Support PowerPC 64-bit ELF v2 ABI on big-endian systems
On PowerPC 64-bit GHC assumes that big-endian systems run ELF v1 and little-endian ELF v2. This was and is still true for most Linux distributions except Void Linux. Also FreeBSD switched to ELF v2 for release 13.
ELF v2 can be detected by a test for C compiler macro _CALL_ELF
, which must be defined on all ELF v2 compliant systems.