Section SOUNDNESS_CONSTRUCTORS.
Variable ce: composite_env.
Variable e: typenv.
Variable rt: type.
Hint Resolve check_rval_wt check_lval_wt: ty.
Hint Extern 1 (wt_expr _ _ _) => (unfold wt_expr; simpl): ty.
End SOUNDNESS_CONSTRUCTORS.

Lemma retype_function_sound:
forall ce e f f', retype_function ce e f = OK f' -> wt_function ce e f'.