> Well, you're going to have to ask a numerical analyst about this. If you
> take that stance then -ffast-math is always wrong, no matter what the
> combination of other switches. The "wrong" results might be harder to
> reproduce without any optimization going on, but they could still happen.
Grumble. OK, I'll rephrase my statement: it is not "wrong", but "does
not produce the *required* result".
The date/time stuff relies on conventional IEEE arithmetic rounding and
truncation rules to produce the world-wide, universally accepted
conventions for date/time representation. And will do so *if* the
compiler produces math which conforms to IEEE (and many other, in my
experience) conventions for arithmetic. So, if someone actually would
want to get date/time results which conform to those conventions, and if
they would characterize that conformance as "correct", then they might
make the leap of phrase to characterize nonconformance to those
conventions as "wrong".
- Thomas (who is just finishing eight days of jury
duty ;)