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Subject: Re: Problem searching too deep!

Author: Daniel Clausen

Date: 07:45:10 05/28/02

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On May 28, 2002 at 09:30:48, Sune Fischer wrote:

>"careless" :)

Maybe that's not the appropriate word, but my native language is not English, so
please bear with me. :)


>Hmm, I don't know. I need to extend ~100 plies(!!) to get a crash for a total
>of 200 plies search! Can you come up with any kind of position that would even
>slightly challenge this limit?

I just "play it safe" in my engine. It's just a simple if-statement which most
likely costs almost nothing. I don't _have_ to think about what might happen in
some obscure position. :) I've learned that "I'm sure that this won't happen"
happens more than people think.


>I also have the maximum number of pseudo legal moves set to 255, this must be
>a potential bug too then?

I think that the max number of legal moves is around 220. It's very well
possible that the number of pseudo legal moves is above 255. So to answer your
question: yes =)


>Well I'm not going to check before adding a move if there is still room, call
>me careless if you must ;)

Feel free. :)

Hint: Another possibility would be to check at the end of movegen how many moves
you added in total. If your movegen gets a 'move_t *' and increments this
pointer each time you add a move, it's a simple subtraction to find out the
number of generated moves. (and an if-statement of course for the test :)


>These are the only known limitations I have, anything else shouldn't crash if
>the position is technical legal.

[now getting real picky :)]

If the position is technically illegal, your engine shouldn't accept it,
especially when it 'destroys' your internal data structures.

Rule: When an application crashes because of user input, it's _always_ the
application's fault - one way or the other.

Sargon (very picky today :)



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