$ git clone -n https://src.fedoraproject.org/rpms/ocaml-ctypes.git /var/lib/mock/f39-build-2473242-61515/root/chroot_tmpdir/scmroot/ocaml-ctypes
Cloning into '/var/lib/mock/f39-build-2473242-61515/root/chroot_tmpdir/scmroot/ocaml-ctypes'...
$ git fetch origin bac7e774c2470b32d83dcdea2e863f8850f0676e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ocaml-ctypes
 * [new ref]         bac7e774c2470b32d83dcdea2e863f8850f0676e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bac7e77 Rebuild for changed ocamlx(Toploop) hash