Compiling C++ in UE4 and then compile C++ code in Visual Studio causes UE4 to lock up

…Or something like that.

Here’s the Bug Report Info from the CrashReporter.exe:

MachineId:C3E91CEC443B1F1A68A4CF8050888240
EpicAccountId:9403e113212a4760bc6e1994823d8b40

Unknown exception - code 00000001 (first/second chance not available)

Fatal error: [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.7\Engine\Source\Runtime\CoreUObject\Private\UObject\Obj.cpp] [Line: 115] 
Renaming an object (GetDebtWheelFront //Engine//Transient.GetDebtWheelFront_13) on top of an existing obj

KERNELBASE + 35740 bytes
UE4Editor_Core!FOutputDeviceWindowsError::Serialize() + 292 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\private\windows\windowsplatformoutputdevices.cpp:95]
UE4Editor_Core!FMsg::Logf__VA() + 463 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\private\misc\outputdevice.cpp:526]
UE4Editor_CoreUObject!UObject::Rename() + 791 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\coreuobject\private\uobject\obj.cpp:115]
UE4Editor_GetDebt_8312!AGetDebtGameMode::AGetDebtGameMode() + 145 bytes [c:\users\tom_m_000\documents\unreal projects\get-debt\source\getdebt\getdebtgamemode.cpp:18]
UE4Editor_HotReload!FHotReloadClassReinstancer::ReconstructClassDefaultObject() + 309 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\developer\hotreload\private\hotreloadclassreinstancer.cpp:215]
UE4Editor_HotReload!FHotReloadClassReinstancer::RecreateCDOAndSetupOldClassReinstancing() + 122 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\developer\hotreload\private\hotreloadclassreinstancer.cpp:236]
UE4Editor_HotReload!FHotReloadClassReinstancer::FHotReloadClassReinstancer() + 240 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\developer\hotreload\private\hotreloadclassreinstancer.cpp:273]
UE4Editor_HotReload!FHotReloadModule::ReinstanceClass() + 82 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\developer\hotreload\private\hotreload.cpp:845]
UE4Editor_CoreUObject!UClassReplaceHotReloadClasses() + 307 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\coreuobject\private\uobject\uobjectbase.cpp:703]
UE4Editor_CoreUObject!TBaseStaticDelegateInstance<void __cdecl(void)>::ExecuteIfSafe() + 7 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\public\delegates\delegateinstancesimpl_variadics.inl:921]
UE4Editor_Core!TBaseMulticastDelegate<void>::Broadcast() + 149 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\public\delegates\delegatesignatureimpl_variadics.inl:1030]
UE4Editor_Core!FModuleManager::LoadModuleWithFailureReason() + 2194 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\private\modules\modulemanager.cpp:359]
UE4Editor_Core!FModuleManager::LoadModule() + 56 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\private\modules\modulemanager.cpp:238]
UE4Editor_HotReload!FHotReloadModule::DoHotReloadInternal() + 648 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\developer\hotreload\private\hotreload.cpp:654]
UE4Editor_HotReload!FHotReloadModule::DoHotReloadFromIDE() + 1660 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\developer\hotreload\private\hotreload.cpp:1059]
UE4Editor_HotReload!FHotReloadModule::Tick() + 112 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\developer\hotreload\private\hotreload.cpp:995]
UE4Editor!FTicker::Tick() + 698 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\public\containers\ticker.h:90]
UE4Editor!FEngineLoop::Tick() + 6356 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\launch\private\launchengineloop.cpp:2352]
UE4Editor!GuardedMain() + 1404 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\launch\private\launch.cpp:142]
UE4Editor!GuardedMainWrapper() + 26 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() + 249 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\launch\private\windows\launchwindows.cpp:202]
UE4Editor!__tmainCRTStartup() + 329 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]

Hey asperatology-

Could you provide some additional information to help us investigate this crash? Were you attempting to compile inside the editor and Visual Studio at the same time? Had you changed anything in code / the editor between compile attempts? Can you reproduce the crash in a new code project with no additional content? Additionally, could you also provide the log file from the crash?

Cheers

I tried for a bit while on reproducing the results. It seems it magically fixed itself.

However, the crash you experienced here is related to this. Because at the time, I was switching back and forth numerous times while doing compilation builds trying to understand what my part of the code is wrong, when it happened.

Hey asperatology-

I’m glad to hear that this issue is no longer affecting you. When compiling code (in VS or in the editor) I would suggest not attempting to change anything in Visual Studio or the editor (or closing either program) while the process is running. I will be marking this post as resolved for tracking purposes, however feel free to reopen it if this bug reappears.

Cheers