Re: Why sizeof(main) = 1?

From	James Kuyper <jameskuyper@verizon.net>
Newsgroups	comp.lang.c.moderated
Subject	Re: Why sizeof(main) = 1?
Date	2013-09-12 11:29 -0500
Organization	A noiseless patient Spider
Message-ID	<clcm-20130912-0002@plethora.net> (permalink)
References	<clcm-20130104-0002@plethora.net> <clcm-20130902-0002@plethora.net> <clcm-20130906-0003@plethora.net> <clcm-20130911-0004@plethora.net>

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On 09/11/2013 06:27 PM, Robert Wessel wrote:
> On Fri, 6 Sep 2013 23:25:44 -0500 (CDT), Keith Thompson
> <kst-u@mib.org> wrote:
...
>>    if (main) yadda;
>>
>> is well defined but not useful, since `main`, after conversion,
>> can never be a null pointer.
> 
> 
> Is that actually true?  Certainly any valid data-type object cannot
> have an address of zero/NULL, but is that true of function objects?

"a null pointer ... is guaranteed to compare unequal
to a pointer to any object or function." (6.3.2.3p3)
"Two pointers compare equal if ... both are null pointers." (6.5.9p6)
If a pointer to main were a null pointer, those two requirements would
be in conflict.
-- 
James Kuyper
-- 
comp.lang.c.moderated - moderation address: clcm@plethora.net -- you must
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Thread

Why sizeof(main) = 1? Myth__Buster <raghavanil4m@gmail.com> - 2013-01-04 18:14 -0600
  Re: Why sizeof(main) = 1? Barry Schwarz <schwarzb@dqel.com> - 2013-02-26 10:51 -0600
    Re: Why sizeof(main) = 1? Keith Thompson <kst-u@mib.org> - 2013-03-11 18:25 -0500
  Re: Why sizeof(main) = 1? Jasen Betts <jasen@xnet.co.nz> - 2013-02-26 10:51 -0600
  Re: Why sizeof(main) = 1? gordonb.k8xjg@burditt.org (Gordon Burditt) - 2013-02-26 10:51 -0600
  Re: Why sizeof(main) = 1? <kzelechowski@e3tech.local> - 2013-09-02 04:07 -0500
    Re: Why sizeof(main) = 1? James Kuyper <jameskuyper@verizon.net> - 2013-09-06 23:25 -0500
      Re: Why sizeof(main) = 1? Keith Thompson <kst-u@mib.org> - 2013-09-11 17:26 -0500
        Re: Why sizeof(main) = 1? James Kuyper <jameskuyper@verizon.net> - 2013-09-12 11:29 -0500
    Re: Why sizeof(main) = 1? Keith Thompson <kst-u@mib.org> - 2013-09-06 23:25 -0500
      Re: Why sizeof(main) = 1? Robert Wessel <robertwessel2@yahoo.com> - 2013-09-11 17:27 -0500
        Re: Why sizeof(main) = 1? James Kuyper <jameskuyper@verizon.net> - 2013-09-12 11:29 -0500
        Re: Why sizeof(main) = 1? Keith Thompson <kst-u@mib.org> - 2013-09-12 11:30 -0500
    Re: Why sizeof(main) = 1? Ken Brody <kenbrody@spamcop.net> - 2013-09-06 23:25 -0500

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