* Revert "bpo-34589: Add -X coerce_c_locale command line option (GH-9378)"

This reverts commit dbdee007.

* Revert "bpo-34589: C locale coercion off by default (GH-9073)"

This reverts commit 7a0791b6.

* Revert "bpo-34589: Make _PyCoreConfig.coerce_c_locale private (GH-9371)"

This reverts commit 188ebfa4.

They were specific to the C implementation.

A couple of fixes here to make this more PEP-8:

* Avoid multiple statements on one line with `;` statement separator -- this is very rare in Python and is "generally discouraged" in PEP 8 (and if used, per PEP 8 there shouldn't be a space before the `;`)
* Add output for the first "Formatted String Literals" example. (Side note: are the doctests for this being run? If so, why didn't it fail?)
* Avoid space before `!r`. I have generally not seen spaces before the `!`, and this also matches the style used in the docs here: https://docs.python.org/3/library/string.html#format-string-syntax



https://bugs.python.org/issue34712

`list.append([], None)` was profiled but `list.append([], None, **{})` was not profiled.
Enable profiling for later case.

https://bugs.python.org/issue34125

Follow up to 2a9c3805 (bpo-34585).

Currently configure.ac uses AC_RUN_IFELSE to determine the byte order of doubles, but this silently fails under cross compilation and Python doesn't do floats properly.

Instead, steal a macro from autoconf-archive which compiles code using magic doubles (which encode to ASCII) and grep for the representation in the binary.

RFC because this doesn't yet handle the weird ancient ARMv4 OABI 'mixed-endian' encoding properly. This encoding is ancient and I don't believe the union of "Python 3.8 users" and "OABI users" has anything in. Should the support for this just be dropped too? Alternatively, someone will need to find an OABI toolchain to verify the encoding of the magic double.

Co-authored-by: Elvis Pranskevichus <elvis@magic.io>

The docs were ambiguous about whether you pass in a coroutine function
or a coroutine object, e.g. is it:

  aestack.push_async_exit(some_async_func)

or

  aestack.push_async_exit(some_async_func())

(It's the first one.)

This makes streamed zips compatible with MacOS Archive Utility and
other applications.

The C accelerated _elementtree module now initializes hash randomization
salt from _Py_HashSecret instead of libexpat's default CPRNG.
Signed-off-by: Christian Heimes <christian@python.org>



https://bugs.python.org/issue34623

 bpo-33721: Make some os.path functions and pathlib.Path methods be tolerant to invalid paths.  (#7695)

Such functions as os.path.exists(), os.path.lexists(), os.path.isdir(),
os.path.isfile(), os.path.islink(), and os.path.ismount() now return False
instead of raising ValueError or its subclasses UnicodeEncodeError
and UnicodeDecodeError for paths that contain characters or bytes
unrepresentative at the OS level.

Add C API function PyCompile_OpcodeStackEffectWithJump().

Also rename corresponding attributes, parameters and variables.

The `gather` method requires to close the parenthesis, but it is being closed twice.

Add a new -X coerce_c_locale command line option to control C locale
coercion (PEP 538).

Py_Initialize() and Py_Main() cannot enable the C locale coercion
(PEP 538) anymore: it is always disabled. It can now only be enabled
by the Python program ("python3).

test_embed: get_filesystem_encoding() doesn't have to set PYTHONUTF8
nor PYTHONCOERCECLOCALE, these variables are already set in the
parent.

_PyCoreConfig:

* Rename coerce_c_locale to _coerce_c_locale
* Rename coerce_c_locale_warn to _coerce_c_locale_warn

These fields are now private (name prefixed by "_").

The test tries to fill the receiver's socket buffer and expects an
error. But the RDS protocol doesn't require that. Moreover, the Linux
implementation of RDS expects that the producer of the messages
reduces its rate, it's not the role of the receiver to trigger an
error.

The test fails on Fedora 28 by design, so remove it.

This reverts commit afde1c1a.

Also convert os.get_blocking() and os.set_blocking().