[RFC] Fix PR28684

Richard Guenther rguenther@suse.de
Tue Nov 14 22:00:00 GMT 2006


On Tue, 14 Nov 2006, Clint Whaley wrote:

> Guys,
> 
> Sorry for the delay in responding the ongoing discussion, I'm pretty snowed
> under at the moment.  However, let me take a minute to respond to the questions
> that seem to have been directed my way.
> 
> Most importantly, my request had to do with IEEE compliance, not FLOP count.

"IEEE compliance" is still somewhat a vague statment, but I guess you
refer to IEEE 754/854?  For example -ffast-math on x86_64 disables
the handling of denormals and flush-to-zero behavior, which violates
IEEE - do you care?  It also specifies basic arithmetic and rounding,
which makes association and contraction a violation of IEEE.

So appearantly you have a more "useful" subset of IEEE you care about?
We're trying to provide that with -funsafe-math-optimizations -- what in
-funsafe-math-optimizations is that you cannot use it?  -ffast-math
also "disables" NaNs and Infs and floating point exceptions, which makes
it a "stronger" violator of IEEE.

Richard.

--
Richard Guenther <rguenther@suse.de>
Novell / SUSE Labs



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