I tried to find the faulting code (hard because ASLR gives you 254 possible locations and we haven't added any code to allow us to adjust for this) and found one solid candidate: NamespaceDetailsTransient::notifyOfWriteOp() at line 537 in db/namespace_details.h.
/* you must notify the cache if you are doing writes, as query plan utility will change */
if ( _qcCache.empty() )
if ( ++_qcWriteCount >= 100 ) // this is the line matching the access violation
I tried running the test on my home machine and was not able to duplicate the crash. It is possible that this is a compiler bug, broken in the original Visual Studio 2010 run by the Buildbot but fixed in the Service Pack 1 version running on my machine, but that is a guess and probably wishful thinking.