Sujet : Will Paypal $10 to the first person finding a valid counter-example
De : polcott333 (at) *nospam* gmail.com (olcott)
Groupes : comp.lang.c comp.lang.c++Date : 23. May 2024, 20:00:26
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <v2o3ob$1st5s$1@dont-email.me>
User-Agent : Mozilla Thunderbird
typedef int (*ptr)(); // ptr is pointer to int function in C
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 above template refers to an infinite set of H/D pairs where D is
correctly simulated by pure function H. This was done because many
reviewers used the shell game ploy to endlessly switch which H/D pair
was being referred to. Every H returns the meaningless integer 56.
*Pure Function Defined*
(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#*Correct Simulation Defined*
This is provided because many reviewers had a different
notion of correct simulation that diverges from this notion.
A simulator is an x86 emulator that correctly emulates at least one
of the x86 instructions of D in the order specified by the x86
instructions of D.
This may include correctly emulating the x86 instructions of H in the
order specified by the x86 instructions of H thus calling H(D,D) in
recursive simulation.
*Execution Trace*
Line 11: main() invokes H(D,D); H(D,D) simulates lines 01, 02, and 03
of D. This invokes H(D,D) again to repeat the process in endless
recursive simulation.
Will Paypal $10 to the first person finding a valid counter-example
where D correctly simulated by pure function H reaches is own line 06
and halts. This offer expires after 30 days. This offer only applies to
the first valid counter-example. This offer may be extended.
-- Copyright 2024 Olcott "Talent hits a target no one else can hit; Geniushits a target no one else can see." Arthur Schopenhauer