trying to fix undo bug

project/effect.cpp

@@ -28,9 +28,9 @@ void Effect::field_changed() {
 	panel_viewer->viewer_widget->update();
 }
 
-Effect* Effect::copy() {return NULL;}
-void Effect::load(QXmlStreamReader* stream) {}
-void Effect::save(QXmlStreamWriter *stream) {}
+Effect* Effect::copy(Clip*) {return NULL;}
+void Effect::load(QXmlStreamReader*) {}
+void Effect::save(QXmlStreamWriter*) {}
 
 void Effect::process_gl(int*, int*) {}
 void Effect::process_audio(uint8_t*, int) {}