Nicolas Calimet <pov### [at] freefr> wrote:
> > > But once I have a little breathing room, I'll
> > rebuild using icc and -O3 and see what happens.
>
>  It could make your binary somewhat faster, since the default icc
> optimization level seems -O2 (in fact -O but the icc help page says that
> -O2 and -O1/-O are equivalent).  Probably not so critical either.
>
>

I am actually a bit weary of compiler optimizations on graphics code.
They've burned me before. On two separate projects, using ms dev studio
vc++, my work was derailed by optimizations. In both cases, it was rotation
operations. The rotations worked just fine on my machine, so I passed my
code onto QA and/or the customer, only to have them report very
embarrassing bugs of those rotations doing utterly ludicrous things (making
me look like an idiot for turning in code like that). ie, it worked fine on
my graphics card, but was a mess on their graphics card.  So I rebuilt the
code turning off compiler optimizations, and it worked as intended on all
graphics cards.

Things like that annoy me to no end. How could a compiler impart
optimizations without ensuring the coded computation is not undermined?
Yet its hard to blame the compiler when it worked on SOME graphics
hardware, but clearly the optimizations were at least a party to the crime.

But I'm drifting off topic...

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