diff --git a/usr.bin/kdump/kdump_subr.h b/usr.bin/kdump/kdump_subr.h
index 6e336ddbc22a..21d85a97eb24 100644
--- a/usr.bin/kdump/kdump_subr.h
+++ b/usr.bin/kdump/kdump_subr.h
@@ -45,3 +45,4 @@ void sigprocmaskhowname (int);
 void lio_listioname (int);
 void minheritname (int);
 void quotactlname (int);
+void ptraceopname (int);