From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alexander Lakhin <exclusion@gmail.com>
cc: Andrew Dunstan <andrew@dunslane.net>,
        Nishant Sharma <nishant.sharma@enterprisedb.com>,
        Shruthi Gowda <gowdashru@gmail.com>,
        Mahendra Singh Thalor <mahi6run@gmail.com>,
        Fujii Masao <masao.fujii@gmail.com>,
        PostgreSQL Development <pgsql-hackers@postgresql.org>
Subject: Re: [BUG] CRASH: ECPGprepared_statement() and ECPGdeallocate_all()
 when connection is NULL
In-reply-to: <75460b3c-255d-47eb-b889-d99de38e6758@gmail.com>
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Comments: In-reply-to Alexander Lakhin <exclusion@gmail.com>
	message dated "Tue, 05 May 2026 23:00:00 +0300"
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Date: Tue, 05 May 2026 16:32:41 -0400
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Alexander Lakhin <exclusion@gmail.com> writes:
> There is no other useful information in the log, so it's not clear what'=
s
> wrong with that animal (no other gives us such failures), but I could
> produce something similar (on FreeBSD and Linux) with:
> echo "max_connections =3D 10" >/tmp/temp.config; TEMP_CONFIG=3D/tmp/temp=
.config gmake -s check -C src/interfaces/ecpg/test

Yes, I can also reproduce problems with the ecpg tests at
max_connections =3D 10.  For me, thread/prep segfaults but thread/alloc
just seems to hang indefinitely.  (thread/prep sometimes does too.)
These issues are not new; v18 does the same.  The reporting is a
bit different but I think that's from pg_regress changes not ecpg.

Looking at the postmaster log, I see

2026-05-05 16:11:06.509 EDT [682116] FATAL:  sorry, too many clients alrea=
dy

which is unsurprising in this situation, but apparently these tests
don't handle a connection failure well at all.

There's no such message in dikkop's log, so that may be an unrelated probl=
em.

BTW, reducing max_connections to 5 causes several other tests to fail,
but in unsurprising ways, like

# +SQL error: could not connect to database "ecpg1_regression" on line 107
# +SQL error: could not connect to database "ecpg1_regression" on line 107
# +SQL error: could not connect to database "ecpg1_regression" on line 107
# +SQL error: could not connect to database "ecpg1_regression" on line 107


			regards, tom lane