Hi, I’m trying to build my project with Cesium 5.1. I get the following error when trying to package my UE5 game: C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(192): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(962): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(970): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypesbase.h(447): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypesbase.h(472): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypesbase.h(489): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypes.h(85): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypes.h(94): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypes.h(100): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypes.h(106): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypes.h(112): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypes.h(118): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\wtypes.h(493): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidlbase.h(2275): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidlbase.h(2289): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidlbase.h(8492): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidlbase.h(8508): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(10444): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(11002): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(11034): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(11542): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(11557): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(12018): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(13832): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(13847): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(15586): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(15602): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(15749): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(15788): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(15805): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(15822): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(16067): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\objidl.h(16086): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\um\oaidl.h(571): error C2872: ‘byte’: ambiguous symbol C:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\shared\rpcndr.h(191): note: could be ‘unsigned char byte’ C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.34.31933\INCLUDE\cstddef(28): note: or ‘std::byte’ C:\Program Files\Epic Games\UE_5.1\Engine\Plugins\Marketplace\CesiumForUnreal\Source\ThirdParty\include\CesiumGltf\Material.h(26): error C2059: syntax error: ‘constant’ C:\Program Files\Epic Games\UE_5.1\Engine\Plugins\Marketplace\CesiumForUnreal\Source\ThirdParty\include\CesiumGltf\Material.h(26): error C2238: unexpected token(s) preceding ‘;’ C:\Program Files\Epic Games\UE_5.1\Engine\Plugins\Marketplace\CesiumForUnreal\Source\ThirdParty\include\CesiumGltf\Material.h(92): error C2589: ‘constant’: illegal token on right side of ‘::’ C:\Program Files\Epic Games\UE_5.1\Engine\Plugins\Marketplace\CesiumForUnreal\Source\ThirdParty\include\CesiumGltf\Material.h(92): error C2062: type ‘unknown-type’ unexpected Please advise. Thanks, suhair

See here: [image] Unable to Package UE5.0.3 project with Cesium v1.19.0 Cesium for Unreal Hi folks, I did some digging into this. Long story short, if you want to #include Cesium for Unreal headers in your own source files, you need to make sure those source files are built with these options (add them to your .Build.cs file): PublicDependencyModuleNames.AddRange(new string[] { "CesiumRuntime", "UMG" }); CppStandard = CppStandardVersion.Cpp17; bEnableExceptions = true; Here’s the explanation for each of these lines: PublicDependencyModuleNames.AddRange(new string[] { "CesiumRunti…

Thanks a lot! This fixed my issue.

Cesium 5.1 build error with UE5 packaged game

Cesium for Unreal

Kevin_Ring December 29, 2022, 10:18pm 2

See here:

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Cesium 5.1 build error with UE5 packaged game

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