We have recently started getting this error but we are unable to find the reason behind it so far:
NullReferenceException: Object reference not set to an instance of an object
at Unity.Entities.EntityDataManager.IncrementComponentOrderVersion (Unity.Entities.Archetype* archetype, Unity.Entities.Chunk* chunk, Unity.Entities.SharedComponentDataManager sharedComponentDataManager) [0x0000c] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Entities\EntityDataManager.cs:1122
at Unity.Entities.EntityDataManager.SetSharedComponentDataIndex (Unity.Entities.ArchetypeManager archetypeManager, Unity.Entities.SharedComponentDataManager sharedComponentDataManager, Unity.Entities.Entity entity, System.Int32 typeIndex, System.Int32 newSharedComponentDataIndex) [0x0008f] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Entities\EntityDataManager.cs:1111
at Unity.Entities.EntityManager.SetSharedComponentDataBoxed (Unity.Entities.Entity entity, System.Int32 typeIndex, System.Int32 hashCode, System.Object componentData) [0x0002e] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Entities\EntityManager.cs:581
at Unity.Entities.EntityCommandBuffer.PlaybackChain (Unity.Entities.EntityManager mgr, Unity.Entities.ECBSharedPlaybackState& playbackState, Unity.Collections.NativeArray`1[T] chainStates, System.Int32 currentChain, System.Int32 nextChain) [0x00489] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Entities\EntityCommandBuffer.cs:1015
at Unity.Entities.EntityCommandBuffer.Playback (Unity.Entities.EntityManager mgr) [0x00233] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Entities\EntityCommandBuffer.cs:872
at Unity.Transforms.TransformSystem.UpdateDepth () [0x0010d] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Transforms\TransformSystem.cs:1006
at Unity.Transforms.TransformSystem.OnUpdate (Unity.Jobs.JobHandle inputDeps) [0x000a1] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Transforms\TransformSystem.cs:1166
at Unity.Entities.JobComponentSystem.InternalUpdate () [0x0005a] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Entities\ComponentSystem.cs:508
at Unity.Entities.ScriptBehaviourManager.Update () [0x00001] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Entities\ScriptBehaviourManager.cs:77
at Unity.Entities.ScriptBehaviourUpdateOrder+DummyDelagateWrapper.TriggerUpdate () [0x00001] in D:\Git\phantombrigade\Library\PackageCache\com.unity.entities@0.0.12-preview.20\Unity.Entities\ScriptBehaviourUpdateOrder.cs:703
(Filename: D:/Git/phantombrigade/Library/PackageCache/com.unity.entities@0.0.12-preview.20/Unity.Entities/EntityDataManager.cs Line: 1122)
What could cause the transform system/entity data manager to trip like that? If I’m not mistaken, the only operations we perform in frames around this error is attachment of Parent data components to some entities, and I don’t see how they can cause this.