Resolved IL2CPP AOT exceptions when loading SubScenes in a build

I recently upgraded from 2020.3.8f1 to 2021.2.0f1. Trying to load SubScenes in a build now throws the following exceptions. The build is using IL2CPP and the WindowsBuildConfiguration build pipeline.

Code (CSharp):

1. ExecutionEngineException: Attempting to call method 'Unity.Entities.FastEquality+GetHashCodeImpl`1[[Unity.Entities.SceneSection, Unity.Entities, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null]]::GetHashCodeFunc' for which no ahead of time (AOT) code was generated.
2. ExecutionEngineException: Attempting to call method 'Unity.Entities.FastEquality+CompareImpl`1[[Unity.Entities.SceneTag, Unity.Entities, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null]]::CompareFunc' for which no ahead of time (AOT) code was generated.

This issue also reproduces in a blank HDRP project in 2021.2.2f1

Anyone running into this problem?
I've tried to add AOT stub code to pre-define Unity.Entities.SceneSection and SceneTag for the FastEquality generic methods, but nothing is working. Most of the class is private, so I cannot access GetHashCodeImpl or CompareImpl directly.
I have also tried adding Unity.Entities namespace to link.xml. That didn't fix it. I don't think its a stripping issue anyways... rather IL2CPP has to explicitly define which types will be called by generic methods.

Thanks

 

Same issue here on Unity 2021.2.5f1... I got this error via logcat on android for my project:

Error Unity ExecutionEngineException: Attempting to call method 'Unity.Entities.FastEquality+CompareImpl`1[[Unity.Rendering.FrozenRenderSceneTag, Unity.Rendering.Hybrid, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null]]::CompareFunc' for which no ahead of time (AOT) code was generated.

I havn't found a solution yet.

 

same error here. Upgraded to Unity 2021.2 from 2021.1 where everything worked fine

 

For anyone who runs into this error: I was able to get rid of this error by changing the IL2CPP Code Generation (Build Settings window) to "Faster (smaller) builds". I also changed code stripping level to minimal, but I'm not sure if that had an effect

 

very nice... this also solved the issue on my side.

Big thanks

 

This fixed my issue! Thanks everyone for the help

 

hi , where is that blog ? and how can 2021.3.x work around this issue without change IL2CPP Code Generation option

 

try write some code in monobehavior but still got same error, and error only exist in android build , not in ios build.
........
var sections = new List<SceneSection>();
EntityManager.GetAllUniqueSharedComponentData(sections);
for(int i = 0; i < sections.Count;i++)
{
var section = sections;
var index = TypeManager.GetTypeIndex<SceneSection>();
Debug.LogError($"SceneSection GetTypeIndex {index}");
var type_info_m = TypeManager.GetTypeInfo(index);
Debug.LogError($"SceneSection TypeManager type_info {type_info_m}");
var type_info_f = TypeManager.GetFastEqualityTypeInfo(type_info_m);
Debug.LogError($"SceneSection FastEquality type_info GetHashFn {type_info_f.GetHashFn}");
var point = UnsafeUtility.AddressOf(ref section);
HashSet<string> res = new HashSet<string>();
FastEquality.AddExtraAOTTypes(typeof(SceneSection), res);
Debug.LogError($"SceneSection AddExtraAOTTypes {res}");
//GetHashCodeDelegate fn = (GetHashCodeDelegate)type_info_f.GetHashFn;
//Debug.LogError($"SceneSection FastEquality GetHashFn {fn.Method.Name}");
//var result = fn(ref section);
//Debug.LogError($"SceneSection GetHashFn {result}");
//CompareEqualDelegate efn = (CompareEqualDelegate)type_info_f.EqualFn;
//Debug.LogError($"SceneSection FastEquality EqualFn {efn.Method.Name}");
//var result_e = efn(ref section,ref section);
//Debug.LogError($"SceneSection EqualFn {result_e}");
var hascode = Unity.Entities.TypeManager.GetHashCode(section, index);
Debug.LogError($"SceneSection {section.SceneGUID} hascode {hascode}");
var hascode_fast = Unity.Entities.FastEquality.GetHashCode(section, type_info_f);
Debug.LogError($"SceneSection FastEquality GetHashCode {hascode_fast}");
}
......

and error happen on this line
Unity.Entities.TypeManager.GetHashCode(section, index);