From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter@eisentraut.org>
cc: Alvaro Herrera <alvherre@alvh.no-ip.org>,
        Amit Langote <amitlangote09@gmail.com>, Erik Rijkers <er@xs4all.nl>,
        jian he <jian.universality@gmail.com>,
        Andrew Dunstan <andrew@dunslane.net>,
        PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: remaining sql/json patches
In-reply-to: <d506638e-3f5d-df45-7f11-ac797037253c@eisentraut.org>
References: <202309061501.xcwpfa2jjj5n@alvherre.pgsql>
 <d506638e-3f5d-df45-7f11-ac797037253c@eisentraut.org>
Comments: In-reply-to Peter Eisentraut <peter@eisentraut.org>
	message dated "Tue, 12 Sep 2023 09:52:50 +0200"
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Date: Tue, 12 Sep 2023 10:43:41 -0400
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Peter Eisentraut <peter@eisentraut.org> writes:
> On 06.09.23 17:01, Alvaro Herrera wrote:
>> Assert()ing that a pointer is not null, and in the next line
>> dereferencing that pointer, is useless: the process would crash anyway
>> at the time of dereference, so the Assert() adds no value.  Better to
>> leave the assert out.

> I don't think this is quite correct.  If you dereference a pointer, the 
> compiler may assume that it is not null and rearrange code accordingly. 
> So it might not crash.  Keeping the assertion would alter that assumption.

Uh ... only in assert-enabled builds.  If your claim is correct,
this'd result in different behavior in debug and production builds,
which would be even worse.  But I don't believe the claim.
I side with Alvaro's position here: such an assert is unhelpful.

			regards, tom lane