bug#69809: 30.0.50; flymake: error in process sentinel

[Eli Zaretskii]

> From: Gerd Möllmann <gerd.moellmann@gmail.com>
> Date: Fri, 15 Mar 2024 08:09:40 +0100
> 
> In master, I am sometimes getting errors like these:
> 
>   error in process sentinel: flymake--handle-report: Can’t find state for 
> flymake-cc in ‘flymake--state’
>   error in process sentinel: Can’t find state for flymake-cc in 
> ‘flymake--state’
>   error in process sentinel: flymake--handle-report: Can’t find state for 
> flymake-cc in ‘flymake--state’
>   error in process sentinel: Can’t find state for flymake-cc in 
> ‘flymake--state’
>   error in process sentinel: flymake--handle-report: Can’t find state for 
> flymake-cc in ‘flymake--state’
>   error in process sentinel: Can’t find state for flymake-cc in 
> ‘flymake--state’
> 
> when working with C files.
> 
> I haven't configured anything for Flymake myself. I think Flymake gets
> involved by using Eglot. The errors apparently don't prevent flymake
> from working later on.
> 
> I have looked around in flymake docs and source, but I can't figure out
> what's wrong.

Spencer, any suggestions?