Filed by: csabou [at] mozilla.com https://treeherder.mozilla.org/logviewer.html#?job_id=186659220&repo=mozilla-inbound https://queue.taskcluster.net/v1/task/Xjirj_coR_aVVdHW-9EN3g/runs/0/artifacts/public/logs/live_backing.log https://hg.mozilla.org/mozilla-central/raw-file/tip/layout/tools/reftest/reftest-analyzer.xhtml#logurl=https://queue.taskcluster.net/v1/task/Xjirj_coR_aVVdHW-9EN3g/runs/0/artifacts/public/logs/live_backing.log&only_show_unexpected=1 [task 2018-07-05T16:51:28.727Z] INFO - REFTEST TEST-UNEXPECTED-FAIL | file:///builds/worker/workspace/build/tests/reftest/tests/layout/style/crashtests/1383001.html | assertion count 1 is more than expected 0 assertions [task 2018-07-05T16:51:28.728Z] INFO - REFTEST TEST-START | file:///builds/worker/workspace/build/tests/reftest/tests/layout/style/crashtests/1383001-2.html [task 2018-07-05T16:51:28.728Z] INFO - REFTEST TEST-LOAD | file:///builds/worker/workspace/build/tests/reftest/tests/layout/style/crashtests/1383001-2.html | 2915 / 3619 (80%)

The assertion here is: ###!!! ASSERTION: Tried to delete invalid animation: 'Error', file /builds/worker/workspace/build/src/gfx/layers/wr/WebRenderBridgeParent.cpp, line 520 Longer snippet from the log: ======= [task 2018-07-05T16:51:27.574Z] INFO - REFTEST TEST-LOAD | file:///builds/worker/workspace/build/tests/reftest/tests/layout/style/crashtests/1383001.html | 2914 / 3619 (80%) [task 2018-07-05T16:51:27.610Z] INFO - ++DOMWINDOW == 67 (0x7ff061ffa000) [pid = 1040] [serial = 8329] [outer = 0x7ff08ac98800] [task 2018-07-05T16:51:27.619Z] INFO - [Parent 935, Compositor] ###!!! ASSERTION: Tried to delete invalid animation: 'Error', file /builds/worker/workspace/build/src/gfx/layers/wr/WebRenderBridgeParent.cpp, line 520 [task 2018-07-05T16:51:27.621Z] INFO - #01: mozilla::layers::CompositorBridgeParent::NotifyPipelineRendered(mozilla::wr::PipelineId const&, mozilla::wr::Epoch const&, mozilla::TimeStamp&, mozilla::TimeStamp&) [gfx/layers/ipc/CompositorBridgeParent.cpp:2186] [task 2018-07-05T16:51:27.622Z] INFO - [task 2018-07-05T16:51:27.623Z] INFO - #02: mozilla::wr::NotifyDidRender [gfx/webrender_bindings/RenderThread.cpp:303] [task 2018-07-05T16:51:27.625Z] INFO - [task 2018-07-05T16:51:27.626Z] INFO - #03: RunnableFunction<void (*)(mozilla::layers::CompositorBridgeParent*, mozilla::wr::WrPipelineInfo, mozilla::TimeStamp, mozilla::TimeStamp), mozilla::Tuple<mozilla::layers::CompositorBridgeParent*, mozilla::wr::WrPipelineInfo, mozilla::TimeStamp, mozilla::TimeStamp> >::Run() [ipc/chromium/src/base/task.h:38] [task 2018-07-05T16:51:27.629Z] INFO - [task 2018-07-05T16:51:27.630Z] INFO - #04: MessageLoop::RunTask(already_AddRefed<nsIRunnable>) [xpcom/base/nsCOMPtr.h:638] [task 2018-07-05T16:51:27.630Z] INFO - [task 2018-07-05T16:51:27.631Z] INFO - #05: MessageLoop::DeferOrRunPendingTask(MessageLoop::PendingTask&&) [ipc/chromium/src/base/message_loop.cc:459] [task 2018-07-05T16:51:27.632Z] INFO - [task 2018-07-05T16:51:27.634Z] INFO - #06: MessageLoop::DoWork() [ipc/chromium/src/base/message_loop.cc:534] [task 2018-07-05T16:51:27.635Z] INFO - [task 2018-07-05T16:51:27.636Z] INFO - #07: base::MessagePumpDefault::Run(base::MessagePump::Delegate*) [ipc/chromium/src/base/message_pump_default.cc:39] [task 2018-07-05T16:51:27.636Z] INFO - [task 2018-07-05T16:51:27.637Z] INFO - #08: MessageLoop::RunInternal() [ipc/chromium/src/base/message_loop.cc:326] [task 2018-07-05T16:51:27.637Z] INFO - [task 2018-07-05T16:51:27.638Z] INFO - #09: MessageLoop::Run() [ipc/chromium/src/base/message_loop.cc:297] [task 2018-07-05T16:51:27.638Z] INFO - [task 2018-07-05T16:51:27.639Z] INFO - #10: base::Thread::ThreadMain() [ipc/chromium/src/base/thread.cc:184] [task 2018-07-05T16:51:27.639Z] INFO - [task 2018-07-05T16:51:27.640Z] INFO - #11: ThreadFunc [ipc/chromium/src/base/platform_thread_posix.cc:40] [task 2018-07-05T16:51:27.640Z] INFO - [task 2018-07-05T16:51:27.640Z] INFO - #12: libpthread.so.0 + 0x76ba [task 2018-07-05T16:51:27.641Z] INFO - [task 2018-07-05T16:51:27.641Z] INFO - #13: libc.so.6 + 0x10741d [task 2018-07-05T16:51:27.642Z] INFO - [task 2018-07-05T16:51:27.642Z] INFO - #14: ??? (???:???)

I am not able to reproduce this failure in test-verify: https://treeherder.mozilla.org/#/jobs?repo=mozilla-inbound&filter-searchStr=linux%20debug%20qr%20verify&tochange=9b9ffa4c105daf1a69e2817cf5d221ee54600ad1&fromchange=51c5667299a2bdae23145308aa621340f92832aa