it's easy to workaround the bug by using this->inner()

Possibly related to PR 66256