Esthetics (or worse?) of Secure Pointers

[Michael Meissner]

On Tue, Apr 17, 2001 at 07:40:48PM -0700, John Gilmore wrote:
> > For a backup plan, I think it's sufficient to mandate no mixing of BP
> > and non-BP compilation units, distinguished by a special symbol,
> > enforced by ld.  Anyone violently disagree?
> 
> Yes, I disagree.
> 
> ELF and many other formats have a field in the file header for what
> architecture the object file contains.  Pick a new architecture
> specifier when compiling for an architecture with larger pointers.
> Just as big-endian and little-endian code compiled for the same chip
> gets different architecture types, big-pointer and little-pointer code
> for the same chip should be distinguished in this way.

Actually I would recomend using the data encoding field (byte #5), which
currently has 2 possible values (ELFDATA2LSB and ELFDATA2MSB for little endian
and big endian respectively), rather than try to duplicate N number of
different architectures.

> I'm pretty sure the linker already checks that you aren't mixing
> architecture types in your object files.
> 
> Use the abstractions we already have for what they are designed for,
> rather than making up new kludges for every special case...
> 
> 	John

-- 
Michael Meissner, Red Hat, Inc.  (GCC group)
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