--- mirrormagic-2.0.2.0deb1.orig/src/main.h
+++ mirrormagic-2.0.2.0deb1/src/main.h
@@ -459,7 +459,9 @@
 #endif
 extern struct HiScore		highscore[];
 extern struct TapeInfo		tape;
-extern struct JoystickInfo	joystick[];
+// this joystick array is not used, and interferes with amd64 compilation under
+// gcc4, so comment it out.
+//extern struct JoystickInfo	joystick[];
 extern struct SetupInfo		setup;
 extern struct GameInfo		game;
 extern struct LaserInfo		laser;