PowerPC binary tagging

[Paul Brook]

> Has anyone thought about implementing this for PowerPC?  Do we have
> spare ELF header bits, or should we use a separate section?  The
> closest think I know if is the .PPC.EMB.apuinfo section, used to tag
> SPE binaries, but that's coprocessor usage rather than ABI.
>
> ARM has an extremely thorough solution to this problem - I don't know
> if we want anything as thorough for PPC to be honest.  See Section 2,
> Build Attributes.
>
>   http://www.arm.com/pdfs/ABI-addenda.pdf

FWIW I recommend using a table in a section (or PT_* in an image) rather 
a "spare ELF header bits". ISTR there being several targets where have have 
run out of bits or ended up with ambiguous bit meanings.

Paul