Definition removeUndefs (j l j':meminj):meminj :=
fun b => match j b with
None => match l b with
None => None | Some (b1,delta1) => j' b
end
| Some(b2,delta2) => Some(b2, delta2)
end.

Lemma meminj_no_overlap_inject_incr:
forall j m (NOV: Mem.meminj_no_overlap j m) k (K:inject_incr k j),
Mem.meminj_no_overlap k m.