I wrote:
> Adding to my confusion, I do not see these warnings on a local
> RHEL9 machine, which ought to be pretty equivalent to CentOS 9.
Oh! I see part of the story: I was testing that with gcc.
If I switch to clang (version 20.1.8 here), then I see that
we pick "__syslog__" and then these complaints appear.
So why isn't clang being bug-compatible with gcc on the
names of printf archetypes? They're certainly pretty
slavish about that on most other topics.
regards, tom lane