From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jacob Champion <jacob.champion@enterprisedb.com>
cc: Michael Paquier <michael@paquier.xyz>,
        pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Fix up misuse of "volatile" in contrib/xml2.
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Comments: In-reply-to Jacob Champion <jacob.champion@enterprisedb.com>
	message dated "Thu, 10 Jul 2025 10:21:51 -0700"
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Date: Thu, 10 Jul 2025 13:27:59 -0400
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Jacob Champion <jacob.champion@enterprisedb.com> writes:
> On Wed, Jul 9, 2025 at 8:55=E2=80=AFPM Michael Paquier <michael@paquier.=
xyz> wrote:
>> On Wed, Jul 09, 2025 at 11:49:55AM -0400, Tom Lane wrote:
>>> Not sure.  Yesterday I saw such warnings from arowana,
>>> boa, dhole, rhinoceros, and shelduck, eg

>> They are all using some gcc 4.X flavor, most with -O2 but not all.

> I think I remember that GCC has had historical problems with tuning
> the false-positive:false-negative rates for `-Wmaybe-uninitialized`.
> It's not super surprising to me that later versions aren't always
> better at seeing specific problems, especially if users were
> complaining that an earlier version was too sensitive...

Yeah.  Worth noting also is that even the machines that were
complaining were warning about just a subset of the xpath.c functions
that had this problem :-(.  So there's definitely some heuristics
involved, which seems odd for what feels like it ought to be a
pretty black-and-white condition.

			regards, tom lane