$ git clone -n https://src.fedoraproject.org/rpms/ghc-math-functions.git /var/lib/mock/f41-build-side-1-2636925-26276/root/chroot_tmpdir/scmroot/ghc-math-functions
Cloning into '/var/lib/mock/f41-build-side-1-2636925-26276/root/chroot_tmpdir/scmroot/ghc-math-functions'...
$ git fetch origin 66b401a2695624a07ddb79f1ea75ad6eab454edb:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-math-functions
 * [new ref]         66b401a2695624a07ddb79f1ea75ad6eab454edb -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 66b401a https://hackage.haskell.org/package/math-functions-0.3.4.4/changelog