diff --git a/util-linux/switch_root.c b/util-linux/switch_root.c
index 007083b..5a01fd6 100644
--- a/util-linux/switch_root.c
+++ b/util-linux/switch_root.c
@@ -63,6 +63,7 @@
 	} else unlink(directory);
 }
 
+int switch_root_main(int argc, char *argv[]);
 int switch_root_main(int argc, char *argv[])
 {
 	char *newroot, *console=NULL;