$ git clone -n https://src.fedoraproject.org/rpms/ocaml-perl4caml.git /var/lib/mock/f40-build-783994-133236/root/chroot_tmpdir/scmroot/ocaml-perl4caml
Cloning into '/var/lib/mock/f40-build-783994-133236/root/chroot_tmpdir/scmroot/ocaml-perl4caml'...
$ git fetch origin bc08ae6cc37cb0a902abb051a150c42f204033e2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ocaml-perl4caml
 * [new ref]         bc08ae6cc37cb0a902abb051a150c42f204033e2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bc08ae6 Upstream patch to fix some build failures (RHBZ#2261832)