Re: [PATCH] pedantic warning behavior when casting void* to ptr-to-func, 4.8 and 4.9

[Daniel Gutson <daniel dot gutson at tallertechnologies dot com>]

Sorry, ping for maintainer.

We'd do need this for 4.8.3.

Thanks,

    Daniel.

On Tue, Apr 22, 2014 at 9:15 AM, Daniel Gutson
<daniel.gutson@tallertechnologies.com> wrote:
> Ping for maintainer please.
>
> Thanks,
>
>    Daniel.
>
> On Tue, Apr 15, 2014 at 7:05 PM, Daniel Gutson
> <daniel.gutson@tallertechnologies.com> wrote:
>> On Tue, Apr 15, 2014 at 6:12 PM, Richard Sandiford
>> <rdsandiford@googlemail.com> wrote:
>>> cc:ing Jason, who's the C++ maintainer.
>>
>>
>> FWIW: I created http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60850
>>
>>>
>>> Daniel Gutson <daniel.gutson@tallertechnologies.com> writes:
>>>> ping for maintainer.
>>>>
>>>> Could this be considered for 4.8.3 please?
>>>>
>>>> Thanks,
>>>>
>>>>    Daniel.
>>>>
>>>>
>>>> On Tue, Apr 1, 2014 at 2:46 PM, Daniel Gutson
>>>> <daniel.gutson@tallertechnologies.com> wrote:
>>>>>
>>>>> I just realized I posted the patch in the wrong list.
>>>>>
>>>>>
>>>>> ---------- Forwarded message ----------
>>>>> From: Daniel Gutson <daniel.gutson@tallertechnologies.com>
>>>>> Date: Tue, Apr 1, 2014 at 10:43 AM
>>>>> Subject: [PATCH] pedantic warning behavior when casting void* to
>>>>> ptr-to-func, 4.8 and 4.9
>>>>> To: gcc Mailing List <gcc@gcc.gnu.org>
>>>>>
>>>>>
>>>>> Hi,
>>>>>
>>>>>    I observed two different behaviors in gcc 4.8.2 and 4.9 regarding
>>>>> the same issue, IMO both erroneous.
>>>>>
>>>>> Regarding 4.8.2, #pragma GCC diagnostic ignored "-pedantic" doesn't
>>>>> work in cases such as:
>>>>>     void* p = 0;
>>>>> #pragma GCC diagnostic ignored "-pedantic"
>>>>>     F* f2 = reinterpret_cast<F*>(p);
>>>>>
>>>>> (see testcase in the patch).
>>>>>
>>>>> The attached patch attempts to fix this issue. Since I no longer have
>>>>> write access, please
>>>>> apply this for me if correct (is the 4.8 branch still alive for adding fixes?).
>>>>>
>>>>> Regarding 4.9, gcc fails to complain at all when -pedantic is passed,
>>>>> even specifying -std=c++03.
>>>>> Please let me know if this is truly a bug, in which case I could also
>>>>> fix it for the latest version as well
>>>>> (if so, please let me know if I should look into trunk or any other branch).
>>>>>
>>>>> Thanks,
>>>>>
>>>>>    Daniel.
>>>>>
>>>>> 2014-03-31  Daniel Gutson  <daniel.gutson@tallertechnologies.com>
>>>>>
>>>>> gcc/cp/
>>>>>         * typeck.c (build_reinterpret_cast_1): Pass proper argument to
>>>>> warn() in pedantic.
>>>>>
>>>>> gcc/testsuite/g++.dg/
>>>>>         * diagnostic/pedantic.C: New test case.
>>>
>>> --- gcc-4.8.2-orig/gcc/cp/typeck.c      2014-03-31 22:29:42.736367936 -0300
>>> +++ gcc-4.8.2/gcc/cp/typeck.c   2014-03-31 14:26:43.536747050 -0300
>>> @@ -6639,7 +6639,7 @@
>>>            where possible, and it is necessary in some cases.  DR 195
>>>            addresses this issue, but as of 2004/10/26 is still in
>>>            drafting.  */
>>> -       warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
>>> +       warning (OPT_Wpedantic, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
>>>        return fold_if_not_in_template (build_nop (type, expr));
>>>      }
>>>    else if (TREE_CODE (type) == VECTOR_TYPE)
>>> --- gcc-4.8.2-orig/gcc/testsuite/g++.dg/diagnostic/pedantic.C   1969-12-31 21:00:00.000000000 -0300
>>> +++ gcc-4.8.2/gcc/testsuite/g++.dg/diagnostic/pedantic.C        2014-03-31 17:24:42.532607344 -0300
>>> @@ -0,0 +1,12 @@
>>> +// { dg-do compile }
>>> +// { dg-options "-pedantic" }
>>> +typedef void F(void);
>>> +
>>> +void foo()
>>> +{
>>> +    void* p = 0;
>>> +    F* f1 = reinterpret_cast<F*>(p);    // { dg-warning "ISO" }
>>> +#pragma GCC diagnostic ignored "-pedantic"
>>> +    F* f2 = reinterpret_cast<F*>(p);
>>> +}
>>> +
>>
>>
>>
>> --
>>
>> Daniel F. Gutson
>> Chief Engineering Officer, SPD
>>
>>
>> San Lorenzo 47, 3rd Floor, Office 5
>>
>> CÃrdoba, Argentina
>>
>>
>> Phone: +54 351 4217888 / +54 351 4218211
>>
>> Skype: dgutson
>
>
>
> --
>
> Daniel F. Gutson
> Chief Engineering Officer, SPD
>
>
> San Lorenzo 47, 3rd Floor, Office 5
>
> CÃrdoba, Argentina
>
>
> Phone: +54 351 4217888 / +54 351 4218211
>
> Skype: dgutson



-- 

Daniel F. Gutson
Chief Engineering Officer, SPD


San Lorenzo 47, 3rd Floor, Office 5

CÃrdoba, Argentina


Phone: +54 351 4217888 / +54 351 4218211

Skype: dgutson