Doing this provides significant performance gains for runtime startup (~15% with all the imported modules frozen). We don't yet freeze all the imported modules because there are a few hiccups in the build systems we need to sort out first. (See bpo-45186 and bpo-45188.)
Note that in PR GH-28320 we added a command-line flag (-X frozen_modules=[on|off]) that allows users to opt out of (or into) using frozen modules. The default is still "off" but we will change it to "on" as soon as we can do it in a way that does not cause contributors pain.
https://bugs.python.org/issue45020
Currently we freeze several modules into the runtime. For each of these modules it is essential to bootstrapping the runtime that they be frozen. Any other stdlib module that we later freeze into the runtime is not essential. We can just as well import from the .py file. This PR lets users explicitly choose which should be used, with the new "-X frozen_modules=[on|off]" CLI flag. The default is "off" for now.
https://bugs.python.org/issue45020
In the configparser module, these have been deprecated since Python 3.2:
* the SafeConfigParser class,
* the filename property of the ParsingError class,
* the readfp method of the ConfigParser class,
* Constructors of subclasses of some buitin classes (e.g. tuple, list,
frozenset) no longer accept arbitrary keyword arguments.
* Subclass of set can now define a __new__() method with additional
keyword parameters without overriding also __init__().
* Calling guess_all_extensions() with strict=False potentially
mutated types_map_inv.
* Mutating the result of guess_all_extensions() mutated types_map_inv.
Due to significant security concerns, the reuse_address parameter of
asyncio.loop.create_datagram_endpoint, deprecated in Python 3.9, is
now removed. This is because of the behavior of the socket option
SO_REUSEADDR in UDP.
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
Remove deprecated __getitem__ methods of xml.dom.pulldom.DOMEventStream,
wsgiref.util.FileWrapper and fileinput.FileInput, deprecated since Python 3.9.
open(), io.open(), codecs.open() and fileinput.FileInput no longer
accept "U" ("universal newline") in the file mode. This flag was
deprecated since Python 3.3.
The binhex module, deprecated in Python 3.9, is now removed. The
following binascii functions, deprecated in Python 3.9, are now also
removed:
* a2b_hqx(), b2a_hqx();
* rlecode_hqx(), rledecode_hqx().
The binascii.crc_hqx() function remains available.
libregrtest now clears the type cache later to reduce the risk of
false alarm when checking for reference leaks. Previously, the type
cache was cleared too early and libregrtest raised a false alarm
about reference leaks under very specific conditions.
Move also support.gc_collect() outside clear/cleanup functions to
make the garbage collection more explicit.
Co-authored-by: Irit Katriel <1055913+iritkatriel@users.noreply.github.com>
Nikita Sobolev
Eric Snow
junyixie
Benjamin Peterson
Victor Stinner
Irit Katriel
Hugo van Kemenade
Serhiy Storchaka
Henry-Joseph Audéoud
Raymond Hettinger
Erlend Egeberg Aasland
Yurii Karabas
Pablo Galindo Salgado
Brandt Bucher
Batuhan Taskaya
Ruben Vorderman
Inada Naoki
Dong-hee Na
Miguel Brito