diff --git a/sys/kern/makeobjops.pl b/sys/kern/makeobjops.pl
index 652c21b2a47..943c921ed62 100644
--- a/sys/kern/makeobjops.pl
+++ b/sys/kern/makeobjops.pl
@@ -130,6 +130,7 @@ foreach $src (@filenames) {
 	print CFILE " */\n";
 	print CFILE "\n";
 	print CFILE "#include <sys/param.h>\n";
+	print CFILE "#include <sys/cdefs.h>\n";
 	print CFILE "#include <sys/queue.h>\n";
 	print CFILE "#include <sys/kernel.h>\n";
 	print CFILE "#include <sys/kobj.h>\n";