Logic tests hang in -[MKTileCache init] () after linking AssetsLibrary.framework

My iOS app has a bunch of simple logic tests, which we run in a continuous integration using buildot.

Recently I started linking the AssetsLibrary framework to both the main app, and to the logic tests. The logic tests include classes from the main application, which use the framework in some methods, but these are not called in the logic tests.

Ever since, the unit tests on our buildbot are hanging, pretty early in the process. Gdb'ing to octest when this happens, there seems to be some sort of thread dead-lock in MKTileCache (which I don't use anywhere):

(gdb) thread apply all bt

Thread 3 (process 77496):
#0  0x00495ff7 in -[__NSArrayM objectAtIndex:] ()
#1  0x000528fa in -[NSFileManager(NSURLExtras)     _web_createDirectoryAtPathWithIntermediateDirectories:attributes:] ()
#2  0x052a554c in TileCachePrivate::runCacheThread ()
#3  0x052a5702 in _runCacheThread ()
#4  0x95f47259 in _pthread_start ()
#5  0x95f470de in thread_start ()

Thread 2 (process 77496):
#0  0x95f40382 in kevent ()
#1  0x00c1ff36 in _dispatch_mgr_invoke ()
#2  0x00c20333 in _dispatch_queue_invoke ()
#3  0x00c20593 in _dispatch_worker_thread2 ()
#4  0x95f3f781 in _pthread_wqthread ()
#5  0x95f3f5c6 in start_wqthread ()

Thread 1 (process 77496):
#0  0x95f47aa2 in __semwait_signal ()
#1  0x95f4775e in _pthread_cond_wait ()
#2  0x95f493f8 in pthread_cond_wait$UNIX2003 ()
#3  0x052a543d in TileCachePrivate::TileCachePrivate ()
#4  0x052a68de in -[MKTileCache init] ()
#5  0x052a51f8 in +[MKTileCache sharedCache] ()
#6  0x0529eb7b in +[MKMapTileView initialize] ()
#7  0x002cfd9b in _class_initialize ()
#8  0x002d773f in prepareForMethodLookup ()
#9  0x002ce069 in lookUpMethod ()
#10 0x002ce1d6 in _class_lookupMethodAndLoadCache ()
#11 0x002e10e3 in objc_msgSend ()
#12 0x20108824 in +[NSObject(SenTestRuntimeUtilities) senAllSubclasses] ()
#13 0x201074a7 in +[SenTestSuite updateCache] ()
#14 0x20107443 in +[SenTestSuite suiteForBundleCache] ()
#15 0x201073a4 in +[SenTestSuite testSuiteForBundlePath:] ()
#16 0x2010606b in +[SenTestProbe specifiedTestSuite] ()
#17 0x20106792 in +[SenTestProbe runTests:] ()
#18 0x000023c7 in ?? ()
#19 0x000025f2 in ?? ()
#20 0x0000209a in ?? ()
#21 0x00002049 in ?? ()

Has anyone seen anything like that?