* _PyPreConfig_Write() now reallocates the pre-configuration with the
  new memory allocator.
* It is no longer needed to force the "default raw memory allocator"
  to clear pre-configuration and core configuration. Simplify the
  code.
* _PyPreConfig_Write() now does nothing if called after
  Py_Initialize(): no longer check if the allocator is the same.
* Remove _PyMem_GetDebugAllocatorsName(): dev mode sets again
  allocator to "debug".

* _PyPreConfig_Write() now sets the memory allocator.
* _PyPreConfig_Write() gets a return type: _PyInitError.
* _Py_InitializeCore() now reads and writes the pre-configuration
  (set the memory allocator, configure the locale) before reading and
  writing the core configuration.

The development mode now uses the effective name of the debug memory
allocator ("pymalloc_debug" or "malloc_debug"). So the name doesn't
change after setting the memory allocator.

NamedStore has been replaced with Store. The difference between
NamedStore and Store is handled when precess the NamedExpr node
one level upper.

Correctly fixes bpo-36197.

* Move 'allocator' and 'dev_mode' fields from _PyCoreConfig
  to _PyPreConfig.
* Fix InitConfigTests of test_embed: dev_mode sets allocator to
  "debug", add a new tests for env vars with dev mode enabled.

Cast function pointers to (void(*)(void)) before casting to (PyCFunction)
to make "warning: cast between incompatible function types" false alarm quiet.

* Move following fields from _PyCoreConfig to _PyPreConfig:

  * coerce_c_locale
  * coerce_c_locale_warn
  * legacy_windows_stdio
  * utf8_mode

* _PyPreConfig_ReadFromArgv() is now responsible to choose the
  filesystem encoding
* _PyPreConfig_Write() now sets the LC_CTYPE locale

Methods are always bound, and `__self__` can no longer be `NULL`
(`method_new()` and `PyMethod_New()` both explicitly check for this).

Moreover, once a bound method is bound, it *stays* bound and won't be re-bound
to something else, so the section in the datamodel that talks about accessing
an methods in a different descriptor-binding context doesn't apply any more in
Python 3.

For command line option, `option` is better than `parameter`.

The new function is now responsible to parse -E and -I command line
arguments.

* Add _PyPreConfig structure
* Move 'ignored' and 'use_environment' fields from _PyCoreConfig
  to _PyPreConfig
* Add a new "_PyPreConfig preconfig;" field to _PyCoreConfig

Fix two unlikely reference leaks in _hashopenssl. The leaks only occur in
out-of-memory cases. Thanks to Charalampos Stratakis.
Signed-off-by: Christian Heimes <christian@python.org>



https://bugs.python.org/issue36179

For C++ extensions, distutils tries to replace the C compiler with the
C++ compiler, but it assumes that C compiler is the first element after
any environment variables set. On AIX, linking goes through ld_so_aix,
so it is the first element and the compiler is the next element. Thus
the replacement is faulty:

ld_so_aix gcc ... -> g++ gcc ...

Also, it assumed that self.compiler_cxx had only 1 element or that
there were the same number of elements as the linker has and in the
same order. This might not be the case, so instead concatenate
everything together.

Revert: bpo-33608: Factor out a private, per-interpreter _Py_AddPendingCall(). (GH-11617) (GH-12159)

* Revert "bpo-36097: Use only public C-API in the_xxsubinterpreters module (adding as necessary). (#12003)"

This reverts commit bcfa450f.

* Revert "bpo-33608: Simplify ceval's DISPATCH by hoisting eval_breaker ahead of time. (gh-12062)"

This reverts commit bda918bf.

* Revert "bpo-33608: Use _Py_AddPendingCall() in _PyCrossInterpreterData_Release(). (gh-12024)"

This reverts commit b05b711a.

* Revert "bpo-33608: Factor out a private, per-interpreter _Py_AddPendingCall(). (GH-11617)"

This reverts commit ef4ac967.

Use UTF-8 as the system encoding on VxWorks.

The main reason are:

1. The locale is frequently misconfigured.
2. Missing some functions to deal with locale in VxWorks C library.

* bpo-20906: Corrections & revisions to Unicode HOWTO

* bpo-34484: don't describe range as a Private Use Area

Co-authored-by: Maxwell <maxwellpxt@gmail.com>
Co-authored-by: Stéphane Wirtel <stephane@wirtel.be>





https://bugs.python.org/issue35899

The 3.8 docs claim that `os.posix_spawn` was introduced in 3.7, but it wasn't; it will be introduced in 3.8.

Bug introduced by 848037c1.

The previous code hardcoded `SEEK_SET`, etc. While it's very unlikely
that these values will change, it's best to use the definitions to avoid
there being mismatches in behavior with the code in the future.
Signed-off-by: Enji Cooper <yaneurabeya@gmail.com>

It is changed from 16KiB to 64KiB.  The previous default value
is used since 1990.

coreutils chose 128 KiB as minimum buffer size for block device I/O.

But shutil.copyfileobj() can be used for non block devices.
So I choose more conservative value.

As my quick benchmark, performance difference between 64KiB and
128 KiB is up to ~5%.  On the other hand, performance difference
between 32 KiB and 64 KiB can be more than 10% when file is fully
buffered.

This is why 64 KiB is rational value.

Pgen is the oldest piece of technology in the CPython repository, building it requires various #if[n]def PGEN hacks in other parts of the code and it also depends more and more on CPython internals. This commit removes the old pgen C code and replaces it for a new version implemented in pure Python. This is a modified and adapted version of lib2to3/pgen2 that can generate grammar files compatibles with the current parser.

This commit also eliminates all the #ifdef and code branches related to pgen, simplifying the code and making it more maintainable. The regen-grammar step now uses $(PYTHON_FOR_REGEN) that can be any version of the interpreter, so the new pgen code maintains compatibility with older versions of the interpreter (this also allows regenerating the grammar with the current CI solution that uses Python3.5). The new pgen Python module also makes use of the Grammar/Tokens file that holds the token specification, so is always kept in sync and avoids having to maintain duplicate token definitions.

 Patch by Kevin Walzer.

https://bugs.python.org/issue36043

This includes fixes to various _Py_atomic_* macros.

Add TEST_EXTENSIONS constant to setup.py to allow to not build test
extensions like _testcapi.

Changes:

* Add add_ldflags_cppflags() subfunction
* Rename add_compiler_directories() to configure_compiler().
* Remove unused COMPILED_WITH_PYDEBUG constant.
* Use self.add() rather than accessing directly self.extensions.
* Remove module_enabled() function: check differently if curses
  extension is built or not.

Ensure custom formatwarning function can receive line as positional argument.
Co-Authored-By: Tashrif Billah <tashrifbillah@gmail.com>

* Add _PyArgv_Decode() function
* Move _Py_ClearFileSystemEncoding() and _Py_SetFileSystemEncoding()
  to preconfig.c.

* Move set_compiler_flags() calls and concurrent.future hack from
  module top-level to main()
* Remove unused variables 'macros' and 'libraries' from
  detect_multiprocessing().
* Move SUMMARY and CLASSIFIERS constants at the top, move
  set_compiler_flags() function below these constants.
* Add some empty new lines to respect PEP 8.