Standalone build of clang possible?

Is it possible to do a standalone build of clang, i.e. using LLVm from
the distro instead of building LLVM?

The instructions at http://clang.llvm.org/get_started.html only mention
building LLVM with clang.
At https://gist.github.com/kwk/9617978 there is a project (that I didn't
try yet) for a standalone build vs. LLVM 3.5.

I'm mostly interested in doing a standalone build of clang vs. LLVM 3.8.

Philipp

Actually I found it is possible. I just didn't see it earlier due to my
unfamiliarity with cmake. The only change necessary was in
CMakeLists.txt to specify llcm-config-3.8.
Sorry for the noise.

Philipp