diff --git a/extra/io/serial/unix/termios/bsd/bsd.factor b/extra/io/serial/unix/termios/bsd/bsd.factor
index 1d1e217ba0..1727861269 100644
--- a/extra/io/serial/unix/termios/bsd/bsd.factor
+++ b/extra/io/serial/unix/termios/bsd/bsd.factor
@@ -1,6 +1,7 @@
 ! Copyright (C) 2008 Doug Coleman.
 ! See http://factorcode.org/license.txt for BSD license.
-USING: alien.syntax classes.struct kernel sequences system ;
+USING: alien.c-types alien.syntax classes.struct kernel
+sequences system ;
 IN: io.serial.unix.termios
 
 CONSTANT: NCCS 20