Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: dbush Newsgroups: comp.theory,comp.lang.c,comp.lang.c++ Subject: Re: DD correctly emulated by HHH --- Totally ignoring invalid rebuttals Date: Mon, 3 Mar 2025 22:33:19 -0500 Organization: A noiseless patient Spider Lines: 39 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Tue, 04 Mar 2025 04:33:18 +0100 (CET) Injection-Info: dont-email.me; posting-host="78d928a9a400af2e1a99aa5e831e2fe9"; logging-data="1667001"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/T99LjO7BFDL3fEfojHaPO" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:PsTUSnFNbYC/rnLogiF0FSMETJc= Content-Language: en-US In-Reply-To: Bytes: 2406 On 3/3/2025 10:07 PM, olcott wrote: > int DD() > { >   int Halt_Status = HHH(DD); >   if (Halt_Status) >     HERE: goto HERE; >   return Halt_Status; > } > > _DD() > [00002133] 55         push ebp      ; housekeeping > [00002134] 8bec       mov ebp,esp   ; housekeeping > [00002136] 51         push ecx      ; make space for local > [00002137] 6833210000 push 00002133 ; push DD > [0000213c] e882f4ffff call 000015c3 ; call HHH(DD) > [00002141] 83c404     add esp,+04 > [00002144] 8945fc     mov [ebp-04],eax > [00002147] 837dfc00   cmp dword [ebp-04],+00 > [0000214b] 7402       jz 0000214f > [0000214d] ebfe       jmp 0000214d > [0000214f] 8b45fc     mov eax,[ebp-04] > [00002152] 8be5       mov esp,ebp > [00002154] 5d         pop ebp > [00002155] c3         ret > Size in bytes:(0035) [00002155] > > DD correctly emulated by HHH cannot possibly > reach its own "ret" instruction and terminate normally. > > The only valid rebuttal is to show all of the steps of > exactly how DD correctly emulated by HHH reaches its > own "ret" instruction. > Suppose we accept that HHH is able to correctly determine that replacing the code of HHH with an unconditional simulator and running HHH(DD) will not halt. Then what?