I don't have any opinion about secure-or-not, but since every Web Audio crash bug I've seen has been, and nobody's around to tell me different, starting out that way. https://tbpl.mozilla.org/php/getParsedLog.php?id=24448771&full=1&branch=mozilla-inbound#error0 Rev4 MacOSX Snow Leopard 10.6 mozilla-inbound debug test mochitest-1 on 2013-06-21 18:11:10 PDT for push 086b4d0b6cc6 slave: talos-r4-snow-075 18:44:01 INFO - 153122 INFO TEST-START | /tests/content/media/webaudio/test/test_mixingRules.html 18:44:01 INFO - ++DOMWINDOW == 36 (0x1516c2ab8) [serial = 4737] [outer = 0x12d87dcd8] 18:44:04 WARNING - TEST-UNEXPECTED-FAIL | /tests/content/media/webaudio/test/test_mixingRules.html | Exited with code 1 during test run 18:44:04 INFO - INFO | automation.py | Application ran for: 0:31:11.751340 18:44:04 INFO - INFO | zombiecheck | Reading PID log: /var/folders/Hs/HsDn6a9SG8idoIya6p9mtE+++TI/-Tmp-/tmpO9CIXYpidlog 18:44:21 WARNING - PROCESS-CRASH | /tests/content/media/webaudio/test/test_mixingRules.html | application crashed [@ mozilla::MediaStreamGraphImpl::PrepareUpdatesToMainThreadState(bool)] 18:44:21 INFO - Crash dump filename: /var/folders/Hs/HsDn6a9SG8idoIya6p9mtE+++TI/-Tmp-/tmpui7NRo/minidumps/8939BBC9-466F-4CF7-BFCF-492C59900E93.dmp 18:44:21 INFO - Operating system: Mac OS X 18:44:21 INFO - 10.6.8 10K549 18:44:21 INFO - CPU: amd64 18:44:21 INFO - family 6 model 23 stepping 10 18:44:21 INFO - 2 CPUs 18:44:21 INFO - Crash reason: EXC_BAD_ACCESS / KERN_INVALID_ADDRESS 18:44:21 INFO - Crash address: 0x1cca6000 18:44:21 INFO - Thread 29 (crashed) 18:44:21 INFO - 0 XUL!mozilla::MediaStreamGraphImpl::PrepareUpdatesToMainThreadState(bool) [nsTArray.h:086b4d0b6cc6 : 371 + 0x7] 18:44:21 INFO - rbx = 0x000000014d8d4cc0 r12 = 0x0000000152fd8c08 18:44:21 INFO - r13 = 0x000000015436c648 r14 = 0x00000000000023e0 18:44:21 INFO - r15 = 0x000000015436c5c0 rip = 0x00000001023aa195 18:44:21 INFO - rsp = 0x00000001198a3c80 rbp = 0x00000001198a3cd0 18:44:21 INFO - Found by: given as instruction pointer in context 18:44:21 INFO - 1 XUL!mozilla::MediaStreamGraphImpl::RunThread() [MediaStreamGraph.cpp:086b4d0b6cc6 : 1130 + 0x9] 18:44:21 INFO - rbx = 0x000000000000000b r12 = 0x000000014d8d4d00 18:44:21 INFO - r13 = 0x000000015436c658 r14 = 0x000000015436c5c0 18:44:21 INFO - r15 = 0x000000015436c610 rip = 0x00000001023aacda 18:44:21 INFO - rsp = 0x00000001198a3ce0 rbp = 0x00000001198a3dc0 18:44:21 INFO - Found by: call frame info 18:44:21 INFO - 2 XUL!mozilla::(anonymous namespace)::MediaStreamGraphThreadRunnable::Run() [MediaStreamGraph.cpp:086b4d0b6cc6 : 1229 + 0x8] 18:44:21 INFO - rbx = 0x0000000150031c40 r12 = 0x0000000000000000 18:44:21 INFO - r13 = 0x000000000000d907 r14 = 0x0000000150031c80 18:44:21 INFO - r15 = 0x0000000000000001 rip = 0x00000001023af60d 18:44:21 INFO - rsp = 0x00000001198a3dd0 rbp = 0x00000001198a3dd0 18:44:21 INFO - Found by: call frame info 18:44:21 INFO - 3 XUL!nsThread::ProcessNextEvent(bool, bool*) [nsThread.cpp:086b4d0b6cc6 : 626 + 0x5] 18:44:21 INFO - rbx = 0x0000000150031c40 r12 = 0x0000000000000000 18:44:21 INFO - r13 = 0x000000000000d907 r14 = 0x0000000150031c80 18:44:21 INFO - r15 = 0x0000000000000001 rip = 0x00000001034e657f 18:44:21 INFO - rsp = 0x00000001198a3de0 rbp = 0x00000001198a3e80 18:44:21 INFO - Found by: call frame info 18:44:21 INFO - 4 XUL!NS_ProcessNextEvent(nsIThread*, bool) [nsThreadUtils.cpp:086b4d0b6cc6 : 238 + 0xc] 18:44:21 INFO - rbx = 0x0000000000000001 r12 = 0x0000000000000000 18:44:21 INFO - r13 = 0x000000000000d907 r14 = 0x0000000150031ca8 18:44:21 INFO - r15 = 0x0000000150031c40 rip = 0x0000000103483662 18:44:21 INFO - rsp = 0x00000001198a3e90 rbp = 0x00000001198a3ea0 18:44:21 INFO - Found by: call frame info 18:44:21 INFO - 5 XUL!nsThread::ThreadFunc(void*) [nsThread.cpp:086b4d0b6cc6 : 264 + 0xc] 18:44:21 INFO - rbx = 0x000000014ec45090 r12 = 0x0000000000000000 18:44:21 INFO - r13 = 0x000000000000d907 r14 = 0x0000000150031ca8 18:44:21 INFO - r15 = 0x0000000150031c40 rip = 0x00000001034e4e8d 18:44:21 INFO - rsp = 0x00000001198a3eb0 rbp = 0x00000001198a3ee0 18:44:21 INFO - Found by: call frame info 18:44:21 INFO - 6 libnss3.dylib!_pt_root + 0xe6 18:44:21 INFO - rbx = 0x0000000157c601b0 r12 = 0x0000000000000000 18:44:21 INFO - r13 = 0x000000000000d907 r14 = 0x0000000000000000 18:44:21 INFO - r15 = 0x0000000157c601b0 rip = 0x000000010051f697 18:44:21 INFO - rsp = 0x00000001198a3ef0 rbp = 0x00000001198a3f10 18:44:21 INFO - Found by: call frame info 18:44:21 INFO - 7 libnss3.dylib!null_signal_handler + 0xf 18:44:21 INFO - rip = 0x000000010051f5b0 rsp = 0x00000001198a3f10 18:44:21 INFO - rbp = 0x00000001198a3f10 18:44:21 INFO - Found by: stack scanning 18:44:21 INFO - 8 libSystem.B.dylib + 0x39fd5 18:44:21 INFO - rip = 0x00007fff81695fd6 rsp = 0x00000001198a3f20 18:44:21 INFO - rbp = 0x00000001198a3f50 18:44:21 INFO - Found by: stack scanning 18:44:21 INFO - 9 libSystem.B.dylib + 0x39e88 18:44:21 INFO - rip = 0x00007fff81695e89 rsp = 0x00000001198a3f60 18:44:21 INFO - rbp = 0x00000001198a3f78 18:44:21 INFO - Found by: stack scanning 18:44:21 INFO - 10 libnss3.dylib!null_signal_handler + 0xf 18:44:21 INFO - rip = 0x000000010051f5b0 rsp = 0x00000001198a4050 18:44:21 INFO - Found by: stack scanning

My first guess is that this is a dupe of bug 884459. Note that it happened on the push before the patch to that bug.

Please reopen if this happens again on trunk. Thanks.