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  • HHH(DD) does correctly reject its input as non-halting --- VERIFIEDFACT

    From olcott@polcott333@gmail.com to comp.theory,comp.lang.c,comp.lang.c++ on Thu Jun 12 10:30:05 2025
    From Newsgroup: comp.lang.c

    int DD()
    {
    int Halt_Status = HHH(DD);
    if (Halt_Status)
    HERE: goto HERE;
    return Halt_Status;
    }

    It is a verified fact that DD() *is* one of the forms
    of the counter-example input as such an input would
    be encoded in C. Christopher Strachey wrote his in CPL.

    // rec routine P
    // §L :if T[P] go to L
    // Return §
    // https://academic.oup.com/comjnl/article/7/4/313/354243
    void Strachey_P()
    {
    L: if (HHH(Strachey_P)) goto L;
    return;
    }

    https://academic.oup.com/comjnl/article-abstract/7/4/313/354243?redirectedFrom=fulltext


    It *is* a verified fact DD correctly simulated by HHH
    cannot possibly reach its own "return" statement
    final halt state.

    All of the above code is fully operational in this file https://github.com/plolcott/x86utm/blob/master/Halt7.c
    --
    Copyright 2025 Olcott "Talent hits a target no one else can hit; Genius
    hits a target no one else can see." Arthur Schopenhauer

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