* Use `multiprocessing` `start_method` `"forkserver"`
Alternative to PR #4305
* Add link to comment under PR #4105
* Unconditionally `pytest.skip("DEADLOCK")` for PyPy Windows
* Remove `SKIP_IF_DEADLOCK` entirely, for simplicity. Hopefully this PR will resolve the deadlocks for good.
* Add "In a nutshell" comment, in response to request by @EricCousineau-TRI
* Illustrate bug in functional.h
* style: pre-commit fixes
* Make functional casting more robust / add workaround
* Make function_record* casting even more robust
* See if this fixes PyPy issue
* It still fails on PyPy sadly
* Do not make new CTOR just yet
* Fix test
* Add name to ensure correctness
* style: pre-commit fixes
* Clean up tests + remove ifdef guards
* Add comments
* Improve comments, error handling, and safety
* Fix compile error
* Fix magic logic
* Extract helper function
* Fix func signature
* move to local internals
* style: pre-commit fixes
* Switch to simpler design
* style: pre-commit fixes
* Move to function_record
* style: pre-commit fixes
* Switch to internals, update tests and docs
* Fix lint
* Oops, forgot to resolve last comment
* Fix typo
* Update in response to comments
* Implement suggestion to improve test
* Update comment
* Simple fixes
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Aaron Gokaslan <aaronGokaslan@gmail.com>
* Add option to force the use of the PYPY GIL scoped acquire/release logic to support nested gil access, see https://github.com/pybind/pybind11/issues/1276 and https://github.com/pytorch/pytorch/issues/83101
* Apply suggestions from code review
* Update CMakeLists.txt
* docs: update upgrade guide
* Update docs/upgrade.rst
* All bells & whistles.
* Add Reminder to common.h, so that we will not forget to purge `!WITH_THREAD` branches when dropping Python 3.6
* New sentence instead of semicolon.
* Temporarily pull in snapshot of PR #4246
* Add `test_release_acquire`
* Add more unit tests for nested gil locking
* Add test_report_builtins_internals_keys
* Very minor enhancement: sort list only after filtering.
* Revert change in docs/upgrade.rst
* Add test_multi_acquire_release_cross_module, while also forcing unique PYBIND11_INTERNALS_VERSION for cross_module_gil_utils.cpp
* Hopefully fix apparently new ICC error.
```
2022-10-28T07:57:54.5187728Z -- The CXX compiler identification is Intel 2021.7.0.20220726
...
2022-10-28T07:58:53.6758994Z icpc: remark #10441: The Intel(R) C++ Compiler Classic (ICC) is deprecated and will be removed from product release in the second half of 2023. The Intel(R) oneAPI DPC++/C++ Compiler (ICX) is the recommended compiler moving forward. Please transition to use this compiler. Use '-diag-disable=10441' to disable this message.
2022-10-28T07:58:54.5801597Z In file included from /home/runner/work/pybind11/pybind11/include/pybind11/detail/../detail/type_caster_base.h(15),
2022-10-28T07:58:54.5803794Z from /home/runner/work/pybind11/pybind11/include/pybind11/detail/../cast.h(15),
2022-10-28T07:58:54.5805740Z from /home/runner/work/pybind11/pybind11/include/pybind11/detail/../attr.h(14),
2022-10-28T07:58:54.5809556Z from /home/runner/work/pybind11/pybind11/include/pybind11/detail/class.h(12),
2022-10-28T07:58:54.5812154Z from /home/runner/work/pybind11/pybind11/include/pybind11/pybind11.h(13),
2022-10-28T07:58:54.5948523Z from /home/runner/work/pybind11/pybind11/tests/cross_module_gil_utils.cpp(13):
2022-10-28T07:58:54.5949009Z /home/runner/work/pybind11/pybind11/include/pybind11/detail/../detail/internals.h(177): error #2282: unrecognized GCC pragma
2022-10-28T07:58:54.5949374Z PYBIND11_TLS_KEY_INIT(tstate)
2022-10-28T07:58:54.5949579Z ^
2022-10-28T07:58:54.5949695Z
```
* clang-tidy fixes
* Workaround for PYPY WIN exitcode None
* Revert "Temporarily pull in snapshot of PR #4246"
This reverts commit 23ac16e859150f27fda25ca865cabcb4444e0770.
* Another workaround for PYPY WIN exitcode None
* Clean up how the tests are run "run in process" Part 1: uniformity
* Clean up how the tests are run "run in process" Part 2: use `@pytest.mark.parametrize` and clean up the naming.
* Skip some tests `#if defined(THREAD_SANITIZER)` (tested with TSAN using the Google-internal toolchain).
* Run all tests again but ignore ThreadSanitizer exitcode 66 (this is less likely to mask unrelated ThreadSanitizer issues in the future).
* bug fix: missing common.h include before using `PYBIND11_SIMPLE_GIL_MANAGEMENT`
For the tests in the github CI this does not matter, because
`PYBIND11_SIMPLE_GIL_MANAGEMENT` is always defined from the command line,
but when monkey-patching common.h locally, it matters.
* if process.exitcode is None: assert t_delta > 9.9
* More sophisiticated `_run_in_process()` implementation, clearly reporting `DEADLOCK`, additionally exercised via added `intentional_deadlock()`
* Wrap m.intentional_deadlock in a Python function, for `ForkingPickler` compatibility.
```
> ForkingPickler(file, protocol).dump(obj)
E TypeError: cannot pickle 'PyCapsule' object
```
Observed with all Windows builds including mingw but not PyPy, and macos-latest with Python 3.9, 3.10, 3.11 but not 3.6.
* Add link to potential solution for WOULD-BE-NICE-TO-HAVE feature.
* Add `SKIP_IF_DEADLOCK = True` option, to not pollute the CI results with expected `DEADLOCK` failures while we figure out what to do about them.
* Add COPY-PASTE-THIS: gdb ... command (to be used for debugging the detected deadlock)
* style: pre-commit fixes
* Do better than automatic pre-commit fixes.
* Add `PYBIND11_SIMPLE_GIL_MANAGEMENT` to `pytest_report_header()` (so that we can easily know when harvesting deadlock information from the CI logs).
Co-authored-by: Arnim Balzer <arnim@seechange.ai>
Co-authored-by: Henry Schreiner <HenrySchreinerIII@gmail.com>
Co-authored-by: Ralf W. Grosse-Kunstleve <rwgk@google.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
* (bugfix): Improve bytes to str decoding error handling
* regroup test
* Further broaden tests
* Add another decode error test
* Fix bug in tests
* Reviewer suggestions
* First draft of Eigen::Tensor support
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* Fix build errors
* Weird allocator stuff?
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Remove unused + additional allocator junk
* Disable warning
* Use constexpr
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* clang tidy fixes
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Resolve comments
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Remove auto constexpr function
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Try again for older C++
* Oops forgot constexpr
* Move to new files as suggested
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Fix weird tests
* Fix nits
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Oops, forgot import
* Fix clang 3.6 bug
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* More comprehensive test suite
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Refactor allocators to make things more clear
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Switch to std::copy
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Switch to DSizes instead of array
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Address feedback
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Fix python + dummy c++ change to trigger build
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Alignment
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Add include guard
* Forgot inline
* Fix compiler warning
* Remove bad test
* Better type signatures
* Add guards to make compiler requirements more explicit
* style: pre-commit fixes
* Force rerun of tests due to flake
* style: pre-commit fixes
* Keep pragmas & all related comments together, add PLEASE KEEP IN SYNC
* Move headers out of detail
* style: pre-commit fixes
* Fix cmake
* Improve casting
* style: pre-commit fixes
* Add a ton more tests + refactor
* Improve names
* style: pre-commit fixes
* Update include/pybind11/eigen/tensor.h
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
* Fix tests
* style: pre-commit fixes
* Update
* Add a test to verify that strange numpy arrays work
* Fix dumb compiler warning
* Better tests
* Better tests
* Fix tests
* style: pre-commit fixes
* More test fixes
* style: pre-commit fixes
* A ton more test coverage
* Fix tests
* style: pre-commit fixes
* style: pre-commit fixes
* Add back constexpr
* Another test
* style: pre-commit fixes
* Improve tests
* Whoops
* Less magic numbers
* Update tests/test_eigen_tensor.py
Co-authored-by: Sergiu Deitsch <sergiud@users.noreply.github.com>
* Update tests/test_eigen_tensor.py
Co-authored-by: Sergiu Deitsch <sergiud@users.noreply.github.com>
* style: pre-commit fixes
* Fix tests
* style: pre-commit fixes
* Fix memory leak
* style: pre-commit fixes
* Fix order
* style: pre-commit fixes
* Add test to make sure unsafe casts fail
* Minor bug fix to work on 32 bit machines
* Implement convert flag
* style: pre-commit fixes
* Switch to correct TensorMap const use
* style: pre-commit fixes
* Support older versions of eigen
* Weird c++ compilers
* Fix Eigen bug
* Fix another eigen bug
* Yet another eigen bug
* Potential flakes?
* style: pre-commit fixes
* Rerun tests with dummy exception to find out what is going on
* Another dummy test run
* Ablate more
* Found the broken test?
* One step closer
* one step further
* Double check
* one thing at a time
* Give up and disable the test
* Clang lies about being gcc
* Oops, fix matrix test
* style: pre-commit fixes
* Add tests to verify scalar conversions
* style: pre-commit fixes
* Fix nits
* Support no_array
* Fix tests
* style: pre-commit fixes
* Silence compiler warning
* Improve build system for ancient compilers
* Make clang happy
* Make gcc happy
* Implement Skylion's suggestions
* Fix warning
* Inline const pointer check
* Implement suggestions
* style: pre-commit fixes
* Improve tests
* Typo
* style: pre-commit fixes
* Support Google's build environment
* style: pre-commit fixes
* Update include/pybind11/eigen/tensor.h
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
* style: pre-commit fixes
* Test cleanup per Skylion
* Switch to remvove_cv_t
* Cleaner test
* style: pre-commit fixes
* Remove tensor from eigen.h, update tests
* style: pre-commit fixes
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Ralf W. Grosse-Kunstleve <rwgk@google.com>
Co-authored-by: Aaron Gokaslan <aaronGokaslan@gmail.com>
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
Co-authored-by: Sergiu Deitsch <sergiud@users.noreply.github.com>
* bugfix: contains now throws an exception if the key is not hashable
* Fix tests and improve robustness
* Remove todo
* Workaround PyPy corner case
* PyPy xfail
* Fix typo
* fix xfail
* Make clang-tidy happy
* Remove redundant exc checking
* Reproducer for issue encountered in smart_holder update.
* clang-tidy compatibility (untested).
* Add `enable_if_t` to workaround.
* Bug fix: Move `PYBIND11_USING_WORKAROUND_FOR_CUDA_11_4_THROUGH_8` determination to detail/common.h
So that it actually is defined in pybind11.h
* Try using the workaround (which is nicer than the original code) universally.
* Reduce reproducer for CUDA 11.7 issue encountered in smart_holder update.
This commit tested in isolation on top of current master + first version of reproducer (62311eb431).
Succeeds with Debian Clang 14.0.6 C++17 (and probably all other compilers).
Fails for CUDA 11.7:
```
cd /build/tests && /usr/local/cuda/bin/nvcc -forward-unknown-to-host-compiler -Dpybind11_tests_EXPORTS -I/mounted_pybind11/include -isystem=/usr/include/python3.10 -g --generate-code=arch=compute_52,code=[compute_52,sm_52] -Xcompiler=-fPIC -Xcompiler=-fvisibility=hidden -Werror all-warnings -std=c++17 -MD -MT tests/CMakeFiles/pybind11_tests.dir/test_class.cpp.o -MF CMakeFiles/pybind11_tests.dir/test_class.cpp.o.d -x cu -c /mounted_pybind11/tests/test_class.cpp -o CMakeFiles/pybind11_tests.dir/test_class.cpp.o
/mounted_pybind11/tests/test_class.cpp(53): error: more than one instance of overloaded function "pybind11::class_<type_, options...>::def [with type_=test_class::pr4220_tripped_over_this::Empty0, options=<>]" matches the argument list:
function template "pybind11::class_<test_class::pr4220_tripped_over_this::Empty0> &pybind11::class_<type_, options...>::def(const char *, Func &&, const Extra &...) [with type_=test_class::pr4220_tripped_over_this::Empty0, options=<>]"
/mounted_pybind11/include/pybind11/pybind11.h(1557): here
function template "pybind11::class_<test_class::pr4220_tripped_over_this::Empty0> &pybind11::class_<type_, options...>::def(const T &, const Extra &...) [with type_=test_class::pr4220_tripped_over_this::Empty0, options=<>]"
/mounted_pybind11/include/pybind11/pybind11.h(1586): here
argument types are: (const char [8], <unknown-type>)
object type is: pybind11::class_<test_class::pr4220_tripped_over_this::Empty0>
1 error detected in the compilation of "/mounted_pybind11/tests/test_class.cpp".
```
* fix: PyCapsule_GetDestructor is allowed to return a nullptr destructor
Previously, this code would error out if the destructor happened to be
a nullptr. This is incorrect. nullptrs are allowed for capsule
destructors.
"It is legal for a capsule to have a NULL destructor. This makes a
NULL return code somewhat ambiguous; use PyCapsule_IsValid() or
PyErr_Occurred() to disambiguate."
See:
https://docs.python.org/3/c-api/capsule.html#c.PyCapsule_GetDestructor
I noticed this while working on a type caster related to #3858 DLPack
happens to allow the destructor not to be defined on a capsule, and I
encountered such a case. See:
e2bdd3bee8/include/dlpack/dlpack.h (L219)
* Add test for the fix.
* Update tests/test_pytypes.cpp
I tried this locally and it works!
I never knew that there are cases where `reinterpret_cast` does not work but `static_cast` does. Let's see if all compilers are happy with this.
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
* style: pre-commit fixes
Co-authored-by: Ralf W. Grosse-Kunstleve <rwgk@google.com>
Co-authored-by: Ralf W. Grosse-Kunstleve <rwgkio@gmail.com>
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
* Disable test triggering ASAN failure (to pin-point where the problem is).
* Fix unsafe "block" implementation in test_eigen.cpp
* Undo changes (i.e. revert back to master).
* Detect "type_caster for Eigen::Ref made a copy."
This is achieved without
* reaching into internals,
* making test_eigen.cpp depend on pybind11/numpy.h.
* Add comment pointing to PR, for easy reference.
* Add debug fprintf to test_interpreter.cpp
* Update `sys.path` from `PYTHONPATH` in Python >= 3.11 branch of `initialize_interpreter()`
* Use `config.isolated = 0; config.use_environment = 1;`
As suggsted by @vstinner here: https://github.com/pybind/pybind11/pull/4119#issuecomment-1219442853
* Add `TEST_CASE("PYTHONPATH is used to update sys.path")`
* Fix clang-tidy error.
* Use `_putenv_s()` under Windows.
* Fix clang-tidy error: argument name ... in comment does not match parameter name
* Remove slash from PYTHONPATH addition, to work around Windows slash-vs-backslash issue.
* Use `py::str(...)` instead of `.attr("__str__")` as suggested by @skylion007
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
* add installation support for pkg-config dependency detection
pkg-config is a buildsystem-agnostic alternative to
`pybind11Config.cmake` that can be used from build systems other than
cmake.
Fixes#230
* tests: add test for pkg config
Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>
* Add `-DPYBIND11_WERROR=ON` to mingw cmake commands (and `-DCMAKE_VERBOSE_MAKEFILE:BOOL=ON`).
* Using no-destructor idiom to side-step overzealous MINGW warning.
* Add __MINGW32__ pragma GCC diagnostic ignored in eigen.h
* Add another no-destructor workaround.
* Temporarily add -k (keep-going) flags to hopefully speed up finding all warnings.
* Revert "Temporarily add -k (keep-going) flags to hopefully speed up finding all warnings."
This reverts commit f36b0af8f9.
* Very minor shuffle to avoid MSVC warnings.
* Remove all `:BOOL` as suggested by @henryiii
* For PyPy only, re-enable old behavior (likely to mask bugs), to avoid segfault with unknown root cause.
Change prompted by https://github.com/pybind/pybind11/issues/4075
* Undo the change in tests/test_exceptions.py
I turns out (I forgot) that PyPy segfaults in `test_flaky_exception_failure_point_init` already before the `MISMATCH` code path is reached:
https://github.com/pybind/pybind11/runs/7383663596
```
RPython traceback:
test_exceptions.py .......X.........Error in cpyext, CPython compatibility layer:
File "pypy_module_cpyext.c", line 14052, in wrapper_second_level__star_3_1
File "pypy_module_cpyext_1.c", line 35750, in not_supposed_to_fail
Fatal Python error: Segmentation fault
Stack (most recent call first, approximate line numbers):
File "/home/runner/work/pybind11/pybind11/tests/test_exceptions.py", line 306 in test_flaky_exception_failure_point_init
The function PyErr_NormalizeException was not supposed to fail
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/python.py", line 185 in pytest_pyfunc_call
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_callers.py", line 9 in _multicall
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_manager.py", line 77 in _hookexec
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_hooks.py", line 244 in __call__
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/python.py", line 1716 in runtest
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/runner.py", line 159 in pytest_runtest_call
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_callers.py", line 9 in _multicall
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_manager.py", line 77 in _hookexec
Fatal error in cpyext, CPython compatibility layer, calling PyErr_NormalizeException
Either report a bug or consider not using this particular extension
<SystemError object at 0x7fcc8cea6868>
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_hooks.py", line 244 in __call__
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/runner.py", line 261 in <lambda>
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/runner.py", line 317 in from_call
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/runner.py", line 246 in call_runtest_hook
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/runner.py", line 218 in call_and_report
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/runner.py", line 118 in runtestprotocol
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/runner.py", line 110 in pytest_runtest_protocol
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_callers.py", line 9 in _multicall
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_manager.py", line 77 in _hookexec
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_hooks.py", line 244 in __call__
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/main.py", line 335 in pytest_runtestloop
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_callers.py", line 9 in _multicall
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_manager.py", line 77 in _hookexec
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_hooks.py", line 244 in __call__
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/main.py", line 318 in _main
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/main.py", line 255 in wrap_session
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/main.py", line 314 in pytest_cmdline_main
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_callers.py", line 9 in _multicall
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_manager.py", line 77 in _hookexec
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pluggy/_hooks.py", line 244 in __call__
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/config/__init__.py", line 133 in main
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/_pytest/config/__init__.py", line 181 in console_main
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/site-packages/pytest/__main__.py", line 1 in <module>
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/lib-python/3/runpy.py", line 62 in _run_code
File "/opt/hostedtoolcache/PyPy/3.7.13/x64/lib-python/3/runpy.py", line 170 in _run_module_as_main
File "<builtin>/app_main.py", line 109 in run_toplevel
File "<builtin>/app_main.py", line 652 in run_command_line
File "<builtin>/app_main.py", line 996 in entry_point
Segmentation fault (core dumped)
```
* Add test_pypy_oserror_normalization
* Disable new `PYPY_VERSION` `#if`, to verify that the new test actually fails.
* Restore PYPY_VERSION workaround and update comment to reflect what was learned.
* [ci skip] Fix trivial oversight in comment.
* Disable implicit conversion from `0` to `pybind11::handle`.
* Reverse or-ed condition in an attempt to resolve GCC 8.3.0 errors (i386/debian:buster).
* Trying the simpler `std::is_same<T, PyObject *>`
* Add implicit_conversion_from_pytorch_THPObjectPtr_to_handle test.
* Accommodate types with implicit conversions to `PyObject *`, other than `handle` & `handle` subclasses, or integral types.
* Fix copy-paste mishap (picked wrong name).
* Revamp SFINAE construct to actually fix the pytorch issue (already validated against pytorch proper).
The first version of the reduced pytorch code was critically missing the move ctor. The first version of the accompanying test was meaningless.
Note: It turns out the `!std::is_arithmetic<T>` condition is not needed: `int` is not in general implicitly convertible to `PyObject *`, only the literal `0` is.
* Use `NOLINT(performance-noexcept-move-constructor)` for reduced code from the wild (rather than changing the code).
* Use any_of, all_of, negation. It turns out to clang-format nicer.
* Clean up comments for changed code.
* Reduce pytorch situation further, add test for operator ... const.
* Use `none_of` as suggested by @skylion007
* Add `pure_compile_tests_for_handle_from_PyObject_pointers()`
* Fix inconsequential oversight (retested).
* Factor our `is_pyobj_ptr_or_nullptr_t` to make the SFINAE conditions more readable.
* Remove stray line (oversight).
* Make the `pure_compile_tests_for_handle_from_PyObject_pointers()` "rhs-const-complete", too.
* Remove the temporary PYBIND11_UNDO_PR4008 `#ifdef`.
