diff --git a/sys/modules/usb/ucom/Makefile b/sys/modules/usb/ucom/Makefile
index bda903c94b1c..b7836a83aab3 100644
--- a/sys/modules/usb/ucom/Makefile
+++ b/sys/modules/usb/ucom/Makefile
@@ -30,7 +30,7 @@ S=     ${.CURDIR}/../../..
 .PATH: $S/dev/usb/serial
 
 KMOD=	ucom
-SRCS=	opt_bus.h opt_usb.h device_if.h bus_if.h usb_if.h usbdevs.h \
+SRCS=	opt_bus.h opt_usb.h opt_gdb.h device_if.h bus_if.h usb_if.h usbdevs.h \
 	usb_serial.c
 
 .include <bsd.kmod.mk>