From: Tom Lane <tgl@sss.pgh.pa.us>
To: Michael Paquier <michael@paquier.xyz>
cc: Robert Treat <rob@xzilla.net>, Jim Jones <jim.jones@uni-muenster.de>,
        Postgres hackers <pgsql-hackers@lists.postgresql.org>,
        Erik Wienhold <ewie@ewie.name>
Subject: Re: Regression with large XML data input
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Comments: In-reply-to Michael Paquier <michael@paquier.xyz>
	message dated "Mon, 28 Jul 2025 11:09:33 +0900"
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Date: Sun, 27 Jul 2025 22:16:47 -0400
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Michael Paquier <michael@paquier.xyz> writes:
> On Fri, Jul 25, 2025 at 02:21:26PM -0400, Tom Lane wrote:
>> However, from Jim Jones' result upthread, a "minor update" of libxml2
>> could also have caused this problem: 2.9.7 and 2.9.14 behave
>> differently.  So we don't have sole control --- or sole responsibility
>> --- here.

> This sentence is incorrect after I have double-checked the behaviors I
> am seeing based on local builds of libxml2 2.9.7 and 2.9.14.

Hmm, okay, I misread Jim's results then.  But there still remains
the big question: what reason is there to believe that it's safe
to return to the old behavior?  If newer libxml2 versions report
XML_ERR_RESOURCE_LIMIT on the same input, doesn't it seem likely
that there's a live hazard in the old code?

			regards, tom lane