> I would be very careful using any optimization that sets the -fns on
> Sun Studio, as I've seen significant differences in results when
> enabling this. For that matter, -ffast-math has a similar effect with
> gcc.

No such optimization is involved, because no such flags are passed.
This is pure speculation on your part, since you don't know what compiler
flags i use.

> I question how much any of this would affect KDE though, since
> enhancements to both Sun Studio and GCC optimization have had to do
> additions for the new incarnations of simd instructions and should
> really only affect floating point performance, so far as I am aware.

Forget KDE. i posted yesterday the results of fibonacci, which does not,
and cannot, involve, any floating point operations. (i *hope* we're not 
going to argue this one).

There are other reasons for me stating that no floating point optimizations
are being performed. Both KDE and GNOME being mostly GUI's, most of their 
time is spent doing  integer-based operations. Which is the main reason for 
choosing fibonacci as an example, as opposed to some other silly test program 
involving floating point.

As an aside, floating point is not the only place where good compilers
can achieve  optimizations. And in this particular case, floating point
optimization is completely irrelevant.

Now. Are we going to accept that Sun Studio generates better and faster
code, as previously shown, or are we going to continue speculating
on "what could happen if what just happened did not happen, and instead,
what i would have liked to happen, happened".

--Stefan
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