PATCH: handle mach-o in bfd_get_sign_extend_vma

[Nick Clifton]

Hi Tristan,

> bfd/
> 2008-11-06  Tristan Gingold  <gingold@adacore.com>
>     
>     * bfd.c (bfd_get_sign_extend_vma): Return 0 for mach-o.

Approved - please apply.

Cheers
   Nick