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From: jrbd@craycos.com (James Davies)
Newsgroups: comp.lang.misc
Subject: Re: Array references cannot be made optimal
Message-ID: <1990Nov20.213454.10879@craycos.com>
Date: 20 Nov 90 21:34:54 GMT
References: <1990Nov14.150535.25991@cs.umu.se> <13530:Nov1419:56:3790@kramden.acf.nyu.edu> <156@garth.UUCP>
Organization: Cray Computer Corporation
Lines: 21

>> If a program, or rather a computer, is restricted to
>> a finite number of states (which all modern computers are) then it's nothing
>> more than a finite automaton and therefore the halting problem for these
>> machines is solvable *in theory*.
>
>Right. It's also solvable in practice.

main(argc,argv) {

	int I_halt();

	if (I_halt(argv[0])) {
		while(1);
	} else {
		exit(0);
	}
}

Please write I_halt.  It should return 1 if its argument program
halts, 0 if it doesn't.  Feel free to consult books or notes,
other programmers, Nobel prize winners, etc.