diff --git a/sys/dev/sio/sio_ebus.c b/sys/dev/sio/sio_ebus.c
index 0c2e58c12d6..2a389387b99 100644
--- a/sys/dev/sio/sio_ebus.c
+++ b/sys/dev/sio/sio_ebus.c
@@ -24,7 +24,7 @@
  */
 
 #include <sys/cdefs.h>
-__FBSDID($FreeBSD$);
+__FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
 #include <sys/systm.h>