Re: [gnugo-devel] Extremely bad mistake

[SP LEE]

> SP Lee wrote:
> > Yes, I'm still learning the basics of the code, but I'm sure the
> > suicide reading is wrong in this case. I have made the variable
> > verbose=3.
> 
> Ah, that might explain things. Could it be that you have been fooled
> by the very incomplete RTRACE messages? I was thinking those were
> merely useless but maybe they should be considered directly harmful.
> 
> Would anybody mind if I just remove them? (Historically these may have
> been useful in the early development of the tactical reading but have
> been superseded by more advanced techniques and have not been
> maintained.)
> 
> > What I have traced is, from the moment gnugo was "considering attack
> > of C19", until gnugo checked A16 in is_suicide in board.c, where I
> > found board[41]=0 (A18 is empty). Of course, board[41] was 1 in the
> > early analysis stage, but I don't know yet when it was changed to 0.
> > Maybe somewhere it's not propagated through to the defense checking.
> > The tracing message showed " A16 would be suicide".
> 
> No, this doesn't sound right. It would be too fundamental to have
> passed unnoticed. I would rather suspect that the traces are
> misleading.
> 
> /Gunnar
> 

Actually I didn't mean the routine is_suicide is wrong. I'll try to find out 
why board[41]=0 while the attack of A18 is under analysis. Apparently GNUGO 
doesn't think A16 is the answer to A18.

SP Lee