(* uncomment for ssreflect trunk *)
Notation eqn_addl := eqn_add2l.Notation modn_addl := modnDl.Notation modn_mulr := modnMr.Notation modn_add2m := modnDm.Notation modn_addr := modnDr.(*************)
(* Locations *)
(*************)

Inductive ptr := ptr_nat of nat.(*************)
(* Locations *)
(*************)

Inductive ptr := ptr_nat of nat.Definition null := ptr_nat 0.

Lemma eq_ptrP : Equality.axiom eq_ptr.