[solved] upgrade c++ project from ue 4.24 to 4.25 under Linux

I also had this same error, and it also indicated having to rebuild many SOs as well as the UE4Editor.

I applied the solution from sam.new but it wasn’t enough. I noticed that UBT is invoked by the editor on start up with:



/path/to/UE4/Engine/Binaries/DotNET/UnrealBuildTool.exe Development Linux -Project="/path/to/project/project.uproject" -TargetType=Editor -Progress -NoEngineChanges -NoHotReloadFromIDE


So, not having anything to lose, I removed the last two command line options as they looked like candidates contributing to the error message and re-invoked it with just:


/path/to/UE4/Engine/Binaries/DotNET/UnrealBuildTool.exe Development Linux -Project="/path/to/project/project.uproject" -TargetType=Editor -Progress

which solved the problem … and allowed me fix the errors causing the failure in the first palce

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