Re: Consistently use palloc_object() and palloc_array()

Hi Michael!

On 27.11.2025 01:24, Michael Paquier wrote:
> On Wed, Nov 26, 2025 at 11:09:31PM +0100, David Geier wrote:
>> I've changed all code to use the "new" palloc_object(), palloc_array(),
>> palloc0_object(), palloc0_array, repalloc_array() and repalloc0_array()
>> macros. This makes the code more readable and more consistent.
>>
>> The patch is pretty big but potential merge conflicts should be easy to
>> resolve. If preferred, I can also further split up the patch, e.g.
>> directory by directory or high impact files first.
>
> The backpatching extra-pain argument indeed comes into mind first when
> it comes to such changes, but perhaps we should just bite the bullet
> and encourage the new allocation styles across the tree, as you are
> doing here. I'm not completely sure if it would make sense to split
> things up, if we do I would do it on a subdirectory basis like to
> suggest, perhaps, like contrib/, src/backend/executor/, etc. to
> balance the blast damage. Did you use some kind of automation to find
> all of these? If yes, what did you use?
I thought again about splitting up the patch. I'm not sure how useful
this really is. If a single committer takes this on, then it doesn't
really matter. He can apply the patch but then commit directory by
directory or in any other way he deems best. If we want to divide the
work among multiple committers splitting might be more useful.

Just tell me what you prefer and I'll provide the patch accordingly.

>> The patch is passing "meson test" and I've additionally wrote a script
>> that parses the patch file and verifies that every two corresponding +
>> and - lines match (e.g. palloc0() replaced by palloc0_array() or
>> palloc0_object(), the same for palloc() and repalloc(), additionally
>> some checks to make sure the conversion to the _array() variant is
>> correct).
>
> It may be an idea to share that as well, so as your checks could be
> replicated rather than partially re-guessed.
I've attached the script. You can run it via

python3 verify_palloc_pairs.py patch_file

Disclaimer: The script is a bit of a mess. It doesn't check repalloc()
and it still reports five conversions as erroneous while they're
actually correct. I checked them manually. I left it at that because the
vast majority of changes it processes correctly and all tests pass. The
repalloc() occurrences I also checked manually.

--
David Geier