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Re: Unexpected output

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On 9/10/2011 3:59 PM, China Blue Corn Chips wrote:
> In article<8787e0b5-b4c3-463f-bd9a-6ffc30034950@x29g2000prh.googlegroups.com>,
>   Mazen<neurohacks@gmail.com>  wrote:
>
>> Hello,
>>
>> Following is a simple program:
>>
>> #include<stdio.h>
>>
>> int main(void) {
>>    int i = 0, j, k;
>>    j = k = 2;
>>
>>    printf("%d %d\n", i=+j, i=-j);
>>
>>    return 0;
>> }
>>
>> The output is
>> 2 2
>>
>> Shouldn't the second expression be -2 rather than 2? I'm confused.
>> Your insights pls. Thanks!
>
> The order of evaluation of function arguments is left to the implementation.

And, more importantly, modifying "i" twice without a sequence point between 
is UB.

-- 
Kenneth Brody

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Unexpected output Mazen <neurohacks@gmail.com> - 2011-09-10 12:36 -0700
  Re: Unexpected output China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-09-10 12:59 -0700
    Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-10 16:42 -0400
      Re: Unexpected output Mazen <neurohacks@gmail.com> - 2011-09-10 17:51 -0700
        Re: Unexpected output Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-09-10 20:38 -0600
        Re: Unexpected output pete <pfiland@mindspring.com> - 2011-09-10 22:41 -0400
        Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-11 09:35 -0400
          Re: Unexpected output gazelle@shell.xmission.com (Kenny McCormack) - 2011-09-11 13:39 +0000
        Re: Unexpected output "BartC" <bc@freeuk.com> - 2011-09-11 15:26 +0100
      Re: Unexpected output Paul N <gw7rib@aol.com> - 2011-09-11 12:08 -0700
        Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-11 17:43 -0400
    Re: Unexpected output Mazen <neurohacks@gmail.com> - 2011-09-10 13:24 -0700
      Re: Unexpected output China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-09-10 15:02 -0700
    Re: Unexpected output Kenneth Brody <kenbrody@spamcop.net> - 2011-09-12 10:01 -0400
  Re: Unexpected output arni <arnmin@gmail.com> - 2011-09-10 13:31 -0700
    Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-10 16:49 -0400
      Re: Unexpected output arni <arnmin@gmail.com> - 2011-09-10 14:13 -0700
        Re: Unexpected output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-10 17:26 -0400
          Re: Unexpected output Mazen <neurohacks@gmail.com> - 2011-09-10 17:59 -0700
            Re: Unexpected output Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-09-10 20:52 -0600
              Re: Unexpected output China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-09-10 19:55 -0700
              Re: Unexpected output Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-09-11 06:03 -0700
                Re: Unexpected output James Kuyper <jameskuyper@verizon.net> - 2011-09-11 14:04 -0400
            Re: Unexpected output Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-11 11:22 +0100
            Re: Unexpected output Keith Thompson <kst-u@mib.org> - 2011-09-11 11:01 -0700
              Re: Unexpected output Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-09-13 14:09 +0300
        Re: Unexpected output Seebs <usenet-nospam@seebs.net> - 2011-09-13 06:44 +0000
    Re: Unexpected output "Morris Keesan" <mkeesan@post.harvard.edu> - 2011-09-10 17:16 -0400
  Re: Unexpected output "BartC" <bc@freeuk.com> - 2011-09-10 23:20 +0100
  Re: Unexpected output August Karlstrom <fusionfile@gmail.com> - 2011-09-11 22:55 +0200
    Re: Unexpected output Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-11 22:51 +0100
      Re: Unexpected output pete <pfiland@mindspring.com> - 2011-09-11 22:25 -0400
      Re: Unexpected output August Karlstrom <fusionfile@gmail.com> - 2011-09-12 15:34 +0200
        Re: Unexpected output Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-12 19:55 +0100
          Re: Unexpected output August Karlstrom <fusionfile@gmail.com> - 2011-09-13 19:22 +0200

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