End SepAlloc.
Section SepBlockAlloc.
Variables (A : Type) (v : A) (n : nat).
Definition allocb_s : spec ptr :=
(emp, fun y i m => exists x:ptr, y = Val x /\ m = updi x (nseq n v)).

Lemma allocbP : Model.conseq (Model.allocb_s v n) [allocb_s].
Definition allocb : STsep allocb_s := Model.Do (Model.allocb v n) allocbP.