Crash seems inconsistent, doesn't seem to happen every time. You may have to change the variables and re-compile through the editor a few times to get it to trigger.
The crash did occur for me when editing a single cpp file, however it crashes more consistently when editing multiple cpp files and compiling.
Crash seems to occur regardless of whether the cpp files are saved in VS or not.
Result: Editor crashes
Expected: Compile completes successfully
ntdll!7ff9506b0000 + 9c034 KERNELBASE!7ff94e020000 + 1a34e UE4Editor-Core!ReportCrash(_EXCEPTION_POINTERS *) [WindowsPlatformCrashContext.cpp:1574] UE4Editor!7ff7bdaa0000 + 3b0ff VCRUNTIME140!7ff942e90000 + e3e0 ntdll!7ff9506b0000 + a130f ntdll!7ff9506b0000 + 4b5e4 ntdll!7ff9506b0000 + 9fe3e UE4Editor-CoreUObject!GetArchetypeFromRequiredInfoImpl(UClass const *,UObject const *,FName,EObjectFlags,bool) [UObjectArchetype.cpp:61] UE4Editor-CoreUObject!GetArchetypeFromRequiredInfoImpl(UClass const *,UObject const *,FName,EObjectFlags,bool) [UObjectArchetype.cpp:82] UE4Editor-CoreUObject!UObject::GetArchetype() [UObjectArchetype.cpp:207] UE4Editor-CoreUObject!UObject::IsBasedOnArchetype(UObject const * const) [UnrealType.h:6096] UE4Editor-CoreUObject!FObjectInstancingGraph::InstancePropertyValue(UObject *,UObject *,UObject *,bool,bool,bool) [CoreNative.cpp:286] UE4Editor-CoreUObject!FObjectPropertyBase::InstanceSubobjects(void *,void const *,UObject *,FObjectInstancingGraph *) [PropertyBaseObject.cpp:52] UE4Editor-CoreUObject!UStruct::InstanceSubobjectTemplates(void *,void const *,UStruct *,UObject *,FObjectInstancingGraph *) [Class.cpp:2155] UE4Editor-CoreUObject!FObjectInitializer::InstanceSubobjects(UClass *,bool,bool) [UObjectGlobals.cpp:2936] UE4Editor-CoreUObject!FObjectInitializer::PostConstructInit() [UObjectGlobals.cpp:2850] UE4Editor-CoreUObject!FObjectInitializer::~FObjectInitializer() [UObjectGlobals.cpp:2704] UE4Editor-CoreUObject!StaticConstructObject_Internal(FStaticConstructObjectParameters const &) [UObjectGlobals.cpp:3195] UE4Editor-Engine!UWorld::SpawnActor(UClass *,FTransform const *,FActorSpawnParameters const &) [LevelActor.cpp:508] UE4Editor-Engine!UWorld::SpawnActor(UClass *,FVector const *,FRotator const *,FActorSpawnParameters const &) [LevelActor.cpp:304] UE4Editor-UnrealEd!static void ReplaceActorHelper(class AActor *, class UClass *, class UObject * & const, class UClass *, class TMap<UObject *,UObject *,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<UObject *,UObject *,0> > & const, class TMap<UClass *,UClass *,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<UClass *,UClass *,0> > & const, class TMap<FSoftObjectPath,UObject *,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<FSoftObjectPath,UObject *,0> > & const, class TMap<UObject *,FActorAttachmentData,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<UObject *,FActorAttachmentData,0> > & const, class TArray<FActorReplacementHelper,TSizedDefaultAllocator<32> > & const, bool, bool & const) [KismetReinstanceUtilities.cpp:1832] UE4Editor-UnrealEd!FBlueprintCompileReinstancer::ReplaceInstancesOfClass_Inner(TMap<UClass *,UClass *,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<UClass *,UClass *,0> > &,UObject *,TSet<UObject *,DefaultKeyFuncs<UObject *,0>,FDefaultSetAllocator> *,bool,bool,bool,TSet<UObject *,DefaultKeyFuncs<UObject *,0>,FDefaultSetAllocator> const *,bool) [KismetReinstanceUtilities.cpp:2114] UE4Editor-UnrealEd!FBlueprintCompileReinstancer::BatchReplaceInstancesOfClass(TMap<UClass *,UClass *,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<UClass *,UClass *,0> > &,FBatchReplaceInstancesOfClassParameters const &) [KismetReinstanceUtilities.cpp:1517] UE4Editor-Kismet!FBlueprintCompilationManagerImpl::FlushReinstancingQueueImpl() [BlueprintCompilationManager.cpp:1638] UE4Editor-Kismet!FBlueprintCompilationManagerImpl::CompileSynchronouslyImpl(FBPCompileRequestInternal const &) [BlueprintCompilationManager.cpp:279] UE4Editor-Kismet!FBlueprintCompilationManager::CompileSynchronously(FBPCompileRequest const &) [BlueprintCompilationManager.cpp:3090] UE4Editor-UnrealEd!FBlueprintCompileReinstancer::CompileChildren() [KismetReinstanceUtilities.cpp:664] UE4Editor-UnrealEd!FBlueprintCompileReinstancer::ReinstanceObjects(bool) [KismetReinstanceUtilities.cpp:767] UE4Editor-HotReload!FHotReloadModule::ReinstanceClass(UClass *,UClass *,TMap<UClass *,UClass *,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<UClass *,UClass *,0> > const &) [HotReload.cpp:1258] UE4Editor-HotReload!FHotReloadModule::ReinstanceClasses() [HotReload.cpp:1244] UE4Editor-HotReload!TBaseRawMethodDelegateInstance<0,FHotReloadModule,void ,FDefaultDelegateUserPolicy>::ExecuteIfSafe() [DelegateInstancesImpl.h:469] UE4Editor-CoreUObject!UClassReplaceHotReloadClasses() [UObjectBase.cpp:842] UE4Editor-CoreUObject!ProcessNewlyLoadedUObjects(FName,bool) [UObjectBase.cpp:1002] UE4Editor-CoreUObject!TBaseStaticDelegateInstance<void ,FDefaultDelegateUserPolicy>::ExecuteIfSafe(FName,bool) [DelegateInstancesImpl.h:731] UE4Editor-Core!TMulticastDelegate<void ,FDefaultDelegateUserPolicy>::Broadcast(FName,bool) [DelegateSignatureImpl.inl:955] UE4Editor-Core!FModuleManager::LoadModuleWithFailureReason(FName,EModuleLoadResult &) [ModuleManager.cpp:508] UE4Editor-Core!FModuleManager::LoadModule(FName) [ModuleManager.cpp:342] UE4Editor-HotReload!FHotReloadModule::DoHotReloadInternal(TMap<FName,FString,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<FName,FString,0> > const &,TArray<UPackage *,TSizedDefaultAllocator<32> > const &,TArray<FName,TSizedDefaultAllocator<32> > const &,FOutputDevice &) [HotReload.cpp:799] UE4Editor-HotReload!static void UE4Function_Private::TFunctionRefCaller<<lambda_d85446a946c3f6776c68ebfeb93e5785>,void __cdecl(TMap<FName,FString,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<FName,FString,0> > const &,bool,enum ECompilationResult::Type) [Function.h:549] UE4Editor-HotReload!FHotReloadModule::CheckForFinishedModuleDLLCompile(EHotReloadFlags,bool &,bool &,FOutputDevice &,bool) [HotReload.cpp:1853] UE4Editor-HotReload!FHotReloadModule::Tick(float) [HotReload.cpp:1415] UE4Editor-Core!FTicker::Tick(float) [Ticker.cpp:95] UE4Editor!7ff7bdaa0000 + d03c UE4Editor!7ff7bdaa0000 + 2113c UE4Editor!7ff7bdaa0000 + 2121a UE4Editor!7ff7bdaa0000 + 3527d UE4Editor!7ff7bdaa0000 + 37faa KERNEL32!7ff950400000 + 17034 ntdll!7ff9506b0000 + 4d0d1
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