diff --git a/sys/modules/ibcs2/Makefile b/sys/modules/ibcs2/Makefile
index 9407cb40f2d0..f258fa901933 100644
--- a/sys/modules/ibcs2/Makefile
+++ b/sys/modules/ibcs2/Makefile
@@ -8,7 +8,7 @@ SRCS=	ibcs2_errno.c ibcs2_ipc.c ibcs2_stat.c ibcs2_misc.c \
 	ibcs2_socksys.c ibcs2_util.c ibcs2_xenix.c ibcs2_xenix_sysent.c \
 	ibcs2_isc.c ibcs2_isc_sysent.c \
 	ibcs2_msg.c ibcs2_other.c ibcs2_sysi86.c ibcs2_sysvec.c \
-	vnode_if.h opt_spx_hack.h
+	vnode_if.h opt_mac.h opt_spx_hack.h
 
 CFLAGS+= -DCOMPAT_IBCS2