Re: Consistently use palloc_object() and palloc_array()

David Geier <geidav.pg@gmail.com>

From: David Geier <geidav.pg@gmail.com>

To: Chao Li <li.evan.chao@gmail.com>

Cc: pgsql-hackers <pgsql-hackers@postgresql.org>

Date: 2025-11-28T21:06:34Z

Lists: pgsql-hackers

Commits

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btree_gist: Fix memory allocation formula
- 5cf03552fbb4 19 (unreleased) landed
Use palloc_object() and palloc_array(), the last change
- 4f7dacc5b82a 19 (unreleased) landed
pg_buffercache: Fix memory allocation formula
- 580b5c2f397f 18.2 landed
- 3f83de20ba2e 19 (unreleased) landed
Fix allocation formula in llvmjit_expr.c
- 0c67dbcc4e39 14.21 landed
- 07ddf6197b78 15.16 landed
- 5a4dc4aabd03 16.12 landed
- 0bab0c3b74af 17.8 landed
- 5b7bbf16db34 18.2 landed
- 06761b6096b6 19 (unreleased) landed
Use palloc_object() and palloc_array() in backend code
- 1b105f9472bd 19 (unreleased) landed
Use palloc_object() and palloc_array() in more areas of the tree
- 0c3c5c3b06a3 19 (unreleased) landed
Use more palloc_object() and palloc_array() in contrib/
- 31d3847a37be 19 (unreleased) landed

Hi!

Thanks for taking a look.

On 27.11.2025 00:03, Chao Li wrote:
> 
> This is a large patch, I just take a quick look, and found that:
> 
> ```
> -		*phoned_word = palloc(sizeof(char) * strlen(word) + 1);
> +		*phoned_word = palloc_array(char, strlen(word) + 1);
> ```
> 
> And
> 
> ```
> -		params = (const char **) palloc(sizeof(char *));
> +		params = palloc_object(const char *);
> ```
> 
> Applying palloc_array and palloc_object to char type doesn’t seem to improve anything.
> 

You mean because sizeof(char) is always 1 and hence we could instead
simply write:

*phoned_word = palloc(strlen(word) + 1);
params = palloc(1);

I think the _array and _object variants are more expressive and for sure
don't make the code less readable.

--
David Geier