diff --git a/src/tests/suite/daos_base_tx.c b/src/tests/suite/daos_base_tx.c
index 0c6bd80d71c..db1b8107f60 100644
--- a/src/tests/suite/daos_base_tx.c
+++ b/src/tests/suite/daos_base_tx.c
@@ -9,6 +9,9 @@
  *
  * tests/suite/daos_base_tx.c
  */
+
+/* only for test */
+
 #define D_LOGFAC	DD_FAC(tests)
 
 #include "daos_test.h"