#0  0x00007f52ba455f3d in nanosleep () from /lib/x86_64-linux-gnu/libc.so.6
#1  0x00007f52ba455dd4 in sleep () from /lib/x86_64-linux-gnu/libc.so.6
#2  0x00007f52b4006425 in ah_crap_handler (signum=11)
    at /home/matt/Downloads/firefox-42.0/toolkit/xre/nsSigHandlers.cpp:103
#3  0x00007f52b3fe9312 in nsProfileLock::FatalSignalHandler (signo=11, info=0x7fff8150cef0, context=0x7fff8150cdc0)
    at /home/matt/Downloads/firefox-42.0/toolkit/profile/nsProfileLock.cpp:195
#4  0x00007f52b4e67a39 in AsmJSFaultHandler (signum=11, info=0x7fff8150cef0, context=0x7fff8150cdc0)
    at /home/matt/Downloads/firefox-42.0/js/src/asmjs/AsmJSSignalHandlers.cpp:1135
#5  <signal handler called>
#6  0x00007f52b00e4c7a in Checker::StartReadOp (this=0x7f528b5a0073)
    at /home/matt/Downloads/firefox-42.0/xpcom/build/../glue/pldhash.h:128
#7  0x00007f52b00e4806 in PLDHashTable::Iterator::Iterator (this=0x7fff8150d2e0, aTable=0x7f528b5a004b)
    at /home/matt/Downloads/firefox-42.0/xpcom/glue/pldhash.cpp:848
#8  0x00007f52b0d897a6 in Native2WrappedNativeMap::Iter (this=0x7f529a0d4b30)
    at /home/matt/Downloads/firefox-42.0/js/xpconnect/src/XPCMaps.h:152
#9  0x00007f52b0d7d259 in XPCWrappedNativeScope::TraceWrappedNativesInAllScopes (trc=0x7fff8150d438, 
    rt=0x7f52a064e000) at /home/matt/Downloads/firefox-42.0/js/xpconnect/src/XPCWrappedNativeScope.cpp:471
#10 0x00007f52b0d1ddf5 in XPCJSRuntime::TraceAdditionalNativeGrayRoots (this=0x7f52a064e000, trc=0x7fff8150d438)
    at /home/matt/Downloads/firefox-42.0/js/xpconnect/src/XPCJSRuntime.cpp:565
#11 0x00007f52affd3159 in mozilla::CycleCollectedJSRuntime::TraceNativeGrayRoots (this=0x7f52a064e000, 
    aTracer=0x7fff8150d438) at /home/matt/Downloads/firefox-42.0/xpcom/base/CycleCollectedJSRuntime.cpp:802
#12 0x00007f52affd2e0d in mozilla::CycleCollectedJSRuntime::TraceGrayJS (aTracer=0x7fff8150d438, 
    aData=0x7f52a064e000) at /home/matt/Downloads/firefox-42.0/xpcom/base/CycleCollectedJSRuntime.cpp:683
#13 0x00007f52b524230a in js::gc::GCRuntime::bufferGrayRoots (this=0x7f52a06743d8)
    at /home/matt/Downloads/firefox-42.0/js/src/gc/RootMarking.cpp:442
#14 0x00007f52b5647823 in js::gc::GCRuntime::beginMarkPhase (this=0x7f52a06743d8, 
    reason=JS::gcreason::SET_NEW_DOCUMENT) at /home/matt/Downloads/firefox-42.0/js/src/jsgc.cpp:3943
#15 0x00007f52b564e5f7 in js::gc::GCRuntime::incrementalCollectSlice (this=0x7f52a06743d8, budget=..., 
    reason=JS::gcreason::SET_NEW_DOCUMENT) at /home/matt/Downloads/firefox-42.0/js/src/jsgc.cpp:5818
#16 0x00007f52b564ef45 in js::gc::GCRuntime::gcCycle (this=0x7f52a06743d8, incremental=true, budget=..., 
    reason=JS::gcreason::SET_NEW_DOCUMENT) at /home/matt/Downloads/firefox-42.0/js/src/jsgc.cpp:6063
#17 0x00007f52b564f681 in js::gc::GCRuntime::collect (this=0x7f52a06743d8, incremental=true, budget=..., 
    reason=JS::gcreason::SET_NEW_DOCUMENT) at /home/matt/Downloads/firefox-42.0/js/src/jsgc.cpp:6177
#18 0x00007f52b564faea in js::gc::GCRuntime::startGC (this=0x7f52a06743d8, gckind=GC_NORMAL, 
    reason=JS::gcreason::SET_NEW_DOCUMENT, millis=0) at /home/matt/Downloads/firefox-42.0/js/src/jsgc.cpp:6246
#19 0x00007f52b5652836 in JS::StartIncrementalGC (rt=0x7f52a0674000, gckind=GC_NORMAL, 
    reason=JS::gcreason::SET_NEW_DOCUMENT, millis=0) at /home/matt/Downloads/firefox-42.0/js/src/jsgc.cpp:7096
#20 0x00007f52b16d8556 in nsJSContext::GarbageCollectNow (aReason=JS::gcreason::SET_NEW_DOCUMENT, 
    aIncremental=nsJSContext::IncrementalGC, aShrinking=nsJSContext::NonShrinkingGC, aSliceMillis=0)
    at /home/matt/Downloads/firefox-42.0/dom/base/nsJSEnvironment.cpp:1332
#21 0x00007f52b16d96c5 in GCTimerFired (aTimer=0x7f529a0cdec0, aClosure=0x2a)
    at /home/matt/Downloads/firefox-42.0/dom/base/nsJSEnvironment.cpp:1832
#22 0x00007f52b008a97e in nsTimerImpl::Fire (this=0x7f529a0cdec0)
    at /home/matt/Downloads/firefox-42.0/xpcom/threads/nsTimerImpl.cpp:437
#23 0x00007f52b0081567 in nsTimerEvent::Run (this=0x7f528d35f0b0)
    at /home/matt/Downloads/firefox-42.0/xpcom/threads/TimerThread.cpp:267
#24 0x00007f52b008611a in nsThread::ProcessNextEvent (this=0x7f52ba13d7c0, aMayWait=false, aResult=0x7fff8150daef)
    at /home/matt/Downloads/firefox-42.0/xpcom/threads/nsThread.cpp:867
#25 0x00007f52b00e2bec in NS_ProcessNextEvent (aThread=0x7f52ba13d7c0, aMayWait=false)
    at /home/matt/Downloads/firefox-42.0/xpcom/glue/nsThreadUtils.cpp:277
#26 0x00007f52b05cd53c in mozilla::ipc::MessagePump::Run (this=0x7f52a6b57e00, aDelegate=0x7f52ba172da0)
    at /home/matt/Downloads/firefox-42.0/ipc/glue/MessagePump.cpp:95
#27 0x00007f52b055d965 in MessageLoop::RunInternal (this=0x7f52ba172da0)
    at /home/matt/Downloads/firefox-42.0/ipc/chromium/src/base/message_loop.cc:234
#28 0x00007f52b055d8fa in MessageLoop::RunHandler (this=0x7f52ba172da0)
    at /home/matt/Downloads/firefox-42.0/ipc/chromium/src/base/message_loop.cc:227
#29 0x00007f52b055d88b in MessageLoop::Run (this=0x7f52ba172da0)
    at /home/matt/Downloads/firefox-42.0/ipc/chromium/src/base/message_loop.cc:201
#30 0x00007f52b3146dec in nsBaseAppShell::Run (this=0x7f529d010480)
    at /home/matt/Downloads/firefox-42.0/widget/nsBaseAppShell.cpp:165
#31 0x00007f52b3f5c17b in nsAppStartup::Run (this=0x7f529d026920)
    at /home/matt/Downloads/firefox-42.0/toolkit/components/startup/nsAppStartup.cpp:280
#32 0x00007f52b3ffd34b in XREMain::XRE_mainRun (this=0x7fff8150dec0)
    at /home/matt/Downloads/firefox-42.0/toolkit/xre/nsAppRunner.cpp:4287
#33 0x00007f52b3ffd71c in XREMain::XRE_main (this=0x7fff8150dec0, argc=4, argv=0x7fff8150f3c8, 
    aAppData=0x7fff8150e0e0) at /home/matt/Downloads/firefox-42.0/toolkit/xre/nsAppRunner.cpp:4380
#34 0x00007f52b3ffd9f9 in XRE_main (argc=4, argv=0x7fff8150f3c8, aAppData=0x7fff8150e0e0, aFlags=0)
    at /home/matt/Downloads/firefox-42.0/toolkit/xre/nsAppRunner.cpp:4482
#35 0x00000000004051a4 in do_main (argc=4, argv=0x7fff8150f3c8, xreDirectory=0x7f52ba154840)
    at /home/matt/Downloads/firefox-42.0/browser/app/nsBrowserApp.cpp:212
#36 0x00000000004055af in main (argc=4, argv=0x7fff8150f3c8)
    at /home/matt/Downloads/firefox-42.0/browser/app/nsBrowserApp.cpp:399