From 2eb0203bf43e635b756bbf1322c53b8d299d4b37 Mon Sep 17 00:00:00 2001
From: John Firebaugh <john.firebaugh@gmail.com>
Date: Fri, 13 Nov 2015 14:00:13 -0800
Subject: [PATCH] [core] Cancelled flag needs to be atomic; it is read from
 multiple threads

---
 src/mbgl/util/run_loop.hpp | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/mbgl/util/run_loop.hpp b/src/mbgl/util/run_loop.hpp
index 5bf3551e5..6113ac221 100644
--- a/src/mbgl/util/run_loop.hpp
+++ b/src/mbgl/util/run_loop.hpp
@@ -10,6 +10,7 @@
 #include <utility>
 #include <queue>
 #include <mutex>
+#include <atomic>
 
 namespace mbgl {
 namespace util {
@@ -45,7 +46,7 @@ public:
     template <class Fn, class... Args>
     std::unique_ptr<WorkRequest>
     invokeCancellable(Fn&& fn, Args&&... args) {
-        auto flag = std::make_shared<bool>();
+        auto flag = std::make_shared<std::atomic<bool>>();
         *flag = false;
 
         auto tuple = std::make_tuple(std::move(args)...);
@@ -64,7 +65,7 @@ public:
     template <class Fn, class Cb, class... Args>
     std::unique_ptr<WorkRequest>
     invokeWithCallback(Fn&& fn, Cb&& callback, Args&&... args) {
-        auto flag = std::make_shared<bool>();
+        auto flag = std::make_shared<std::atomic<bool>>();
         *flag = false;
 
         // Create a lambda L1 that invokes another lambda L2 on the current RunLoop R, that calls
@@ -100,7 +101,7 @@ private:
     template <class F, class P>
     class Invoker : public WorkTask {
     public:
-        Invoker(F&& f, P&& p, std::shared_ptr<bool> canceled_ = nullptr)
+        Invoker(F&& f, P&& p, std::shared_ptr<std::atomic<bool>> canceled_ = nullptr)
           : canceled(canceled_),
             func(std::move(f)),
             params(std::move(p)) {
@@ -134,7 +135,7 @@ private:
         }
 
         std::recursive_mutex mutex;
-        std::shared_ptr<bool> canceled;
+        std::shared_ptr<std::atomic<bool>> canceled;
 
         F func;
         P params;