simplify MPI test

test/fc_mpi/src/example.F90

@@ -1,27 +1,44 @@
 program example
 
-#if defined USE_MPI_MODULE
-   use mpi
-   implicit none
-#else
-   implicit none
+   call init()
+   call test_use()
+   call finalize()
+
+contains
+
+   subroutine init()
+      use mpi, only: MPI_Init
+      implicit none
+      integer :: ierr
+      call MPI_Init(ierr)
+   end subroutine
+
+   subroutine finalize()
+      use mpi, only: MPI_Finalize
+      implicit none
+      integer :: ierr
+      call MPI_Finalize(ierr)
+   end subroutine
+
+   subroutine test_use()
+
+      implicit none
 #include "mpif.h"
-#endif
 
-   integer :: ierr, rank, num_ranks
-   logical :: test_ok
+      integer :: ierr, rank, num_ranks
+      logical :: test_ok
 
-   call MPI_INIT(ierr)
-   call MPI_COMM_RANK(MPI_COMM_WORLD, rank, ierr)
-   call MPI_COMM_SIZE(MPI_COMM_WORLD, num_ranks, ierr)
-   call MPI_FINALIZE(ierr)
+      call MPI_COMM_RANK(MPI_COMM_WORLD, rank, ierr)
+      call MPI_COMM_SIZE(MPI_COMM_WORLD, num_ranks, ierr)
 
-   test_ok = (num_ranks == 2 .and. (rank == 0 .or. rank == 1))
+      test_ok = (num_ranks == 2 .and. (rank == 0 .or. rank == 1))
 
-   if (test_ok) then
-      if (rank == 0) print *, 'PASSED'
-   else
-      stop "FAILED"
-   endif
+      if (test_ok) then
+         if (rank == 0) print *, 'PASSED'
+      else
+         stop "FAILED"
+      endif
+
+   end subroutine
 
 end program