diff --git a/luisa_compute/src/runtime.rs b/luisa_compute/src/runtime.rs
index d51f7d4..33f74e5 100644
--- a/luisa_compute/src/runtime.rs
+++ b/luisa_compute/src/runtime.rs
@@ -340,9 +340,7 @@ impl Device {
             raw_window_handle::RawWindowHandle::Orbital(_) => todo!(),
             raw_window_handle::RawWindowHandle::Xlib(h) => h.window as u64,
             raw_window_handle::RawWindowHandle::Xcb(h) => h.window.get() as u64,
-            raw_window_handle::RawWindowHandle::Wayland(h) => {
-                h.surface.as_ptr() as u64
-            }
+            raw_window_handle::RawWindowHandle::Wayland(h) => h.surface.as_ptr() as u64,
             raw_window_handle::RawWindowHandle::Drm(_) => todo!(),
             raw_window_handle::RawWindowHandle::Gbm(_) => todo!(),
             raw_window_handle::RawWindowHandle::Win32(h) => h.hwnd.get() as u64,
@@ -832,6 +830,7 @@ impl Drop for SwapchainHandle {
     }
 }
 
+#[derive(Clone)]
 pub struct Swapchain {
     pub(crate) handle: Arc<SwapchainHandle>,
     #[allow(dead_code)]
diff --git a/luisa_compute_track/src/lib.rs b/luisa_compute_track/src/lib.rs
index 271664a..c2894d9 100644
--- a/luisa_compute_track/src/lib.rs
+++ b/luisa_compute_track/src/lib.rs
@@ -426,10 +426,6 @@ pub fn tracked(
     let item = syn::parse_macro_input!(item as ItemFn);
     let body = &item.block;
     let body_span = body.span();
-    let ret_type = match &item.sig.output {
-        ReturnType::Default => quote_spanned! {body_span=> () },
-        ReturnType::Type(_, ty) => quote_spanned! {body_span=> #ty },
-    };
     let body = proc_macro::TokenStream::from(quote!({ #body }));
     let body = track_impl(parse_macro_input!(body as Expr), &crate_path);
     let body = quote_spanned! {body_span=>
@@ -444,7 +440,7 @@ pub fn tracked(
             };
             #crate_path::lang::debug::comment(&format!("begin fn {} at {}:{}:{}", __fn_name, file!(), line!(), column!()));
             #[allow(clippy::let_unit_value)]
-            let __ret: #ret_type = #body;
+            let __ret = #body;
             #[allow(unreachable_code)]
             {
                 #crate_path::lang::debug::comment(&format!("end fn {} at {}:{}:{}", __fn_name, file!(), line!(), column!()));