gfortran include directory with subroutines

Question

I have programmed some fortran subroutines. I saved the subroutines in a Desktop folder called subroutines. When I compile a fortran program, say main.f90 (located in a different folder than subroutines), that uses subroutines (e.g. sub1.f90, sub2.f90) of the folder subroutines, I need to copy every subroutine into the folder of main.f90 and then compile like this:

gfortran -o main main.f90 sub1.f90 sub2.f90

which outputs the executable file as desired.

My question is: Is there any compiler option in gfortran to include files from the subroutine folder without having to copy each subroutine to the folder of main.f90?

I have tried these two options:

gfortran -L/home/user/Desktop/subroutines -o main main.f90 sub1.f90 sub2.f90

gfortran -I/home/user/Desktop/subroutines -o main main.f90 sub1.f90 sub2.f90

both of these compiler options return the error: gfortran: No such file or directory

The only available fortran compiler in my PC is gfortran (no ifort).

You are almost certainly better off compiling each .f90 file separately and then linking finally. The -I flag relates to the search path for include files and module files. — francescalus
Youbare probably looking for some build system, such as make or some better modern alternative. — Vladimir F

arie64 arie64 · Accepted Answer · 2017-01-20T00:25:34

You can simply put the full path to the subroutine file. So you would augment your compilation as

gfortran -o main main.f90 subroutines/sub1.f90 subroutines/sub2.f90

or a clever way to do this call is to use expansions as so

gfortran -o main main.f90 subroutines/{sub1,sub2}.f90

where the curly brackets will expand to be the same as the first complication I show.

gfortran include directory with subroutines

1 Answers