StateInfo is usually allocated on the stack by search()

[stockfish] / src / uci.cpp

diff --git a/src/uci.cpp b/src/uci.cpp
index 4d12ca40c30dc43d11ea64c5b22fadc39503f9d9..cfd253b1f586a5c8d7ddda7f50bb8b5b8162eeac 100644 (file)
--- a/src/uci.cpp
+++ b/src/uci.cpp
@@ -39,10 +39,10 @@ namespace {
   // FEN string of the initial position, normal chess
   const char* StartFEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
 
-  // Stack to keep track of the position states along the setup moves (from the
+  // A list to keep track of the position states along the setup moves (from the
   // start position to the position just before the search starts). Needed by
   // 'draw by repetition' detection.
-  Search::StateStackPtr SetupStates;
+  StateListPtr States(new std::vector<StateInfo>(1));
 
 
   // position() is called when engine receives the "position" UCI command.
@@ -68,14 +68,14 @@ namespace {
     else
         return;
 
-    pos.set(fen, Options["UCI_Chess960"], Threads.main());
-    SetupStates = Search::StateStackPtr(new std::stack<StateInfo>);
+    States = StateListPtr(new std::vector<StateInfo>(1));
+    pos.set(fen, Options["UCI_Chess960"], &States->back(), Threads.main());
 
     // Parse move list (if any)
     while (is >> token && (m = UCI::to_move(pos, token)) != MOVE_NONE)
     {
-        SetupStates->push(StateInfo());
-        pos.do_move(m, SetupStates->top(), pos.gives_check(m, CheckInfo(pos)));
+        States->push_back(StateInfo());
+        pos.do_move(m, States->back(), pos.gives_check(m, CheckInfo(pos)));
     }
   }
 
@@ -132,7 +132,7 @@ namespace {
         else if (token == "infinite")  limits.infinite = 1;
         else if (token == "ponder")    limits.ponder = 1;
 
-    Threads.start_thinking(pos, limits, SetupStates);
+    Threads.start_thinking(pos, States, limits);
   }
 
 } // namespace
@@ -146,9 +146,11 @@ namespace {
 
 void UCI::loop(int argc, char* argv[]) {
 
-  Position pos(StartFEN, false, Threads.main()); // The root position
+  Position pos;
   string token, cmd;
 
+  pos.set(StartFEN, false, &States->back(), Threads.main());
+
   for (int i = 1; i < argc; ++i)
       cmd += std::string(argv[i]) + " ";