$ git clone -n https://gitee.com/fundawang/llvm.git /var/lib/mock/dist-an23-build-189849-60753/root/chroot_tmpdir/scmroot/llvm
Cloning into '/var/lib/mock/dist-an23-build-189849-60753/root/chroot_tmpdir/scmroot/llvm'...
$ git fetch origin 2bacfd25f6dc7ab754418cb74b5fe4518e1e3065:KOJI_FETCH_HEAD
From https://gitee.com/fundawang/llvm
 * [new ref]         2bacfd25f6dc7ab754418cb74b5fe4518e1e3065 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2bacfd2 do not depend on clang