I was trying to build lightmap for a relatively small scene and the errored occured right after the scene data finished exporting:
23:17:31: === Critical error: ===
23:17:31:
23:17:31: Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Containers\Array.h] [Line: 691]
23:17:31: Array index out of bounds: 2742 from an array of size 2742
23:17:31:
23:17:31:
23:17:31:
23:17:31:
23:17:31: 0x00007ff6f47c2dac UnrealLightmass.exe!Lightmass::FStaticMeshStaticLightingMesh::GetTriangleIndices() []
23:17:31:
23:17:31: 0x00007ff6f473b05a UnrealLightmass.exe!Lightmass::FEmbreeGeometry::FEmbreeGeometry() []
23:17:31:
23:17:31: 0x00007ff6f4744f55 UnrealLightmass.exe!Lightmass::FEmbreeAggregateMesh::AddMesh() []
23:17:31:
23:17:31: 0x00007ff6f479421e UnrealLightmass.exe!Lightmass::FStaticLightingSystem::FStaticLightingSystem() []
23:17:31:
23:17:31: 0x00007ff6f47498b1 UnrealLightmass.exe!Lightmass::BuildStaticLighting() []
23:17:31:
23:17:31: 0x00007ff6f476cda1 UnrealLightmass.exe!Lightmass::LightmassMain() []
23:17:31:
23:17:31: 0x00007ff6f478cf97 UnrealLightmass.exe!main() []
23:17:31:
23:17:31: 0x00007ff6f47f5ebc UnrealLightmass.exe!__scrt_common_main_seh() []
23:17:31:
23:17:31: 0x00007ffccf5b244d KERNEL32.DLL!UnknownFunction []
23:17:31:
23:17:31: 0x00007ffcd06adf78 ntdll.dll!UnknownFunction []
by the way I’ve tried to clean and validate cache in swarm but it didn’t work
however, GPU lightmass was fine for this scene, anyone having any clue how to solve this?