$ git clone -n https://src.fedoraproject.org/rpms/gazebo.git /var/lib/mock/f42-build-863021-171338/root/chroot_tmpdir/scmroot/gazebo
Cloning into '/var/lib/mock/f42-build-863021-171338/root/chroot_tmpdir/scmroot/gazebo'...
$ git fetch origin d356f0a37b294b15a9f253b102885e0cbae30275:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gazebo
 * [new ref]         d356f0a37b294b15a9f253b102885e0cbae30275 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d356f0a rebuild for tinyxml2