Memory leaks/bugs verification

[Sad Clouds <cryintothebluesky%googlemail.com@localhost>]

Are there any frameworks used by NetBSD developers to verify that
userlevel programs are free of memory leaks? I'm thinking about
something like dmalloc, or Solaris libumem, etc.

If currently there are no such frameworks, would it be useful to have
them? Do occasional memory leaks and buffer overruns present an issue
for programs in base system, or do they not even occur?