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From: olcott <polcott333@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: D correctly simulated by pure function H cannot possibly reach
 its, own line 06
Date: Sun, 26 May 2024 11:54:51 -0500
Organization: A noiseless patient Spider
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On 5/26/2024 11:04 AM, Mikko wrote:
> On 2024-05-26 13:12:08 +0000, olcott said:
>> I had to make the subject line of the thread a little less accurate
>> so that people could get the gist of what I was saying. Now I have
>> made it precise.
> 
> Subject lines typically are as they are limited to one line. That's
> not a problem.
> 

*I finally have much better words*

typedef int (*ptr)();  // ptr is pointer to int function in C
00       int H(ptr p, ptr i);
01       int D(ptr p)
02       {
03         int Halt_Status = H(p, p);
04         if (Halt_Status)
05           HERE: goto HERE;
06         return Halt_Status;
07       }
08
09       int main()
10       {
11         H(D,D);
12         return 0;
13       }

When we see that D correctly simulated by pure simulator H would remain
stuck in recursive simulation then we also know that D never reaches its
own line 06 and halts in less than an infinite number of correctly
simulated steps.

This means that D correctly simulated by pure function H also never
reaches it own line 06 and halts.


-- 
Copyright 2024 Olcott "Talent hits a target no one else can hit; Genius
hits a target no one else can see." Arthur Schopenhauer