NEWS

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hdf5lib 2.2.0.1

• Fixed silent data corruption: ZFP with NaN/NA/Inf or non-native byte order, Blosc2's ZFP codecs and truncate-precision pre-filter on non-float data, and Blosc2 with array datatypes or after Fletcher32/scale-offset.
• Fixed silent data corruption in Blosc2 with both delta and truncate-precision: every block of a chunk after the first came back wrong. Chunks already written that way cannot be read back correctly.
• Fixed silent data corruption in lossy ZFP on integers. It now declines unsigned types (values near 0 came back near the type's maximum), and refuses chunks holding values of magnitude 2^30 or more (2^62 for 64-bit), which overflowed. Reversible ZFP still takes any integer.
• Blosc2 cd_values now follow the reference HDF5-Blosc2 layout, so h5py/hdf5plugin can read and append to hdf5lib's Blosc2 datasets (including 1-D chunks). The old layout is still accepted.
• Snappy (32003) now writes snappy-cuda's chunk format and reads both; hdf5lib 2.2.0.0 and earlier can't read the new chunks.
• The BitRound read shim moved off SZ3's filter ID (32024) to its own (32032). Read shims no longer override real plugins.
• Blosc and Blosc2 now reuse worker threads across chunks, and join them when HDF5 shuts down.
• New C API: hdf5lib_set_blosc2(), hdf5lib_set_blosc_nthreads(), hdf5lib_get_blosc_nthreads(), Blosc2 codec/pre-filter constants, and declarations for the H5Pset_zfp_*() helpers.
• hdf5lib.h now defines HDF5LIB_VERSION (2020001 for 2.2.0.1), its parts, and HDF5LIB_VERSION_STRING, so packages can test the hdf5lib version with #if.
• All filters fail cleanly on truncated or corrupt chunks.
• Datasets copied from another's creation property list (e.g. by h5repack) keep their ZFP, Blosc2, and Bitshuffle settings.
• Invalid settings or unsupported chunks now fail at H5Dcreate2(), or are stored unfiltered by optional filters, instead of failing every chunk.
• Fixed oversized-chunk overflows in Snappy and LZF, a ZFP datatype leak, and UBSan issues in the bundled ZFP.
• Fixed a UBSan error in the bundled c-blosc, which called its bitshuffle routine through a mismatched function pointer on every bitshuffled Blosc chunk.
• Compiled code no longer references stderr (R CMD check).
• Documentation corrections and expanded h5py/hdf5plugin interoperability tests.

hdf5lib 2.2.0.0 (2026-09-09)

• Enables installation to read-only directories.
• Dependency updates: HDF5 (2.1.1 to 2.2.0), c-blosc2 (2.23.1 to 3.3.3), and libaec (1.1.6 to 1.1.7).

hdf5lib 2.1.1.2 (2026-07-21)

• Patch c-blosc2-2.23.1/blosc/frame.c for strncpy warnings on GCC 16.

hdf5lib 2.1.1.1 (2026-05-15)

• Respect LD and STRIP env vars during linking step (allows cross-platform builds).
• Patched strncpy warnings introduced by GCC 16 in src/H5FDsplitter.c.

hdf5lib 2.1.1.0 (2026-04-02)

• Updated HDF5 to 2.1.1.
• Migrated from zlib to zlib-ng for gzip/deflate compression.
• Added Szip (libaec), Bzip2, LZF, LZ4, Zstandard (Zstd), Snappy, Bitshuffle, ZFP, Blosc, and Blosc2.

hdf5lib 2.0.0.6 (2026-02-19)

• Accept decimal values for api argument in c_flags() and ld_flags().
• New hdf5lib hex logo.
• Updated documentation.

hdf5lib 2.0.0.5 (2026-01-14)

• Patched misaligned address in HDF5's H5Tconv_enum.c file.

hdf5lib 2.0.0.4 (2025-12-22)

• Patched zlib win32/Makefile.gcc for conda-forge compatibility.

hdf5lib 2.0.0.3 (2025-12-14)

• Patched misaligned address in HDF5's H5Tvlen.c file.
• Fix for Alpine Linux (musl) CRAN check.
• Clarified that c_flags() and ld_flags's api argument should be numeric.

hdf5lib 2.0.0.2 (2025-12-02)

• Updated to HDF5 2.0.0
• Added api argument to c_flags to control exposed HDF5 API.
• Customized HDF5 build configuration for R environment.

hdf5lib 1.14.6.9

• Added additional CPPFLAGS include directories needed by Fedora builders.
• Automated build testing using rhub github actions.

hdf5lib 1.14.6.8 (2025-11-19)

• Fixed compiler flags for Fedora builders.
• Renamed libhdf5.a to libhdf5z.a eliminate ambiguity with system libraries.
• Paths returned by c_flags() and ld_flags() are only quoted when necessary.

hdf5lib 1.14.6.7 (2025-11-17)

• Corrected link to inst/COPYRIGHTS.

hdf5lib 1.14.6.6

• Added HDF5 and zlib copyright holders to DESCRIPTION.

hdf5lib 1.14.6.5

• Fixed compilation error identified on CRAN's Fedora builders.

hdf5lib 1.14.6.4 (2025-11-10)

• Initial CRAN submission.