[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] clang -fsanitize=undefined warnings in the string visit
From: |
Paolo Bonzini |
Subject: |
Re: [Qemu-devel] clang -fsanitize=undefined warnings in the string visitors |
Date: |
Thu, 14 Jan 2016 13:44:33 +0100 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 |
On 14/01/2016 12:15, Peter Maydell wrote:
> On 5 November 2015 at 20:05, John Snow <address@hidden> wrote:
>>
>>
>> On 10/01/2015 09:38 AM, Paolo Bonzini wrote:
>>>
>>>
>>> On 01/10/2015 12:47, Peter Maydell wrote:
>>>> On 29 May 2015 at 12:12, Paolo Bonzini <address@hidden> wrote:
>>>>>
>>>>>
>>>>> On 29/05/2015 12:56, Peter Maydell wrote:
>>>>>>>>>> Paolo: ping^2, since we're out of release freeze now?
>>>>>>>>
>>>>>>>> I have some patches, but this isn't really the best time for me to post
>>>>>>>> them...
>>>>>> Ping...has the timing improved?
>>>>>
>>>>> Almost. :) Next week, promised.
>>>>
>>>> Ping again, six months later...
>>>
>>> Uh, I thought they were already in. :)
>>>
>>> Paolo
>>>
>>
>> Did patches ever get posted to list for this?
>
> Not that I saw -- ping again, Paolo. This is the only warning
> that clang's sanitizer currently produces for me, and arithmetic
> overflows on addition seem genuinely worth investigation...
It happens when the range is 2^64 in size.
Does it still matter if we've decided to use -fwrapv because of left
shifts? Or are we still considering the possibility to use -std=gnu89
(where left shifts give unspecified behavior rather than undefined)?
Paolo