$ git clone -n https://gitee.com/mgb01105731/libcxx.git /var/lib/mock/dist-an23-build-540511-84787/root/chroot_tmpdir/scmroot/libcxx
Cloning into '/var/lib/mock/dist-an23-build-540511-84787/root/chroot_tmpdir/scmroot/libcxx'...
$ git fetch origin 264b5663937a3a263f546058aa89df5a885123ca:KOJI_FETCH_HEAD
From https://gitee.com/mgb01105731/libcxx
 * [new ref]         264b5663937a3a263f546058aa89df5a885123ca -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 264b566 Update to 17.0.6