Hey,

On Friday, December 31, 2004, at 02:35 PM, Nuno Teixeira wrote:
> I read a lot of opinions between -O and -O2 and for what I read it
> does't make any binary performance diference, it takes more compile time
> only.
>
this is plainly wrong. O2 is often better than O. Rare circumstances are 
where you can have cache size problems for example or compiler bugs or 
particularly difficult code. It is often that O3 doesn't give much 
improved results, but that isn't true in general either. Os can be 
interesting too.

I find O2 a good "generic choice". Changes and improvements should be 
made from program to program after some benchmarks on different hosts.

-R