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From: "Fred. Zwarts" <F.Zwarts@HetNet.nl>
Newsgroups: comp.theory,sci.logic
Subject: Re: Every D correctly simulated by H never reaches its final state
 and halts
Date: Fri, 17 May 2024 09:25:52 +0200
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Op 17.mei.2024 om 03:15 schreef olcott:
> The following is self-evidently true on the basis of the
> semantics of the C programming language.
> 
> typedef int (*ptr)();  // ptr is pointer to int function
> 00 int H(ptr x, ptr x);
> 01 int D(ptr x)
> 02 {
> 03   int Halt_Status = H(x, x);
> 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 }
> 
> In the above case a simulator is an x86 emulator that correctly
> emulates at least one of the x86 instructions of D in the order
> specified by the x86 instructions of D.
> 
> This may include correctly emulating the x86 instructions of H
> in the order specified by the x86 instructions of H thus calling
> H(D,D) in recursive simulation.
> 
> Any H/D pair matching the above template where
> D(D) is simulated by the same H(D,D) that it calls
> cannot possibly reach its own line 06 and halt.
> 
> *This is a simple software engineering verified fact*
> 

Note that olcott defines 'verified fact' as 'proven fact', but he is 
unable to show the proof. So, it must be read as 'my belief'.