Version 3.0.0 RC 1
Pre-releaseWhat's Changed
Since this is a large release, we are providing a release candidate to give projects time to test! We also now provide SPEC 4 nightly wheels. We are hoping to split up std.h; that work is approved to be added during the RC phase if it's ready in time. We expect the RC phase to last around a week.
Pybind11 3.0 includes an ABI bump, the first required bump in many years on Unix (Windows has had required bumps more often). This release contains the smart-holder branch, multi-phase init and subinterpreter support, py::native_enum, an interface to warnings, typing improvements, and more. CMake now defaults to FindPython mode. Please check our upgrade guide for more info on upgrading!
Support for Python 3.14, 3.14t, GraalPy, and PyPy 3.11 has been added, while legacy support for Python 3.7, PyPy 3.8/3.9, and CMake <3.15 has been removed. Most deprecated features have been kept for this release, but anything producing a warning in 3.0 may be removed in a future 3.x version. We also now have a deprecation page.
New Features:
- The
smart_holderbranch has been merged, enablingpy::class_<T, py::smart_holder>, which handles two-way conversion
withstd::unique_ptr<T>andstd::shared_ptr<T>(simultaneously), disowning a Python object being passed tostd::unique_ptr<T>, trampoline objects, andstd::enable_shared_from_this. #5542 - Changed
PYBIND11_MODULEmacro implementation to perform multi-phase module initialization (PEP 489) behind the scenes. #5574 - Support for sub-interpreters (both isolated (with separate GILs) and legacy (with a global GIL). Add the
py::multiple_interpreters::per_interpreter_gil()tag (or,py::multiple_interpreters::shared_gil()for legacy interpreter
support) toPYBIND11_MODULEcalls (as the third parameter) to indicate that a module supports running with sub-interpreters. #5564 - Changed
PYBIND11_EMBEDDED_MODULEmacro implementation to perform multi-phase module initialization (PEP 489) behind the scenes and to supportpy::mod_gil_not_used(),py::multiple_interpreters::per_interpreter_gil()andpy::multiple_interpreters::shared_gil(). #5665 and consolidate code #5670 - Added API in
pybind11/subinterpreter.hfor embedding sub-intepreters (requires Python 3.12+). #5666 py::native_enumwas added, for conversions between Python's native (stdlib) enum types and C++ enums. #5555- A
py::release_gil_before_calling_cpp_dtoroption (forpy::class_) was added to resolve the long-standing issue #1446. #5522 - Add
dtype::normalized_numanddtype::num_of. #5429 - Add support for
array_t<handle>andarray_t<object>. #5427 - Added
py::warningsnamespace withpy::warnings::warnandpy::warnings::new_warning_typethat provides the interface for
Python warnings. #5291 stl.hlist|set|map_casterwere made more user friendly: it is no longer necessary to explicitly convert Python iterables totuple(),
set(), ormap()in many common situations. #4686- The
array_casterin pybind11/stl.h was enhanced to support value types that are not default-constructible. #5305 pybind11/conduit/pybind11_platform_abi_id.hwas factored out, to maximize reusability ofPYBIND11_PLATFORM_ABI_ID(for other Python/C++ binding systems). #5375- Added support for finding pybind11 using pkgconf distributed on pypi. #5552
- Support
--extension-suffixon the pybind11 command. #5360 - Add semi-public API:
pybind11::detail::is_holder_constructedand update example forpybind11::custom_type_setupin documentation. #5669
New Features / fixes (typing):
- Added option for different arg/return type hints to
type_caster. Updatedstl/filesystemto use correct arg/return type hints. Updatedpybind11::typingto use correct arg/return type hints for nested types. #5450 - Updated type hint for
py::capsuletotype.CapsuleType. #5567 - Adds support for
typing.SupportsIntandtyping.SupportsFloat. UpdateFinalto be narrower type hint. Makestd::functionmatchCallabletype. Fixio_namebug inattr_with_type_hint. #5540 - Rework of arg/return type hints to support
.noconvert(). #5486 - Add
attr_with_typefor declaring attribute types andFinal,ClassVartype annotations. #5460 - Allow annotate methods with
py::pos_onlywhen only have theselfargument. Make arguments for auto-generated dunder methods positional-only. #5403 - Added
py::Argsandpy::KWArgsto enable custom type hinting of*argsand**kwargs(see PEP 484). #5357 - Switched to
numpy.typing.NDArrayandnumpy.typing.ArrayLike. #5212 - Use
numpy.object_instead ofobject. #5571 - Fix module type hint. #5469
- Fix Buffer type hint. #5662
- Added support for
collections.abcin type hints and convertible checks of STL casters andpy::buffer.
#5566 - Fix
typingandcollections.abctype hint ambiguity. #5663
Removals:
- Remove support for pybind11 v2 internals versions (4, 5, 6). (The internals version number has been bumped for pybind11 v3.) #5512 | #5530
- Remove
make_simple_namespace(added in 2.8.0, deprecated in 2.8.1). #5597 - Legacy-mode option
PYBIND11_NUMPY_1_ONLYhas been removed. #5595 - Add a deprecation warning to
.get_type(deprecated in pybind11 2.6 in 2020). #5596
Bug fixes:
- Set
__file__on submodules. #5584. Except on
embedded modules. #5650 - pybind11-bound functions are now pickleable. #5580
- Fix bug in
attr_with_type_hintto allow objects to be inattr_with_type_hint. #5576 - A
-Wmaybe-uninitializedwarning suppression was added inpybind11/eigen/matrix.h. #5516 PYBIND11_WARNING_POPwas incorrectly defined asPYBIND11_PRAGMA(clang diagnostic push). #5448PYBIND11_PLATFORM_ABI_ID(which is used in composingPYBIND11_INTERNALS_ID) was modernized to reflect actual ABI
compatibility more accurately. #4953 | #5439- Fix buffer protocol implementation. #5407
- Fix iterator increment operator does not skip first item. #5400
- When getting or deleting an element in a container bound by
bind_map, print the key inKeyErrorif it does not exist. #5397 pybind11::builtin_exceptionis now explicitly exported when linked to libc++. #5390- Allow subclasses of
py::argsandpy::kwargs. #5381 - Disable false-positive GCC 12 Bound Check warning. #5355
- fix: using
__cpp_nontype_template_argsinstead of__cpp_nontype_template_parameter_class. #5330 - Properly translate C++ exception to Python exception when creating Python buffer from wrapped object. #5324
- Update the dict when restoring pickles, instead of assigning a replacement dict. #5658
- Properly define
_DEBUGmacro to1instead of defining it without value. #5639 - Fix a missing time cast causing a compile error for newer ICC. #5621
- Change the behavior of the default constructor of
py::sliceto be equivalent to::in Python. #5620
Bug fixes (CMake):
- Enable FindPython mode by default, with a
COMPATmode that sets some of the old variables to ease transition. #5553 - Add an author warning that auto-calculated
PYTHON_MODULE_EXTENSIONmay not respectSETUPTOOLS_EXT_SUFFIXduring cross-compilation. #5495 - Don't strip with
CMAKE_BUILD_TYPENone. #5392 - Fix an issue with
NO_EXTRASaddingpybind11::windows_extrasanyway. #5378 - Fix issue with NEW/OLD message showing up. #5656
- Use CMake's warnings as errors if available (CMake 3.24+). #5612
- Add support for running pybind11's tests via presets in CMake 3.25+. #5655 and support
--fresh. #5668 - Restructure venv support to support
--fresh, make in build folder. #5668
Bug fixes (free-threading):
- Fix data race in free threaded CPython when accessing a shared static variable. #5494
- A free-threading data race in
all_type_info()was fixed. #5419 - Added exception translator specific mutex used with
try_translate_exceptionsin the free-threaded build for internal
locking. #5362
Internals:
- Consolidated all
PYBIND11_HAS_...feature macros intopybind11/detail/common.hto streamline backward compatibility checks and simplify internal refactoring. This change ensures consistent macro availability regardless of header inclusion order. #5647 pybind11/gil_simple.hwas factored out frompybind11/gil.h, so that it can easily be reused. #5614
Documentation:
- Improved
reference_internalpolicy documentation. #5528 - A new "Double locking, deadlocking, GIL" document was added. #5394
- Adds an answer (FAQ) for "What is a highly conclusive and simple way to find memory leaks?". #5340
- Add documenting for free-threading and subinterpreters. #5659
Tests:
- Download the final Catch2 2.x release if Catch download is requested. #5568
- Explicitly used
signed charfor two numpy dtype tests. As seen when compiling usingclangon Linux with the-funsigned-charflag. #5545 - Test PyPy3.11 in CI. #5534
- CI testing now includes
-Wwrite-strings -Wunreachable-code -Wpointer-arith -Wredundant-declsin some jobs. #5523 - Add nightly wheels to scientific-python's nightly wheelhouse. #5675
New and removed platforms:
- Support Python 3.14 (beta 1). #5646
- Added support for GraalPy Python implementation (https://github.com/oracle/graalpython). #5380
- Support for PyPy 3.11 added. #5508
- Support for PyPy 3.8 and 3.9 was dropped. #5578
- Support for Python 3.7 was removed. (Official end-of-life: 2023-06-27). #5191
- Support for CMake older than 3.15 removed. CMake 3.15-4.0 supported. #5304
- Use scikit-build-core for the build backend for the PyPI
pybind11. The CMake generation has been moved to the sdist->wheel step.
PYBIND11_GLOBAL_SDISThas been removed. #5598 and updated
docs/ci. #5676
New Contributors
- @varunagrawal made their first contribution in #5207
- @wenqing made their first contribution in #5208
- @rgommers made their first contribution in #5250
- @teo-tsirpanis made their first contribution in #5263
- @fred-sch made their first contribution in #5284
- @pwdcd made their first contribution in #5308
- @MarkusBauer made their first contribution in #4874
- @ObeliskGate made their first contribution in #5314
- @DWesl made their first contribution in #5326
- @vnlitvinov made their first contribution in #5324
- @BobbyRBruce made their first contribution in #5355
- @vfdev-5 made their first contribution in #5362
- @Hintay made their first contribution in #5378
- @gentlegiantJGC made their first contribution in #5381
- @sarlinpe made their first contribution in #5397
- @francesco-ballarin made their first contribution in #5396
- @J-M0 made their first contribution in #5448
- @timohl made their first contribution in #5450
- @jspricke made their first contribution in #5392
- @nikulpatel3141 made their first contribution in #5360
- @mattip made their first contribution in #5508
- @daizhirui made their first contribution in #5516
- @pganssle-google made their first contribution in #5545
- @b-pass made their first contribution in #5574
- @dyollb made their first contribution in #5617
- @nsoblath made their first contribution in #5624
Full Changelog: v2.13.6...v3.0.0rc1