The editor will crash on open after a hot reload if there are multiple modules in the project.
Regression:
No - behavior also occurs on 4.14.3 (CL 3249277)
Workaround:
Compiling with the editor closed (not preforming a hot reload) will clear hot reload dlls and allow the project to open normally
Result:
Project will fail to open with provided crash
Expected:
Editor launches since the code has been compiled since the last change.
LoginId:7156c35640f86204e61b8383f45dee17 EpicAccountId:e8c7fa630b6440f69a25a2c64d6c482c Assertion failed: GIsHotReload [File:D:\Build\++UE4+Release-4.15+Compile\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\UObjectBase.cpp] [Line: 594] Trying to recreate class 'Atps10Character' outside of hot reload! UE4Editor_UnrealEd!TObjectIterator<UObject>::operator++() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\coreuobject\public\uobject\uobjectiterator.h:298] UE4Editor_UnrealEd!PackageTools::GetFilteredPackageList() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\packagetools.cpp:86] UE4Editor_UnrealEd!PackageTools::CheckForReferencesToExternalPackages() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\packagetools.cpp:795] UE4Editor_UnrealEd!UEditorEngine::PackageUsingExternalObjects() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\playlevel.cpp:3694] UE4Editor_UnrealEd!UEditorEngine::Map_Check() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\editorserver.cpp:3981] UE4Editor_UnrealEd!UEditorEngine::HandleMapCommand() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\editorserver.cpp:6130] UE4Editor_UnrealEd!UEditorEngine::Exec() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\editorserver.cpp:5614] UE4Editor_UnrealEd!UUnrealEdEngine::Exec() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\unrealedsrv.cpp:670] UE4Editor_UnrealEd!FEditorFileUtils::LoadMap() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\filehelpers.cpp:2264] UE4Editor_UnrealEd!FEditorFileUtils::LoadDefaultMapAtStartup() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\filehelpers.cpp:3536] UE4Editor_UnrealEd!FUnrealEdMisc::OnInit() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\unrealedmisc.cpp:345] UE4Editor_UnrealEd!EditorInit() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\unrealed\private\unrealedglobals.cpp:97] UE4Editor!GuardedMain() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\launch.cpp:150] UE4Editor!GuardedMainWrapper() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:134] UE4Editor!WinMain() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:210] UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264] kernel32 ntdll
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-42041 in the post.