diff --git a/server/gameserver/airraid.cc b/server/gameserver/airraid.cc
index 49e6f7e3..cadc4305 100644
--- a/server/gameserver/airraid.cc
+++ b/server/gameserver/airraid.cc
@@ -45,22 +45,18 @@ void AirRaid::Exec(int airraid_id)
         return;
     }
 
-    auto raid_cb =
-        [this, raid_meta, center]
-        (int event, const a8::Args* args)
-        {
-            if (a8::TIMER_EXEC_EVENT != event) {
-                return;
-            }
-            if (room_->IsGameOver()) {
-                return;
-            }
-            ExecOneRoundAirRaid(raid_meta, center);
-        };
-
     room_->xtimer.SetTimeoutEx
         (SERVER_FRAME_RATE * raid_meta->appear_time() / 1000.f,
-         raid_cb,
+         [this, raid_meta, center]
+         (int event, const a8::Args* args)
+         {
+            if (a8::TIMER_EXEC_EVENT == event) {
+                if (room_->IsGameOver()) {
+                    return;
+                }
+                ExecOneRoundAirRaid(raid_meta, center);
+            }
+         },
          &room_->xtimer_attacher_);
 }