UE4.27.2 Dangling reference and assertion failure in FMaterialShader::GetShaderBindings() in ShaderBaseClasses.cpp

This seems to be a threading issue, as forcing the editor to run single threaded with -onethread makes the assert not reproduce.

UDN [Link Removed]

UE4Editor-Renderer.dll!FMaterialShader::GetShaderBindings()

  UE4Editor-Renderer.dll!FMeshMaterialShader::GetShaderBindings()

  [Inline Frame] UE4Editor-Renderer.dll!TBasePassVertexShaderPolicyParamType<FUniformLightMapPolicy>::GetShaderBindings()

  UE4Editor-Renderer.dll!FMeshPassProcessor::BuildMeshDrawCommands()

  UE4Editor-Renderer.dll!FBasePassMeshProcessor::Process()

  UE4Editor-Renderer.dll!FBasePassMeshProcessor::TryAddMeshBatch()

  UE4Editor-Renderer.dll!FBasePassMeshProcessor::AddMeshBatch()

  UE4Editor-Renderer.dll!FPrimitiveSceneInfo::CacheMeshDrawCommands::__l2::<lambda>(int Index)

  [Inline Frame] UE4Editor-Renderer.dll!Invoke()

  [Inline Frame] UE4Editor-Renderer.dll!UE4Function_Private::TFunctionRefCaller<void <lambda>(int),void __cdecl(int)>::Call(void *)

  [Inline Frame] UE4Editor-Renderer.dll!UE4Function_Private::TFunctionRefBase<UE4Function_Private::FFunctionRefStoragePolicy,void __cdecl(int)>::operator()(int <Params_0>)

  UE4Editor-Renderer.dll!ParallelForImpl::TParallelForData<void <lambda>(int)>::Process()

  [Inline Frame] UE4Editor-Renderer.dll!ParallelForImpl::TParallelForTask<void <lambda>(int)>::DoTask()

  UE4Editor-Renderer.dll!TGraphTask<ParallelForImpl::TParallelForTask<void <lambda>(int)>>::ExecuteTask()

  [Inline Frame] UE4Editor-Core.dll!FBaseGraphTask::Execute()

  UE4Editor-Core.dll!FTaskThreadAnyThread::ProcessTasks()

  UE4Editor-Core.dll!FTaskThreadAnyThread::ProcessTasksUntilQuit()

  [Inline Frame] UE4Editor-Core.dll!FTaskThreadBase::Run()

  UE4Editor-Core.dll!FTaskThreadAnyThread::Run()

  UE4Editor-Core.dll!FRunnableThreadWin::Run()

  UE4Editor-Core.dll!FRunnableThreadWin::GuardedRun()