Re: How could HHH report on the behavior of its caller?

On 5/14/25 11:02 PM, olcott wrote:

On 5/14/2025 9:54 PM, Richard Damon wrote:

On 5/14/25 9:30 PM, olcott wrote:

void DDD()
{
   HHH(DDD);
   return;
}
>
int main()
{
   DDD();
}
>
If HHH cannot report on the behavior of its caller
because this is a ridiculous requirement then how
can HHH report on the direct execution of DDD()
(AKA its caller).
>

>
Because it is given the code of DDD, and thus doesn't need to know about "It caller"
>

 Unless it does know about its caller
The only directly executed DDD() that actually exists
no HHH can possibly know about any directly executed DDD().
 

So, how does it know that?
How does that knowledge affect the answer?
And no, it isn't the only directly executed DDD that exists, as programs are not "use once".
So, if your claim is that a Halt Decider just can't know the behavior of the direct execution of its input for any input, then you are just saying that the problme is logically impossible, and thus saying it can't be done is just a truism.
If you say it just can't handle this particular input, that is why a correct Halt Decider can't exist, we can make an input it can't determine.
Now, of course we can determine the behavior of any input, as that is what a UTM does, it recreates the full behavior from a description. The only proglem is a Halt Decider isn't supposed to reproduce the behavior, just decide on it, and thus can't just use simulation, which actually makes your concept broken.
THere is no such machine as a machine that both correct Halt Decides on its input and also correctly simulates that input, as the requirements are actually contradictory, so a "Simulating Halt Decider" based on being the correct simulator itself is just a category error.