[SciPy-dev] More bugs fixed

[Travis Oliphant]

This is just to let people know that I found and fixed the problem that 
was causing segfaults in vectorize.

Basically, when I added the new feature to allow user-defined UFUNCS to 
be created, I did not set the needed (userloops) item to NULL in the 
ufunc_frompyfunc function (I didn't initialize it at all).  Thus,  when 
the ufunc was deallocated and the XDECREF encountered, some random 
segment of memory was being DECREFd.

So, again, strange problems caused by unitialized memory being 
XDECREF'd.  Same problem, different reason.

So at least for know, my understanding of reference counting is not at 
fault :-)

I also decided to add a check for object looping and act accordingly on 
threaded machines and re-enabled the thread support for the ufunc 
loops.  This seemed to work on one multiprocessor machine I have access to.

-Travis