增加宏的安全性

AWList.h

@@ -45,7 +45,7 @@ typedef struct _linked_list {
  * @param      list         List head
  */
 #define AWList_for_each(pos, list)                                             \
-	for (pos = list->head; pos != NULL; pos = pos->next)
+	for ((pos) = (list)->head->next; (pos) != NULL; (pos) = (pos)->next)
 
 /**
  * @brief      allocate memory for list