why is clang-3stage-ubuntu disabled in buildbot/osuosl/master/config/builders.py?

Does anyone know why the clang-3stage-ubuntu build bot is disabled at...


On darwin, we seeing non-deterministic behavior in llvm trunk since
4.0.0 was branched off.


It would be wise to re-enable that buildbot to get some coverage for
checks on non-deterministic code generation on linux.
ps It is unclear if anyone has ever adjusted
tools/clang/cmake/caches/3-stage.cmake to allow it to work on darwin
so the non-deterministic code generation checks using that may have to
be done on linux.