Rev5 MacOSX Yosemite 10.10 mozilla-inbound debug test mochitest-1 https://treeherder.mozilla.org/logviewer.html#?job_id=10184133&repo=mozilla-inbound 21:47:01 WARNING - PROCESS-CRASH | dom/canvas/test/test_capture.html | application crashed [@ mozilla::detail::RefCounted<mozilla::gfx::SourceSurface, (mozilla::detail::RefCountAtomicity)1>::Release() const] 21:47:01 INFO - Crash dump filename: /var/folders/ql/zf453_qj7f3dprs4zvm9s2y800000w/T/tmpmAMlys.mozrunner/minidumps/6C82B192-5051-485D-AAA3-6E2C875F963B.dmp 21:47:01 INFO - Operating system: Mac OS X 21:47:01 INFO - 10.10.2 14C109 21:47:01 INFO - CPU: amd64 21:47:01 INFO - family 6 model 42 stepping 7 21:47:01 INFO - 8 CPUs 21:47:01 INFO - Crash reason: EXC_BAD_ACCESS / 0x0000000d 21:47:01 INFO - Crash address: 0x0 21:47:01 INFO - Thread 0 (crashed) 21:47:01 INFO - 0 XUL!mozilla::detail::RefCounted<mozilla::gfx::SourceSurface, (mozilla::detail::RefCountAtomicity)1>::Release() const [RefPtr.h:c7b2ecf508e6 : 130 + 0xb] 21:47:01 INFO - rbx = 0x0000000000000000 r12 = 0x00000001003316d0 21:47:01 INFO - r13 = 0x00000001003316d0 r14 = 0x0000000112951d30 21:47:01 INFO - r15 = 0x0000000112951d38 rip = 0x0000000101e4776e 21:47:01 INFO - rsp = 0x00007fff5fbfcf90 rbp = 0x00007fff5fbfcfb0 21:47:01 INFO - Found by: given as instruction pointer in context 21:47:01 INFO - 1 XUL!nsAutoRefTraits<nsMainThreadSourceSurfaceRef>::SurfaceReleaser::Run() [ImageContainer.h:c7b2ecf508e6 : 62 + 0xc] 21:47:01 INFO - rbx = 0x0000000000000000 r12 = 0x00000001003316d0 21:47:01 INFO - r13 = 0x00000001003316d0 r14 = 0x0000000000000000 21:47:01 INFO - r15 = 0x00000000003cfc7d rip = 0x00000001020319c1 21:47:01 INFO - rsp = 0x00007fff5fbfcfc0 rbp = 0x00007fff5fbfcfc0 21:47:01 INFO - Found by: call frame info 21:47:01 INFO - 2 XUL!nsThread::ProcessNextEvent(bool, bool*) [nsThread.cpp:c7b2ecf508e6 : 846 + 0x5] 21:47:01 INFO - rbx = 0x0000000000000000 r12 = 0x00000001003316d0 21:47:01 INFO - r13 = 0x00000001003316d0 r14 = 0x0000000000000000 21:47:01 INFO - r15 = 0x00000000003cfc7d rip = 0x00000001015039b0 21:47:01 INFO - rsp = 0x00007fff5fbfcfd0 rbp = 0x00007fff5fbfd0a0 21:47:01 INFO - Found by: call frame info 21:47:01 INFO - 3 XUL!NS_ProcessPendingEvents(nsIThread*, unsigned int) [nsThreadUtils.cpp:c7b2ecf508e6 : 207 + 0xe] 21:47:01 INFO - rbx = 0x0000000100309f60 r12 = 0x00000001003316d0 21:47:01 INFO - r13 = 0x00007fff5fbfd0b7 r14 = 0x0000000000000014 21:47:01 INFO - r15 = 0x00000000003cfc7d rip = 0x000000010152ea73 21:47:01 INFO - rsp = 0x00007fff5fbfd0b0 rbp = 0x00007fff5fbfd0e0 21:47:01 INFO - Found by: call frame info 21:47:01 INFO - 4 XUL!nsBaseAppShell::NativeEventCallback() [nsBaseAppShell.cpp:c7b2ecf508e6 : 99 + 0xe] 21:47:01 INFO - rbx = 0x0000000100309f60 r12 = 0x0000000000000000 21:47:01 INFO - r13 = 0x0000000000001803 r14 = 0x00000001003316d0 21:47:01 INFO - r15 = 0x0000000100309f00 rip = 0x00000001037ed357 21:47:01 INFO - rsp = 0x00007fff5fbfd0f0 rbp = 0x00007fff5fbfd110 21:47:01 INFO - Found by: call frame info 21:47:01 INFO - 5 XUL!nsAppShell::ProcessGeckoEvents(void*) [nsAppShell.mm:c7b2ecf508e6 : 377 + 0x7] 21:47:01 INFO - rbx = 0x00000001005006f0 r12 = 0x000000010062fbd0 21:47:01 INFO - r13 = 0x0000000000001803 r14 = 0x000000010062fbe8 21:47:01 INFO - r15 = 0x0000000100309f60 rip = 0x0000000103841f9e 21:47:01 INFO - rsp = 0x00007fff5fbfd120 rbp = 0x00007fff5fbfd160 21:47:01 INFO - Found by: call frame info

Looks like a task is dispatched to release a reference on the main thread but the given reference turns out to be null when this crashes. Browsing through the code I couldn't tell what caused task to be created with a null reference but re-triggering this try run will give us a better stack: https://treeherder.mozilla.org/#/jobs?repo=try&revision=27858b282cde

Fixed by bug 1176363.