$ git clone -n https://src.fedoraproject.org/rpms/glib.git /var/lib/mock/f40-build-2218098-52588/root/chroot_tmpdir/scmroot/glib
Cloning into '/var/lib/mock/f40-build-2218098-52588/root/chroot_tmpdir/scmroot/glib'...
$ git fetch origin c37bef117f25ec7eb7d7588a37406e0235707d8b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/glib
 * [new ref]         c37bef117f25ec7eb7d7588a37406e0235707d8b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c37bef1 Set build_type_safety_c to 0 (#2167383)