diff --git a/signal.hpp b/signal.hpp
index fe397299..62749a6d 100644
--- a/signal.hpp
+++ b/signal.hpp
@@ -114,6 +114,14 @@ namespace cruft {
 
         public:
             signal () = default;
+
+            signal (signal const&) = default;
+            signal& operator= (signal const&) = default;
+
+            signal (signal &&) noexcept = default;
+            signal& operator= (signal &&) noexcept = default;
+
+
             ~signal ()
             {
                 CHECK (empty ());