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Re: Two different Results between C and C++

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James Kuyper <jameskuyper@alumni.caltech.edu> writes:

> On Tuesday, September 8, 2020 at 11:27:37 AM UTC-4, Tim Rentsch wrote:
> ...
>
>> use Keith Thompson's phrase, and there is a tacit assumption
>> that the programs are well-formed (meaning no syntax errors or
>> constraint violations).
>
> I should have commented on this before.  You have frequently
> applied the term "well-formed" to C code, but as far as I can
> tell, Keith has never used the phrase "well-formed" at all in this
> discussion.
>
> I have used "well-formed", but only to describe C++ code.  There's
> a good reason for that.  The C++ standard defines the term
> "well-formed":  "C++ program constructed according to the syntax
> rules, diagnosable semantic rules, and the one-definition rule
> (6.2)."  (C++ 3.29).  C++ doesn't use formal "Constraints"
> sections the same way that C does, and code which obeys all of
> C++'s "diagnosable semantic rules" is (debatably) considerably
> more restricted than code which violates none of C's constraints.
>
> The concept of "Well-formed" code is not used in the C standard;
> the closest equivalent is "strictly conforming" (which, in a neat
> bit of symmetry, is not used in the C++ standard).  "strictly
> conforming" is considerably more restricted than "well-formed"
> (whether referring to your definition or the C++ standard's
> definition), since it doesn't allow for unspecified behavior.
>
> I wonder if this has had something to do with our point of
> disagreement.  The arguments I've made depend heavily upon the
> fact that strictly conforming code cannot produce output that
> depends upon unspecified behavior.

Let me offer some advice.  If you want to carry on a useful
conversation with someone, it is important first to understand
what they think they mean by what they say.  It doesn't help to
explain what you think their words should mean, and usually just
the opposite, because that will slow down the process of
understanding what it is they actually do mean.  So the question
now is what do you think I meant, which is to say what I thought
I meant, by my various comments in responses to Keith's postings?
Hint:  my use of "well-formed" had nothing to do with how the C++
standard may define that term.

If on the other hand you don't want to carry on a useful
conversation then the above advice may not apply.

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Re: Two different Results between C and C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-09-04 03:13 -0700
  Re: Two different Results between C and C++ Kaz Kylheku <793-849-0957@kylheku.com> - 2020-09-04 18:44 +0000
    Re: Two different Results between C and C++ David Brown <david.brown@hesbynett.no> - 2020-09-05 15:57 +0200
    Re: Two different Results between C and C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-09-08 08:27 -0700
      Re: Two different Results between C and C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-09-08 17:50 -0700
        Re: Two different Results between C and C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-09-08 21:07 -0400
        Re: Two different Results between C and C++ Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-09-08 18:28 -0700
          Re: Two different Results between C and C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-09-08 22:14 -0400
        Re: Two different Results between C and C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-09-10 06:35 -0700
  Re: Two different Results between C and C++ Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-09-04 11:46 -0700
    Re: Two different Results between C and C++ Kaz Kylheku <793-849-0957@kylheku.com> - 2020-09-04 19:07 +0000
    Re: Two different Results between C and C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-09-10 04:15 -0700
      Re: Two different Results between C and C++ Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-09-10 12:46 -0700

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