$ git clone -n https://src.fedoraproject.org/rpms/llvm6.0.git /var/lib/mock/f31-build-90584-32231/root/chroot_tmpdir/scmroot/llvm6.0
Cloning into '/var/lib/mock/f31-build-90584-32231/root/chroot_tmpdir/scmroot/llvm6.0'...
$ git reset --hard 57bde13a9f303cc556efe26cffdb08d1b9316dc7
HEAD is now at 57bde13 - Rebuilt for https://fedoraproject.org/wiki/Fedora_31_Mass_Rebuild