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Subject: Re: [PATCH] build_bug.h: add wrapper for _Static_assert
To:     Andrew Morton <akpm@linux-foundation.org>,
        Kees Cook <keescook@chromium.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        Luc Van Oostenryck <luc.vanoostenryck@gmail.com>,
        linux-kernel@vger.kernel.org
References: <20190203192401.29170-1-linux@rasmusvillemoes.dk>
 <20190204150916.f29d782b27f096e6c4c6d6cf@linux-foundation.org>
 <20190204151209.d6fae2c6466cb5c9c5814fd9@linux-foundation.org>
From:   Rasmus Villemoes <linux@rasmusvillemoes.dk>
Message-ID: <e819dbc8-5d7a-2f7b-35c5-e70754ba28e4@rasmusvillemoes.dk>
Date:   Tue, 5 Feb 2019 10:53:31 +0100
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On 05/02/2019 00.12, Andrew Morton wrote:
>>
>> It would be (very) nice to actually use this macro in a few places so
>> it gets its build testing while in -next.
> 
> ie, just about every BUILD_BUG_ON in mm/ could use this.  Let's switch
> a few?
> 

Perhaps, but some make sense where they are, e.g. when iterating over
two arrays using one iterator variable, it's fine to assert they have
the same size just above the loop. And, unfortunately, static_assert()
is not quite a drop-in replacement for BUILD_BUG_ON even when the
argument is an ICE due to -Wdeclaration-after-statement.

I'll fix the two BUILD_BUGs I know I've added over the years (one in
vsprintf.c, one in fs/namei.c).

Rasmus