From:   Alejandro Colomar <alx.manpages@gmail.com>
To:     LKML <linux-kernel@vger.kernel.org>
Cc:     Alejandro Colomar <alx.manpages@gmail.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Kees Cook <keescook@chromium.org>,
        Joe Perches <joe@perches.com>
Subject: [PATCH v2 07/20] linux/memberof.h: Add memberof(T, m) macro
Date:   Sat, 20 Nov 2021 14:00:50 +0100
Message-Id: <20211120130104.185699-8-alx.manpages@gmail.com>
In-Reply-To: <20211120130104.185699-1-alx.manpages@gmail.com>
References: <20211119113644.1600-1-alx.manpages@gmail.com>
 <20211120130104.185699-1-alx.manpages@gmail.com>
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Precedence: bulk

(((T *)0)->m) if a typical construct used by some wrappers,
and also directly in many places.
Write a macro to encapsulate that construct,
and avoid repetition (and possible mistakes).

It also helps readability by reducing the complexity
of mentally parsing so many symbols together,
with a readable name.

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
---
 include/linux/memberof.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)
 create mode 100644 include/linux/memberof.h

diff --git a/include/linux/memberof.h b/include/linux/memberof.h
new file mode 100644
index 000000000000..6d8cb3dabbf9
--- /dev/null
+++ b/include/linux/memberof.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_MEMBEROF_H
+#define _LINUX_MEMBEROF_H
+
+
+#include <linux/NULL.h>
+
+
+#define memberof(T, m)  (((T *)NULL)->m)
+
+
+#endif  /* _LINUX_MEMBEROF_H */
-- 
2.33.1