When running a multiplayer game, we have a random crash in what appears to be engine’s replication logic. Our setup uses a packaged (non-editor) build on two different machines over wired ethernet. At point of crash in UObjectPropertyBase::Identical line 45, ObjectA is not null but appears to be garbage. ObjectB looks fine. This happens when running exact same build copied to both machines. So far it seems to happen on game running as server. Do you know what would cause this or is there a workaround?
So far we have seen this in shipping and development builds but haven’t reproduced it in a debug build. We are running 4.4.0 built from source. Here is crash stack:
UObjectPropertyBase::Identical() 0x3f39653f + O bytes [File= c:\gamedev\Game\ue4\engine\source\runtime\coreuobject\private\uobject\propertybaseobject.cpp:45] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
FRepLayout::CompareProperties() 0x3f95745e + 311 bytes [File= c:\gamedev\Game\ue4\engine\source\runtime\engine\private\replayout.cpp:327] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
FRepLayout::ReplicateProperties() 0x3f96fca8 + 46 bytes [File= c:\gamedev\Game\ue4\engine\source\runtime\engine\private\replayout.cpp:531] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe] }
FObjectReplicator::ReplicateProperties() 0x3f841adf + O bytes [File= c:\gamedev\Game\ue4\engine\source\runtime\engine\private\datareplication.cpp:983] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
UActorChannel::ReplicateActor() 0x3f840b49 + O bytes [File= c:\gamedev\Game\ue4\engine\source\runtime\engine\private\datachannel.cpp:1809] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
UNetDriver::ServerReplicateActors() 0x3f92190f + 8 bytes [File= c:\gamedev\Game\ue4\engine\source\runtime\engine\private\networkdriver.cpp:2422] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
UNetDriver::TickFlush() 0x3f9243a1 + 15 bytes [File=c:\gamedev\Game\ue4\engine\source\runtime\engine\private\networkdriver.cpp:153] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
TBaseUObjectMethodDelegateInstance_OneParam::ExecuteIfSafe() 0x3f93965c + O bytes [File=c:\gamedev\Game\ue4\engine\source\runtime\core\public\delegates\delegateinstancesimpl.inl:532] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
TBaseMulticastDelegate_OneParam::Broadcast() 0x3f8e7975 + 14 bytes [File=c:\gamedev\Game\ue4\engine\source\runtime\core\public\delegates\delegatesignatureimpl.inl:1852] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
UWorld::Tick() 0x3f8fbddf + O bytes [File= c:\gamedev\Game\ue4\engine\source\runtime\engine\private\leveltick.cpp:1233] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
UGameEngine::Tick() 0x3f87e23c + O bytes [File=c:\gamedev\Game\ue4\engine\source\runtime\engine\private\gameengine.cpp:873] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
FEngineLoop::Tick() 0x3f25b13d + O bytes [File=c:\gamedev\Game\ue4\engine\source\runtime\launch\private\launchengineloop.cpp:2098] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
GuardedMain() 0x3f25725c + O bytes [File=c:\gamedev\Game\ue4\engine\source\runtime\launch\private\launch.cpp:133] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
GuardedMainWrapper() 0x3f2572aa + 5 bytes [File=c:\gamedev\Game\ue4\engine\source\runtime\launch\private\windows\launchwindows.cpp:125] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
WinMain() 0x3f25ba20 + 17 bytes [File=c:\gamedev\Game\ue4\engine\source\runtime\launch\private\windows\launchwindows.cpp:201] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
_tmainCRTStartup() 0x4047cd2d + 21 bytes [File=f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618] [in C:\gamedev\Game\GameRelease\WindowsNoEditor\Game\Binaries\Win64\Game-Win64-Shipping.exe]
Address = 0x76d459ed (filename not found) [in C:\Windows\system32\kernel32.dll]
Address = 0x76e7c541 (filename not found) [in C:\Wind0ws\SYSTEM32\ntdll.dll]
Address = 0x76e7c541 (filename not found) [in C:\Wind0ws\SYSTEM32\ntdll.dll]