diff --git a/tinyDEMO/cmd.h b/tinyDEMO/cmd.h
index 1a20e627..fb196001 100755
--- a/tinyDEMO/cmd.h
+++ b/tinyDEMO/cmd.h
@@ -136,8 +136,8 @@ opt_t* opt_create(opt_type_t, lv_t, const char*);
 const opt_t* opt_get_by_type(const opts_L_t* , opt_type_t);
 #define opt_create_null() opt_create(opt_none, lv_none, tsk_null)
 
-const tsk_object_def_t *opt_def_t;
-const tsk_object_def_t *cmd_def_t;
+extern const tsk_object_def_t *opt_def_t;
+extern const tsk_object_def_t *cmd_def_t;
 
 _END_DECLS
 
diff --git a/tinyDEMO/common.h b/tinyDEMO/common.h
index b25dce6f..aebe6afc 100755
--- a/tinyDEMO/common.h
+++ b/tinyDEMO/common.h
@@ -116,8 +116,8 @@ int session_hangup(tsip_ssession_id_t sid);
 
 tsip_action_handle_t* action_get_config(const opts_L_t* opts);
 
-const tsk_object_def_t *session_def_t;
-const tsk_object_def_t *ctx_def_t;
+extern const tsk_object_def_t *session_def_t;
+extern const tsk_object_def_t *ctx_def_t;
 
 _END_DECLS