From: Marco Costalba <mcostalba@gmail.com>
Date: Thu, 7 Oct 2010 02:55:08 +0000 (+0100)
Subject: Properly set to zero stuff returned by 'new'
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=9ca4359f3691305fc5e3306c3084c83557ce09c0;p=fairystockfish.git

Properly set to zero stuff returned by 'new'

Language guarantees that c'tor is called, but without any c'tor
it happens to work by accident because OS zeroes out the freshly
allocated pages. The problem is that if I deallocate and allocate
again, the second time pages are no more newly come by the OS and
so could contain stale info.

A practical case could be if we change TT size or numbers of
threads on the fly while already running.

Bug spotted by Justin Blanchard.

No functional change.

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

diff --git a/src/material.cpp b/src/material.cpp
index 71e057a..5e8f75d 100644
--- a/src/material.cpp
+++ b/src/material.cpp
@@ -146,6 +146,7 @@ MaterialInfoTable::MaterialInfoTable() {
            << " bytes for material hash table." << endl;
       Application::exit_with_failure();
   }
+  memset(entries, 0, MaterialTableSize * sizeof(MaterialInfo));
 }
 
 MaterialInfoTable::~MaterialInfoTable() {
diff --git a/src/pawns.cpp b/src/pawns.cpp
index 07decab..9a0059d 100644
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -90,6 +90,7 @@ PawnInfoTable::PawnInfoTable() {
                 << " bytes for pawn hash table." << std::endl;
       Application::exit_with_failure();
   }
+  memset(entries, 0, PawnTableSize * sizeof(PawnInfo));
 }
 
 
diff --git a/src/tt.cpp b/src/tt.cpp
index b730dbe..375c00a 100644
--- a/src/tt.cpp
+++ b/src/tt.cpp
@@ -72,6 +72,7 @@ void TranspositionTable::set_size(size_t mbSize) {
                     << " MB for transposition table." << std::endl;
           Application::exit_with_failure();
       }
+      clear();
   }
 }