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Re: Variables allocated on stack

From Ian Collins <ian-news@hotmail.com>
Newsgroups comp.lang.c
Subject Re: Variables allocated on stack
Date 2011-11-25 10:40 +1300
Message-ID <9j7ru9Fc8tU3@mid.individual.net> (permalink)
References <53159da6-37f6-4742-9ad0-2e3477ca8b0b@v8g2000yqk.googlegroups.com>

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On 11/25/11 10:28 AM, Bogdan wrote:
> Hi
>
>   I had during an interview this question: which variables are
> allocated on the stack in a function ? I am unsure how the output
> variable is handled. Is this one too allocated on the stack and popped
> when the function exists ?
> Here is an example:
>
> char* some_function(char c)
> {
>       char *out = malloc(10);
>       return out;
> }
>
> On the local stack are there one char and 2 pointers to chars ?

The question was bogus, either trick or the interviewer had a rather 
myopic viewpoint.

There isn't a correct answer.  On some machines (that do have a stack), 
nothing will be on the stack.  Both an and out will be in registers.

Then there machines that don't have a stack....

-- 
Ian Collins

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Thread

Variables allocated on stack Bogdan <cristeab@gmail.com> - 2011-11-24 13:28 -0800
  Re: Variables allocated on stack Ian Collins <ian-news@hotmail.com> - 2011-11-25 10:40 +1300
  Re: Variables allocated on stack jacob navia <jacob@spamsink.net> - 2011-11-24 23:30 +0100
    Re: Variables allocated on stack Quentin Pope <qp19433@hotmail.NOSPAM.com> - 2011-12-02 22:33 +0000
      Re: Variables allocated on stack jacob navia <jacob@spamsink.net> - 2011-12-03 00:54 +0100
      Re: Variables allocated on stack Malcolm McLean <malcolm.mclean5@btinternet.com> - 2011-12-02 23:33 -0800
        Re: Variables allocated on stack Keith Thompson <kst-u@mib.org> - 2011-12-03 02:25 -0800
  Re: Variables allocated on stack jt@toerring.de (Jens Thoms Toerring) - 2011-11-24 23:37 +0000
  Re: Variables allocated on stack Malcolm McLean <malcolm.mclean5@btinternet.com> - 2011-11-25 01:53 -0800
    Re: Variables allocated on stack "BartC" <bc@freeuk.com> - 2011-11-25 11:05 +0000
      Re: Variables allocated on stack jacob navia <jacob@spamsink.net> - 2011-11-25 12:11 +0100
        Re: Variables allocated on stack "BartC" <bc@freeuk.com> - 2011-11-25 11:40 +0000
          Re: Variables allocated on stack jacob navia <jacob@spamsink.net> - 2011-11-25 12:52 +0100
            Re: Variables allocated on stack Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-11-27 02:31 -0800
              Re: Variables allocated on stack jacob navia <jacob@spamsink.net> - 2011-11-27 13:28 +0100
              Re: Variables allocated on stack André Gillibert <MetaEntropy.removeThis@gmail.com> - 2011-11-27 13:44 +0100
                Re: Variables allocated on stack jacob navia <jacob@spamsink.net> - 2011-11-27 15:44 +0100
                Re: Variables allocated on stack André Gillibert <MetaEntropy.removeThis@gmail.com> - 2011-11-27 17:34 +0100
                Re: Variables allocated on stack jacob navia <jacob@spamsink.net> - 2011-11-27 18:28 +0100
                Re: Variables allocated on stack Ian Collins <ian-news@hotmail.com> - 2011-11-28 07:48 +1300
                Re: Variables allocated on stack gwowen <gwowen@gmail.com> - 2011-11-29 01:11 -0800
                Re: Variables allocated on stack jacob navia <jacob@spamsink.net> - 2011-11-29 17:02 +0100
          Re: Variables allocated on stack Seebs <usenet-nospam@seebs.net> - 2011-11-26 07:21 +0000
            Re: Variables allocated on stack "BartC" <bc@freeuk.com> - 2011-11-26 11:07 +0000
              Re: Variables allocated on stack Markus Wichmann <nullplan@gmx.net> - 2011-11-26 21:16 +0100
                Re: Variables allocated on stack "BartC" <bc@freeuk.com> - 2011-11-26 23:00 +0000
                Re: Variables allocated on stack Ian Collins <ian-news@hotmail.com> - 2011-11-27 12:12 +1300
                Re: Variables allocated on stack "BartC" <bc@freeuk.com> - 2011-11-26 23:35 +0000
                Re: Variables allocated on stack Ian Collins <ian-news@hotmail.com> - 2011-11-27 12:48 +1300
                Re: Variables allocated on stack Markus Wichmann <nullplan@gmx.net> - 2011-11-27 10:56 +0100
                Re: Variables allocated on stack Keith Thompson <kst-u@mib.org> - 2011-11-28 16:17 -0800
                Re: Variables allocated on stack Markus Wichmann <nullplan@gmx.net> - 2011-11-30 17:04 +0100
                Re: Variables allocated on stack Keith Thompson <kst-u@mib.org> - 2011-11-30 09:36 -0800
                Re: Variables allocated on stack Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 05:11 -0800
                Re: Variables allocated on stack Keith Thompson <kst-u@mib.org> - 2012-01-25 12:23 -0800
                Re: Variables allocated on stack Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-31 19:11 -0800
                Re: Variables allocated on stack Ian Collins <ian-news@hotmail.com> - 2011-11-27 13:06 +1300
                Re: Variables allocated on stack André Gillibert <MetaEntropy.removeThis@gmail.com> - 2011-11-27 11:20 +0100
                Re: Variables allocated on stack David Thompson <dave.thompson2@verizon.net> - 2012-01-19 02:43 -0500
              Re: Variables allocated on stack Seebs <usenet-nospam@seebs.net> - 2011-11-28 08:32 +0000
    Re: Variables allocated on stack Bogdan <cristeab@gmail.com> - 2011-11-26 01:18 -0800
      Re: Variables allocated on stack Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-26 08:36 -0500
  Re: Variables allocated on stack Seebs <usenet-nospam@seebs.net> - 2011-11-26 07:21 +0000
  Re: Variables allocated on stack Noob <root@127.0.0.1> - 2011-11-29 11:51 +0100

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