(*map typeof bl = map (@snd _ _) (fst fsig) ->*)
(*    Forall (fun it => complete_type (composite_types Delta) (snd it) = true) (fn_vars (snd fsig)) ->*)
(*filter_genv psi = ge_of rho ->*)

Lemma func_at_func_at':
forall fs loc, func_at fs loc |-- func_at' fs loc.