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Re: [RFC v5 01/21] sunrpc/clnt_udp: Ensure total_deadline is initalised
- From: Jeff Law <law at redhat dot com>
- To: Alistair Francis <alistair23 at gmail dot com>, Joseph Myers <joseph at codesourcery dot com>
- Cc: Zack Weinberg <zackw at panix dot com>, Alistair Francis <alistair dot francis at wdc dot com>, GNU C Library <libc-alpha at sourceware dot org>, Arnd Bergmann <arnd at arndb dot de>, Adhemerval Zanella <adhemerval dot zanella at linaro dot org>, Florian Weimer <fweimer at redhat dot com>, Palmer Dabbelt <palmer at sifive dot com>, macro at wdc dot com, Zong Li <zongbox at gmail dot com>
- Date: Thu, 5 Sep 2019 19:31:26 -0600
- Subject: Re: [RFC v5 01/21] sunrpc/clnt_udp: Ensure total_deadline is initalised
- References: <cover.1567097252.git.alistair.francis@wdc.com> <871316fb87a99a59c31e6d3fbd4d35bff2ecc3c4.1567097252.git.alistair.francis@wdc.com> <alpine.DEB.2.21.1908291721250.4240@digraph.polyomino.org.uk> <CAKCAbMjmQaFTJ3NskTttrVPoSb-OmLJok1+Qe5hwaXa3VSpwXg@mail.gmail.com> <CAKmqyKMTG8kWkjJ2+OWY3kxOch45Qg4sVfcfA719djCfyrGuWg@mail.gmail.com> <alpine.DEB.2.21.1909051458000.25305@digraph.polyomino.org.uk> <CAKmqyKP1jPnNvPdoq1dqK8P8=gqe2Ygxkh-Mm0cH9v88xmHCyw@mail.gmail.com>
On 9/5/19 6:46 PM, Alistair Francis wrote:
> On Thu, Sep 5, 2019 at 8:02 AM Joseph Myers <joseph@codesourcery.com> wrote:
>>
>> On Thu, 5 Sep 2019, Alistair Francis wrote:
>>
>>> On Thu, Aug 29, 2019 at 10:34 AM Zack Weinberg <zackw@panix.com> wrote:
>>>>
>>>> On Thu, Aug 29, 2019 at 1:22 PM Joseph Myers <joseph@codesourcery.com> wrote:
>>>>> On Thu, 29 Aug 2019, Alistair Francis wrote:
>>>>> The long pole is definitely the ml2014 build environment, unless for some reason we need the new version of pip first? I don't actually know. I'm assu
>>>>>> Even though total_deadline won't be accessed uninitalised GCC can still
>>>>>> complain that it is accessed unitalised, to avod those errors let's make
>>>>>> sure we initalise it to 0.
>>>>>
>>>>> It's glibc practice (although missing from
>>>>> <https://sourceware.org/glibc/wiki/Style_and_Conventions>) that we *don't*
>>>>> add initializations like that to avoid warnings.
>>>>
>>>> Although this has historically been glibc practice, I think it is
>>>> unwisely incautious, and we should change the policy to be that we
>>>> *do* add initializations whenever the compiler thinks a variable even
>>>> _might_ be used uninitialized.
>>>
>>> Does that mean this patch is ok?
>>
>> No. You can't deduce consensus like that from two different views on a
>> patch or a convention. Even if we were to change the convention regarding
>> how to silence such warnings, I see reason to have any less requirement
>> for comments explaining why the warning is a false positive and that the
>> initializer is only there to silence a warning than there is for the
>> DIAG_* macros.
>
> No worries, I'll happily change the patch, I just want to make sure I
> change it to the right thing.
>
> I'll:
> - Investigate filing a GCC bug for this false positive
All we need is the .i file (Add -save-temps to the compilation line), a
copy of the full compilation line and the target triplet. No need to
try and create a minimal testcase or anything like that.
Jeff