From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Daniel Gustafsson <daniel@yesql.se>, Michael Paquier <michael@paquier.xyz>,
        BharatDB <bharatdbpg@gmail.com>, torsten.rupp@gmx.net,
        pgsql-bugs@lists.postgresql.org, VASUKI M <vasukim1992002@gmail.com>
Subject: Re: BUG #19095: Test if function exit() is used fail when linked static
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Fri, 14 Nov 2025 09:01:06 -0500"
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Date: Fri, 14 Nov 2025 09:40:46 -0500
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Andres Freund <andres@anarazel.de> writes:
> But more generally: If we allow pthread_exit(), what's the point of this=
 test?
> That's one of the functions we better avoid calling, no?

ATM it's not something we'd be tempted to call, but I take your point.

> ISTM that if we do want to continue having this test, the issue is that =
we're
> testing the shared library - which will have already linked against stat=
ic
> libraries like the sanitizer ones or in this case libcrypto. What we oug=
ht to
> do is to test the .o files constituting libpq.so, rather than the alread=
y
> linked .so. That way we will find our own calls to exit etc, but not one=
s in
> static libraries.

My recollection is that that doesn't help as much as you'd think.
__tsan_func_exit, for one, can get injected into our own .o files
if we build with appropriate sanitizers enabled.

			regards, tom lane