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From: Mikko <mikko.levanto@iki.fi>
Newsgroups: comp.theory
Subject: Re: DDD correctly emulated by HHH is correctly rejected as non-halting.
Date: Fri, 12 Jul 2024 11:27:10 +0300
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On 2024-07-11 14:02:52 +0000, olcott said:

> On 7/11/2024 1:22 AM, Mikko wrote:
>> On 2024-07-10 15:03:46 +0000, olcott said:
>> 
>>> typedef void (*ptr)();
>>> int HHH(ptr P);
>>> 
>>> void DDD()
>>> {
>>>    HHH(DDD);
>>> }
>>> 
>>> int main()
>>> {
>>>    HHH(DDD);
>>> }
>>> 
>>> We stipulate that the only measure of a correct emulation
>>> is the semantics of the x86 programming language. By this
>>> measure when 1 to ∞ steps of DDD are correctly emulated by
>>> each pure function x86 emulator HHH (of the infinite set
>>> of every HHH that can possibly exist) then DDD cannot
>>> possibly reach past its own machine address of 0000216b
>>> and halt.
>> 
>> For every instruction that the C compiler generates the x86 language
>> specifies an unambiguous meaning, leaving no room for "can".
>> 
> 
> then DDD cannot possibly reach past its own machine
> address of 0000216b and halt.

As I already said, there is not room for "can". That means there is
no room for "cannot", either. The x86 semantics of the unshown code
determines unambigously what happens.

-- 
Mikko