Cancel tasks on shutdown

src/base/thread_pool.cc

@@ -56,6 +56,10 @@ void ThreadPool::PostTaskAndReply(const Location& from,
   semaphore_.release();
 }
 
+void ThreadPool::CancelTasks() {
+  task_runner_.CancelTasks();
+}
+
 void ThreadPool::WorkerMain() {
   for (;;) {
     semaphore_.acquire();

src/base/thread_pool.h

@@ -39,6 +39,8 @@ class ThreadPool {
     semaphore_.release();
   }
 
+  void CancelTasks();
+
  private:
   std::vector<std::thread> threads_;
 

src/engine/engine.cc

@@ -50,6 +50,9 @@ Engine::Engine(Platform* platform)
 Engine::~Engine() {
   LOG << "Shutting down engine.";
 
+  thread_pool_.CancelTasks();
+  thread_pool_.Shutdown();
+
   game_.reset();
   stats_.reset();
   textures_.clear();

src/engine/renderer/vulkan/renderer_vulkan.cc

@@ -987,6 +987,7 @@ void RendererVulkan::Shutdown() {
     return;
 
   LOG << "Shutting down renderer.";
+  task_runner_.CancelTasks();
   quit_.store(true, std::memory_order_relaxed);
   semaphore_.release();
   setup_thread_.join();