Re: RFC & patch: Rework MIPS command-line handling

[Thiemo Seufer <ica2_ts at csv dot ica dot uni-stuttgart dot de>]

Richard Sandiford wrote:
> [Answering two messages together]
> 
> cgd@broadcom.com writes:
> > At Mon, 15 Jul 2002 17:54:45 +0000 (UTC), "Thiemo Seufer" wrote:
> > > There seems to be some misconception about the term 'ABI', maybe
> > > because the current -mabi=FOO option basically means "select calling
> > > conventions and register sizes". But an ABI is a much more powerful
> > > concept than pushing a few compiler options. It defines a platform
> > > over a variety of hardware which allows to run the same binary code.
> 
> Hmm... I thought "o32" was a term that SGI invented.  And (going
> from the n32 handbook and SGI's cc) their idea of "o32" includes
> the ability to run MIPS II code.

Hm, some of SGI's (very old) hardware running o32 is MIPS I. Maybe
they invented some MIPS II emulation on it, or they simply don't
support MIPS I systems any more.

> Granted, the System V supplement says:
> 
>     Some processors might support the MIPS I ISA as a subset, providing
>     additional instructions or capabilities, e.g., the R6000 processor.
>     Programs that use those capabilities explicitly do not conform to
>     the MIPS ABI.
> 
> but does -mabi=32 select the ABI defined there, or does it
> work like SGI's -32 option?  I assumed the latter.

IMHO -mabi=32 should work ok on all targets, not only on SGI. :-)


Thiemo