https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96973
--- Comment #6 from Iain Sandoe <iains at gcc dot gnu.org> ---
(In reply to Francois-Xavier Coudert from comment #4)
from fat.h
FAT headers are always written bigendian
* at least there's no statement revoking that in the section on FAT64
* it doesn't seem that the FAT64 format is considered stable yet - so we might
need to experiment,
There's no statement that says the FAT64
> if (is_64)
> - memcpy (&fat_arch,
> - (const char *) arch_view.data + i * arch_size,
> - arch_size);
> + {
> + memcpy (&fat_arch,
> + (const char *) arch_view.data + i * arch_size,
> + arch_size);
> + if (swapped)
> + fat_arch.offset = __builtin_bswap64 (fat_arch.offset);
> + }
> else
> {
> struct macho_fat_arch fat_arch_32;
> @@ -809,7 +813,10 @@ macho_add_fat (struct backtrace_state *state, const
> char *filename,
> arch_size);
> fat_arch.cputype = fat_arch_32.cputype;
> fat_arch.cpusubtype = fat_arch_32.cpusubtype;
> - fat_arch.offset = (uint64_t) fat_arch_32.offset;
> + if (swapped)
> + fat_arch.offset = (uint64_t)
> __builtin_bswap32(fat_arch_32.offset);
> + else
> + fat_arch.offset = (uint64_t) fat_arch_32.offset;
So in the case of 32b FAT entries...
We also need to swap any other items we use (and before promoting to 64b in the
case of the size.)
> fat_arch.size = (uint64_t) fat_arch_32.size;
> fat_arch.align = fat_arch_32.align;
> fat_arch.reserved = 0;
