[LLVMdev] Lib C++ buildbot problem

[Renato Golin]

Folks,

I'm trying to set up a libc++ buildbot on ARM and I found an
inconsistency which I'm not sure how to fix.

I got a build error like this:

libc++abi.so: undefined reference to `_Unwind_GetGR'

Since I expected that the symbol would be provided by that library, I
searched the CMake on libc++abi and found this:

option(LIBCXXABI_USE_LLVM_UNWINDER "Build and use the LLVM unwinder." OFF)
...
if (LIBCXXABI_USE_LLVM_UNWINDER)
  add_subdirectory(src/Unwind)
endif()

But on the Libc++AndAbiBuilder, there's no way to set the CMake
argument (or is there?):

def getLibcxxAndAbiBuilder(f=None, env={}, additional_features=set()):

"additional_features" seem to imply only lit test args, not anything else.

Ideas?

cheers,
--renato