Remark type_expect_incr:
  forall e ty1 ty2 e' te, type_expect e ty1 ty2 = OK e' -> S.satisf te e' -> S.satisf te e.

Lemma type_ros_complete: forall te ros e, S.satisf te e -> match ros with inl r => te r = Tptr | inr s => True end -> exists e', type_ros e ros = OK e' /\ S.satisf te e'.