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Date:   Thu, 14 May 2020 14:27:35 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Will Deacon <will@kernel.org>
Cc:     Marco Elver <elver@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Dmitry Vyukov <dvyukov@google.com>
Subject: Re: [PATCH v5 00/18] Rework READ_ONCE() to improve codegen
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On Thu, May 14, 2020 at 01:01:04PM +0100, Will Deacon wrote:

> > +#if __has_feature(undefined_sanitizer)
> 
> Hmm, this might want to be __has_feature(undefined_behavior_sanitizer)
> (and damn is that hard for a Brit to type out!)

(I know right, it should be behaviour, dammit!)

I tried without the condition, eg.:

+#define __no_sanitize_undefined \
+               __attribute__((no_sanitize("undefined")))

and it still generated UBSAN gunk.