The wheel is cp312-abi3, so it loads on 3.13 unchanged — the pin that has to
move is the interpreter the parity venv is built with, since its whole point is
resembling what the image ships.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CDYRXGB8tW4NE7b91g7Kdb
- GIL policy gains the XSTEP exception (STEP/IGES hold it; RWStl releases).
- A new rule, learned three times the hard way: an unregistered type cannot be
a default argument, because nanobind converts defaults at binding time and
the failure is a bare std::bad_cast at import with no file or line.
- A section on matching upstream: what sigdiff exists for, why static analysis
cannot see instance methods, and why the app's suite cannot gate a single
increment.
- An OCCT 8.0 watchlist, so the 10E bump is a known quantity.
- S5 marked settled: no CSF_* resources needed in the wheel.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DfriM8XUkn7uYf5Dwe2xo6
Builds n3xd-ocp end to end and publishes 7.9.3.1.dev1 to the Gitea registry,
where it installs anonymously and passes its suite.
- occt/Dockerfile: OCCT 7.9.3 compiled once into a manylinux_2_28 builder
image (base digest + tarball sha256 pinned), Draw/VTK/Tk/Xlib/OpenGL off,
FreeType on, -O2 without fast-math or march=native. A final layer asserts
TKService/TKV3d exist with no libGL/libX11 DT_NEEDED, which is what lets the
app image drop libgl1/libx11-6. Mounted into, never built FROM.
- scikit-build-core + nanobind STABLE_ABI -> one cp312-abi3 extension that
registers every OCP.* submodule via PyImport_AddModule, so `import
OCP.TopoDS` needs no shim and cls.__module__ is right. Version <occt>.N is
asserted against the OCCT found, keeping occt_version() truthful.
- occt_handle.h: type caster for opencascade::handle<T> over OCCT's intrusive
refcount. Wrappers are non-owning instances holding exactly one handle in
their keep-alive list, reusing an existing wrapper so identity survives a
round trip. Transient constructors go through ocp_new (never nb::init<>,
which would let OCCT delete nanobind's storage); the caster refuses a
refcount-0 object rather than corrupt the heap. Verified under ASAN with no
memory-safety errors, plus an RSS bound over 50k create/destroy cycles.
- Sub-shapes are returned by value everywhere, making the TShape lifetime class
that segfaulted a process-global face memo unrepresentable.
- Standard_Failure derives RuntimeError, with ~20 concrete types dispatched on
the dynamic OCCT type (cad_pool marshals failures home by type name).
- Inc 0 surface: gp subset, TopAbs, TopoDS (+ downcasts), TopExp, TopLoc,
TopTools, BRep, BinTools, Poly, Standard. 34 of the app's 139 symbols.
- n3xd_ocp: additive APIs kept out of the OCP namespace so parity testing stays
meaningful. bintools (shape <-> bytes, GIL-free, byte-identical) and _debug.
Two findings worth the record, both verified against the stock wheel rather
than assumed: upstream binds __hash__ but leaves __eq__ at identity, which is
exactly what geom_memo.py's hash-bucket + IsSame scan is built around, so we
match it instead of "fixing" it; and BinTools can release the GIL after all, by
slurping the file-like object instead of bridging a streambuf that would call
back into Python.
Gate: BREP round-trips are byte-identical to cadquery-ocp-novtk across six
fixtures (the generator asserts stock idempotency first). That matters beyond
IPC — derive.py content-addresses BREP payloads by sha256 and stores the ref.
