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Op 15.jun.2024 om 17:23 schreef olcott:The code that "does the opposite" was never reachable byOn 6/15/2024 10:12 AM, Fred. Zwarts wrote:When asked what is a pathological program olcott replied:Op 15.jun.2024 om 16:48 schreef olcott:>On 6/15/2024 9:37 AM, Fred. Zwarts wrote:>>>
Is this the new definition of "pathological"?
*It is the same thing that I have been saying all along*
>
00 typedef void (*ptr)(); // pointer to void function
01
02 int HH(ptr P, ptr I);
03
04 void DDD(int (*x)())
05 {
06 HH(x, x);
07 return;
08 }
09
10 int main()
11 {
12 HH(DDD,DDD);
13 }
>
Line 12 main()
invokes HH(DDD,DDD); that simulates DDD()
>
*REPEAT UNTIL outer HH aborts*
Line 06 simulated DDD()
invokes simulated HH(DDD,DDD); that simulates DDD()
>
DDD correctly simulated by HH never reaches its own "return"
instruction and halts.
So, you agree that you are changing definitions.
Not at all. The original definition still applies when it
is made more generic.
>
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 }
>
D correctly simulated by H has isomorphic behavior to DDD
correctly simulated by HH, both get stuck in recursive
simulation.
>
Op 14.jun.2024 om 21:18 schreef olcott:For any program H that might determine whether programs halt, aNo he defines a "pathological" program as a program that calls H.
"pathological" program D, called with some input, can pass its own
source and its input to H and then specifically do the opposite of what
H predicts D will do. No H can exist that handles this case.
All words about doing the opposite of what H predicts, have disappeared.
Everyone sees the difference, but he is stuck is rebuttal mode and denies the change of definition.
His only excuse is that in both cases a recursive simulation is seen, but that is not the point.The input does not halt and deciders are only accountable
He had already proved earlier that in
int main()
{
return H(main, 0);
}
H produces a false negative, because main halts, whereas H reports
non-halting. No relation with doing the opposite of what H predicts.--
This happens for DDD as well. Just a false negative. No relation with doing the opposite of what H predicts.
Even in the case of D, it is just a false negative, because even olcott admits that his simulation does not process the part where D does the opposite of what H predicts.
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