Crash when connecting a Gear VR binary over the network as client & fix

Running a Gear VR binary as client will result in a crash shortly after it connects to a listen server. It does not matter whether the server runs on a PC (Windows 8.1) or on another Android device. Connecting with a PC (Windows 8.1) to a Gear VR binary running as listen server works fine. I ran the Gear VR binary on a Samsung S6.

Here (LINK) is the relevant part of a GDB session, showing the traceback.

Without a listen server the Gear VR client will not crash.

After connecting to a listen server a Gear VR client will eventually call FGearVR::DrawDebug() (in Engine/Plugins/Runtime/GearVR/Source/GearVR/Private/GearVR.cpp). That method contains a call to DrawSeaOfCubes() which results in a crash. I expect that the cause is that Canvas->SceneView is invalid at that time, but I have not verified that yet. Anyway, commenting that call appears to have no adverse effects, but makes a Gear VR client run (after connecting) without crashing.

Could you fix that in the next release of Unreal?

Hello dbjh,

I was able to reproduce this issue on our end. I have written up a report ( UE-24339) and I have submitted it to the developers for further consideration. I will provide updates with any pertinent information as it becomes available. Thank you for your time and information.

Make it a great day


Any news on the subject?

I don’t really know where I can follow the task UE-24339.

Hello monsieurgustav,

I went ahead and double checked on this issue for you, it appears as though this issue has been resolved internally and that the solution will be available in a later release of the engine. I hope that this information helps.

Make it a great day