Works pretty well for me on my MacBook Pro, but on my G5 it performed
abysmally. In fact, it ran so much worse that I cleaned up my sandbox
and did both checks all over again to make sure I didn't mess something
up. It looks like my MacBook Pro saw about a 7% improvement while my
G5 saw a 14% degradation. Both computers are running Mac OS X 10.5.6
with the latest Xcode - 3.1.2. On both computers gcc -v reports 4.0.1,
Apple build 5490.
If this is applied to the core I think it will have to select for more
than just gcc. It will also have to select based on the instruction set
architecture.