diff --git a/src/listhead.rs b/src/listhead.rs
index 58e9d0b..d2e4426 100644
--- a/src/listhead.rs
+++ b/src/listhead.rs
@@ -1,6 +1,7 @@
 use std::rc::{Rc, Weak};
 use std::cell::RefCell;
 
+#[derive(Default)]
 pub struct ListHead<T> {
     prev: Weak::<RefCell::<ListHead<T>>>,
     next: Weak::<RefCell::<ListHead<T>>>,
diff --git a/src/timer.rs b/src/timer.rs
index d80c194..b113af6 100644
--- a/src/timer.rs
+++ b/src/timer.rs
@@ -12,10 +12,12 @@ const TVR_MASK: usize = TVR_SIZE - 1;
 
 pub type TimerWp = Weak::<Rc::<RefCell::<TimerList>>>;
 
+#[derive(Default)]
 pub struct TimerAttacher {
     timers: Rc::<RefCell::<crate::ListHead<TimerAttacher>>>,
 }
 
+#[derive(Default)]
 struct TimerList {
     holder: Rc::<RefCell::<TimerList>>,
     wp: Rc::<Rc::<RefCell::<TimerList>>>,
@@ -25,7 +27,7 @@ struct TimerList {
     expire_time: i32,
     expires: i64,
 
-    cb: fn (i32, Option<Vec<Rc::<dyn Any>>>),
+    //cb: fn (i32, Option<Vec<Rc::<dyn Any>>>),
 }
 
 pub struct Timer {
@@ -73,6 +75,20 @@ impl Timer {
 
     }
 
+    fn new_timer_list(&mut self) -> Rc::<RefCell::<TimerList>> {
+        let p = Rc::new(RefCell::new(TimerList{
+            holder: Default::default(),
+            wp: Default::default(),
+            timer_entry: Default::default(),
+            attach_entry: Default::default(),
+            timer_type: 0,
+            expire_time: 0,
+            expires: 0,
+            //cb: Default::default(),
+        }));
+        return p;
+    }
+
     pub fn update(&mut self) {
 
     }