diff --git a/src/backend/partitioning/partprune.c b/src/backend/partitioning/partprune.c
index eae690e2ca37c..69879bf3a45a5 100644
--- a/src/backend/partitioning/partprune.c
+++ b/src/backend/partitioning/partprune.c
@@ -116,6 +116,8 @@ typedef struct PruneStepResult
 } PruneStepResult;
 
 
+static List *gen_partprune_steps(RelOptInfo *rel, List *clauses,
+					bool *contradictory);
 static List *gen_partprune_steps_internal(GeneratePruningStepsContext *context,
 							 RelOptInfo *rel, List *clauses,
 							 bool *contradictory);
@@ -355,7 +357,7 @@ make_partition_pruneinfo(PlannerInfo *root, List *partition_rels,
  * If the clauses in the input list are contradictory or there is a
  * pseudo-constant "false", *contradictory is set to true upon return.
  */
-List *
+static List *
 gen_partprune_steps(RelOptInfo *rel, List *clauses, bool *contradictory)
 {
 	GeneratePruningStepsContext context;
diff --git a/src/include/partitioning/partprune.h b/src/include/partitioning/partprune.h
index c9fe95dc30c17..3d114b4c71f74 100644
--- a/src/include/partitioning/partprune.h
+++ b/src/include/partitioning/partprune.h
@@ -67,7 +67,5 @@ extern List *make_partition_pruneinfo(PlannerInfo *root, List *partition_rels,
 extern Relids prune_append_rel_partitions(RelOptInfo *rel);
 extern Bitmapset *get_matching_partitions(PartitionPruneContext *context,
 						List *pruning_steps);
-extern List *gen_partprune_steps(RelOptInfo *rel, List *clauses,
-					bool *contradictory);
 
 #endif							/* PARTPRUNE_H */