[Bug fortran/81615] save-temps and gfortran produces *.f90 files instead of *.i or *i90 files

[barrowes at alum dot mit.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81615

--- Comment #10 from Ben Barrowes <barrowes at alum dot mit.edu> ---
The reason the stdout redirection doesn't work for me is because I want to save
these preprocessed files during a "make" session. When I make, thousands of
fotran files are preprocessed and compiled. How do I save the stdout from each
one into its own directory?