XPost: comp.theory, comp.lang.c++, comp.lang.c   
   From: polcott333@gmail.com   
      
   On 9/29/2025 8:42 PM, Richard Heathfield wrote:   
   > On 30/09/2025 02:29, olcott wrote:   
   >>>   
   >>   
   >> The instance of DD that HHH is simulating does call   
   >> an instance of HHH: dip shit.   
   >   
   > No, genius, it doesn't. DD isn't running, so it's in no position to call   
   > anything. Simulating a call is not the same as calling.   
   >   
      
   typedef int (*ptr)();   
   int HHH(ptr P);   
      
   int DD()   
   {   
      int Halt_Status = HHH(DD);   
      if (Halt_Status)   
        HERE: goto HERE;   
      return Halt_Status;   
   }   
      
   When DD is simulated by HHH according to the semantics of the   
   x86 language then *the finite string input to HHH does specify*   
      
   that HHH simulates DD and then simulates an instance of itself   
   simulating an instance of DD that calls yet another instance   
   of HHH in recursive simulation again.   
      
   *the finite string input to HHH does specify*   
   pick's up where Rice's theorem left off.   
      
   In computability theory, Rice's theorem states that   
   all non-trivial semantic properties of programs are   
   undecidable. A semantic property is one about the   
   program's behavior ...   
   https://en.wikipedia.org/wiki/Rice%27s_theorem   
      
   All Turing machine deciders only compute the mapping   
   from their finite string inputs to an accept state   
   or reject state on the basis that this input finite   
   string specifies a semantic or syntactic property.   
      
   --   
   Copyright 2025 Olcott "Talent hits a target no one else can hit; Genius   
   hits a target no one else can see." Arthur Schopenhauer   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)