This was submitted as a bug (https://svn.boost.org/trac/boost/ticket/12150), but I don't know that this is actually a boost bug, possibly a OSX or clang issue, or maybe I'm just doing something silly, so I'm hoping someone here can shed some light on the issue. I'm trying to use boost's shared memory system to get data from another application, but while it works fine on Ubuntu 15.10 with boost 1.58 and 1.60 on gcc, clang-3.6 and clang-3.7, it throws an exception when it attempts to acquire the mutex lock on OSX because the mutex has not been initialized. Placing a breakpoint in the constructor for the recursive_lock never gets hit, and I'm not sure why. Hopefully someone with more OSX experience can help me sort this out. Thanks very much for your time.