Index: sysutils/lsof/files/patch-dialects-freebsd-dlsof.h
===================================================================
--- /dev/null
+++ sysutils/lsof/files/patch-dialects-freebsd-dlsof.h
@@ -0,0 +1,16 @@
+--- dialects/freebsd/dlsof.h.orig	2019-05-08 07:32:25 UTC
++++ dialects/freebsd/dlsof.h
+@@ -45,6 +45,13 @@
+ #include <signal.h>
+ #include <unistd.h>
+ 
++#if	FREEBSDV>=13000
++/* This header is a huge mess.  Please don't support EOL FreeBSD releases. */
++#define	_KERNEL	1
++#include <sys/_lock.h>
++#undef	_KERNEL
++#endif		/* FREEBSDV>=13000 */
++
+ # if	FREEBSDV>=4000
+ #  if	FREEBSDV>=5000
+ #   if	FREEBSDV<6020