GitLab

* Disambiguate free() to use std::free()

* Add cstdlib include

* Add `.keys` and `.values` to bind_map

Both of these implement views (rather than just iterators), and `.items`
is also upgraded to a view. In practical terms, this allows a view to be
iterated multiple times and have its size taken, neither of which works
with an iterator.

The views implement `__len__`, `__iter__`, and the keys view implements
`__contains__`. Testing membership also works in item and value views
because Python falls back to iteration. This won't be optimal
for item values since it's linear rather than O(log n) or O(1), but I
didn't fancy trying to get all the corner cases to match Python
behaviour (tuple of wrong types, wrong length tuple, not a tuple etc).

Missing relative to Python dictionary views is `__reversed__` (only
added to Python in 3.8). Implementing that could break code that binds
custom map classes which don't provide `rbegin`/`rend` (at least without
doing clever things with SFINAE), so I've not tried.

The size increase on my system is 131072 bytes, which is rather large
(5%) but also suspiciously round (2^17) and makes me suspect some
quantisation effect.

* bind_map: support any object in __contains__

Add extra overload of `__contains__` (for both the map itself and
KeysView) which takes an arbitrary object and returns false.

* Take py::object by const reference in __contains__

To keep clang-tidy happy.

* Removing stray `py::` (detected via interactive testing in Google environment).
Co-authored-by: Ralf W. Grosse-Kunstleve <rwgk@google.com>

* Fix `pybind11::object::operator=` to be safe if `*this` is accessible from Python

* Add `custom_type_setup` attribute

This allows for custom modifications to the PyHeapTypeObject prior to
calling `PyType_Ready`.  This may be used, for example, to define
`tp_traverse` and `tp_clear` functions.

* Add make_value_iterator (#3271)

* Add make_value_iterator

This is the counterpart to make_key_iterator, and will allow
implementing a `value` method in `bind_map` (although doing so is left
for a subsequent PR).

I made a few design changes to reduce copy-and-paste boilerplate.
Previously detail::iterator_state had a boolean template parameter to
indicate whether it was being used for make_iterator or
make_key_iterator. I replaced the boolean with a class that determines
how to dereference the iterator. This allows for a generic
implementation of `__next__`.

I also added the ValueType and Extra... parameters to the iterator_state
template args, because I think it was a bug that they were missing: if
make_iterator is called twice with different values of these, only the
first set has effect (because the state class is only registered once).
There is still a potential issue in that the *values* of the extra
arguments are latched on the first call, but since most policies are
empty classes this should be even less common.

* Add some remove_cv_t to appease clang-tidy

* Make iterator_access and friends take reference

For some reason I'd accidentally made it take a const value, which
caused some issues with third-party packages.

* Another attempt to remove remove_cv_t from iterators

Some of the return types were const (non-reference) types because of the
pecularities of decltype: `decltype((*it).first)` is the *declared* type
of the member of the pair, rather than the type of the expression. So if
the reference type of the iterator is `pair<const int, int> &`, then the
decltype is `const int`. Wrapping an extra set of parentheses to form
`decltype(((*it).first))` would instead give `const int &`.

This means that the existing make_key_iterator actually returns by value
from `__next__`, rather than by reference. Since for mapping types, keys
are always const, this probably hasn't been noticed, but it will affect
make_value_iterator if the Python code tries to mutate the returned
objects. I've changed things to use double parentheses so that
make_iterator, make_key_iterator and make_value_iterator should now all
return the reference type of the iterator. I'll still need to add a test
for that; for now I'm just checking whether I can keep Clang-Tidy happy.

* Add back some NOLINTNEXTLINE to appease Clang-Tidy

This is favoured over using remove_cv_t because in some cases a const
value return type is deliberate (particularly for Eigen).

* Add a unit test for iterator referencing

Ensure that make_iterator, make_key_iterator and make_value_iterator
return references to the container elements, rather than copies. The
test for make_key_iterator fails to compile on master, which gives me
confidence that this branch has fixed it.

* Make the iterator_access etc operator() const

I'm actually a little surprised it compiled at all given that the
operator() is called on a temporary, but I don't claim to fully
understand all the different value types in C++11.

* Attempt to work around compiler bugs

https://godbolt.org/

 shows an example where ICC gets the wrong result
for a decltype used as the default for a template argument, and CI also
showed problems with PGI. This is a shot in the dark to see if it fixes
things.

* Make a test constructor explicit (Clang-Tidy)

* Fix unit test on GCC 4.8.5

It seems to require the arguments to the std::pair constructor to be
implicitly convertible to the types in the pair, rather than just
requiring is_constructible.

* Remove DOXYGEN_SHOULD_SKIP_THIS guards

Now that a complex decltype expression has been replaced by a simpler
nested type, I'm hoping Doxygen will be able to build it without issues.

* Add comment to explain iterator_state template params

* fix: regression in #3271
Co-authored-by: Bruce Merry <1963944+bmerry@users.noreply.github.com>

This reverts commit ee0c5ee4.

* Adding nullptr slices

Using example from #1095

Some fixes from @wjakob's review

Stop clang-tidy from complaining

New proposal for py::slice constructor

Eric's suggested changes: simplify testing; shift def's

* chore: drop MSVC pragma (hopefully unneeded)

* Apply suggestions from code review

* Add make_value_iterator

This is the counterpart to make_key_iterator, and will allow
implementing a `value` method in `bind_map` (although doing so is left
for a subsequent PR).

I made a few design changes to reduce copy-and-paste boilerplate.
Previously detail::iterator_state had a boolean template parameter to
indicate whether it was being used for make_iterator or
make_key_iterator. I replaced the boolean with a class that determines
how to dereference the iterator. This allows for a generic
implementation of `__next__`.

I also added the ValueType and Extra... parameters to the iterator_state
template args, because I think it was a bug that they were missing: if
make_iterator is called twice with different values of these, only the
first set has effect (because the state class is only registered once).
There is still a potential issue in that the *values* of the extra
arguments are latched on the first call, but since most policies are
empty classes this should be even less common.

* Add some remove_cv_t to appease clang-tidy

* Make iterator_access and friends take reference

For some reason I'd accidentally made it take a const value, which
caused some issues with third-party packages.

* Another attempt to remove remove_cv_t from iterators

Some of the return types were const (non-reference) types because of the
pecularities of decltype: `decltype((*it).first)` is the *declared* type
of the member of the pair, rather than the type of the expression. So if
the reference type of the iterator is `pair<const int, int> &`, then the
decltype is `const int`. Wrapping an extra set of parentheses to form
`decltype(((*it).first))` would instead give `const int &`.

This means that the existing make_key_iterator actually returns by value
from `__next__`, rather than by reference. Since for mapping types, keys
are always const, this probably hasn't been noticed, but it will affect
make_value_iterator if the Python code tries to mutate the returned
objects. I've changed things to use double parentheses so that
make_iterator, make_key_iterator and make_value_iterator should now all
return the reference type of the iterator. I'll still need to add a test
for that; for now I'm just checking whether I can keep Clang-Tidy happy.

* Add back some NOLINTNEXTLINE to appease Clang-Tidy

This is favoured over using remove_cv_t because in some cases a const
value return type is deliberate (particularly for Eigen).

* Add a unit test for iterator referencing

Ensure that make_iterator, make_key_iterator and make_value_iterator
return references to the container elements, rather than copies. The
test for make_key_iterator fails to compile on master, which gives me
confidence that this branch has fixed it.

* Make the iterator_access etc operator() const

I'm actually a little surprised it compiled at all given that the
operator() is called on a temporary, but I don't claim to fully
understand all the different value types in C++11.

* Attempt to work around compiler bugs

https://godbolt.org/ shows an example where ICC gets the wrong result
for a decltype used as the default for a template argument, and CI also
showed problems with PGI. This is a shot in the dark to see if it fixes
things.

* Make a test constructor explicit (Clang-Tidy)

* Fix unit test on GCC 4.8.5

It seems to require the arguments to the std::pair constructor to be
implicitly convertible to the types in the pair, rather than just
requiring is_constructible.

* Remove DOXYGEN_SHOULD_SKIP_THIS guards

Now that a complex decltype expression has been replaced by a simpler
nested type, I'm hoping Doxygen will be able to build it without issues.

* Add comment to explain iterator_state template params

* Enable defining custom __new__

* See if xfail needed

* Qualify auto self

* Unconditionally defining PYBIND11_DISABLE_NEW_STYLE_INIT_WARNING. Returning pointer from "__init__" instead of reference.

* Use new style __init__

* Simplify __new__ creation

* Reviewer suggestions

* Match indentation
Co-authored-by: Ralf W. Grosse-Kunstleve <rwgk@google.com>

* Eliminate duplicate TLS keys for loader_life_support stack

This revises the existing fix for
https://github.com/pybind/pybind11/issues/2765 in
https://github.com/pybind/pybind11/pull/3237 to reduce the amount of
TLS storage used.

The shared TLS key is stored in two different ways, depending on
`PYBIND11_INTERNALS_VERSION`.  If `PYBIND11_INTERNALS_VERSION ==
4` (as is currently set), the TLS key is stored in the
`internal::shared_data` map to avoid breaking ABI compatibility.  If
`PYBIND11_INTERNALS_VERSION > 4`, the TLS key is stored directly in
the `internals` struct.

* Fix test_pytypes.py::test_issue2361 failure on PyPy3.7

* Add github actions tests for unstable ABI

* Restoring `const` removed from pytypes.h in PR #3254, adding tests reflective of user code that breaks when those `const` are removed.

* clang-tidy NOLINTs (and one collateral fix).

* Inserting PYBIND11_CONST_FOR_STRICT_PLATFORMS

* Trying `defined(__APPLE__)`

* Trying again: `auto it` for strict platforms.

* Adding NOLINTNEXTLINE(bugprone-macro-parentheses), expanding comments.

* Labeling all changes with `PR #3263`, for easy reference, and to make it easy to undo these changes if we decide to do so in the future.

Thanks Aaron for jumping in fixing this!

* Fix thread safety for pybind11 loader_life_support

Fixes issue: https://github.com/pybind/pybind11/issues/2765

This converts the vector of PyObjects to either a single void* or
a per-thread void* depending on the WITH_THREAD define.

The new field is used by each thread to construct a stack
of loader_life_support frames that can extend the life of python
objects.

The pointer is updated when the loader_life_support object is allocated
(which happens before a call) as well as on release.

Each loader_life_support maintains a set of PyObject references
that need to be lifetime extended; this is done by storing them
in a c++ std::unordered_set and clearing the references when the
method completes.

* Also update the internals version as the internal struct is no longer compatible

* Add test demonstrating threading works correctly.

It may be appropriate to run this under msan/tsan/etc.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Update test to use lifetime-extended references rather than
std::string_view, as that's a C++ 17 feature.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Make loader_life_support members private

* Update version to dev2

* Update test to use python threading rather than concurrent.futures

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Remove unnecessary env in test

* Remove unnecessary pytest in test

* Use native C++ thread_local in place of python per-thread data structures to retain compatability

* clang-format test_thread.cpp

* Add a note about debugging the py::cast() error

* thread_test.py now propagates exceptions on join() calls.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* remove unused sys / merge

* Update include order in test_thread.cpp

* Remove spurious whitespace

* Update comment / whitespace.

* Address review comments

* lint cleanup

* Fix test IntStruct constructor.

* Add explicit to constructor
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>

* Removing NOLINT pointed out by Aaron.

* Removing another NOLINT.

* Enable clang-tidy readability-const-return

* PyTest functional

* Fix regression

* Fix actual regression

* Remove one more NOLINT

* Update comment

Fixes #3252

* Set __file__ constant when using eval_file

* Use const ref

* Use a move instead

* Revert

* Improve test

* Guard test with Python version

* Fix tests

* Dont support Python2 API

* Drop Python2 eval __file__ support

* Hack

* Semisupport Python2

* Take2

* Remove Python2 support

* Adding google-explicit-constructor to .clang-tidy

* clang-tidy explicit attr.h (all automatic)

* clang-tidy explicit cast.h (all automatic)

* clang-tidy detail/init.h (1 NOLINT)

* clang-tidy detail/type_caster_base.h (2 NOLINT)

* clang-tidy pybind11.h (7 NOLINT)

* clang-tidy detail/common.h (3 NOLINT)

* clang-tidy detail/descr.h (2 NOLINT)

* clang-tidy pytypes.h (23 NOLINT, only 1 explicit)

* clang-tidy eigen.h (7 NOLINT, 0 explicit)

* Adding 2 explicit in functional.h

* Adding 4 explicit in iostream.h

* clang-tidy numpy.h (1 NOLINT, 1 explicit)

* clang-tidy embed.h (0 NOLINT, 1 explicit)

* clang-tidy tests/local_bindings.h (0 NOLINT, 4 explicit)

* clang-tidy tests/pybind11_cross_module_tests.cpp (0 NOLINT, 1 explicit)

* clang-tidy tests/pybind11_tests.h (0 NOLINT, 2 explicit)

* clang-tidy tests/test_buffers.cpp (0 NOLINT, 2 explicit)

* clang-tidy tests/test_builtin_casters.cpp (0 NOLINT, 4 explicit)

* clang-tidy tests/test_class.cpp (0 NOLINT, 6 explicit)

* clang-tidy tests/test_copy_move.cpp (0 NOLINT, 7 explicit)

* clang-tidy tests/test_embed/external_module.cpp (0 NOLINT, 1 explicit)

* clang-tidy tests/test_embed/test_interpreter.cpp (0 NOLINT, 1 explicit)

* clang-tidy tests/object.h (0 NOLINT, 2 explicit)

* clang-tidy batch of fully automatic fixes.

* Workaround for MSVC 19.16.27045.0 C++17 Python 2 C++ syntax error.

* Add a missing noexcept to pytypes constructor.

Adds a few missing noexcept to PyType constructors for perf reasons.

* Revert exception ctor

* fix: memory leak in cpp_function (#3228)

* add a test case to check objects are deconstructed in cpp_function

* update the test case about cpp_function

* fix the test case about cpp_function: remove "noexcept"

* Actually calling func. CHECK(stat.alive() == 2); Manually verified that the new tests fails without the change in pybind11.h

* Moving new test to test_callbacks.cpp,py, with small enhancements.

* Removing new test from test_interpreter.cpp (after it was moved to test_callbacks.cpp,py). This restores test_interpreter.cpp to the current state on master.

* Using py::detail::silence_unused_warnings(py_func); to make the intent clear.
Co-authored-by: Ralf W. Grosse-Kunstleve <rwgk@google.com>

Adding `ssize_t_cast` to support passing `size_t` or `ssize_t` values where `ssize_t` is needed. (#3219)

* Trivial change to avoid (ssize_t) cast.

* Demo for safe_ssize_t idea.

* Removing safe_ssize_t.cpp (proof-of-concept code) to not upset the GHA Format workflow.

* Completing changes in pytypes.h

* New ssize_t_cast (better replacement for safe_ssize_t).

* clang-format-diff (no manual changes).

* bytes_ssize_t -Wnarrowing reproducer (see PR #2692).

* Backing out tuple(), list() ssize_t support, for compatibility with older compilers (to resolve link failures).

* Bug fix: missing `py::` for `py::ssize_t`

* Restoring tuple(), list() ssize_t support, but passing `size` by value, for compatibility with older compilers (to resolve link failures).

* Full test coverage of all functions with modified signatures.

* Use equivalent_integer for enum's Scalar decision

* Add test for char underlying enum

* Support translating bool type in enum's Scalar

* Add test for bool underlying enum

* Fix comment in test

* Switch from `PYBIND11_CPP20` macro to `PYBIND11_HAS_U8STRING`

* Refine tests
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>

* Call PySys_SetArgv when initializing interpreter.

* Document argc/argv parameters in initialize_interpreter.

* Remove manual memory management from set_interpreter_argv in favor of smart pointers.

* Use size_t for indexers in set_interpreter_argv.

* Minimize macros for flow control in set_interpreter_argv.

* Fix 'unused variable' warning on Py2

* whitespace

* Define wide_char_arg_deleter outside set_interpreter_argv.

* Do sys.path workaround in C++ rather than eval.

* Factor out wchar conversion to a separate function.

* Restore widened_argv variable declaration.

* Fix undeclared widened_arg variable on some paths.

* Use delete[] to match new wchar_t[].

* Fix compiler errors

* Use PY_VERSION_HEX for a cleaner CVE-2008-5983 mode check.

* Fix typo

* Use explicit type for deleter so delete[] works cross-compiler.

* Always use PySys_SetArgvEx because pybind11 doesn't support pythons that don't include it.

* Remove pointless ternary operator.

* Use unique_ptr.reset instead of a second initialization.

* Rename add_program_dir_to_path parameter to clarify intent.

* Add defined() check before evaluating HAVE_BROKEN_MBSTOWCS.

* Apply clang-tidy fixes

* Pre-commit

* refactor: use const for set_interpreter_argv

* Try to fix const issue and allocate vector properly

* fix: copy strings on Python 2

* Applying clang-format-diff relative to master.

The only manual change is an added empty line between pybind11 and system `#include`s.

```
git diff -U0 --no-color master | python3 $HOME/clone/llvm-project/clang/tools/clang-format/clang-format-diff.py -p1 -style=file -i
```
Co-authored-by: Boris Staletic <boris.staletic@gmail.com>
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: Ralf W. Grosse-Kunstleve <rwgk@google.com>

* reshape

* more tests

* Update numpy.h

* Update test_numpy_array.py

* array view

* test

* Update test_numpy_array.cpp

* Update numpy.h

* Update numpy.h

* Update test_numpy_array.cpp

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci



* Fix merge bug

* Make clang-tidy happy

* Add xfail for PyPy

* Fix casting issue

* Fix formatting

* Apply clang-tidy

* Address reviews on additional tests

* Fix ordering

* Do a little more reordering

* Fix typo

* Try improving tests

* Fix error in reshape

* Add one more reshape test

* Fix bugs and add test

* Relax test

* streamlining new tests; removing a few stray msg

* Fix style revert

* Fix clang-tidy

* Misc tweaks:
* Comment: matching style in file (///), responsibility sentence, consistent punctuation.
* Replacing `unsigned char` with `uint8_t` for max consistency.
* Removing `1` from `array_view1` because there is only one.

* Partial clang-format-diff.
Co-authored-by: ncullen93 <ncullen.th@dartmouth.edu>
Co-authored-by: NC Cullen <nicholas.c.cullen.th@dartmouth.edu>
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>
Co-authored-by: Ralf Grosse-Kunstleve <rwgk@google.com>

* reshape

* more tests

* Update numpy.h

* Update test_numpy_array.py

* Update numpy.h

* Update numpy.h

* Update test_numpy_array.cpp

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* Fix merge bug

* Make clang-tidy happy

* Add xfail for PyPy

* Fix casting issue

* Address reviews on additional tests

* Fix ordering

* Do a little more reordering

* Fix typo

* Try improving tests

* Fix error in reshape

* Add one more reshape test

* streamlining new tests; removing a few stray msg
Co-authored-by: ncullen93 <ncullen.th@dartmouth.edu>
Co-authored-by: NC Cullen <nicholas.c.cullen.th@dartmouth.edu>
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>
Co-authored-by: Ralf Grosse-Kunstleve <rwgk@google.com>

Co-authored-by: Jouke Witteveen <j.witteveen@cosine.nl>

* Add py::raise_from to enable chaining exceptions on Python 3.3+

* Use 'raise from' in initialization

* Documenting the exact base version of _PyErr_FormatVFromCause, adding back `assert`s.
Co-authored-by: Dustin Spicuzza <dustin@virtualroadside.com>

* maint(clang-tidy): add a clang-tidy slicing check

* Add self + touch up readme

* Fix typo

Cleanup of file-scoped and globally-scoped warning suppression pragmas across pybind11 header files. (#3201)

* Removing all MSVC C4127 warning suppression pragmas.

* Removing MSVC /WX (WERROR). To get a full list of all warnings.

* Inserting PYBIND11_SILENCE_MSVC_C4127. Changing one runtime if to #if.

* Changing PYBIND11_SILENCE_MSVC_C4127 macro to use absolute namespace (for use outside pybind11 include directory).

* Restoring MSVC /WX (WERROR).

* Removing globally-scoped suppression for clang -Wunsequenced. Based on an experiment under PR #3202 it is obsolete and can simply be removed.

* Removing all pragma from eigen.h

* Removing -Werror or equivalent from tests/CMakeLists.txt

* Restoring tests/CMakeLists.txt from master.

* Adding 4 PYBIND11_SILENCE_MSVC_C4127.

* Compatibility with -Wconversion, -Wdeprecated

* Introducing PYBIND11_COMPATIBILITY_WDEPRECATED_COPY

* Systematically using --verbose for compilations where possible (cmake 3.14 or newer).

Also changing all `cmake -t` to `--target`, `-v` to `--verbose`, `check` to `pytest`, for consistency (to make it easier to pin-point all commands of a certain type).

Also removing one `-j 2` for `pytest` in hopes of reducing flakes due to races in test_iostream and in prints from destructors.

* Commenting out pragmas as an experiment to reproduce previous observation.

* Removing all (newly added, but already commented-out) pragma code, adding HINT use -isystem (as cmake does).

* Restoring ci.yml from master. Those changes are better handled separately. BTW: in the last CI run there was still a test_iostream flake, even without the -j 2 for running the tests (verfied by inspecting the log).

* Fix errant const methods

* Remove NOLINT since clang-tidy is pretty conservative

* Missed one

* Fix a few more errors

* Add reviewer suggested comments

* Run clang-format

* Removing last remnants of pragma block at the top of pybind11.h, defaulting CUDA, GCC7, GCC8 to PYBIND11_NOINLINE_DISABLED, with the option to define PYBIND11_NOINLINE_FORCED.

* Unique SOSIZE prefix to make it easier to extract the sosizes from the GitHub logs.

* Commenting out PYBIND11_WERROR block, for noinline testing.

* Undoing accidental change.

* `#define PYBIND11_NOINLINE_FORCED`

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* `#define PYBIND11_NOINLINE_DISABLED`

* Going back to default (removing `#define PYBIND11_NOINLINE_DISABLED`).

* `#define PYBIND11_NOINLINE_FORCED`

* Undoing all changes releated to measuring sosizes.

* Rollback of PR #3030 (Working around Centos 8 failure).

* Disabling -Werror for GNU (experiment).

* Commenting out the entire `if(PYBIND11_WERROR)` again (although that is not expected to make a difference, but who knows what I am overlooking).

* Adding `-DCMAKE_BUILD_TYPE=Release`

* Undoing change to tests/CMakeLists.txt (uncommenting `if(PYBIND11_WERROR)` block).

* post `git rebase master -X theirs` fixups.

* Adding measurements to comment for `PYBIND11_NOINLINE_FORCED`.
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

* Removing pragma for GCC -Wattributes, fixing forward declarations.

* Introducing PYBIND11_NOINLINE_FWD to deal with CUDA, GCC7, GCC8.

* Updating PYBIND11_NOINLINE_DCL in Doxyfile.

* Trying noinline, noinline for {CUDA, GCC7, GCC8}

* Trying noinline, inline for {CUDA, GCC7, GCC8}

* Adding GCC -Wattributes `pragma` in 3 header files.

* Introducing PYBIND11_NOINLINE_GCC_PRAGMA_ATTRIBUTES_NEEDED, used in 9 header files.

* Removing ICC pragma 2196, to see if it is still needed.

* Trying noinline, noinline for ICC

* Trying noinline, inline for ICC

* Restoring ICC pragma 2196, introducing PYBIND11_NOINLINE_FORCED, defined for testing.

* Removing code accidentally left in (was for experimentation only).

* Removing one-time-test define.

* Removing PYBIND11_NOINLINE_FWD macro (after learning that it makes no sense).

* Testing with PYBIND11_NOINLINE_DISABLED. Minor non-functional enhancements.

* Removing #define PYBIND11_NOINLINE_DISABLED (test was successful).

* Removing PYBIND11_NOINLINE_FORCED and enhancing comments for PYBIND11_NOINLINE.

* WIP stripping back

* Making -Wattributes pragma in pybind11 specific to GCC7, GCC8, CUDA.

* maint(perf): Optimize Numpy Constructor with additional std::move

* Add more moves

* Cleanup triggered by work on pragma for GCC -Wunused-but-set-parameter.

* Backing out changes to eigen.h (to be worked on later).

* Adding PYBIND11_WORKAROUND_INCORRECT_GCC_UNUSED_BUT_SET_PARAMETER in type_caster_base.h (apparently needed only for older GCCs).

* Apparently older compilers need a simpler overload for silence_unused_warnings().

* clang C++11 compatibility: removing constexpr

* Special case for MSVC 2017: `constexpr void` return

* Trying again without the silence_unused_warnings(const int *) overload.

* Separate macros for ALL_GCC, OLD_GCC_UNUSED_BUT_SET_PARAMETER

* Changing to __GNUC__ <= 2 (turning off)

* Refined condition for PYBIND11_WORKAROUND_INCORRECT_OLD_GCC_UNUSED_BUT_SET_PARAMETER.

* Quick experiment trying out suggestion by @henryiii

* Introducing macro: PYBIND11_INT_ARRAY_WORKING_AROUND_MSVC_CLANG_ISSUES

* Trying henryiii@ (void) expander idea.

* fix: apply simpler expression with fewer workarounds

* Purging new-but-already-obsoleted  macro, made possible by @henryiii's commit.

* Renaming `ALL_GCC` macro back to just `GCC` (because there is no `OLD` anymore, luckily).

* [actions skip] Adding "All GCC versions" to comment, to be clear about it.
Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>

* Enable bugprone checks

* Reset delta and massage config

* Start to apply bugprone fixes

* try to fix minor bug

* Fix later

* Fix perfect forwarding bugprone

* Remove nolint

* undo constructor delete

* Fix bugprone-perfect-forwarding again

* Remove TODO

* Add another nolint for bugprone-exception-escape in scoped interpreter

* Fix remaining bugprone errors

* Properly apply bugprone-macro-parantheses

* Redo formatting and remove bugprone nolint

* Add coment and revert more whitespace changes

* Fix typo

* Fix parsing bug

* Add back comma

* Fix clang-tidy issue

* Apply remaining clang-tidy fixes

This reverts commit 1fafd1b4.