The crash in question has a project that uses this particular implementation of the AsyncTaskMethodBuilder: https://github.com/Cysharp/UniTask/blob/master/Assets/UniRx.Async/CompilerServices/AsyncUniTaskMethodBuilder.cs

The catch is this implementation does not contain a ObjectIdForDebugger accessor and therefore hits the assert in debugger-agent.c 's : get_object_id_for_debugger_method because it assumes that it will be there.

Steps to Reproduce

I don't have a repro at the moment outside of Unity. If you need one let me know and I can get one prepared.

Current Behavior

Crashes after hitting the following assert:
g_assert (array->len == 1);

Expected Behavior

No crash.

On which platforms did you notice this

[X] macOS
[ ] Linux
[X] Windows

Version Used:
Reproduced using latest mono/master