Cleaning up base system warnings that clang will reject

Hi,

I built world with the warning suppressions in share/mk/bsd.sys.mk turned back on, plus a set of additional clang diagnostics, to see what the tree looks like without the WARNS ladder hiding things. I would like to start sending fixes, and I want to check the approach with hackers@ before I generate a pile of reviews.

By generate , I don't mean LLM generated.  I already have all the files unstaged, I just need to select the files, write a commit and assign subsystem reviewers.

Most of it is not interesting.

But the part I care about is the end, because clang keeps promoting these.
Clang 22 makes promoted a bunch already..

So the idea is that I prepare few diffs split by sub systems, and then we can land them.
I'm not pushing anything directly.
Sometime correcting a subsystem will make the maintainers want to rewrite them or refactor them fully. 

I already sent one of these separately (D59277, an inetd -Wuninitialized-const-pointer false positive that broke buildworld under
clang 21).

Best
Abdelkader