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Date:   Tue, 23 Aug 2022 20:46:23 -0700
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Subject: Re: [for-linus][PATCH 01/10] tracing: Suppress sparse warnings
 triggered by is_signed_type()
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To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Hellwig <hch@lst.de>,
        Luc Van Oostenryck <luc.vanoostenryck@gmail.com>,
        Jens Axboe <axboe@kernel.dk>
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From:   Bart Van Assche <bvanassche@acm.org>
In-Reply-To: <CAHk-=wgV1F7_ErXkXT2wd+07LJd_3Vp-yVUKLROPiEgijeoTrQ@mail.gmail.com>
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On 8/23/22 18:49, Linus Torvalds wrote:
> That's the
> 
>> It does require that kernel change to make
>>
>>    #define is_signed_type(type)   (((type)(-1)) <= (type)0)
> 
> part I was talking about.
> 
> So your kernel side patch looks fine, except I don't think you need
> the '__force' - the sparse patches in my tree should make sparse happy
> about casting '-1'.

Thank you for having provided this feedback. If I change the
is_signed_type() definition into the above (no __force), the sparse
warnings shown in my previous email disappear. Now I'm puzzled about
how this is possible. I guess I should take a closer look at the sparse
patches.

Bart.