implicit none integer :: x, y x = 1 y = 0 ! include "timestwo.f90" ! double quote and inline comment check include "timestwo.f90" ! inline comment check if (x/=2) error stop 'failed on first include' ! leading space and single quote check include 'timestwo.f90' if (x/=4) error stop 'failed on second include' ! Most Fortran compilers can't handle the non-standard #include, ! including (ha!) Flang, Gfortran, Ifort and PGI. ! #include "timestwo.f90" print *, 'OK: Fortran include tests: x=',x end program