Fixing warnings in back branches?

Hi,

While newer branches are at the moment mostly free of warnings for me,
the picture is entirely different in the older back branches, especially
9.1. That has several hundred lines of warnings.

I personally am not bothered by a handful of spurious warnings in the
back branches, but at this point you're very unlikely to see a new
warning introduced into 9.1 while backpatching.

Should we perhaps fix the worst offenders?

Greetings,

Andres Freund