X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fbook.cpp;h=7cb0863c11158b2f414a0c2868d0a8041b5b3cf9;hb=358ccf206ba142a68c7b5b3622a79cc309107f6d;hp=0212317f88ce281608af946e1bad631a58c0122b;hpb=9dcc2aad98b970380a66b61f2238875e9051de97;p=stockfish

diff --git a/src/book.cpp b/src/book.cpp
index 0212317f..7cb0863c 100644
--- a/src/book.cpp
+++ b/src/book.cpp
@@ -528,7 +528,7 @@ namespace {
   uint64_t book_key(const Position& pos) {
 
     uint64_t result = 0;
-    Bitboard b = pos.pieces_of_color(WHITE) | pos.pieces_of_color(BLACK);
+    Bitboard b = pos.occupied_squares();
 
     while (b)
     {