diff --git a/src/cmd/rc/rc.h b/src/cmd/rc/rc.h
index 0996eec..3e79617 100644
--- a/src/cmd/rc/rc.h
+++ b/src/cmd/rc/rc.h
@@ -9,6 +9,9 @@
 #ifdef	Plan9
 #include <u.h>
 #include <libc.h>
+#undef NSIG
+#undef SIGINT
+#undef SIGQUIT
 #define	NSIG	32
 #define	SIGINT	2
 #define	SIGQUIT	3