From: Joona Kiiski <joona.kiiski@gmail.com>
Date: Sat, 28 Nov 2009 18:49:36 +0000 (+0200)
Subject: Do not crash if we are asked to search mate or stalemate position.
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=ae0b96571134e640ccebcd4a79983340b9494a7a;hp=455993b289b3c8f1c9c73af5876eb0190cde537c

Do not crash if we are asked to search mate or stalemate position.

We might be asked to ponder mate or stalemate position.
This being the case, simply wait for stop or ponderhit.
Currently we crash.

UCI specs aren't clear on the issue, but it cost nothing to
add little check.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
---

diff --git a/src/search.cpp b/src/search.cpp
index b8669328..4b93a210 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -677,6 +677,14 @@ namespace {
     // searchMoves are verified, copied, scored and sorted
     RootMoveList rml(p, searchMoves);
 
+    if (rml.move_count() == 0)
+    {
+        if (PonderSearch)
+            wait_for_stop_or_ponderhit();
+
+        return pos.is_check()? -VALUE_MATE : VALUE_DRAW;
+    }
+
     // Print RootMoveList c'tor startup scoring to the standard output,
     // so that we print information also for iteration 1.
     std::cout << "info depth " << 1 << "\ninfo depth " << 1