Please add FreeBSD to the list of OS's you use for testing of compilation.
You have no idea how frustrating it is to have an open source project claim to run on unix like operating systems and not compile correctly on FreeBSD or Mac OS X...
As much as I agree... I'm not sure how much it's worth the effort until someone points out that your project definitely doesn't work. Even looking at silly stats like: http://distrowatch.com/stats.php?section=popularity - covering one popular rpm and one deb distribution, you're covering majority already (with only slight modifications if necessary). Mac users will expect their own packages anyways and you can't run Mac OSX legally without owning the hardware, which many developers don't own.
Regarding FreeBSD... lack of any good result in the first 3 pages of "freebsd packaging guide" search should explain a lot.
Generally if it compiles on FreeBSD it compiles on Mac OS X, at least that has been my experience in the past. I am in the unique position that I develop on Mac OS X, then do my tests on FreeBSD and when it works on those attempt it on Linux.
The counter-argument is that testing on more platforms tends to expose bugs that it's worth fixing because they would have affected you anyway, you just didn't know it yet.
Ok - I wasn't clear on that one. I know they're called ports and would probably look for stuff like port creation / porting / port-something-else. Yet, it seems a bit weird to me that looking for freebsd packaging guide doesn't give you anything even remotely useful. (consider some developer who has a couple hours to spend, thinks about making a freebsd port, looks for packaging information and concludes that it's not even documented / not worth learning right now)
You have no idea how frustrating it is to have an open source project claim to run on unix like operating systems and not compile correctly on FreeBSD or Mac OS X...