rL284708 introduces a link error when building with BUILD_SHARED_LIBS:
undefined reference to `llvm::DWARFContext::parseCompileUnits()' undefined reference to `llvm::DWARFContextInMemory::DWARFContextInMemory( llvm::object::ObjectFile const&, llvm::LoadedObjectInfo const*)'
The functions are available in libDebugInfoDWARF, from llvm.