StacktraceTop: __GI___pthread_mutex_lock (mutex=0x0) at ../nptl/pthread_mutex_lock.c:66 crLockMutex (mutex=<optimized out>) at /build/buildd/virtualbox-4.3.6-dfsg/src/VBox/GuestHost/OpenGL/util/threads.c:166 crHashtableLock (h=<optimized out>) at /build/buildd/virtualbox-4.3.6-dfsg/src/VBox/GuestHost/OpenGL/util/hash.c:434 stubSyncThreadProc (ThreadSelf=0x1eb4a00, pvUser=<optimized out>) at /build/buildd/virtualbox-4.3.6-dfsg/src/VBox/Additions/common/crOpenGL/load.c:898 rtThreadMain (pThread=0x1eb4a00, NativeThread=<optimized out>, pszThreadName=<optimized out>) at /build/buildd/virtualbox-4.3.6-dfsg/src/VBox/Runtime/common/misc/thread.cpp:712
StacktraceTop: _pthread_ mutex_lock (mutex=0x0) at ../nptl/ pthread_ mutex_lock. c:66 buildd/ virtualbox- 4.3.6-dfsg/ src/VBox/ GuestHost/ OpenGL/ util/threads. c:166 buildd/ virtualbox- 4.3.6-dfsg/ src/VBox/ GuestHost/ OpenGL/ util/hash. c:434 0x1eb4a00, pvUser=<optimized out>) at /build/ buildd/ virtualbox- 4.3.6-dfsg/ src/VBox/ Additions/ common/ crOpenGL/ load.c: 898 <optimized out>, pszThreadName= <optimized out>) at /build/ buildd/ virtualbox- 4.3.6-dfsg/ src/VBox/ Runtime/ common/ misc/thread. cpp:712
__GI__
crLockMutex (mutex=<optimized out>) at /build/
crHashtableLock (h=<optimized out>) at /build/
stubSyncThreadProc (ThreadSelf=
rtThreadMain (pThread=0x1eb4a00, NativeThread=