By default zfs builds with its ASSERT()s disabled. Passing the --enable-debug option at ./configure time enables them plus some additional sanity checks. We should make this the default for Maloo to ensure bugs are caught immediately. However, before we can do that it looks like we have several existing issue which are going to need to be fixed. I've filed the first ASSERT as ORI-540 I expect there will be a few more filed shortly.