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Re: Type interchange

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pete <pfiland@mindspring.com> writes:
> Keith Thompson wrote:
[...]
>> Let's make it a complete program:
>> 
>> int main(void) {
>>     int n = 32767;
>>     n ++;
>>     return 0;
>> }
>> 
>> I say that this program (specifically its execution) has undefined
>> behavior under an implementation with INT_MAX == 32767, and has
>> well defined behavior under an implementation with INT_MAX > 32767.
>> 
>> What do you say?  Are you claiming that the program's behavior is
>> undefined regardless of the implementation?
>
> Yes.
>
> That's an example of a non portable construct
> for which the standard imposes no requirements.

And that's where I think you're wrong.  It's a non-portable construct
for which the standard *does* impose a requirement.  The requirement is
that if INT_MAX > 32767, then the value of n after "n ++;" shall be
32768.

Given a revised program:

#include <stdio.h>
int main(void) {
    int n = 32767;
    n ++;
    printf("n = %d\n", n);
    return 0;
}

do you believe that, on an implementation with INT_MAX > 32767,
and in the absence of I/O errors, that program can do anything
other than printing "n = 32768"?

A conditional requirement is still a requirement.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
    Will write code for food.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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Thread

Type interchange Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2011-11-30 21:53 +0000
  Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-11-30 17:29 -0500
    Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-11-30 15:22 -0800
      Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-11-30 19:10 -0500
        Re: Type interchange Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-01 03:09 +0000
          Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 07:13 -0500
            Re: Type interchange Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-01 15:55 +0000
              Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 11:28 -0500
                Re: Type interchange Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-01 16:45 +0000
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 12:00 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 14:31 -0800
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 20:18 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 17:35 -0800
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-02 12:03 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-02 13:49 -0800
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-02 22:12 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-03 02:01 -0800
                Re: Type interchange Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 12:47 -0800
            Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-01 11:10 -0500
              Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 11:34 -0500
              Re: Type interchange Kaz Kylheku <kaz@kylheku.com> - 2011-12-01 17:48 +0000
              Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 14:17 -0800
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-01 17:43 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 15:00 -0800
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-01 19:29 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 16:59 -0800
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-02 08:35 -0500
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-02 08:46 -0500
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-02 13:32 -0800
                Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-02 13:30 -0800
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-02 18:45 -0500
        Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-11-30 19:17 -0800
          Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 06:50 -0500
            Re: Type interchange Keith Thompson <kst-u@mib.org> - 2011-12-01 07:15 -0800
              Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 10:36 -0500
                Re: Type interchange pete <pfiland@mindspring.com> - 2011-12-01 11:04 -0500
                Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-01 11:37 -0500
                Re: Type interchange Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 13:02 -0800
            Re: Type interchange Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 13:01 -0800
    Re: Type interchange Quentin Pope <qp19433@hotmail.NOSPAM.com> - 2011-12-02 22:15 +0000
      Re: Type interchange James Kuyper <jameskuyper@verizon.net> - 2011-12-03 11:39 -0500

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