$ git clone -n https://gitee.com/wenyuzifang/clang.git /var/lib/mock/dist-an23-build-485092-74348/root/chroot_tmpdir/scmroot/clang
Cloning into '/var/lib/mock/dist-an23-build-485092-74348/root/chroot_tmpdir/scmroot/clang'...
$ git fetch origin 2133b74b15ca5881eae1d887a3bf1db862a3d881:KOJI_FETCH_HEAD
From https://gitee.com/wenyuzifang/clang
 * [new ref]         2133b74b15ca5881eae1d887a3bf1db862a3d881 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2133b74 Update code from upstream