From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrew Dunstan <andrew@dunslane.net>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: Residual cleanups for tied objects in PL/Perl
In-reply-to: <7e5de9c1-e2fe-44d2-9df3-670c6678e52b@dunslane.net>
References: <569769.1786901901@sss.pgh.pa.us>
 <7e5de9c1-e2fe-44d2-9df3-670c6678e52b@dunslane.net>
Comments: In-reply-to Andrew Dunstan <andrew@dunslane.net>
	message dated "Sun, 16 Aug 2026 14:47:47 -0400"
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Date: Sun, 16 Aug 2026 15:04:30 -0400
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Andrew Dunstan <andrew@dunslane.net> writes:
> On 2026-08-16 Su 1:38 PM, Tom Lane wrote:
>> The test cases I have that reach these bugs require Perl "Tie"
>> modules that aren't present in common Perl installations,
>> so I'm not planning on trying to construct regression test
>> entries for them.  But I've attached two SQL scripts that
>> cause failures without the patch.

> Which modules?

At least Tie::Array isn't present in RHEL10's standard perl
package set --- I had to install "perl-Tie" to get that test
case to run here.

>> One interesting point is that Claude Opus, which constructed
>> these test cases, seemed to think that we ought to be able
>> to read out the values assigned to the tied array or hash.
>> But what the repaired code actually produces is SQL NULLs.
>> AFAICT we are getting Perl "undef" values out of hv_iternext
>> or av_fetch, so it's hard to see how we could do any better.

> At first glance I'm inclined to agree with Opus.

If we can make it work, I'm all for that, but I wonder how many
other places have the same issue.

			regards, tom lane