You can capture a CPU snapshot and send it to clion-support at jetbrains.com, we will analyse it.
Also you can try disabling `C/C++ | Data flow analysis`, `C/C++ | Unused code` and `General | Simlifiable statement` inspections on the `Preferences | Editor | Inspections` tab, it might help.
https://intellij-support.jetbrains.com/hc/en-us/community/posts/360001507919-CLion-use-600-of-CPU
