$ git clone -n https://gitee.com/renping000/llvm.git /var/lib/mock/dist-an23-build-191659-60794/root/chroot_tmpdir/scmroot/llvm
Cloning into '/var/lib/mock/dist-an23-build-191659-60794/root/chroot_tmpdir/scmroot/llvm'...
$ git fetch origin d8e31b0cb44a5620c59854da5cbd685ecd6c6020:KOJI_FETCH_HEAD
From https://gitee.com/renping000/llvm
 * [new ref]         d8e31b0cb44a5620c59854da5cbd685ecd6c6020 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d8e31b0 optimise spec file