diff --git a/include/rtdef.h b/include/rtdef.h
index 77c302dffa..9c6cd8207f 100644
--- a/include/rtdef.h
+++ b/include/rtdef.h
@@ -110,7 +110,7 @@ typedef rt_base_t                       rt_off_t;       /**< Type for offset */
     #include <stdarg.h>
     #define SECTION(x)                  @ x
     #define RT_UNUSED
-    #define RT_USED
+    #define RT_USED                     __root
     #define PRAGMA(x)                   _Pragma(#x)
     #define ALIGN(n)                    PRAGMA(data_alignment=n)
     #define WEAK                        __weak