While saving over an existing map the engine will crash if both maps have baked lighting.
RESULT
The engine crashes while attempting to save, with the following messaage in the log:
Fatal error: [Link Removed] [Line: 201] Renaming an object (Package /Temp/Untitled_5_BuiltData) on top of an existing object (Package /Game/_Base_BuiltData) is not allowed
EXPECTED
The current map is saved over the map in the content browser.
UE4Editor_CoreUObject!UObject::Rename() obj.cpp:201
UE4Editor_Engine!UWorld::Rename() world.cpp:507
UE4Editor_UnrealEd!SaveWorld() filehelpers.cpp:556
UE4Editor_UnrealEd!FEditorFileUtils::SaveMap() filehelpers.cpp:2311
UE4Editor_UnrealEd!InternalSavePackage() filehelpers.cpp:2705
UE4Editor_UnrealEd!FEditorFileUtils::PromptForCheckoutAndSave() filehelpers.cpp:3329
UE4Editor_UnrealEd!InternalSavePackages() filehelpers.cpp:2821
UE4Editor_UnrealEd!FEditorFileUtils::SaveDirtyPackages() filehelpers.cpp:3029
UE4Editor_MainFrame!FMainFrameActionCallbacks::SaveAll() mainframeactions.cpp:269
UE4Editor_MainFrame!TBaseStaticDelegateInstance<void __cdecl() delegateinstancesimpl.h:1027
UE4Editor_Slate!FUICommandList::ExecuteAction() uicommandlist.cpp:97
UE4Editor_Slate!SMenuEntryBlock::OnClicked() smenuentryblock.cpp:1041
UE4Editor_Slate!SMenuEntryBlock::OnMenuItemButtonClicked() smenuentryblock.cpp:1001
UE4Editor_Slate!TMemberFunctionCaller<SMenuEntryBlock,FReply() delegateinstanceinterface.h:165
UE4Editor_Slate!TTupleImpl<TIntegerSequence<unsigned int> >::ApplyAfter<TMemberFunctionCaller<SMenuEntryBlock,FReply() tuple.h:134
UE4Editor_Slate!TBaseSPMethodDelegateInstance<0,SMenuEntryBlock,0,FReply __cdecl() delegateinstancesimpl.h:327
UE4Editor_Slate!TBaseDelegate<FReply>::Execute() delegatesignatureimpl.inl:537
UE4Editor_Slate!SButton::OnMouseButtonUp() sbutton.cpp:278
UE4Editor_Slate!SMenuEntryButton::OnMouseButtonUp() smenuentryblock.cpp:399
UE4Editor_Slate!<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1>::operator() slateapplication.cpp:5075
UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1> >() slateapplication.cpp:238
UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() slateapplication.cpp:5064
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() slateapplication.cpp:5531
UE4Editor_Slate!FSlateApplication::OnMouseUp() slateapplication.cpp:5508
UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() windowsapplication.cpp:1698
UE4Editor_Core!FWindowsApplication::DeferMessage() windowsapplication.cpp:2120
UE4Editor_Core!FWindowsApplication::ProcessMessage() windowsapplication.cpp:867
UE4Editor_Core!FWindowsApplication::AppWndProc() windowsapplication.cpp:714
user32!<Unknown>
user32!<Unknown>
UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() windowsplatformmisc.cpp:980
UE4Editor!FEngineLoop::Tick() launchengineloop.cpp:2977
UE4Editor!GuardedMain() launch.cpp:166
UE4Editor!GuardedMainWrapper() launchwindows.cpp:134
UE4Editor!WinMain() launchwindows.cpp:210
UE4Editor!__scrt_common_main_seh() exe_common.inl:264
kernel32!<Unknown>
ntdll!<Unknown>
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