diff --git a/Foundation/include/Poco/AbstractDelegate.h b/Foundation/include/Poco/AbstractDelegate.h
index 510f381ae..a4e8b3c4c 100644
--- a/Foundation/include/Poco/AbstractDelegate.h
+++ b/Foundation/include/Poco/AbstractDelegate.h
@@ -55,7 +55,7 @@ public:
 	{
 	}
 
-	AbstractDelegate(const AbstractDelegate& del)
+	AbstractDelegate(const AbstractDelegate& /*del*/)
 	{
 	}