Here is a tiny patch to fix $SUBJECT in a comment in execPartition.c.
diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
index 4048c3e..882b538 100644
@@ -140,10 +140,10 @@ ExecSetupPartitionTupleRouting(ModifyTableState *mtstate,
partrel = leaf_part_rri->ri_RelationDesc;
- * This is required in order to we convert the partition's
- * tuple to be compatible with the root partitioned table's
- * tuple descriptor. When generating the per-subplan result
- * rels, this was not set.
+ * This is required in order to convert the partition's tuple
+ * to be compatible with the root partitioned table's tuple
+ * descriptor. When generating the per-subplan result rels,
+ * this was not set.
leaf_part_rri->ri_PartitionRoot = rel;