How do I compile only the UnrealBuildTool?

I made a change to the UnrealBuildTool in Linux now it won’t compile anything without giving the error shown below which is probably not revelant.

file changed: Engine/Source/Programs/UnrealBuildTool/Platform/Linux/LinuxToolChain.cs

How do I compile a single .cs file? I.,e. UnrealBuildTool.cs.

Building 193 actions with 12 processes...
[1/193] Compile SharedPCH.CoreUObject.ShadowErrors.h
clang++: error: argument unused during compilation: '-shared' [-Werror,-Wunused-command-line-argument]
[2/193] Compile SharedPCH.Core.ShadowErrors.TypeCastWarnings.h
clang++: error: argument unused during compilation: '-shared' [-Werror,-Wunused-command-line-argument]
[3/193] Compile PCH.CoreUObject.h