Lemma semax_func_cons_ext_vacuous: forall {Espec: OracleKind} (V : varspecs) (G : funspecs) (C : compspecs) (fs : list (ident * Clight.fundef)) (id : ident) (ef : external_function) (argsig : typelist) (retsig : type) (G' : funspecs) cc, (id_in_list id (map fst fs)) = false -> ef_sig ef = {| sig_args := typlist_of_typelist (type_of_params (arglist 1 argsig)); sig_res := opttyp_of_type retsig; sig_cc := cc_of_fundef (External ef argsig retsig cc) |} -> semax_func V G fs G' -> semax_func V G ((id, External ef argsig retsig cc) :: fs) ((id, vacuous_funspec (External ef argsig retsig cc)) :: G').