diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c
index ce511c3ed6490b..5d01db5c029e2b 100644
--- a/builtin/fsmonitor--daemon.c
+++ b/builtin/fsmonitor--daemon.c
@@ -1443,7 +1443,8 @@ static int try_to_run_foreground_daemon(int detach_console MAYBE_UNUSED)
 
 static start_bg_wait_cb bg_wait_cb;
 
-static int bg_wait_cb(const struct child_process *cp, void *cb_data)
+static int bg_wait_cb(const struct child_process *cp UNUSED,
+		      void *cb_data UNUSED)
 {
 	enum ipc_active_state s = fsmonitor_ipc__get_state();
 
diff --git a/t/helper/test-simple-ipc.c b/t/helper/test-simple-ipc.c
index 3d1436da59872f..941ae7e3bcf3ed 100644
--- a/t/helper/test-simple-ipc.c
+++ b/t/helper/test-simple-ipc.c
@@ -278,7 +278,8 @@ static int daemon__run_server(void)
 
 static start_bg_wait_cb bg_wait_cb;
 
-static int bg_wait_cb(const struct child_process *cp, void *cb_data)
+static int bg_wait_cb(const struct child_process *cp UNUSED,
+		      void *cb_data UNUSED)
 {
 	int s = ipc_get_active_state(cl_args.path);