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From: Mikko <mikko.levanto@iki.fi>
Newsgroups: comp.lang.c
Subject: Re: How do simulating termination analyzers work? (in C and C++)
Date: Thu, 19 Jun 2025 09:57:25 +0300
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On 2025-06-17 23:24:45 +0000, olcott said:

> void Infinite_Recursion()
> {
>    Infinite_Recursion();
>    return;
>   }
> 
> void Infinite_Loop()
>   {
>    HERE: goto HERE;
>    return;
>   }
> 
> void DDD()
>   {
>    HHH(DDD);
>    return;
>   }
> 
> When it is understood that HHH does simulate itself
> simulating DDD then any first year CS student knows
> that when each of the above are correctly simulated
> by HHH that none of them ever stop running unless aborted.
> (recursive simulation is similar to infinite recursion).
> 
> The same thing equally applies to these two, yet they may
> be  too difficult for a first year CS student.
> 
> int Sipser_D()
>   {
>    if (HHH(Sipser_D) == 1)
>      return 0;
>    return 1;
> }
> 
> int DD()
>   {
>    int Halt_Status = HHH(DD);
>    if (Halt_Status)
>      HERE: goto HERE;
>    return Halt_Status;
>   }
> 
> *Fully operational code*
> https://github.com/plolcott/x86utm/blob/master/Halt7.c

Your "fully operational code" uses non-standard extensions to
C language. It does not work and cannot be made to work in an
environment where it is not possible to read the machine code
of a function as data.

-- 
Mikko