Date: Mon, 25 Aug 2025 11:46:35 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Sami Imseih <samimseih@gmail.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: GetNamedLWLockTranche crashes on Windows in normal backend
Message-ID: <aKyTa-iOdAfKynI1@nathan>
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On Fri, Aug 22, 2025 at 02:21:55PM -0500, Sami Imseih wrote:
> While working on [0], I observed that $SUBJECT. I encountered this issue
> while building test cases for [0], and in which GetNamedLWLockTranche is
> called outside of startup.
> 
> [...]
> 
> I repro'd this on a Windows machine, but one can also enable EXEC_BACKEND
> in pg_config_manual.h and call GetNamedLWLockTranche by a normal backend.
> 
> I did this by injecting
> ```
> GetNamedLWLockTranche("pg_stat_statements");
> ```
> inside pgss_ExecutorEnd

If this fails, why doesn't the call in pgss_shmem_startup() also fail?  Was
pg_stat_statements not loaded via shared_preload_libraries?  And is the
failure a segfault or a "requested tranche is not registered" error?

-- 
nathan