(* This file is developed by Qinxiang Cao, Aquinas Hobor and Shengyi Wang in 2015. *)

Lemma range_overlap_non_zero: forall l1 n1 l2 n2, range_overlap l1 n1 l2 n2 -> n1 > 0 /\ n2 > 0.
Definition pointer_range_overlap p n p' n' :=
exists l l', val2adr p l /\ val2adr p' l' /\ range_overlap l n l' n'.