Date: Tue, 24 Mar 2026 16:47:30 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Andres Freund <andres@anarazel.de>
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
Message-ID: <acMGcoUwA9CiPPU1@nathan>
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On Fri, Mar 20, 2026 at 04:32:48PM -0400, Andres Freund wrote:
> 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.

Here is a first try.

-- 
nathan

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