Why does OSX Snow Leopard ship with GCC 4.2.1, and is it possible (advisable?) to upgrade? [closed]

Question

Maybe they have a good reason, but I'm struggling to understand why a new OS would still ship with such an old compiler that was originally released in 2007. Did Apple modify it heavily and so therefore it has some features that are required? Is it possible to just download 4.5.1 and use it with XCode?

Answer 1

4.2.1 was the last gcc which was covered by version 2 of the GPL. Coincidence? I doubt it.