Libcxxabi standalone build

The libcxxabi page at Describes the steps
to do a "standalone" build. However, it is still looking for
LLVM_CONFIG and even if I put a proper llvm-config on the path, I get
errors of the kind:

CMake Error at /home/kfischer/julia-tls/usr/share/llvm/cmake/LLVMExports.cmake:9
  set_property could not find TARGET LLVMObject. Perhaps it has not yet been
Call Stack (most recent call first):
  /home/kfischer/julia-tls/usr/share/llvm/cmake/LLVMConfig.cmake:43 (include)
  CMakeLists.txt:55 (include)

Does standalone here not mean without llvm? That seems a rather
arbitrary requirement in that case given that the buildit script will
just build it, no questions asked. Can somebody enlighten me on the
history here?