From 466daf6fbafd1f58f064c2fa03d2fa2c1315c4f5 Mon Sep 17 00:00:00 2001
From: syzygy1 <3028851+syzygy1@users.noreply.github.com>
Date: Tue, 18 Jun 2019 23:27:34 +0200
Subject: [PATCH] Partial revert of "Assorted trivial cleanups 5/2019".

Since root_probe() and root_probe_wdl() do not reset all tbRank values if they fail,
it is necessary to do this in rank_root_move(). This fixes issue #2196.
Alternatively, the loop could be moved into both root_probe() and root_probe_wdl().

No functional change
---
 src/search.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/search.cpp b/src/search.cpp
index d9543899..047a0892 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1713,4 +1713,10 @@ void Tablebases::rank_root_moves(Position& pos, Search::RootMoves& rootMoves) {
         if (dtz_available || rootMoves[0].tbScore <= VALUE_DRAW)
             Cardinality = 0;
     }
+    else
+    {
+        // Clean up if root_probe() and root_probe_wdl() have failed
+        for (auto& m : rootMoves)
+            m.tbRank = 0;
+    }
 }
-- 
2.39.2