Patch file for OS X

[Torbjorn Granlund]

Leif Leonhardy <not.really at online.de> writes:

  mode32 is only valid on PowerPCs (as opposed to Intel Macs), only
  necessary if you're running 32-bit MacOS X on a 64-bit PPC CPU, and
  MacOS X on PPC implies <= 10.5[.8] (Darwin 9 or earlier).
  
Well, mode32 is never "necessary", it is a GMP mode (or as we slightly
incorrectly call it, ABI) for 64-bit PPC processors in 32-bit mode,
using 64-bit 'limbs'.

One may also use a plain 32-bit build with 32-bit limbs.

Not much attention has been given to mode32 optimisation, since we
expect mode64 to be used by almost everybody with these CPUs.

Torbjörn