adjust_partition_colnos mustn't be called if not needed

alvherre · alvherre · commit 183c869e1cbf · 2022-04-12T15:19:57.000+02:00
Add an assert to make this very explicit, as well as a code comment. The former should silence Coverity complaining about this. Introduced by 7103ebb. Reported-by: Ranier Vilela Discussion: https://postgr.es/m/CAEudQAqTTAOzXiYybab+1DQOb3ZUuK99=p_KD+yrRFhcDbd0jg@mail.gmail.com
diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
@@ -1530,19 +1530,25 @@ ExecBuildSlotPartitionKeyDescription(Relation rel,
  * adjust_partition_colnos
  *		Adjust the list of UPDATE target column numbers to account for
  *		attribute differences between the parent and the partition.
+ *
+ * Note: mustn't be called if no adjustment is required.
  */
 static List *
 adjust_partition_colnos(List *colnos, ResultRelInfo *leaf_part_rri)
 {
 	TupleConversionMap *map = ExecGetChildToRootMap(leaf_part_rri);
 
+	Assert(map != NULL);
+
 	return adjust_partition_colnos_using_map(colnos, map->attrMap);
 }
 
 /*
  * adjust_partition_colnos_using_map
  *		Like adjust_partition_colnos, but uses a caller-supplied map instead
  *		of assuming to map from the "root" result relation.
+ *
+ * Note: mustn't be called if no adjustment is required.
  */
 static List *
 adjust_partition_colnos_using_map(List *colnos, AttrMap *attrMap)
