diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 10dddc7d..23af60f3 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -641,7 +641,7 @@ namespace {
                 bb = forward_file_bb(Them, s) & pos.pieces(ROOK, QUEEN);
 
                 if (!(pos.pieces(Them) & bb))
-                    unsafeSquares &= attackedBy[Them][ALL_PIECES] | pos.pieces(Them);
+                    unsafeSquares &= attackedBy[Them][ALL_PIECES];
 
                 // If there are no enemy attacks on passed pawn span, assign a big bonus.
                 // Otherwise assign a smaller bonus if the path to queen is not attacked