* Revert type hint changes to int_ and float_
These two types do not support casting from int-like and float-like types.
* Fix tests
* Add a custom py::float_ caster
The default py::object caster only works if the object is an instance of the type.
py::float_ should accept python int objects as well as float.
This caster will pass through float as usual and cast int to float.
The caster handles the type name so the custom one is not required.
* style: pre-commit fixes
* Fix name
* Fix variable
* Try satisfying the formatter
* Rename test function
* Simplify type caster
* Fix reference counting issue
---------
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* Avoid heap allocation for function calls with a small number of arguments
We don't have access to llvm::SmallVector or similar, but given the
limited subset of the `std::vector` API that
`function_call::args{,_convert}` need and the "reserve-then-fill"
usage pattern, it is relatively straightforward to implement custom
containers that get the job done.
Seems to improves time to call the collatz function in
pybind/pybind11_benchmark significantly; numbers are a little noisy
but there's a clear improvement from "about 60 ns per call" to "about
45 ns per call" on my machine (M4 Max Mac), as measured with
`timeit.repeat('collatz(4)', 'from pybind11_benchmark import
collatz')`.
* clang-tidy
* more clang-tidy
* clang-tidy NOLINTBEGIN/END instead of NOLINTNEXTLINE
* forgot to increase inline size after removing std::variant
* constexpr arg_vector_small_size, use move instead of swap to hopefully clarify second_pass_convert
* rename test_embed to test_low_level
* rename test_low_level to test_with_catch
* Be careful to NOINLINE slow paths
* rename array/vector members to iarray/hvector. Move comment per request. Add static_asserts for our untagged union implementation per request.
* drop is_standard_layout assertions; see https://github.com/pybind/pybind11/pull/5824#issuecomment-3308616072
* Use thread_local instead of thread_specific_storage for internals mangement
thread_local is faster.
* Make the pp manager a singleton.
Strictly speaking, since the members are static, the instances must also be singletons or this wouldn't work. They already are, but we can make the class enforce it to be more 'self-documenting'.
* Use thread_local for loader_life_support to improve performance
As explained in a new code comment, `loader_life_support` needs to be
`thread_local` but does not need to be isolated to a particular
interpreter because any given function call is already going to only
happen on a single interpreter by definiton.
Performance before:
- on M4 Max using pybind/pybind11_benchmark unmodified repo:
```
> python -m timeit --setup 'from pybind11_benchmark import collatz' 'collatz(4)'
5000000 loops, best of 5: 63.8 nsec per loop
```
- Linux server:
```
python -m timeit --setup 'from pybind11_benchmark import collatz' 'collatz(4)' (pytorch)
2000000 loops, best of 5: 120 nsec per loop
```
After:
- M4 Max:
```
python -m timeit --setup 'from pybind11_benchmark import collatz' 'collatz(4)'
5000000 loops, best of 5: 53.1 nsec per loop
```
- Linux server:
```
> python -m timeit --setup 'from pybind11_benchmark import collatz' 'collatz(4)' (pytorch)
2000000 loops, best of 5: 101 nsec per loop
```
A quick profile with perf shows that pthread_setspecific and pthread_getspecific are gone.
Open questions:
- How do we determine whether we can safely use `thread_local`? I see
concerns about old iOS versions on
https://github.com/pybind/pybind11/pull/5705#issuecomment-2922858880
and https://github.com/pybind/pybind11/pull/5709; is there anything
else?
- Do we have a test that covers "function called in one interpreter
calls a C++ function that causes a function call in another
interpreter"? I think it's fine, but can it happen?
- Are we happy with what we think will happen in the case where
multiple extensions compiled with and without this PR interoperate?
I think it's fine -- each dispatch pushes and cleans up its own
state -- but a second opinion is certainly welcome.
* Remove PYBIND11_CAN_USE_THREAD_LOCAL
* clarify comment
* Simplify loader_life_support TLS storage
Replace the `fake_thread_specific_storage` struct with a direct
thread-local pointer managed via a function-local static:
static loader_life_support *& tls_current_frame()
This retains the "stack of frames" behavior via the `parent` link. It also
reduces indirection and clarifies intent.
Note: this form is C++11-compatible; once pybind11 requires C++17, the
helper can be simplified to:
inline static thread_local loader_life_support *tls_current_frame = nullptr;
* loader_life_support: avoid duplicate tls_current_frame() calls
Replace repeated calls with a single local reference:
auto &frame = tls_current_frame();
This ensures the thread_local initialization guard is checked only once
per constructor/destructor call site, avoids potential clang-tidy
complaints, and makes the code more readable. Functional behavior is
unchanged.
* Add REMINDER for next version bump in internals.h
---------
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* pytypes.h: constrain accessor::operator= templates so that they do not match calls that should use the special member functions.
Found by an experimental, new clang-tidy check. While we may not know the exact design decisions now, it seems unlikely that the special members were deliberately meant to not be selected (for otherwise they could have been defined differently to make this clear). Rather, it seems like an oversight that the operator templates win in overload resolution, and we should restore the intended resolution.
* Use C++11-compatible facilities
* Use C++11-compatible facilities
* style: pre-commit fixes
---------
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* Make function_record type subinterpreter safe
* Get rid of static state in implicit conversion
* style: pre-commit fixes
* Fix lambda
* Bump ABI because we added an internals member
* Set __module__ on the type instance to get rid of DepricationWarning
* Work around internal compiler error in CUDA by not using typedef
hopefully
* Make clang-tidy happy
* Use the same __module__ as pybind11_static_property
* style: pre-commit fixes
* Oops, find-replace error
* style: pre-commit fixes
* Move the once initialization to happen more behind the scenes
* Oops, need those casts...
* Undo implicit conversion change, will do a separate PR
* Use local_internals for function_record pointer to avoid ABI bump
* style: pre-commit fixes
* Get rid of this auto for readability
* Change back to using unqualified tp_name, set __module__ attribute, explicitly add Py_TPFLAGS_HEAPTYPE → does not resolve DeprecationWarning :-(
* Revert "Change back to using unqualified tp_name, set __module__ attribute, explicitly add Py_TPFLAGS_HEAPTYPE → does not resolve DeprecationWarning :-("
This reverts commit 9ccd6de9b7.
* Add Py_TPFLAGS_HEAPTYPE to be explicit (more readable).
* Remove obsolete PYBIND11_WARNING_DISABLE_...
* Make tp_plainname_impl, tp_qualname_impl more DRY
* Change PYBIND11_INTERNAL_MODULE_NAME → PYBIND11_DUMMY_MODULE_NAME
* Add a long comment to explain the tp_qualname_impl workaround.
* Rename local_internals::function_record → function_record_py_type
---------
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* Failing unit test
* Potential fix for the issue of re-importing a multi-phase module
- When a module is successfully imported and exec'd, save its handle in a dict in the interpreter state
- Use a special Py_mod_create slot to look in the cache and return the cached handle if it is in the cache
- Don't re-run the user exec function if the module is in the interpreter's cache (implying it was already successfully imported)
* Oops, need to inline these.
* Clang-Tidy fixes
* Oops, debug code
* Add xfail for this GraalPy bug
* Remove static from these function defs, it was a cut-and-paste error in the first place.
* Fix test comment
* Proper error handling
* Oops
* Split up this line, but still just ignore failure .. if the module doesn't have the right properties to check the cache then just allow exec to run.
* Clean up - already looked up the name, just use that.
* Some compilers complain if the pointer isn't taken here, weird.
* Allow attribute errors to be thrown here, will be converted to import errors by the exception handler.
* Remove bogus incref, unconditionally expect a __spec__.name on the module
* Add PR to test comment
* style: pre-commit fixes
---------
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* Replace static bool with thread-specific-storage to make this code sub-interpreter and free-threading safe.
* Make sure there is only one tss value in existence for this.
The previous code had multiple (one for every type pair, as this is a template function), which may have posed a problem for some platforms.
* Make set_flag in implicitly_convertible() non-copyable/movable
set_flag is an RAII guard for a thread-specific reentrancy flag.
Copying or moving it would risk double-resetting or rearming the flag,
breaking the protection. Disable copy/move constructors and assignment
operators to make this explicit.
* Minor cleanup to avoid venturing into UB territory.
* Experiment: Disable `~thread_specific_storage()` body when using GraalPy.
* Try the suggestion to only call TSS_free if the python interpreter is still active.
* Add IsFinalizing check
* Put this back to having a per-template-instance static
---------
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* Seems like 3.12 has concurrency issues when creating a subinterpreter, easiest workaround is just to lock during it.
* Only need this for PER_INTERPRETER_GIL
C++20 can be enabled while the C++ runtime is still much older so use the feature macro to check for it.
For example, we are using the latest clang with c++23 on SLES, while the gcc version is 7.
When compiling an application using pybind11 3.0.0, GCC 13.3.0 and
python 3.11.13 the following warning is emitted [1]:
In function 'PyObject* PyCFunction_GET_SELF(PyObject*)',
inlined from 'void pybind11::cpp_function::initialize_generic(unique_function_record&&, const char*, const std::type_info* const*, pybind11::size_t)' at /opt/conda/lib/python3.11/site-packages/pybind11/include/pybind11/pybind11.h:605:30:
/opt/conda/include/python3.11/cpython/methodobject.h:50:16: error: potential null pointer dereference [-Werror=null-dereference]
50 | return _Py_NULL;
| ^~~~~~~~
It stems form the fact that PyCFunction_GET_SELF can return a nullptr.
Let's fail in this case.
[1]: https://gitlab.com/tango-controls/pytango/-/jobs/10671972312#L570
* Update docs/changelog.md and change version to v3.0.0 (final)
* [skip ci] Add `|SPEC 4 — Using and Creating Nightly Wheels|` badge in main README.rst
* Add overload to enable `.def(py::init(&rtrn_shcp))`. Also uncomment `.def(py::init(&rtrn_uqcp))` and `.def(py::init(&rtrn_udcp))`, which happen to work already (not sure what change in the past made those work).
* Introduce `construct_from_shared_ptr()` helper for DRY-ness.
* Revert PR #5700 production code change (pybind11/detail/struct_smart_holder.h).
```
git checkout b19489145b2c7a117138632d624809dfb3b380bb~1 include/pybind11/detail/struct_smart_holder.h
```
* Introduce `get_internals().get_memory_guarded_delete()`
* [skip ci] Only pass around `memory::get_guarded_delete` function pointer.
* [skip ci] Change a variable name for internal consistency. Add 3 x NOTE: PYBIND11_INTERNALS_VERSION needs to be bumped if changes are made to this struct.
* Add comment: get_internals().get_memory_guarded_delete does not need with_internals()
* Traverse all DSOs to find memory::guarded_delete with matching RTTI.
* Add nullptr check to dynamic_cast overload.
Suggested by ChatGPT for these reasons:
* Prevents runtime RTTI lookups on nullptr.
* Helps avoid undefined behavior if users pass in nulls from failed casts or optional paths.
* Ensures consistent return value semantics and no accidental access to vtable.
* Improve smart_holder unique_ptr deleter compatibility checks across DSOs:
* Replace RTTI-based detection of std::default_delete<T> with a constexpr check to avoid RTTI reliance
* Add type_info_equal_across_dso_boundaries() fallback using type_info::name() for RTTI equality across macOS DSOs
* Rename related flags and functions for clarity (e.g., builtin → std_default)
* Improves ABI robustness and clarity of ownership checks in smart_holder
* Trivial renaming for internal consistency: builtin_delete → std_default_delete
* Add get_trampoline_self_life_support to detail::type_info (passes local testing).
* Polish previous commit slightly.
* [skip ci] Store memory::get_guarded_delete in `detail::type_info` instead of `detail::internals` (no searching across DSOs required).
* Revert change suggested by ChatGPT. After double-checking, ChatGPT agrees this isn't needed.
* Minor polishing.
* add support for const pointers in smart pointers
* use c++11 compatible code
* add template parameter in test
* Make the const-removal clearly visible. This simplifies the production code changes significantly.
For background see: https://claude.ai/share/4085d9ab-a859-44cc-bb56-450e472f817a
* test without leaks
* add namespace for test
* rename test
* fix test compilation
* using namespace test_const_only_smart_ptr;
* fix smartptr in test
* smaller test body
* move test
* style: pre-commit fixes
---------
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* chore: handle null for `py::scoped_critical_section`
* test: add tests for `py::scoped_critical_section`
* test: use assert instead of REQUIRE
* feat: enable faulthandler for pytest
* chore: use `__has_include(<barrier>)`
* fix: fix segmentation fault in test
* fix: test critical_section for no-gil only
* test: run new tests only
* test: ensure non-empty test selection
* fix: fix test critical_section
* fix: change Python 3.14.0b1/2 xfail tests to non-strict
* test: trigger gc manually
* test: mark xfail to `DynamicClass`
* Use `namespace test_scoped_critical_section_ns` (standard approach to guard against name clashes).
* Simplify changes in pybind11/critical_section.h and add test_nullptr_combinations()
* test: disable Python devmode in pytest
* test: add comprehensive comments for the tests
* test: add a summary comment for tests
* refactor: simpler impl
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
---------
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* Refactor internals to use a holder that manages the PP
* Refactor internals to use a holder that manages the PP
* Fix cleanup/destruction issues.
* Fix one more destruction issue
Should now just be able to delete the internals PP on destruction
* Make clang-tidy happy
* Try to fix exception translators issue on certain platforms
Also fix a couple more pedantic warings
* Fix test, after internals is free'd it can come back at the same address
So instead, just make sure it was zero'd and don't try to compare the addresses.
Also a little code cleanup
* Comment tweak [skip ci]
* Switch to ifdef instead of if
* Re-enable subinterpreters in iOS
* style: pre-commit fixes
* Oops, this snuck in on merge
* fix: bump ABI version to 10
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
---------
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* test: Added test case for visibility of common symbols across shared libraries
* style: pre-commit fixes
* tests: cmake target name fix
* tests: Added visibility test to ci
* tests: set the default visibility to hidden
* prototype/proof-of-concept fix: PYBIND11_EXPORT_GUARDED_DELETE
* Fix silly oversight: actually use PYBIND11_EXPORT_GUARDED_DELETE
* Update struct_smart_holder.h
* style: pre-commit fixes
* Update include/pybind11/detail/struct_smart_holder.h
* Update struct_smart_holder.h
* ci: fix addition to reusable-standard.yml
* Update CMakeLists.txt
* refactor: rename tests to test_cross_module_rtti
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---------
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* fix future type hints
Signed-off-by: Michael Carlstrom <rmc@carlstrom.com>
* style: pre-commit fixes
* remove unused var
Signed-off-by: Michael Carlstrom <rmc@carlstrom.com>
* remove union_helper
Signed-off-by: Michael Carlstrom <rmc@carlstrom.com>
* fix speelling error
Signed-off-by: Michael Carlstrom <rmc@carlstrom.com>
* base case for union_concat
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* style: pre-commit fixes
* add case for one descr
Signed-off-by: Michael Carlstrom <rmc@carlstrom.com>
* weakref and final test
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* Add acrpss_version_type_hint_checker
Signed-off-by: Michael Carlstrom <rmc@carlstrom.com>
* cleanup
Signed-off-by: Michael Carlstrom <rmc@carlstrom.com>
* style: pre-commit fixes
* remove test.pyi
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* use new unions and add fixture
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* timohl suggested cleanup
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* style: pre-commit fixes
* add missing auto
Signed-off-by: Michael Carlstrom <rmc@carlstrom.com>
* style: pre-commit fixes
* move operator| def
---------
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* feat: scoped_critical_section
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* refactor: pull out to file
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* style: pre-commit fixes
* fix: GIL code in some compilers
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* fix: move to correct spot
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---------
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* refactor: use CPython macros to construct `PYBIND11_VERSION_HEX`
* docs: update release guide
* tests: add test to keep version values in sync
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* style: pre-commit fixes
* test: update version test
* test: update version test
* test: update version test
* chore: update code comments
* Update docs/release.rst
---------
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* First draft a subinterpreter embedding API
* Move subinterpreter tests to their own file
* Migrate subinterpreter tests to use the new embedded class.
* Add a test for moving subinterpreters across threads for destruction
And find a better way to make that work.
* Code organization
* Add a test which shows demostrates how gil_scoped interacts with sub-interpreters
* Add documentation for embeded sub-interpreters
* Some additional docs work
* Add some convenience accessors
* Add some docs cross references
* Sync some things that were split out into #5665
* Update subinterpreter docs example to not use the CPython api
* Fix pip test
* style: pre-commit fixes
* Fix MSVC warnings
I am surprised other compilers allowed this code with a deleted move ctor.
* Add some sub-headings to the docs
* Oops, make_unique is C++14 so remove it from the tests.
* I think this fixes the EndInterpreter issues on all versions.
It just has to be ifdef'd because it is slightly broken on 3.12, working well on 3.13, and kind of crashy on 3.14beta. These two verion ifdefs solve all the issues.
* Add a note about exceptions.
They contain Python object references and acquire the GIL, that means they are a danger with subinterpreters!
* style: pre-commit fixes
* Add try/catch to docs examples to match the tips
* Python 3.12 is very picky about this first PyThreadState
Try special casing the destruction on the same thread.
* style: pre-commit fixes
* Missed a rename in a ifdef block
* I think this test is causing problems in 3.12, so try ifdefing it to see if the problems go away.
* style: pre-commit fixes
* Document the 3.12 constraints with a warning
* Apply suggestions from code review
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* ci: add cpptest to the clang-tidy job
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* noexcept move operations
* Update include/pybind11/subinterpreter.h
std::memset
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---------
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* Move common code from PYBIND11_MODULE and PYBIND11_EMBEDDED_MODULE into one macro
The difference between the two is really small, almost all of the code was the same.
* Use a macro to make the forward decl correct and reduce code duplication
* Oops, extra semicolon
* Split up the macro into two so we can avoid the redundant decl
* Fix Python 3.8 type hints and add module prefix
These type hints are invalid in Python 3.8.
Add `typing.` prefix to remove ambiguity.
* style: pre-commit fixes
* Add module prefix to Union
* Rename macros
* Improve comment
* Comment out 3.8 type hint macros
Fixing this issue in Python 3.8 will require updating lots of tests. This can be added in a further pull request.
* Add Iterable module prefix
* Add module prefix to Iterator
* Add module prefix to Callable
* Re-add accidentally deleted brackets
* Add module prefix to Optional
* Add module prefix to Final
* Add module prefix to ClassVar
* Add module prefix to TypeGuard
* Add module prefix to TypeIs
* Add module prefix to NoReturn
* Add module prefix to Never
* Add module prefix to Literal
* Add module prefix to Callable
* Add module prefix to Sequence
* Add module prefix to Iterator
* style: pre-commit fixes
* Remove type hint macros
* style: pre-commit fixes
---------
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* Squashed prepv300/manuscript — 30b9c268aeb98308ea42aaccfd5fe454e173c6fc — 2025-03-30 14:56:03 -0700 [skip ci]
[Browse prepv300/manuscript tree](30b9c268ae)
[Browse prepv300/manuscript commits](30b9c268ae/)
* docs: update changelog
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* docs: upgrade guide CMake suggestions
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* Explain type_caster_enum_type_enabled, copyable_holder_caster_shared_ptr_with_smart_holder_support_enabled, move_only_holder_caster_unique_ptr_with_smart_holder_support_enabled in Upgrade guide.
* Add a small section for py::bind_vector, py::bind_map & py::smart_holder
* Fix tiny oversight: Reference back to the current release v2.13 (not v2.12)
* Remove sentence: Using self._pybind11_conduit_v1_() ... should keep extension compatibility.
This isn't true, because we also modernized `PYBIND11_PLATFORM_ABI_ID`
(which I believe was absolutely necessary). I think it'll be too complicated
to explain that here, and there is a mention in the Upgrade guide.
* Changelog: combine #4953 and #5439
* Trivial whitespace/formatting fixes/enhancements.
* chore: add more to deprecation page
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* docs: update for recent additions
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* docs: fixes and set rc1 version
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* fix: support rc versions
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* Undo erroneous copilot change: We need to use `detail::enable_if_t`, for compatibility with C++11 and C++14.
* Empty lines cleanup.
* Rewording of "CMake support now defaults to ..." paragraph.
* Add missing backticks in upgrade guide.
* Try :ref:deprecated instead of :doc:deprecated
* docs: last bit of polish
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* Piggy-back trivial whitespace cleanup that was missed in PR #5669
---------
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