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Re: pointer arithmetic question.

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pete wrote:
> 
> somenath wrote:
> >
> > Hi All,
> >
> > The following program is crashing.
> 
> >         char s[] ="test";
> >         char *t=s;
> 
> >                  *t = toupper(*t++);
> >                  //t++;

> > But how that can happen also ? As post increment operator's side
> > effect will be taking effect after the sequence point in this case
> > after execution of the code *t = toupper(*t++);

> Also,
> for the above definition of (t),
> the opcode for this expression: (t++)
> may or may not be
> the same as the opcode for this expression: (++t, t-1).
> Whether the side effect takes place before
> or after the value of (t++)is determined,
> is up to the implementation.

That's the old way.
In the new standard, 
there is a sequence point 
in the value of a postfix increment expression.

n1570
6.5.2.4 Postfix increment and decrement operators
2   The value computation of the result is sequenced    
    before the side effect of updating the stored value of the operand.

-- 
pete

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Thread

pointer arithmetic question. somenath <somenathpal@gmail.com> - 2012-05-05 21:46 -0700
  Re: pointer arithmetic question. Philip Lantz <prl@canterey.us> - 2012-05-05 23:25 -0700
    Re: pointer arithmetic question. Paul N <gw7rib@aol.com> - 2012-05-06 07:52 -0700
  Re: pointer arithmetic question. Kaz Kylheku <kaz@kylheku.com> - 2012-05-06 06:58 +0000
  Re: pointer arithmetic question. pete <pfiland@mindspring.com> - 2012-05-06 08:53 -0400
    Re: pointer arithmetic question. pete <pfiland@mindspring.com> - 2012-05-08 06:35 -0400
      Re: pointer arithmetic question. Tim Rentsch <txr@alumni.caltech.edu> - 2012-05-08 06:37 -0700
        Re: pointer arithmetic question. Kaz Kylheku <kaz@kylheku.com> - 2012-05-08 14:32 +0000
          Re: pointer arithmetic question. Tim Rentsch <txr@alumni.caltech.edu> - 2012-05-08 10:31 -0700
            Re: pointer arithmetic question. Kaz Kylheku <kaz@kylheku.com> - 2012-05-09 21:04 +0000
              Re: pointer arithmetic question. Tim Rentsch <txr@alumni.caltech.edu> - 2012-05-10 10:06 -0700
                Re: pointer arithmetic question. Kaz Kylheku <kaz@kylheku.com> - 2012-05-11 17:52 +0000
                Re: pointer arithmetic question. Tim Rentsch <txr@alumni.caltech.edu> - 2012-05-11 19:27 -0700

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