$ git clone -n https://src.fedoraproject.org/rpms/xorg-x11-xdm.git /var/lib/mock/f29-build-4507-1054/root/thebuilddir/tmp/scmroot/xorg-x11-xdm
Cloning into '/var/lib/mock/f29-build-4507-1054/root/thebuilddir/tmp/scmroot/xorg-x11-xdm'...
$ git reset --hard 2320350210290afc8c61e31b3273bd6601da3ee3
HEAD is now at 2320350 - Rebuilt for https://fedoraproject.org/wiki/Fedora_28_Mass_Rebuild