v4.10.0

[WardF]

4.10.0 - February 25, 2026

• Regularize, cleanup, and refactor various AWS features, especially WRT regularizing AWS-related constants. See Github 3229 for more information.
• Add extra failure handling to the daos inferencing. See Github 3238 for more information.
• Regularize, cleanup, and refactor various AWS features, especially WRT regularizing AWS-related constants. See Github 3229 for more information.
• Add compatibility with HDF5 2.0.0. See Github #3247 for more information.
• Introduce consolidated metadata Github #3225 via mode=consolidated or NCZARR_CONSOLIDATED
• Fix the H5FD_class_t problems. See Github 3202 for more information.
• Begin the consolidation of global state into two files: libdispatch/dglobal.c and include/ncglobal.h. See Github 3197 for more information.
• Modify the way xarray attribute sets are handled. See Github 3218 for more information.
• Fix Issue with Numcodecs encoding problems where integer filter parameters are being encoded as strings. See Github 3201 for more information.
• Clean up minor problems with DAP2/DAP4 code. See Github #3215 for more information.
• Cleanup RELEASE_NOTES.md. See Github 3190 for more information.
• Rebuild the S3-related code and other changes necessary to build cleanly on github actions. See Github #3159 for more information.
• Fix the problems around ncdap_test/test_manyurls.c. See Github 3182 for more information.
• Fix bug in ncdump when printing FQNs (Issue 3184). See Github 3185 for more information.
• Update macOS github runners from macos-13 to macos-14, due to deprecation.
• Fix an error compiling netCDF with AWS-S3-SDK support using cmake. See Github 3155 for more information.
• Add new environmental logging variable for netCDF4 related logging subsystem, NC4LOGGING. If libnetcdf is compiled with logging enabled, logs can be enabled at runtime by setting this environmental variable to the desired log level.
• Update ncjson.[ch] and ncproplist.[ch]. Also fix references to old API. Also fix include/netcdf_ncjson.h and include/netcdf_proplist.h builds. See Github #3086 for more information.
• Refactor drc.c to move many of its purely utility functions into dutil.c. Also change the NC_mktmp signature. Change other files to match. See Github #3094 for more information.
• Provide an auxiliary function, ncaux_parse_provenance(), that allows users to parse the _NCProperties attribute into a collection of character pointers. See Github #3088 for more information.
• Fix a namespace problem in tinyxml2.cpp. Note that this is a visual studio problem hence use of _MSC_VER. Also turn off DAP4 tests against Hyrax server until DAP4 spec problems are fixed. See Github #3089 for more information.

What's Changed

• Merge v4.9.3 wellspring changes back upstream. by @WardF in Merge v4.9.3 wellspring changes back upstream.  #3084
• Provide an auxilliary function that allows users to parse the _NCProperties attribute. by @DennisHeimbigner in Provide an auxilliary function that allows users to parse the _NCProperties attribute. #3088
• Correct issue with .exe installer generation. by @WardF in Correct issue with .exe installer generation. #3096
• Correct a syntax error in previous packaging fix. by @WardF in Correct a syntax error in previous packaging fix.  #3097
• Fix SIGFPE with -0.0 values and quantization by @czender in Fix SIGFPE with -0.0 values and quantization #3093
• Give config.h a higher precedence. by @drwells in Give config.h a higher precedence. #3100
• Fix reported memory leak by @WardF in Fix reported memory leak #3102
• Fix bug in copying compound types with variable length fields. by @DennisHeimbigner in Fix bug in copying compound types with variable length fields. #3111
• Step 1 in splitting PR 3068 by @DennisHeimbigner in Step 1 in splitting PR 3068 #3086
• Create docker_regression_testing.yml by @WardF in Create docker_regression_testing.yml #3116
• Add a one-off test for java. by @WardF in Add a one-off test for java. #3117
• Step 2 in splitting PR 3068 by @DennisHeimbigner in Step 2 in splitting PR 3068 #3089
• Updated copyright by @WardF in Updated copyright #3119
• Fix various problems with S3 related code by @DennisHeimbigner in Fix various problems with S3 related code #3090
• Broken S3 implementation for netcdf files on non-AWS + Authenticated buckets by @mannreis in Broken S3 implementation for netcdf files on non-AWS + Authenticated buckets #3098
• Modify provenance check "_IsNetcdf4" to check for existence of "_NCProperties" by @DennisHeimbigner in Modify provenance check "_IsNetcdf4" to check for existence of "_NCProperties" #3125
• Fix pointer type on 64-bit Windows by @WardF in Fix pointer type on 64-bit Windows #3140
• Rebase of Remove strlcpy from libdispatch #3138 by @WardF in Rebase of #3138 #3142
• Remove strlcpy from libdispatch by @weiznich in Remove strlcpy from libdispatch #3138
• Updates for versioned H5Dread_chunk by @brtnfld in Updates for versioned H5Dread_chunk #3143
• Change order of operations so that data is not referenced after being freed. by @WardF in Change order of operations so that data is not referenced after being freed. #3146
• Fix Segmentation Fault when testing URLs with no path by @mannreis in Fix Segmentation Fault when testing URLs with no path #3095
• Only conditionally copy test files by @magnusuMET in Only conditionally copy test files #3133
• hdf5open.c: Handle null dataspace gracefully by @Dave-Allured in hdf5open.c: Handle null dataspace gracefully #3135
• CMake: correct the byterange flag by @jmckenna in CMake: correct the byterange flag #3131
• CMake: handle _INCLUDE_DIR not leveraged at compile time by @jmckenna in CMake: handle _INCLUDE_DIR not leveraged at compile time  #3132
• CMake: Bring nczarr dependency when enabling S3 in line with autotools by @WardF in CMake: Bring nczarr dependency when enabling S3 in line with autotools #3149
• Create PR to support refactor of drc.c code. by @DennisHeimbigner in Create PR to support refactor of drc.c code. #3094
• Patch Fix various problems with S3 related code #3090 - Fix and test S3 enabled builds by @mannreis in Patch #3090 - Fix and test S3 enabled builds #3122
• Update Software list with contribution. by @WardF in Update Software list with contribution. #3152
• Fix integer overflow vulnerability in NC string memory allocation by @dkjsone in Fix integer overflow vulnerability in NC string memory allocation #3153
• Remove unneeded dependency by @WardF in Remove unneeded dependency  #3158
• Address logging via environmental variable issues. by @WardF in Address logging via environmental variable issues. #3160
• Add failover default AWS region aws_default_region "us-east-1" by @WardF in Add failover default AWS region aws_default_region "us-east-1" #3164
• Added NC4LOGGING to RELEASE_NOTES.md by @WardF in Added NC4LOGGING to RELEASE_NOTES.md #3166
• Xattr header detection fix.wif by @WardF in Xattr header detection fix.wif #3167
• nc4hdf.c: Fix overwrite with zero-length attribute by @Dave-Allured in nc4hdf.c: Fix overwrite with zero-length attribute #3169
• CMake Builder Docs: document m4 dependency by @johnwparent in CMake Builder Docs: document m4 dependency #3173
• Fix an issue with using AWS S3 SDK and Cmake. by @WardF in Fix an issue with using AWS S3 SDK and Cmake.  #3174
• Updated Github MacOS runners from macos-13 to macos-14 by @WardF in Updated Github MacOS runners from macos-13 to macos-14 #3180
• Fix bug in ncdump when printing dimension FQN by @DennisHeimbigner in Fix bug in ncdump when printing dimension FQN #3185
• Fix the problems around ncdap_test/test_manyurls.c. by @DennisHeimbigner in Fix the problems around ncdap_test/test_manyurls.c. #3182
• General Cleanup to provide a clean base for future PRs. by @DennisHeimbigner in General Cleanup to provide a clean base for future PRs. #3159
• Cleanup RELEASE_NOTES.md by @DennisHeimbigner in Cleanup RELEASE_NOTES.md #3190
• ticket #TSP-8629412 bug fix by @dkjsone in ticket #TSP-8629412 bug fix #3191
• ncgen unsigned suffix fix by @jatkinson1000 in ncgen unsigned suffix fix #3189
• run_zero_len_att_test.sh: Improve error message by @Dave-Allured in run_zero_len_att_test.sh: Improve error message #3170
• Fix S3 internal configuration error by @gsjaardema in Fix S3 internal configuration error #3175
• Fix UBSan warnings about out-of-range assignment by @seanm in Fix UBSan warnings about out-of-range assignment #3210
• Clean up minor issues in DAP2+DAP4 code by @DennisHeimbigner in Clean up minor issues in DAP2+DAP4 code #3215
• Added codespell config file, fixed a bunch of spelling mistakes by @seanm in Added codespell config file, fixed a bunch of spelling mistakes #3211
• Fixed UBSan warnings about left shifts into the sign bit by @seanm in Fixed UBSan warnings about left shifts into the sign bit #3207
• Fix Issue with Numcodecs encoding problems by @DennisHeimbigner in Fix Issue with Numcodecs encoding problems #3201
• Initial basic editorconfig support by @seanm in Initial basic editorconfig support #3212
• Fixed UBSan warnings about offsetting a NULL pointer by @seanm in Fixed UBSan warnings about offsetting a NULL pointer #3206
• Modify the way xarray attribute sets are handled. by @DennisHeimbigner in Modify the way xarray attribute sets are handled. #3218
• Part 1 - Zarr consolidated metadata by @mannreis in Part 1 - Zarr consolidated metadata  #3219
• Part 2 - Zarr consolidated metadata by @mannreis in Part 2 - Zarr consolidated metadata #3220
• Part 3 - Zarr consolidated metadata by @mannreis in Part 3 - Zarr consolidated metadata #3221
• Part 4 - Zarr consolidated metadata by @mannreis in Part 4 - Zarr consolidated metadata #3222
• Part 5 - Zarr consolidated metadata by @mannreis in Part 5 - Zarr consolidated metadata #3223
• Part 6 - Zarr consolidated metadata by @mannreis in Part 6 - Zarr consolidated metadata #3224
• Part 7 - Zarr consolidated metadata by @mannreis in Part 7 - Zarr consolidated metadata #3225
• Initial consolidation of global state by @DennisHeimbigner in Initial consolidation of global state #3197
• See if we can add 'dash' shell to packages installed. by @WardF in See if we can add 'dash' shell to packages installed. #3235
• Fix source directory macro for FetchContent support by @WardF in Fix source directory macro for FetchContent support #3234
• Fix H5FD_class_t problems by @DennisHeimbigner in Fix H5FD_class_t problems #3237
• Document Consolidated Metadata by @mannreis in Document Consolidated Metadata #3231
• Clean up treeview in doxygen-generated documentation by @WardF in Clean up treeview in doxygen-generated documentation #3245
• Fix parallel hdf5 2.0.0 by @WardF in Fix parallel hdf5 2.0.0 #3247
• Add extra failure handling to the daos inferencing by @DennisHeimbigner in Add extra failure handling to the daos inferencing #3238
• Fixed UBSan warning, added missing clamping for text case by @seanm in Fixed UBSan warning, added missing clamping for text case #3209
• ncs3sdk_aws.cpp: remove duplicate function by @mannreis in ncs3sdk_aws.cpp: remove duplicate function #3248
• Regularize, cleanup, and refactor various AWS features by @DennisHeimbigner in Regularize, cleanup, and refactor various AWS features #3229
• Update netcdf-test-action to @v2 by @WardF in Update netcdf-test-action to @v2 #3252
• Updated docker-based regression testing by @WardF in Updated docker-based regression testing #3253
• Zarr: Error logging improvement by @mannreis in Zarr: Error logging improvement #3250
• fixed make distclean by @edhartnett in fixed make distclean #3256
• fixed warning by @edhartnett in fixed warning #3258
• Fixed UBSan warnings about unaligned memory access by @seanm in Fixed UBSan warnings about unaligned memory access #3208
• Zarr csl fully by @mannreis in Zarr csl fully #3241
• Fix regression reported in AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables not read for S3/Zarr access #3259 by @mannreis in Fix regression reported in #3259 #3263
• allow .ncrc loading of user defined format by @edhartnett in allow .ncrc loading of user defined format  #3264
• Quote path parameter in shell command during isdaoscontainer by @larsgeb in Quote path parameter in shell command during isdaoscontainer #3196
• AI Guidelines by @WardF in AI Guidelines #3297

New Contributors

• @drwells made their first contribution in Give config.h a higher precedence. #3100
• @jmckenna made their first contribution in CMake: correct the byterange flag #3131
• @dkjsone made their first contribution in Fix integer overflow vulnerability in NC string memory allocation #3153
• @jatkinson1000 made their first contribution in ncgen unsigned suffix fix #3189
• @larsgeb made their first contribution in Quote path parameter in shell command during isdaoscontainer #3196

Full Changelog: v4.9.3...v4.10.0

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This discussion was created from the release v4.10.0.

[Dave-Allured]

Wow, there is a lot here. Thanks!

Which older versions of HDF5 have you tested this new release against, if any?

[WardF]

@Dave-Allured We test against 1.12x, 1.14.x and now 2.x (internally, I will be pushing out an update to netcdf-test-action to incorporate 2.x into the Github action). I also test against 1.10.x internally, but including that in the Github Action test matrix really causes thinks to explode, and for the other NSF Unidata projects to remind me that our Github Runner pool is a shared resource XD. Fair enough.