[illumos-Developer] Ugh... xdr_{float,double} problems

[Jason King]

On Tue, Feb 1, 2011 at 3:30 AM, Joerg Schilling
<Joerg.Schilling at fokus.fraunhofer.de> wrote:
> "Garrett D'Amore" <garrett at nexenta.com> wrote:
>
>> It sounds like all the main CPU targets support IEEE 754.  The only
>> reasonable (?) question IMO is S390.  Roland?  Neale?
>
> If I interpret the floating point code written by David M. Gay from AT&T
> correctly, then IBM and VAX are the two mayor deviations from IEEE.
>
> But HPPA uses at least different parameters for long double than other IEEE
> architectures do.
>
> Jörg

Just to get back to the question at hand.  Is it reasonable to assume
if someone is going to port Illumos to a platform that doesn't support
IEEE 754 to have them write conversion code (that can utilize
knowledge of the native format during the conversion) instead of a
generic routine that is both slow and very likely to introduce greater
rounding errors?

If so, I will just remove the portable code altogether and just emit a
compiler error to notify porters.  If not, I will revert it to an
#ifdef to select between the two implementations.