(* No unvalid pointers, i.e. othing pointing after nextblock *)
Definition mem_wd (m:mem):=
inject_neutral (nextblock m) m.
(* All arguments are in memory and without unvalid pointers*)
Definition arg_well_formed args m0:=
Val.inject_list (flat_inj (nextblock m0)) args args.
Remark mem_wd_inject:
forall m, mem_wd m -> inject (flat_inj (nextblock m)) m m.

Theorem alloc_inject_neutral:
forall thr m lo hi b m',
alloc m lo hi = (m', b) ->
inject_neutral thr m ->
Plt (nextblock m) thr ->
inject_neutral thr m'.