fortran/use-mpi-f08: revamp constant declarations

In order to work around an issue with flang based compilers,
avoid declaring bind(C) constants and use plain Fortran parameter
instead.

For example,
type(MPI_Comm), bind(C, name="ompi_f08_mpi_comm_world") OMPI_PROTECTED :: MPI_COMM_WORLD
is changed to
type(MPI_Comm), parameter :: MPI_COMM_WORLD = MPI_Comm(OMPI_MPI_COMM_WORLD)

Note that in order to preserve ABI compatibility, ompi/mpi/fortran/use-mpi-f08/constants.{c,h}
have been kept even if its symbols are no more referenced by Open MPI.

Refs. open-mpi#7091

Signed-off-by: Gilles Gouaillardet <[email protected]>

(back-ported from commit open-mpi/ompi@b10a60a)

Author: ggouaillardet

.gitignore

@@ -213,6 +213,7 @@ ompi/mpi/fortran/mpif-h/sizeof_f.f90
 ompi/mpi/fortran/mpif-h/profile/p*.c
 ompi/mpi/fortran/mpif-h/profile/psizeof_f.f90
 
+ompi/mpi/fortran/use-mpi-f08/mod/mpi-f08-constants.h
 ompi/mpi/fortran/use-mpi-f08/constants.h
 ompi/mpi/fortran/use-mpi-f08/sizeof_f08.f90
 ompi/mpi/fortran/use-mpi-f08/sizeof_f08.h

ompi/include/mpif-values.pl

@@ -1,8 +1,8 @@
 #!/usr/bin/env perl
 #
 # Copyright (c) 2011-2014 Cisco Systems, Inc.  All rights reserved.
-# Copyright (c) 2016-2017 Research Organization for Information Science
-#                         and Technology (RIST). All rights reserved.
+# Copyright (c) 2016-2019 Research Organization for Information Science
+#                         and Technology (RIST).  All rights reserved.
 # Copyright (c) 2016      FUJITSU LIMITED.  All rights reserved.
 # $COPYRIGHT$
 #
@@ -526,4 +526,62 @@ sub write_fortran_file {
 
 write_file("$topdir/ompi/mpi/fortran/use-mpi-f08/constants.h", $output);
 
+$output = '! WARNING! THIS IS A GENERATED FILE!!
+! ANY EDITS YOU PUT HERE WILL BE LOST!
+! Instead, edit topdir/ompi/include/mpif-values.pl
+!
+
+!
+! Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
+!                         University Research and Technology
+!                         Corporation.  All rights reserved.
+! Copyright (c) 2004-2006 The University of Tennessee and The University
+!                         of Tennessee Research Foundation.  All rights
+!                         reserved.
+! Copyright (c) 2004-2007 High Performance Computing Center Stuttgart,
+!                         University of Stuttgart.  All rights reserved.
+! Copyright (c) 2004-2005 The Regents of the University of California.
+!                         All rights reserved.
+! Copyright (c) 2007-2009 Cisco Systems, Inc.  All rights reserved.
+! Copyright (c) 2008-2009 Sun Microsystems, Inc.  All rights reserved.
+! Copyright (c) 2009      Oak Ridge National Labs.  All rights reserved.
+! Copyright (c) 2009-2012 Los Alamos National Security, LLC.
+!                         All rights reserved.
+! Copyright (c) 2016-2019 Research Organization for Information Science
+!                         and Technology (RIST). All rights reserved.
+! $COPYRIGHT$
+!
+! Additional copyrights may follow
+!
+! $HEADER$
+!
+
+#ifndef USE_MPI_F08_CONSTANTS_H
+#define USE_MPI_F08_CONSTANTS_H
+
+';
+
+foreach my $key (sort(keys(%{$constants}))) {
+    $output .= "#define OMPI_$key $constants->{$key}\n";
+}
+$output .= "\n";
+foreach my $key (sort(keys(%{$handles}))) {
+    $output .= "#define OMPI_$key $handles->{$key}\n";
+}
+
+foreach my $key (sort(keys(%{$io_constants}))) {
+    $output .= "#define OMPI_$key $io_constants->{$key}\n";
+}
+foreach my $key (sort(keys(%{$lio_constants}))) {
+    $output .= "#define OMPI_$key $lio_constants->{$key}\n";
+}
+$output .= "\n";
+foreach my $key (sort(keys(%{$io_handles}))) {
+    $output .= "#define OMPI_$key $io_handles->{$key}\n";
+}
+$output .= "\n";
+$output .= "#endif\n";
+
+write_file("$topdir/ompi/mpi/fortran/use-mpi-f08/mod/mpi-f08-constants.h", $output);
+
 exit(0);

ompi/mpi/fortran/use-mpi-f08/mod/Makefile.am

@@ -48,6 +48,7 @@ libforce_usempif08_internal_modules_to_be_built_la_SOURCES = \
         mpi-f08-interfaces.F90 \
         mpi-f08-interfaces-callbacks.F90 \
         mpi-f08-callbacks.F90 \
+        mpi-f08-constants.h \
         pmpi-f08-interfaces.F90
 
 config_h = \