While testing on a simple MNIST example on the Julia binding, I noticed the following error while the program finish running.

libc++abi.dylib: terminating with uncaught exception of type std::__1::system_error: mutex lock failed: Invalid argument

signal (6): Abort trap: 6
__pthread_kill at /usr/lib/system/libsystem_kernel.dylib (unknown line)

Before trying to dig out what is happening here, is this kind of error look familiar to anyone? Here are some more information:

• It only happens under Mac OS X. I also see this error on the unittest in travis OS X node, but locally unittest will not trigger this error. I have never see this error under Linux.
• It occurs only when the program finished running.