GDC missing betterC switch

[vladislavp]

Hello, I am looking for help using betterC with GDC
(after this, my next step was to see if I can use wxWigdets with 
GDC betterC without
  wxD wrappers)

This question is essentially same as below from 2018( it did not 
have any answers).
https://forum.dlang.org/thread/usdqpbusosanlsugwbip@forum.dlang.org

If anyone would help with guidance on the above, very much 
appreciated.