Re: Consistently use the XLogRecPtrIsInvalid() macro

Bertrand Drouvot <bertranddrouvot.pg@gmail.com>

From: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>

To: Peter Eisentraut <peter@eisentraut.org>

Cc: Álvaro Herrera <alvherre@kurilemu.de>, Michael Paquier <michael@paquier.xyz>, Heikki Linnakangas <hlinnaka@iki.fi>, Quan Zongliang <quanzongliang@yeah.net>, pgsql-hackers@lists.postgresql.org

Date: 2025-12-01T07:14:42Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Replace literal 0 with InvalidXLogRecPtr for XLogRecPtr assignments
- ec3174407164 19 (unreleased) landed
Replace pointer comparisons and assignments to literal zero with NULL
- ec782f56b0c3 19 (unreleased) landed
Use XLogRecPtrIsValid() in various places
- a2b02293bc65 19 (unreleased) landed
Introduce XLogRecPtrIsValid()
- d2965f627fe3 14.20 landed
- c0031d461324 18.1 landed
- 723cc84db50a 16.11 landed
- 49b45999f3b2 15.15 landed
- 33727aff18d0 17.7 landed
- 20bafb097288 13.23 landed
- 06edbed47862 19 (unreleased) landed

Attachments

v1-0001-Replace-pointer-comparisons-and-assignments-to-li.patch (text/x-diff)

Hi,

On Tue, Nov 18, 2025 at 04:54:32PM +0100, Peter Eisentraut wrote:
> I mean, some people like writing if (!foo) and some like writing if
> (foo == NULL), but we're not going to legislate one
> over the other.

Agree. Out of curiosity, I searched for pointers and literal zero comparisons
or assignments (with [1]) and found 6 of them.

While literal zero is technically correct, NULL is the semantically appropriate
choice for pointers.

PFA a patch to fix those 6.

[1]: https://github.com/bdrouvot/coccinelle_on_pg/blob/main/misc/pointers_and_literal_zero.cocci

Regards,

-- 
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
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