$ git clone -n https://gitee.com/opencloudos-stream/llvm.git /var/lib/mock/dist-ocs23-base-build-370232-45887/root/chroot_tmpdir/scmroot/llvm
Cloning into '/var/lib/mock/dist-ocs23-base-build-370232-45887/root/chroot_tmpdir/scmroot/llvm'...
$ git fetch origin master:KOJI_FETCH_HEAD
From https://gitee.com/opencloudos-stream/llvm
 * [new branch]      master     -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 21256d3 !23 Enable -fasynchronous-unwind-tables by default on Linux Merge pull request !23 from dpdwaj/master