Feedback-ID: id4a34324:Fastmail
Date: Fri, 20 Mar 2026 16:32:48 -0400
From: Andres Freund <andres@anarazel.de>
To: Nathan Bossart <nathandbossart@gmail.com>
Cc: Michael Paquier <michael@paquier.xyz>,
	shihao zhong <zhong950419@gmail.com>,
 PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: Fixes inconsistent behavior in vacuum when it processes multiple
 relations
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Hi,

On 2026-03-20 14:39:11 -0500, Nathan Bossart wrote:
> On Fri, Mar 20, 2026 at 12:27:49PM -0400, Andres Freund wrote:
> > Why wasn't it enough to add const markers and keep passing by pointer?
> 
> IIRC the idea was to prevent similar problems in the future.

Seems using const VacuumParams *params should suffice for that? I don't think
it's particularly likely that we'll accept code that casts the const away and
then later get hurt by that.


> To avoid the extra #includes, we could instead use the back-patched version
> (e.g., commit 661643deda).

I'd probably not go quite there, at least the params should largely be const,
with a local on-stack copy where we do need to modify.

Greetings,

Andres Freund