diff --git a/src/include/utils/acl.h b/src/include/utils/acl.h
index 0278d1e6a52..4f2a3c59904 100644
--- a/src/include/utils/acl.h
+++ b/src/include/utils/acl.h
@@ -230,7 +230,7 @@ extern void select_best_grantor(const RoleSpec *grantedBy, AclMode privileges,
 								Oid *grantorId, AclMode *grantOptions);
 
 /* DATABASEOID syscache hash value for our own database, set by initialize_acl */
-extern uint32 cached_db_hash;
+extern PGDLLIMPORT uint32 cached_db_hash;
 
 extern void initialize_acl(void);