(* to make the proof faster, we avoid unfolding of those definitions *)
Definition Jspec'_juicy_mem_equiv_def CS ext_link :=
  ext_spec_stable juicy_mem_equiv (JE_spec _ ( @OK_spec (Concurrent_Espec unit CS ext_link))).Definition Jspec'_hered_def CS ext_link :=
   ext_spec_stable age (JE_spec _ ( @OK_spec (Concurrent_Espec unit CS ext_link))).

Lemma shape_of_args2 (F V : Type) (args : list val) v (ge : Genv.t F V) : Val.has_type_list args (sig_args (ef_sig CREATE)) -> v <> Vundef -> v = eval_id _args (make_ext_args (filter_genv (symb2genv (genv_symb_injective ge))) (_f :: _args :: nil) args) -> exists arg1, args = arg1 :: v :: nil.