Re: Every sufficiently competent C programmer knows --- Paraphrase of Sipser's agreement

On 3/15/2025 5:35 PM, dbush wrote:

On 3/15/2025 5:27 PM, olcott wrote:

 <MIT Professor Sipser agreed to ONLY these verbatim words 10/13/2022>
     If simulating halt decider H correctly simulates its input D
     until H correctly determines that its simulated D would never
     stop running unless aborted then
      H can abort its simulation of D and correctly report that D
     specifies a non-halting sequence of configurations.
</MIT Professor Sipser agreed to ONLY these verbatim words 10/13/2022>
 

 But he didn't agree to what you think he did:
 

 THIS IS EXACTLY AND PRECISELY WHAT I THINK HE DID AGREE TO
(It took me years to form this precise paraphrase)
 <Accurate Paraphrase>
If emulating termination analyzer H emulates its input
finite string D of x86 machine language instructions
according to the semantics of the x86 programming language
until H correctly determines that this emulated D cannot
possibly reach its own "ret" instruction in any finite
number of correctly emulated steps then
 H can abort its emulation of input D and correctly report
that D specifies a non-halting sequence of configurations.
</Accurate Paraphrase>