From ec41a96daaa6e401bc0d4ba71d9cf37a1d79fc86 Mon Sep 17 00:00:00 2001
From: John Baldwin <jhb@FreeBSD.org>
Date: Sat, 1 Jul 2023 12:21:13 -0700
Subject: [PATCH] sys: Switch the kernel's C standard from C99 to GNU99.

This matches the default used in userland, and the kernel already
depends on various GNU extensions to standard C that are supported by
both clang and GCC.

This should be a no-op for clang, but for GCC it enables some GNU
extensions that aren't otherwise enabled.  It also enables GCC for
i386 to avoid the need for a floatundidf intrinsic in libkern.

Reviewed by:	imp
Differential Revision:	https://reviews.freebsd.org/D40646
---
 sys/conf/kern.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/conf/kern.mk b/sys/conf/kern.mk
index 9e977a6e4a01..51bbfcbaa617 100644
--- a/sys/conf/kern.mk
+++ b/sys/conf/kern.mk
@@ -278,7 +278,7 @@ PHONY_NOTMAIN = afterdepend afterinstall all beforedepend beforeinstall \
 .PHONY: ${PHONY_NOTMAIN}
 .NOTMAIN: ${PHONY_NOTMAIN}
 
-CSTD=		c99
+CSTD=		gnu99
 
 .if ${CSTD} == "k&r"
 CFLAGS+=        -traditional