Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail
From: Richard Heathfield <rjh@cpax.org.uk>
Newsgroups: comp.lang.c
Subject: Re: DD simulated by HHH cannot possibly halt (Halting Problem)
Date: Sat, 5 Apr 2025 23:14:23 +0100
Organization: Fix this later
Lines: 51
Message-ID: <vssa00$3b2j0$1@dont-email.me>
References: <vsnchj$23nrb$2@dont-email.me> <vsngo6$26agq$1@dont-email.me>
 <vsnh44$26c94$3@dont-email.me> <vsnht7$26agq$2@dont-email.me>
 <vsnlvv$2h8pt$1@dont-email.me> <vsnnb5$2g4cd$2@dont-email.me>
 <vsnnug$2h8pt$2@dont-email.me> <vsnou2$2g4cd$5@dont-email.me>
 <vspqmt$o89d$1@dont-email.me> <vsq97g$19eo9$1@dont-email.me>
 <vsqhov$1hl94$1@dont-email.me> <vsqmth$1mglg$2@dont-email.me>
 <vsrk17$2le7u$1@dont-email.me> <vsrlh7$2n0kg$1@dont-email.me>
 <vsrrnl$2ssgf$3@dont-email.me> <vsrtp0$2sut0$2@dont-email.me>
 <vsrun6$2ssgf$5@dont-email.me> <vsrvao$2sut0$3@dont-email.me>
 <vsrvsd$317k3$1@dont-email.me> <vss3se$35rqb$1@dont-email.me>
 <vss6qe$375du$7@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Date: Sun, 06 Apr 2025 00:14:24 +0200 (CEST)
Injection-Info: dont-email.me; posting-host="dbe7ec1ac8ffd7a60b5ada94cfd55d95";
	logging-data="3508832"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX18FkBtqlI6TBt2ZPZ1EPU+NoXuH/VKn6fwFPAxTlAsRqw=="
User-Agent: Mozilla Thunderbird
Cancel-Lock: sha1:8hNDynCYieoff5hRMAKfm3j0AAU=
Content-Language: en-GB
In-Reply-To: <vss6qe$375du$7@dont-email.me>
Bytes: 3232

On 05/04/2025 22:20, olcott wrote:
> On 4/5/2025 3:30 PM, Richard Heathfield wrote:
>> On 05/04/2025 20:21, olcott wrote:
>>> On 4/5/2025 2:12 PM, Richard Heathfield wrote:
>>>> On 05/04/2025 20:01, olcott wrote:
>>>>> As any C programmer can see DDD simulated by HHH would cause
>>>>> any correct simulator to get stuck in recursive simulation
>>>>
>>>> As any C programmer can see, any C compiler is free to reject 
>>>> your code, 
>>>
>>> typedef void (*ptr)();
>>> int HHH(ptr P);
>>>
>>> void DDD()
>>> {
>>>    HHH(DDD);
>>>    return;
>>> }
>>>
>>> The above code is correct to the extent that some
>>> HHH is defined somewhere, so it seems that you are
>>> wrong
>>
>> No, you just don't know what I'm talking about. That doesn't 
>> surprise me, of course.
>>
>> I'm talking about your HHH code. Any conforming compiler can 
>> reject your assembly language inserts.
>>
> 
> I am not taking about that code.

Yes, you are. And I quote: "As any C programmer can see DDD 
simulated by HHH"

> This post has only been about a hypothetical
> HHH that simulates its input.

If you don't wish to be misunderstood, it would be a good idea 
for you to learn to express yourself more clearly. For example, 
you could choose better names for your hypothetical functions to 
avoid confusion between them and functions for which you've 
published the code on github.

-- 
Richard Heathfield
Email: rjh at cpax dot org dot uk
"Usenet is a strange place" - dmr 29 July 1999
Sig line 4 vacant - apply within