Date: Wed, 22 Apr 2026 14:22:09 -0500
From: Nico Williams <nico@cryptonector.com>
To: Jacob Champion <jacob.champion@enterprisedb.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
	Daniel Schreiber <daniel.schreiber@hrz.tu-chemnitz.de>
Subject: Re: PostgreSQL 17: Bug in libpq when libpq is dlopened/closed
 multiple times
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On Wed, Apr 22, 2026 at 11:29:04AM -0700, Jacob Champion wrote:
> > (I'd be surprised if this were the only such resource leak across all
> > supported versions and combinations of Kerberos, OpenSSL, OpenLDAP,
> > Curl, etc. etc. From a quick search, you're the first to report this
> > in the ten years since the leak was introduced, so there may be more
> > dragons where you're headed.)
> 
> If anyone has thoughts on that, I'd love to hear them. I don't mind
> removing this unnecessary code in HEAD, or even backpatching as a
> courtesy -- but if it were up to me, I would not guarantee zero global
> resource leaks across libpq and its entire dependency graph. (Even if
> we magically had control over all those dependencies, I think it'd
> still be reasonable for libpq devs to use "allocate once and move on"
> patterns... and I want to continue using those in my new code.)

Leaking a dl handle is a way to prevent unloading.  Not saying that's a
great answer, just that it's a workaround.