cosmopolitan

mirror of https://github.com/jart/cosmopolitan.git synced 2025-03-02 23:18:44 +00:00

History

Justine Tunney 47a53e143b Productionize new APE loader and more The APE_NO_MODIFY_SELF loader payload has been moved out of the examples folder and improved so that it works on BSD systems, and permits general elf program headers. This brings its quality up enough that it should be acceptable to use by default for many programs, e.g. Python, Lua, SQLite and Python. It's the responsibility of the user to define an appropriate TMPDIR if /tmp is considered an adversarial environment. Mac OS shall be supported by APE_NO_MODIFY_SELF soon. Fixes and improvements have been made to program_executable_name as it's now the one true way to get the absolute path of the executing image. This change fixes a memory leak in linenoise history loading, introduced by performance optimizations in `51904e2687` This change fixes a longstanding regression with Mach system calls, that `23ae9dfceb` back in February which impacted our sched_yield() implementation, which is why no one noticed until now. The Blinkenlights PC emulator has been improved. We now fix rendering on XNU and BSD by not making the assumption that the kernel terminal driver understands UTF8 since that seems to break its internal modeling of \r\n which is now being addressed by using \e[𝑦H instead. The paneling is now more compact in real mode so you won't need to make your font as tiny if you're only emulating an 8086 program. The CLMUL ISA is now emulated too This change also makes improvement to time. CLOCK_MONOTONIC now does the right thing on Windows NT. The nanosecond time module functions added in Python 3.7 have been backported. This change doubles the performance of Argon2 password stretching simply by not using its copy_block and xor_block helper functions, as they were trivial to inline thus resulting in us needing to iterate over each 1024 byte block four fewer times. This change makes code size improvements. _PyUnicode_ToNumeric() was 64k in size and now it's 10k. The CJK codec lookup tables now use lazy delta zigzag deflate (δzd) encoding which reduces their size from 600k to 200k plus the code bloat caused by macro abuse in _decimal.c is now addressed so our fully-loaded statically-linked hermetically-sealed Python virtual interpreter container is now 9.4 megs in the default build mode and 5.5m in MODE=tiny which leaves plenty of room for chibicc. The pydoc web server now accommodates the use case of people who work by SSH'ing into a different machine w/ python.com -m pydoc -p8080 -h0.0.0.0 Finally Python Capsulae delenda est and won't be supported in the future		2021-10-02 08:27:03 -07:00
..
Include	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
Lib	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
Modules	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
Objects	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
Parser	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
PC	Implement tree-shaking for Python sources	2021-09-05 01:20:03 -07:00
Python	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
Tools	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
.gitattributes	Perform build and magnum tuning	2021-08-10 10:26:13 -07:00
freeze.c	Make numerous improvements	2021-09-28 01:52:34 -07:00
hello.py	Make numerous improvements	2021-09-28 01:52:34 -07:00
launch.c	Make numerous improvements	2021-09-28 01:52:34 -07:00
LICENSE	python-3.6.zip added from Github	2021-08-09 05:39:42 -07:00
pycomp.c	Make numerous improvements	2021-09-28 01:52:34 -07:00
pyconfig.h	Fix Pyston speedups (#281 )	2021-10-02 01:28:51 -07:00
pydump.py	Experiment with making Python go faster	2021-08-18 21:57:11 -07:00
pyobj.c	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
python.c	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
python.mk	Productionize new APE loader and more	2021-10-02 08:27:03 -07:00
README.cosmo	Improve ZIP filesystem and change its prefix	2021-08-22 01:11:53 -07:00
README.rst	python-3.6.zip added from Github	2021-08-09 05:39:42 -07:00
repl.c	Fix Pyston speedups (#281 )	2021-10-02 01:28:51 -07:00

README.rst

This is Python version 3.6.14+
==============================

.. image:: https://travis-ci.org/python/cpython.svg?branch=3.6
:alt: CPython build status on Travis CI
:target: https://travis-ci.org/python/cpython

.. image:: https://ci.appveyor.com/api/projects/status/4mew1a93xdkbf5ua/branch/3.6?svg=true
:alt: CPython build status on Appveyor
:target: https://ci.appveyor.com/project/python/cpython/branch/3.6

.. image:: https://dev.azure.com/python/cpython/_apis/build/status/Azure%20Pipelines%20CI?branchName=3.6
:alt: CPython build status on Azure Pipelines
:target: https://dev.azure.com/python/cpython/_build/latest?definitionId=4&branchName=3.6

.. image:: https://codecov.io/gh/python/cpython/branch/3.6/graph/badge.svg
:alt: CPython code coverage on Codecov
:target: https://codecov.io/gh/python/cpython

See the end of this file for further copyright and license information.

General Information
-------------------

- Website: https://www.python.org
- Source code: https://github.com/python/cpython
- Issue tracker: https://bugs.python.org
- Documentation: https://docs.python.org
- Developer's Guide: https://devguide.python.org/

Contributing to CPython
-----------------------

For more complete instructions on contributing to CPython development,
see the `Developer Guide`_.

.. _Developer Guide: https://devguide.python.org/

Using Python
------------

Installable Python kits, and information about using Python, are available at
`python.org`_.

.. _python.org: https://www.python.org/

Build Instructions
------------------

On Unix, Linux, BSD, macOS, and Cygwin::

./configure
make
make test
sudo make install

This will install Python as ``python3``.

You can pass many options to the configure script; run ``./configure --help``
to find out more. On macOS and Cygwin, the executable is called ``python.exe``;
elsewhere it's just ``python``.

If you are running on macOS with the latest updates installed, make sure to install
openSSL or some other SSL software along with Homebrew or another package manager.
If issues persist, see https://devguide.python.org/setup/#macos-and-os-x for more
information.

On macOS, if you have configured Python with ``--enable-framework``, you
should use ``make frameworkinstall`` to do the installation. Note that this
installs the Python executable in a place that is not normally on your PATH,
you may want to set up a symlink in ``/usr/local/bin``.

On Windows, see `PCbuild/readme.txt
<https://github.com/python/cpython/blob/3.6/PCbuild/readme.txt>`_.

If you wish, you can create a subdirectory and invoke configure from there.
For example::

mkdir debug
cd debug
../configure --with-pydebug
make
make test

(This will fail if you *also* built at the top-level directory. You should do
a ``make clean`` at the toplevel first.)

To get an optimized build of Python, ``configure --enable-optimizations``
before you run ``make``. This sets the default make targets up to enable
Profile Guided Optimization (PGO) and may be used to auto-enable Link Time
Optimization (LTO) on some platforms. For more details, see the sections
below.

Profile Guided Optimization
---------------------------

PGO takes advantage of recent versions of the GCC or Clang compilers. If used,
either via ``configure --enable-optimizations`` above or by manually running
``make profile-opt`` regardless of configure flags it will do several steps.

First, the entire Python directory is cleaned of temporary files that may have
resulted in a previous compilation.

Then, an instrumented version of the interpreter is built, using suitable
compiler flags for each flavour. Note that this is just an intermediary step.
The binary resulting from this step is not good for real life workloads as
it has profiling instructions embedded inside.

After this instrumented version of the interpreter is built, the Makefile will
automatically run a training workload. This is necessary in order to profile
the interpreter execution. Note also that any output, both stdout and stderr,
that may appear at this step is suppressed.

Finally, the last step is to rebuild the interpreter, using the information
collected in the previous one. The end result will be a Python binary that is
optimized and suitable for distribution or production installation.

Link Time Optimization
----------------------

Enabled via configure's ``--with-lto`` flag. LTO takes advantage of the
ability of recent compiler toolchains to optimize across the otherwise
arbitrary ``.o`` file boundary when building final executables or shared
libraries for additional performance gains.

What's New
----------

We have a comprehensive overview of the changes in the `What's New in Python
3.6 <https://docs.python.org/3.6/whatsnew/3.6.html>`_ document. For a more
detailed change log, read `Misc/NEWS
<https://github.com/python/cpython/blob/3.6/Misc/NEWS.d>`_, but a full
accounting of changes can only be gleaned from the `commit history
<https://github.com/python/cpython/commits/3.6>`_.

If you want to install multiple versions of Python see the section below
entitled "Installing multiple versions".

Documentation
-------------

`Documentation for Python 3.6 <https://docs.python.org/3.6/>`_ is online,
updated daily.

It can also be downloaded in many formats for faster access. The documentation
is downloadable in HTML, PDF, and reStructuredText formats; the latter version
is primarily for documentation authors, translators, and people with special
formatting requirements.

For information about building Python's documentation, refer to `Doc/README.rst
<https://github.com/python/cpython/blob/3.6/Doc/README.rst>`_.

Converting From Python 2.x to 3.x
---------------------------------

Significant backward incompatible changes were made for the release of Python
3.0, which may cause programs written for Python 2 to fail when run with Python
3. For more information about porting your code from Python 2 to Python 3, see
the `Porting HOWTO <https://docs.python.org/3/howto/pyporting.html>`_.

Testing
-------

To test the interpreter, type ``make test`` in the top-level directory. The
test set produces some output. You can generally ignore the messages about
skipped tests due to optional features which can't be imported. If a message
is printed about a failed test or a traceback or core dump is produced,
something is wrong.

By default, tests are prevented from overusing resources like disk space and
memory. To enable these tests, run ``make testall``.

If any tests fail, you can re-run the failing test(s) in verbose mode. For
example, if ``test_os`` and ``test_gdb`` failed, you can run::

make test TESTOPTS="-v test_os test_gdb"

If the failure persists and appears to be a problem with Python rather than
your environment, you can `file a bug report <https://bugs.python.org>`_ and
include relevant output from that command to show the issue.

See `Running & Writing Tests <https://devguide.python.org/runtests/>`_
for more on running tests.

Installing multiple versions
----------------------------

On Unix and Mac systems if you intend to install multiple versions of Python
using the same installation prefix (``--prefix`` argument to the configure
script) you must take care that your primary python executable is not
overwritten by the installation of a different version. All files and
directories installed using ``make altinstall`` contain the major and minor
version and can thus live side-by-side. ``make install`` also creates
``${prefix}/bin/python3`` which refers to ``${prefix}/bin/pythonX.Y``. If you
intend to install multiple versions using the same prefix you must decide which
version (if any) is your "primary" version. Install that version using ``make
install``. Install all other versions using ``make altinstall``.

For example, if you want to install Python 2.7, 3.5, and 3.6 with 3.6 being the
primary version, you would execute ``make install`` in your 3.6 build directory
and ``make altinstall`` in the others.

Issue Tracker and Mailing List
------------------------------

Bug reports are welcome! You can use the `issue tracker
<https://bugs.python.org>`_ to report bugs, and/or submit pull requests `on
GitHub <https://github.com/python/cpython>`_.

You can also follow development discussion on the `python-dev mailing list
<https://mail.python.org/mailman/listinfo/python-dev/>`_.

Proposals for enhancement
-------------------------

If you have a proposal to change Python, you may want to send an email to the
comp.lang.python or `python-ideas`_ mailing lists for initial feedback. A
Python Enhancement Proposal (PEP) may be submitted if your idea gains ground.
All current PEPs, as well as guidelines for submitting a new PEP, are listed at
`python.org/dev/peps/ <https://www.python.org/dev/peps/>`_.

.. _python-ideas: https://mail.python.org/mailman/listinfo/python-ideas/

Release Schedule
----------------

See :pep:`494` for Python 3.6 release details.

See the file "LICENSE" for information on the history of this software, terms &
conditions for usage, and a DISCLAIMER OF ALL WARRANTIES.

This Python distribution contains *no* GNU General Public License (GPL) code,
so it may be used in proprietary projects. There are interfaces to some GNU
code but these are entirely optional.

All trademarks referenced herein are property of their respective holders.