7:03 -- you should prefer to use find_package(LLVM REQUIRED CONFIG) and then set -DLLVM_DIR at the CMake command line for precisely this purpose. Also if Clang weren't bugged by not including Clang_DIR, you could just add your PATH_TO_LLVM to the CMAKE_MODULE_PATH variable. This would be the preferred solution, as I understand it.
7:03 -- you should prefer to use find_package(LLVM REQUIRED CONFIG) and then set -DLLVM_DIR at the CMake command line for precisely this purpose. Also if Clang weren't bugged by not including Clang_DIR, you could just add your PATH_TO_LLVM to the CMAKE_MODULE_PATH variable. This would be the preferred solution, as I understand it.
This is indeed preferred solution, and we switched to it eventually, but IIRC it was broken around Clang/LLVM 5.0 on Ubuntu, therefore this hack.
This is basically his blog entry: lowlevelbits.org/building-an-llvm-based-tool.-lessons-learned/
The blog post is a follow-up to this talk in a text form