I originally created the very basic CMakeLists.txt only for IDE support, so I can access the debug tools more comfortably.
When Freddy decided to use the same IDE, I decided to include it in the project, as it might be useful for any further devs running a non Microsoft IDE on Linux.
According to
his response on my PR in august, it's meant to eventually replace the two other build systems, but the work on it is not yet finished.
There still seems to be progress on that branch, the last one mentioning something about Windows, so I'd expect Windows support to be a thing, which might or might not work properly yet.
What do you mean by "cmake does not work on mingw"? That's quite contrary to the idea of CMake, which is to provide a platform independent build system.