diff --git a/sys/conf/std.nodebug b/sys/conf/std.nodebug
index 6495bc0203ad..38eb77c8d3a7 100644
--- a/sys/conf/std.nodebug
+++ b/sys/conf/std.nodebug
@@ -1,27 +1,28 @@
 #
 # std.nodebug -- Disable the debug options found in the GENERIC kernel config.
 #
 
 nooptions	INVARIANTS
 nooptions	INVARIANT_SUPPORT
+nooptions	DIAGNOSTIC
 nooptions	WITNESS
 nooptions	WITNESS_SKIPSPIN
 nooptions	DEBUG_VFS_LOCKS
 nooptions	BUF_TRACKING
 nooptions	FULL_BUF_TRACKING
 nooptions	DEADLKRES
 nooptions	COVERAGE
 nooptions	KCOV
 nooptions	MALLOC_DEBUG_MAXZONES
 nooptions	QUEUE_MACRO_DEBUG_TRASH
 
 # Net80211 debugging
 nooptions	IEEE80211_DEBUG
 
 # USB debugging
 nooptions	USB_DEBUG
 nooptions	HID_DEBUG
 
 # CAM debugging
 nooptions	CAMDEBUG
 nooptions	CAM_DEBUG_FLAGS