Difficulties with enabling fortran interface

[AtticusBeachy]

Installation works perfectly when I configure using
./configure --prefix=/usr/local/zoltan

However, when I run

./configure --prefix=/usr/local/zoltan --enable-f90interface
make everything

It crashes with the following series of errors

make[3]: Entering directory '/home/crow/Downloads/Zoltan-3.901/BuildDir/src/fdriver'
/usr/local/bin/mpif90 -I ../ -I . -g -O2  -c -o mpi_h.o `test -f '../../../src/fdriver/mpi_h.f' || echo '../../../src/fdriver/'`../../../src/fdriver/mpi_h.f
/usr/local/bin/mpif90 -I ../ -I . -g -O2  -c -o farg_typical.o `test -f '../../../src/fdriver/farg_typical.f' || echo '../../../src/fdriver/'`../../../src/fdriver/farg_typical.f
/usr/local/bin/mpif90 -I ../ -I . -g -O2  -c -o mmio.o `test -f '../../../src/fdriver/mmio.f' || echo '../../../src/fdriver/'`../../../src/fdriver/mmio.f
/usr/local/bin/mpif90  -I ../ -I . -g -O2 -c -o fdr_sort.o  `test -f '../../../src/fdriver/fdr_sort.f90' || echo '../../../src/fdriver/'`../../../src/fdriver/fdr_sort.f90
/usr/local/bin/mpif90  -I ../ -I . -g -O2 -c -o fdr_const.o  `test -f '../../../src/fdriver/fdr_const.f90' || echo '../../../src/fdriver/'`../../../src/fdriver/fdr_const.f90
/usr/local/bin/mpif90  -I ../ -I . -g -O2 -c -o fdr_input.o  `test -f '../../../src/fdriver/fdr_input.f90' || echo '../../../src/fdriver/'`../../../src/fdriver/fdr_input.f90
../../../src/fdriver/fdr_input.f90:424:17:

  413 |   call MPI_Bcast(Test_Multi_Callbacks, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)
      |                 2
......
  424 |   call MPI_Bcast(pio_info%pdsk_root, len(pio_info%pdsk_root), MPI_CHARACTER, &
      |                 1
Error: Type mismatch between actual argument at (1) and actual argument at (2) (CHARACTER(1025)/INTEGER(4)).
../../../src/fdriver/fdr_input.f90:426:17:

  413 |   call MPI_Bcast(Test_Multi_Callbacks, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)
      |                 2
......
  426 |   call MPI_Bcast(pio_info%pdsk_subdir, len(pio_info%pdsk_root), MPI_CHARACTER, &
      |                 1
Error: Type mismatch between actual argument at (1) and actual argument at (2) (CHARACTER(1025)/INTEGER(4)).
../../../src/fdriver/fdr_input.f90:428:17:

  413 |   call MPI_Bcast(Test_Multi_Callbacks, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)
      |                 2
......
  428 |   call MPI_Bcast(pio_info%pexo_fname, len(pio_info%pdsk_root), MPI_CHARACTER, &
      |                 1
Error: Type mismatch between actual argument at (1) and actual argument at (2) (CHARACTER(1025)/INTEGER(4)).
../../../src/fdriver/fdr_input.f90:436:19:

  413 |   call MPI_Bcast(Test_Multi_Callbacks, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)
      |                 2  
......
  436 |     call MPI_Bcast(pio_info%dsk_list, pio_info%dsk_list_cnt, MPI_INTEGER, &
      |                   1
Error: Rank mismatch between actual argument at (1) and actual argument at (2) (scalar and rank-1)
../../../src/fdriver/fdr_input.f90:441:17:

  413 |   call MPI_Bcast(Test_Multi_Callbacks, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)
      |                 2
......
  441 |   call MPI_Bcast(prob%ztnPrm_file, len(prob%ztnPrm_file), MPI_CHARACTER, &
      |                 1
Error: Type mismatch between actual argument at (1) and actual argument at (2) (CHARACTER(1024)/INTEGER(4)).
../../../src/fdriver/fdr_input.f90:445:17:

  413 |   call MPI_Bcast(Test_Multi_Callbacks, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)
      |                 2
......
  445 |   call MPI_Bcast(prob%method, len(prob%method), MPI_CHARACTER, 0,MPI_COMM_WORLD,ierr)
      |                 1
Error: Type mismatch between actual argument at (1) and actual argument at (2) (CHARACTER(32)/INTEGER(4)).
../../../src/fdriver/fdr_input.f90:453:21:

  413 |   call MPI_Bcast(Test_Multi_Callbacks, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)
      |                 2    
......
  453 |       call MPI_Bcast(prob%params(i)%str(0), size, MPI_CHARACTER, 0, &
      |                     1
Error: Type mismatch between actual argument at (1) and actual argument at (2) (CHARACTER(128)/INTEGER(4)).
../../../src/fdriver/fdr_input.f90:455:21:

  413 |   call MPI_Bcast(Test_Multi_Callbacks, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)
      |                 2    
......
  455 |       call MPI_Bcast(prob%params(i)%str(1), size, MPI_CHARACTER, 0, &
      |                     1
Error: Type mismatch between actual argument at (1) and actual argument at (2) (CHARACTER(128)/INTEGER(4)).
make[3]: *** [Makefile:403: fdr_input.o] Error 1
make[3]: Leaving directory '/home/crow/Downloads/Zoltan-3.901/BuildDir/src/fdriver'
make[2]: *** [Makefile:3536: all-recursive] Error 1
make[2]: Leaving directory '/home/crow/Downloads/Zoltan-3.901/BuildDir/src'
make[1]: *** [Makefile:534: all-recursive] Error 1
make[1]: Leaving directory '/home/crow/Downloads/Zoltan-3.901/BuildDir'
make: *** [Makefile:1022: everything] Error 2

I am using gfortran, which is not one of the compilers mentioned in the Known_Problems text file.
Operating System: Linux Mint 21

[AtticusBeachy]

I figured out the problem. The GFortran compiler enforces type matching for version 10 and later, which causes Zoltan to crash. This can be fixed by using version 9 or earlier.

In Linux Mint, the current version of GFortran can be uninstalled and version 9 installed using the following terminal commands:

sudo apt purge gfortran
sudo apt install gfortran-9 

I strongly recommend adding this information to the documentation.

[adigitoleo]

Using -fallow-argument-mismatch I was able to compile the code with gfortran 12.2, in fact I can't understand where the mismatch comes from because I can only see the arguments passed to MPI_Bcast being declared as integers everywhere, so I don't follow where the CHARACTER type is coming from, taking Test_Multi_Callbacks for example:

src/fdriver/fdr_migrate.f90
170:  if (Test_Multi_Callbacks.eq.1) then

src/fdriver/fdr_loadbal.f90
253:  if (Test_Multi_Callbacks .eq. 1)  then
283:    if (Test_Multi_Callbacks.eq.1) then
298:  if (Test_Multi_Callbacks.eq.1) then
317:    if (Test_Multi_Callbacks .eq. 1)  then
378:  if (Test_Multi_Callbacks .eq. 1) then

src/fdriver/fdr_input.f90
255:        Test_Multi_Callbacks = iachar(trim(inp_line(index(inp_line,"= ")+2:))) - iachar('0')
413:  call MPI_Bcast(Test_Multi_Callbacks, 1, MPI_INTEGER, 0, MPI_COMM_WORLD, ierr)

src/fdriver/fdr_const.f90
63:public :: Test_Multi_Callbacks
80:integer(Zoltan_INT) :: Test_Multi_Callbacks = 0

Maybe the iachar can return a CHARACTER somehow? Fortran docs are not super clear to me. Perhaps someone who understands fortran could take a look. There are some related discussions in other projects where people have suggested replacing #include 'mpif.h' statements with use mpi, see e.g. NOAA-GFDL/FMS#561

[AtticusBeachy]

I eventually figured this out as well. I configured using the command:

./configure --prefix=/usr/local/zoltan --enable-mpi --with-mpi-compilers --enable-f90interface --with-gnumake FCFLAGS="-w -fallow-argument-mismatch -O2" FFLAGS="-w -fallow-argument-mismatch -O2"

The iachar function returns an integer type according to the Fortran documentation:

Description:
IACHAR(C) returns the code for the ASCII character in the first character position of C.
Syntax:
RESULT = IACHAR(C [, KIND])
Return value:
The return value is of type INTEGER and of kind KIND. If KIND is absent, the return value is of default integer kind.

The type mismatch is a very confusing error.