path: root/release_docs/RELEASE.txt

HDF5 version 1.8.16-snap16 currently under development
================================================================================

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

This document describes the differences between HDF5-1.8.15 and
HDF5-1.8.16-*, and contains information on the platforms tested and
known problems in HDF5-1.8.16-*.
For more details, see the files HISTORY-1_0-1_8_0_rc3.txt
and HISTORY-1_8.txt in the release_docs/ directory of the HDF5 source.

Links to the HDF5 1.8.15 source code, documentation, and additional materials
can be found on the HDF5 web page at:

     http://www.hdfgroup.org/products/hdf5/

The HDF5 1.8.15 release can be obtained from:

     http://www.hdfgroup.org/HDF5/release/obtain5.html

User documentation for 1.8.15 can be accessed directly at this location:

     http://www.hdfgroup.org/HDF5/doc/

New features in the HDF5-1.8.x release series, including brief general
descriptions of some new and modified APIs, are described in the "What's New
in 1.8.0?" document:

     http://www.hdfgroup.org/HDF5/doc/ADGuide/WhatsNew180.html

All new and modified APIs are listed in detail in the "HDF5 Software Changes
from Release to Release" document, in the section "Release 1.8.16 (current
release) versus Release 1.8.15

     http://www.hdfgroup.org/HDF5/doc/ADGuide/Changes.html

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, Languages, and Compilers
- Bug Fixes since HDF5-1.8.15
- Supported Platforms
- Supported Configuration Features Summary
- More Tested Platforms
- Known Problems


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

    Configuration
    -------------
    - The thread-safety + high-level library combination has been marked
      as "unsupported" in the Autotools

      The global lock used by the thread-safety feature has never been
      raised to the high-level library level, making it possible that
      library state could change if a context switch were to occur in
      a high-level library call. Because of this, the combination of
      thread-safety and high-level library is officially unsupported by
      The HDF Group.

      In the past, although this combination has never been supported, this
      was not enforced by the build systems. These changes will cause an
      Autotools configure step to fail if --enable-threadsafe and
      --enable-hl are combined unless additional options are specified.
      Since the high-level library is built by default, this means that
      these extra configuration options will need to be used any time
      --enable-threadsafe is selected.

      To build with --enable-threadsafe, either:

      1) Use --disable-hl to disable the high-level library (recommended)

      2) Use --enable-unsupported to build the high-level library with
         the thread-safety feature.

      (DER - 2015/09/10 HDFFV-8719)

    - Using CMake now builds both static and shared libraries.

      The CMake files have been updated to build both static and shared
      libraries, with tools only built statically. The packaging of the
      libraries and tools will include cmake-config files that allows
      projects to choose either shared or static (default) libraries
      to be found with the find_package command using the COMPONENTS
      keyword and a list of components. The imported libraries will
      include any interface specific settings and dependent libraries.

      The default setting for BUILD_SHARED_LIBS has changed from OFF
      to ON, which builds both static and shared libraries. The static
      libraries are always built because of tools requirements.

      (ADB - 2015/08/24 HDFFV-5881)

    - Inline functions now correctly annotated w/ Autotools builds.

      The method used to detect the appropriate inline markup scheme was
      nonfunctional in Autotools builds. The Autotools have been modified
      to correctly detect the compiler's inline markup symbol and apply it
      to the source. Note that only a very small number of internal
      functions are marked inline so this was not a very big change or
      likely to significantly affect performance.

      As a part of this change, the H5_inline symbol no longer appears in
      H5pubconf.h.

      (DER - 2015/08/13 HDFFV-9119, HDFFV-9421)

    - Removed obsolete/unmaintained files from config/

      Several files were removed from the config directory. These files
      represent old operating systems, were no longer necessary, and/or
      were no longer maintained. configure.ac was updated to reflect the
      removed files.

      Removed:

        craynv
        dec-flags
        hpux11.23
        ia64-linux-gnu
        nec-superux14.1
        sv1-cray
        x86_64-redstorm-linux-gnu
        powerpc-ibm-aix5.x

      As a part of this work, a few lines that deal with locating the
      sys/fpu.h header on SGI machines and some OSF/1 configure lines
      were also removed. The Solaris config was also renamed to not have
      a version number since the version number was ignored by configure
      as it applies to all Solaris versions.

      (DER - 2015/09/04 HDFFV-9116)

    - Removed the FP_TO_INTEGER_OVERFLOW_WORKS macro/defines from the library

      This was for working around bugs in the Cray X1 compiler, which is no
      longer supported.

    (DER - 2015/09/09 HDFFV-9191) 

    - Removed the H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS and
      H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS symbols and associated code.

      H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS was a work-around on old 64-bit
      SGI and Solaris systems.

      H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS was a work-around for old PGI
      compilers on Linux.

      Neither of these were used in any current library code and only appeared
      in the dt_arith test.

      (DER - 2015/09/09 HDFFV-9187)

    - Removed CONVERT_DENORMAL_FLOAT symbol and associated code from the
      library.

      This was only set in configure files for Cray and NEC computers. These
      config files no longer exist so there is no effect on currently
      supported platforms.

      (DER - 2015/09/09 HDFFV-9188)

    - Removed WANT_DATA_ACCURACY symbol and associated code from the
      library.

      This is no longer attached to any supported platforms.

      (DER - 2015/09/09 HDFFV-9194)

    - Removed _BSD_SOURCE and _DEFAULT_SOURCE from configure.ac

      These are old BSD-compatibility symbols that are no longer needed by
      the library.

      (DER - 2015/09/10 HDFFV-9079)

    - Removed HW_FP_TO_LLONG_NOT_WORKS symbol and associated code from the
      library.

      This was part of a work-around for the VS.NET 2003 compiler, which is
      no longer supported.

      (DER - 2015/09/10 HDFFV-9189)

    - Removed LDOUBLE_TO_LLONG_ACCURATE symbol and associated code from the
      library.

      This was part of a work-around for VS.NET 2003, 64-bit IRIX 6.5,
      OS X 10.4, and some versions of HP/UX, none of which are currently
      supported.

      (DER - 2015/09/10 HDFFV-9192)

    - Removed LLONG_TO_LDOUBLE_CORRECT symbol and associated code from the
      library.

      This was a part of a work-around for Visual Studio 6, OS X 10.4,
      IRIX 6.5, and very old versions of FreeBSD and 64-bit Solaris. None
      of these platforms/compilers are currently supported.

      (DER - 2015/09/10 HDFFV-9193)

    - Removed the BAD_LOG2_CODE_GENERATED symbol and associated code from the
      library.

      This was an IRIX work-around.

      (DER - 2015/09/11 HDFFV-9195)

    Library
    -------

    - H5F_ACC_DEBUG flag for H5Fopen/create: functionality removed

      The symbol was used to emit some extra debugging information
      for HDF Group developers in the multi VFD. The underlying
      functionality has been removed due to disuse. The symbol
      remains defined since it was visible in H5Fpublic.h but it
      has been set to zero and has no effect anywhere in the library.

      (DER - 2015-05-02, HDFFV-1074)

    - New public API call: H5is_library_threadsafe()

      This API call indicates if the library was built with thread-
      safety enabled.

      (DER - 2015-09-01, HDFFV-9496)

    Parallel Library
    ----------------
    -
      (XYZ - YYYY/MM/DD HDFFV-####)

    Tools
    -----
    - None

    High-Level APIs
    ---------------
    - None

    Fortran API
    -----------
    -
      (XYZ - YYYY/MM/DD HDFFV-####)


    C++ API
    -------
    - None



Support for New Platforms, Languages, and Compilers
===================================================
    -
    -

Bug Fixes since HDF5-1.8.15
===========================

    Configuration
    -------------

    - None

    Library
    -------
    - Fix potential error in H5Iclear_type

      If the ID type's close callback could close another ID of the same type,
      H5Iclear_type could occasionally run into problems due to the inner
      workings of the skip list package.  This could potentially cause an
      error on library shutdown without calling H5Iclear_type directly.  This
      issue has been fixed.

      (NAF - 2015-08-12)

    - Fix uninitialized memory in dataspace selection code

      When creating a dataspace with H5Screate and setting the extent with
      H5Sextent_copy, the selection offset was not initialized, potentially
      causing invalid I/O.  There may be other cases where this happened.
      MOdified library to always initialize the offset.

      (NAF - 2015-09-08)


    Parallel Library
    ----------------
    -
      (XYZ - YYYY/MM/DD HDFFV-####)

    Performance
    -------------
    - None

    Tools
    -----
    - Fix h5repack with UD filters

      h5repack would throw a buffer overrun exception on Windows when
      parsing a UD filter id of 5 digits. A local variable in the parse
      routine was not of sufficient size.

      (ADB - 2015/09/01 HDFFV-9515)

    Fortran API
    ------------
    -
      (XYZ - YYYY/MM/DD HDFFV-####)


    C++ API
    ------
    - None

    High-Level APIs:
    ------
    -
      (XYZ - YYYY/MM/DD HDFFV-####)


    Fortran High-Level APIs:
    ------------------------
    -
      (XYZ - YYYY/MM/DD HDFFV-####)


    Testing
    -------
    - None


Supported Platforms
===================
The following platforms are supported and have been tested for this release.
They are built with the configure process unless specified otherwise.

    AIX 6.1                       xlc/xlc_r 10.1.0.5
    (NASA G-ADA)                  xlC/xlC_r 10.1.0.5
                                  xlf90/xlf90_r 12.1.0.6

    Linux 2.6.18-308.13.1.el5PAE  GNU C (gcc), Fortran (gfortran), C++ (g++)
    #1 SMP i686 i686 i386         compilers for 32-bit applications;
    (jam)                             Version 4.1.2 20080704 (Red Hat 4.1.2-55)
                                      Version 4.8.4, 4.9.2
                                  PGI C, Fortran, C++ Compilers for 32-bit
                                  applications;
                                      Version 14.10-0
                                  Intel(R) C, C++, Fortran Compiler for 32-bit
                                  applications;
                                      Version 15.0.1.133 (Build 20141023)

    Linux 2.6.18-371.6.1.el5      GNU C (gcc), Fortran (gfortran), C++ (g++)
    #1 SMP x86_64 GNU/Linux       compilers for 64-bit applications;
    (koala)                           Version 4.1.2 20080704 (Red Hat 4.1.2-55)
                                      Version 4.8.4, 4.9.2
                                  Intel(R) C, C++, Fortran Compilers for
                                  applications running on Intel(R) 64;
                                      Version 15.0.1.133 Build 20141023

    Linux 2.6.32-431.11.2.el6    GNU C (gcc), Fortran (gfortran), C++ (g++)
    #1 SMP x86_64 GNU/Linux       compilers:
    (platypus)                       Version 4.4.7 20120313
                                     Version 4.8.2, Version 4.9.2
                                  PGI C, Fortran, C++ for 64-bit target on
                                  x86-64;
                                      Version 14.10-0
                                  Intel(R) C (icc), C++ (icpc), Fortran (icc)
                                  compilers:
                                     Version 15.0.1.133 Build 20141023

    Linux 2.6.32-431.29.2.el6.ppc64 gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-4)
    #1 SMP ppc64 GNU/Linux        g++ (GCC) 4.4.7 20120313 (Red Hat 4.4.7-4)
    (ostrich)                     GNU Fortran (GCC) 4.4.7 20120313 (Red Hat 4.4.7-4)
                                  IBM XL C/C++ V13.1
                                  IBM XL Fortran V15.1

    SunOS 5.11 32- and 64-bit     Sun C 5.12 SunOS_sparc
    (emu)                         Sun Fortran 95 8.6 SunOS_sparc
                                  Sun C++ 5.12 SunOS_sparc

    Windows 7                     Visual Studio 2008  (cmake)
                                  Visual Studio 2010 w/ Intel Fortran 14 (cmake)
                                  Visual Studio 2012 w/ Intel Fortran 15 (cmake)
                                  Visual Studio 2013 w/ Intel Fortran 15 (cmake)
                                  Cygwin(CYGWIN_NT-6.1 1.7.34(0.285/5/3) gcc(4.9.2) compiler and gfortran)
                                  (cmake and autotools)

    Windows 7 x64                 Visual Studio 2008  (cmake)
                                  Visual Studio 2010 w/ Intel Fortran 14 (cmake)
                                  Visual Studio 2012 w/ Intel Fortran 15 (cmake)
                                  Visual Studio 2013 w/ Intel Fortran 15 (cmake)

    Windows 8.1                   Visual Studio 2012 w/ Intel Fortran 15 (cmake)
                                  Visual Studio 2013 w/ Intel Fortran 15 (cmake)

    Windows 8.1 x64               Visual Studio 2012 w/ Intel Fortran 15 (cmake)
                                  Visual Studio 2013 w/ Intel Fortran 15 (cmake)

    Mac OS X Mt. Lion 10.8.5      Apple clang/clang++ version 5.1 from Xcode 5.1
    64-bit    			  gfortran GNU Fortran (GCC) 4.8.2
    (swallow/kite)                Intel icc/icpc/ifort version 14.0.2

    Mac OS X Mavericks 10.9.5     Apple clang/clang++ version 6.0 from Xcode 6.1.1
    64-bit    			  gfortran GNU Fortran (GCC) 4.8.2
    (wren/quail)                  Intel icc/icpc/ifort version 14.0.2

    Mac OS X Yosemeti 10.10.2     Apple clang/clang++ version 6.0 from Xcode 6.1.1
    64-bit    			  gfortran GNU Fortran (GCC) 4.9.2
    (osx1010dev/osx1010test)      Intel icc/icpc/ifort version 15.0.1


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
SunOS 5.11 32-bit                       n        y/y    n        y    y     y
SunOS 5.11 64-bit                       n        y/y    n        y    y     y
Windows 7                               y        y/y    n        y    y     y
Windows 7 x64                           y        y/y    n        y    y     y
Windows 7 Cygwin                        n        y/y    n        y    y     n
Windows 8.1                             n        y/y    n        y    y     y
Windows 8.1 x64                         n        y/y    n        y    y     y
Mac OS X Mountain Lion 10.8.5 64-bit    n        y/y    n        y    y     y
Mac OS X Mavericks 10.9.5 64-bit        n        y/y    n        y    y     y
Mac OS X Yosemeti 10.10.2 64-bit        n        y/y    n        y    y     y
AIX 6.1 32- and 64-bit                  n        y/n    n        y    y     y
CentOS 5.9 Linux 2.6.18-308 i686 GNU    y        y/y    y        y    y     y
CentOS 5.9 Linux 2.6.18-308 i686 Intel  n        y/y    n        y    y     y
CentOS 5.9 Linux 2.6.18-308 i686 PGI    n        y/y    n        y    y     y
CentOS 5.9 Linux 2.6.18 x86_64 GNU      n        y/y    n        y    y     y
CentOS 5.9 Linux 2.6.18 x86_64 Intel    n        y/y    n        y    y     y
CentOS 6.4 Linux 2.6.32 x86_64 GNU      y        y/y    y        y    y     y
CentOS 6.4 Linux 2.6.32 x86_64 Intel    n        y/y    n        y    y     y
CentOS 6.4 Linux 2.6.32 x86_64 PGI      n        y/y    n        y    y     y
CentOS 7.0 Linux 3.10.0 x86_64 GNU      y        y/y    y        y    y     y
CentOS 7.0 Linux 3.10.0 x86_64 Intel    n        y/y    n        y    y     y
Linux 2.6.32-431.11.2.el6.ppc64         n        y/n    n        y    y     y

Platform                                 Shared  Shared    Shared    Thread-
                                         C libs  F90 libs  C++ libs  safe
SunOS 5.11 32-bit                          y       y         y         y
SunOS 5.11 64-bit                          y       y         y         y
Windows 7                                  y       y         y         y
Windows 7 x64                              y       y         y         y
Windows 7 Cygwin                           n       n         n         y
Windows 8.1                                y       y         y         y
Windows 8.1 x64                            y       y         y         y
Mac OS X Mountain Lion 10.8.5 64-bit       y       n         y         y
Mac OS X Mavericks 10.9.5 64-bit           y       n         y         y
Mac OS X Yosemeti 10.10.2 64-bit           y       n         y         y
AIX 6.1 32- and 64-bit                     y       n         n         y
CentOS 5.9 Linux 2.6.18-308 i686 GNU       y       y         y         y
CentOS 5.9 Linux 2.6.18-308 i686 Intel     y       y         y         n
CentOS 5.9 Linux 2.6.18-308 i686 PGI       y       y         y         n
CentOS 5.9 Linux 2.6.18 x86_64 GNU         y       y         y         y
CentOS 5.9 Linux 2.6.18 x86_64 Intel       y       y         y         n
CentOS 6.4 Linux 2.6.32 x86_64 GNU         y       y         y         n
CentOS 6.4 Linux 2.6.32 x86_64 Intel       y       y         y         n
CentOS 6.4 Linux 2.6.32 x86_64 PGI         y       y         y         n
CentOS 7.0 Linux 3.10.0 x86_64 GNU         y       y         y         n
CentOS 7.0 Linux 3.10.0 x86_64 Intel       y       y         y         n
Linux 2.6.32-431.11.2.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 2.6.18-308.13.1.el5PAE  MPICH mpich 3.1.3 compiled with
    #1 SMP i686 i686 i386             gcc 4.9.2 and gfortran 4.9.2
    (jam)                         g95 (GCC 4.0.3 (g95 0.94!)

    Linux 2.6.18-431.11.2.el6     MPICH mpich 3.1.3 compiled with
    #1 SMP x86_64 GNU/Linux           gcc 4.9.2 and gfortran 4.9.2
    (platypus)                    g95 (GCC 4.0.3 (g95 0.94!)

    FreeBSD 8.2-STABLE i386       gcc 4.5.4 [FreeBSD] 20110526
    (loyalty)                     gcc 4.6.1 20110527
                                  g++ 4.6.1 20110527
                                  gfortran 4.6.1 20110527

    FreeBSD 8.2-STABLE amd64      gcc 4.5.4 [FreeBSD] 20110526
    (freedom)                     gcc 4.6.1 20110527
                                  g++ 4.6.1 20110527
                                  gfortran 4.6.1 20110527

    Debian7.5.0 3.2.0-4-amd64 #1 SMP Debian 3.2.51-1 x86_64 GNU/Linux
                                  gcc (Debian 4.7.2-5) 4.7.2
                                  GNU Fortran (Debian 4.7.2-5) 4.7.2
                                  (cmake and autotools)

    Fedora20 3.15.3-200.fc20.x86_64 #1 SMP x86_64 x86_64 x86_64 GNU/Linux
                                  gcc (GCC) 4.8.3 20140624 (Red Hat 4.8.3-1)
                                  GNU Fortran (GCC) 4.8.3 20140624 (Red Hat 4.8.3-1)
                                  (cmake and autotools)

    SUSE 13.1 3.11.10-17-desktop #1 SMP PREEMPT x86_64 x86_64 x86_64 GNU/Linux
                                  gcc (SUSE Linux) 4.8.1
                                  GNU Fortran (SUSE Linux) 4.8.1
                                  (cmake and autotools)

    Ubuntu 14.04 3.13.0-35-generic #62-Ubuntu SMP x86_64 GNU/Linux
                                  gcc (Ubuntu/Linaro 4.9.1-0ubuntu1) 4.9.1
                                  GNU Fortran (Ubuntu/Linaro 4.9.1-0ubuntu1) 4.9.1
                                  (cmake and autotools)

    hopper.nersc.gov              PrgEnv-gnu/5.2.40
                                  gcc (GCC) 4.9.2 20141030 (Cray Inc.)
                                  GNU Fortran (GCC) 4.9.2 20141030 (Cray Inc.)
                                  g++ (GCC) 4.9.2 20141030 (Cray Inc.)


Known Problems
==============
* On windows platforms in debug configurations, the VFD flush1 tests will fail
  with the split and multi VFD drivers. These tests will display a modal debug
  dialog which must be answered or wait for the test timeout to expire.
  (ADB - 2014/06/23 - HDFFV-8851)

* CLANG compiler with the options -fcatch-undefined-behavior and -ftrapv
  catches some undefined behavior in the alignment algorithm of the macro DETECT_I
  in H5detect.c (Issue 8147).  Since the algorithm is trying to detect the alignment
  of integers, ideally the flag -fcatch-undefined-behavior shouldn't to be used for
  H5detect.c. In the future, we can separate flags for H5detect.c from the rest of
  the library. (SLU - 2013/10/16)

* Make provided by Solaris fails in "make check". Solaris users should use
  gmake to build and install the HDF5 software. (AKC - 2013/10/08 - HDFFV-8534)

* The C++ and FORTRAN bindings are not currently working on FreeBSD with the
  native release 8.2 compilers (4.2.1), but are working with gcc 4.6 from the
  ports (and probably gcc releases after that).
  (QAK - 2012/10/19)

* The following h5dump test case fails in BG/P machines (and potentially other
  machines that use a command script to launch executables):

   h5dump --no-compact-subset -d "AHFINDERDIRECT::ah_centroid_t[0] it=0 tl=0"
     tno-subset.h5

  This is due to the embedded spaces in the dataset name being interpreted
  by the command script launcher as meta-characters, thus passing three
  arguments to h5dump's -d flag. The command passes if run by hand, just
  not via the test script.
  (AKC - 2012/05/03)

* The STDIO VFD does not work on some architectures, possibly due to 32/64
  bit or large file issues.  The basic STDIO VFD test is known to fail on
  64-bit SunOS 5.10 on SPARC when built with -m64 and 32-bit OS X/Darwin
  10.7.0.  The STDIO VFD test has been disabled while we investigate and
  a fix should appear in a future release.
  (DER - 2011/10/14 - HDFFV-8235)

* h5diff can report inconsistent results when comparing datasets of enum type
  that contain invalid values.  This is due to how enum types are handled in
  the library and will be addressed in a future release.
  (DER - 2011/10/14 - HDFFV-7527)

* The links test can fail under the stdio VFD due to some issues with external
  links.  This will be investigated and fixed in a future release.
  (DER - 2011/10/14 - HDFFV-7768)

* After the shared library support was fixed for some bugs, it was discovered
  that "make prefix=XXX install" no longer works for shared libraries. It
  still works correctly for static libraries. Therefore, if you want to
  install the HDF5 shared libraries in a location such as /usr/local/hdf5,
  you need to specify the location via the --prefix option during configure
  time. E.g, ./configure --prefix=/usr/local/hdf5 ...
  (AKC - 2011/05/07 - HDFFV-7583)

* The parallel test, t_shapesame, in testpar/, may run for a long time and may
  be terminated by the alarm signal.  If that happens, one can increase the
  alarm seconds (default is 1200 seconds = 20 minutes) by setting the
  environment variable, $HDF5_ALARM_SECONDS, to a larger value such as 3600
  (60 minutes).  Note that the t_shapesame test may fail in some systems
  (see the "While working on the 1.8.6 release..." problem below).  If
  it does, it will waste more time if $HDF5_ALARM_SECONDS is set
  to a larger value.
  (AKC - 2011/05/07)

* Shared Fortran libraries are not quite working on AIX. While they are
  generated when --enable-shared is specified, the fortran and hl/fortran
  tests fail. the issue. HL and C++ shared libraries should now be
  working as intended, however.
  (MAM - 2011/04/20)

* While working on the 1.8.6 release of HDF5, a bug was discovered that can
  occur when reading from a dataset in parallel shortly after it has been
  written to collectively. The issue was exposed by a new test in the parallel
  HDF5 test suite, but had existed before that. We believe the problem lies with
  certain MPI implementations and/or file systems.

  We have provided a pure MPI test program, as well as a standalone HDF5
  program, that can be used to determine if this is an issue on your system.
  They should be run across multiple nodes with a varying number of processes.
  These programs can be found at:
  http://www.hdfgroup.org/ftp/HDF5/examples/known_problems/
  (NAF - 2011/01/19)

* All the VFL drivers aren't backward compatible.  In H5FDpublic.h, the
  structure H5FD_class_t changed in 1.8.  There is new parameter added to
  get_eoa and set_eoa callback functions.  A new callback function
  get_type_map was added in.  The public function H5FDrealloc was taken
  out in 1.8.  The problem only happens when users define their own driver
  for 1.6 and try to plug in 1.8 library.  Because there's only one user
  complaining about it, we (Elena, Quincey, and I) decided to leave it as
  it is (see bug report #1279).  Quincey will make a plan for 1.10.
  (SLU - 2010/02/02)

* The --enable-static-exec configure flag will only statically link libraries
  if the static version of that library is present. If only the shared version
  of a library exists (i.e., most system libraries on Solaris, AIX, and Mac,
  for example, only have shared versions), the flag should still result in a
  successful compilation, but note that the installed executables will not be
  fully static. Thus, the only guarantee on these systems is that the
  executable is statically linked with just the HDF5 library.
  (MAM - 2009/11/04)

* A dataset created or rewritten with a v1.6.3 library or after cannot be read
  with the v1.6.2 library or before when the Fletcher32 EDC filter is enabled.
  There was a bug in the calculation of the Fletcher32 checksum in the
  library before v1.6.3; the checksum value was not consistent between big-
  endian and little-endian systems.  This bug was fixed in Release 1.6.3.
  However, after fixing the bug, the checksum value was no longer the same as
  before on little-endian system.  Library releases after 1.6.4 can still read
  datasets created or rewritten with an HDF5 library of v1.6.2 or before.
  (SLU - 2005/06/30)