use std::atomic<> to protect variables being accessed by multiple threads

There are several places where multiple threads are accessing the same variables simultaneously without any kind of protection. I propose using std::atomic<> to make it safer. I did a special build of lldb, using the google tool 'thread sanitizer' which identified many cases of multiple threads accessing the same memory. std::atomic is low overhead and does not use any locks for simple types such as int/bool.

See http://reviews.llvm.org/D5302 for more details.

Change by Shawn Best.

llvm-svn: 217818

1 files changed, 1 insertions, 2 deletions

diff --git a/lldb/source/Plugins/Process/POSIX/ProcessPOSIX.cpp b/lldb/source/Plugins/Process/POSIX/ProcessPOSIX.cpp
index c930a1881cd..d0cc9cd0a2e 100644
--- a/lldb/source/Plugins/Process/POSIX/ProcessPOSIX.cpp
+++ b/lldb/source/Plugins/Process/POSIX/ProcessPOSIX.cpp
@@ -434,8 +434,7 @@ ProcessPOSIX::SendMessage(const ProcessMessage &message)
         // FIXME: I'm not sure we need to do this.
         if (message.GetTID() == GetID())
         {
-            m_exit_status = message.GetExitStatus();
-            SetExitStatus(m_exit_status, NULL);
+            SetExitStatus(message.GetExitStatus(), NULL);
         }
         else if (!IsAThreadRunning())
             SetPrivateState(eStateStopped);