Re: [PATCH v2 5/8] c: Do not ignore some forms of -Wimplicit-int in system headers

[Sam James <sam@gentoo.org>]

Florian Weimer <fweimer@redhat.com> writes:

> * Sam James:
>
>> Florian Weimer <fweimer@redhat.com> writes:
>>
>>> Most -Wimplicit-int warnings were unconditionally disabled for system
>>> headers.  Only missing types for parameters in old-style function
>>> definitions resulted in warnings.  This is inconsistent with the
>>> treatment of other permerrors, which are active in system headers.
>>
>> The situation with system headers is kind of a mess still. I went
>> looking for a bug for the -Wimplicit-int behaviour but I only found
>> PR78000 for -Wimplicit-function-declaration. But in the bug, Joseph
>> makes the same observation.
>>
>> I don't suppose he'll want to block on that at this late point though.
>>
>> Do you know offhand what Clang's behaviour is wrt warnings in system
>> headers?
>
> Clang ignores these new errors in system headers by default.  I don't
> know if that's deliberate or a bug.  Our permerrors are deliberately
> active in system headers.  As the test shows, -Wimplicit-int really was
> the outlier here because of that check outside the permerror machinery.

Thanks - my assumption was that it was more widespread because of a few
lingering bugs I've seen a few projects complain about, but maybe they
were using old versions or similar.

>
> I expect system headers are quite clean actually because they have to be
> for C++ compatibility.  Some things have improved in the last 25 years.
>

Oh, duh. Thank you!