Crash related to 4k video playback on 4.18

Hi we have recently upgraded our project to 4.18 from 4.16.3. I’m experiencing a random crash issues, this crash can happen anywhere between 15-50+ minute into our application while playing 4k videos in VR, Not sure if this is a know issue or something particular to our project, also it seems like only one machine: a laptop with Nvidia 1060 is affected, other pcs with radeaon cards ran without issues so far. For now we’re going to use 4.17.2 instead, which doesn’t seem to have this issue.

here’s the call stack for the video crash:

g:/epicgames/unrealengine_418/engine/source/runtime/slatecore/private/widgets/swidget.cpp(493) SWidget::SlatePrepass
g:/epicgames/unrealengine_418/engine/source/runtime/slate/private/framework/application/slateapplication.cpp(1343) PrepassWindowAndChildren
g:/epicgames/unrealengine_418/engine/source/runtime/slate/private/framework/application/slateapplication.cpp(1392) FSlateApplication::DrawPrepass
g:/epicgames/unrealengine_418/engine/source/runtime/slate/private/framework/application/slateapplication.cpp(1433) FSlateApplication::PrivateDrawWindows
g:/epicgames/unrealengine_418/engine/source/runtime/slate/private/framework/application/slateapplication.cpp(1777) FSlateApplication::TickApplication
g:/epicgames/unrealengine_418/engine/source/runtime/slate/private/framework/application/slateapplication.cpp(1602) FSlateApplication::Tick
g:/epicgames/unrealengine_418/engine/source/runtime/launch/private/launchengineloop.cpp(3378) FEngineLoop::Tick
g:/epicgames/unrealengine_418/engine/source/runtime/launch/private/launch.cpp(166) GuardedMain
g:/epicgames/unrealengine_418/engine/source/runtime/launch/private/windows/launchwindows.cpp(134) GuardedMainWrapper
g:/epicgames/unrealengine_418/engine/source/runtime/launch/private/windows/launchwindows.cpp(210) WinMain
f:/dd/vctools/crt/vcstartup/src/startup/exe_common.inl(253) __scrt_common_main_seh

  • kernel32!BaseThreadInitThunk
  • ntdll!RtlUserThreadStart

Wondering if anyone knows anything or can help out with this, thanks!

The location of your crash suggests that the SWidget doing a prepass has been destroyed. Can you catch it in the debugger and see what the ‘this’ pointer looks like?