I have a question for gcc front-end

[Zack Weinberg]

There is no option that does what you want.  This is a deliberate,
albeit controversial, design decision which we are not presently
interested in debating.

If you are writing a back end, consider using the existing, well-
understood machinery for porting GCC to a new architecture.  If you go
that route you can get plenty of help from this list.  If you insist
on splitting the compiler at a different point you are on your own.

zw