Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Crafty Source is a two edged weapon

Author: Jürgen Hartmann

Date: 06:43:21 02/17/99

Go up one level in this thread


Bravo, I find that brilliant. An ideal protection. Force people to understand
what you are doing.

Jürgen

>changed in the wrong places, the SMP search breaks in subtle ways.  It causes
>me a lot of grief as when I make changes and don't check these 'tripwires' I
>trigger them myself and do a lot of debugging.
>
>
>I've done one thing already that I suppose won't hurt to reveal.  Way back in
>the SMP development, I thought about this problem.  And I made a couple of
>'assumptions' that are wrong about some things I do in the SMP search.  These
>'wrong' things can be avoided by subtle programming things, but if the code is

>I won't say more, other than that at least 'copying' the SMP code line for line
>is guaranteed to produce two nice 'glitches' that will produce amusement when
>they show up.  But they are subtle.  I only wish it was 'easy' to make the
>'copy' act up upon demand... but the bugs are more subtle than that,
>unfortunately.
>
>If someone studies the SMP code _very_ carefully, the problems can be exposed.
>But that is the point...  because at least they have to understand the algorithm
>to make it usable, or else run the risk of some 'interesting behavior'...  So I
>have taken one step at least, but only WRT the SMP stuff.  (one of these
>problems was simply a bug that I had to find before the current SMP algorithm
>was functional in early 15.x versions.  But it was cute enough that I decided
>that this was the 'perfect' protective mechanism, and I just chose to fix the
>'symptom' rather than the actual problem.)
>
>Let's just see what happens...



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.