UE4Editor/Mac crashes when opening project

UE4Editor for Mac crashes every time I try to load up our demo project. The project works fine on PC.

Steps to reproduce:

Load up SkookumScript demo project in UE4Editor 4.11 on Mac. Crashes at 96%. Every time.

Here is a link to the demo project:

You don’t need to have the SkookumScript plugin installed for the crash to happen. Just ignore any warnings about the missing SkookumScript plugin, and it will crash.

Thanks for your help!

P.S. here is the crash dump:

Application version 4.11.0-0
 ... built from changelist 2758231

OS version
Running 1 x64 processors
Exception was " SEGV_MAPERR at 0x10"

Source context from "engine/source/runtime/renderer/private/lightmaprendering.cpp"


GetPrecomputedLightingParameters(ERHIFeatureLevel::Type, FPrecomputedLightingParameters&, FIndirectLightingCache const*, FIndirectLightingCacheAllocation const*, FLightCacheInterface const*) Address = 0x119615aa5 [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Renderer/Private/LightMapRendering.cpp, line 125] [in UE4Editor-Renderer.dylib]
CreatePrecomputedLightingUniformBuffer(EUniformBufferUsage, ERHIFeatureLevel::Type, FIndirectLightingCache const*, FIndirectLightingCacheAllocation const*, FLightCacheInterface const*) Address = 0x119616770 [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Renderer/Private/LightMapRendering.cpp, line 243] [in UE4Editor-Renderer.dylib]
FPrimitiveSceneInfo::UpdatePrecomputedLightingBuffer() Address = 0x1198f0d46 [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Renderer/Private/PrimitiveSceneInfo.cpp, line 593] [in UE4Editor-Renderer.dylib]
FSceneRenderer::UpdatePrimitivePrecomputedLightingBuffers() Address = 0x1199eea45 [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Renderer/Private/SceneRendering.cpp, line 1663] [in UE4Editor-Renderer.dylib]
FDeferredShadingSceneRenderer::InitViews(FRHICommandListImmediate&) Address = 0x1199d4441 [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Renderer/Private/SceneVisibility.cpp, line 2759] [in UE4Editor-Renderer.dylib]
FDeferredShadingSceneRenderer::Render(FRHICommandListImmediate&) Address = 0x11945ce13 [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Renderer/Private/DeferredShadingRenderer.cpp, line 846] [in UE4Editor-Renderer.dylib]
FRendererModule::BeginRenderingViewFamily(FCanvas*, FSceneViewFamily*)::EURCMacro_FDrawSceneCommand::DoTask(ENamedThreads::Type, TRefCountPtr<FGraphEvent> const&) Address = 0x1199f07fe [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Renderer/Private/SceneRendering.cpp, line 1733] [in UE4Editor-Renderer.dylib]
TGraphTask<FRendererModule::BeginRenderingViewFamily(FCanvas*, FSceneViewFamily*)::EURCMacro_FDrawSceneCommand>::ExecuteTask(TArray<FBaseGraphTask*, FDefaultAllocator>&, ENamedThreads::Type) Address = 0x119a2547d [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Core/Public/Stats/.h, line 1537] [in UE4Editor-Renderer.dylib]
FNamedTaskThread::ProcessTasksNamedThread(int, bool) Address = 0x10a8224e2 [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Core/Private/Async/TaskGraph.cpp, line 148] [in UE4Editor-Core.dylib]
FNamedTaskThread::ProcessTasksUntilQuit(int) Address = 0x10a81dea5 [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Core/Private/GenericPlatform/GenericPlatformProcess.cpp, line 498] [in UE4Editor-Core.dylib]
FTaskGraphImplementation::ProcessThreadUntilRequestReturn(ENamedThreads::Type) Address = 0x10a81a87e [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Core/Private/Async/TaskGraph.cpp, line 1487] [in UE4Editor-Core.dylib]
RenderingThreadMain(FEvent*) Address = 0x1111575aa [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/RenderCore/Private/RenderingThread.cpp, line 310] [in UE4Editor-RenderCore.dylib]
FRenderingThread::Run() Address = 0x11116d4dd [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/RenderCore/Private/RenderingThread.cpp, line 434] [in UE4Editor-RenderCore.dylib]
FRunnableThreadPThread::Run() Address = 0x10a86d9c6 [/Users/zorro/Perforce/UnrealEngine/4.11/Engine/Source/Runtime/Core/Private/HAL/PThreadRunnableThread.cpp, line 26] [in UE4Editor-Core.dylib]
FRunnableThreadPThread::_ThreadProc(void*) Address = 0x10a831bcc [Runtime/Core/Private/GenericPlatform/../HAL/PThreadRunnableThread.h, line 168] [in UE4Editor-Core.dylib]
_pthread_body Address = 0x7fff8977905a (filename not found) [in libsystem_pthread.dylib]
_pthread_body Address = 0x7fff89778fd7 (filename not found) [in libsystem_pthread.dylib]
thread_start Address = 0x7fff897763ed (filename not found) [in libsystem_pthread.dylib]

Hi GreatGuru,

Following these steps, I was not able to recreate the crash:

  1. On Windows machine, launch UE4.11p4
  2. Select, “Open Project”
  3. Choose the 4.10 version and, when prompted, select “Make a Copy”
  4. Allow 4.11 copy to open and save
  5. Transfer 4.11 copy to a Mac and add to Unreal Projects
  6. Start Editor on Mac, select the 4.11 copy and open it (On this machine it had a clean preview of the project)

RESULT: Opens 4/4 without issues.

Please try these steps and let us know if the crash persists.



I replicated your exact steps and still get the exact same crash on the Mac.

Also curious if you were ever able to reproduce the crash on your end by directly downloading the project to the Mac and opening it there without pre-digesting it on a Windows machine?

I will make a debug build and see if I can catch the crash in the Xcode debugger to shed more light on what might be causing this.

I deleted the old project and downloaded the 4.10 version straight to the Mac. I then launched 4.11p4 and opened a copy of the original without a crash.

Also, can I tell from the source code which official preview I got? Version.h tells me only about the revision and patch but not the preview. I last synced to the GitHub 4.11 branch yesterday.

So it crashes for me in the “official” 4.11p4 launched from Epic Games Launcher as well.

And I got it to crash in a debug build in the Xcode debugger. What’s happening is there is a FIndirectLightingCache that claims it’s initialized but all of its textures are null. So then in LightMapRendering.cpp, line 125 it crashes while trying to access one of those null textures.

Sent you google chat invite maybe you can help me figuring out why it’s crashing via screen share or something.

I’m just thinking that the cause could be my graphics card not being up to spec. Got a pretty crappy card in my Mac (Radeon HD 2600 w/256MB of VRAM). Guessing maybe it’s failing to allocate enough VRAM or the card does not support the requested type of texture. If that’s the case would be nice to report a proper error though.

Only DirectX 11 compatible graphic cards running OpenGL 4.1 are supported for Macs. Please review the following link for other hardware requirements:

[Hardware and Software Specifications][1]

As you can see by this graph, your card is running OpenGl 3.3:


Thanks, ! New card (GTX 680) is already on the way.

Sounds good -just make sure, if you haven’t already, that your Mac also meets the other following minimum specifications:

  • Operating System Mac OS X 10.9.2
  • Processor Quad-core Intel, 2.5 GHz or faster
  • Memory 8 GB RAM

I was going to buy a 2011 quad core, 8GB MacBook Pro BUT is there a problem with an older graphics card compatibility??

I was going to buy a 2011 quad core, 8GB MacBook Pro BUT is there a problem with an older graphics card compatibility??

Find the computer model on this site:


Look up the GPU in the models specifications, and then find the GPU on this link:


If the OpenGL/GLSL version is 3.3/3.30 respectively, it will not run UE4. OpenGL/GLSL must be 4.1/4.10 on for Macs.

Yup, I cannot run UE4 11 but I am OK with UE4 10 because:

I have a MacBook Air “Core i5” 1.6 11" (Mid-2011)MacBookAir4,1 which only has OpenGL Version 3.3
and OpenGL Version 3.3 is not enough for UE4 11 it needs to be OpenGL version 4.1


Yup, I cannot run UE4 11 but I am OK with UE4 10 because:

I have a MacBook Air “Core i5” 1.6 11" (Mid-2011)MacBookAir4,1 which only has OpenGL Version 3.3
and OpenGL Version 3.3 is not enough for UE4 11 it needs to be OpenGL version 4.1


Just to be clear, Open GL 3.3 is not supported on Macs for any version of UE4. If you are currently running UE4.10 on a machine with the specs you have listed, this is not typical and you may experience issues with more complex projects down the road.