* 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.
* Pure `git merge --squash smart_holder` (no manual interventions).
* Remove ubench/ directory.
* Remove include/pybind11/smart_holder.h
* [ci skip] smart_ptrs.rst updates [WIP/unfinished]
* [ci skip] smart_ptrs.rst updates continued; also updating classes.rst, advanced/classes.rst
* Remove README_smart_holder.rst
* Restore original README.rst from master
* [ci skip] Minimal change to README.rst, to leave a hint that this is pybind11v3
* [ci skip] Work in ChatGPT suggestions.
* Change macro name to PYBIND11_RUN_TESTING_WITH_SMART_HOLDER_AS_DEFAULT_BUT_NEVER_USE_IN_PRODUCTION_PLEASE
* Add a note pointing to the holder reinterpret_cast.
* Incorporate suggestion by @virtuald: https://github.com/pybind/pybind11/pull/5542#discussion_r1967000989
* Systematically change most py::class_ to py::classh under docs/
* Remove references to README_smart_holder.rst
This should have been part of commit eb550d03d3.
* [ci skip] Fix minor oversight (``class_`` -> ``py::class_``) noticed by chance.
* [ci skip] Resolve suggestion by @virtuald
https://github.com/pybind/pybind11/pull/5542#discussion_r1969940605
* [ci skip] Apply suggestions by @timohl (thanks!)
* https://github.com/pybind/pybind11/pull/5542#discussion_r1970714551
* https://github.com/pybind/pybind11/pull/5542#discussion_r1971315329
* https://github.com/pybind/pybind11/pull/5542#discussion_r1971322821
* Replace `classh : class_` inhertance with `using`, as suggested by @henryiii
https://github.com/pybind/pybind11/pull/5542#issuecomment-2689034104
* Revert "Systematically change most py::class_ to py::classh under docs/"
This reverts commit ac9d31e13f.
* docs: focus on py::smart_holder instead of py::classh
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
* Restore minor general fixes that got lost when ac9d31e13f was reverted.
* Remove `- smart_holder` from list of branches in all .github/workflows
* Extend classh note to explain whitespace noise motivation.
* Suggest `py::smart_holder` for "most situations for safety"
* Add back PYBIND11_HAS_INTERNALS_WITH_SMART_HOLDER_SUPPORT
This define was
* introduced with https://github.com/pybind/pybind11/pull/5286
* removed with https://github.com/pybind/pybind11/pull/5531
It is has been in use here:
* f02a2b7653/pybind11_protobuf/native_proto_caster.h (L89-L101)
Currently pybind11 unit tests for the two holder caster backwards compatibility traits
* `copyable_holder_caster_shared_ptr_with_smart_holder_support_enabled`
* `move_only_holder_caster_unique_ptr_with_smart_holder_support_enabled`
are missing.
* Add py::trampoline_self_life_support to all trampoline examples under docs/.
Address suggestion by @timohl:
* https://github.com/pybind/pybind11/pull/5542#issuecomment-2686452062
Add to the "please think twice" note: the overhead for safety is likely in the noise.
Also fix a two-fold inconsistency introduced by revert-commit 1e646c91b4:
1.
py::trampoline_self_life_support is mentioned in a note, but is missing in the example right before.
2.
The section starting with
To enable safely passing a ``std::unique_ptr`` to a trampoline object between
is obsolete.
* Fix whitespace accident (indentation) introduced with 1e646c91b4
Apparently the mis-indentation was introduced when resolving merge conflicts for what became 1e646c91b4
* WHITESPACE CHANGES ONLY in README.rst (list of people that made significant contributions)
* Add Ethan Steinberg to list of people that made significant contributions (for completeness, unrelated to smart_holder work).
* [ci skip] Add to list of people that made significant contributions: major and/or influential contributors to smart_holder branch
* #2904 by @rhaschke was merged on Mar 16, 2021
* #3012 by @rhaschke was merged on May 28, 2021
* #3039 by @jakobandersen was merged on Jun 29, 2021
* #3048 by @Skylion007 was merged on Jun 18, 2021
* #3588 by @virtuald was merged on Jan 3, 2022
* #3633 by @wangxf123456 was merged on Jan 25, 2022
* #3635 by @virtuald was merged on Jan 26, 2022
* #3645 by @wangxf123456 was merged on Jan 25, 2022
* #3796 by @wangxf123456 was merged on Mar 10, 2022
* #3807 by @wangxf123456 was merged on Mar 18, 2022
* #3838 by @wangxf123456 was merged on Apr 15, 2022
* #3929 by @tomba was merged on May 7, 2022
* #4031 by @wangxf123456 was merged on Jun 27, 2022
* #4343 by @wangxf123456 was merged on Nov 18, 2022
* #4381 by @wangxf123456 was merged on Dec 5, 2022
* #4539 by @wangxf123456 was merged on Feb 28, 2023
* #4609 by @wangxf123456 was merged on Apr 6, 2023
* #4775 by @wangxf123456 was merged on Aug 3, 2023
* #4921 by @iwanders was merged on Nov 7, 2023
* #4924 by @iwanders was merged on Nov 6, 2023
* #5401 by @msimacek was merged on Oct 8, 2024
Co-authored-by: Aaron Gokaslan <aaronGokaslan@gmail.com>
Co-authored-by: Dustin Spicuzza <dustin@virtualroadside.com>
Co-authored-by: Ivor Wanders <iwanders@users.noreply.github.com>
Co-authored-by: Jakob Lykke Andersen <Jakob@caput.dk>
Co-authored-by: Michael Šimáček <michael.simacek@oracle.com>
Co-authored-by: Robert Haschke <rhaschke@users.noreply.github.com>
Co-authored-by: Tomi Valkeinen <tomi.valkeinen@iki.fi>
Co-authored-by: Xiaofei Wang <6218006+wangxf123456@users.noreply.github.com>
---------
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: Aaron Gokaslan <aaronGokaslan@gmail.com>
Co-authored-by: Dustin Spicuzza <dustin@virtualroadside.com>
Co-authored-by: Ivor Wanders <iwanders@users.noreply.github.com>
Co-authored-by: Jakob Lykke Andersen <Jakob@caput.dk>
Co-authored-by: Michael Šimáček <michael.simacek@oracle.com>
Co-authored-by: Robert Haschke <rhaschke@users.noreply.github.com>
Co-authored-by: Tomi Valkeinen <tomi.valkeinen@iki.fi>
Co-authored-by: Xiaofei Wang <6218006+wangxf123456@users.noreply.github.com>
