diff --git a/sbin/newfs_msdos/Makefile b/sbin/newfs_msdos/Makefile
index cdfd3a86aa0f..da8f230090e5 100644
--- a/sbin/newfs_msdos/Makefile
+++ b/sbin/newfs_msdos/Makefile
@@ -3,4 +3,8 @@
 PROG=	newfs_msdos
 MAN8=	newfs_msdos.8
 
+.if ${MACHINE} == "pc98"
+CFLAGS+= -DPC98
+.endif
+
 .include <bsd.prog.mk>