Re: is the < operator transitive?

From	Tim Rentsch <txr@alumni.caltech.edu>
Newsgroups	comp.lang.c
Subject	Re: is the < operator transitive?
Date	2012-01-24 16:14 -0800
Organization	A noiseless patient Spider
Message-ID	<kfnd3a8eiys.fsf@x-alumni2.alumni.caltech.edu> (permalink)
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Eric Sosman <esosman@ieee-dot-org.invalid> writes:

> On 10/9/2011 3:40 PM, Francois Grieu wrote:
>> On 08/10/2011 02:00, Eric Sosman wrote:
>>
>>> enum { MINUSONE = -1 };
>>>
>>> Now MINUSONE *is* an `int' constant with negative value, hence
>>>
>>> (MINUSONE < 0 && 0 < 1u && !(MINUSONE < 1u))
>>
>> Exactly the counterexample that I was looking after.
>
>     It's a bit of a nit-pick because it relies on sometimes converting
> and sometimes not converting an operand.  To the best of my knowledge,
> your original expression `( a<b && b<c && !(a<c) )' is guaranteed to be
> zero if (not "iff")
>
>     1: a,b,c are expressions of the same type, and
>     2: there are no side-effects (including `volatile' references)
>        in evaluating a,b,c, and
>     3: evaluating a,b,c produces no undefined behavior, and
>     4: the three comparisons are themselves defined (a,b,c aren't
>        structs, aren't pointers into unrelated arrays, etc.)

Can be 1 if a, b, and c are expressions with floating-point
operations in them.

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is the < operator transitive? Francois Grieu <fgrieu@gmail.com> - 2011-10-07 19:10 +0200
  Re: is the < operator transitive? Robert Wessel <robertwessel2@yahoo.com> - 2011-10-07 13:44 -0500
  Re: is the < operator transitive? Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2011-10-07 18:50 +0000
    Re: is the < operator transitive? Keith Thompson <kst-u@mib.org> - 2011-10-07 12:42 -0700
      Re: is the < operator transitive? Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2011-10-07 20:23 +0000
        Re: is the < operator transitive? Patrick Scheible <kkt@zipcon.net> - 2011-10-07 14:29 -0700
        Re: is the < operator transitive? Keith Thompson <kst-u@mib.org> - 2011-10-07 16:49 -0700
          Re: is the < operator transitive? Patrick Scheible <kkt@zipcon.net> - 2011-10-07 19:19 -0700
        Re: is the < operator transitive? Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-10-08 09:57 -0400
    Re: is the < operator transitive? "BartC" <bc@freeuk.com> - 2011-10-08 13:17 +0100
      Re: is the < operator transitive? Harald van Dĳk <truedfx@gmail.com> - 2011-10-08 06:06 -0700
        Re: is the < operator transitive? "BartC" <bc@freeuk.com> - 2011-10-08 14:48 +0100
          Re: is the < operator transitive? Harald van Dĳk <truedfx@gmail.com> - 2011-10-08 07:18 -0700
          Re: is the < operator transitive? "BartC" <bc@freeuk.com> - 2011-10-08 15:19 +0100
  Re: is the < operator transitive? Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2011-10-07 18:50 +0000
    Re: is the < operator transitive? jacob navia <jacob@spamsink.net> - 2011-10-07 21:23 +0200
      Re: is the < operator transitive? Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2011-10-07 20:24 +0000
        Re: is the < operator transitive? James Kuyper <jameskuyper@verizon.net> - 2011-10-07 16:40 -0400
          Re: is the < operator transitive? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-07 23:12 +0100
            Re: is the < operator transitive? Harald van Dĳk <truedfx@gmail.com> - 2011-10-07 15:28 -0700
              Re: is the < operator transitive? Harald van Dĳk <truedfx@gmail.com> - 2011-10-07 15:31 -0700
              Re: is the < operator transitive? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-07 23:36 +0100
                Re: is the < operator transitive? Patrick Scheible <kkt@zipcon.net> - 2011-10-07 16:18 -0700
                Re: is the < operator transitive? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-08 10:32 +0100
            Re: is the < operator transitive? James Kuyper <jameskuyper@verizon.net> - 2011-10-07 18:30 -0400
              Re: is the < operator transitive? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-08 00:21 +0100
                Re: is the < operator transitive? James Kuyper <jameskuyper@verizon.net> - 2011-10-07 21:33 -0400
                Re: is the < operator transitive? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-08 10:45 +0100
                Re: is the < operator transitive? James Kuyper <jameskuyper@verizon.net> - 2011-10-08 14:02 -0400
                Re: is the < operator transitive? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-08 21:49 +0100
                Re: is the < operator transitive? James Kuyper <jameskuyper@verizon.net> - 2011-10-08 17:17 -0400
                Re: is the < operator transitive? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-08 22:59 +0100
                Re: is the < operator transitive? James Kuyper <jameskuyper@verizon.net> - 2011-10-08 21:33 -0400
                Re: is the < operator transitive? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-09 09:09 +0100
                Re: is the < operator transitive? James Kuyper <jameskuyper@verizon.net> - 2011-10-09 07:00 -0400
                Re: is the < operator transitive? "BartC" <bc@freeuk.com> - 2011-10-09 01:12 +0100
                Re: is the < operator transitive? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-09 08:55 +0100
            Re: is the < operator transitive? Robert Wessel <robertwessel2@yahoo.com> - 2011-10-07 18:16 -0500
              Re: is the < operator transitive? David Thompson <dave.thompson2@verizon.net> - 2011-10-18 02:03 -0400
                Re: is the < operator transitive? Robert Wessel <robertwessel2@yahoo.com> - 2011-10-20 18:03 -0500
        Re: is the < operator transitive? Keith Thompson <kst-u@mib.org> - 2011-10-07 16:50 -0700
    Re: is the < operator transitive? "io_x" <a@b.c.invalid> - 2011-10-09 11:00 +0200
      Re: is the < operator transitive? Willem <willem@toad.stack.nl> - 2011-10-09 09:42 +0000
        Re: is the < operator transitive? Ike Naar <ike@sverige.freeshell.org> - 2011-10-09 12:20 +0000
          Re: is the < operator transitive? Willem <willem@toad.stack.nl> - 2011-10-09 12:40 +0000
            Re: is the < operator transitive? Ike Naar <ike@sverige.freeshell.org> - 2011-10-09 12:54 +0000
              Re: is the < operator transitive? Willem <willem@toad.stack.nl> - 2011-10-09 13:04 +0000
            Re: is the < operator transitive? "BartC" <bc@freeuk.com> - 2011-10-09 15:34 +0100
              Re: is the < operator transitive? Willem <willem@toad.stack.nl> - 2011-10-09 15:08 +0000
            Re: is the < operator transitive? Robert Wessel <robertwessel2@yahoo.com> - 2011-10-09 12:14 -0500
  Re: is the < operator transitive? James Kuyper <jameskuyper@verizon.net> - 2011-10-07 15:36 -0400
    Re: is the < operator transitive? Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-10-07 20:00 -0400
      Re: is the < operator transitive? James Kuyper <jameskuyper@verizon.net> - 2011-10-07 21:38 -0400
      Re: is the < operator transitive? Francois Grieu <fgrieu@gmail.com> - 2011-10-09 21:40 +0200
        Re: is the < operator transitive? Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-10-09 16:34 -0400
          Re: is the < operator transitive? Francois Grieu <fgrieu@gmail.com> - 2011-10-11 14:08 +0200
          Re: is the < operator transitive? Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-24 16:14 -0800

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