From c93f7f5ceaf255bc9314be022b7bebb55b1d0605 Mon Sep 17 00:00:00 2001 From: ShadowNinja Date: Sat, 28 Jan 2017 17:02:43 -0500 Subject: Fix synchronization issue at thread start If a newly spawned thread called getThreadId or getThreadHandle before the spawning thread finished saving the thread handle, then the handle/id would be used uninitialized. This would cause the threading tests to fail since isCurrentThread would return false, and if Minetest is built with C++11 support the std::thread object pointer would be dereferenced while ininitialized, causing a segmentation fault. This fixes the issue by using a mutex to force the spawned thread to wait for the spawning thread to finish initializing the thread object. An alternative way to handle this would be to also set the thread handle/id in the started thread but this wouldn't work for C++11 builds because there's no way to get the partially constructed object. --- src/threading/thread.h | 1 + 1 file changed, 1 insertion(+) (limited to 'src/threading/thread.h') diff --git a/src/threading/thread.h b/src/threading/thread.h index 14a0e13ab..4785d3e03 100644 --- a/src/threading/thread.h +++ b/src/threading/thread.h @@ -153,6 +153,7 @@ private: Atomic m_request_stop; Atomic m_running; Mutex m_mutex; + Mutex m_start_finished_mutex; #if USE_CPP11_THREADS std::thread *m_thread_obj; -- cgit v1.2.3