RE: [PoC] pg_upgrade: allow to upgrade publisher node

Dear Amit,

> +int
> +count_old_cluster_logical_slots(void)
> +{
> + int dbnum;
> + int slot_count = 0;
> +
> + for (dbnum = 0; dbnum < old_cluster.dbarr.ndbs; dbnum++)
> + slot_count += old_cluster.dbarr.dbs[dbnum].slot_arr.nslots;
> +
> + return slot_count;
> +}
> 
> In this code, aren't we assuming that 'slot_arr.nslots' will be zero
> for versions <=PG16? On my Windows machine, this value is not zero but
> rather some uninitialized negative value which makes its caller try to
> allocate some undefined memory and fail. I think you need to
> initialize this in get_old_cluster_logical_slot_infos() for lower
> versions.

Good catch, I could not notice because it worked well in my RHEL. Here is the
updated version.

Best Regards,
Hayato Kuroda
FUJITSU LIMITED