[PATCH] D19542: [sanitizers] [NFC] Add defines for the various PowerPC

[Marcin Kościelnicki via llvm-commits]

koriakin added a comment.

In http://reviews.llvm.org/D19542#412410, @aizatsky wrote:

> As long as you are sure that  __BYTE_ORDER__ and _CALL_ELF means the same.


It doesn't really, but _CALL_ELF is the correct one.

The story is: there are two ABIs for ppc64 (determined by _CALL_ELF) and two endians. Originally, only BE was used.  One day, they decided to transition to LE for whatever reason, and made a new ABI while they were at it.  So if you configure for powerpc64, you get BE and v1, while configuring for powerpc64le results in v2.  It is possible to convince gcc (but not llvm) to compile for other combinations via some -m options, but you won't find such cases in the wild (someone would have to compile a full system like that, and it's quite painful).


Repository:
  rL LLVM

http://reviews.llvm.org/D19542