Feedback-ID: i0fe9450f:Fastmail
Date: Wed, 4 Dec 2024 07:41:19 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
Cc: Amit Kapila <amit.kapila16@gmail.com>,
	Postgres hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Memory leak in WAL sender with pgoutput (v10~)
Message-ID: <Z0-JD3F-fBx8IwlL@paquier.xyz>
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On Tue, Dec 03, 2024 at 02:45:22PM +0100, Alvaro Herrera wrote:
> We can put the new member at the end of the struct, it shouldn't damage
> anything even if they're using this struct -- which I find pretty
> unlikely.  The only way that could break anything is if somebody is
> allocating/using arrays of it, which sounds even more unlikely.

Yes, that sounds unlikely. =20

> If we don't want to accept that risk (for which I see no argument, but
> happy to be proven wrong), I would suggest to use the foreach-pfree
> pattern Michael first proposed for the backbranches, and the new memory
> context in master.  I think this is conducive to better coding overall
> as we clean things up in this area.

Is it really worth betting on nobody doing something that does a
sizeof(PGOutputData) for the stable branches?  People like doing fancy
things, and we would not hear about such problems except if we push
the button making it a possibility because compiled code suddenly
breaks after a minor release update of the core engine.
--
Michael

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