VFD SWMR: normalization with develop (#1472)

Much normalization with develop. Still needs tools changes wrt VFD plugins.

1 files changed, 1758 insertions, 0 deletions

diff --git a/release_docs/HISTORY-1_13.txt b/release_docs/HISTORY-1_13.txt
new file mode 100644
index 0000000..06be75b
--- /dev/null
+++ b/release_docs/HISTORY-1_13.txt
@@ -0,0 +1,1758 @@
+HDF5 History
+============
+
+This file contains development history of the HDF5 1.13 releases from
+the develop branch
+
+01.      Release Information for hdf5-1.13.0
+
+[Search on the string '%%%%' for section breaks of each release.]
+
+%%%%1.13.0%%%%
+
+HDF5 version 1.13.0 released on 2021-12-01
+================================================================================
+
+
+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 HDF5-1.13.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
+- New platforms, languages and compilers tested
+- Bug Fixes since HDF5-1.12.0
+- Platforms Tested
+- Known Problems
+- CMake vs. Autotools installations
+
+
+New Features
+============
+
+    Configuration:
+    -------------
+    - Added new configure option to support building parallel tools.
+      See Tools below (autotools - CMake):
+            --enable-parallel-tools      HDF5_BUILD_PARALLEL_TOOLS
+
+      (RAW - 2021/10/25)
+
+    - Added new configure options to enable dimension scales APIs (H5DS*) to
+      use new object references with the native VOL connector (aka native HDF5
+      library). New references are always used for non-native terminal VOL
+      connectors (e.g., DAOS).
+
+      Autotools   --enable-dimension-scales-with-new-ref
+      CMake       HDF5_DIMENSION_SCALES_NEW_REF=ON
+
+      (EIP - 2021/10/25, HDFFV-11180)
+
+    - 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)
+
+    - Added new option to control the build of High-Level tools
+      that default ON/enabled.
+
+      Add configure options (autotools - CMake):
+            --enable-hltools       HDF5_BUILD_HL_TOOLS
+
+      Disabling this option prevents building the gif tool which
+      contains the following CVEs:
+          HDFFV-10592 CVE-2018-17433
+          HDFFV-10593 CVE-2018-17436
+          HDFFV-11048 CVE-2020-10809
+
+      (ADB - 2021/09/16, HDFFV-11266)
+
+    - Adds C++ Autotools configuration file for Intel
+
+      * Checks for icpc as the compiler
+      * Sets std=c++11
+      * Copies most non-warning flags from intel-flags
+
+      (DER - 2021/06/02)
+
+    - Adds C++ Autotools configuration file for PGI
+
+      * Checks for pgc++ as the compiler name (was: pgCC)
+      * Sets -std=c++11
+      * Other options basically match new C options (below)
+
+      (DER - 2021/06/02)
+
+    - Updates PGI C options
+
+      * -Minform set to warn (was: inform) to suppress spurious messages
+      * Sets -gopt -O2 as debug options
+      * Sets -O4 as 'high optimization' option
+      * Sets -O0 as 'no optimization' option
+      * Removes specific settings for PGI 9 and 10
+
+      (DER - 2021/06/02)
+
+    - A C++11-compliant compiler is now required to build the C++ wrappers
+
+      CMAKE_CXX_STANDARD is now set to 11 when building with CMake and
+      -std=c++11 is added when building with clang/gcc via the Autotools.
+
+      (DER - 2021/05/27)
+
+    - CMake will now run the shell script tests in test/ by default
+
+      The test directory includes several shell script tests that previously
+      were not run by CMake. These are now run by default. TEST_SHELL_SCRIPTS
+      has been set to ON and SH_PROGRAM has been set to bash (some test
+      scripts use bash-isms). Platforms without bash (e.g., Windows) will
+      ignore the script tests.
+
+      (DER - 2021/05/23)
+
+    - Removed unused HDF5_ENABLE_HSIZET option from CMake
+
+      This has been unused for some time and has no effect.
+
+      (DER - 2021/05/23)
+
+    - CMake no longer builds the C++ library by default
+
+      HDF5_BUILD_CPP_LIB now defaults to OFF, which is in line with the
+      Autotools build defaults.
+
+      (DER - 2021/04/20)
+
+    - Removal of pre-VS2015 work-arounds
+
+      HDF5 now requires Visual Studio 2015 or greater, so old work-around
+      code and definitions have been removed, including:
+
+      * <inttypes.h>
+      * snprintf and vsnprintf
+      * llround, llroundf, lround, lroundf, round, roundf
+      * strtoll and strtoull
+      * va_copy
+      * struct timespec
+
+      (DER - 2021/03/22)
+
+    - Add CMake variable HDF5_LIB_INFIX
+
+      This infix is added to all library names after 'hdf5'.
+      e.g. the infix '_openmpi' results in the library name 'libhdf5_openmpi.so'
+      This name is used in packages on debian based systems.
+      (see https://packages.debian.org/jessie/amd64/libhdf5-openmpi-8/filelist)
+
+      (barcode - 2021/03/22)
+
+    - On macOS, Universal Binaries can now be built, allowing native execution on
+      both Intel and Apple Silicon (ARM) based Macs.
+
+      To do so, set CMAKE_OSX_ARCHITECTURES="x86_64;arm64"
+
+      (SAM - 2021/02/07, github-311)
+
+    - Added a configure-time option to control certain compiler warnings
+      diagnostics
+
+      A new configure-time option was added that allows some compiler warnings
+      diagnostics to have the default operation. This is mainly intended for
+      library developers and currently only works for gcc 10 and above. The
+      diagnostics flags apply to C, C++ and Fortran compilers and will appear
+      in "H5 C Flags", H5 C++ Flags" and H5 Fortran Flags, respectively. They
+      will NOT be exported to h5cc, etc.
+
+      The default is OFF, which will disable the warnings URL and color attributes
+      for the warnings output. ON will not add the flags and allow default behavior.
+
+      Autotools:    --enable-diags
+
+      CMake:        HDF5_ENABLE_BUILD_DIAGS
+
+      (ADB - 2021/02/05, HDFFV-11213)
+
+    - CMake option to build the HDF filter plugins project as an external project
+
+      The HDF filter plugins project is a collection of registered compression
+      filters that can be dynamically loaded when needed to access data stored
+      in a hdf5 file. This CMake-only option allows the plugins to be built and
+      distributed with the hdf5 library and tools. Like the options for szip and
+      zlib, either a tgz file or a git repository can be specified for the source.
+
+      The option was refactored to use the CMake FetchContent process. This allows
+      more control over the filter targets, but required external project command
+      options to be moved to a CMake include file, HDF5PluginCache.cmake. Also
+      enabled the filter examples to be used as tests for operation of the
+      filter plugins.
+
+      (ADB - 2020/12/10, OESS-98)
+
+    - FreeBSD Autotools configuration now defaults to 'cc' and 'c++' compilers
+
+      On FreeBSD, the autotools defaulted to 'gcc' as the C compiler and did
+      not process C++ options. Since FreeBSD 10, the default compiler has
+      been clang (via 'cc').
+
+      The default compilers have been set to 'cc' for C and 'c++' for C++,
+      which will pick up clang and clang++ respectively on FreeBSD 10+.
+      Additionally, clang options are now set correctly for both C and C++
+      and g++ options will now be set if that compiler is being used (an
+      omission from the former functionality).
+
+      (DER - 2020/11/28, HDFFV-11193)
+
+    - Fixed POSIX problems when building w/ gcc on Solaris
+
+      When building on Solaris using gcc, the POSIX symbols were not
+      being set correctly, which could lead to issues like clock_gettime()
+      not being found.
+
+      The standard is now set to gnu99 when building with gcc on Solaris,
+      which allows POSIX things to be #defined and linked correctly. This
+      differs slightly from the gcc norm, where we set the standard to c99
+      and manually set POSIX #define symbols.
+
+      (DER - 2020/11/25, HDFFV-11191)
+
+    - Added a configure-time option to consider certain compiler warnings
+      as errors
+
+      A new configure-time option was added that converts some compiler warnings
+      to errors. This is mainly intended for library developers and currently
+      only works for gcc and clang. The warnings that are considered errors
+      will appear in the generated libhdf5.settings file. These warnings apply
+      to C and C++ code and will appear in "H5 C Flags" and H5 C++ Flags",
+      respectively. They will NOT be exported to h5cc, etc.
+
+      The default is OFF. Building with this option may fail when compiling
+      on operating systems and with compiler versions not commonly used by
+      the library developers. Compilation may also fail when headers not
+      under the control of the library developers (e.g., mpi.h, hdfs.h) raise
+      warnings.
+
+      Autotools:    --enable-warnings-as-errors
+
+      CMake:        HDF5_ENABLE_WARNINGS_AS_ERRORS
+
+      (DER - 2020/11/23, HDFFV-11189)
+
+    - Autotools and CMake target added to produce doxygen generated documentation
+
+      The default is OFF or disabled.
+      Autoconf option is '--enable-doxygen'
+        autotools make target is 'doxygen' and will build all doxygen targets
+      CMake configure option is 'HDF5_BUILD_DOC'.
+        CMake target is 'doxygen' for all available doxygen targets
+        CMake target is 'hdf5lib_doc' for the src subdirectory
+
+      (ADB - 2020/11/03)
+
+    - CMake option to use MSVC naming conventions with MinGW
+
+      HDF5_MSVC_NAMING_CONVENTION option enable to use MSVC naming conventions
+      when using a MinGW toolchain
+
+      (xan - 2020/10/30)
+
+    - CMake option to statically link gcc libs with MinGW
+
+      HDF5_MINGW_STATIC_GCC_LIBS allows to statically link libg/libstdc++
+      with the MinGW toolchain
+
+      (xan - 2020/10/30)
+
+    - CMake option to build the HDF filter plugins project as an external project
+
+      The HDF filter plugins project is a collection of registered compression
+      filters that can be dynamically loaded when needed to access data stored
+      in a hdf5 file. This CMake-only option allows the plugins to be built and
+      distributed with the hdf5 library and tools. Like the options for szip and
+      zlib, either a tgz file or a git repository can be specified for the source.
+
+      The necessary options are (see the INSTALL_CMake.txt file):
+        HDF5_ENABLE_PLUGIN_SUPPORT
+        PLUGIN_TGZ_NAME or PLUGIN_GIT_URL
+      There are more options necessary for various filters and the plugin project
+      documents should be referenced.
+
+      (ADB - 2020/09/27, OESS-98)
+
+    - Added CMake option to format source files
+
+      HDF5_ENABLE_FORMATTERS option will enable creation of targets using the
+      pattern - HDF5_*_SRC_FORMAT - where * corresponds to the source folder
+      or tool folder. All sources can be formatted by executing the format target;
+      make format
+
+      (ADB - 2020/08/24)
+
+    - Add file locking configure and CMake options
+
+      HDF5 1.10.0 introduced a file locking scheme, primarily to help
+      enforce SWMR setup. Formerly, the only user-level control of the scheme
+      was via the HDF5_USE_FILE_LOCKING environment variable.
+
+      This change introduces configure-time options that control whether
+      or not file locking will be used and whether or not the library
+      ignores errors when locking has been disabled on the file system
+      (useful on some HPC Lustre installations).
+
+      In both the Autotools and CMake, the settings have the effect of changing
+      the default property list settings (see the H5Pset/get_file_locking()
+      entry, below).
+
+      The yes/no/best-effort file locking configure setting has also been
+      added to the libhdf5.settings file.
+
+      Autotools:
+
+        An --enable-file-locking=(yes|no|best-effort) option has been added.
+
+        yes:          Use file locking.
+        no:           Do not use file locking.
+        best-effort:  Use file locking and ignore "disabled" errors.
+
+      CMake:
+
+        Two self-explanatory options have been added:
+
+        HDF5_USE_FILE_LOCKING
+        HDF5_IGNORE_DISABLED_FILE_LOCKS
+
+        Setting both of these to ON is the equivalent to the Autotools'
+        best-effort setting.
+
+      NOTE:
+      The precedence order of the various file locking control mechanisms is:
+
+        1) HDF5_USE_FILE_LOCKING environment variable (highest)
+
+        2) H5Pset_file_locking()
+
+        3) configure/CMake options (which set the property list defaults)
+
+        4) library defaults (currently best-effort)
+
+      (DER - 2020/07/30, HDFFV-11092)
+
+    - CMake option to link the generated Fortran MOD files into the include
+      directory.
+
+      The Fortran generation of MOD files by a Fortran compile can produce
+      different binary files between SHARED and STATIC compiles with different
+      compilers and/or different platforms. Note that it has been found that
+      different versions of Fortran compilers will produce incompatible MOD
+      files. Currently, CMake will locate these MOD files in subfolders of
+      the include directory and add that path to the Fortran library target
+      in the CMake config file, which can be used by the CMake find library
+      process. For other build systems using the binary from a CMake install,
+      a new CMake configuration can be used to copy the pre-chosen version
+      of the Fortran MOD files into the install include directory.
+
+      The default will depend on the configuration of
+      BUILD_STATIC_LIBS and BUILD_SHARED_LIBS:
+          YES                   YES         Default to SHARED
+          YES                   NO          Default to STATIC
+          NO                    YES         Default to SHARED
+          NO                    NO          Default to SHARED
+      The defaults can be overridden by setting the config option
+          HDF5_INSTALL_MOD_FORTRAN to one of NO, SHARED, or STATIC
+
+      (ADB - 2020/07/09, HDFFV-11116)
+
+    - CMake option to use AEC (open source SZip) library instead of SZip
+
+      The open source AEC library is a replacement library for SZip. In
+      order to use it for hdf5 the libaec CMake source was changed to add
+      "-fPIC" and exclude test files. Autotools does not build the
+      compression libraries within hdf5 builds. New option USE_LIBAEC is
+      required to compensate for the different files produced by AEC build.
+
+      (ADB - 2020/04/22, OESS-65)
+
+    - CMake ConfigureChecks.cmake file now uses CHECK_STRUCT_HAS_MEMBER
+
+      Some handcrafted tests in HDFTests.c has been removed and the CMake
+      CHECK_STRUCT_HAS_MEMBER module has been used.
+
+      (ADB - 2020/03/24, TRILAB-24)
+
+    - Both build systems use same set of warnings flags
+
+      GNU C, C++ and gfortran warnings flags were moved to files in a config
+      sub-folder named gnu-warnings. Flags that only are available for a specific
+      version of the compiler are in files named with that version.
+      Clang C warnings flags were moved to files in a config sub-folder
+      named clang-warnings.
+      Intel C, Fortran warnings flags were moved to files in a config sub-folder
+      named intel-warnings.
+
+      There are flags in named "error-xxx" files with warnings that may
+      be promoted to errors. Some source files may still need fixes.
+
+      There are also pairs of files named "developer-xxx" and "no-developer-xxx"
+      that are chosen by the CMake option:HDF5_ENABLE_DEV_WARNINGS or the
+      configure option:--enable-developer-warnings.
+
+      In addition, CMake no longer applies these warnings for examples.
+
+      (ADB - 2020/03/24, TRILAB-192)
+
+    - Added test script for file size compare
+
+      If CMake minimum version is at least 3.14, the fileCompareTest.cmake
+      script will compare file sizes.
+
+      (ADB - 2020/02/24, HDFFV-11036)
+
+    - Update CMake minimum version to 3.12
+
+      Updated CMake minimum version to 3.12 and added version checks
+      for Windows features.
+
+      (ADB - 2020/02/05, TRILABS-142)
+
+    - Fixed CMake include properties for Fortran libraries
+
+      Corrected the library properties for Fortran to use the
+      correct path for the Fortran module files.
+
+      (ADB - 2020/02/04, HDFFV-11012)
+
+    - Added common warnings files for gnu and intel
+
+      Added warnings files to use one common set of flags
+      during configure for both autotools and CMake build
+      systems. The initial implementation only affects a
+      general set of flags for gnu and intel compilers.
+
+      (ADB - 2020/01/17)
+
+    - Added new options to CMake for control of testing
+
+      Added CMake options (default ON);
+        HDF5_TEST_SERIAL AND/OR HDF5_TEST_PARALLEL
+        combined with:
+          HDF5_TEST_TOOLS
+          HDF5_TEST_EXAMPLES
+          HDF5_TEST_SWMR
+          HDF5_TEST_FORTRAN
+          HDF5_TEST_CPP
+          HDF5_TEST_JAVA
+
+      (ADB - 2020/01/15, HDFFV-11001)
+
+    - Added Clang sanitizers to CMake for analyzer support if compiler is clang.
+
+      Added CMake code and files to execute the Clang sanitizers if
+      HDF5_ENABLE_SANITIZERS is enabled and the USE_SANITIZER option
+      is set to one of the following:
+        Address
+        Memory
+        MemoryWithOrigins
+        Undefined
+        Thread
+        Leak
+        'Address;Undefined'
+
+      (ADB - 2019/12/12, TRILAB-135)
+
+    - Update CMake for VS2019 support
+
+      CMake added support for VS2019 in version 3.15. Changes to the CMake
+      generator setting required changes to scripts. Also updated version
+      references in CMake files as necessary.
+
+      (ADB - 2019/11/18, HDFFV-10962)
+
+    - Update CMake options to match new autotools options
+
+      Add configure options (autotools - CMake):
+        enable-asserts       HDF5_ENABLE_ASSERTS
+        enable-symbols       HDF5_ENABLE_SYMBOLS
+        enable-profiling     HDF5_ENABLE_PROFILING
+        enable-optimization  HDF5_ENABLE_OPTIMIZATION
+      In addition NDEBUG is no longer forced defined and relies on the CMake
+      process.
+
+      (ADB - 2019/10/07, HDFFV-100901, HDFFV-10637, TRILAB-97)
+
+
+    Library:
+    --------
+    - Adds new file driver-level memory copy operation for
+      "ctl" callback and updates compact dataset I/O routines
+      to utilize it
+
+      When accessing an HDF5 file with a file driver that uses
+      memory allocated in special ways (e.g., without standard
+      library's `malloc`), a crash could be observed when HDF5
+      tries to perform `memcpy` operations on such a memory
+      region.
+
+      These changes add a new H5FD_FEAT_MEMMANAGE VFD feature
+      flag, which, if specified as supported by a VFD, will
+      inform HDF5 that the VFD either uses special memory
+      management routines or wishes to perform memory management
+      in a specific way. Therefore, this flag instructs HDF5 to
+      ask the file driver to perform memory management for
+      certain operations.
+
+      These changes also introduce a new "ctl" callback
+      operation identified by the H5FD_CTL__MEM_COPY op code.
+      This operation simply asks a VFD to perform a memory copy.
+      The arguments to this operation are passed to the "ctl"
+      callback's "input" parameter as a pointer to a struct
+      defined as:
+
+        struct H5FD_ctl_memcpy_args_t {
+          void *      dstbuf;  /**< Destination buffer */
+          hsize_t     dst_off; /**< Offset within destination buffer */
+          const void *srcbuf;  /**< Source buffer */
+          hsize_t     src_off; /**< Offset within source buffer */
+          size_t      len;     /**< Length of data to copy from source buffer */
+        } H5FD_ctl_memcpy_args_t;
+
+      Further, HDF5's compact dataset I/O routines were
+      identified as a problematic area that could cause a crash
+      for VFDs that make use of special memory management. Those
+      I/O routines were therefore updated to make use of this new
+      "ctl" callback operation in order to ask the underlying
+      file driver to correctly handle memory copies.
+
+      (JTH - 2021/09/28)
+
+    - Adds new "ctl" callback to VFD H5FD_class_t structure
+      with the following prototype:
+
+        herr_t (*ctl)(H5FD_t *file, uint64_t op_code,
+                      uint64_t flags, const void *input,
+                      void **output);
+
+      This newly-added "ctl" callback allows Virtual File
+      Drivers to intercept and handle arbitrary operations
+      identified by an operation code. Its parameters are
+      as follows:
+
+        `file` [in] - A pointer to the file to be operated on
+        `op_code` [in] - The operation code identifying the
+                         operation to be performed
+        `flags` [in] - Flags governing the behavior of the
+                       operation performed (see H5FDpublic.h
+                       for a list of valid flags)
+        `input` [in] - A pointer to arguments passed to the
+                       VFD performing the operation
+        `output` [out] - A pointer for the receiving VFD to
+                         use for output from the operation
+
+      (JRM - 2021/08/16)
+
+    - Change how the release part of version, in major.minor.release is checked
+      for compatibility
+
+      The HDF5 library uses a function, H5check_version, to check that
+      the version defined in the header files, which is used to compile an
+      application is compatible with the version codified in the library, which
+      the application loads at runtime. This previously required an exact match
+      or the library would print a warning, dump the build settings and then
+      abort or continue. An environment variable controlled the logic.
+
+      Now the function first checks that the library release version, in
+      major.minor.release, is not older than the version in the headers.
+      Secondly, if the release version is different, it checks if either
+      the library version or the header version is in the exception list, in
+      which case the release part of version, in major.minor.release, must
+      be exact. An environment variable still controls the logic.
+
+      (ADB - 2021/07/27)
+
+    - gcc warning suppression macros were moved out of H5public.h
+
+      The HDF5 library uses a set of macros to suppress warnings on gcc.
+      These warnings were originally located in H5public.h so that the
+      multi VFD (which only uses public headers) could also make use of them
+      but internal macros should not be publicly exposed like this.
+
+      These macros have now been moved to H5private.h. Pending future multi
+      VFD refactoring, the macros have been duplicated in H5FDmulti.c to
+      suppress the format string warnings there.
+
+      (DER - 2021/06/03)
+
+    - H5Gcreate1() now rejects size_hint parameters larger than UINT32_MAX
+
+      The size_hint value is ultimately stored in a uint32_t struct field,
+      so specifying a value larger than this on a 64-bit machine can cause
+      undefined behavior including crashing the system.
+
+      The documentation for this API call was also incorrect, stating that
+      passing a negative value would cause the library to use a default
+      value. Instead, passing a "negative" value actually passes a very large
+      value, which is probably not what the user intends and can cause
+      crashes on 64-bit systems.
+
+      The Doxygen documentation has been updated and passing values larger
+      than UINT32_MAX for size_hint will now produce a normal HDF5 error.
+
+      (DER - 2021/04/29, HDFFV-11241)
+
+
+    - H5Pset_fapl_log() no longer crashes when passed an invalid fapl ID
+
+      When passed an invalid fapl ID, H5Pset_fapl_log() would usually
+      segfault when attempting to free an uninitialized pointer in the error
+      handling code. This behavior is more common in release builds or
+      when the memory sanitization checks were not selected as a build
+      option.
+
+      The pointer is now correctly initialized and the API call now
+      produces a normal HDF5 error when fed an invalid fapl ID.
+
+      (DER - 2021/04/28, HDFFV-11240)
+
+    - Fixes a segfault when H5Pset_mdc_log_options() is called multiple times
+
+      The call incorrectly attempts to free an internal copy of the previous
+      log location string, which causes a segfault. This only happens
+      when the call is invoked multiple times on the same property list.
+      On the first call to a given fapl, the log location is set to NULL so
+      the segfault does not occur.
+
+      The string is now handled properly and the segfault no longer occurs.
+
+      (DER - 2021/04/27, HDFFV-11239)
+
+    - HSYS_GOTO_ERROR now emits the results of GetLastError() on Windows
+
+      HSYS_GOTO_ERROR is an internal macro that is used to produce error
+      messages when system calls fail. These strings include errno and the
+      the associated strerror() value, which are not particularly useful
+      when a Win32 API call fails.
+
+      On Windows, this macro has been updated to include the result of
+      GetLastError(). When a system call fails on Windows, usually only
+      one of errno and GetLastError() will be useful, however we emit both
+      for the user to parse. The Windows error message is not emitted as
+      it would be awkward to free the FormatMessage() buffer given the
+      existing HDF5 error framework. Users will have to look up the error
+      codes in MSDN.
+
+      The format string on Windows has been changed from:
+
+        "%s, errno = %d, error message = '%s'"
+
+      to:
+
+        "%s, errno = %d, error message = '%s', Win32 GetLastError() = %"PRIu32""
+
+      for those inclined to parse it for error values.
+
+      (DER - 2021/03/21)
+
+    - File locking now works on Windows
+
+      Since version 1.10.0, the HDF5 library has used a file locking scheme
+      to help enforce one reader at a time accessing an HDF5 file, which can
+      be helpful when setting up readers and writers to use the single-
+      writer/multiple-readers (SWMR) access pattern.
+
+      In the past, this was only functional on POSIX systems where flock() or
+      fcntl() were present. Windows used a no-op stub that always succeeded.
+
+      HDF5 now uses LockFileEx() and UnlockFileEx() to lock the file using the
+      same scheme as POSIX systems. We lock the entire file when we set up the
+      locks (by passing DWORDMAX as both size parameters to LockFileEx()).
+
+      (DER - 2021/03/19, HDFFV-10191)
+
+    - H5Epush_ret() now requires a trailing semicolon
+
+      H5Epush_ret() is a function-like macro that has been changed to
+      contain a `do {} while(0)` loop. Consequently, a trailing semicolon
+      is now required to end the `while` statement. Previously, a trailing
+      semi would work, but was not mandatory. This change was made to allow
+      clang-format to correctly format the source code.
+
+      (SAM - 2021/03/03)
+
+    - Improved performance of H5Sget_select_elem_pointlist
+
+      Modified library to cache the point after the last block of points
+      retrieved by H5Sget_select_elem_pointlist, so a subsequent call to the
+      same function to retrieve the next block of points from the list can
+      proceed immediately without needing to iterate over the point list.
+
+      (NAF - 2021/01/19)
+
+    - Replaced H5E_ATOM with H5E_ID in H5Epubgen.h
+
+      The term "atom" is archaic and not in line with current HDF5 library
+      terminology, which uses "ID" instead. "Atom" has mostly been purged
+      from the library internals and this change removes H5E_ATOM from
+      the H5Epubgen.h (exposed via H5Epublic.h) and replaces it with
+      H5E_ID.
+
+      (DER - 2020/11/24, HDFFV-11190)
+
+    - Add a new public function H5Ssel_iter_reset
+
+      This function resets a dataspace selection iterator back to an
+      initial state so that it may be used for iteration once more.
+      This can be useful when needing to iterate over a selection
+      multiple times without having to repeatedly create/destroy
+      a selection iterator for that dataspace selection.
+
+      (JTH - 2020/09/18)
+
+    - Remove HDFS VFD stubs
+
+      The original implementation of the HDFS VFD included non-functional
+      versions of the following public API calls when the HDFS VFD is
+      not built as a part of the HDF5 library:
+
+      * H5FD_hdfs_init()
+      * H5Pget_fapl_hdfs()
+      * H5Pset_fapl_hdfs()
+
+      They will remain present in HDF5 1.10 and HDF5 1.12 releases
+      for binary compatibility purposes but have been removed as of 1.14.0.
+
+      Note that this has nothing to do with the real HDFS VFD API calls
+      that are fully functional when the HDFS VFD is configured and built.
+
+      We simply changed:
+
+        #ifdef LIBHDFS
+          <real API call>
+        #else
+          <useless stub>
+        #endif
+
+      to:
+
+        #ifdef LIBHDFS
+          <real API call>
+        #endif
+
+      Which is how the other optional VFDs are handled.
+
+      (DER - 2020/08/27)
+
+    - Add Mirror VFD
+
+      Use TCP/IP sockets to perform write-only (W/O) file I/O on a remote
+      machine. Must be used in conjunction with the Splitter VFD.
+
+      (JOS - 2020/03/13, TBD)
+
+    - Add Splitter VFD
+
+      Maintain separate R/W and W/O channels for "concurrent" file writes
+      to two files using a single HDF5 file handle.
+
+      (JOS - 2020/03/13, TBD)
+
+    - Refactored public exposure of haddr_t type in favor of "object tokens"
+
+      To better accommodate HDF5 VOL connectors where "object addresses in a file"
+      may not make much sense, the following changes were made to the library:
+
+      * Introduced new H5O_token_t "object token" type, which represents a
+        unique and permanent identifier for referencing an HDF5 object within
+        a container; these "object tokens" are meant to replace object addresses.
+        Along with the new type, a new H5Oopen_by_token API call was introduced
+        to open an object by a token, similar to how object addresses were
+        previously used with H5Oopen_by_addr.
+
+      * Introduced new H5Lget_info2, H5Lget_info_by_idx2, H5Literate2, H5Literate_by_name2,
+        H5Lvisit2 and H5Lvisit_by_name2 API calls, along with their associated H5L_info2_t
+        struct and H5L_iterate2_t callback function, which work with the newly-introduced
+        object tokens, instead of object addresses. The original functions have been
+        renamed to version 1 functions and are deprecated in favor of the new version 2
+        functions. The H5L_info_t and H5L_iterate_t types have been renamed to version 1
+        types and are now deprecated in favor of their version 2 counterparts. For each of
+        the functions and types, compatibility macros take place of the original symbols.
+
+      * Introduced new H5Oget_info3, H5Oget_info_by_name3, H5Oget_info_by_idx3,
+        H5Ovisit3 and H5Ovisit_by_name3 API calls, along with their associated H5O_info2_t
+        struct and H5O_iterate2_t callback function, which work with the newly-introduced
+        object tokens, instead of object addresses. The version 2 functions are now
+        deprecated in favor of the version 3 functions. The H5O_info_t and H5O_iterate_t
+        types have been renamed to version 1 types and are now deprecated in favor of their
+        version 2 counterparts. For each, compatibility macros take place of the original
+        symbols.
+
+      * Introduced new H5Oget_native_info, H5Oget_native_info_by_name and
+        H5Oget_native_info_by_idx API calls, along with their associated H5O_native_info_t
+        struct, which are used to retrieve the native HDF5 file format-specific information
+        about an object. This information (such as object header info and B-tree/heap info)
+        has been removed from the new H5O_info2_t struct so that the more generic
+        H5Oget_info(_by_name/_by_idx)3 routines will not try to retrieve it for non-native
+        VOL connectors.
+
+      * Added new H5Otoken_cmp, H5Otoken_to_str and H5Otoken_from_str routines to compare
+        two object tokens, convert an object token into a nicely-readable string format and
+        to convert an object token string back into a real object token, respectively.
+
+      (DER, QAK, JTH - 2020/01/16)
+
+    - Add new public function H5Sselect_adjust.
+
+      This function shifts a dataspace selection by a specified logical offset
+      within the dataspace extent.  This can be useful for VOL developers to
+      implement chunked datasets.
+
+      (NAF - 2019/11/18)
+
+    - Add new public function H5Sselect_project_intersection.
+
+      This function computes the intersection between two dataspace selections
+      and projects that intersection into a third selection.  This can be useful
+      for VOL developers to implement chunked or virtual datasets.
+
+      (NAF - 2019/11/13, ID-148)
+
+    - Add new public function H5VLget_file_type.
+
+      This function returns a datatype equivalent to the supplied datatype but
+      with the location set to be in the file.  This datatype can then be used
+      with H5Tconvert to convert data between file and in-memory representation.
+      This function is intended for use only by VOL connector developers.
+
+      (NAF - 2019/11/08, ID-127)
+
+
+    Parallel Library:
+    -----------------
+    -
+
+
+    Fortran Library:
+    ----------------
+    - H5Fget_name_f fixed to handle correctly trailing whitespaces and
+      newly allocated buffers.
+
+      (MSB - 2021/08/30, github-826,972)
+
+    - Add wrappers for H5Pset/get_file_locking() API calls
+
+        h5pget_file_locking_f()
+        h5pset_file_locking_f()
+
+      See the configure option discussion for HDFFV-11092 (above) for more
+      information on the file locking feature and how it's controlled.
+
+      (DER - 2020/07/30, HDFFV-11092)
+
+    C++ Library:
+    ------------
+    - Add wrappers for H5Pset/get_file_locking() API calls
+
+        FileAccPropList::setFileLocking()
+        FileAccPropList::getFileLocking()
+
+      See the configure option discussion for HDFFV-11092 (above) for more
+      information on the file locking feature and how it's controlled.
+
+      (DER - 2020/07/30, HDFFV-11092)
+
+
+    Java Library:
+    -------------
+    - Replaced HDF5AtomException with HDF5IdException
+
+      Since H5E_ATOM changed to H5E_ID in the C library, the Java exception
+      that wraps the error category was also renamed. Its functionality
+      remains unchanged aside from the name.
+
+      (See also the HDFFV-11190 note in the C library section)
+
+      (DER - 2020/11/24, HDFFV-11190)
+
+    - Added new H5S functions.
+
+      H5Sselect_copy, H5Sselect_shape_same, H5Sselect_adjust,
+      H5Sselect_intersect_block, H5Sselect_project_intersection,
+      H5Scombine_hyperslab, H5Smodify_select, H5Scombine_select
+      wrapper functions added.
+
+      (ADB - 2020/10/27, HDFFV-10868)
+
+    - Add wrappers for H5Pset/get_file_locking() API calls
+
+        H5Pset_file_locking()
+        H5Pget_use_file_locking()
+        H5Pget_ignore_disabled_file_locking()
+
+      Unlike the C++ and Fortran wrappers, there are separate getters for the
+      two file locking settings, each of which returns a boolean value.
+
+      See the configure option discussion for HDFFV-11092 (above) for more
+      information on the file locking feature and how it's controlled.
+
+      (DER - 2020/07/30, HDFFV-11092)
+
+    - Added ability to test java library with VOLs.
+
+      Created a new CMake script that combines the java and vol test scripts.
+
+      (ADB - 2020/02/03, HDFFV-10996)
+
+    - Tests fail for non-English locales.
+
+      In the JUnit tests with a non-English locale, only the part before
+      the decimal comma is replaced by XXXX and this leads to a comparison
+      error. Changed the regex for the Time substitution.
+
+      (ADB - 2020/01/09, HDFFV-10995)
+
+
+    Tools:
+    ------
+    - Added a new (unix ONLY) parallel meta tool 'h5dwalk', which utilizes the
+      mpifileutils (https://hpc.github.io/mpifileutils) open source utility
+      library to enable parallel execution of other HDF5 tools.
+      This approach can greatly enhance the serial hdf5 tool performance over large
+      collections of files by utilizing MPI parallelism to distribute an application
+      load over many independent MPI ranks and files.
+
+      An introduction to the mpifileutils library and initial 'User Guide' for
+      the new 'h5dwalk" tool can be found at:
+      https://github.com/HDFGroup/hdf5doc/tree/master/RFCs/HDF5/tools/parallel_tools
+
+      (RAW - 2021/10/25)
+
+    - Refactored the perform tools and removed depends on test library.
+
+      Moved the perf and h5perf tools from tools/test/perform to
+      tools/src/h5perf so that they can be installed. This required
+      that the test library dependency be removed by copying the
+      needed functions from h5test.c.
+      The standalone scripts and other perform tools remain in the
+      tools/test/perform folder.
+
+      (ADB - 2021/08/10)
+
+    - Removed partial long exceptions
+
+      Some of the tools accepted shortened versions of the long options
+      (ex: --datas instead of --dataset). These were implemented inconsistently,
+      are difficult to maintian, and occasionally block useful long option
+      names. These partial long options have been removed from all the tools.
+
+      (DER - 2021/08/03)
+
+    - h5repack added help text for user-defined filters.
+
+      Added help text line that states the valid values of the filter flag
+      for user-defined filters;
+          filter_flag: 1 is OPTIONAL or 0 is MANDATORY
+
+      (ADB - 2021/01/14, HDFFV-11099)
+
+    - Added h5delete tool
+
+      Deleting HDF5 storage when using the VOL can be tricky when the VOL
+      does not create files. The h5delete tool is a simple wrapper around
+      the H5Fdelete() API call that uses the VOL specified in the
+      HDF5_VOL_CONNECTOR environment variable to delete a "file". If
+      the call to H5Fdelete() fails, the tool will attempt to use
+      the POSIX remove(3) call to remove the file.
+
+      Note that the HDF5 library does currently have support for
+      H5Fdelete() in the native VOL connector.
+
+      (DER - 2020/12/16)
+
+    - h5repack added options to control how external links are handled.
+
+      Currently h5repack preserves external links and cannot copy and merge
+      data from the external files. Two options, merge and prune, were added to
+      control how to merge data from an external link into the resulting file.
+          --merge             Follow external soft link recursively and merge data.
+          --prune             Do not follow external soft links and remove link.
+          --merge --prune     Follow external link, merge data and remove dangling link.
+
+      (ADB - 2020/08/05, HDFFV-9984)
+
+    - h5repack was fixed to repack the reference attributes properly.
+      The code line that checks if the update of reference inside a compound
+      datatype is misplaced outside the code block loop that carries out the
+      check. In consequence, the next attribute that is not the reference
+      type was repacked again as the reference type and caused the failure of
+      repacking. The fix is to move the corresponding code line to the correct
+      code block.
+
+       (KY -2020/02/07, HDFFV-11014)
+
+    - h5diff was updated to use the new reference APIs.
+
+       h5diff uses the new reference APIs to compare references.
+       Attribute references can also be compared.
+
+      (ADB - 2019/12/19, HDFFV-10980)
+
+    - h5dump and h5ls were updated to use the new reference APIs.
+
+      The tools library now use the new reference APIs to inspect a
+      file. Also the DDL spec was updated to reflect the format
+      changes produced with the new APIs. The export API and support
+      functions in the JNI were updated to match.
+
+      (ADB - 2019/12/06, HDFFV-10876 and HDFFV-10877)
+
+
+    High-Level APIs:
+    ----------------
+    - added set/get for unsigned long long attributes
+
+      The attribute writing high-level API has been expanded to include
+      public set/get functions for ULL attributes, analogously to the
+      existing set/get for other types.
+
+      (AF - 2021/09/08)
+
+    C Packet Table API:
+    -------------------
+    -
+
+    Internal header file:
+    ---------------------
+    -
+
+    Documentation:
+    --------------
+    -
+
+
+New platforms, languages and compilers tested
+=============================================
+    - Linux 5.13.14-200.fc34 #1 SMP x86_64  GNU/Linux Fedora34
+    - Linux 5.11.0-34-generic #36-Ubuntu SMP x86_64 GNU/Linux Ubuntu 20.04
+    - Linux 5.3.18-22-default #1 SMP x86_64  GNU/Linux SUSE15sp2
+    - Linux-4.14.0-115.21.2 #1 SMP ppc64le GNU/Linux
+    - Linux-4.12.14-150.75-default #1 SMP x86_64 GNU/Linux
+    - macOS Apple M1 11.6 Darwin 20.6.0 arm64
+    - macOS Big Sur 11.3.1 Darwin 20.4.0 x86_64
+    - clang versions 11.0.1, 12.0.5
+    - Visual Studio 2019 w/ clang 12.0.0 with MSVC-like command-line
+
+
+Bug Fixes since HDF5-1.12.0 release
+===================================
+    Library
+    -------
+    - Fixed an H5Pget_filter_by_id1/2() assert w/ out of range filter IDs
+
+      Both H5Pget_filter_by_id1 and 2 did not range check the filter ID, which
+      could trip as assert in debug versions of the library. The library now
+      returns a normal HDF5 error when the filter ID is out of range.
+
+      (DER - 2021/11/23, HDFFV-11286)
+
+    - 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)
+
+    - Fixed cross platform incompatibility of references within variable length
+      types
+
+      Reference types within variable length types previously could not be
+      read on a platform with different endianness from where they were
+      written. Fixed so cross platform portability is restored.
+
+      (NAF - 2021/09/30)
+
+    - Detection of simple data transform function "x"
+
+      In the case of the simple data transform function "x" the (parallel)
+      library recognizes this is the same as not applying this data transform
+      function. This improves the I/O performance. In the case of the parallel
+      library, it also avoids breaking to independent I/O, which makes it
+      possible to apply a filter when writing or reading data to or from
+      the HDF5 file.
+
+      (JWSB - 2021/09/13)
+
+    - Fixed an invalid read and memory leak when parsing corrupt file space
+      info messages
+
+      When the corrupt file from CVE-2020-10810 was parsed by the library,
+      the code that imports the version 0 file space info object header
+      message to the version 1 struct could read past the buffer read from
+      the disk, causing an invalid memory read. Not catching this error would
+      cause downstream errors that eventually resulted in a previously
+      allocated buffer to be unfreed when the library shut down. In builds
+      where the free lists are in use, this could result in an infinite loop
+      and SIGABRT when the library shuts down.
+
+      We now track the buffer size and raise an error on attempts to read
+      past the end of it.
+
+      (DER - 2021/08/12, HDFFV-11053)
+
+
+    - Fixed CVE-2018-14460
+
+      The tool h5repack produced a segfault when the rank in dataspace
+      message was corrupted, causing invalid read while decoding the
+      dimension sizes.
+
+      The problem was fixed by ensuring that decoding the dimension sizes
+      and max values will not go beyond the end of the buffer.
+
+      (BMR - 2021/05/12, HDFFV-11223)
+
+    - Fixed CVE-2018-11206
+
+      The tool h5dump produced a segfault when the size of a fill value
+      message was corrupted and caused a buffer overflow.
+
+      The problem was fixed by verifying the fill value's size
+      against the buffer size before attempting to access the buffer.
+
+      (BMR - 2021/03/15, HDFFV-10480)
+
+    - Fixed CVE-2018-14033 (same issue as CVE-2020-10811)
+
+      The tool h5dump produced a segfault when the storage size message
+      was corrupted and caused a buffer overflow.
+
+      The problem was fixed by verifying the storage size against the
+      buffer size before attempting to access the buffer.
+
+      (BMR - 2021/03/15, HDFFV-11159/HDFFV-11049)
+
+    - Remove underscores on header file guards
+
+      Header file guards used a variety of underscores at the beginning of the define.
+
+      Removed all leading (some trailing) underscores from header file guards.
+
+      (ADB - 2021/03/03, #361)
+
+    - Fixed a segmentation fault
+
+      A segmentation fault occurred with a Mathworks corrupted file.
+
+      A detection of accessing a null pointer was added to prevent the problem.
+
+      (BMR - 2021/02/19, HDFFV-11150)
+
+    - Fixed issue with MPI communicator and info object not being
+      copied into new FAPL retrieved from H5F_get_access_plist
+
+      Added logic to copy the MPI communicator and info object into
+      the output FAPL. MPI communicator is retrieved from the VFD, while
+      the MPI info object is retrieved from the file's original FAPL.
+
+      (JTH - 2021/02/15, HDFFV-11109)
+
+    - Fixed problems with vlens and refs inside compound using
+      H5VLget_file_type()
+
+      Modified library to properly ref count H5VL_object_t structs and only
+      consider file vlen and reference types to be equal if their files are
+      the same.
+
+      (NAF - 2021/01/22)
+
+    - Fixed CVE-2018-17432
+
+      The tool h5repack produced a segfault on a corrupted file which had
+      invalid rank for scalar or NULL datatype.
+
+      The problem was fixed by modifying the dataspace encode and decode
+      functions to detect and report invalid rank. h5repack now fails
+      with an error message for the corrupted file.
+
+      (BMR - 2020/10/26, HDFFV-10590)
+
+    - Creation of dataset with optional filter
+
+      When the combination of type, space, etc doesn't work for filter
+      and the filter is optional, it was supposed to be skipped but it was
+      not skipped and the creation failed.
+
+      Allowed the creation of the dataset in such a situation.
+
+      (BMR - 2020/08/13, HDFFV-10933)
+
+    - Explicitly declared dlopen to use RTLD_LOCAL
+
+      dlopen documentation states that if neither RTLD_GLOBAL nor
+      RTLD_LOCAL are specified, then the default behavior is unspecified.
+      The default on linux is usually RTLD_LOCAL while macos will default
+      to RTLD_GLOBAL.
+
+      (ADB - 2020/08/12, HDFFV-11127)
+
+    - H5Sset_extent_none() sets the dataspace class to H5S_NO_CLASS which
+      causes asserts/errors when passed to other dataspace API calls.
+
+      H5S_NO_CLASS is an internal class value that should not have been
+      exposed via a public API call.
+
+      In debug builds of the library, this can cause assert() function to
+      trip. In non-debug builds, it will produce normal library errors.
+
+      The new library behavior is for H5Sset_extent_none() to convert
+      the dataspace into one of type H5S_NULL, which is better handled
+      by the library and easier for developers to reason about.
+
+      (DER - 2020/07/27, HDFFV-11027)
+
+    - Fixed issues CVE-2018-13870 and CVE-2018-13869
+
+      When a buffer overflow occurred because a name length was corrupted
+      and became very large, h5dump crashed on memory access violation.
+
+      A check for reading pass the end of the buffer was added to multiple
+      locations to prevent the crashes and h5dump now simply fails with an
+      error message when this error condition occurs.
+
+      (BMR - 2020/07/22, HDFFV-11120 and HDFFV-11121)
+
+    - Fixed the segmentation fault when reading attributes with multiple threads
+
+      It was reported that the reading of attributes with variable length string
+      datatype will crash with segmentation fault particularly when the number of
+      threads is high (>16 threads).  The problem was due to the file pointer that
+      was set in the variable length string datatype for the attribute.  That file
+      pointer was already closed when the attribute was accessed.
+
+      The problem was fixed by setting the file pointer to the current opened file pointer
+      when the attribute was accessed.  Similar patch up was done before when reading
+      dataset with variable length string datatype.
+
+      (VC - 2020/07/13, HDFFV-11080)
+
+    - Fixed CVE-2020-10810
+
+      The tool h5clear produced a segfault during an error recovery in
+      the superblock decoding.  An internal pointer was reset to prevent
+      further accessing when it is not assigned with a value.
+
+      (BMR - 2020/06/29, HDFFV-11053)
+
+    - Fixed CVE-2018-17435
+
+      The tool h52gif produced a segfault when the size of an attribute
+      message was corrupted and caused a buffer overflow.
+
+      The problem was fixed by verifying the attribute message's size
+      against the buffer size before accessing the buffer.  h52gif was
+      also fixed to display the failure instead of silently exiting
+      after the segfault was eliminated.
+
+      (BMR - 2020/06/19, HDFFV-10591)
+
+
+    Java Library
+    ------------
+    - JNI utility function does not handle new references.
+
+      The JNI utility function for converting reference data to string did
+      not use the new APIs. In addition to fixing that function, added new
+      java tests for using the new APIs.
+
+      (ADB - 2021/02/16, HDFFV-11212)
+
+    - The H5FArray.java class, in which virtually the entire execution time
+      is spent using the HDFNativeData method that converts from an array
+      of bytes to an array of the destination Java type.
+
+        1. Convert the entire byte array into a 1-d array of the desired type,
+           rather than performing 1 conversion per row;
+        2. Use the Java Arrays method copyOfRange to grab the section of the
+           array from (1) that is desired to be inserted into the destination array.
+
+      (PGT,ADB - 2020/12/13, HDFFV-10865)
+
+    - Added ability to test java library with VOLs.
+
+      Created a new CMake script that combines the java and vol test scripts.
+
+      (ADB - 2020/02/03, HDFFV-10996)
+
+    - Tests fail for non-English locales.
+
+      In the JUnit tests with a non-English locale, only the part before
+      the decimal comma is replaced by XXXX and this leads to a comparison
+      error. Changed the regex for the Time substitution.
+
+      (ADB - 2020/01/09, HDFFV-10995)
+
+
+    Configuration
+    -------------
+    - 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 the trailing "hdf5" directory was not removed.
+      This "hdf5" additional directory has been removed.
+
+      (ADB - 2021/09/27)
+
+    - Corrected pkg-config compile script
+
+      It was discovered that the position of the "$@" argument for the command
+      in the compile script may fail on some platforms and configurations. The
+      position of the "$@"command argument was moved before the pkg-config sub command.
+
+      (ADB - 2021/08/30)
+
+    - Fixed CMake C++ compiler flags
+
+      A recent refactoring of the C++ configure files accidentally removed the
+      file that executed the enable_language command for C++ needed by the
+      HDFCXXCompilerFlags.cmake file. Also updated the intel warnings files,
+      including adding support for windows platforms.
+
+      (ADB - 2021/08/10)
+
+    - Better support for libaec (open-source Szip library) in CMake
+
+      Implemented better support for libaec 1.0.5 (or later) library. This version
+      of libaec contains improvements for better integration with HDF5. Furthermore,
+      the variable USE_LIBAEC_STATIC has been introduced to allow to make use of
+      static version of libaec library. Use libaec_DIR or libaec_ROOT to set
+      the location in which libaec can be found.
+
+      Be aware, the Szip library of libaec 1.0.4 depends on another library within
+      libaec library. This dependency is not specified in the current CMake
+      configuration which means that one can not use the static Szip library of
+      libaec 1.0.4 when building HDF5. This has been resolved in libaec 1.0.5.
+
+      (JWSB - 2021/06/22)
+
+    - Refactor CMake configure for Fortran
+
+      The Fortran configure tests for KINDs reused a single output file that was
+      read to form the Integer and Real Kinds defines. However, if config was run
+      more then once, the CMake completed variable prevented the tests from executing
+      again and the last value saved in the file was used to create the define.
+      Creating separate files for each KIND solved the issue.
+
+      In addition the test for H5_PAC_C_MAX_REAL_PRECISION was not pulling in
+      defines for proper operation and did not define H5_PAC_C_MAX_REAL_PRECISION
+      correctly for a zero value. This was fixed by supplying the required defines.
+      In addition it was moved from the Fortran specific HDF5UseFortran.camke file
+      to the C centric ConfigureChecks.cmake file.
+
+      (ADB - 2021/06/03)
+
+    - Move emscripten flag to compile flags
+
+      The emscripten flag, -O0, was removed from target_link_libraries command
+      to the correct target_compile_options command.
+
+      (ADB - 2021/04/26 HDFFV-11083)
+
+    - Remove arbitrary warning flag groups from CMake builds
+
+      The arbitrary groups were created to reduce the quantity of warnings being
+      reported that overwhelmed testing report systems. Considerable work has
+      been accomplished to reduce the warning count and these arbitrary groups
+      are no longer needed.
+      Also the default for all warnings, HDF5_ENABLE_ALL_WARNINGS, is now ON.
+
+      Visual Studio warnings C4100, C4706, and C4127 have been moved to
+      developer warnings, HDF5_ENABLE_DEV_WARNINGS, and are disabled for normal builds.
+
+      (ADB - 2021/03/22, HDFFV-11228)
+
+    - Reclassify CMake messages, to allow new modes and --log-level option
+
+      CMake message commands have a mode argument. By default, STATUS mode
+      was chosen for any non-error message. CMake version 3.15 added additional
+      modes, NOTICE, VERBOSE, DEBUG and TRACE. All message commands with a mode
+      of STATUS were reviewed and most were reclassified as VERBOSE. The new
+      mode was protected by a check for a CMake version of at least 3.15. If CMake
+      version 3.17 or above is used, the user can use the command line option
+      of "--log-level" to further restrict which message commands are displayed.
+
+      (ADB - 2021/01/11, HDFFV-11144)
+
+    - Fixes Autotools determination of the stat struct having an st_blocks field
+
+      A missing parenthesis in an autoconf macro prevented building the test
+      code used to determine if the stat struct contains the st_blocks field.
+      Now that the test functions correctly, the H5_HAVE_STAT_ST_BLOCKS #define
+      found in H5pubconf.h will be defined correctly on both the Autotools and
+      CMake. This #define is only used in the tests and does not affect the
+      HDF5 C library.
+
+      (DER - 2021/01/07, HDFFV-11201)
+
+    - Add missing ENV variable line to hdfoptions.cmake file
+
+      Using the build options to use system SZIP/ZLIB libraries need to also
+      specify the library root directory. Setting the {library}_ROOT ENV
+      variable was added to the hdfoptions.cmake file.
+
+      (ADB - 2020/10/19 HDFFV-11108)
+
+
+    Tools
+    -----
+    - Changed how h5dump and h5ls identify long double.
+
+      Long double support is not consistent across platforms. Tools will always
+      identify long double as 128-bit [little/big]-endian float nn-bit precision.
+      New test file created for datasets with attributes for float, double and
+      long double. In addition any unknown integer or float datatype will now
+      also show the number of bits for precision.
+      These files are also used in the java tests.
+
+      (ADB - 2021/03/24, HDFFV-11229,HDFFV-11113)
+
+    - Fixed tools argument parsing.
+
+      Tools parsing used the length of the option from the long array to match
+      the option from the command line. This incorrectly matched a shorter long
+      name option that happened to be a subset of another long option.
+      Changed to match whole names.
+
+      (ADB - 2021/01/19, HDFFV-11106)
+
+    - The tools library was updated by standardizing the error stack process.
+
+      General sequence is:
+        h5tools_setprogname(PROGRAMNAME);
+        h5tools_setstatus(EXIT_SUCCESS);
+        h5tools_init();
+        ... process the command-line (check for error-stack enable) ...
+        h5tools_error_report();
+        ... (do work) ...
+        h5diff_exit(ret);
+
+      (ADB - 2020/07/20, HDFFV-11066)
+
+    - h5diff fixed a command line parsing error.
+
+      h5diff would ignore the argument to -d (delta) if it is smaller than DBL_EPSILON.
+      The macro H5_DBL_ABS_EQUAL was removed and a direct value comparison was used.
+
+      (ADB - 2020/07/20, HDFFV-10897)
+
+    - h5diff added a command line option to ignore attributes.
+
+      h5diff would ignore all objects with a supplied path if the exclude-path argument is used.
+      Adding the exclude-attribute argument will only exclude attributes, with the supplied path,
+      from comparison.
+
+      (ADB - 2020/07/20, HDFFV-5935)
+
+    - h5diff added another level to the verbose argument to print filenames.
+
+      Added verbose level 3 that is level 2 plus the filenames. The levels are:
+        0 : Identical to '-v' or '--verbose'
+        1 : All level 0 information plus one-line attribute status summary
+        2 : All level 1 information plus extended attribute status report
+        3 : All level 2 information plus file names
+
+      (ADB - 2020/07/20, HDFFV-1005)
+
+    - h5repack was fixed to repack the reference attributes properly.
+
+      The code line that checks if the update of reference inside a compound
+      datatype is misplaced outside the code block loop that carries out the
+      check. In consequence, the next attribute that is not the reference
+      type was repacked again as the reference type and caused the failure of
+      repacking. The fix is to move the corresponding code line to the correct
+      code block.
+
+      (KY -2020/02/10, HDFFV-11014)
+
+    - h5diff was updated to use the new reference APIs.
+
+      h5diff uses the new reference APIs to compare references.
+      Attribute references can also be compared.
+
+      (ADB - 2019/12/19, HDFFV-10980)
+
+    - h5dump and h5ls were updated to use the new reference APIs.
+
+      The tools library now use the new reference APIs to inspect a
+      file. Also the DDL spec was updated to reflect the format
+      changes produced with the new APIs. The export API and support
+      functions in the JNI were updated to match.
+
+      (ADB - 2019/12/06, HDFFV-10876 and HDFFV-10877)
+
+
+    Performance
+    -------------
+    -
+
+
+    Fortran API
+    -----------
+    - Corrected INTERFACE INTENT(IN) to INTENT(OUT) for buf_size in h5fget_file_image_f.
+
+      (MSB - 2020/02/18, HDFFV-11029)
+
+
+    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
+    --------
+    - Added DataSet::operator=
+
+      Some compilers complain if the copy constructor is given explicitly
+      but the assignment operator is implicitly set to default.
+
+      (2021/05/19)
+
+
+    Testing
+    -------
+    - Stopped java/test/junit.sh.in installing libs for testing under ${prefix}
+
+      Lib files needed are now copied to a subdirectory in the java/test
+      directory, and on Macs the loader path for libhdf5.xxxs.so is changed
+      in the temporary copy of libhdf5_java.dylib.
+
+      (LRK, 2020/07/02, HDFFV-11063)
+
+
+Platforms Tested
+===================
+
+    Linux 5.13.14-200.fc34           GNU gcc (GCC) 11.2.1 2021078 (Red Hat 11.2.1-1)
+    #1 SMP x86_64  GNU/Linux         GNU Fortran (GCC) 11.2.1 2021078 (Red Hat 11.2.1-1)
+    Fedora34                         clang version 12.0.1 (Fedora 12.0.1-1.fc34)
+                                     (cmake and autotools)
+
+    Linux 5.11.0-34-generic          GNU gcc (GCC) 9.3.0-17ubuntu1
+    #36-Ubuntu SMP x86_64 GNU/Linux  GNU Fortran (GCC) 9.3.0-17ubuntu1
+    Ubuntu 20.04                     Ubuntu clang version 10.0.0-4
+                                     (cmake and autotools)
+
+    Linux 5.8.0-63-generic           GNU gcc (GCC) 10.3.0-1ubuntu1
+    #71-Ubuntu SMP x86_64 GNU/Linux  GNU Fortran (GCC) 10.3.0-1ubuntu1
+    Ubuntu20.10                      Ubuntu clang version 11.0.0-2
+                                     (cmake and autotools)
+
+    Linux 5.3.18-22-default          GNU gcc (SUSE Linux) 7.5.0
+    #1 SMP x86_64  GNU/Linux         GNU Fortran (SUSE Linux) 7.5.0
+    SUSE15sp2                        clang version 7.0.1 (tags/RELEASE_701/final 349238)
+                                     (cmake and autotools)
+
+    Linux-4.14.0-115.21.2            spectrum-mpi/rolling-release
+    #1 SMP ppc64le GNU/Linux             clang 8.0.1, 11.0.1
+    (lassen)                             GCC 7.3.1
+                                         XL 16.1.1.2
+                                     (cmake)
+
+    Linux-4.12.14-150.75-default     cray-mpich/7.7.10
+    #1 SMP x86_64 GNU/Linux              GCC 7.3.0, 8.2.0
+    (cori)                               Intel (R) Version 19.0.3.199
+                                     (cmake)
+
+    Linux-4.12.14-197.86-default     cray-mpich/7.7.6
+    # 1SMP x86_64 GNU/Linux              GCC  7.3.0, 9.3.0, 10.2.0
+    (mutrino)                            Intel (R) Version 17.0.4, 18.0.5, 19.1.3
+                                     (cmake)
+
+    Linux 3.10.0-1160.36.2.el7.ppc64 gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39)
+    #1 SMP ppc64be GNU/Linux         g++ (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39)
+    Power8 (echidna)                 GNU Fortran (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39)
+
+    Linux 3.10.0-1160.24.1.el7       GNU C (gcc), Fortran (gfortran), C++ (g++)
+    #1 SMP x86_64 GNU/Linux          compilers:
+    Centos7                              Version 4.8.5 20150623 (Red Hat 4.8.5-4)
+    (jelly/kituo/moohan)                 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
+                                     GNU C (gcc) and C++ (g++) 4.8.5 compilers
+                                         with NAG Fortran Compiler Release 6.1(Tozai)
+                                     Intel(R) C (icc) and C++ (icpc) 17.0.0.098 compilers
+                                         with NAG Fortran Compiler Release 6.1(Tozai)
+                                     MPICH 3.1.4 compiled with GCC 4.9.3
+                                     MPICH 3.3 compiled with GCC 7.2.0
+                                     OpenMPI 2.1.6 compiled with icc 18.0.1
+                                     OpenMPI 3.1.3 and 4.0.0 compiled with GCC 7.2.0
+                                     PGI C, Fortran, C++ for 64-bit target on
+                                     x86_64;
+                                         Version 19.10-0
+
+    Linux-3.10.0-1127.0.0.1chaos     openmpi-4.0.0
+    #1 SMP x86_64 GNU/Linux              clang 6.0.0, 11.0.1
+    (quartz)                             GCC 7.3.0, 8.1.0
+                                         Intel 16.0.4, 18.0.2, 19.0.4
+
+    macOS Apple M1 11.6              Apple clang version 12.0.5 (clang-1205.0.22.11)
+    Darwin 20.6.0 arm64              gfortran GNU Fortran (Homebrew GCC 11.2.0) 11.1.0
+    (macmini-m1)                     Intel icc/icpc/ifort version 2021.3.0 202106092021.3.0 20210609
+
+    macOS Big Sur 11.3.1             Apple clang version 12.0.5 (clang-1205.0.22.9)
+    Darwin 20.4.0 x86_64             gfortran GNU Fortran (Homebrew GCC 10.2.0_3) 10.2.0
+    (bigsur-1)                       Intel icc/icpc/ifort version 2021.2.0 20210228
+
+    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
+
+    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
+
+    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
+
+
+    Linux 2.6.32-573.22.1.el6        GNU C (gcc), Fortran (gfortran), C++ (g++)
+    #1 SMP x86_64 GNU/Linux          compilers:
+    Centos6                              Version 4.4.7 20120313
+    (platypus)                           Version 4.9.3, 5.3.0, 6.2.0
+                                     MPICH 3.1.4 compiled with GCC 4.9.3
+                                     PGI C, Fortran, C++ for 64-bit target on
+                                     x86_64;
+                                         Version 19.10-0
+
+    Windows 10 x64                  Visual Studio 2015 w/ Intel C/C++/Fortran 18 (cmake)
+                                    Visual Studio 2017 w/ Intel C/C++/Fortran 19 (cmake)
+                                    Visual Studio 2019 w/ clang 12.0.0
+                                        with MSVC-like command-line (C/C++ only - cmake)
+                                    Visual Studio 2019 w/ Intel Fortran 19 (cmake)
+                                    Visual Studio 2019 w/ MSMPI 10.1 (C only - cmake)
+
+
+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.
+
+    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.
+
+The issues with the gif tool are:
+    HDFFV-10592 CVE-2018-17433
+    HDFFV-10593 CVE-2018-17436
+    HDFFV-11048 CVE-2020-10809
+These CVE issues have not yet been addressed and can be avoided by not building
+the gif tool. Disable building the High-Level tools with these options:
+    autotools:   --disable-hltools
+    cmake:       HDF5_BUILD_HL_TOOLS=OFF