Re: In how many ways should this fail?

From	Kaz Kylheku <kaz@kylheku.com>
Newsgroups	comp.lang.c
Subject	Re: In how many ways should this fail?
Date	2012-01-30 17:21 +0000
Organization	A noiseless patient Spider
Message-ID	<20120130091432.218@kylheku.com> (permalink)
References	<87hazdcikg.fsf@huddi.jernurt.dk>

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On 2012-01-30, Anders Wegge Keller <wegge@wegge.dk> wrote:
>
>  At work, we got into a talk about weird C constructs. One of my
> collegues volunteered this line:
>
>  (a>b)?a:b = 42;
>
>  According to him, he have found three different compilers with three
> different ways of handling this. 

Some compilers accept a nonstandard dialect with extensions by default and have
to be told to interpret the input language as ISO C.

In the GNU C dialect, it is possible assign "through" the ternary operator.

In the C++ dialect of C, you can do this also, so if you compile code as either
C or C++, you may run into this working under C++, but then breaking when
someone runs the C build.

ISO C does not have this feature: the result of A ? B : C is not an lvalue.

Very recent case in point: http://www.kylheku.com/cgit/txr/commit/?id=5ae4654a4c6961d35b9bb4833934c51f17936df6

>  We ended up discussing what the acutal problem here is.

Probably, that of not knowing that there exist different dialects of C, and that
your compiler might not be using the one you think it is.

Thread

In how many ways should this fail? Anders Wegge Keller <wegge@wegge.dk> - 2012-01-30 16:32 +0100
  Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-01-30 11:07 -0500
    Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-01-30 11:11 -0500
    Re: In how many ways should this fail? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-30 17:42 +0000
  Re: In how many ways should this fail? gwowen <gwowen@gmail.com> - 2012-01-30 08:16 -0800
    Re: In how many ways should this fail? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-30 17:35 +0000
      Re: In how many ways should this fail? gwowen <gwowen@gmail.com> - 2012-01-30 23:47 -0800
      Re: In how many ways should this fail? Tim Rentsch <txr@alumni.caltech.edu> - 2012-02-01 00:00 -0800
        Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-02-01 12:14 +0000
          Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-02-01 08:04 -0500
          Re: In how many ways should this fail? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-01 13:31 +0000
        Re: In how many ways should this fail? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-01 12:59 +0000
          Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-02-01 08:37 -0500
            Re: In how many ways should this fail? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-01 16:40 +0000
              Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-02-01 12:13 -0500
                Re: In how many ways should this fail? Tim Rentsch <txr@alumni.caltech.edu> - 2012-03-08 12:49 -0800
    Re: In how many ways should this fail? Anders Wegge Keller <wegge@wegge.dk> - 2012-01-30 19:20 +0100
  Re: In how many ways should this fail? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-01-30 08:30 -0800
    Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-30 16:43 +0000
      Re: In how many ways should this fail? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-01-30 09:17 -0800
      Re: In how many ways should this fail? Kaz Kylheku <kaz@kylheku.com> - 2012-01-30 17:31 +0000
      Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-01-30 12:31 -0500
        Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-30 18:16 +0000
          Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-01-30 14:05 -0500
            Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-30 19:30 +0000
              Re: In how many ways should this fail? Keith Thompson <kst-u@mib.org> - 2012-01-30 12:50 -0800
              Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-01-30 16:17 -0500
              Re: In how many ways should this fail? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-30 21:48 +0000
                Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-31 12:43 +0000
                Re: In how many ways should this fail? Zoltan Kocsi <zoltan@bendor.com.au> - 2012-02-01 00:46 +1100
                Re: In how many ways should this fail? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-31 13:57 +0000
                Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-31 15:05 +0000
                Re: In how many ways should this fail? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-01-31 07:16 -0800
                Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-31 17:37 +0000
                Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-01-31 11:34 -0500
                Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-31 17:39 +0000
                Re: In how many ways should this fail? Keith Thompson <kst-u@mib.org> - 2012-01-31 19:42 -0800
                Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-02-01 11:57 +0000
                Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-02-01 08:14 -0500
                Re: In how many ways should this fail? Philip Lantz <prl@canterey.us> - 2012-02-01 00:04 -0800
                Re: In how many ways should this fail? James Kuyper <jameskuyper@verizon.net> - 2012-01-31 09:05 -0500
                Re: In how many ways should this fail? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-01-31 06:45 -0800
                Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-31 17:34 +0000
                Re: In how many ways should this fail? Keith Thompson <kst-u@mib.org> - 2012-01-31 19:26 -0800
                Re: In how many ways should this fail? Keith Thompson <kst-u@mib.org> - 2012-01-31 19:29 -0800
        Re: In how many ways should this fail? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-30 21:28 +0000
  Re: In how many ways should this fail? timprince <tprince@computer.org> - 2012-01-30 11:44 -0500
    Re: In how many ways should this fail? Kaz Kylheku <kaz@kylheku.com> - 2012-01-30 17:35 +0000
  Re: In how many ways should this fail? Kaz Kylheku <kaz@kylheku.com> - 2012-01-30 17:21 +0000
    Re: In how many ways should this fail? Anders Wegge Keller <wegge@wegge.dk> - 2012-01-30 19:22 +0100
      Re: In how many ways should this fail? 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-30 11:09 -0800
  Re: In how many ways should this fail? jacob navia <jacob@spamsink.net> - 2012-01-30 19:04 +0100
    Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-30 18:21 +0000
      Re: In how many ways should this fail? Jens Gustedt <jens.gustedt@loria.fr> - 2012-01-30 20:15 +0100
        Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-30 19:32 +0000
          Re: In how many ways should this fail? Jens Gustedt <jens.gustedt@loria.fr> - 2012-01-30 21:01 +0100
            Re: In how many ways should this fail? "BartC" <bc@freeuk.com> - 2012-01-30 20:22 +0000
              Re: In how many ways should this fail? Keith Thompson <kst-u@mib.org> - 2012-01-30 12:56 -0800
  Re: In how many ways should this fail? blp@cs.stanford.edu (Ben Pfaff) - 2012-01-30 10:07 -0800

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