Re: "Perfect" or "Provable" security both crypto and non-crypto?

From: Douglas A. Gwyn (DAGwyn_at_null.net)
Date: 09/14/04


Date: Mon, 13 Sep 2004 23:44:01 -0400

Sebastian Gottschalk wrote:
> The problem of finding the invariants of a loop under Hoare calculus is
> equivalent to the halting problem of a turing machine.

For *arbitrary* ("random") programs, sure, but not for
the vast majority of practical programs. And if during
program construction, the correctness checker warned of
a case that it could not readily verify, that would in
itself be an important warning that the code needs to
be examined; something is probably wrong with it.



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