Stockfish 17040802_joergoster - new version!
Stockfish, chess engine UCI
Leader rating list JCER = 3405
🔬 Author: joergoster
Fix zugzwang pruning issues
By adding pos.non_pawn_material(pos.side_to_move()) as a precondition in step 13, which is already in use in Futility Pruning (child node) and Null Move Pruning for similar reasons.
Pawn endgames, especially those with only 1 or 2 pawns, are simply heavily influenced by zugzwang situations.
Since we are using a bitbase for KPK endgames, I see no reason to accept buggy evals as shown in #760
Patch looks neutral at STC
LLR: 2.32 (-2.94,2.94) [-3.00,1.00]
Total: 79580 W: 10789 L: 10780 D: 58011
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 27071 W: 3502 L: 3390 D: 20179
⭐⭐⭐ Stockfish 17040802_joergoster - download