Subject: Re: soft-float builds
To: None <email@example.com>
From: Simon Burge <firstname.lastname@example.org>
Date: 05/31/2001 12:10:38
Jason R Thorpe wrote:
> On Wed, May 30, 2001 at 10:22:08PM +1000, Simon Burge wrote:
> > What I was thinking was something along the lines of a
> > MKSOFTFLOAT= yes|no
> > make variable, which would do things like add "-msoft-float" to the CC
> > and CXX (and FC?) variables, and be used in the libc/arch/* makefiles
> > (or even just libc/Makefile) to enable softfloat support in libc.
> > Any comments on this, or better ways to do it?
> That sounds fine.
Cool. One "aye" and no "nay"s so far.
> > This raises a further question about whether or not we should have a
> > separate MACHINE_ARCH for softfloat-built userlands and what it should
> > be called (soft<arch>, soft-<arch>, ...). Any ideas here will be
> > appreciated...
> Yes, esp. for e.g. PowerPC, where it changes the ABI for e.g. stdarg. Do
> you have kernel FP emulation for FPU-less PowerPCs? If so, then you can
> still run FPU-using PowerPC code by emulating the register accesses, but
> that'll be slow...
We have kernel FP emulation, but yes, it's not quite as fast :) Early
userland work was done with macppc binaries.
> Actually, are there ELF header bits that indiciate "uses FPU"? I know
> there are for MIPS...
Do you have a reference for that? We don't seem to have any flags in
our source tree for those (that I can see)...
Simon Burge <email@example.com>
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