Re: Every D(D) simulated by H presents non-halting behavior to H ###

On 2024-05-22 14:59:24 +0000, olcott said:

On 5/22/2024 3:50 AM, David Brown wrote:

On 21/05/2024 22:13, Keith Thompson wrote:

David Brown <david.brown@hesbynett.no> writes:
[...]

However, my point was that the common excuse of "I hate this crime so
much I lashed out" is not a valid excuse.

[...]
 And you could have made that point without accompanying it by a long
article about various kinds of child abuse in a newsgroup that's
supposed to be about C.
 You didn't have to let yourself be trolled.
 

 I don't consider James' post to be trolling.  But of course that in itself does not mean it is appropriate to reply here.  However, I replied to that post in the group (rather than email) because it seemed to me that a point I had made previously needed clarification.
 As has been pointed out by others, topicality in this thread was doomed from the first post.  I'd be happier if Olcott had never cross-posted here, but we can't change that.
 

 *Someone could simply answer the question instead of*
*spending countless messages on dodging the question*
 For every H/D pair matching the following template where
H is a pure function:
 Does any D correctly simulated by H reach its own line 06 and
halt or does the fact that D remains stuck in recursive simulation
prevent that?
 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       }
 It is trivial to see that for every H/D pair of the infinite
set of H/D pairs that match the above template that
 D correctly simulated by H cannot possibly reach its own final
state at line 06 and halt because D correctly simulated by
H remains stuck in recursive simulation.
 This provides the basis for simulating termination analyzer H to
correctly determine that the halting problem's counter-example
input D cannot possibly halt.

Someone already pointed out that the question is ill-posed (undefined
and insonsistently used symbols). No reason to expect any other answer.
--
Mikko