$ git clone -n https://gitee.com/idolsama/clang.git /var/lib/mock/dist-an23-build-337376-69705/root/chroot_tmpdir/scmroot/clang
Cloning into '/var/lib/mock/dist-an23-build-337376-69705/root/chroot_tmpdir/scmroot/clang'...
$ git fetch origin 4df823bb4af2136fde35103aa942fb903ba88eaf:KOJI_FETCH_HEAD
From https://gitee.com/idolsama/clang
 * [new ref]         4df823bb4af2136fde35103aa942fb903ba88eaf -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4df823b add riscv64 support