Re: D correctly simulated by H cannot possibly reach its own line 06 and halt

On 5/30/2024 4:54 PM, joes wrote:

Am Thu, 30 May 2024 09:55:24 -0500 schrieb olcott:
 

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       }
>
The left hand-side are line numbers of correct C code.
This code does compile and does conform to c17.
>
Everyone with sufficient knowledge of C can easily determine that D
correctly emulated by any *pure function* H (using an x86 emulator)
cannot possibly reach its own simulated final state at line 06 and halt.

Yeah, of course not, if H doesn’t halt.
 

To actually understand my words (as in an actual honest dialogue)
you must pay careful attention to every single word. Maybe you
had no idea that *pure functions* must always halt.
Or maybe you did not know that every computation that never reaches
its own final state *DOES NOT HALT* even if it stops running because
it is no longer simulated.
*Pure function*
(1) the function return values are identical for identical arguments
(*no variation with local static variables*, non-local variables,
mutable reference arguments or input streams, i.e., referential
transparency), and
(2) the function has no side effects (*no mutation of local static*
*variables*, non-local variables, mutable reference arguments or
input/output streams). https://en.wikipedia.org/wiki/Pure_function

Because this is a key piece of my life's work and my POD24 diagnosis
indicates that I am running out of time I intend to keep posting this
until I have three concurrences or one correct rebuttal.

 

--
Copyright 2024 Olcott "Talent hits a target no one else can hit; Genius
hits a target no one else can see." Arthur Schopenhauer