Re: 440 ebony patch seems to have broken 85xx build on powerpc.git

[David Gibson <david@gibson.dropbear.id.au>]

On Fri, May 25, 2007 at 12:02:44AM +0200, Segher Boessenkool wrote:
> >>> Nothing is telling GCC what CPU to compile for, so it
> >>> will just use the compiler's default, which very likely
> >>> is not what you want.  For files that will only ever
> >>> be used on 440, the correct flags are -mcpu=440 -Wa,-m440 .
> >>
> >> We could add that to the per-file flags already, right?
> >
> > I think it should really use -mcpu=powerpc on all files.
> > The problem that Dave saw was the result of using a compiler
> > that defaults to -mcpu=8540, which uses instruction that
> > don't work on 440.
> 
> No, those options _do_ work on 440, but the -mbooke
> assembler flag disallows isel (since it is an optional
> insn).

But not on 440GP, which is what Ebony is.

> > The common files really need to be built with -mcpu flags that
> > make the code work on any system if you want to be able
> > to use just a single boot wrapper binary for all.
> 
> On any system where they can run at all, yes.  It should
> be fine to compile a 440-only file with 440-specific flags.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
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