diff --git a/lib/libsysdecode/Makefile b/lib/libsysdecode/Makefile
index b11b75a09a72..caab36d1e303 100644
--- a/lib/libsysdecode/Makefile
+++ b/lib/libsysdecode/Makefile
@@ -123,7 +123,8 @@ CFLAGS.gcc.ioctl.c+= -Wno-redundant-decls
 CFLAGS.gcc+=	${CFLAGS.gcc.${.IMPSRC}}
 
 DEPENDOBJS+=	tables.h
-tables.h: mktables
+tables.h: mktables ${SYSROOT}/sys/netinet/in.h ${SYSROOT}/sys/netinet/tcp.h \
+    ${SYSROOT}/sys/netinet6/in6.h
 	sh ${.CURDIR}/mktables ${SYSROOT:U${DESTDIR}}${INCLUDEDIR} ${.TARGET}.tmp && \
 	    mv -f ${.TARGET}.tmp ${.TARGET}