https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57582
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- N.B. using `class clone*` to refer to the type works. This is the same as needing to use `struct stat` to disambiguate the type from the function. If we stop defining _GNU_SOURCE that workaround wouldn't be needed.
