Re: Mark function arguments of type "T *" as "const T *" where possible

From: Jacob Champion <jacob(dot)champion(at)enterprisedb(dot)com>
To: Bertrand Drouvot <bertranddrouvot(dot)pg(at)gmail(dot)com>
Cc: pgsql-hackers(at)lists(dot)postgresql(dot)org
Subject: Re: Mark function arguments of type "T *" as "const T *" where possible
Date: 2025-12-11 17:51:49
Message-ID: CAOYmi+=+LKvTwsPMYfLL0JE3zs=hK+BHtn6DzifeQhOe3R4NCQ@mail.gmail.com
Views: Whole Thread | Raw Message | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Wed, Dec 10, 2025 at 11:22 PM Bertrand Drouvot
<bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
> Also, with the patch in place that would mean "think twice before changing
> from const to no const" and that could create doubts and waste of time for future
> patch authors.

Yeah, exactly.

> Let me try to focus on functions that really
> deserve the change. I could look at function names that contain "copy" or "cmp",
> functions that are used for formatting/printing and size/length calculations as
> examples.

Sure, that sounds reasonable, and I would hope that those sorts of
functions are not very high on the list of backport contention.

> Any other ideas?

Just that the most useful const additions (IMHO) are going to be
places at the top of a big hierarchy, where callers expect something
not to be modified, but the lowest levels are too far removed from
that expectation for developers to easily remember. I imagine those
cases are not going to be easy to find automatically (but that
shouldn't discourage incremental improvements that can be found that
way).

Thanks!
--Jacob

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Daniel Gustafsson 2025-12-11 17:51:53 Re: Serverside SNI support in libpq
Previous Message Andres Freund 2025-12-11 17:49:21 Re: [PATCH] Fix severe performance regression with gettext 0.20+ on Windows