(** Preservation of [free] operations *)

Lemma free_right_inject:
forall f m1 m2 b lo hi m2',
inject f m1 m2 ->
free m2 b lo hi = Some m2' ->
(forall b1 delta ofs k p,
f b1 = Some(b, delta) -> perm m1 b1 ofs k p ->
lo <= ofs + delta < hi -> False) ->
inject f m1 m2'.