Re: [patch] Re: Linux 2.4.5-ac6

[Jeff Garzik <jgarzik@mandrakesoft.com>]

"Maciej W. Rozycki" wrote:
> 
> On Wed, 6 Jun 2001, Ivan Kokshaysky wrote:
> 
> > > No need to patch arch_get_unmapped_area(), but OSF/1 compatibility code
> > > might need fixing.  I suppose an OSF/1 binary must have an appropriate
> > > flag set in its header after building with the -taso option so that the
> > > system knows the binary wants 32-bit addressing.
> >
> > I'm not sure if COFF headers have such flag at all. I'll check this.
> 
>  Then how does OSF/1, especially the dynamic linker, know if a binary
> needs 32-bit addressing?  I suppose we could use the same way of
> selection.

There are two things you can do here, one is easy:  use linker tricks to
make sure that an application built on alpha -- with 64-bit pointers --
uses no more than the lower 32 bits of each pointer for addressing. 
This should fix a ton of applications which cast pointer values to ints
and similar garbage.

The other option, hacking gcc to output "32-bit alpha" binary code, is a
tougher job.

I had mentioned this to Richard Henderson a while back, when I was
wondering how easy it is to implement -taso under Linux, and IIRC he
seemed to think that linker tricks were much easier.

	Jeff


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Jeff Garzik      | An expert is one who knows more and more about
Building 1024    | less and less until he knows absolutely everything
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