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Re: Pointers and Sequence Point

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James Kuyper <jameskuyper@verizon.net> writes:
> On 05/02/2011 12:36 PM, Chad wrote:
>> On May 2, 6:58�am, Martin Ambuhl <mamb...@earthlink.net> wrote:
>>> On 5/2/2011 7:38 AM, arnuld wrote:
>>>
>>>> I have this program which is causing confusion to me. I am told that last
>>>> printf() of main() will always print "Second", not "First". I think line:
>>>
>>>> � x = myAlloc(x);
>>>
>>> While it is possible to write evil code in which myAlloc could modify x,
>>> in C myAlloc receives a copy of the value of x and has no clue where x
>>> is or how to modify it. �There are not two or more instances of
>>> modifying x between sequence points.
>>>
>> 
>> What is the scope of 'x' in myAlloc(x)? Is confined to myAlloc()?
>
> The scope of 'x' starts at the declaration of 'x' on the first line of
> main(), and is restricted to the body of main(). It goes out of scope
> throughout the execution of myAlloc(). It comes back into scope after
> that function returns. It's scope ends when main() returns.

Your wording  seems to imply that 'x' goes into and out of scope
during execution.  In fact, an entity's scope is a region of
program text.  C99 6.2.1p2.

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

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Pointers and Sequence Point arnuld <sunrise@invalid.address> - 2011-05-02 11:38 +0000
  Re: Pointers and Sequence Point James Kuyper <jameskuyper@verizon.net> - 2011-05-02 08:23 -0400
  Re: Pointers and Sequence Point Martin Ambuhl <mambuhl@earthlink.net> - 2011-05-02 09:58 -0400
    Re: Pointers and Sequence Point Chad <cdalten@gmail.com> - 2011-05-02 09:36 -0700
      Re: Pointers and Sequence Point Angel <angel+news@spamcop.net> - 2011-05-02 17:21 +0000
      Re: Pointers and Sequence Point James Kuyper <jameskuyper@verizon.net> - 2011-05-02 23:20 -0400
        Re: Pointers and Sequence Point Keith Thompson <kst-u@mib.org> - 2011-05-02 23:26 -0700
          Re: Pointers and Sequence Point James Kuyper <jameskuyper@verizon.net> - 2011-05-03 05:33 -0400
    Re: Pointers and Sequence Point Kenneth Brody <kenbrody@spamcop.net> - 2011-05-02 13:35 -0400
      Re: Pointers and Sequence Point Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-05-03 17:45 +0300
  Re: Pointers and Sequence Point John Bode <jfbode1029@gmail.com> - 2011-05-02 10:17 -0700
  Re: Pointers and Sequence Point Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-02 10:31 -0700
  Re: Pointers and Sequence Point "Morris Keesan" <mkeesan@post.harvard.edu> - 2011-05-02 20:55 -0400
    Re: Pointers and Sequence Point David Resnick <lndresnick@gmail.com> - 2011-05-03 08:01 -0700

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