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On 5/30/2024 4:54 PM, joes wrote:And that is about the ACTUAL EXECUTION of the program, not its partial simulation.Am Thu, 30 May 2024 09:55:24 -0500 schrieb olcott:To actually understand my words (as in an actual honest dialogue)
>typedef int (*ptr)(); // ptr is pointer to int function in CYeah, of course not, if H doesn’t halt.
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.
>
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.
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