[DCC Fatal Error] Program or unit 'Buttons' recursively uses itself
You cannot create a Delphi unit with the same name as is already in use. For example, do not create a buttons.pas unit for your application because the VCL already has a Buttons.pas unit.
The solution is to rename your unit.
To recreate this error, try to create a project called Buttons that uses a buttons.dpr project file.