Allow to prune also first move

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 52bc9f88eea5eb031931cfe1aa17dce81fde575e..3aede5adfa7f111b42ddef9332e9182a5dfba8f5 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -182,7 +182,7 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns,
       // pawn on neighboring files is higher or equal than the number of
       // enemy pawns in the forward direction on the neighboring files.
       candidate =   !(opposed | passed | backward | isolated)
-                 && (b = attack_span_mask(Them, s + pawn_push(Us)) & ourPawns) != EmptyBoardBB
+                 && (b = attack_span_mask(Them, s + pawn_push(Us)) & ourPawns) != 0
                  &&  count_1s<Max15>(b) >= count_1s<Max15>(attack_span_mask(Us, s) & theirPawns);
 
       // Passed pawns will be properly scored in evaluation because we need
@@ -223,7 +223,7 @@ Score PawnInfo::updateShelter(const Position& pos, Square ksq) {
 
   if (relative_rank(Us, ksq) <= RANK_4)
   {
-      pawns = pos.pieces(PAWN, Us) & this_and_neighboring_files_bb(ksq);
+      pawns = pos.pieces(PAWN, Us) & this_and_neighboring_files_bb(file_of(ksq));
       r = ksq & (7 << 3);
       for (int i = 0; i < 3; i++)
       {