--- cppconn/warning.h
+++ cppconn/warning.h
@@ -59,7 +59,7 @@
 
 	virtual ~SQLWarning(){};
 
-	SQLWarning(const SQLWarning& e){};
+	SQLWarning(const SQLWarning&){};
 
 private:
 	const SQLWarning & operator = (const SQLWarning & rhs);