doc: Add MPI-4.0 partial compliance features

docs/conf.py

@@ -52,8 +52,8 @@
 autoconf_min_version = f"{ompi_data['autoconf_min_version']}"
 libtool_min_version = f"{ompi_data['libtool_min_version']}"
 flex_min_version = f"{ompi_data['flex_min_version']}"
-mpi_standard_version = f"{ompi_data['mpi_standard_version']}"
-mpi_standard_subversion = f"{ompi_data['mpi_standard_subversion']}"
+mpi_standard_major_version = f"{ompi_data['mpi_standard_version']}"
+mpi_standard_minor_version = f"{ompi_data['mpi_standard_subversion']}"
 
 # "release" is a sphinx config variable: assign it to the computed
 # Open MPI version number.  The ompi_ver string begins with a "v"; the
@@ -219,8 +219,9 @@ def _doit(topdir):
 .. |autoconf_min_version| replace:: {autoconf_min_version}
 .. |libtool_min_version| replace:: {libtool_min_version}
 .. |flex_min_version| replace:: {flex_min_version}
-.. |mpi_standard_version| replace:: {mpi_standard_version}
-.. |mpi_standard_subversion| replace:: {mpi_standard_subversion}
+.. |mpi_standard_version| replace:: {mpi_standard_major_version}.{mpi_standard_minor_version}
+.. |mpi_standard_major_version| replace:: {mpi_standard_major_version}
+.. |mpi_standard_minor_version| replace:: {mpi_standard_minor_version}
 .. |deprecated_favor| replace:: this routine is deprecated in favor of
 
 """

docs/man-openmpi/man3/MPI_Get_version.3.rst

@@ -46,16 +46,19 @@ OUTPUT PARAMETERS
 -----------------
 
 * ``version`` : The major version number of the corresponding standard
-   (integer).
+  (integer).
 * ``subversion`` : The minor version number of the corresponding
-   standard (integer).
+  standard (integer).
 * ``ierror`` : Fortran only: Error status (integer).
 
 DESCRIPTION
 -----------
 
-Since Open MPI is MPI-|mpi_standard_version|.|mpi_standard_subversion| compliant, this function will return a
-``version`` value of |mpi_standard_version| and a subversion value of |mpi_standard_subversion| for this release.
+Since Open MPI |ompi_ver| is MPI-|mpi_standard_version| compliant (see
+:ref:`this page for more details about Open MPI standards conformance
+<mpi-standard-conformance-label>`) this function will return a
+``version`` value of |mpi_standard_major_version| and a ``subversion``
+value of |mpi_standard_minor_version| for this release.
 
 NOTE
 ----

docs/man-openmpi/man7/Open-MPI.7.rst

@@ -24,7 +24,7 @@ portable.
 
 The outcome, known as the MPI Standard, was first published in 1993; its
 most recent version (MPI-4.0) was published in June 2021. Open MPI
-includes all MPI |mpi_standard_version|.|mpi_standard_subversion|-compliant routines.
+includes all MPI |mpi_standard_version|-compliant routines.
 
 For more information about Open MPI, see https://www.open-mpi.org.
 

docs/release-notes/mpi.rst

@@ -1,12 +1,14 @@
 MPI Functionality and Features
 ==============================
 
+.. _mpi-standard-conformance-label:
+
 MPI Standard conformance
 ------------------------
 
-In the Open MPI |ompi_series| series, all MPI-|mpi_standard_version|.|mpi_standard_subversion| functionality is
-supported.  Some MPI-4.0 functionality is supported, but not all of
-it.
+In the Open MPI |ompi_series| series, all MPI-|mpi_standard_version|
+functionality is supported.  *Some* MPI-4.0 functionality is
+supported.
 
 As such, ``MPI_VERSION`` is set to 3 and ``MPI_SUBVERSION`` is set
 to 1.
@@ -31,6 +33,38 @@ For historical reference:
    * - MPI-3.1
      - Open MPI v2.0
 
+MPI-4.0 partial compliance
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+In the Open MPI |ompi_series| series, only partial MPI-4.0 functionality is
+supported. This section contains a list of features added for the release.
+
+* Added support for MPI Sessions.
+* Added partitioned communication using persistent sends and persistent receives.
+* Added persistent collectives to the ``MPI_`` namespace (they were previously
+  available via the ``MPIX_`` prefix).
+* Added support for :ref:`MPI_Isendrecv()<mpi_isendrecv>` and its variants.
+* Added support for :ref:`MPI_Comm_idup_with_info()<mpi_comm_idup_with_info>`.
+* Added support for :ref:`MPI_Info_get_string()<mpi_info_get_string>`.
+* Added support for ``initial_error_handler`` info key and the
+  ``MPI_ERRORS_ABORT`` infrastructure.
+* Added support for ``mpi_minimum_alignment`` info key.
+* Added support for ``MPI_COMM_TYPE_HW_GUIDED`` and
+  ``MPI_COMM_TYPE_HW_UNGUIDED``.
+* Added support for :ref:`MPI_Info_create_env()<mpi_info_create_env>`.
+* Added error handling for "unbound" errors to ``MPI_COMM_SELF``.
+* Added ``MPI_F_STATUS_SIZE``, ``MPI_F_SOURCE``, ``MPI_F_TAG``, and
+  ``MPI_F_ERROR``.
+* Made :ref:`MPI_Comm_get_info()<mpi_comm_get_info>`,
+  :ref:`MPI_File_get_info()<mpi_file_get_info>`, and
+  :ref:`MPI_Win_get_info()<mpi_win_get_info>` MPI-4.0 compliant.
+* Info keys that are not understood by Open MPI will be silently ignored and
+  dropped on communicators, files, and windows.
+* Deprecated :ref:`MPI_Sizeof()<mpi_sizeof>`.
+* Deprecated :ref:`MPI_Cancel()<mpi_cancel>` on send requests.
+* Deprecated :ref:`MPI_Info_get()<mpi_info_get>` and
+  :ref:`MPI_Info_get_valuelen()<mpi_info_get_valuelen>`.
+
 Removed MPI APIs
 ----------------