For those who suffer from Visual Studio IntelliSense slowness

[Cultrarius]

@sparkie;435203

There is an easy way to automatically make the generated projects contain the /Yu flag for IntelliSense.

Inside the file VCProject.cs you can look for the following line: [FONT=Courier New]" <NMakeForcedUsingAssemblies>$(NMakeForcedUsingAssemblies)</NMakeForcedUsingAssemblies>" + ProjectFileGenerator.NewLine +
Once found, add this line below it: [FONT=Courier New]" <AdditionalOptions>/Yu</AdditionalOptions>" + ProjectFileGenerator.NewLine +

Now build the UnrealBuildTool and the next time you generate your project files, it will contain the flag for all the C++ projects inside the solution.

Awesome. This is really helpful, thank you!