Module MemoryWD.
(** Valid memories are the ones that do not contain any dangling pointers*)
Definition valid_mem m :=
forall b,
Mem.valid_block m b ->
forall ofs mv,
Maps.ZMap.get ofs (Mem.mem_contents m) # b = mv ->
match mv with
| Fragment v q n =>
mem_wd.val_valid v m
| _ => True
end.

Lemma getN_wd :
forall (f : memren) (m : mem) b,
Mem.valid_block m b ->
valid_mem m ->
domain_memren f m ->
forall (n : nat) (ofs : Z),
valid_memval_list f (Mem.getN n ofs (Mem.mem_contents m) # b).