[avahi] How to enable avahi debug log messages?

[Elias Rudberg]

Hello,

I am having this avahi assertion failure problem:

https://bugs.launchpad.net/ubuntu/+source/avahi/+bug/1820584

In the code I see some avahi_log_debug(...) calls and I was thinking 
that if that logging was enabled maybe it would give some clues about 
what goes wrong.

How is debug logging enabled?

Are there other debug features that could be used to investigate 
problems like the above assertion failure, if so how to turn those on?

This is in Ubutu 20.04 with avahi 0.7.

Best regards,
Elias