Several built-in and standard library types now ensure that their internal result tuples are always tracked by the garbage collector:
- collections.OrderedDict.items
- dict.items
- enumerate
- functools.reduce
- itertools.combinations
- itertools.combinations_with_replacement
- itertools.permutations
- itertools.product
- itertools.zip_longest
- zip
Previously, they could have become untracked by a prior garbage collection.
No longer use deprecated aliases to functions:
* Replace PyObject_MALLOC() with PyObject_Malloc()
* Replace PyObject_REALLOC() with PyObject_Realloc()
* Replace PyObject_FREE() with PyObject_Free()
* Replace PyObject_Del() with PyObject_Free()
* Replace PyObject_DEL() with PyObject_Free()
No longer use deprecated aliases to functions:
* Replace PyMem_MALLOC() with PyMem_Malloc()
* Replace PyMem_REALLOC() with PyMem_Realloc()
* Replace PyMem_FREE() with PyMem_Free()
* Replace PyMem_Del() with PyMem_Free()
* Replace PyMem_DEL() with PyMem_Free()
Modify also the PyMem_DEL() macro to use directly PyMem_Free().
Reduce memory footprint and improve performance of loading modules having many func annotations.
>>> sys.getsizeof({"a":"int","b":"int","return":"int"})
232
>>> sys.getsizeof(("a","int","b","int","return","int"))
88
The tuple is converted into dict on the fly when `func.__annotations__` is accessed first.
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Co-authored-by: Inada Naoki <songofacandy@gmail.com>
Use @staticmethod on methods using @classmethod but don't use their
cls parameter on the following classes:
* BuiltinImporter
* FrozenImporter
* WindowsRegistryFinder
* PathFinder
Leave methods using @_requires_builtin or @_requires_frozen unchanged,
since this decorator requires the wrapped method to have an extra parameter
(cls or self).
Simplify the importlib external bootstrap code:
importlib._bootstrap_external now uses regular imports to import
builtin modules. When it is imported, the builtin __import__()
function is already fully working and so can be used to import
builtin modules like sys.
Convert the _imp extension module to the multi-phase initialization
API (PEP 489).
* Add _PyImport_BootstrapImp() which fix a bootstrap issue: import
the _imp module before importlib is initialized.
* Add create_builtin() sub-function, used by _imp_create_builtin().
* Initialize PyInterpreterState.import_func earlier, in
pycore_init_builtins().
* Remove references to _PyImport_Cleanup(). This function has been
renamed to finalize_modules() and moved to pylifecycle.c.
Remove the undocumented PyOS_InitInterrupts() C function.
* Rename PyOS_InitInterrupts() to _PySignal_Init(). It now installs
other signal handlers, not only SIGINT.
* Rename PyOS_FiniInterrupts() to _PySignal_Fini()
time.time(), time.perf_counter() and time.monotonic() functions can
no longer fail with a Python fatal error, instead raise a regular
Python exception on failure.
Remove _PyTime_Init(): don't check system, monotonic and perf counter
clocks at startup anymore.
On error, _PyTime_GetSystemClock(), _PyTime_GetMonotonicClock() and
_PyTime_GetPerfCounter() now silently ignore the error and return 0.
They cannot fail with a Python fatal error anymore.
Add py_mach_timebase_info() and win_perf_counter_frequency()
sub-functions.
time.perf_counter() on Windows and time.monotonic() on macOS are now
system-wide. Previously, they used an offset computed at startup to
reduce the precision loss caused by the float type. Use
time.perf_counter_ns() and time.monotonic_ns() added in Python 3.7 to
avoid this precision loss.
On Windows, fix a regression in signal handling which prevented to
interrupt a program using CTRL+C. The signal handler can be run in a
thread different than the Python thread, in which case the test
deciding if the thread can handle signals is wrong.
On Windows, _PyEval_SignalReceived() now always sets eval_breaker to
1 since it cannot test _Py_ThreadCanHandleSignals(), and
eval_frame_handle_pending() always calls
_Py_ThreadCanHandleSignals() to recompute eval_breaker.
* Call _PyTime_Init() and _PyWarnings_InitState() earlier during the
Python initialization.
* Inline _PyImportHooks_Init() into _PySys_InitCore().
* The _warnings initialization function no longer call
_PyWarnings_InitState() to prevent resetting filters_version to 0.
* _PyWarnings_InitState() now returns an int and no longer clear the
state in case of error (it's done anyway at Python exit).
* Rework init_importlib(), fix refleaks on errors.
Fix _PyConfig_Read() if compute_path_config=0: use values set by
Py_SetPath(), Py_SetPythonHome() and Py_SetProgramName(). Add
compute_path_config parameter to _PyConfig_InitPathConfig().
The following functions now return NULL if called before
Py_Initialize():
* Py_GetExecPrefix()
* Py_GetPath()
* Py_GetPrefix()
* Py_GetProgramFullPath()
* Py_GetProgramName()
* Py_GetPythonHome()
These functions no longer automatically computes the Python Path
Configuration. Moreover, Py_SetPath() no longer computes
program_full_path.
The path configuration is now computed in the "main" initialization.
The core initialization no longer computes it.
* Add _PyConfig_Read() function to read the configuration without
computing the path configuration.
* pyinit_core() no longer computes the path configuration: it is now
computed by init_interp_main().
* The path configuration output members of PyConfig are now optional:
* executable
* base_executable
* prefix
* base_prefix
* exec_prefix
* base_exec_prefix
* _PySys_UpdateConfig() now skips NULL strings in PyConfig.
* _testembed: Rename test_set_config() to test_init_set_config() for
consistency with other tests.
Co-authored-by: Lawrence D’Anna <lawrence_danna@apple.com>
* Add support for macOS 11 and Apple Silicon (aka arm64)
As a side effect of this work use the system copy of libffi on macOS, and remove the vendored copy
* Support building on recent versions of macOS while deploying to older versions
This allows building installers on macOS 11 while still supporting macOS 10.9.
* The AST optimiser wasn't descending into named expressions, so
any constant subexpressions weren't being folded at compile time
* Remove "default:" clauses inside the AST optimiser code to reduce the
risk of similar bugs passing unnoticed in future compiler changes
The PyConfig_Read() function now only parses PyConfig.argv arguments
once: PyConfig.parse_argv is set to 2 after arguments are parsed.
Since Python arguments are strippped from PyConfig.argv, parsing
arguments twice would parse the application options as Python
options.
* Rework the PyConfig documentation.
* Fix _testinternalcapi.set_config() error handling.
* SetConfigTests no longer needs parse_argv=0 when restoring the old
configuration.
* Inline _PyInterpreterState_SetConfig(): replace it with
_PyConfig_Copy().
* Add _PyErr_SetFromPyStatus()
* Add _PyInterpreterState_GetConfigCopy()
* Add a new _PyInterpreterState_SetConfig() function.
* Add an unit which gets, modifies, and sets the config.
When Py_Initialize() is called twice, the second call now updates
more sys attributes for the configuration, rather than only sys.argv.
* Rename _PySys_InitMain() to _PySys_UpdateConfig().
* _PySys_UpdateConfig() now modifies sys.flags in-place, instead of
creating a new flags object.
* Remove old commented sys.flags flags (unbuffered and skip_first).
* Add private _PySys_GetObject() function.
* When Py_Initialize(), Py_InitializeFromConfig() and
Replace PyModule_AddObject() with PyModule_AddObjectRef() in the
_warnings module to fix a reference leak on error.
Use also PyModule_AddObjectRef() in importdl.c.
Call _PyAST_Fini() on all interpreters, not only on the main
interpreter. Also, call it ealier to fix a reference leak.
Python types contain a reference to themselves in in their
PyTypeObject.tp_mro member. _PyAST_Fini() must called before the last
GC collection to destroy AST types.
_PyInterpreterState_Clear() now calls _PyAST_Fini(). It now also
calls _PyWarnings_Fini() on subinterpeters, not only on the main
interpreter.
Add an assertion in AST init_types() to ensure that the _ast module
is no longer used after _PyAST_Fini() has been called.
The logging.FileHandler class now keeps a reference to the builtin
open() function to be able to open or reopen the file during Python
finalization.
Fix errors like:
Exception ignored in: (...)
Traceback (most recent call last):
(...)
File ".../logging/__init__.py", line 1463, in error
File ".../logging/__init__.py", line 1577, in _log
File ".../logging/__init__.py", line 1587, in handle
File ".../logging/__init__.py", line 1649, in callHandlers
File ".../logging/__init__.py", line 948, in handle
File ".../logging/__init__.py", line 1182, in emit
File ".../logging/__init__.py", line 1171, in _open
NameError: name 'open' is not defined
The ast module internal state is now per interpreter.
* Rename "astmodulestate" to "struct ast_state"
* Add pycore_ast.h internal header: the ast_state structure is now
declared in pycore_ast.h.
* Add PyInterpreterState.ast (struct ast_state)
* Remove get_ast_state()
* Rename get_global_ast_state() to get_ast_state()
* PyAST_obj2mod() now handles get_ast_state() failures
Enhance the documentation of the Python startup, filesystem encoding
and error handling, locale encoding. Add a new "Python UTF-8 Mode"
section.
* Add "locale encoding" and "filesystem encoding and error handler"
to the glossary
* Remove documentation from Include/cpython/initconfig.h: move it to
Doc/c-api/init_config.rst.
* Doc/c-api/init_config.rst:
* Document command line options and environment variables
* Document default values.
* Add a new "Python UTF-8 Mode" section in Doc/library/os.rst.
* Add warnings to Py_DecodeLocale() and Py_EncodeLocale() docs.
* Document how Python selects the filesystem encoding and error
handler at a single place: PyConfig.filesystem_encoding and
PyConfig.filesystem_errors.
* PyConfig: move orig_argv member at the right place.
This adds a new function named sys._current_exceptions() which is equivalent ot
sys._current_frames() except that it returns the exceptions currently handled
by other threads. It is equivalent to calling sys.exc_info() for each running
thread.
If the nl_langinfo(CODESET) function returns an empty string, Python
now uses UTF-8 as the filesystem encoding.
In May 2010 (commit b744ba1d14), I
modified Python to log a warning and use UTF-8 as the filesystem
encoding (instead of None) if nl_langinfo(CODESET) returns an empty
string.
In August 2020 (commit 94908bbc15), I
modified Python startup to fail with a fatal error and a specific
error message if nl_langinfo(CODESET) returns an empty string. The
intent was to prevent guessing the encoding and also investigate user
configuration where this case happens.
In 10 years (2010 to 2020), I saw zero user report about the error
message related to nl_langinfo(CODESET) returning an empty string.
Today, UTF-8 became the defacto standard and it's safe to make the
assumption that the user expects UTF-8. For example,
nl_langinfo(CODESET) can return an empty string on macOS if the
LC_CTYPE locale is not supported, and UTF-8 is the default encoding
on macOS.
While this change is likely to not affect anyone in practice, it
should make UTF-8 lover happy ;-)
Rewrite also the documentation explaining how Python selects the
filesystem encoding and error handler.
* Rename _Py_GetLocaleEncoding() to _Py_GetLocaleEncodingObject()
* Add _Py_GetLocaleEncoding() which returns a wchar_t* string to
share code between _Py_GetLocaleEncodingObject()
and config_get_locale_encoding().
* _Py_GetLocaleEncodingObject() now decodes nl_langinfo(CODESET)
from the current locale encoding with surrogateescape,
rather than using UTF-8.
Brandt Bucher
Brett Cannon
Mark Shannon
Pablo Galindo
Victor Stinner
Yurii Karabas
Serhiy Storchaka
Christian Heimes
Ronald Oussoren
Nick Coghlan
Julien Danjou