diff --git a/src/backend/replication/syncrep.c b/src/backend/replication/syncrep.c
index ec594cf3df8..325239d6358 100644
--- a/src/backend/replication/syncrep.c
+++ b/src/backend/replication/syncrep.c
@@ -69,6 +69,7 @@ static int	SyncRepWaitMode = SYNC_REP_NO_WAIT;
 
 static void SyncRepQueueInsert(int mode);
 static void SyncRepCancelWait(void);
+static int	SyncRepWakeQueue(bool all, int mode);
 
 static int	SyncRepGetStandbyPriority(void);
 
@@ -546,7 +547,7 @@ SyncRepGetStandbyPriority(void)
  *
  * Must hold SyncRepLock.
  */
-int
+static int
 SyncRepWakeQueue(bool all, int mode)
 {
 	volatile WalSndCtlData *walsndctl = WalSndCtl;
diff --git a/src/include/replication/syncrep.h b/src/include/replication/syncrep.h
index b3d399dad3c..71e28578cce 100644
--- a/src/include/replication/syncrep.h
+++ b/src/include/replication/syncrep.h
@@ -47,9 +47,6 @@ extern void SyncRepReleaseWaiters(void);
 /* called by checkpointer */
 extern void SyncRepUpdateSyncStandbysDefined(void);
 
-/* called by various procs */
-extern int	SyncRepWakeQueue(bool all, int mode);
-
 /* forward declaration to avoid pulling in walsender_private.h */
 struct WalSnd;
 extern struct WalSnd *SyncRepGetSynchronousStandby(void);