Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> I have marked these columns as unused in pg_class.h.
Keep your hands off 'em!
There are other purposes for system catalogs besides the internal
convenience of the backend, you know. "Unused at the moment by the
backend" does not mean "removable" --- you have no way to know what
user code you may break by removing such info.
regards, tom lane