[CrashReport] UE4Editor_Engine!FMaterialShaderMap::GetMeshShaderMap() [materialshader.cpp:2395]

 2387       const FMeshMaterialShaderMap* FMaterialShaderMap::GetMeshShaderMap(FVertexFactoryType* VertexFactoryType) const
 2388       {
 2389       	checkSlow(bCompilationFinalized);
 2390       #if WITH_EDITOR 
 2391       	// Attempt to get some more info for a rare crash (UE-35937)
 2392       	checkf(OrderedMeshShaderMaps.Num() > 0 && bCompilationFinalized, TEXT("OrderedMeshShaderMaps.Num() is %d. bCompilationFinalized is %d. This may relate to bug UE-35937"), OrderedMeshShaderMaps.Num(), (int)bCompilationFinalized);
 2393       #endif
 2394 ***** 	const FMeshMaterialShaderMap* MeshShaderMap = OrderedMeshShaderMaps[VertexFactoryType->GetId()];
 2395       	checkSlow(!MeshShaderMap || MeshShaderMap->GetVertexFactoryType() == VertexFactoryType);
 2396       	return MeshShaderMap;
 2397       }

Assertion failed: OrderedMeshShaderMaps.Num() > 0 && bCompilationFinalized [File:D:\Build\++UE4+Release-4.19+Compile\Sync\Engine\Source\Runtime\Engine\Private\Materials\MaterialShader.cpp] [Line: 2393] OrderedMeshShaderMaps.Num() is -572662307. bCompilationFinalized is 0. This may relate to bug UE-35937

UE4Editor_Engine!FMaterialShaderMap::GetMeshShaderMap() [materialshader.cpp:2395]
UE4Editor_Engine!FMaterial::GetShaderPipeline() [materialshared.cpp:1936]
UE4Editor_Renderer!FDepthDrawingPolicy::FDepthDrawingPolicy() [depthrendering.cpp:314]
UE4Editor_Renderer!FDepthDrawingPolicyFactory::DrawMesh() [depthrendering.cpp:741]
UE4Editor_Renderer!FDeferredShadingSceneRenderer::RenderPrePassViewDynamic() [depthrendering.cpp:845]
UE4Editor_Renderer!FDeferredShadingSceneRenderer::RenderPrePassView() [depthrendering.cpp:982]
UE4Editor_Renderer!FDeferredShadingSceneRenderer::RenderPrePass() [depthrendering.cpp:1340]
UE4Editor_Renderer!FDeferredShadingSceneRenderer::Render() [deferredshadingrenderer.cpp:807]
UE4Editor_Renderer!RenderViewFamily_RenderThread() [scenerendering.cpp:2749]
UE4Editor_Renderer!TGraphTask<`FRendererModule::BeginRenderingViewFamily'::`33'::EURCMacro_FDrawSceneCommand>::ExecuteTask() [taskgraphinterfaces.h:829]
UE4Editor_Core!FNamedTaskThread::ProcessTasksNamedThread() [taskgraph.cpp:665]
UE4Editor_Core!FNamedTaskThread::ProcessTasksUntilQuit() [taskgraph.cpp:574]
UE4Editor_RenderCore!RenderingThreadMain() [renderingthread.cpp:331]
UE4Editor_RenderCore!FRenderingThread::Run() [renderingthread.cpp:465]
UE4Editor_Core!FRunnableThreadWin::Run() [windowsrunnablethread.cpp:76]