Re: pg_stat_bgwriter.buffers_backend is pretty meaningless (and more?)

On 2023-02-26 15:08:33 -0500, Tom Lane wrote:
> Andres Freund <andres@anarazel.de> writes:
> > They're all animals for testing older LLVM versions. They're using
> > pretty old clang versions. phycodurus and dragonet are clang 3.9, petalura and
> > desmoxytes is clang 4, idiacanthus and pogona are clang 5.
> 
> [ shrug ... ]  If I thought this was actually good code, I might
> agree with ignoring these warnings; but I think what it mostly is
> is misleading overcomplication.

I don't mind removing *_FIRST et al by using 0. None of the proposals for
getting rid of *_NUM_* seemed a cure actually better than the disease.

Adding a cast to int of the loop iteration variable seems to work and only
noticeably, not untollerably, ugly.

One thing that's odd is that the warnings don't appear reliably. The
"io_op < IOOP_NUM_TYPES" comparison in pgstatfuncs.c doesn't trigger any
with clang-4.

Greetings,

Andres Freund