"-- The C compiler identification is unknown" when building MySQL on Win

It may be nightmare to troubleshoot if CMake shows errors on Windows. Various meaningless errors were shown, but the most important thing is to try to troubleshoot errors in CMakeFiles/CMakeError.log file.

In particular, my "-- The C compiler identification is unknown" error was solved by removing ComponentModelCache in
C:\Users\user\AppData\Local\Microsoft\VisualStudio\11.0\

CMake worked smoothly afterward.