message: Update matrix.cpp
  Fix race condition in getDefaultAllocator and setDefaultAllocator interaction / not threadsafe currently
diff: @@ -222,16 +222,20 @@ public:
  };
  namespace
  {
  - MatAllocator* g_matAllocator = NULL;
  + MatAllocator* volatile g_matAllocator = NULL;
  }
  MatAllocator* Mat::getDefaultAllocator()
  {
  + if (g_matAllocator == NULL)
  + {
  + cv::AutoLock lock(cv::getInitializationMutex());
  if (g_matAllocator == NULL)
  {
  g_matAllocator = getStdAllocator();
  }
  + }
  return g_matAllocator;
  }
  void Mat::setDefaultAllocator(MatAllocator* allocator)
  