Re: One more oddity with gcc and vax floats...

Johnny Billquist <[email protected]> Wed, 10 Jun 2026 13:41:30 +0200
Newsgroups gmane.os.netbsd.ports.vax
Message-ID <[email protected]>
On 6/10/26 08:30, matthew green wrote:
>> This is just one more problem with non-IEEE floating point. Since this
>> is a battle that cannot be won maybe I should put the dust of the
>> "Emulate IEEE floating point" stuff I once worked on.  Must read up on
>> the IEEE 754 standard first though.
> 
> i wouldn't hate this. :-)

I'm not convinced. Starting to do all FP math in software will be 
costly, on a machine that is already suffering heavly with performance 
issues.

> it is one of the more annoying, common, problems when trying to
> build modern software on vax.

True. Sadly, most of the time it isn't really an issue with the actual 
software as such, but either a problem with tests, or an expectation of 
Inf and/or specific forms of NaN existing on the machine. Tests are hard 
to fix, but most of the time the code that use Inf/NaN will work just 
fine by changing it to something that exists on a VAX.

>>          movd $0d-Inf,-(%sp)
> 
> we should still figure out and fix these though :)

That seems very broken, yeah.

   Johnny