> Date: Mon, 18 Feb 2002 15:23:34 -0500 (EST)
> From: Stephen L Moshier <firstname.lastname@example.org>
> On Mon, 18 Feb 2002, Geoff Keating wrote:
> > ... actually, C99 seems to imply that all supported rounding
> > precisions should work for the math library
> Could you point out specifically where it says that?
It would have to specifically say that it doesn't, and I can't find
that. For example, in s. 7.12.1 para 4, it says that HUGE_VAL is
a guaranteed result only in the default rounding mode.
Appendix F says, in s. F.9 para 10, "Whether the [elementary]
functions honour the rounding direction mode is
implementation-defined." but this doesn't allow the functions to
produce invalid results, just to ignore the mode and use some other
mode instead. A good math library should honour the current rounding
mode, as this is what is most useful.
- Geoffrey Keating <email@example.com> <firstname.lastname@example.org>