Progress On Bricabrac

[Mike Sherwin]

Another little bug has invaded Bricabrac's house. I called the local pest exterminator but they said that was not the kind of bug they deal with. So progress will resume when I track down that bug. The only thing that Bric needs to be considered a minimal engine is three fold repetition detection. Too many half points are being lost right now. Yesterday hash values were added so it will be easy to add a 3frd table. Here is an interesting RR that just finished. TC 5 sec + 0.5 sec inc. Sherwin50.pgn.
Bricabrac - RomiChess64P3n : 6.0/100 1-89-10 (0000=000000000=000=00000=00==0000000000=00000000000000000000000000000000000000000000=000=00000001=00) 6% -478
Bricabrac - Tscp181 : 65.0/100 50-20-30 (111101001=0==1011111==0111==0111=11==11=11=01==0011=111011==0=11=1=01111=1010=111001==1=1==00==01=11) 65% +108
Tscp181 - RomiChess64P3n : 0.0/100 0-100-0 (0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000) 0% -1200

Just as this tournament was finishing Thomas provided me a link to MinimalChessEngine Chili. So I also downloaded Rustic-alpha-2_64-bit-popcnt. And added both engines to the tournament. So 700 games to go. I'll post those results when they are done.

[Mike Sherwin]

Well, there is a new bug and it is killing me. MinimalChessEngine seems to trigger the bug far more than the other engines. So many won games are being thrown away. However, I will let the test finish. I'll have to adjust the sores to reflect the true strength of Bricabrac. That will take some time. There are 714 of 1000 games completed. The unadjusted results so far are
vs MinimalChessEngine -92
vs Rustic -14

It is way past my bedtime so more will have to wait until tomorrow, I mean later today! gn

[Mike Sherwin]

Too much caffeine, couldn't sleep.

It appears that I may have found the bug. If indeed I have then I'll run a gauntlet against the same engines. Then that will be it until I get a new eval written. PESTO was fine while debugging but it simply has to go because it is not mine!
871/1000 complete.

[Mike Sherwin]

RomiChess64P3n - Bricabrac : 94.0/100 89-1-10 (1111=111111111=111=11111=11==1111111111=11111111111111111111111111111111111111111111=111=11111110=11) 94% +478
RomiChess64P3n - MinimalChessEngine : 91.5/100 87-4-9 (11111111=111=1101=11=111=1111111=111110111111111110111111111111111111111111111101=11111111=1111111=1) 92% +424
RomiChess64P3n - Rustic-alpha-2_64-bit-popcnt : 98.5/100 98-1-1 (111111111111111111111=111111111111111111111111011111111111111111111111111111111111111111111111111111) 99% +798
RomiChess64P3n - Tscp181 : 100.0/100 100-0-0 (1111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111) 100% +1200


MinimalChessEngine - Bricabrac : 61.0/100 38-16-46 (11=1=1=1=1=1111==11===1111=0=1=0=1=1=110110===0==00=0==1==100=10==1======1100=11111===110===1=010===) 61% +78
MinimalChessEngine - RomiChess64P3n : 8.5/100 4-87-9 (00000000=000=0010=00=000=0000000=000001000000000001000000000000000000000000000010=00000000=0000000=0) 9% -402
MinimalChessEngine - Rustic-alpha-2_64-bit-popcnt : 61.0/100 51-29-20 (11==0110==01=0=01011==00101110=00==10111==0111110111100=01001110000110=10==11110111111=1111=011101=1) 61% +78
MinimalChessEngine - Tscp181 : 68.5/100 58-21-21 (10110=1=011=1=1101=011==1=111==1=01=111=111=011=1111=10011100110=111=1111=0101111111011110=10=001100) 69% +139


Rustic-alpha-2_64-bit-popcnt - Bricabrac : 54.0/100 33-25-42 (=1=100=1==01=1====01=1=1=110=1=00=1101============0=00=010=10111101==1=1=10101001101==00==110=01==01) 54% +28
Rustic-alpha-2_64-bit-popcnt - MinimalChessEngine : 39.0/100 29-51-20 (00==1001==10=1=10100==11010001=11==01000==1000001000011=10110001111001=01==00001000000=0000=100010=0) 39% -78
Rustic-alpha-2_64-bit-popcnt - RomiChess64P3n : 1.5/100 1-98-1 (000000000000000000000=000000000000000000000000100000000000000000000000000000000000000000000000000000) 2% -676
Rustic-alpha-2_64-bit-popcnt - Tscp181 : 55.0/100 48-38-14 (11100101101000100=0001011111000000=11111000110011011101111=1=11===1===1=11001001011011=0001100=0=111) 55% +35


Bricabrac - MinimalChessEngine : 39.0/100 16-38-46 (00=0=0=0=0=0000==00===0000=1=0=1=0=0=001001===1==11=1==0==011=01==0======0011=00000===001===0=101===) 39% -78
Bricabrac - RomiChess64P3n : 6.0/100 1-89-10 (0000=000000000=000=00000=00==0000000000=00000000000000000000000000000000000000000000=000=00000001=00) 6% -478
Bricabrac - Rustic-alpha-2_64-bit-popcnt : 46.0/100 25-33-42 (=0=011=0==10=0====10=0=0=001=0=11=0010============1=11=101=01000010==0=0=01010110010==11==001=10==10) 46% -28
Bricabrac - Tscp181 : 65.0/100 50-20-30 (111101001=0==1011111==0111==0111=11==11=11=01==0011=111011==0=11=1=01111=1010=111001==1=1==00==01=11) 65% +108

[lithander]

That are some pretty high draw rates, aren't they? Do you still know if the draws are caused by three-fold-repetitions? I guess your engine isn't alone in not handling that properly. I really need to handle that better because while MMC won't repeat a position if it thinks it's winning it isn't actively preventing the opponent from repeating positions.

[Mike Sherwin]

That are some pretty high draw rates, aren't they? Do you still know if the draws are caused by three-fold-repetitions? I guess your engine isn't alone in not handling that properly. I really need to handle that better because while MMC won't repeat a position if it thinks it's winning it isn't actively preventing the opponent from repeating positions.

Of the 46 draws 6 were clear wins for Bricabrac. Games like this one.
[pgn][Event "TSCP.at"]
[Site "DESKTOP-HFVHK2B"]
[Date "2021.04.26"]
[Round "31"]
[White "Bricabrac"]
[Black "MinimalChessEngine"]
[Result "1/2-1/2"]
[BlackElo "2200"]
[ECO "C45"]
[Opening "Scotch"]
[Time "22:40:30"]
[Variation "Steinitz, 5.Nc3"]
[WhiteElo "2200"]
[TimeControl "5+0"]
[Termination "normal"]
[PlyCount "67"]
[WhiteType "human"]
[BlackType "human"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Qh4 {(Qd8-h4 Nb1-c3 Bf8-b4 Qd1-d3
Ng8-f6 Nd4-b5) -0.13/6} 5. Nc3 {(b1c3 f8b4 d1d3 b4c3 b2c3 c6e5 d3e2 g8f6
d4f5) +0.14/9} Bb4 {(Bf8-b4 Bc1-e3 Qh4xe4 Nd4-b5 Bb4xc3+ b2xc3) -0.08/6} 6.
Qd3 {(d1d3 b4c3 b2c3 c6e5 d3e2 g8f6 d4f5 h4e4 f5g7) +0.14/9} Nf6 {(Ng8-f6
Nd4xc6 d7xc6 e4-e5 Nf6-g4 g2-g3) 0.00/6} 7. Nxc6 {(d4c6 d7c6 e4e5 f6g4 g2g3
h4h5 f2f4 b4c3 d3c3) 0.00/9} dxc6 {(d7xc6 e4-e5 Nf6-g4 Qd3-e2 O-O Bc1-f4)
+0.10/6} 8. e5 {(e4e5 f6g4 d3e2 h8f8 c1f4 c8e6 a1d1 b4c3 b2c3) -0.26/9} Ng4
{(Nf6-g4 Qd3-e2 Qh4-e7 Bc1-f4 Qe7-c5 Ra1-d1) +0.31/6 1} 9. Qe2 {(d3e2 b4c5
c3e4 c5d4 g2g3 h4d8 f2f4 h8f8 f1g2) -0.38/9} Bc5 {(Bb4-c5 Nc3-e4 Ng4xe5
Ne4xc5 Qh4-b4+ Bc1-d2) +0.66/6} 10. Ne4 {(c3e4 c5d4 g2g3 h4d8 f2f4 c8f5
c2c3 f5e4 e2e4) -0.46/9} Bd4 {(Bc5-d4 c2-c3 Bd4xe5 Bc1-g5 Qh4-h5 O-O-O)
+0.27/6} 11. h3 {(h2h3 g4e5 c2c3 d4b6 e4g5 f7f6 g2g3 h4h6 g5e6) -0.22/9}
Nxe5 {(Ng4xe5 Bc1-g5 Bd4xf2+ Ke1-d2 Ne5-c4+ Qe2xc4) -0.41/6} 12. Bg5 {(c1g5
d4f2 e1d2 c8g4 g5h4 g4e2 h4f2 e2f3 g2f3) +0.98/9} Bxf2+ {(Bd4xf2+ Ke1-d2
Bc8-g4 Bg5xh4 Bg4xe2 Bh4xf2) -1.02/6} 13. Kd2 {(e1d2 c8g4 g5h4 g4e2 h4f2
e2f1 h1f1 f7f5 f2d4 a8d8) +0.89/10} Bg4 {(Bc8-g4 Bg5xh4 Bg4xe2 Bh4xf2
Be2-b5 Kd2-c1) -1.32/6} 14. Bxh4 {(g5h4 g4e2 e4f2 e2f1 h1f1 e5c4 d2c1 c4e3
f1e1) +1.04/9} Bxe2 {(Bg4xe2 Bh4xf2 Be2xf1 Rh1xf1 O-O Ra1-d1 Rf8-e8)
-1.29/7} 15. Bxf2 {(h4f2 e2b5 d2c1 a8d8 f1b5 c6b5 f2g3 e5g6 g3c7) +1.51/9}
Bxf1 {(Be2xf1 Rh1xf1 O-O-O+ Kd2-c3 a7-a5 Ra1-d1 Rh8-e8) -1.29/7 1} 16.
Rhxf1 {(h1f1 a8d8 d2c1 h7h6 f2g3 d8d5 e4c3 d5c5 f1f5) +1.70/9} O-O {(O-O
Bf2-d4 Ra8-e8 Rf1-f5 Ne5-c4+ Kd2-d3 g7-g6) -1.51/7 1} 17. Rae1 {(a1e1 e5g6
f2c5 f8e8 d2c1 b7b6 c5d4 a8d8 c2c3) +1.44/9} Rfd8+ {(Rf8-d8+ Kd2-c3 b7-b5
Bf2-c5 a7-a5 Rf1-f5 b5-b4+) -1.54/7 1} 18. Kc1 {(d2c1 e5g6 f2g3 a8c8 c1b1
h7h6 c2c3 a7a6 f1f5 d8d3) +1.62/10} Nc4 {(Ne5-c4 b2-b3 Nc4-d6 Ne4xd6 c7xd6
Bf2-d4) -1.51/6} 19. b3 {(b2b3 c4b6 c2c4 a8c8 e4c5 d8e8 c5b7 e8e1 f1e1)
+2.21/9} Nd6 {(Nc4-d6 Ne4xd6 c7xd6 Re1-e7 b7-b6 Bf2-e3 f7-f6) -1.72/7} 20.
Nxd6 {(e4d6 d8d6 e1e7 d6g6 g2g4 g6h6 f2c5 b7b6 c5a3 f7f6) +2.38/10} cxd6
{(c7xd6 Re1-e7 b7-b6 Bf2-g3 f7-f6 Re7-e6 Kg8-f7) -2.12/7} 21. Re7 {(e1e7
b7b6 f2g3 f7f6 e7e6 g8f7 f1e1 a8c8 g3d6) +2.19/9} b6 {(b7-b6 Bf2-g3 f7-f6
Re7-e6 Kg8-f7 Rf1-e1 Rd8-e8) -2.24/7} 22. Bg3 {(f2g3 f7f6 e7b7 d8b8 b7b8
a8b8 g3d6 b8c8 c1d2 g8f7) +2.41/10} f6 {(f7-f6 Rf1-e1 a7-a5 Re7-b7 Ra8-b8
Rb7xb8 Rd8xb8) -2.31/7} 23. Rb7 {(e7b7 d8b8 b7d7 b8d8 d7d6 d8d6 g3d6 a8d8
f1d1) +2.50/9} Rdb8 {(Rd8-b8 Rb7-e7 Rb8-e8 Re7-c7 d6-d5 Rc7xc6 Re8-e2)
-2.21/7 1} 24. Rc7 {(b7c7 b8c8 c7b7 c8b8 b7b8 a8b8 g3d6 b8c8 c1d2 g8f7)
+2.41/10} Rc8 {(Rb8-c8 Rc7-b7 Rc8-e8 Bg3xd6 Re8-e2 Rb7-c7 Re2xg2) -2.25/7}
25. Bxd6 {(g3d6 c8c7 d6c7 a8c8 c7f4 g8f7 c1d2 f7e6 f1g1 h7h5) +2.44/10}
Rxc7 {(Rc8xc7 Bd6xc7 Ra8-c8 Bc7-f4 Kg8-f7 Kc1-d2 Kf7-e6 Kd2-e3) -2.25/8}
26. Bxc7 {(d6c7 a8c8 c7f4 g8f7 c1d2 h7h5 h3h4 c8d8 d2c3 f7e6) +2.45/10} Rc8
{(Ra8-c8 Bc7-f4 Kg8-f7 Kc1-d2 h7-h5 Kd2-e3 h5-h4) -2.16/7} 27. Bf4 {(c7f4
g8f7 c1d2 f7e6 d2c3 g7g5 f4e3 h7h5 e3d4 f6f5) +2.45/10} Rd8 {(Rc8-d8 Rf1-d1
Rd8xd1+ Kc1xd1 Kg8-f7 Kd1-e2 Kf7-e6) -2.18/7} 28. Kb2 {(c1b2 g8f7 b2c3 h7h5
h3h4 f7e6 f1g1 d8d5 c3c4 d5c5) +2.56/10} Kf7 {(Kg8-f7 Kb2-c3 h7-h5 h3-h4
Kf7-e6 Rf1-c1 c6-c5) -2.23/7} 29. Kc3 {(b2c3 f7e6 f4e3 h7h5 h3h4 d8g8 f1e1
e6d5 e1g1) +2.59/9} h5 {(h7-h5 h3-h4 c6-c5 Rf1-e1 Rd8-d4 g2-g3 Kf7-g6)
-2.24/7} 30. Be3 {(f4e3 d8e8 c3d3 e8d8 d3c4 h5h4 f1f4 b6b5 c4c5 g7g5)
+2.52/10} Re8 {(Rd8-e8 Kc3-d3 Re8-d8+ Kd3-e4 h5-h4 Rf1-f4 Rd8-e8+) -2.22/7}
31. Kd3 {(c3d3 e8d8 d3c4 d8e8 f1f3 f7e6 e3d4 e8g8 f3e3 e6f5) +2.51/10} Rd8+
{(Re8-d8+ Kd3-c3 Rd8-e8 Rf1-e1 h5-h4 Kc3-d3 c6-c5) -2.21/7} 32. Kc3 {(d3c3
d8e8 c3d3 e8d8 d3c4 h5h4 f1f4 b6b5 c4c5 g7g5) +2.52/10} Re8 {(c6-c5 h3-h4
Rd8-e8 Kc3-d3 Re8-d8+ Kd3-e4 Kf7-e6) -2.27/7} 33. Kd3 {(c3d3 e8d8 d3c4 d8e8
f1f3 f7e6 e3d4 e8g8 f3e3 e6f5) +2.51/10} Rd8+ {(c6-c5 h3-h4 Kf7-e6 a2-a4
Re8-d8+ Kd3-e4 a7-a5) -2.27/7} 34. Kc3 {(d3c3 d8e8 c3d3 e8d8 d3c4 h5h4 f1f4
b6b5 c4c5 g7g5) +2.52/10 3-fold repetition} 1/2-1/2
[/pgn]

And in ten Bricabrac had a substantial advantage. Like this one.
[pgn][Event "TSCP.at"]
[Site "DESKTOP-HFVHK2B"]
[Date "2021.04.27"]
[Round "46"]
[White "MinimalChessEngine"]
[Black "Bricabrac"]
[Result "1/2-1/2"]
[BlackElo "2000"]
[ECO "C92"]
[Opening "Spanish"]
[Time "01:18:05"]
[Variation "Closed, Zaitsev, 10.d4"]
[WhiteElo "2200"]
[TimeControl "5+0"]
[Termination "normal"]
[PlyCount "58"]
[WhiteType "human"]
[BlackType "program"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Be7 6. Re1 d6 7. c3 b5 8.
Bb3 O-O 9. h3 Bb7 {(c8b7 d2d4 a8c8 b1d2 e5d4 c3d4 h7h6 d4d5 c6e5) +0.05/9}
10. d4 {(d2-d4 e5xd4 c3xd4 d6-d5 e4xd5 Nf6xd5) -0.02/6} Rc8 {(a8c8 f3g5
h7h6 b3f7 f8f7 g5f7 g8f7 a2a3) +0.07/8} 11. Nbd2 {(Nb1-d2 e5xd4 c3xd4
Rf8-e8 d4-d5 Nc6-e5) -0.02/6} b4 {(b5b4 a1b1 h7h6 d2c4 e5d4 c3d4 d6d5 e4d5
f6d5) +0.11/9} 12. d5 {(d4-d5 b4xc3 b2xc3 Nc6-a5 Bc1-b2 Na5xb3) +0.35/6}
bxc3 {(b4c3 d2c4 c3b2 c1b2 c6a7 c4a5 b7a8 a2a4 c7c6) -0.07/9} 13. bxc3
{(b2xc3 Nc6-a5 Bc1-b2 Na5xb3 a2xb3 c7-c6 c3-c4) +0.20/7 1} Na5 {(c6a5 b3c2
c7c6 c3c4 d8c7 c2d3 c6d5 c4d5 c8d8) +0.09/9} 14. Bb2 {(Bc1-b2 Na5xb3 a2xb3
Rf8-e8 Nd2-c4 c7-c6 d5xc6) +0.15/7 1} Nxb3 {(a5b3 d1b3 c8b8 b3c2 c7c6 c3c4
c6d5 c4d5 b8c8) +0.30/9} 15. axb3 {(a2xb3 c7-c6 d5xc6 Rc8xc6 Qd1-c2 Rc6-c8
Ra1-d1) +0.25/7} c6 {(c7c6 d5c6 c8c6 d2c4 c6c8 d1c2 b7e4 e1e4 f6e4)
-0.01/9} 16. dxc6 {(d5xc6 Rc8xc6 Nd2-c4 Rc6-c8 Qd1-c2 Rf8-e8 Ra1-d1)
+0.29/7 1} Rxc6 {(c8c6 d2f1 c6c5 f1g3 d6d5 b3b4 c5b5 f3e5 f6e4) -0.11/9}
17. Qc2 {(Qd1-c2 Qd8-a8 Ra1-d1 Rc6-c8 b3-b4 Rf8-e8) +0.25/6} Rc8 {(c6c8
a1d1 h7h6 d2c4 d8c7 c2d3 c8d8 d3c2 f8e8) +0.05/9} 18. Nc4 {(Nd2-c4 h7-h6
Ra1-b1 Qd8-c7 Rb1-d1 Rf8-e8) +0.18/6} Bxe4 {(b7e4 c2e2 e4b7 a1d1 b7d5 c4d2
a6a5 c3c4 d5c6) +1.08/9} 19. Rxe4 {(Re1xe4 Nf6xe4 Qc2xe4 d6-d5 Qe4xe5
d5xc4) -0.69/6} Nxe4 {(f6e4 c2e4 d6d5 e4e5 d5c4 b3c4 c8c4 e5e2 c4f4)
+1.30/9} 20. Qxe4 {(Qc2xe4 d6-d5 Qe4xe5 Be7-f6 Qe5-f4 d5xc4) -0.87/6} d5
{(d6d5 e4e2 d5c4 b3c4 e7f6 f3e5 d8e7 f2f4 c8e8) +0.98/9} 21. Qe2 {(Qe4-e2
e5-e4 Nc4-e3 e4xf3 Qe2xf3 Rc8-b8) -0.88/6} dxc4 {(d5c4 b3c4 e7d6 a1a6 d8c7
f3g5 d6e7 g5f3 e7f6) +1.39/9} 22. bxc4 {(b3xc4 Qd8-c7 Nf3xe5 Be7-d6 f2-f4
Bd6xe5) -1.12/6} Re8 {(f8e8 a1a6 e7f6 a6a7 c8c7 a7a5 c7c4 a5e5 f6e5)
+1.43/9} 23. Rxa6 {(Ra1xa6 Be7-c5 Nf3-d2 Rc8-a8 Ra6-c6 Ra8-a2) -1.19/6} Qc7
{(d8c7 a6a1 e7f6 f3d2 g7g6 d2e4 f6g7 c4c5 c8d8) +1.57/9} 24. Ra1 {(Ra6-a1
Be7-f6 Nf3-d2 h7-h6 Ra1-d1 Rc8-d8) -1.42/6} Bf6 {(e7f6 f3d2 h7h6 d2e4 f6e7
e2h5 e7f8 a1d1 c7c4) +1.61/9} 25. Nd2 {(Nf3-d2 h7-h6 Ra1-e1 Bf6-g5 Nd2-f3
Bg5-f6 Nf3-d2) -1.36/7 1} Bg5 {(f6g5 d2e4 g5e7 e4d2 e7g5 a1e1 g5f4 g2g3
f4d2) +1.56/9} 26. Ne4 {(Nd2-e4 Bg5-e7 Ra1-a4 h7-h6 Qe2-f3 Qc7-b6 Qf3-e2)
-1.22/7 1} Be7 {(g5e7 a1a4 h7h6 e4g3 g7g6 g3e4 f7f5 e4g3 e7f6) +1.58/9} 27.
Nd2 {(Ne4-d2 Be7-g5 Nd2-e4 Bg5-f4 c4-c5 h7-h6) -1.31/6} Bg5 {(e7g5 d2e4
g5e7 e4d2 e7g5 a1e1 g5f4 g2g3 f4d2) +1.56/9} 28. Ne4 {(Ra1-e1 Bg5-f4 Bb2-c1
Bf4xd2 Bc1xd2 Qc7xc4) -1.74/6} Be7 {(g5e7 a1a4 h7h6 e4g3 g7g6 g3e4 f7f5
e4g3 e7f6) +1.58/9} 29. Nd2 {(Ra1-a4 Re8-d8 Kg1-h2 f7-f5 Ne4-g3 f5-f4)
-1.33/6} Bg5 {(e7g5 d2e4 g5e7 e4d2 e7g5 a1e1 g5f4 g2g3 f4d2) +1.56/9 3-fold
repetition} 1/2-1/2
[/pgn]

So if 11 half points are adjusted the score would be 38-27-35 +38.

I did not see any draws where MCE allowed a 3FR when it should not have.

[Mike Sherwin]

I have discovered that the "impossible to find bug" does not happen in debug mode.
It only happens in release mode.
It happens even if all optimizations are disabled.

All this time I thought I had become too stupid to logically think correctly.
But, it is not me.
It's MicroSoft!

Now I don't know what I am going to do

If anyone wants to help it happens at depth one in this position.
[d]7K/8/7p/1k5P/4P1P1/2P5/B7/8 w - - 16 64
FEN: 7K/8/7p/1k5P/4P1P1/2P5/8/1B6 w - - 0 65

Bricabrac:
1 00:00 16 16 +M0 a2b1
2 00:00 146 146 +M0 a2b1
3 00:00 1k 1k +M0 a2b1
4 00:00 11k 11k +M0 a2b1
5 00:00 36k 36k +M0 a2b1
6 00:00 37k 37k +M0 a2b1
7 00:00 38k 38k +M0 a2b1
8 00:00 44k 44k +M0 a2b1
9 00:00 58k 58k +M0 a2b1
10 00:00 97k 97k +M0 a2b1
11 00:00 187k 187k +M0 a2b1
12 00:00 435k 43,496k +M0 a2b1
13 00:00 998k 24,939k +M0 a2b1

It first shows up in this position.
[d]8/8/P2k3p/7P/4PKP1/1BP5/8/8 b - - 0 53
FEN: 8/8/P2k3p/7P/4PKP1/1BP5/8/8 b - - 0 53

Bricabrac:
1 00:00 8 8 -8.24 d6c5
2 00:00 59 59 -9.08 d6c5 a6a7
3 00:00 351 351 -9.40 d6c6 a6a7 c6b7
4 00:00 1k 1k -8.88 d6c6 f4e5 c6b6 b3c4
5 00:00 3k 3k -8.64 d6c6 f4e5 c6b6 b3c4 b6c5
6 00:00 8k 8k -9.00 d6c6 f4e5 c6c7 e5e6 c7b6 b3c4
7 00:00 14k 14k -9.00 d6c6 f4e5 c6b6 b3c4 b6a7 e5e6 a7b6
8 00:00 53k 53k -9.35 d6c6 b3c4 c6b6 f4f5 b6a7 f5g6 a7b6 g6h6
9 00:00 77k 77k -14.64 d6c6 a6a7 c6b7 e4e5 b7a7 e5e6 a7b6 e6e7 b6c5
10 00:00 711k 23,688k -M0 d6c6 a6a7 c6b7 e4e5 b7a7 e5e6 a7b6 e6e7 b6c5

[Mike Sherwin]

Maybe this is a clue in debug mode.
r n b q k b n r
p p p p p p p p
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
P P P P P P P P
R N B Q K B N R

Enter Command(w):
setboard 8/8/P2k3p/7P/4PKP1/1BP5/8/8 b - - 0 53
. . . . . . . .
. . . . . . . .
P . . k . . . p
. . . . . . . P
. . . . P K P .
. B P . . . . .
. . . . . . . .
. . . . . . . .

Enter Command(b):
st 30
. . . . . . . .
. . . . . . . .
P . . k . . . p
. . . . . . . P
. . . . P K P .
. B P . . . . .
. . . . . . . .
. . . . . . . .

Enter Command(b):
go

Begin Depth 1
1 -824 0 8 d6c5

Begin Depth 2
2 -908 0 59 d6c5 a6a7

Begin Depth 3
3 -940 0 351 d6c6 a6a7 c6b7

Begin Depth 4
4 -888 0 1474 d6c6 f4e5 c6b6 b3c4

Begin Depth 5
5 -864 0 2934 d6c6 f4e5 c6b6 b3c4 b6c5

Begin Depth 6
6 -900 0 8011 d6c6 f4e5 c6c7 e5e6 c7b6 b3c4

Begin Depth 7
7 -900 0 13575 d6c6 f4e5 c6b6 b3c4 b6a7 e5e6 a7b6

Begin Depth 8
8 -935 1 54814 d6c6 b3c4 c6b6 f4f5 b6a7 f5g6 a7b6 g6h6

Begin Depth 9
9 -1464 2 78427 d6c6 a6a7 c6b7 e4e5 b7a7 e5e6 a7b6 e6e7 b6c5

Begin Depth 10
10 -1110 10 365908 d6c6 b3c4 c6b6 e4e5 b6c6 e5e6 c6c7 a6a7 c7b7 e6e7

Begin Depth 11
11 -1478 43 1450114 d6c6 e4e5 c6b6 b3f7 b6a6 e5e6 a6b6 e6e7 b6c6 f4e5 c6c5

Begin Depth 12
12 -1512 188 6571306 d6c6 e4e5 c6b6 e5e6 b6c6 a6a7 c6b7 e6e7 b7a7 e7e8q╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠♦ a7b6 f4e5

Begin Depth 13
13 -1536 642 21469963 d6c6 e4e5 c6b6 e5e6 b6c6 f4e5 c6c7 b3d5 c7b6 e6e7 b6a6 e5e6 a6b6

Begin Depth 14
14 -1555 2610 91415295 d6c6 e4e5 c6b6 e5e6 b6c6 f4e5 c6c7 b3d5 c7b6 e6e7 b6a6 e7e8q╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠♦ a6b6 e8e7

Begin Depth 15

Move Played: D6C6 Score: -1555
. . . . . . . .
. . . . . . . .
P . k . . . . p
. . . . . . . P
. . . . P K P .
. B P . . . . .
. . . . . . . .
. . . . . . . .

Enter Command(w):

[Sven]

Just a stupid thought ... The debug version might differ from the release version through #ifdef or assert(...) or something like that ...

[Sven]

Begin Depth 12
12 -1512 188 6571306 d6c6 e4e5 c6b6 e5e6 b6c6 a6a7 c6b7 e6e7 b7a7 e7e8q╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠♦ a7b6 f4e5

Begin Depth 13
13 -1536 642 21469963 d6c6 e4e5 c6b6 e5e6 b6c6 f4e5 c6c7 b3d5 c7b6 e6e7 b6a6 e5e6 a6b6

Begin Depth 14
14 -1555 2610 91415295 d6c6 e4e5 c6b6 e5e6 b6c6 f4e5 c6c7 b3d5 c7b6 e6e7 b6a6 e7e8q╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠♦ a6b6 e8e7

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