diff --git a/stand/i386/zfsboot/zfsboot.c b/stand/i386/zfsboot/zfsboot.c
index ed791f14a1f3..1067c4c6cd42 100644
--- a/stand/i386/zfsboot/zfsboot.c
+++ b/stand/i386/zfsboot/zfsboot.c
@@ -161,6 +161,8 @@ ptov(uintptr_t x)
 	return (PTOV(x));
 }
 
+int main(void);
+
 int
 main(void)
 {