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From: olcott <polcott333@gmail.com>
Newsgroups: comp.theory
Subject: Re: Every sufficiently competent C programmer knows
Date: Tue, 11 Mar 2025 08:26:55 -0500
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On 3/11/2025 5:01 AM, Richard Heathfield wrote:
> On 11/03/2025 08:55, Fred. Zwarts wrote:
>> Op 11.mrt.2025 om 00:41 schreef olcott:
>>> typedef void (*ptr)();
>>> int HHH(ptr P);
>>>
>>> void Infinite_Loop()
>>> {
>>>    HERE: goto HERE;
>>>    return;
>>> }
>>>
>>> void Infinite_Recursion()
>>> {
>>>    Infinite_Recursion();
>>>    return;
>>> }
>>>
>>> void DDD()
>>> {
>>>    HHH(DDD);
>>>    return;
>>> }
>>>
>>> int DD()
>>> {
>>>    int Halt_Status = HHH(DD);
>>>    if (Halt_Status)
>>>      HERE: goto HERE;
>>>    return Halt_Status;
>>> }
>>>
>>> That when HHH correctly emulates N steps of the
>>> above functions that none of these functions can
>>> possibly reach their own "return" instruction
>>> and terminate normally.
>>> >
>>>
>>> Since HHH does see that same pattern that competent
>>> C programmers see it correctly aborts its emulation
>>> and rejects these inputs as non terminating. 
>>
>> All competent C programmers see that HHH correctly reports that it 
>> cannot possibly reach the 'return' instruction.
> 
> First, my credentials. I've been programming in C for over 35 years; I'm 
> told that my book on C has been used on two undergraduate Comp Sci 
> courses (one in the States and one in the UK); and I have my Knuth 
> cheque. I don't claim to be any kind of programming guru, but I hope I 
> do not overstate the case when I suggest that I can be regarded as 
> competent not just as a programmer but specifically in the C language.
> 
> And yet I can't even /see/ HHH, let alone judge what it does or does not 
> do correctly. All I see is a call to it.
> 

It is stipulated that HHH correctly emulates N
steps of the x86 machine code of its input functions.
This may or may not include HHH emulating itself
emulating an input.

> And ld concurs. It can't see HHH either.
> 
> I suggest that Mr Olcott should supply the missing source code if he 
> wishes to be taken seriously.
> 

Not required for the above thought experience where
every relevant behavior has been fully specified. This
is merely another lame attempt on your part to perpetually
dodge the point.

-- 
Copyright 2025 Olcott "Talent hits a target no one else can hit; Genius
hits a target no one else can see." Arthur Schopenhauer