Hint Rewrite @subst_lift4 (*@subst_lift4'*) @subst_lift4C : subst.

(* Specifications: *)
Lemma bool_val_int_eq_e:
forall i j m, Cop.bool_val (Val.of_bool (Int.eq i j)) type_bool m = Some true ->
i=j.
Lemma bool_val_notbool_ptr:
forall v t m,
match t with Tpointer _ _ => True | _ => False end ->
(Cop.bool_val (force_val (Cop.sem_notbool v t m)) type_bool m = Some true)
= (v = nullval).