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Re: What is the value after operator '!'?

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supercat@casperkitty.com wrote:
> On Monday, October 26, 2015 at 1:05:12 PM UTC-5, Keith Thompson wrote:
>> There is.  The expression 0 is of type int.  In p==0, if p is of pointer
>> type, the expression 0 is converted, via the special-case rule in N1570
>> 6.3.2.3p3, from int to the type of p.  (This conversion is almost
>> certainly done at compile time, though the standard doesn't say so.)
>
> In a system where (char*)x would yield a pointer to physical address x,
> and where physical address zero was valid, but where (char*)0 [i.e. NULL]
> was represented by a pointer with some physical address other than zero,
> would there be any way of writing a pointer constant equal to physical
> address zero?

An argument for C adopting nullptr from C++?

-- 
Ian Collins

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Thread

What is the value after operator '!'? fl <rxjwg98@gmail.com> - 2015-10-26 06:21 -0700
  Re: What is the value after operator '!'? Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-10-26 09:29 -0400
  Re: What is the value after operator '!'? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-26 13:42 +0000
    Re: What is the value after operator '!'? supercat@casperkitty.com - 2015-10-26 07:53 -0700
      Re: What is the value after operator '!'? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-26 17:37 +0000
        Re: What is the value after operator '!'? Keith Thompson <kst-u@mib.org> - 2015-10-26 11:05 -0700
          Re: What is the value after operator '!'? supercat@casperkitty.com - 2015-10-26 11:38 -0700
            Re: What is the value after operator '!'? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-10-26 20:27 +0000
              Re: What is the value after operator '!'? supercat@casperkitty.com - 2015-10-26 14:16 -0700
                Re: What is the value after operator '!'? Keith Thompson <kst-u@mib.org> - 2015-10-26 17:15 -0700
              Re: What is the value after operator '!'? Keith Thompson <kst-u@mib.org> - 2015-10-26 17:12 -0700
            Re: What is the value after operator '!'? Ian Collins <ian-news@hotmail.com> - 2015-10-27 10:27 +1300
            Re: What is the value after operator '!'? Keith Thompson <kst-u@mib.org> - 2015-10-26 15:15 -0700
              Re: What is the value after operator '!'? supercat@casperkitty.com - 2015-10-26 16:16 -0700
                Re: What is the value after operator '!'? Keith Thompson <kst-u@mib.org> - 2015-10-27 08:39 -0700
  Re: What is the value after operator '!'? Richard Heathfield <rjh@cpax.org.uk> - 2015-10-26 14:04 +0000
  Re: What is the value after operator '!'? Geoff <geoff@invalid.invalid> - 2015-10-26 09:50 -0700

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