Simplify Castle Extension

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index c9526ec3c683e38a013089dfcd98bb661f3f2c0e..e113068c408561c402f47513e685bb1b874b25a4 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -187,6 +187,7 @@ void Search::clear() {
   Time.availableNodes = 0;
   TT.clear();
   Threads.clear();
+  Tablebases::init(Options["SyzygyPath"]); // Free up mapped files
 }
 
 
@@ -943,6 +944,10 @@ moves_loop: // When in check, search starts from here
                &&  pos.see_ge(move))
           extension = ONE_PLY;
 
+      else if (   pos.can_castle(us) // Extension for king moves that change castling rights
+               && type_of(movedPiece) == KING)
+          extension = ONE_PLY;
+
       // Calculate new depth for this move
       newDepth = depth - ONE_PLY + extension;