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Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle...

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On 07/11/2015 01:04 PM, David Kleinecke wrote:
> On Saturday, July 11, 2015 at 7:25:35 AM UTC-7, Tim Rentsch wrote:
...
>> In C90 'sizeof' is a keyword, and an operator, and an identifier.
>> Since it is an identifier, how it is treated by the preprocessor
>> is described in 6.8.1 p1.
> 
> The pre-processor doesn't know about keywords. 6.1 lists what the
> preprocessing tokens are. Two of the categories are identifier and
> operator. "sizeof" is, of course, a identifier but it is also listed
> (6.1.5) as an operator. This is an ambiguity which I think people
> would resolve in favor of 6.1.5 because "sizeof" actually is an
> operator. So far as I can tell this ambiguity makes no effective
> difference in anything. But it distracts from the elegance of the
> standard.

You're probably referencing the C90 standard, because that description
doesn't match the current standard. You'll be pleased to know, I assume,
that in C99 and later versions there is no such ambiguity.

There are two separate grammars for C. The lexical grammar summarized in
Appendix A.1 applies to pre-processing tokens during translation phases
3-5. Preprocessing tokens are converted to tokens during translation
phase 6. The phrase structure grammar described in A.2 applies to tokens
during translation phase 7.
Most operators parse as punctuators (6.4.6p1), throughout phases 3-7,
while sizeof parses as an identifier (6.4.2.1p1) during phases 3-5, and
as a keyword (6.4.1p1) token during phase 7. All of the relevant
categories are well defined, there is no ambiguity.
Neither grammar identifies a syntactic category that includes all
operators - because there are no grammar rules where such a category
would be useful. The phrase structure grammar does define unary-operator
and assignment-operator, because those categories are used in grammar
productions (6.5.3p1 and 6.5.16p1, respectively). But most operators
appear in the grammar only on their own, in their own grammar
productions, with sizeof appearing in two of the grammar productions for
unary-expression.

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Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... G G <gdotone@gmail.com> - 2015-05-07 17:12 -0700
  Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-05-07 18:18 -0700
    Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... G G <gdotone@gmail.com> - 2015-05-07 20:16 -0700
      Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... mark.bluemel@gmail.com - 2015-05-08 01:09 -0700
      Re: Could you please discuss whether casting a size_t variable to   unsigned int variable is the correct way to handle... Tim Prince <tprince@computer.org> - 2015-05-08 09:16 -0400
      Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-05-08 08:03 -0700
        Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-05-08 10:30 -0700
          Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... jadill33@gmail.com - 2015-05-08 11:12 -0700
          Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-05-08 11:22 -0700
            Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-05-08 18:42 +0000
          Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Bartc <bc@freeuk.com> - 2015-05-08 19:25 +0100
            Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Stephen Sprunk <stephen@sprunk.org> - 2015-05-08 15:12 -0500
              Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Bartc <bc@freeuk.com> - 2015-05-08 22:38 +0100
                Re: Could you please discuss whether casting a size_t variable to   unsigned int variable is the correct way to handle... Ian Collins <ian-news@hotmail.com> - 2015-05-09 11:01 +1200
        Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-10 09:19 -0700
          Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-05-10 11:26 -0700
            Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-11 21:31 -0700
              Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-05-12 05:50 +0000
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-05-12 10:05 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-12 11:10 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-05-12 12:59 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-22 08:11 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-05-22 11:20 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-24 07:59 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-05-24 13:44 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-12 11:09 -0700
              Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-05-12 11:02 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-22 08:01 -0700
            Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Waldek Hebisch <hebisch@antispam.uni.wroc.pl> - 2015-06-08 01:06 +0000
              Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-06-07 19:12 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... James Kuyper <jameskuyper@verizon.net> - 2015-06-08 11:28 -0400
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Waldek Hebisch <hebisch@antispam.uni.wroc.pl> - 2015-06-09 12:23 +0000
            Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... David Kleinecke <dkleinecke@gmail.com> - 2015-06-08 10:56 -0700
              Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-06-08 11:32 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Bartc <bc@freeuk.com> - 2015-06-08 19:40 +0100
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Richard Heathfield <rjh@cpax.org.uk> - 2015-06-08 20:03 +0100
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-06-08 13:43 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-06-08 21:03 +0000
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-06-08 14:52 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... David Kleinecke <dkleinecke@gmail.com> - 2015-06-09 08:30 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-06-09 16:48 +0100
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-06-09 08:55 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... David Kleinecke <dkleinecke@gmail.com> - 2015-06-10 10:09 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-06-10 11:05 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... David Kleinecke <dkleinecke@gmail.com> - 2015-06-11 11:04 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-06-11 11:31 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-06-11 13:49 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... David Kleinecke <dkleinecke@gmail.com> - 2015-06-12 09:00 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Tim Rentsch <txr@alumni.caltech.edu> - 2015-07-11 07:25 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... David Kleinecke <dkleinecke@gmail.com> - 2015-07-11 10:04 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... James Kuyper <jameskuyper@verizon.net> - 2015-07-11 13:39 -0400
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Tim Rentsch <txr@alumni.caltech.edu> - 2015-07-11 13:44 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Keith Thompson <kst-u@mib.org> - 2015-07-11 16:15 -0700
                Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... David Kleinecke <dkleinecke@gmail.com> - 2015-06-09 08:31 -0700
  Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-05-07 20:34 -0700
    Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... Richard Heathfield <rjh@cpax.org.uk> - 2015-05-08 09:48 +0100
  Re: Could you please discuss whether casting a size_t variable to unsigned int variable is the correct way to handle... glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-05-08 05:12 +0000

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