$ git clone -n https://src.fedoraproject.org/rpms/rust-memchr.git /var/lib/mock/f45-build-43225-801/root/chroot_tmpdir/scmroot/rust-memchr
Cloning into '/var/lib/mock/f45-build-43225-801/root/chroot_tmpdir/scmroot/rust-memchr'...
$ git fetch origin b83fd361dfbf83b8239f613de68ce47c781a9b0b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-memchr
 * [new ref]         b83fd361dfbf83b8239f613de68ce47c781a9b0b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b83fd36 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild