Subject: Re: soft-float builds
To: Simon Burge <firstname.lastname@example.org>
From: Jason R Thorpe <email@example.com>
Date: 05/30/2001 07:37:23
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.
> 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
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...
Actually, are there ELF header bits that indiciate "uses FPU"? I know
there are for MIPS...
-- Jason R. Thorpe <firstname.lastname@example.org>