Subject: Re: Segmentation fault when calling BlessTupleDesc in a C function in
 parallel on PostgreSQL-(12.6, 12.7, 13.2, 13.3)
To: Thomas Munro <thomas.munro@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>,
 Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>,
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From: Eric Thinnes <e.thinnes@gmx.de>
Message-ID: <e2b363f1-c886-a268-902b-0b5352b778cc@gmx.de>
Date: Mon, 17 May 2021 09:01:01 +0200
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 > PG 11, before that there was a different arrangement involving
 > translation), but there is a low probability edge case that your test
 > manages to hit fairly reliably, where two backends try to bless a

I see that I have a talent for stepping into the trap.

 > record_table_entry->key.u.shared_tupdesc);
 >                  Assert(result->tdrefcount == -1);
 >
 > With that change I can see it still hits this path often but works
 > correctly.  Will fix next week.


That is good news.

This means that all users can benefit from it.