Use mpi module instead of mpif header file.

configure.ac

@@ -426,7 +426,9 @@ fi
 # Checks for header files.
 
 if test "$want_mpi" = yes; then
-    CIT_FC_MPI_HEADER([$MPIFC], [$FLAGS_CHECK])
+    CIT_FC_MPI_MODULE([mpif.h], [$MPIFC], [$FLAGS_CHECK], [], [
+        AC_MSG_FAILURE([cannot compile a trivial MPI program using $MPIFC])
+    ])
 fi
 
 # Checks for typedefs, structures, and compiler characteristics.

m4/cit_fortran.m4

@@ -149,11 +149,14 @@ AC_LANG_POP(Fortran)
 ])dnl CIT_FC_STREAM_IO
 
 
-# CIT_FC_MPI_MODULE(FILENAME, MPIFC, MPIFCFLAGS)
+# CIT_FC_MPI_MODULE(FILENAME, MPIFC, MPIFCFLAGS,
+#                   [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
 # -----------------------------------------------------
 AC_DEFUN([CIT_FC_MPI_MODULE], [
-# Use 'mpi' module or 'mpif.h', as appropriate.  UNFINISHED.  This
-# strategy doesn't play well with "implicit none": whether the
+# Use 'mpi' module or 'mpif.h', as appropriate.  UNFINISHED.
+# The default actions are to create FILENAME that either uses the
+# appropriate module or includes the existing mpif.h.
+# This strategy doesn't play well with "implicit none": whether the
 # generated header must be included before or after "implicit none"
 # depends upon the result of the test!  It might be possible to make
 # "use mpi" always work: simply generate an 'mpi' module if the MPI
@@ -166,6 +169,7 @@ cfgfile="${ofile}T"
 trap "rm \"$cfgfile\"; exit 1" 1 2 15
 rm -f "$cfgfile"
 
+cit_fc_header=none
 cit_fc_save_fc=$FC
 cit_fc_save_fcflags=$FCFLAGS
 FC=$2
@@ -181,9 +185,10 @@ AC_COMPILE_IFELSE([
 ]])
 ], [
     AC_MSG_RESULT(yes)
-    cit_fc_header="use mpi"
+    m4_default([$4], [cit_fc_header="use mpi"])
 ], [
     AC_MSG_RESULT(no)
+    m4_default([$5], [
     AC_MSG_CHECKING([whether mpif.h works])
     AC_COMPILE_IFELSE([
         AC_LANG_PROGRAM([], [[
@@ -206,7 +211,7 @@ dnl to override the system header.
         AC_MSG_RESULT(no)
         AC_MSG_FAILURE([cannot compile a trivial MPI program using $2])
     ])
-])
+])])
 
 if test "$cit_fc_header" != "none"; then
     AC_MSG_NOTICE([creating $ofile])

src/specfem2D/assemble_MPI.F90

@@ -65,10 +65,11 @@ subroutine assemble_MPI_scalar(array_val1,npoin_val1, &
                               nibool_interfaces_acoustic,nibool_interfaces_elastic, &
                               nibool_interfaces_poroelastic,my_neighbours)
 
+  use :: mpi
+
   implicit none
 
   include 'constants.h'
-  include 'mpif.h'
 
   integer, intent(in)  :: ninterface
   integer, intent(in)  :: max_interface_size
@@ -229,10 +230,11 @@ subroutine assemble_MPI_vector_ac(array_val1,npoin, &
                                  buffer_recv_faces_vector_ac, &
                                  my_neighbours )
 
+  use :: mpi
+
   implicit none
 
   include 'constants.h'
-  include 'mpif.h'
   include 'precision.h'
 
   integer, intent(in)  :: npoin
@@ -358,10 +360,11 @@ subroutine assemble_MPI_vector_el(array_val2,npoin, &
                                    buffer_recv_faces_vector_el, &
                                    my_neighbours)
 
+  use :: mpi
+
   implicit none
 
   include 'constants.h'
-  include 'mpif.h'
   include 'precision.h'
 
   integer, intent(in)  :: npoin
@@ -465,10 +468,11 @@ subroutine assemble_MPI_vector_po(array_val3,array_val4,npoin, &
                            buffer_recv_faces_vector_pos,buffer_recv_faces_vector_pow, &
                            my_neighbours)
 
+  use :: mpi
+
   implicit none
 
   include 'constants.h'
-  include 'mpif.h'
   include 'precision.h'
 
   integer, intent(in)  :: npoin

src/specfem2D/check_stability.F90

@@ -53,11 +53,11 @@ subroutine check_stability(myrank,time,it,NSTEP,NOISE_TOMOGRAPHY, &
 
 ! checks simulation stability and outputs timerun infos
 
-  implicit none
-  include "constants.h"
 #ifdef USE_MPI
-  include "mpif.h"
+  use :: mpi
 #endif
+  implicit none
+  include "constants.h"
 
   integer :: myrank,it,NSTEP,NOISE_TOMOGRAPHY
 

src/specfem2D/checkgrid.F90

@@ -54,12 +54,13 @@ subroutine checkgrid(vpext,vsext,rhoext,density,poroelastcoef, &
 
 ! check the mesh, stability and number of points per wavelength
 
+#ifdef USE_MPI
+  use :: mpi
+#endif
+
   implicit none
 
   include "constants.h"
-#ifdef USE_MPI
-  include 'mpif.h'
-#endif
 
 ! option to display only part of the mesh and not the whole mesh,
 ! for instance to analyze Cuthill-McKee mesh partitioning etc.

src/specfem2D/exit_mpi.F90

@@ -46,11 +46,11 @@
 !-----------------------------------------------
 subroutine exit_MPI(error_msg)
 
-  implicit none
 #ifdef USE_MPI
   ! standard include of the MPI library
-  include "mpif.h"
+  use :: mpi
 #endif
+  implicit none
 
   ! identifier for error message file
   integer, parameter :: IERROR = 30

src/specfem2D/get_MPI.F90

@@ -59,10 +59,11 @@ subroutine get_MPI(nspec,ibool,knods,ngnod,nglob,elastic,poroelastic, &
 
 ! sets up the MPI interface for communication between partitions
 
+  use :: mpi
+
   implicit none
 
   include "constants.h"
-  include 'mpif.h'
 
   integer, intent(in)  :: nspec, nglob, ngnod
   logical, dimension(nspec), intent(in)  :: elastic, poroelastic

src/specfem2D/initialize_simulation.F90

@@ -47,11 +47,11 @@
   subroutine initialize_simulation(nproc,myrank,NUMBER_OF_PASSES, &
                   ninterface_acoustic,ninterface_elastic,ninterface_poroelastic)
 
-  implicit none
-  include "constants.h"
 #ifdef USE_MPI
-  include "mpif.h"
+  use :: mpi
 #endif
+  implicit none
+  include "constants.h"
 
   integer :: nproc,myrank,NUMBER_OF_PASSES
   integer :: ninterface_acoustic, ninterface_elastic,ninterface_poroelastic

src/specfem2D/locate_receivers.F90

@@ -54,12 +54,13 @@ subroutine locate_receivers(ibool,coord,nspec,nglob,xigll,zigll, &
                           coorg,knods,ngnod,npgeo,ipass, &
                           x_final_receiver, z_final_receiver)
 
+#ifdef USE_MPI
+  use :: mpi
+#endif
+
   implicit none
 
   include "constants.h"
-#ifdef USE_MPI
-  include "mpif.h"
-#endif
 
   integer nrec,nspec,nglob,ngnod,npgeo,ipass
   integer, intent(in)  :: nproc, myrank

src/specfem2D/locate_source_force.F90

@@ -50,12 +50,13 @@ subroutine locate_source_force(ibool,coord,nspec,nglob,xigll,zigll,x_source,z_so
                ispec_selected_source,is_proc_source,nb_proc_source,nproc,myrank, &
                xi_source,gamma_source,coorg,knods,ngnod,npgeo,ipass,iglob_source)
 
+#ifdef USE_MPI
+  use :: mpi
+#endif
+
   implicit none
 
   include "constants.h"
-#ifdef USE_MPI
-  include "mpif.h"
-#endif
 
   integer nspec,nglob,ngnod,npgeo,ipass
 

src/specfem2D/locate_source_moment_tensor.F90

@@ -51,12 +51,13 @@ subroutine locate_source_moment_tensor(ibool,coord,nspec,nglob, &
                ispec_selected_source,is_proc_source,nb_proc_source,nproc,myrank, &
                xi_source,gamma_source,coorg,knods,ngnod,npgeo,ipass)
 
+#ifdef USE_MPI
+  use :: mpi
+#endif
+
   implicit none
 
   include "constants.h"
-#ifdef USE_MPI
-  include "mpif.h"
-#endif
 
   integer nspec,nglob,ngnod,npgeo,ipass
 

src/specfem2D/plotpost.F90

@@ -80,12 +80,13 @@ subroutine plotpost(displ,coord,vpext,x_source,z_source,st_xval,st_zval,it,dt,co
 ! PostScript display routine
 !
 
+#ifdef USE_MPI
+  use :: mpi
+#endif
+
   implicit none
 
   include "constants.h"
-#ifdef USE_MPI
-  include 'mpif.h'
-#endif
 
 ! color palette
   integer, parameter :: NUM_COLORS = 236

src/specfem2D/pml_init.F90

@@ -47,13 +47,13 @@ subroutine pml_init(nspec,nglob,anyabs,ibool,nelemabs,codeabs,numabs,&
                     read_external_mesh,region_CPML,&
                     SIMULATION_TYPE,PML_interior_interface,nglob_interface,SAVE_FORWARD,myrank,mask_ibool)
 
-  implicit none
-  include 'constants.h'
-
 #ifdef USE_MPI
-  include 'mpif.h'
+  use :: mpi
 #endif
 
+  implicit none
+  include 'constants.h'
+
   integer :: SIMULATION_TYPE,nglob_interface,myrank
 
   integer :: nspec,nglob,nelemabs,nspec_PML,NELEM_PML_THICKNESS

src/specfem2D/prepare_color_image.F90

@@ -49,11 +49,11 @@ subroutine prepare_color_image_init(NX_IMAGE_color,NZ_IMAGE_color, &
                             zmin_color_image,zmax_color_image, &
                             coord,nglob,npgeo,factor_subsample_image)
 
-  implicit none
-  include "constants.h"
 #ifdef USE_MPI
-  include "mpif.h"
+  use :: mpi
 #endif
+  implicit none
+  include "constants.h"
 
   integer :: NX_IMAGE_color,NZ_IMAGE_color
 
@@ -297,11 +297,11 @@ subroutine prepare_color_image_vp(nglob,image_color_vp_display,iglob_image_color
 
 ! stores P-velocity model in image_color_vp_display
 
-  implicit none
-  include "constants.h"
 #ifdef USE_MPI
-  include "mpif.h"
+  use :: mpi
 #endif
+  implicit none
+  include "constants.h"
 
   integer :: nglob,nspec
   integer :: NX_IMAGE_color,NZ_IMAGE_color

src/specfem2D/prepare_initialfield.F90

@@ -51,11 +51,11 @@ subroutine prepare_initialfield(myrank,any_acoustic,any_poroelastic,over_critica
                         A_plane, B_plane, C_plane, &
                         accel_elastic,veloc_elastic,displ_elastic)
 
-  implicit none
-  include "constants.h"
 #ifdef USE_MPI
-  include "mpif.h"
+  use :: mpi
 #endif
+  implicit none
+  include "constants.h"
 
   integer :: myrank
   logical :: any_acoustic,any_poroelastic

src/specfem2D/read_databases.F90

@@ -687,13 +687,13 @@ subroutine read_databases_absorbing(myrank,ipass,nelemabs,nspec,anyabs, &
 
 ! reads in absorbing edges
 
-  implicit none
-  include "constants.h"
-
 #ifdef USE_MPI
-  include 'mpif.h'
+  use :: mpi
 #endif
 
+  implicit none
+  include "constants.h"
+
   integer :: myrank,ipass,nspec
   integer :: nelemabs
   integer, dimension(nelemabs) :: numabs,ibegin_edge1,iend_edge1, &

src/specfem2D/specfem2D.F90

@@ -356,12 +356,14 @@ program specfem2D
 ! not work because it would be discontinuous at such an interface and would
 ! therefore not be consistent with the basis functions.
 
+#ifdef USE_MPI
+  use :: mpi
+#endif
 
   implicit none
 
   include "constants.h"
 #ifdef USE_MPI
-  include "mpif.h"
   include "precision.h"
 #endif
 

src/specfem2D/write_seismograms.F90

@@ -50,6 +50,10 @@ subroutine write_seismograms(sisux,sisuz,siscurl,station_name,network_name, &
       st_zval,x_source,z_source,SU_FORMAT,save_ASCII_seismograms, &
       save_binary_seismograms_single,save_binary_seismograms_double,subsamp_seismos)
 
+#ifdef USE_MPI
+  use :: mpi
+#endif
+
   implicit none
 
 ! uncomment this to save the ASCII *.sem* seismograms in binary instead, to save disk space and/or writing time
@@ -58,9 +62,6 @@ subroutine write_seismograms(sisux,sisuz,siscurl,station_name,network_name, &
 ! #define PAUL_SAVE_ASCII_IN_BINARY
 
   include "constants.h"
-#ifdef USE_MPI
-  include "mpif.h"
-#endif
 
   integer :: nrec,NSTEP,seismotype,subsamp_seismos
   integer :: NSTEP_BETWEEN_OUTPUT_SEISMOS,seismo_offset,seismo_current