Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: Mikko Newsgroups: comp.theory Subject: Re: Anyone with sufficient knowledge of C knows that DD specifies non-terminating behavior to HHH Date: Sun, 9 Feb 2025 11:48:28 +0200 Organization: - Lines: 67 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sun, 09 Feb 2025 10:48:29 +0100 (CET) Injection-Info: dont-email.me; posting-host="be41167b37f4913cfc58d1b1d5628bdd"; logging-data="588638"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/rrV0f/FFlQvXG437FFILk" User-Agent: Unison/2.2 Cancel-Lock: sha1:lNtJalCwpTJqZLv3dXMR7UHO9IU= Bytes: 3227 On 2025-02-08 14:43:53 +0000, olcott said: > On 2/8/2025 3:54 AM, Fred. Zwarts wrote: >> Op 08.feb.2025 om 00:13 schreef olcott: >>> Experts in the C programming language will know that DD >>> correctly simulated by HHH cannot possibly reach its own >>> "if" statement. >> >> Yes, it demonstrates the incapability of HHH to correctly determine the >> halting behaviour of DD >> >>> >>> The finite string DD specifies non-terminating recursive >>> simulation to simulating termination analyzer HHH. This >>> makes HHH necessarily correct to reject its input as >>> non-halting. >> >> The finite string defines one behaviour. This finite string, when given >> to an X86 processor shows halting behaviour. This finite string,when >> given to a world class simulator, shows halting behaviour. Only HHH >> fails to see this proven halting behaviour. So it proves the failure of >> HHH. >> HHH aborts the simulation on unsound grounds one cycle before the >> simulation would terminate normally. >> >>> >>> typedef void (*ptr)(); >>> int HHH(ptr P); >>> >>> int DD() >>> { >>>    int Halt_Status = HHH(DD); >>>    if (Halt_Status) >>>      HERE: goto HERE; >>>    return Halt_Status; >>> } >>> >>> int main() >>> { >>>    HHH(DD); >>> } >>> >>> https://www.researchgate.net/ >>> publication/369971402_Simulating_Termination_Analyzer_H_is_Not_Fooled_by_Pathological_Input_D >>> >>> >>> https://github.com/plolcott/x86utm/blob/master/Halt7.c >>> has fully operational HHH and DD >>> >>> The halting problem has always been a mathematical mapping >>> from finite strings to behaviors. >> >> Yes. And the behaviour of this finite string has been proven to show >> halting behaviour. Only Olcott's HHH fails to see it. >> His misunderstanding is that he thinks that the behaviour defined by >> the finite string depends on the simulator. > > When DD calls HHH(DD) in recursive simulation it is a > verified fact that DD cannot possibly halt. The word "cannot" is not compatible with the meaning of the word "fact". That "DD cannot possibly halt" is not a fact. A fact may be that "DD has not halted in any test so far". -- Mikko