diff --git a/usr.bin/kdump/mkioctls b/usr.bin/kdump/mkioctls
index 893492d96cf..50f0fdec948 100644
--- a/usr.bin/kdump/mkioctls
+++ b/usr.bin/kdump/mkioctls
@@ -35,6 +35,7 @@ BEGIN {
 	print "#include <netatm/atm_sap.h>"
 	print "#include <netatm/atm_sys.h>"
 	print "#include <netinet/in.h>"
+	print "#include <netinet/ip_mroute.h>"
 	print "#include <cam/cam.h>"
 	print "#include <stdio.h>"
 	print ""