Variable Espec : OracleKind.

(* Lemmas [semax_ext'_void] and [semax_ext_void] were needed before we used optyp_of_type of funsig2signature, we should be able to get rid of them now *)
Lemma semax_ext'_void (ext_link: Strings.String.string -> ident) id sig cc A P Q NEP NEQ (fs : funspecs) :
let f := mk_funspec (sig, tvoid) cc A P Q NEP NEQ in
In (ext_link  id,f) fs ->
funspecs_norepeat fs ->
(forall n, semax_external (add_funspecs Espec ext_link fs) (fst (split sig))
(EF_external id (mksignature (map typ_of_type (map snd sig)) None cc)) _ P Q n).