Path: ...!weretis.net!feeder9.news.weretis.net!news.quux.org!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail
From: "Fred. Zwarts" <F.Zwarts@HetNet.nl>
Newsgroups: comp.theory
Subject: Re: Anyone with sufficient knowledge of C knows that DD specifies
 non-terminating behavior to HHH
Date: Tue, 18 Feb 2025 15:11:39 +0100
Organization: A noiseless patient Spider
Lines: 115
Message-ID: <vp24ev$1namo$1@dont-email.me>
References: <vo6420$3mpmf$1@dont-email.me> <vo7be3$jug$1@dont-email.me>
 <vo7r8d$36ra$3@dont-email.me> <vo9ura$i5ha$1@dont-email.me>
 <voahc5$m3dj$8@dont-email.me> <vocdo9$14kc0$1@dont-email.me>
 <vocpl7$16c4e$4@dont-email.me> <vof56u$1n9k0$1@dont-email.me>
 <vofnj2$1qh2r$2@dont-email.me> <vohrmi$29f46$1@dont-email.me>
 <vojs0e$2oikq$4@dont-email.me> <vokdha$2rcqi$1@dont-email.me>
 <vom1fr$34osr$1@dont-email.me> <von0iq$3d619$1@dont-email.me>
 <vondj5$3ffar$1@dont-email.me> <vopke4$3v10c$1@dont-email.me>
 <vosn00$jd5m$1@dont-email.me>
 <f9a0a18d52ac35171173e0c60c9062e03343ad68@i2pn2.org>
 <vote0u$nf28$1@dont-email.me>
 <3b8a5f4be53047b2a6c03f9678d0253e137d3c40@i2pn2.org>
 <votn1l$pb7c$1@dont-email.me>
 <5cd9bc55c484f10efd7818ecadf169a11fcc58e1@i2pn2.org>
 <votq5o$ppgs$1@dont-email.me> <vouu57$12hqt$3@dont-email.me>
 <vp1jkg$1kstl$1@dont-email.me> <vp1qp1$1m05h$2@dont-email.me>
 <442891e4193f52206ec1b8481f5c2688de58b305@i2pn2.org>
 <vp22fi$1n991$3@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Date: Tue, 18 Feb 2025 15:11:49 +0100 (CET)
Injection-Info: dont-email.me; posting-host="6a355507216d4f08503b9cb7c992fe34";
	logging-data="1813208"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX1+NM9K0apyfSd96PWuTAr0l"
User-Agent: Mozilla Thunderbird
Cancel-Lock: sha1:ogrKdRxf/rWiJ0Exw/DQTApwKTo=
Content-Language: nl, en-GB
In-Reply-To: <vp22fi$1n991$3@dont-email.me>
Bytes: 7031

Op 18.feb.2025 om 14:37 schreef olcott:
> On 2/18/2025 6:25 AM, Richard Damon wrote:
>> On 2/18/25 6:26 AM, olcott wrote:
>>> On 2/18/2025 3:24 AM, Mikko wrote:
>>>> On 2025-02-17 09:05:42 +0000, Fred. Zwarts said:
>>>>
>>>>> Op 16.feb.2025 om 23:51 schreef olcott:
>>>>>> On 2/16/2025 4:30 PM, joes wrote:
>>>>>>> Am Sun, 16 Feb 2025 15:58:14 -0600 schrieb olcott:
>>>>>>>> On 2/16/2025 2:02 PM, joes wrote:
>>>>>>>>> Am Sun, 16 Feb 2025 13:24:14 -0600 schrieb olcott:
>>>>>>>>>> On 2/16/2025 10:35 AM, joes wrote:
>>>>>>>>>>> Am Sun, 16 Feb 2025 06:51:12 -0600 schrieb olcott:
>>>>>>>>>>>> On 2/15/2025 2:49 AM, Mikko wrote:
>>>>>>>>>>>>> On 2025-02-14 12:40:04 +0000, olcott said:
>>>>>>>>>>>>>> On 2/14/2025 2:58 AM, Mikko wrote:
>>>>>>>>>>>>>>> On 2025-02-14 00:07:23 +0000, olcott said:
>>>>>>>>>>>>>>>> On 2/13/2025 3:20 AM, Mikko wrote:
>>>>>>>>>>>>>>>>> On 2025-02-13 04:21:34 +0000, olcott said:
>>>>>>>>>>>>>>>>>> On 2/12/2025 4:04 AM, Mikko wrote:
>>>>>>>>>>>>>>>>>>> On 2025-02-11 14:41:38 +0000, olcott said:
>>>>>>>
>>>>>>>>>>>>>> DD  correctly simulated by HHH cannot possibly terminate 
>>>>>>>>>>>>>> normally.
>>>>>>>>>>>>>
>>>>>>>>>>>>> That claim has already shown to be false. Nothing above 
>>>>>>>>>>>>> shows that
>>>>>>>>>>>>> HHH does not return 0. If it does DD also returns 0.
>>>>>>>>>>>> When we are referring to the above DD simulated by HHH and not
>>>>>>>>>>>> trying to get away with changing the subject to some other DD
>>>>>>>>>>>> somewhere else
>>>>>>>>>>> such as one that calls a non-aborting version of HHH
>>>>>>>>>>>
>>>>>>>>>>>> then anyone with sufficient knowledge of C programming knows 
>>>>>>>>>>>> that no
>>>>>>>>>>>> instance of DD shown above simulated by any corresponding 
>>>>>>>>>>>> instance
>>>>>>>>>>>> of HHH can possibly terminate normally.
>>>>>>>>>>> Well, then that corresponding (by what?) HHH isn’t a decider.
>>>>>>>>>> I am focusing on the isomorphic notion of a termination analyzer.
>>>>>>>>> (There are other deciders that are not termination analysers.)
>>>>>>>>>
>>>>>>>>>> A simulating termination analyzer correctly rejects any input 
>>>>>>>>>> that
>>>>>>>>>> must be aborted to prevent its own non-termination.
>>>>>>>>> Yes, in particular itself is not such an input, because we 
>>>>>>>>> *know* that
>>>>>>>>> it halts, because it is a decider. You can’t have your cake and 
>>>>>>>>> eat it
>>>>>>>>> too.
>>>>>>>> I am not even using the confusing term "halts".
>>>>>>>> Instead I am using in its place "terminates normally".
>>>>>>>> DD correctly simulated by HHH cannot possibly terminate normally.
>>>>>>> What’s confusing about „halts”? I find it clearer as it does not 
>>>>>>> imply
>>>>>>> an ambiguous „abnormal termination”. How does HHH simulate DD
>>>>>>> terminating abnormally, then? Why doesn’t it terminate abnormally
>>>>>>> itself?
>>>>>>> You can substitute the term: the input DD to HHH does not need to be
>>>>>>> aborted, because the simulated decider terminates.
>>>>>>>
>>>>>>
>>>>>> typedef void (*ptr)();
>>>>>> int HHH(ptr P);
>>>>>>
>>>>>> int DD()
>>>>>> {
>>>>>>   int Halt_Status = HHH(DD);
>>>>>>   if (Halt_Status)
>>>>>>     HERE: goto HERE;
>>>>>>   return Halt_Status;
>>>>>> }
>>>>>>
>>>>>> int main()
>>>>>> {
>>>>>>   HHH(DD);
>>>>>> }
>>>>>>
>>>>>> Every simulated input that must be aborted to
>>>>>> prevent the non-termination of HHH is stipulated
>>>>>> to be correctly rejected by HHH as non-terminating.
>>>>>>
>>>>> A very strange and invalid stipulation.
>>>>
>>>> It merely means that the words do not have their ordinary meaning.
>>>>
>>>
>>> Unless HHH(DD) aborts its simulation of DD itself cannot possibly 
>>> terminate normally. Every expert in the C programming language
>>> can see this. People that are not experts get confused by the loop
>>> after the "if" statement.
>>>
>>
>> So? Since it does that, it needs to presume that the copy of itself it 
>> sees called does that.
>>
> 
> Not at all. Perhaps your technical skill is much more woefully
> deficient than I ever imagined.
> 
> Here is the point that you just missed Unless the first HHH
> that sees the non-terminating pattern aborts its simulation
> none of them do because they all have the exact same code.
> 
> 

The point Olcott misses is that if the non-terminating HHH is changed to 
abort the simulation, the program is changed. He does not understand 
that a modification of a program makes a change. Such a change modifies 
the behaviour of the program. The non-termination behaviour has 
disappeared with this change and only remains in his dreams. After this 
change, the simulation would terminate normally and HHH should no longer 
abort. But it does, because the code that detects the 'special 
condition' has a bug, which makes that it does not see that the program 
has been changed into a halting program.