$ git clone -n https://src.fedoraproject.org/rpms/mathgl.git /var/lib/mock/f42-build-864762-172559/root/chroot_tmpdir/scmroot/mathgl
Cloning into '/var/lib/mock/f42-build-864762-172559/root/chroot_tmpdir/scmroot/mathgl'...
$ git fetch origin 1cfc0b79a143512fe69dbcc115735bea6fa47ea3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mathgl
 * [new ref]         1cfc0b79a143512fe69dbcc115735bea6fa47ea3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1cfc0b7 Rebuild for octave 9.2