Tom,
No, it's not a bug but it is an an (completely unverified) potential
issue inside our serialization code. The test was added to see how
prevalent non-IEEE floating point types are (which is actually
exceptionally prevalent). Whether and implementation is complaint is
dependent on compilation options and your hardware type. If it's
always done it for you, it's undoubtedly just a nature of your
hardware type that GCC is taking advantage of.
You can sometimes force IEEE floating point with a gcc option (like -
mieee), but those are similarly dependent on your hardware type.
The impact of the bug is that we have one place in the code that
assumes an IEEE floating point encoding when writing single-precision
floating point values out to .g files. Fortunately, we rarely ever
use single-precision floating point (not a single location comes to
mind actually, but probably somewhere) but the potential issue would
be a floating point value that was stored/serialized on one (non-IEEE
compliant) platform into a .g file would appear as a different value
when that .g were read/deserialized on a different (IEEE-compliant)
platform.
Basically it's a warning/TODO item to verify the serialization
behavior at some point.
Cheers!
Sean
On Jan 9, 2009, at 12:56 PM, Tom Browder wrote:
> Sean, I get the following message (and I guess I always have with gcc)
> with gcc 4.3.2:
>
> configure: }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
> configure: WARNING: The floating point implementation does not seem to
> be IEEE 754
> configure: WARNING: compliant. The behavior of htond and htonf may be
> incorrect.
> configure: {{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{
>
> Is that a gcc bug?
>
> BTW, I don't see 7.14.0 in the News on the web site.
>
> Happy New Year to all.
>
> -Tom
>
> ----------------------------------------------------------------------
> --------
> Check out the new SourceForge.net Marketplace.
> It is the best place to buy or sell services for
> just about anything Open Source.
> http://p.sf.net/sfu/Xq1LFB
> _______________________________________________
> BRL-CAD Developer mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/brlcad-devel
------------------------------------------------------------------------------
Check out the new SourceForge.net Marketplace.
It is the best place to buy or sell services for
just about anything Open Source.
http://p.sf.net/sfu/Xq1LFB
_______________________________________________
BRL-CAD Developer mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/brlcad-devel
