[PATCH] malloc: Improve checked_request2size

[Paul Eggert]

On 6/6/25 10:31, Wilco Dijkstra wrote:
> -    return 0;
> +    return (size_t)PTRDIFF_MAX + 1;

Is there a reason this is (size_t)PTRDIFF_MAX + 1 rather than SIZE_MAX? 
If so, please comment why; if not, please change the expression to 
SIZE_MAX as that's likely to be a tad more efficient and won't leave the 
reader wondering why the code decreases the size request.