Path: ...!news.misty.com!weretis.net!feeder9.news.weretis.net!news.nk.ca!rocksolid2!i2pn2.org!.POSTED!not-for-mail From: Richard Damon Newsgroups: comp.theory Subject: Re: Every D(D) simulated by H presents non-halting behavior to H ### Date: Mon, 13 May 2024 20:30:12 -0400 Organization: i2pn2 (i2pn.org) Message-ID: References: <-5Gdnf-nQvstC6b7nZ2dnZfqnPadnZ2d@brightview.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Tue, 14 May 2024 00:30:12 -0000 (UTC) Injection-Info: i2pn2.org; logging-data="1019135"; mail-complaints-to="usenet@i2pn2.org"; posting-account="diqKR1lalukngNWEqoq9/uFtbkm5U+w3w6FQ0yesrXg"; User-Agent: Mozilla Thunderbird Content-Language: en-US X-Spam-Checker-Version: SpamAssassin 4.0.0 In-Reply-To: Bytes: 4048 Lines: 76 On 5/13/24 7:00 PM, olcott wrote: > On 5/13/2024 5:20 PM, immibis wrote: >> On 13/05/24 16:43, olcott wrote: >>> On 5/13/2024 4:14 AM, Mikko wrote: >>>> On 2024-05-13 04:54:30 +0000, immibis said: >>>> >>>>> On 10/05/24 19:55, Alan Mackenzie wrote: >>>>>> [ Followup-To: set ] >>>>>> >>>>>> In comp.theory olcott wrote: >>>>>> >>>>>> [ .... ] >>>>>> >>>>>> I've tried out your much spammed code on GCC (see below).  It is >>>>>> clear >>>>>> you have never built or run this code, which ironically can't >>>>>> reach Line >>>>>> 06.  It can't even reach line 00. >>>>>> >>>>>>> Richard tried to get away with D never simulated by H as an example >>>>>>> of D simulated by H: >>>>>> >>>>>>> Message-ID: >>>>>>> On 5/1/2024 7:28 PM, Richard Damon wrote: >>>>>> >>>>>>> *That people say they know I am wrong yet will not show the >>>>>>> detailed* >>>>>>> *steps of how I am wrong indicates that they are probably liars* >>>>>> >>>>>> You have said, or at least implied that your code fragment is >>>>>> runnable. >>>>>> I think you are the liar, here. >>>>>> >>>>>>> 00 int H(ptr x, ptr x)  // ptr is pointer to int function >>>>>>> 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 } >>>>>> >>>>>> >>>>>> .  These are the diagnostics generated by GCC: >>>>>> >>>>> And the halting problem is about Turing machines, anyway. >>>> >>>> Not necessarily. The same question can be asked about different >>>> machines. >>>> The restriction to Turing machines is just one way to ensure that the >>>> problem is well defined. >>>> >>> >>> Well put. All computable functions even if written in C. >>> >> C makes the problem more complicated and easier to cheat and harder to >> notice cheating. If you haven't cheated, > > *Not if you spend two years researching this and discussing this* > > https://en.wikipedia.org/wiki/Computable_function > in C is simply a > https://en.wikipedia.org/wiki/Pure_function Nope. > >> then all programs can be converted to Turing machines. Turing machines >> are long and boring, however, if you haven't cheated then it should be >> obvious how they could be converted if someone wanted to spend the time. >