diff --git a/include/syscall.h b/include/syscall.h
index 2e740f62ea09f7809b23d2896b4b86ba2d2edc77..bd5eceadc9a5281516ece1c7a5e77c53b3efa696 100644
--- a/include/syscall.h
+++ b/include/syscall.h
@@ -18,11 +18,11 @@ void Pass();
 
 void Exit();
 
-int Send (int TaskID, void* Msg, int MsgLen, void* Reply, int ReplyLen) {};
+int Send (int TaskID, void* Msg, int MsgLen, void* Reply, int ReplyLen);
 
-int Receive (int TaskID, void* Msg, int MsgLen) {};
+int Receive (int TaskID, void* Msg, int MsgLen);
 
-int Reply (int TaskID, void* Reply, int ReplyLen) {};
+int Reply (int TaskID, void* Reply, int ReplyLen);
 
 
 #endif