+ intros. xomega.
+ induction 1.
- apply Mem.nextblock_storebytes in H;
rewrite H; xomega.
- apply Mem.nextblock_alloc in H.
rewrite H. clear. xomega.
- apply nextblock_freelist in H.
rewrite H; xomega.
- xomega.
Qed.

Lemma alloc_inc_perm: forall m lo hi m' b
(M: Mem.alloc m lo hi = (m',b)) m1 (PLE: perm_lesseq m m1),
exists m1' : mem, Mem.alloc m1 lo hi =(m1',b) /\ perm_lesseq m' m1'.