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Re: IEEE NaN problems on Arm (as triggered by the r-base package)



On Mon, Jan 07, 2002 at 11:29:56AM +0000, Peter Naulls wrote:
> > 
> > As shown below, the issues seems to be the non-standard treatment of NaN
> > values.  Has think come up from other packages?  Does anybody here see a
> > workaround, or have other suggestions?
> > 
> > Thanks,  Dirk
> 
> The only thing unusual about IEEE values on ARM is that the word
> ordering of doubles is opposite to that on x86.  I suspect that it's
> this you're running into.   Many compilers have special cases for this.
> 
> Otherwise, to the best of my experience (apart from some minor quirks of
> which x86 also has its fair share) ARM behaves totally as expected for
> IEEE operations.

I was also under the impression that the FP emulation is pretty close
to IEEE standard.  I could be way off base, but I seem to recall that
gdb has issues with FP on ARM, so i'm not sure your tests using it are
valid.  Can you reproduce the same problem with a simple test program
(eg. not under the debugger)?

-R

(yes, I'm a newcomer to this list, but hopefully most know me from
netwinder.org...  and yes, I do intend to install Debian on one of my
'winders one of these days!)



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