path: root/release_docs/RELEASE.txt

HDF5 version 1.10.9-1 currently under development
================================================================================


INTRODUCTION
============

This document describes the differences between this release and the previous
HDF5 release. It contains information on the platforms tested and known
problems in this release. For more details check the HISTORY*.txt files in the
HDF5 source.

Note that documentation in the links below will be updated at the time of each
final release.

Links to HDF5 documentation can be found on The HDF5 web page:

     https://portal.hdfgroup.org/display/HDF5/HDF5

The official HDF5 releases can be obtained from:

     https://www.hdfgroup.org/downloads/hdf5/

Changes from Release to Release and New Features in the HDF5-1.10.x release series
can be found at:

     https://portal.hdfgroup.org/display/HDF5/HDF5+Application+Developer%27s+Guide

If you have any questions or comments, please send them to the HDF Help Desk:

     help@hdfgroup.org


CONTENTS
========

- New Features
- Support for new platforms and languages
- Bug Fixes since HDF5-1.10.8
- Supported Platforms
- Tested Configuration Features Summary
- More Tested Platforms
- Known Problems
- CMake vs. Autotools installations


New Features
============

    Configuration:
    -------------
    - Added new option to the h5cc scripts produced by CMake.

      Add -showconfig option to h5cc scripts to cat the 
      libhdf5-settings to the standard output.

      (ADB - 2022/03/11)

    - HDF5 memory allocation sanity checking is now off by default for
      Autotools debug builds

      HDF5 can be configured to perform sanity checking on internal memory
      allocations by adding heap canaries to these allocations. However,
      enabling this option can cause issues with external filter plugins
      when working with (reallocating/freeing/allocating and passing back)
      buffers.

      Previously, this option was off by default for all CMake build types,
      but only off by default for non-debug Autotools builds. Since debug
      is the default build mode for HDF5 when built from source with
      Autotools, this can result in surprising segfaults that don't occur
      when an application is built against a release version of HDF5.
      Therefore, this option is now off by default for all build types
      across both CMake and Autotools.

      (JTH - 2022/03/01)

    - Refactored the utils folder.

      Added subfolder test and moved the 'swmr_check_compat_vfd.c file'
      from test into utils/test. Deleted the duplicate swmr_check_compat_vfd.c
      file in hl/tools/h5watch folder. Also fixed vfd check options.

      (ADB - 2021/10/18)

    - Changed autotools and CMake configurations to derive both
      compilation warnings-as-errors and warnings-only-warn configurations
      from the same files, 'config/*/*error*'.  Removed redundant files
      'config/*/*noerror*'.

      (DCY - 2021/09/29)


    Library:
    --------
    -


    Fortran Library:
    ----------------
    - 


    C++ Library:
    ------------
    -


    Java Library:
    -------------
    - 


    Tools:
    ------
    - 


    High-Level APIs:
    ----------------
    -


    C Packet Table API:
    -------------------
    -


    Internal header file:
    ---------------------
    -


    Documentation:
    --------------
    -


Support for new platforms, languages and compilers
==================================================
    -


Bug Fixes since HDF5-1.10.7 release
===================================
    Library
    -------
    - Issue #1436 identified a problem with the H5_VERS_RELEASE check in the
      H5check_version function.

      Investigating the original fix, #812, we discovered some inconsistencies
      with a new block added to check H5_VERS_RELEASE for incompatibilities.
      This new block was not using the new warning text dealing with the
      H5_VERS_RELEASE check and would cause the warning to be duplicated.

      By removing the H5_VERS_RELEASE argument in the first check for 
      H5_VERS_MAJOR and H5_VERS_MINOR, the second check would only check
      the H5_VERS_RELEASE for incompatible release versions. This adheres
      to the statement that except for the develop branch, all release versions
      in a major.minor maintenance branch should be compatible. The prerequisite
      is that an application will not use any APIs not present in all release versions.

      (ADB - 2022/03/11, #1438)

    - Unified handling of collective metadata reads to correctly fix old bugs

      Due to MPI-related issues occurring in HDF5 from mismanagement of the
      status of collective metadata reads, they were forced to be disabled
      during chunked dataset raw data I/O in the HDF5 1.10.5 release. This
      wouldn't generally have affected application performance because HDF5
      already disables collective metadata reads during chunk lookup, since
      it is generally unlikely that the same chunks will be read by all MPI
      ranks in the I/O operation. However, this was only a partial solution
      that wasn't granular enough.

      This change now unifies the handling of the file-global flag and the
      API context-level flag for collective metadata reads in order to
      simplify querying of the true status of collective metadata reads. Thus,
      collective metadata reads are once again enabled for chunked dataset
      raw data I/O, but manually controlled at places where some processing
      occurs on MPI rank 0 only and would cause issues when collective
      metadata reads are enabled.

      (JTH - 2021/11/16, HDFFV-10501/HDFFV-10562)

    - Fixed several potential MPI deadlocks in library failure conditions

      In the parallel library, there were several places where MPI rank 0
      could end up skipping past collective MPI operations when some failure
      occurs in rank 0-specific processing. This would lead to deadlocks
      where rank 0 completes an operation while other ranks wait in the
      collective operation. These places have been rewritten to have rank 0
      push an error and try to cleanup after the failure, then continue to
      participate in the collective operation to the best of its ability.

      (JTH - 2021/11/09)

    - Fixed an issue with collective metadata reads being permanently disabled
      after a dataset chunk lookup operation. This would usually cause a
      mismatched MPI_Bcast and MPI_ERR_TRUNCATE issue in the library for
      simple cases of H5Dcreate() -> H5Dwrite() -> H5Dcreate().

      (JTH - 2021/11/08, HDFFV-11090)

    Java Library
    ------------
    - 


    Configuration
    -------------
    - Reworked corrected path searched by CMake find_package command

      The install path for cmake find_package files had been changed to use
        "share/cmake"
      for all platforms. However setting the HDF5_ROOT variable failed to locate
      the configuration files. The build variable HDF5_INSTALL_CMAKE_DIR is now
      set to the <INSTALL_DIR>/cmake folder. The location of the configuration 
      files can still be specified by the "HDF5_DIR" variable.

      (ADB - 2022/03/11)


    Tools
    -----
    - 


    Fortran API
    -----------
    -


    High-Level Library
    ------------------
    - Fixed HL_test_packet, test for packet table vlen of vlen.

      Incorrect length assignment.

        (ADB - 2021/10/14)


    Fortran High-Level APIs
    -----------------------
    -


    Documentation
    -------------
    - 


    F90 APIs
    --------
    -


    C++ APIs
    --------
    - 


    Testing
    -------
    -


Supported Platforms
===================

    Linux 3.10.0-1127.10.1.el7    gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39)
    #1 SMP ppc64 GNU/Linux        g++ (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39)
    (echidna)                     GNU Fortran (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39)

    Linux 2.6.32-754.31.1.el6     IBM XL C/C++ V13.1
    #1 SMP ppc64 GNU/Linux        IBM XL Fortran V15.1
    (ostrich)

    Linux 3.10.0-327.18.2.el7     GNU C (gcc), Fortran (gfortran), C++ (g++)
    #1 SMP x86_64 GNU/Linux       compilers:
    (jelly/kituo/moohan)          Version 4.8.5 20150623 (Red Hat 4.8.5-4)
                                    Version 4.9.3, Version 5.3.0, Version 6.3.0,
                                    Version 7.2.0, Version 8.3.0, Version 9.1.0
                                  Intel(R) C (icc), C++ (icpc), Fortran (icc)
                                  compilers:
                                     Version 17.0.0.098 Build 20160721
                                  MPICH 3.3 compiled with GCC 7.2.0
                                  OpenMPI 4.0.0 compiled with GCC 7.2.0

    SunOS 5.11 11.4.5.12.5.0      Sun C 5.15 SunOS_sparc 2017/05/30
    32- and 64-bit                Studio 12.6 Fortran 95 8.8 SunOS_sparc 2017/05/30
    (hedgehog)                    Sun C++ 5.15 SunOS_sparc 2017/05/30

    Windows 10 x64                Visual Studio 2015 w/ Intel Fortran 18 (cmake)
                                  Visual Studio 2017 w/ Intel Fortran 19 (cmake)
                                  Visual Studio 2019 w/ Intel Fortran 19 (cmake)
                                  Visual Studio 2019 w/ MSMPI 10.1 (cmake)

    macOS Mojave 10.14.6          Apple LLVM version 10.0.1 (clang-1001.0.46.4)
    64-bit                        gfortran GNU Fortran (GCC) 6.3.0
    (swallow)                     Intel icc/icpc/ifort version 19.0.4.233 20190416

Tested Configuration Features Summary
=====================================

    In the tables below
          y   = tested
          n   = not tested in this release
          C   = Cluster
          W   = Workstation
          x   = not working in this release
          dna = does not apply
          ( ) = footnote appears below second table
          <blank> = testing incomplete on this feature or platform

Platform                              C         F90/   F90      C++  zlib  SZIP
                                      parallel  F2003  parallel
Solaris2.11 32-bit                      n        y/y    n        y    y     y
Solaris2.11 64-bit                      n        y/n    n        y    y     y
Windows 10                              y        y/y    n        y    y     y
Windows 10 x64                          y        y/y    n        y    y     y
Mac OS X El Capitan 10.11.6 64-bit      n        y/y    n        y    y     y
Mac OS Sierra 10.12.6 64-bit            n        y/y    n        y    y     y
Mac OS X High Sierra 10.13.6 64-bit     n        y/y    n        y    y     y
Mac OS X Mojave 10.14.6 64-bit          n        y/y    n        y    y     y
CentOS 7.2 Linux 2.6.32 x86_64 PGI      n        y/y    n        y    y     y
CentOS 7.2 Linux 2.6.32 x86_64 GNU      y        y/y    y        y    y     y
CentOS 7.2 Linux 2.6.32 x86_64 Intel    n        y/y    n        y    y     y
Linux 2.6.32-573.18.1.el6.ppc64         n        y/y    n        y    y     y


Platform                                 Shared  Shared    Shared    Thread-
                                         C libs  F90 libs  C++ libs  safe
Solaris2.11 32-bit                         y       y         y         y
Solaris2.11 64-bit                         y       y         y         y
Windows 10                                 y       y         y         y
Windows 10 x64                             y       y         y         y
Mac OS X El Capitan 10.11.6 64-bit         y       n         y         y
Mac OS Sierra 10.12.6 64-bit               y       n         y         y
Mac OS X High Sierra 10.13.6 64-bit        y       n         y         y
Mac OS X Mojave 10.14.6 64-bit             y       n         y         y
CentOS 7.2 Linux 2.6.32 x86_64 PGI         y       y         y         n
CentOS 7.2 Linux 2.6.32 x86_64 GNU         y       y         y         y
CentOS 7.2 Linux 2.6.32 x86_64 Intel       y       y         y         n
Linux 2.6.32-573.18.1.el6.ppc64            y       y         y         n

Compiler versions for each platform are listed in the preceding
"Supported Platforms" table.


More Tested Platforms
=====================
The following platforms are not supported but have been tested for this release.

    Linux 2.6.32-573.22.1.el6    GNU C (gcc), Fortran (gfortran), C++ (g++)
    #1 SMP x86_64 GNU/Linux       compilers:
    (platypus)                       Version 4.4.7 20120313
                                     Version 4.9.3, 5.3.0, 6.2.0
                                  PGI C, Fortran, C++ for 64-bit target on
                                  x86-64;
                                     Version 19.10-0
                                  MPICH 3.1.4 compiled with GCC 4.9.3

    Linux 2.6.32-754.31.1.el6     gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-18)
    #1 SMP ppc64 GNU/Linux        g++ (GCC) 4.4.7 20120313 (Red Hat 4.4.7-18)
    (ostrich)                     GNU Fortran (GCC) 4.4.7 20120313 (Red Hat 4.4.7-18)

    Linux 3.10.0-327.18.2.el7     GNU C (gcc) and C++ (g++) compilers
    #1 SMP x86_64 GNU/Linux          Version 4.8.5 20150623 (Red Hat 4.8.5-4)
    (jelly)                       with NAG Fortran Compiler Release 6.1(Tozai)
                                  GCC Version 7.1.0
                                  OpenMPI 2.1.6-GCC-7.2.0-2.29,
                                     3.1.3-GCC-7.2.0-2.29
                                  Intel(R) C (icc) and C++ (icpc) compilers
                                     Version 17.0.0.098 Build 20160721
                                  with NAG Fortran Compiler Release 6.1(Tozai)

    Linux 3.10.0-327.10.1.el7     MPICH 3.1.4 compiled with GCC 4.9.3
    #1 SMP x86_64 GNU/Linux
    (moohan)

    Linux-3.10.0-1127.0.0.1chaos  openmpi-4.0.0
    #1 SMP x86_64 GNU/Linux           clang/3.9.0, 8.0.1
    (quartz)                          gcc/7.3.0, 8.1.0
                                      intel/16.0.4

    Linux-4.14.0-115.10.1.1       spectrum-mpi/rolling-release
    #1 SMP ppc64le GNU/Linux          clang/coral-2018.08.08
    (lassen)                          gcc/7.3.1
                                      xl/2019.02.07

    Linux-4.12.14-150.52-default  cray-mpich/7.7.10
    #1 SMP x86_64 GNU/Linux           gcc/7.3.0, 8.2.0
    (cori)                            intel/19.0.3

    Linux-4.4.180-94.107-default  cray-mpich/7.7.6
    # 1SMP x86_64 GNU/Linux           gcc/7.2.0, 8.2.0
    (mutrino)                         intel/17.0.4, 18.0.2, 19.0.4

    Fedora33 5.10.10-200.fc33.x86_64
    #1 SMP x86_64  GNU/Linux         GNU gcc (GCC) 10.2.1 20201125 (Red Hat 10.2.1-9)
                                     GNU Fortran (GCC) 10.2.1 20201125 (Red Hat 10.2.1-9)
                                     clang version 11.0.0 (Fedora 11.0.0-2.fc33)
                                     (cmake and autotools)

    Ubuntu20.10 5.8.0-41-generic-x86_64
    #46-Ubuntu SMP x86_64  GNU/Linux GNU gcc (GCC) 10.2.0-13ubuntu1
                                     GNU Fortran (GCC) 10.2.0-13ubuntu1
                                     (cmake and autotools)

    SUSE15sp2 5.3.18-22-default
    #1 SMP x86_64  GNU/Linux         GNU gcc (SUSE Linux) 7.5.0
                                     GNU Fortran (SUSE Linux) 7.5.0
                                     clang version 7.0.1 (tags/RELEASE_701/final 349238)
                                     (cmake and autotools)

    Mac OS X El Capitan 10.11.6   Apple clang version 7.3.0 from Xcode 7.3
    64-bit                        gfortran GNU Fortran (GCC) 5.2.0
    (osx1011test)                 Intel icc/icpc/ifort version 16.0.2

    macOS Sierra 10.12.6          Apple LLVM version 9.0.0 (clang-900.39.2)
    64-bit                        gfortran GNU Fortran (GCC) 7.4.0
    (kite)                        Intel icc/icpc/ifort version 17.0.2

    macOS High Sierra 10.13.6     Apple LLVM version 10.0.0 (clang-1000.10.44.4)
    64-bit                        gfortran GNU Fortran (GCC) 6.3.0
    (bear)                        Intel icc/icpc/ifort version 19.0.4.233 20190416

    SunOS 5.11 11.3               Sun C 5.15 SunOS_sparc
    32- and 64-bit                Sun Fortran 95 8.8 SunOS_sparc
    (emu)


Known Problems
==============
    Setting a variable-length dataset fill value will leak the memory allocated
    for the p field of the hvl_t struct. A fix is in progress for this.
    HDFFV-10840

    CMake files do not behave correctly with paths containing spaces.
    Do not use spaces in paths because the required escaping for handling spaces
    results in very complex and fragile build files.
    ADB - 2019/05/07

    At present, metadata cache images may not be generated by parallel
    applications.  Parallel applications can read files with metadata cache
    images, but since this is a collective operation, a deadlock is possible
    if one or more processes do not participate.

    Two tests fail attempting collective writes with OpenMPI 3.0.0/GCC-7.2.0-2.29:
        testphdf5 (ecdsetw, selnone, cchunk1, cchunk3, cchunk4, and actualio)
        t_shapesame (sscontig2)

    CPP ptable test fails on both VS2017 and VS2019 with Intel compiler, JIRA
    issue: HDFFV-10628.  This test will pass with VS2015 with Intel compiler.

    The subsetting option in ph5diff currently will fail and should be avoided.
    The subsetting option works correctly in serial h5diff.

    Known problems in previous releases can be found in the HISTORY*.txt files
    in the HDF5 source. Please report any new problems found to
    help@hdfgroup.org.


CMake vs. Autotools installations
=================================
While both build systems produce similar results, there are differences.
Each system produces the same set of folders on linux (only CMake works
on standard Windows); bin, include, lib and share. Autotools places the
COPYING and RELEASE.txt file in the root folder, CMake places them in
the share folder.

The bin folder contains the tools and the build scripts. Additionally, CMake
creates dynamic versions of the tools with the suffix "-shared". Autotools
installs one set of tools depending on the "--enable-shared" configuration
option.
  build scripts
  -------------
  Autotools: h5c++, h5cc, h5fc
  CMake: h5c++, h5cc, h5hlc++, h5hlcc

The include folder holds the header files and the fortran mod files. CMake
places the fortran mod files into separate shared and static subfolders,
while Autotools places one set of mod files into the include folder. Because
CMake produces a tools library, the header files for tools will appear in
the include folder.

The lib folder contains the library files, and CMake adds the pkgconfig
subfolder with the hdf5*.pc files used by the bin/build scripts created by
the CMake build. CMake separates the C interface code from the fortran code by
creating C-stub libraries for each Fortran library. In addition, only CMake
installs the tools library. The names of the szip libraries are different
between the build systems.

The share folder will have the most differences because CMake builds include
a number of CMake specific files for support of CMake's find_package and support
for the HDF5 Examples CMake project.