Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Kevin Brodsky <kevin.brodsky@arm.com>
To:     linux-kernel@vger.kernel.org
Cc:     Masahiro Yamada <masahiroy@kernel.org>,
        Sam Ravnborg <sam@ravnborg.org>, linux-kbuild@vger.kernel.org,
        Kevin Brodsky <kevin.brodsky@arm.com>,
        Ruben Ayrapetyan <ruben.ayrapetyan@arm.com>
Subject: [PATCH] uapi/linux/const.h: Prefer ISO-friendly __typeof__
Date:   Thu, 19 Jan 2023 09:42:25 +0000
Message-Id: <20230119094225.2422787-1-kevin.brodsky@arm.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

typeof is (still) a GNU extension, which means that it cannot be
used when building ISO C (e.g. -std=c99). It should therefore be
avoided in uapi headers in favour of the ISO-friendly __typeof__.

Unfortunately this issue could not be detected by
CONFIG_UAPI_HEADER_TEST=y as the __ALIGN_KERNEL() macro is not
expanded in any uapi header.

Reported-by: Ruben Ayrapetyan <ruben.ayrapetyan@arm.com>
Tested-by: Ruben Ayrapetyan <ruben.ayrapetyan@arm.com>
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
---
 include/uapi/linux/const.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/linux/const.h b/include/uapi/linux/const.h
index af2a44c08683..a429381e7ca5 100644
--- a/include/uapi/linux/const.h
+++ b/include/uapi/linux/const.h
@@ -28,7 +28,7 @@
 #define _BITUL(x)	(_UL(1) << (x))
 #define _BITULL(x)	(_ULL(1) << (x))
 
-#define __ALIGN_KERNEL(x, a)		__ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
+#define __ALIGN_KERNEL(x, a)		__ALIGN_KERNEL_MASK(x, (__typeof__(x))(a) - 1)
 #define __ALIGN_KERNEL_MASK(x, mask)	(((x) + (mask)) & ~(mask))
 
 #define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
-- 
2.38.1