From ad9aa0685925a1297fc7683e2a178dec419fe3e6 Mon Sep 17 00:00:00 2001
From: Mark Johnston <markj@FreeBSD.org>
Date: Sat, 9 Mar 2024 00:08:43 -0500
Subject: [PATCH] ktrace: Add __ktrace_used

This suppresses warnings about write-only variables when the KTRACE
option is disabled, akin __diagused and __witness_used.

MFC after:	1 week

(cherry picked from commit cce4979133ba540ca2dfd57631c6f91673b9bafd)
---
 sys/sys/ktrace.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sys/sys/ktrace.h b/sys/sys/ktrace.h
index 110e1469857..594f912b02e 100644
--- a/sys/sys/ktrace.h
+++ b/sys/sys/ktrace.h
@@ -336,8 +336,10 @@ void	ktrcapfail(enum ktr_cap_fail_type, const cap_rights_t *,
 extern u_int ktr_geniosize;
 #ifdef	KTRACE
 extern int ktr_filesize_limit_signal;
+#define	__ktrace_used
 #else
 #define	ktr_filesize_limit_signal 0
+#define	__ktrace_used	__unused
 #endif
 #else