Enable workarounds when mpi.mod is incompatible

 Fall back to using `#include 'mpif.h'`
 Create interfaces when needed

# Please enter the commit message for your changes. Lines starting
# with '#' will be ignored, and an empty message aborts the commit.
# On branch #246-gfortran-mpich-mismatch-detection
# Changes to be committed:
#	modified:   ../CMakeLists.txt
#	modified:   ../src/extensions/opencoarrays.F90
#	modified:   ../src/mpi/CMakeLists.txt
#	modified:   ../src/tests/integration/dist_transpose/coarray_distributed_transpose.F90
#	modified:   ../src/tests/integration/pde_solvers/navier-stokes/coarray-shear_coll.F90
#	modified:   ../src/tests/performance/BurgersMPI/shared.F90
#	modified:   ../src/tests/performance/mpi_dist_transpose/mpi_distributed_transpose.F90
#	modified:   ../src/tests/unit/init_register/CMakeLists.txt
#	renamed:    ../src/tests/unit/init_register/initialize_mpi.f90 -> ../src/tests/unit/init_register/initialize_mpi.F90
#
# Untracked files:
#	../.travis-scripts/
#	./
#

Author: zbeekman

CMakeLists.txt

@@ -252,7 +252,9 @@ if ( (NOT MPI_Fortran_MODULE_COMPILES) AND (NOT MPI_Fortran_INCLUDE_COMPILES) )
     )
 endif()
 
-if ( NOT MPI_Fortran_MODULE_COMPILES )
+if ( MPI_Fortran_MODULE_COMPILES )
+  add_definitions(-DMPI_WORKING_MODULE)
+else()
   message ( WARNING "It appears that MPI was built with a different Fortran compiler. "
     "It is possible that this may cause unpredictable behavior. The build will continue "
     "using `mpif.h` BUT please report any suspicious behavior to the OpenCoarrays "

src/extensions/opencoarrays.F90

@@ -32,6 +32,10 @@ module opencoarrays
   use iso_c_binding, only : c_int,c_char,c_ptr,c_loc,c_double,c_int32_t,c_ptrdiff_t,c_sizeof,c_bool,c_funloc
   implicit none
 
+#ifndef MPI_WORKING_MODULE
+#include 'mpif.h'
+#endif
+
   private
   public :: co_reduce
   public :: co_broadcast
@@ -726,7 +730,9 @@ subroutine co_sum_c_int(a,result_image,stat,errmsg)
 
   ! Return the image number (MPI rank + 1)
   function this_image()  result(image_num)
+#ifdef MPI_WORKING_MODULE
     use mpi, only : MPI_Comm_rank
+#endif
     integer(c_int) :: image_num,ierr
    !image_num = opencoarrays_this_image(unused)
     call MPI_Comm_rank(CAF_COMM_WORLD,image_num,ierr)
@@ -736,7 +742,9 @@ function this_image()  result(image_num)
 
   ! Return the total number of images
   function num_images()  result(num_images_)
+#ifdef MPI_WORKING_MODULE
     use mpi, only : MPI_Comm_size
+#endif
     integer(c_int) :: num_images_,ierr
    !num_images_ = opencoarrays_num_images(unused_coarray,unused_scalar)
     call MPI_Comm_size(CAF_COMM_WORLD,num_images_,ierr)

src/mpi/CMakeLists.txt

@@ -34,18 +34,6 @@ endif()
 if (MPI_Fortran_MODULE_COMPILES)
   # likely the same compiler compiled MPI
   set(MPI_CAF_FORTRAN_FILES ../extensions/opencoarrays.F90)
-elseif(MPI_Fortran_INCLUDE_COMPILES)
-  # Likely a different version or completely different Fortran compiler built MPI
-  # Since the .mod file is incompatible hack together a replacement
-  file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/my_mpi_mod.f90"
-    "
-    module mpi
-    implicit none
-    public
-    include 'mpif.h'
-    end module"
-    )
-  set(MPI_CAF_FORTRAN_FILES "${CMAKE_CURRENT_BINARY_DIR}/my_mpi_mod.f90" ../extensions/opencoarrays.F90 )
 endif()
 
 add_library(caf_mpi mpi_caf.c ../common/caf_auxiliary.c ${MPI_CAF_FORTRAN_FILES})

src/tests/integration/dist_transpose/coarray_distributed_transpose.F90

@@ -35,9 +35,21 @@
 module run_size
     use iso_fortran_env
 #ifndef HAVE_WALLTIME
-    use MPI, only : WALLTIME=>MPI_WTIME
+#  ifdef MPI_WORKING_MODULE
+     use MPI, only : WALLTIME=>MPI_WTIME
+     implicit none
+#  else
+     implicit none
+#    include 'mpif.h'
+     interface WALLTIME
+       function MPI_WTIME() result(res)
+         double precision :: res
+       end function
+    end interface WALLTIME
+#  endif
+#else
+  implicit none
 #endif
-    implicit none
         integer(int64), codimension[*] :: nx, ny, nz
         integer(int64), codimension[*] :: my, mx, first_y, last_y, first_x, last_x
         integer(int64) :: my_node, num_nodes

src/tests/integration/pde_solvers/navier-stokes/coarray-shear_coll.F90

@@ -112,9 +112,21 @@ module run_size
     use iso_fortran_env, only : int64,real64 ! 64-bit integer and real kind parameters
     use constants_module, only : one         ! 64-bit unit to ensure argument kind match
 #ifndef HAVE_WALLTIME
-    use MPI, only : WALLTIME=>MPI_WTIME
+#  ifdef MPI_WORKING_MODULE
+     use MPI, only : WALLTIME=>MPI_WTIME
+     implicit none
+#  else
+     implicit none
+#    include 'mpif.h'
+     interface WALLTIME
+       function MPI_WTIME() result(res)
+         double precision :: res
+       end function
+    end interface WALLTIME
+#  endif
+#else
+  implicit none
 #endif
-    implicit none
         real, codimension[*] ::  viscos, shear, b11, b22, b33, b12, velmax
         integer(int64), codimension[*] ::  nx, ny, nz, nsteps, output_step
         integer(int64), codimension[*] :: my, mx, first_y, last_y, first_x, last_x

src/tests/performance/BurgersMPI/shared.F90

@@ -26,7 +26,11 @@
 
 module shared
   !module for sharing mpi functionality/variables with other modules/main
+#ifdef MPI_WORKING_MODULE
   use mpi !non-native mpi functionality
+#else
+# include 'mpif.h'
+#endif
   integer :: tag, status(MPI_STATUS_SIZE)
   integer :: MPI_COMM_CART
   integer :: my_id, num_procs, ierr, local_grid_resolution, left_id, right_id

src/tests/performance/mpi_dist_transpose/mpi_distributed_transpose.F90

@@ -38,9 +38,21 @@
 module mpi_run_size
     use iso_fortran_env
 #ifndef HAVE_WALLTIME
-    use MPI, only : WALLTIME=>MPI_WTIME
+#  ifdef MPI_WORKING_MODULE
+     use MPI, only : WALLTIME=>MPI_WTIME
+     implicit none
+#  else
+     implicit none
+#    include 'mpif.h'
+     interface WALLTIME
+       function MPI_WTIME() result(res)
+         double precision :: res
+       end function
+    end interface WALLTIME
+#  endif
+#else
+  implicit none
 #endif
-    implicit none
         integer(int64) :: nx, ny, nz
         integer(int64) :: my, mx, first_y, last_y, first_x, last_x
         integer(int64) :: my_node, num_nodes

src/tests/unit/init_register/CMakeLists.txt

@@ -1,4 +1,4 @@
-add_executable(initialize_mpi initialize_mpi.f90)
+add_executable(initialize_mpi initialize_mpi.F90)
 target_link_libraries(initialize_mpi OpenCoarrays)
 
 add_executable(register register.f90)

src/tests/unit/init_register/initialize_mpi.f90 renamed to src/tests/unit/init_register/initialize_mpi.F90

@@ -26,8 +26,19 @@
 ! SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 !
 program initialize_mpi
+#ifdef MPI_WORKING_MODULE
   use mpi, only : MPI_COMM_SIZE,MPI_COMM_WORLD
   implicit none
+#else
+  implicit none
+# include 'mpif.h'
+  interface
+     subroutine MPI_COMM_SIZE(mpi_comm,nranks,ierr)
+       integer, intent(in)  :: mpi_comm
+       integer, intent(out) :: nranks, ierr
+     end subroutine
+  end interface
+#endif
 
   ! Set invalid default image number and number of ranks
   integer :: me=-1,np=-1,ierr