This bug was filed from the Socorro interface and is report bp-37f39820-7564-4cf0-bcef-be5830180814. ============================================================= Top 10 frames of crashing thread: 0 @0x7fff7752920a 1 XUL mozilla::recordreplay::RR_mach_msg toolkit/recordreplay/ProcessRedirect.h:119 2 XUL google_breakpad::ReceivePort::WaitForMessage toolkit/crashreporter/google-breakpad/src/common/mac/MachIPC.mm:249 3 XUL google_breakpad::CrashGenerationClient::RequestDumpForException toolkit/crashreporter/breakpad-client/mac/crash_generation/crash_generation_client.cc:77 4 XUL google_breakpad::ExceptionHandler::WriteMinidumpWithException toolkit/crashreporter/breakpad-client/mac/handler/exception_handler.cc:382 5 XUL google_breakpad::ExceptionHandler::WriteForwardedExceptionMinidump toolkit/crashreporter/breakpad-client/mac/handler/exception_handler.cc:651 6 XUL mozilla::recordreplay::child::ReportFatalError toolkit/recordreplay/ipc/ChildIPC.cpp:315 7 XUL RecordReplayInterface_InternalRecordReplayAssert toolkit/recordreplay/ProcessRecordReplay.cpp:474 8 XUL mozilla::recordreplay::RecordReplayAssert mfbt/RecordReplay.h:474 9 XUL mozilla::recordreplay::RR_mach_absolute_time toolkit/recordreplay/ProcessRedirect.h:193 ============================================================= There are 6 crashes (from 1 installation) in nightly 63 with buildid 20180814100100. In analyzing the backtrace, the regression may have been introduced by patch [1] to fix bug 1481009. [1] https://hg.mozilla.org/mozilla-central/rev?node=5b2072d947e6

Bug 1481009 enables the crash reporter in recording/replaying processes, and from the stack it looks like everything there is working properly and this crash is for a problem in a replaying process (which previously would not have been reported at all). Do you know if it's possible to see the .extra file from the minidump associated with these crashes? There should be a RecordReplayError entry there but it is not in the Metadata page of the crash report.

I've been getting this crash locally as well. It looks like a regression from bug 1397297 --- SliceBudget behaves non-deterministically when recording/replaying, so the SnowWhiteKiller behaves non-deterministically as a result. This patch ignores the slice budget when recording/replaying.

Pushed by bhackett@mozilla.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/3d462cf06ef0 Run SnowWhiteKiller non-incrementally when recording/replaying, r=mccr8.