Date: Thu, 16 Jan 2020 21:21:28 +0100
From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>, Tomas Vondra <tv@fuzzy.cz>,
	pgsql-hackers@postgresql.org
Subject: Re: SlabCheck leaks memory into TopMemoryContext
Message-ID: <20200116202128.m7b76msbd5d6asmi@development>
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On Thu, Jan 16, 2020 at 03:15:41PM -0500, Tom Lane wrote:
>Tomas Vondra <tomas.vondra@2ndquadrant.com> writes:
>> I think the one possible argument against this approach might be that it
>> adds a field to the struct, so if you have an extension using a Slab
>> context, it'll break if you don't rebuild it. But that only matters if
>> we want to backpatch it (which I think is not the plan) and with memory
>> context checking enabled (which does not apply to regular packages).
>
>Huh?  That struct is private in slab.c, no?  Any outside code relying
>on its contents deserves to break.
>

Ah, right. Silly me.

>I do think we ought to back-patch this, given the horrible results
>Andres showed.
>

OK.

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services