From 89eeb36835fe9987283cad1660bbacc6ff1e8fab Mon Sep 17 00:00:00 2001
From: Tomasz Sobczyk <tomasz.sobczyk1997@gmail.com>
Date: Fri, 25 Sep 2020 13:42:27 +0200
Subject: [PATCH] Initialize Tablebases::MaxCardinality to 0 to prevent
 uninitialized variable read in rank_root_moves

---
 src/search.h           | 5 -----
 src/syzygy/tbprobe.cpp | 2 +-
 src/syzygy/tbprobe.h   | 2 ++
 3 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/src/search.h b/src/search.h
index 9e453d9a..ab832ee2 100644
--- a/src/search.h
+++ b/src/search.h
@@ -112,11 +112,6 @@ void clear();
 
 } // namespace Search
 
-namespace Tablebases {
-
-extern int MaxCardinality;
-
-}
 namespace Learner {
 
   // A pair of reader and evaluation value. Returned by Learner::search(),Learner::qsearch().
diff --git a/src/syzygy/tbprobe.cpp b/src/syzygy/tbprobe.cpp
index 4d682f1a..f4b9447f 100644
--- a/src/syzygy/tbprobe.cpp
+++ b/src/syzygy/tbprobe.cpp
@@ -52,7 +52,7 @@
 
 using namespace Tablebases;
 
-int Tablebases::MaxCardinality;
+int Tablebases::MaxCardinality = 0;
 
 namespace {
 
diff --git a/src/syzygy/tbprobe.h b/src/syzygy/tbprobe.h
index 6af5d278..5f97c746 100644
--- a/src/syzygy/tbprobe.h
+++ b/src/syzygy/tbprobe.h
@@ -25,6 +25,8 @@
 
 namespace Tablebases {
 
+extern int MaxCardinality;
+
 enum WDLScore {
     WDLLoss        = -2, // Loss
     WDLBlessedLoss = -1, // Loss, but draw under 50-move rule