Re: [PATCH] strbuf: stop out-of-boundary warnings from Coverity

From: Stefan Beller <sbeller@google.com>
Date: Jun 17, 2015, 20:03 UTC
Message-ID: <CAGZ79kZCGck24KZBhVa9TGtR4U6Moz-vHNrBMk0HLTz6YeHhsg@mail.gmail.com>
In-Reply-To: <20150617191235.GB25304@peff.net>

On Wed, Jun 17, 2015 at 12:12 PM, Jeff King <peff@peff.net> wrote:

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> On Wed, Jun 17, 2015 at 10:58:10AM -0700, Stefan Beller wrote:
>
>> > Just make strbuf_slopbuf[] large enough to keep Coverity happy. If it's
>> > happy, we'll have cleaner defect list
>>
>> It's down 31 defects, roughly 10% of all things coverity detected as
>> problematic.
>> YAY!
>
> That's a good thing.  I do find the solution a little gross, though. I
> wonder if there is a way we can tell coverity more about how strbuf
> works.

I always thought the problem was a combination of both having a custom strcmp (like skip_prefix, starts_with) and a custom data structure (strbuf, string_list). So I am not sure if it is sufficient to tell coverity

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> I've noticed similar problems with string_list, where it
> complains that we are touching list->items, which was assigned to NULL
> (of course it was, but then after that we did string_list_append!).
>
> I know literally nothing about coverity's annotations and what's
> possible with them. So I may be barking up a wrong tree completely.

I have searched for the exact annotations for a while, but all I found were examples in other open source projects, no official documentation with all its features. I may be missing something though (there must be some official documentation, I'd assume).

>
> -Peff