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Date:   Tue, 29 Jan 2019 17:36:34 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc:     Anders Roxell <anders.roxell@linaro.org>, arnd@arndb.de,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] lib/ubsan: default UBSAN_ALIGNMENT to not set
Message-Id: <20190129173634.ee579795b227b141efc8bd30@linux-foundation.org>
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References: <20181217150326.30933-1-anders.roxell@linaro.org>
        <8bc73bbf-6c12-7fd1-3253-676731bf5ae5@virtuozzo.com>
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On Fri, 11 Jan 2019 22:01:16 +0300 Andrey Ryabinin <aryabinin@virtuozzo.com> wrote:

> 
> 
> On 12/17/18 6:03 PM, Anders Roxell wrote:
> > When booting an allmodconfig kernel, there are a lot of false-positives.
> > With a message like this 'UBSAN: Undefined behaviour in...' with a call
> > trace that follows.
> > 
> > Reworked so that when building a allmodconfig kernel that turns
> > everything into '=m' or '=y' will turn off UBSAN_ALIGNMENT.
> > 
> > Suggested-by: Arnd Bergmann <arnd@arndb.de>
> > Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
> > ---
> 
> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
> 

Confused.  Why does allmodconfig result in UBSAN warnings?