What is LLDB RPC Server ? When does it crash in Xcode? Why it crashes?

Question

I am getting a message in my debugger:

The LLDB RPC server has crashed. The crash log is located in ~/Library/Logs/DiagnosticReports and has a prefix

Answer 1

Clearly a lot of different causes for this, but for me I was using a DispatchGroup to keep track of multiple async tasks.

I had forgotten to call dispatchGroup.enter() before one of the async tasks (but still calling dispatchGroup.leave() when it finished).

Adding this in fixed the crash for me.