Investigating /MP with MSVC

Digging into the above, I noticed this file CMake/CompileFlags.cmake at master · Kitware/CMake · GitHub. Which at the very bottom has mention of /MP and how it’s controlled.

What is the purpose of this file? Whilst it’s there in git, it doesn’t seem to feature in the final product (not on Windows at least).

How does this file get used?

Ah - so I believe I’ve worked out that this cmake file is actually for building cmake itself and not involved in the end product.