Hint Resolve expr_closed_cast expr_closedl_cast : closed.

(* Specifications: *)
Lemma expr_closed_field: forall {cs: compspecs} S e f t,
lvalue_closed_wrt_vars S e ->
expr_closed_wrt_vars S (Efield e f t).
Lemma expr_closedl_field: forall S e f t,
lvalue_closed_wrt_lvars S e ->
expr_closed_wrt_lvars S (Efield e f t).