do_null_move copies the whole StateInfo from the previous state, which leaves capturedPiece holding the piece captured by the last real move, so inside the null-move subtree captured_piece() reports a stale capture. The priorCapture consumers in search are all guarded by prevSq != SQ_NONE or (ss-1)->currentMove.is_ok(), which are false at the null-move child, but the stalemate verification gate in qsearch reads captured_piece() unguarded and can be spuriously triggered by the stale value.
Clear the field, since a null move captures nothing.
Passed non-regression STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 82784 W: 21172 L: 21011 D: 40601
Ptnml(0-2): 194, 8976, 22923, 9073, 226
https://tests.stockfishchess.org/tests/view/6a2b5b356b4aa63ddbf31518
Passed non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 118134 W: 30007 L: 29891 D: 58236
Ptnml(0-2): 66, 11856, 35108, 11970, 67
https://tests.stockfishchess.org/tests/view/6a2c4c9c0d5d4b19d0805301
closes https://github.com/official-stockfish/Stockfish/pull/6910
No functional change
The following have zero call sites repo-wide:
SearchManager:🆔 never read or written (also never initialized, nor was it ever used).
Search::Worker::elapsed_time(): never called. PV output uses tm.elapsed_time() (TimeManager) directly. (removed callers on 25361e5)
MovePicker::begin()/end(): unused private accessors. (removed callers on 8c2d21f)
closes https://github.com/official-stockfish/Stockfish/pull/6909
No functional change
After merging the HalfKA and Threats accumulators (7c7fe322) and the
subsequent removal of the double-incremental/fused update, a number of
NNUE helpers and fields became unreachable. Each was verified to have
zero callers/readers across the source tree:
- FusedUpdateData logic in FullThreats: the fused-update branch of
append_changed_indices and the FusedUpdateData parameter are unused;
the accumulator update no longer passes fused data.
- FullThreats::requires_refresh: never called. The live king-bucket
refresh check is HalfKAv2_hm::requires_refresh (PSQFeatureSet), used
in nnue_accumulator.
- HalfKAv2_hm::append_active_indices: never called. The live
active-index builder is FullThreats::append_active_indices
(ThreatFeatureSet).
- DirtyThreats::us, prevKsq and ksq: written in do_move but only read by
the now-removed FullThreats::requires_refresh. Removing them also
drops three stores from the do_move path.
- Unused feature Name constants and the unused FtOneVal / HiddenMaxVal
constants in nnue_common.h.
- Two stale feature-header banner comments.
closes https://github.com/official-stockfish/Stockfish/pull/6898
No functional change
The FEN validation check intended to reject pawns on the first or eighth rank uses the `Rank` enum values in a bitwise OR operation:
`if (pieces(PAWN) & (RANK_1 | RANK_8))`
`RANK_1 | RANK_8` evaluates to the integer `0 | 7 == 7` instead of a bitboard, so the expression only tests squares A1, B1 and C1. As a result, unsupported positions with pawns elsewhere on the first or eighth rank are silently accepted. For instance, `position fen 3P3k/8/8/8/8/8/8/3K4 w - - 0 1` is accepted even though the pawn on d8 makes the position unsupported.
Use the `Rank1BB | Rank8BB` bitboard constants so any pawn on the first or eighth rank are correctly rejected.
closes https://github.com/official-stockfish/Stockfish/pull/6887
No functional change
