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Re: Optimisation prevents overflow?
Brooks Moses wrote:
> Paul Brook has corrected me. The extra-precision registers _do_ have
> enough extra precision that 273 is a reasonable answer for this theory.
>
> Sorry for the confusion, then. :)
>
> So, yeah, -ffloat-store or -mfpmath=sse is the right answer.
This brings me to a "philosophical" question, then. Say that program
"foo" gives different results depending on the use of -ffloat-store; I
am not talking about round-off here, I mean real differences. Would you
say that "foo" is not portable? In other words, relying on overflow (or
underflow) is obviously not portable, but is overflow the _only_ way to
trigger inconsistent behaviours?
Davide