$ git clone -n https://src.fedoraproject.org/rpms/rust-cc.git /var/lib/mock/f38-build-side-42-init-devel-1395414-31050/root/chroot_tmpdir/scmroot/rust-cc
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1395414-31050/root/chroot_tmpdir/scmroot/rust-cc'...
$ git fetch origin 864192baeb4b77c3697173f831cff0efdd2d6f98:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-cc
 * [new ref]         864192baeb4b77c3697173f831cff0efdd2d6f98 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 864192b Update to version 1.0.83; Fixes RHBZ#2229571