X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=3d2bb4222953bfe78c29f495f20481b219db312f;hp=0a2519b62505087381d1396b6da30234c41edf6b;hb=ad2ad4c65706c18a5383506d361f1f23fc6a26ab;hpb=875183b310a8249922c2155e82cb4cecfae2097e

diff --git a/src/search.cpp b/src/search.cpp
index 0a2519b6..3d2bb422 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1131,7 +1131,8 @@ moves_loop: // When in check, search starts from here
           extension = 1;
 
       // Castling extension
-      if (type_of(move) == CASTLING)
+      if (   type_of(move) == CASTLING
+          && popcount(pos.pieces(us) & ~pos.pieces(PAWN) & (to_sq(move) & KingSide ? KingSide : QueenSide)) <= 3)
           extension = 1;
 
       // Late irreversible move extension