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============================== My email: jotes@go2.pl



Pigeon 1.51 fix - UCI chess engine

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About version 1.51:
Fixed timing logic under 40/4 and 40/25 time controls (thanks to Graham Banks for pointing out the error!)
Fixed delay when setting a new position at the start of a move.

Pigeon 1.51 fix
I discovered a huge bug for it on my non popcount hardware recently manifesting in weird evals directly after start positions. Even weirder it seems only to happen if the start position is below 12 plies (I used 6 plies).
This happened in around 1/3 of all games in 40/2 test games and resulted sometimes in plain piece blunders, at around move 7 the weird evals disappeared but the damage was done.
Finally Martin Sedlak (Cheng) looked into it and found something with UB sanitizer. It seems SquareBit indexing was screwed up.
Martin sent me a quick fix (also with a hack for easier compiling in Windows) and really my tests showed the error was gone.

Pigeon 1.51 fix download 

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