[LLVMdev] Libcxx buildbot

[Renato Golin]

Hi folks,

I've updated the configuration for my libcxx buildbot (r220701) to
pass some additional flags to compilation, including setting the CPU
(so it won't need to use soft divide) and link flags + compiler-rt
dependency to lit (so it won't fail with __aeabi_* symbols missing).

Most problems should be all fixed once we reload the configuration in
the build master.

Right now, there's only one failure remaining, which I'm investigating.

backtrace_test.cpp:59: int main(): Assertion `nothrow_ntraced > 1' failed.

cheers,
--renato