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Re: Do not cast pointers to functions to pointers to primitive types

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In article <lnpq62vkuk.fsf@nuthaus.mib.org>,
Keith Thompson  <kst-u@mib.org> wrote:
>James Kuyper <jameskuyper@verizon.net> writes:
>> On 09/03/2012 04:21 PM, Keith Thompson wrote:
>>> James Kuyper <jameskuyper@verizon.net> writes:
>>> [...]
>>>> Example: the dlsym() function is specified by the X-open standard to
>>>> take a void* argument which can be either a pointer to an object or a
>>>> pointer to a function. The Rationale for that function notes;
>>>>
>>> [...]
>>>>> Note that compilers conforming to the ISO C standard are required to
>>>>> generate a warning if a conversion from a void * pointer to a
>>>>> function pointer is attempted.
>>> [...]
>>> 
>>> I don't believe that's correct.  The behavior of converting a void*
>>> pointer to a function pointer is not defined, but as far as I can tell
>>> it doesn't violate any constraint.
>[...]
>>
>> It's possible that they're referring to implicit conversion, rather than
>> one using a cast.
>
>It's possible, but if so they phrased it poorly.

Any idiot should be able to read that and know without being told that using
a cast will get rid of the warning. Casts do that. It's obvious.

-- 
Alan Curry

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Thread

Do not cast pointers to functions to pointers to primitive types ajaybgr <ajay.bgr@gmail.com> - 2012-09-03 01:50 -0700
  Re: Do not cast pointers to functions to pointers to primitive types Ian Collins <ian-news@hotmail.com> - 2012-09-03 20:59 +1200
  Re: Do not cast pointers to functions to pointers to primitive types Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-09-03 02:13 -0700
  Re: Do not cast pointers to functions to pointers to primitive types Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-09-03 11:24 +0100
  Re: Do not cast pointers to functions to pointers to primitive types James Kuyper <jameskuyper@verizon.net> - 2012-09-03 08:31 -0400
    Re: Do not cast pointers to functions to pointers to primitive types Keith Thompson <kst-u@mib.org> - 2012-09-03 13:21 -0700
      Re: Do not cast pointers to functions to pointers to primitive types James Kuyper <jameskuyper@verizon.net> - 2012-09-03 16:57 -0400
        Re: Do not cast pointers to functions to pointers to primitive types Keith Thompson <kst-u@mib.org> - 2012-09-03 14:48 -0700
          Re: Do not cast pointers to functions to pointers to primitive types pacman@kosh.dhis.org (Alan Curry) - 2012-09-03 21:57 +0000
            Re: Do not cast pointers to functions to pointers to primitive types Keith Thompson <kst-u@mib.org> - 2012-09-03 18:11 -0700
              Re: Do not cast pointers to functions to pointers to primitive types pacman@kosh.dhis.org (Alan Curry) - 2012-09-04 02:03 +0000
                Re: Do not cast pointers to functions to pointers to primitive types Keith Thompson <kst-u@mib.org> - 2012-09-03 19:20 -0700
                Re: Do not cast pointers to functions to pointers to primitive types pacman@kosh.dhis.org (Alan Curry) - 2012-09-04 20:27 +0000
                Re: Do not cast pointers to functions to pointers to primitive types James Kuyper <jameskuyper@verizon.net> - 2012-09-04 17:10 -0400
                Re: Do not cast pointers to functions to pointers to primitive types Barry Schwarz <schwarzb@dqel.com> - 2012-09-04 14:14 -0700
          Re: Do not cast pointers to functions to pointers to primitive types pete <pfiland@mindspring.com> - 2012-09-03 22:51 -0400
      Re: Do not cast pointers to functions to pointers to primitive types Vincenzo Mercuri <vincenzo.mercuri@yahoo.it> - 2012-09-04 00:02 +0200
        Re: Do not cast pointers to functions to pointers to primitive types Keith Thompson <kst-u@mib.org> - 2012-09-03 18:19 -0700
  Re: Do not cast pointers to functions to pointers to primitive types Kaz Kylheku <kaz@kylheku.com> - 2012-09-04 01:18 +0000
    Re: Do not cast pointers to functions to pointers to primitive types "Scott Fluhrer" <sfluhrer@ix.netcom.com> - 2012-09-04 11:59 -0400
      Re: Do not cast pointers to functions to pointers to primitive types Philip Lantz <prl@canterey.us> - 2012-09-06 21:34 -0700

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