diff --git a/sys/sparc64/include/clock.h b/sys/sparc64/include/clock.h
index b0e4c0b06d0..c98b024437e 100644
--- a/sys/sparc64/include/clock.h
+++ b/sys/sparc64/include/clock.h
@@ -33,4 +33,6 @@ extern u_long tick_increment;
 extern u_long tick_freq;
 extern u_long tick_MHz;
 
+int	sysbeep(int, int);
+
 #endif /* !_MACHINE_CLOCK_H_ */