Strange. I rechecked my reproduction on several machines and got the same result.
It seems this issue was already raised in BUG #18490, but the reproduction itself differs from mine.
> On 25 Apr 2025, at 13:51, Dilip Kumar <dilipbalaut@gmail.com> wrote:
>
> On Fri, Apr 25, 2025 at 11:54 AM PG Bug reporting form
> <noreply@postgresql.org> wrote:
>>
>> The following bug has been logged on the website:
>>
>> Bug reference: 18903
>> Logged by: Nikita Kalinin
>> Email address: n.kalinin@postgrespro.ru
>> PostgreSQL version: 17.4
>> Operating system: ubuntu 22.04
>> Description:
>>
>> Hello. I might be doing something strange, but I’d like to understand why
>> this all ends with a SIGABRT.
>> After building PostgreSQL like this:
>> ./configure --enable-tap-tests --enable-debug --with-openssl
>> --enable-cassert --prefix=/tmp/pg && make -j8
>> And running these two files:
>
>
> I tried using the steps you provided, but had no luck. While testing,
> I noticed that a lot of steps [1] in your test will fail because the
> vacuum can not be run within a transaction block. Is that part of
> reproducing the issue? I am looking through the call stack.
> Meanwhile, if you can recheck the steps you provided, then it would be
> helpful for analysis.
>
> [1]
> BEGIN;
> CLUSTER pg_class USING pg_class_oid_index;
> CLUSTER pg_class USING pg_class_oid_index;
> VACUUM FULL pg_class;
> VACUUM FULL pg_class;
> VACUUM FULL pg_class;
>
> --
> Regards,
> Dilip Kumar
> EnterpriseDB: http://www.enterprisedb.com