Re: CVS commit: src/lib/libm

[Taylor R Campbell <riastradh%NetBSD.org@localhost>]

> Date: Wed, 30 Oct 2024 04:30:44 +0900
> From: Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>
> 
> riastradh@ wrote:
> 
> > Is this configuration
> > relevant for real-world hardware or is it more of a `for fun' option?
> 
> The only use case is to run NetBSD/mac68k on XC68LC040 machines.
> 
> It looks he "options FPU_EMULATE" for m68k doesn't handle
> XC68LC040 errata properly so most FP programs randomly dumps core
> on it (though FPU_EMULATE works on rare MC68LC040).
> 
n> In the real world only several Machintosh machines (LC630 etc.)
> were shipped with XC68LC040 and users of such machines want
> softfloat, but most such geek users just replaced LC040 with 68040.
> 
> I have LC630 with MC68LC040 and HP9000/382 with (replaced) XC68LC040
> to debug FPU_EMULATE on LC040, but it has been in my deep todo list..

Cool, thanks for the background!

> > Maybe we should have an m68k MKSOFTFLOAT=yes autobuild?
> 
> We can do it, but IIRC there were several discussions if we provide
> softfloat m68k binaries maybe we should define a differnt MACHINE_ARCH.

Yes, I think we need a new MACHINE_ARCH for that, maybe m68ksf.  But
maybe effort is better spent on making FPU_EMULATE work than on
dealing with a new ABI.