I was looking at enforcing some standards on my application of many years standing (> 200,000 lines for fortran code) so did a trial build with Fortran 2003 (/stand:f03). 5000 warnings later....
It doesn't look like too big a job actually, after globally replacing a load of tabs with spaces and stuff like integer*n declarations with integer(n),
I few things are causing some head scratching:
1] integer data constants in HEX in some module declarations (example as below):
integer(4) :: Bright_Yellow =#00FFFF
integer(4) :: Dull_Blue =#800000