Define variable only in the scope that needs it

I suppose the current definition in the higher scope is not intentional. This
is what I suggest:

diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
new file mode 100644
index 9c4a1ba..ae35e1e
*** a/src/backend/optimizer/plan/planner.c
--- b/src/backend/optimizer/plan/planner.c
*************** create_ordinary_grouping_paths(PlannerIn
*** 3837,3843 ****
  {
  	Query	   *parse = root->parse;
  	Path	   *cheapest_path = input_rel->cheapest_total_path;
- 	AggClauseCosts agg_partial_costs;	/* parallel only */
  	AggClauseCosts agg_final_costs; /* parallel only */
  	double		dNumGroups;
  	bool		can_hash;
--- 3837,3842 ----
*************** create_ordinary_grouping_paths(PlannerIn
*** 3904,3909 ****
--- 3903,3909 ----
  	if (try_parallel_aggregation)
  	{
  		PathTarget *partial_grouping_target;
+ 		AggClauseCosts agg_partial_costs;	/* parallel only */

/*
* Build target list for partial aggregate paths. These paths cannot

--
Antonin Houska
Cybertec Schönig & Schönig GmbH
Gröhrmühlgasse 26, A-2700 Wiener Neustadt
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