I understand. Can you tell me a bit more about the environment that you are using? I compile fine using cmake and clang under linux and macosx, but have never tried on windows.
You could start by looking at the options
cmake --help has to automatically build a project. If none are with clang, try googling how to create a clang project from cmake. I think it is much easier if you create a project using cmake.
Let me know how it goes.