diff --git a/sys/conf/kern.mk b/sys/conf/kern.mk
--- a/sys/conf/kern.mk
+++ b/sys/conf/kern.mk
@@ -48,9 +48,8 @@
 CWARNEXTRA+=	-Wno-address-of-packed-member
 .if ${COMPILER_VERSION} >= 150000
 # Clang 15 has much more aggressive diagnostics about
-# mismatched prototypes and unused-but-set variables. Make these
+# unused-but-set variables. Make these
 # non-fatal for the time being.
-CWARNEXTRA+=	-Wno-error=strict-prototypes
 CWARNEXTRA+=	-Wno-error=unused-but-set-variable
 .endif
 .endif	# clang