Abort.  (* not likely true *)

(* Specifications: *)
Lemma lseg_local_facts:
forall ls dsh psh contents p q,
lseg ls dsh psh contents p q |--
!! (is_pointer_or_null p /\ (p=q <-> contents=nil)).
Lemma lseg_local_facts:
forall ls sh contents p q,
lseg ls sh contents p q |--
!! (is_pointer_or_null p /\ (p=q <-> contents=nil)).
Lemma lseg_local_facts:
forall ls dsh psh contents p q,
lseg ls dsh psh contents p q |--
!! (is_pointer_or_null p /\ (p=q <-> contents=nil)).