Compound datasets written with default libver bounds (datatype message
version 1, i.e. plain h5py.File(path, 'w')) could not be read: the v1 member
layout has 28 bytes of legacy array fields after the byte offset
(dimensionality 1, reserved 3, permutation 4, reserved 4, four sizes 16) and
the parser skipped 24, so every following member was read 4 bytes off. v2 was
also wrong: it keeps the 8-byte name padding and has no array fields.
Found by adding a default-libver axis to the h5py-generated-file tests (HDF5
2.0 raised the default low bound to 1.8, so "default" files are a distinct
format path from libver='latest'). Adds byte-level v1/v2 regression tests, a
truncation test, and fuzz corpus seeds for v1 compound and native complex.
Co-Authored-By: Claude Fable 5.1 <[email protected]>
Class 11 (datatype version 5) properties are a single base floating-point
datatype message, not a compound-style member list. The old parser read the
base type's bytes as member names, yielding a garbage datatype, and failed
with UnexpectedEof when a complex type was nested in a compound.
Parse the base type and surface the type as the equivalent {r, i} compound
(the shape h5py writes for numpy complex dtypes), with a size check against
the base type. Covered by byte-level tests taken from HDF5 2.0 output and an
h5py end-to-end test (writer_h5py_tests is now 27/27 against HDF5 2.0.0).
Found while validating a user report of InvalidDatatypeVersion
{ class: 6, version: 5 } against v2.1.0 (already fixed on main in a13ff51,
never released). Add docs/known-issues.md recording that report, this bug,
the open reference-v4 gap and a gpu_tests parallel-run hang; credit the
reporter in the changelog.
Co-Authored-By: Claude Fable 5.1 <[email protected]>
