diff --git a/lib/locking/cluster_locking.c b/lib/locking/cluster_locking.c
index 89d7307e6..7cbb8f185 100644
--- a/lib/locking/cluster_locking.c
+++ b/lib/locking/cluster_locking.c
@@ -33,7 +33,7 @@
 #include <unistd.h>
 
 #ifndef CLUSTER_LOCKING_INTERNAL
-int lock_resource(struct cmd_context *cmd, const char *resource, uint32_t flags);
+int lock_resource(struct cmd_context *cmd, const char *resource, uint32_t flags, struct logical_volume *lv __attribute__((unused)));
 int query_resource(const char *resource, int *mode);
 void locking_end(void);
 int locking_init(int type, struct dm_config_tree *cf, uint32_t *flags);