diff --git a/c_src/bdberl_tpool.c b/c_src/bdberl_tpool.c
index 41156cd..4411173 100644
--- a/c_src/bdberl_tpool.c
+++ b/c_src/bdberl_tpool.c
@@ -45,8 +45,9 @@ static int remove_pending_job(TPool* tpool, TPoolJob* job);
 static void cleanup_job(TPool* tpool, TPoolJob* job);
 static int is_active_job(TPool* tpool, TPoolJob* job);
 
-#define LOCK(t) erl_drv_mutex_lock(tpool->lock)
-#define UNLOCK(t) erl_drv_mutex_unlock(tpool->lock)
+#define LOCK(tpool) erl_drv_mutex_lock(tpool->lock)
+#define UNLOCK(tpool) erl_drv_mutex_unlock(tpool->lock)
+
 
 TPool* bdberl_tpool_start(unsigned int thread_count)
 {