Position::move_is_capture() does not handle MOVE_NONE

[stockfish] / src / position.cpp

diff --git a/src/position.cpp b/src/position.cpp
index 8390facc5b501a040333c820285bd28e15573a29..98e79df2a82d2d661c9af66aa8d8004466da1bab 100644 (file)
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -39,6 +39,8 @@
 //// Variables
 ////
 
+extern SearchStack EmptySearchStack;
+
 int Position::castleRightsMask[64];
 
 Key Position::zobrist[2][8][64];
@@ -50,6 +52,7 @@ Key Position::zobSideToMove;
 Value Position::MgPieceSquareTable[16][64];
 Value Position::EgPieceSquareTable[16][64];
 
+static bool RequestPending = false;
 
 ////
 //// Functions
@@ -243,7 +246,7 @@ const std::string Position::to_fen() const {
 
       fen += (rank > RANK_1 ? '/' : ' ');
   }
-  fen += (sideToMove == WHITE ? 'w' : 'b') + ' ';
+  fen += (sideToMove == WHITE ? "w " : "b ");
   if (castleRights != NO_CASTLES)
   {
     if (can_castle_kingside(WHITE))  fen += 'K';
@@ -270,11 +273,18 @@ void Position::print(Move m) const {
 
   static const std::string pieceLetters = " PNBRQK  PNBRQK .";
 
+  // Check for reentrancy, as example when called from inside
+  // MovePicker that is used also here in move_to_san()
+  if (RequestPending)
+      return;
+
+  RequestPending = true;
+
   std::cout << std::endl;
   if (m != MOVE_NONE)
   {
-      Position p(*this);
-      std::cout << "Move is: " << move_to_san(p, m) << std::endl;
+      std::string col = (color_of_piece_on(move_from(m)) == BLACK ? ".." : "");
+      std::cout << "Move is: " << col << move_to_san(*this, m) << std::endl;
   }
   for (Rank rank = RANK_8; rank >= RANK_1; rank--)
   {
@@ -291,9 +301,11 @@ void Position::print(Move m) const {
       }
       std::cout << '|' << std::endl;
   }
-  std::cout << "+---+---+---+---+---+---+---+---+" << std::endl;
-  std::cout << "Fen is: " << to_fen() << std::endl;
-  std::cout << key << std::endl;
+  std::cout << "+---+---+---+---+---+---+---+---+" << std::endl
+            << "Fen is: " << to_fen() << std::endl
+            << "Key is: " << key << std::endl;
+
+  RequestPending = false;
 }
 
 
@@ -663,10 +675,12 @@ bool Position::move_is_check(Move m, Bitboard dcCandidates) const {
 
 
 /// Position::move_is_capture() tests whether a move from the current
-/// position is a capture.
+/// position is a capture. Move must not be MOVE_NONE.
 
 bool Position::move_is_capture(Move m) const {
 
+  assert(m != MOVE_NONE);
+
   return (   !square_is_empty(move_to(m))
           && (color_of_piece_on(move_to(m)) == opposite_color(side_to_move()))
          )
@@ -1913,8 +1927,7 @@ bool Position::is_mate() {
 
   if (is_check())
   {
-      MovePicker mp = MovePicker(*this, false, MOVE_NONE, MOVE_NONE,
-                                 MOVE_NONE, MOVE_NONE, Depth(0));
+      MovePicker mp = MovePicker(*this, false, MOVE_NONE, EmptySearchStack, Depth(0));
       return mp.get_next_move() == MOVE_NONE;
   }
   return false;