Increase null verification threshold to 12 plies

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index ab34673463c57286d7ec4047a46755d6fc24701e..1abe022aacefa580d699131310127c8a7910437f 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -679,7 +679,7 @@ namespace {
             if (nullValue >= VALUE_MATE_IN_MAX_PLY)
                 nullValue = beta;
 
-            if (depth < 6 * ONE_PLY)
+            if (depth < 12 * ONE_PLY)
                 return nullValue;
 
             // Do verification search at high depths