Re: MATH_EMULATE

[Vit Herman <v.herman%sh.cvut.cz@localhost>]

On Mon, 14 Jan 2008, Daniel Carosone wrote:
> Sure, there are plenty of things to consider.  Here are a few more:
>
> - None of the netbsd developers disagrees with you, in that it would
>   be nice or desirable to have every possible system supported and
>   working.
>
> - However, someone needs to show up and do the work. Offers of
>   testing are all very well -- and absolutely essential and welcome --
>   but are not, in themselves sufficient, someone needs to write or
>   maintain the code that is to be tested too. Perhaps someone will in
>   this case.

I sure understand that offering testing is not enough, and I would offer 
more if I were sure that I could deliver the work - but I'm not.

> - So far it seems that the MATH_EMULATE code has bitrotted and is
>   broken, and may have been for some time.  So it's not just a matter
>   of somebody missing a mailing list posting announcing removal of
>   something that worked - it's also a case of nobody having reported
>   a bug about the problem in all that time.  That doesn't mean
>   nobody's using it on old versions, but it does strengthen the
>   perception that maybe it won't be much missed in the next release.

In my case, I was under the impression that the fact fpu emulation has 
bitrotten was widely know - my mistake probably. But yeah, I understand 
your point - the interest in it isn't strong - but still, there's some.

> - Removing MATH_EMULATE from the kernel *doesn't* mean machines
>   without FPU can't run netbsd, or won't be supported. It just means
>   that they will need their binaries compiled with -msoft-float,
>   rather than relying on emulated cpu insructions.  This will be
>   faster anyway, and such machines these days will be used for
>   special-purpose cases and will benefit in other ways from
>   special-purpose builds specific to their needs.

I understand that, but - are we really sure that it's MATH_EMULATE what is 
broken? If I understood it correctly, the failing ld.so.conf mechanism for 
switching libm versions could cause this problem as well. Correct me if 
I'm mistaken.

Vit Herman