path: root/release_docs/RELEASE.txt

HDF5 version 1.8.18-snap1 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
    -------------
    - Cmakehdf5: added ability to run multiple make commands.
      Added option --njobs to specific up to homw many jobs to launch during
      build (cmamke) and testing (ctest).
      (AKC, 2015/12/13, HDFFV-9612)

    - Cmakehdf5: added --with-szlib to support szip library support; and
      --enable/disable-verbose to display all cmake process output.
      (AKC, 2015/11/16, HDFFV-8932 and DAILYTEST-195)

    - CMake minimum is now 3.1.0. (ADB 2015/11/14)

    - Large file system (LFS) support has changed in the autotools

      * We assume that fseeko and ftello exist.

      * The *64 I/O functions and types are no longer explicitly used.
        We now rely on a mapping provided by _FILE_OFFSET_BITS (or its
        equivalent).

      * _LARGEFILE(64)_SOURCE is no longer exposed via AM_CPPFLAGS.

      (DER, 2016/03/29, HDFFV-9626)


    Library
    -------
    - New API calls that determine the search path for dataset external
      storage.

      H5Pset/get_efile_prefix() API calls were added to the library. These
      functions give control over the search path for dataset external storage
      that has been configured with H5Pset_external().

      Additionally, the HDF5_EXTFILE_PREFIX environment variable can be
      used to control the search path.

      (DER, 2016/04/20, HDFFV-8740)

    Parallel Library
    ----------------
    - None

    Tools
    -----
    - None


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

    C Packet Table API
    ------------------
    - Replacement of a Public Function with H5PTcreate

      The existing function H5PTcreate_fl limits applications so they
      can use the deflate compression only. The public function
      H5PTcreate has been added to replace H5PTcreate_fl. H5PTcreate
      takes a property list identifier to provide flexibility on
      creation properties.

      (BMR - 2016/04/25, HDFFV-8623)

    - New Public Functions: H5PTget_dataset and H5PTget_type

      Two accessor functions have been added. H5PTget_dataset returns
      the identifier of the dataset associated with the packet table,
      and H5PTget_type returns the identifier of the datatype used by
      the packet table.

      (BMR, 2016/04/25, HDFFV-8623)

    - Regarding #ifdef VLPT_REMOVED

      The #ifdef VLPT_REMOVED blocks have been removed from the packet
      table (PT) library source except for the following functions:
        + H5PTis_varlen() has been made available again
        + H5PTfree_vlen_readbuff() is now H5PTfree_vlen_buff()

      (BMR - 2016/04/25, HDFFV-442)

    C++ Packet Table API
    --------------------
    - New Constructor in FL_PacketTable

      An overloaded constructor has been added to FL_PacketTable and
      takes a property list identifier to provide flexibility on
      creation properties, such as compression.

      FL_PacketTable(hid_t fileID, const char* name, hid_t dtypeID,
                       hsize_t chunkSize = 0, hid_t plistID = H5P_DEFAULT)

      (BMR - 2016/04/25, HDFFV-8623)

    - New Member Functions in PacketTable

      Two accessor wrappers are added to class PacketTable.

      PacketTable::GetDataset() returns the identifier of the dataset
                    associated with the packet table
      PacketTable::GetDatatype() returns the identifier of the datatype
                that the packet table uses.

      (BMR - 2016/04/25, HDFFV-8623)

    - Member Functions with "char*" as an Argument

      Overloaded functions were added to provide the "const char*"
      argument; the existing version will be deprecated in future
      releases.

      (BMR - 2016/04/25, HDFFV-8623)

    - Regarding #ifdef VLPT_REMOVED

      The #ifdef VLPT_REMOVED blocks have been removed from the packet
      table library source code except for the following functions:
        + VL_PacketTable::IsVariableLength() was moved to PacketTable
        + VL_PacketTable::FreeReadBuff() is now PacketTable::FreeBuff()

      (BMR - 2016/04/25, HDFFV-442)



    Fortran API
    -----------
    - None


    C++ API
    -------
    - New Member Function in DSetCreatPropList

      DSetCreatPropList::setNbit() was added to setup N-bit compression for
      a dataset.

      (BMR, 2016/04/25)

    - New Overloaded "const" Member Functions in ArrayType

      The two following functions are added:
    ArrayType::getArrayNDims() const
    ArrayType::getArrayDims() const
      to provide const version and the non-const version are marked deprecated.
      In-memory array information, ArrayType::rank and ArrayType::dimensions,
      are removed.  This is implementation detail and should not affect
      applications.

      (BMR, 2016/04/25, HDFFV-9725)


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

Bug Fixes since HDF5-1.8.16
===========================

    Configuration
    -------------
    - Updated Linux language level flags to match the Autotools. Removed
      Linux-specific flags from OS X.

      An addition to the flags simply being out of sync with the Autotools,
      the Linux flags were used on OS X builds which led to symbols not being
      found. Although this was non-fatal and compilation continued (implicit
      definitions were used by the compiler and the symbols resolved at link
      time), a large number of warnings were raised.

      Linux changes:

      * CHANGED:    _POSIX_C_SOURCE (from 199605 to 200112L)
      * ADDED:      _GNU_SOURCE
      * REMOVED:    _BSD_SOURCE
      * REMOVED:    _DEFAULT_SOURCE

      (DER, 2015/12/08, HDFFV-9627)

    - The --enable-clear-file-buffers configure option was non-functional so
      the feature was always enabled (its default value).

      Regardless of the configure flag, the setting was always enabled when
      the autotools were used to configure HDF5. This was due to the "no"
      option being processed after the "*" option in configure.ac so "*"
      matched first. CMake was unaffected.

      The option now works correctly.

      NOTE that builders are always advised to leave this option enabled.
      When disabled, buffers that are written to disk may contain the
      memory's previous contents, which may include secure information.
      The performance overhead of the feature (a single memset call per
      allocation) is minimal.

      (DER, 2016/02/03, HDFFV-9676)

    Library
    -------
    - Fixed some format string warnings that prevent compiling with
      -Werror=format-security on gcc.

      These only appeared in error messages and would not cause problems
      under normal operation.

      (DER, 2016/01/13, HDFFV-9640)

    - Fixed a library segmentation fault when accessing a corrupted
      file provided by a user.

      (MSC, 2016/02/19, HDFFV-9670)

    Parallel Library
    ----------------
    - None

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

    Tools
    -----
    - h5dump subsetting fixed for dims greater then two.

      When a dataset has more then two dimensions, subsetting would incorrectly
      calculate the data that needed to be displayed.
      Added in block and stride calculation that account for dimensions greater
      then two.  NOTE: lines that have line breaks inserted because of display
      length calculations, may have index info that is incorrect until the next
      dimension break.

      (ADB, 2016/03/07, HDFFV-9698)

    - h5dump issue with argument segfault.

      When an argument with an optional value was at the end of the command line
      with a value, h5dump would crash. Reworked check for remaining arguments.

      (ADB, 2016/03/07, HDFFV-9570, HDFFV-9684)

    - h5dump issue with default fill value.

      Added all default cases of fill value to display of fill value.

      (ADB, 2016/03/07, HDFFV-9241)

    - Clarified usage of -O F option in h5dump utility help.

      (ADB, 2016/03/07, HDFFV-9066)

    - h5dump issue with double free fault.

      Added check for filename not null before calling free().

      (ADB, 2016/01/27, HDFFV-9639)

    - VS2015 release changed how timezone was handled.

      Created a function, HDget_timezone, in H5system.c. Replaced timezone variable
      usage with function call.

      (ADB, 2015/11/02, HDFFV-9550)

    Fortran API
    -----------
    - None

    C++ API
    -------
    - Removal of Obsolete Methods

      The overloaded methods which had parameters that should be const but were       not are removed.

      (BMR, 2016/01/13, User's report)


    High-Level APIs:
    ---------------
    - Fixed Memory Leak in Packet Table API

      Applied user's patch to fix memory leak in the creation of a packet table.

      (BMR, 2016/04/25, HDFFV-9700)


    Fortran High-Level APIs:
    ------------------------
    - None


    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 2.6.32-573.3.1.el6    GNU C (gcc), Fortran (gfortran), C++ (g++)
    #1 SMP x86_64 GNU/Linux       compilers:
    (platypus)                       Version 4.4.7 20120313
                                     Version 4.8.4, Version 5.2.0
                                  PGI C, Fortran, C++ for 64-bit target on
                                  x86-64;
                                      Version 15.7-0
                                  Intel(R) C (icc), C++ (icpc), Fortran (icc)
                                  compilers:
                                     Version 15.0.3.187 Build 20150407
                                  MPICH 3.1.4 compiled with GCC 4.9.3

    Linux 2.6.32-504.8.1.el6.ppc64 gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-11)
    #1 SMP ppc64 GNU/Linux        g++ (GCC) 4.4.7 20120313 (Red Hat 4.4.7-11)
    (ostrich)                     GNU Fortran (GCC) 4.4.7 20120313 (Red Hat 4.4.7-11)
                                  IBM XL C/C++ V13.1
                                  IBM XL Fortran V15.1

    Linux 3.10.0-229.14.1.el7   GNU C (gcc), Fortran (gfortran), C++ (g++)
    #1 SMP x86_64 GNU/Linux       compilers:
    (kituo/moohan)                  Version 4.8.3 20140911 (Red Hat 4.8.3-9)
                                    Version 5.2.0
                                  Intel(R) C (icc), C++ (icpc), Fortran (icc)
                                  compilers:
                                     Version 15.0.3.187 Build 20150407
                                  MPICH 3.1.4 compiled with GCC 4.9.3

    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 2012 w/ Intel Fortran 15 (cmake)
                                  Visual Studio 2013 w/ Intel Fortran 15 (cmake)
                                  Visual Studio 2015  (cmake)
                                  Cygwin(CYGWIN_NT-6.1 2.2.1(0.289/5/3) gcc(4.9.3) compiler and gfortran)
                                  (cmake and autotools)

    Windows 7 x64                 Visual Studio 2012 w/ Intel Fortran 15 (cmake)
                                  Visual Studio 2013 w/ Intel Fortran 15 (cmake)
                                  Visual Studio 2015  (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 15.0.3

    Mac OS X Mavericks 10.9.5     Apple clang/clang++ version 6.0 from Xcode 6.2.0
    64-bit                        gfortran GNU Fortran (GCC) 4.9.2
    (wren/quail)                  Intel icc/icpc/ifort version 15.0.3

    Mac OS X Yosemite 10.10.5     Apple clang/clang++ version 6.0 from Xcode 7.0.0
    64-bit                        gfortran GNU Fortran (GCC) 4.9.2
    (osx1010dev/osx1010test)      Intel icc/icpc/ifort version 15.0.3


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 10.10.5 64-bit        n        y/y    n        y    y     y
AIX 6.1 32- and 64-bit                  n        y/n    n        y    y     y
CentOS 6.7 Linux 2.6.32 x86_64 GNU      y        y/y    y        y    y     y
CentOS 6.7 Linux 2.6.32 x86_64 Intel    n        y/y    n        y    y     y
CentOS 6.7 Linux 2.6.32 x86_64 PGI      n        y/y    n        y    y     y
CentOS 7.1 Linux 3.10.0 x86_64 GNU      y        y/y    y        y    y     y
CentOS 7.1 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 10.10.5 64-bit           y       n         y         y
AIX 6.1 32- and 64-bit                     y       n         n         y
CentOS 6.7 Linux 2.6.32 x86_64 GNU         y       y         y         y
CentOS 6.7 Linux 2.6.32 x86_64 Intel       y       y         y         y
CentOS 6.7 Linux 2.6.32 x86_64 PGI         y       y         y         y
CentOS 7.1 Linux 3.10.0 x86_64 GNU         y       y         y         y
CentOS 7.1 Linux 3.10.0 x86_64 Intel       y       y         y         y
Linux 2.6.32-431.11.2.el6.ppc64            y       y         y         y

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 2.6.18-431.11.2.el6     g95 (GCC 4.0.3 (g95 0.94!)
    #1 SMP x86_64 GNU/Linux
    (platypus)

    Mac OS X El Capitan 10.11     Apple clang/clang++ version 7.0.0 from Xcode 7.0.1
    64-bit                        gfortran GNU Fortran (GCC) 5.2.0
    (VM)

    Windows 7                     Visual Studio 2008  (cmake)

    Windows 7 x64                 Visual Studio 2008  (cmake)

    Windows 10                    Visual Studio 2013 w/ Intel Fortran 15 (cmake)

    Windows 10 x64                Visual Studio 2013 w/ Intel Fortran 15 (cmake)

    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)