Want to know how to Core\Misc\Build.h 's macro is determined? [Souce Code, Macro]

(Sorry for my poor English first of all.)
I want to know Misc\Build.h that all about containing UE4’s macros.
Build.h says it’s written in UBT, but I couldn’t find it.

Build configuration coming from UBT, do not modify
Like this.

I searched term UBT for the value written in Build.h, but I couldn’t find any clues.
If you help me, I owe you my life…
Thank you for reading it. :sob: :sob: