Feedback-ID: id4a34324:Fastmail
Date: Fri, 27 Mar 2026 17:17:49 -0400
From: Andres Freund <andres@anarazel.de>
To: Michael Paquier <michael@paquier.xyz>
Cc: Andreas Karlsson <andreas@proxel.se>, Tom Lane <tgl@sss.pgh.pa.us>,
	pgsql-hackers@lists.postgresql.org
Subject: Re: Our ABI diff infrastructure ignores enum SysCacheIdentifier
Message-ID: <vlcexdcimsmvu3aplt2yxpfndkgtuvjsrms2fdl46rbw3k2kug@drspkoxlaije>
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Hi,

On 2026-02-18 11:34:19 +0900, Michael Paquier wrote:
> The buildfarm is not complaining after c06b5b99bbb0 and ee642cccc43c,
> meaning that we are hopefully good for v19 and future versions.

I'm not happy that this change exposed syscache.h much more widely. Before
ee642cccc43c syscache.h was not included by any header. Now it is very widely
included, via objectaddress.h, which in turn is included by a lot of other
headers.

With ee642cccc43c a change to syscache.h rebuilds 632 files. With ee642cccc43c
reverted, it's just 196.

Leaving build impact aside, I don't think it's good to expose a relatively low
level detail like syscache.h to most of the backend. It's imo something that
only .c, never .h files should need.

Greetings,

Andres Freund