Assertion failed: Start.IsValid()

unit23 · May 7, 2020, 5:06pm

What could possibly go wrong? Not using source code. Cross posting from Answers, since post is not showing up there on the stream. https://answers.unrealengine.com/que…rtisvalid.html

Crash Report


Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x1e2ff000

EPICA_Win64_DebugGame!TArray<unsigned int,TAlignedHeapAllocator<0> >::BulkSerialize()
EPICA_Win64_DebugGame!FRawStaticIndexBuffer16or32<unsigned int>::Serialize()
EPICA_Win64_DebugGame!FMultiSizeIndexContainer::Serialize()
EPICA_Win64_DebugGame!FSkeletalMeshLODRenderData::SerializeStreamedData()
EPICA_Win64_DebugGame!FSkeletalMeshStreamIn_IO::SerializeLODData()
EPICA_Win64_DebugGame!<lambda_3fb489b832b0a1dc9ff74a89f7ff1336>::operator()()
EPICA_Win64_DebugGame!TRenderAssetUpdate<FSkelMeshUpdateContext>::TickInternal()
EPICA_Win64_DebugGame!FAutoDeleteAsyncTask<FRenderAssetUpdate::FMipUpdateTask>::DoWork()
EPICA_Win64_DebugGame!FQueuedThread::Run()
EPICA_Win64_DebugGame!FRunnableThreadWin::Run()

VS


Exception thrown at 0x00007FFE945C12DE (vcruntime140.dll) in EPICA-Win64-DebugGame.exe: 0xC0000005: Access violation reading location 0x000001C41E2FF000.

--- d:\agent\_work\1\s\src\vctools\crt\vcruntime\src\string\amd64\memcpy.asm ---
00007FFE945C12D0 push rdi
00007FFE945C12D1 push rsi
00007FFE945C12D2 mov rax,r11
00007FFE945C12D5 mov rdi,rcx
00007FFE945C12D8 mov rcx,r8
00007FFE945C12DB mov rsi,r10
00007FFE945C12DE rep movs byte ptr [rdi],byte ptr [rsi]
00007FFE945C12E0 pop rsi
00007FFE945C12E1 pop rdi
00007FFE945C12E2 ret
--- No source file -------------------------------------------------------------
00007FFE945C12E3 int 3
00007FFE945C12E4 int 3
00007FFE945C12E5 int 3
00007FFE945C12E6 int 3
00007FFE945C12E7 int 3
00007FFE945C12E8 int 3
00007FFE945C12E9 nop dword ptr [rax]
--- d:\agent\_work\1\s\src\vctools\crt\vcruntime\src\string\amd64\memcpy.asm ---

LOG


[2020.05.07-16.49.29:284][899]LogUObjectHash: Compacting FUObjectHashTables data took 5.07ms
[2020.05.07-16.49.30:168][366]LogThreadingWindows: Error: Runnable thread PoolThread 10 crashed.
[2020.05.07-16.49.30:168][366]LogWindows: Error: === Critical error: ===
[2020.05.07-16.49.30:168][366]LogWindows: Error:
[2020.05.07-16.49.30:168][366]LogWindows: Error: Assertion failed: Start.IsValid() [File:D:/Build/++UE4/Sync/Engine/Source/Runtime/CoreUObject/Private/Serialization/BulkData.cpp] [Line: 1624]
[2020.05.07-16.49.30:168][366]LogWindows: Error:
[2020.05.07-16.49.30:168][366]LogWindows: Error:
[2020.05.07-16.49.30:168][366]LogWindows: Error:
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ffeac5ba799 KERNELBASE.dll!UnknownFunction ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64b1f8406 EPICA-Win64-DebugGame.exe!ReportAssert() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64b1fbd08 EPICA-Win64-DebugGame.exe!FWindowsErrorOutputDevice::Serialize() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64afd393d EPICA-Win64-DebugGame.exe!FOutputDevice::LogfImpl() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64af64147 EPICA-Win64-DebugGame.exe!FDebug::AssertFailed() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64af66600 EPICA-Win64-DebugGame.exe!FDebug::CheckVerifyFailedImpl() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64b2c8d9d EPICA-Win64-DebugGame.exe!FUntypedBulkData::CreateStreamingRequestForRange() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64df652dc EPICA-Win64-DebugGame.exe!FSkeletalMeshStreamIn_IO::SetIORequest() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64df2ffd6 EPICA-Win64-DebugGame.exe!<lambda_3fb489b832b0a1dc9ff74a89f7ff1336>::operator()() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64df6c4f9 EPICA-Win64-DebugGame.exe!TRenderAssetUpdate<FSkelMeshUpdateContext>::TickInternal() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64df41901 EPICA-Win64-DebugGame.exe!FAutoDeleteAsyncTask<FRenderAssetUpdate::FMipUpdateTask>::DoWork() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64aec880c EPICA-Win64-DebugGame.exe!FQueuedThread::Run() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64b20111f EPICA-Win64-DebugGame.exe!FRunnableThreadWin::Run() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ff64b200e14 EPICA-Win64-DebugGame.exe!FRunnableThreadWin::GuardedRun() ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ffeae907bd4 KERNEL32.DLL!UnknownFunction ]
[2020.05.07-16.49.30:168][366]LogWindows: Error: [Callstack] 0x00007ffeaecece51 ntdll.dll!UnknownFunction ]
[2020.05.07-16.49.30:168][366]LogWindows: Error:
[2020.05.07-16.49.30:168][366]LogWindows: Error: Crash in runnable thread PoolThread 10
[2020.05.07-16.49.30:285][427]LogExit: Executing StaticShutdownAfterError

unit23 · May 7, 2020, 8:51pm

Done some more digging, loaded build the project to launch the main map.


Error: Couldn't find file for package /Engine/EditorLandscapeResources/DataLayer requested by async loading code. NameToLoad: /Engine/EditorLandscapeResources/DataLayer

There is a file in UE_4_24/Engine/Content/EditorLandscapeResources/DataLayer.uasset, here has only 1kb in filesize which suggest it may be corrupted. However, while the file is currently not present in the current revision, it is in previous - under the saved/cooked folder, which is pretty weird since there were no noticeable crashes, log entries, during PIE or from packaging in the more recent build.

unit23 · May 14, 2020, 4:35pm

In case someone else getting this error, look at your project BP’s if filesize is around 2kb only, which suggest the file is corrupted.Unfortunately, was unable to resolve the error. The main issue was, corruption only became noticeable in packaged projects, DebugGame or VisualStudio attached process gave no concrete clue.

Things I tried also:

Delete DerivedDataCache file
Delete Saved/Immediate folder
Fixing almost all cooking warnings
Rebuild project
Upgrade from 4.24.3 to 4.25.0 (which yielded different errors)
Reinstalled UE4.24
Changes to the GameMode and LevelLoading, since that was among the things last worked on.
Various cooking settings, no Event Driven Loader, No AsyncLoading, just including a Blank Map

However, going back to the backup, and adding carefully updated content was a much faster solution. First copied mainly Static Meshes, then updated BP’s while also checking file size. During this process I noticed one file which was only 2kb in size, should have been much larger. So in the end it was likely that a corrupted file was the culprit.