There is nothing in the standard that specifies the suffix of the files. Intel always stated, that they treat *.f90
as the suffix for the free source format irrespective of the standard version. It is just a convention not based on any standard document.
Maybe the f90
suffix is little unfortunate, looking like just for Fortran 90, but you shouldn't hesitate to use it for every free-format source file.
Personally, I also do not like the practice of .f95
,.f03
, .f08
files. Should I rename the source file just because I call some intrinsic from a newer standard?