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Re: bart again (UCX64)

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Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:

> James Kuyper <jameskuyper@alumni.caltech.edu> writes:
>
>> On 2023-11-18 at 00:17 EST, Tim Rentsch wrote:
>>
>>> I don't remember any outstanding question from the discussion of
>>> falling off the end of a non-void function.  Looking back over
>>> postings from you responding to a posting of mine I don't see
>>> any either.  I guess it's possible there was a question but I
>>> didn't see it.  In any case I have no idea what question in that
>>> thread you want answered, so if you still want an answer please
>>> ask the question again.
>>
>> The question he was referring to was the very last sentence of the
>> following text, which comes from a message posted on the thread titled
>> "bart again (UCX64)".  You never answered it.  Keith posted three more
>> messages on that subthread repeating the question and asking why you had
>> not bothered answering it.  You answered with the same useless comments
>> about needing a "shared understanding of what the statement means" that
>> you're using in this thread.  What makes those comments useless is not
>> that they are wrong, but that you failed to explain what understanding
>> you think is not shared between you and Keith.  Because you failed to
>> explain that, I have no idea why you think it's needed to answer a
>> simple straightforward question like the following:
>>
>> On 9/4/23 21:57, Keith Thompson wrote:
>>
>>> Tim Rentsch <tr.17687@z991.linuxsc.com> writes:
>>>
>>>> Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:
>>>>
>>>>> David Brown <david.brown@hesbynett.no> writes:
>>>>>
>>>>>> On 04/09/2023 12:06, Bart wrote:
>>>>>
>>>>> [...]
>>>>>
>>>>>>>   char* fred(void) {
>>>>>>>   (long long int)rand()*3.14159;
>>>>>>>   }
>>>>>>>   int main(void) {
>>>>>>>   printf("%s\n", fred());
>>>>>>>   }
>>>>>
>>>>> [...]
>>>>>
>>>>>> As you know, it is not valid C code.  As you know, proper C compilers
>>>>>> will - at least - warn you about it when asked to treat the input
>>>>>> according to the C standards.  As you know, there isn't a compiler in
>>>>>> the world for any language which will stop programmers from writing
>>>>>> incorrect code.
>>>>>
>>>>> Given the context of the discussion, pedantry seems appropriate.
>>>>>
>>>>> It's invalid C code because it doesn't declare rand() and printf(),
>>>>> correctable by adding `#include <stdlib.h>` and `#include <stdio.h>`.
>>>>> (It also contains NO-BREAK SPACE characters, but that's that's just a
>>>>> Usenet formatting issue.)
>>>>>
>>>>> Other than that, a conforming C compiler is not required to diagnose
>>>>> the above code.  It does have undefined behavior, and a C compiler is
>>>>> likely to warn about it with appropriate warnings, but it does not
>>>>> violate any syntax rule or constraint.
>>>>
>>>> I say it does.
>>
>> That would have been the correct place to identify the syntax rule or
>> constraint you think it violates, and I have no idea why you failed to
>> do so.
>>
>>> If you're right, then gcc 13.2.0 and clang 16.0.0 have a bug.  Both
>>> compile the above code (once the required #include directives are added)
>>> without error, though clang prints a couple of optional warnings.  I used
>>> "-std=c17 -pedantic-errors" with both compilers.  (With "-Wall", gcc
>>> prints warnings similar to the ones clang prints without it.)
>>>
>>> What syntax rule or constraint does it violate?
>
> Yes, that is the question I was referring to. [...]

I did answer.  If you don't like my answer that's your
problem, not mine.

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Re: bart again (UCX64) James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-11-18 00:57 -0500
  Re: bart again (UCX64) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-11-18 05:44 -0800
    Re: bart again (UCX64) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-11-19 00:25 -0800
      Re: bart again (UCX64) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-11-19 13:08 -0800
        Re: bart again (UCX64) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-12-25 17:45 -0800
          Re: bart again (UCX64) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-12-25 21:12 -0800
          Re: bart again (UCX64) James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-12-27 20:14 -0500
            Re: bart again (UCX64) Julieta Shem <jshem@yaxenu.org> - 2023-12-27 23:22 -0300
              Re: bart again (UCX64) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2023-12-28 04:25 +0100
            Re: bart again (UCX64) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2023-12-28 04:22 +0100
            Re: bart again (UCX64) David Brown <david.brown@hesbynett.no> - 2023-12-28 09:12 +0100
              Re: bart again (UCX64) Paul Edwards <mutazilah@gmail.com> - 2023-12-28 16:31 +0800
      Re: bart again (UCX64) James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-11-19 19:03 -0500
        Re: bart again (UCX64) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-12-25 17:46 -0800

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