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On 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:Not at all. The original definition still applies when itOn 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.
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.
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.
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