(** ** Lemmas about erased values*)

  Definition isDefined v :=
    match v with
    | Vundef => false
    | _ => true
    end.

Lemma val_erasure_longofsingle: forall v v' (Hval_erasure: val_erasure v v'), val_erasure (Val.maketotal (Val.longofsingle v)) (Val.maketotal (Val.longofsingle v')).