theemidee/ue4fastbuild

UE4FastBuild

This is a fixed version of the FASTBuild.cs file you can find here and here, for UE 4.20 and the windows SDK 10.

Please note also that only VS2017 is supported.

You will have to update a few other files from the UnrealBuildTool project, as stated here.

You will have to update the contents of the function AppendCLArguments_Global of the file VCToolChain.cs to be able to build with VS2017:

if(WindowsPlatform.bUseVCCompilerArgs && CompileEnvironment.bEnableUndefinedIdentifierWarnings)
{
    if (CompileEnvironment.bUndefinedIdentifierWarningsAsErrors)
    {
        if (Target.WindowsPlatform.Compiler == WindowsCompiler.VisualStudio2015 )
        {
            Arguments.Add("/we4668"); 
        }
        else if (Target.WindowsPlatform.Compiler == WindowsCompiler.VisualStudio2017)
        {
            Arguments.Add("/wd4668");
        }
    }
    else
    {
        Arguments.Add("/w44668");
    }
}

Do I have to compile the full source of UE4 to use FASTBuild?

Luckily no :)

All you need to do is:

• open the project file UnrealBuildTool.csproj in *UE_INSTALL_FOLDER}\Engine\Source\Programs\UnrealBuildTool*
• Add the FASTBuild.cs file
• Update the other files accordingly
• Build in Release: the project is pre-configured to output the binary in the correct folder
• Enjoy :)