From 61bc8d12d39cb31303ec9162b1ca8a015d896192 Mon Sep 17 00:00:00 2001
From: Joost VandeVondele <Joost.VandeVondele@gmail.com>
Date: Fri, 18 Sep 2020 23:06:45 +0200
Subject: [PATCH] Fix some races in learning

declare a few variables atomic.

Other races remain...
---
 src/learn/learn.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/learn/learn.cpp b/src/learn/learn.cpp
index 6d0a777d..6142ce6b 100644
--- a/src/learn/learn.cpp
+++ b/src/learn/learn.cpp
@@ -695,14 +695,14 @@ namespace Learner
         uint64_t last_done;
 
         // If total_read exceeds this value, update_weights() and calculate mse.
-        uint64_t next_update_weights;
+        std::atomic<uint64_t> next_update_weights;
 
         uint64_t save_count;
 
         // Do not shuffle when reading the phase.
         bool no_shuffle;
 
-        bool stop_flag;
+        std::atomic<bool> stop_flag;
 
         vector<Key> hash;
 
@@ -785,7 +785,7 @@ namespace Learner
         // Mini batch size size. Be sure to set it on the side that uses this class.
         uint64_t mini_batch_size = LEARN_MINI_BATCH_SIZE;
 
-        bool stop_flag;
+        std::atomic<bool> stop_flag;
 
         // Discount rate
         double discount_rate;