$ git clone -n https://src.fedoraproject.org/rpms/ghc-language-c.git /var/lib/mock/f40-build-2185149-51289/root/chroot_tmpdir/scmroot/ghc-language-c
Cloning into '/var/lib/mock/f40-build-2185149-51289/root/chroot_tmpdir/scmroot/ghc-language-c'...
$ git fetch origin c42ac9edf539b7b979df4c4c6a09f787050c2aa8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-language-c
 * [new ref]         c42ac9edf539b7b979df4c4c6a09f787050c2aa8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c42ac9e bump release