Thread

1. Remove unneccessary memory initialization in planner.c

   Chao Li <li.evan.chao@gmail.com> — 2025-12-08T11:10:58Z

   Hi Hackers,
   
   In this code piece:
   ```
   static grouping_sets_data *
   preprocess_grouping_sets(PlannerInfo *root)
   {
   ...
   grouping_sets_data *gd = palloc0(sizeof(grouping_sets_data));
   ...
   gd->any_hashable = false;
   gd->unhashable_refs = NULL;
   gd->unsortable_refs = NULL;
   gd->unsortable_sets = NIL;
   ...
   ```
   
   "gd" is allocated by palloc0, so all members have been zero initialized,
   thus explicitly assigning NULL to the 4 members is unnecessary. I don't
   think that has much runtime impact, but from a readability perspective, a
   potential question is that, "gd" has more fields, why only set 0 to these 4
   members redundantly?
   
   To avoid the potential confusion, I think we'd better delete these
   initializations.
   
   Begards,
   Chao Li (Evan)
   ---------------------
   HighGo Software Co., Ltd.
   https://www.highgo.com/
   

2. Re: Remove unneccessary memory initialization in planner.c

   Aleksander Alekseev <aleksander@tigerdata.com> — 2025-12-08T12:17:25Z

   Hi Chao,
   
   > "gd" is allocated by palloc0, so all members have been zero initialized, thus explicitly assigning NULL to the 4 members is unnecessary. I don't think that has much runtime impact, but from a readability perspective, a potential question is that, "gd" has more fields, why only set 0 to these 4 members redundantly?
   >
   > To avoid the potential confusion, I think we'd better delete these initializations.
   
   Good find. I agree that this code is redundant. Or alternatively we
   should do palloc() and assign all the initial values explicitly.
   
   -- 
   Best regards,
   Aleksander Alekseev