iOS Crashes on map load

iOS seems to crash on map load for a few levels in our game. Other levels load fine, and Android works without crashing. Here is the stack trace:

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[2018.12.11-04.41.14:835][905]LogIOS: Error: 0x05730f94 DMLmobile!FGenericPlatformStackWalk::StackWalkAndDump(char*, unsigned long, int, void*) [UnknownFile])
0x05e1a358 DMLmobile!SignalHandler(int, __siginfo*, void*) [UnknownFile])
0xadc859f0 libsystem_platform.dylib!() [UnknownFile])
0x07a8e8f0 DMLmobile!FArrowSceneProxy::GetDynamicMeshElements(TArray const&, FSceneViewFamily const&, unsigned int, FMeshElementCollector&) const [UnknownFile])
0x06ea5edc DMLmobile!FSceneRenderer::GatherDynamicMeshElements(TArray&, FScene const*, FSceneViewFamily const&, TArray > const&, TArray > const&, TArray > const&, FMeshElementCollector&) [UnknownFile])
0x06eaff48 DMLmobile!FSceneRenderer::ComputeViewVisibility(FRHICommandListImmediate&) [UnknownFile])
0x06ab5204 DMLmobile!FMobileSceneRenderer::InitViews(FRHICommandListImmediate&) [UnknownFile])
0x06ab6524 DMLmobile!FMobileSceneRenderer::Render(FRHICommandListImmediate&) [UnknownFile])
0x06e9e694 DMLmobile!FRendererModule::BeginRenderingViewFamily(FCanvas*, FSceneViewFamily*)::EURCMacro_FDrawSceneCommand::DoTask(ENamedThreads::Type, TRefCountPtr const&) [UnknownFile])
0x06edbd58 DMLmobile!TGraphTask::ExecuteTask(TArray&, ENamedThreads::Type) [UnknownFile])
0x056f608c DMLmobile!FNamedTaskThread::ProcessTasksNamedThread(int, bool) [UnknownFile])
0x056f490c DMLmobile!FNamedTaskThread::ProcessTasksUntilQuit(int) [UnknownFile])
0x056f19ec DMLmobile!FTaskGraphImplementation::ProcessThreadUntilRequestReturn(ENamedThreads::Type) [UnknownFile])
0x06768464 DMLmobile!RenderingThreadMain(FEvent*) [UnknownFile])
0x06775ec0 DMLmobile!FRenderingThread::Run() [UnknownFile])
0x05772afc DMLmobile!FRunnableThreadPThread::Run() [UnknownFile])
0x0575bf34 DMLmobile!FRunnableThreadPThread::_ThreadProc(void*) [UnknownFile])
0xadc9425c libsystem_pthread.dylib!() [UnknownFile])
0xadc941bc libsystem_pthread.dylib!_pthread_start() [UnknownFile])
0xadc97cf4 libsystem_pthread.dylib!thread_start() [UnknownFile])

I figured this out finally. There were some assets in the levels which were corrupted or something. I had to painstakingly delete assets from the level, package the game, test it on my iphone and see if it would crash or not.
To speed up the process I would delete half the assets of the level and test. If it runs I know the corrupted asset was one of the ones I deleted. So then I delete half of those, and continually delete half until I have finally deduced which asset is causing the problem.

This issue was hell to debug as multiple levels had corrupted assets, but each level had different assets that were corrupted. Wouldn’t wish it on anybody.