Fortran で使う Makefile の書き方 (for GNU Make)

main.f90

program main
  use sub
  call helloworld
end program main

Makefile

FC = gfortran
TARGET = sample
OBJS = main.o sub.o

.SUFFIXES: .f90

%.o: %.f90
	$(COMPILE.f) $(OUTPUT_OPTION) $<

%.mod: %.f90 %.o
	@:

$(TARGET): $(OBJS)
	$(LINK.f) $^ $(LOADLIBES) $(LDLIBS) -o $@

main.o: sub.mod

sub.f90

module sub
  use, intrinsic :: iso_fortran_env
contains
  subroutine helloworld
    write(output_unit, '(*(g0))') 'Hello World!'
  end subroutine helloworld
end module sub