diff --git a/stand/powerpc/ofw/start.c b/stand/powerpc/ofw/start.c
index 911a2ec2af77..5e0744be45a3 100644
--- a/stand/powerpc/ofw/start.c
+++ b/stand/powerpc/ofw/start.c
@@ -67,6 +67,8 @@ _start:				\n\
 2:	b	startup		\n\
 ");
 
+void main(int (*openfirm)(void *));
+
 void
 startup(void *vpd, int res, int (*openfirm)(void *), char *arg, int argl)
 {