diff --git a/ChangeLog b/ChangeLog
index 0fe9647..918827b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2016-06-15  Niibe Yutaka  <gniibe@fsij.org>
+
+	* chopstx.c (chopstx_exit): Add "naked" attribute.
+
 2016-06-14  Niibe Yutaka  <gniibe@fsij.org>
 
 	* mcu/usb-stm32f103.c (usb_lld_ctrl_recv): Fix the state and make
diff --git a/chopstx.c b/chopstx.c
index 5c9aed0..d27acb0 100644
--- a/chopstx.c
+++ b/chopstx.c
@@ -1502,6 +1502,12 @@ chopstx_cleanup_pop (int execute)
 }
 
 
+/*
+ *  We put "naked" attribute to chopstx_exit function.  Since it never
+ *  returns, function prologue is not needed.
+ */
+void chopstx_exit (void *retval) __attribute__ ((naked));
+
 /**
  * chopstx_exit - Terminate the execution of running thread
  * @retval: Return value (to be caught by a joining thread)