This is an interesting package, and I found this interesting post concerning it:
ten years of free software -- part 8 (pentium-builder)
I'm trying it out now with libxml2, but I'm already noticing this:
`-mcpu=' is deprecated. Use `-mtune=' or '-march=' instead.
I just edited /usr/bin/gcc and g++ to comment out -march. This is a very cool package. I hope it gets updated, maybe I'll take a look at updating it.