$ git clone -n https://src.fedoraproject.org/rpms/ghc-deriving-compat.git /var/lib/mock/f41-build-839411-160145/root/chroot_tmpdir/scmroot/ghc-deriving-compat
Cloning into '/var/lib/mock/f41-build-839411-160145/root/chroot_tmpdir/scmroot/ghc-deriving-compat'...
$ git fetch origin 7ef35a8f332656eb811d51ea3ad746ce6f05a925:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-deriving-compat
 * [new ref]         7ef35a8f332656eb811d51ea3ad746ce6f05a925 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7ef35a8 https://hackage.haskell.org/package/deriving-compat-0.6.6/changelog