[3.13] gh-130940: Remove PyConfig.use_system_logger #131129

freakboy3742 · 2025-03-12T04:14:19Z

Pull request #127754 is a backport of #127592 to the 3.13 branch. However, this PR included a new attribute (use_system_logger) in PyConfig, which broke ABI compatibility on Apple platforms (macOS and iOS).

This was not detected because ABI compatibility checks are only performed on Linux, and the inclusion of the flag was gated with __APPLE__ preprocessor handling.

On macOS, removing the flag is no problem - it's a new feature, but an entirely optional one that would only be enabled by someone that has built (or updated) an app that embeds Python 3.13.2.

However, on iOS, the behavior enabled by this flag is required on iOS so that the logs generated by the simulator can be observed at all. More generally, there's very little reason that you'd not want stdout and stderr routed to the system log - every BeeWare app, for example, includes std-nslog, which implements effectively the same behavior.

This PR:

Removes the use_system_logger attribute from PyConfig.
Hard-codes the use of the system logger on iOS only.

This is, strictly, a change of behavior for 3.13 on iOS, unless you view "the output of Python's stdout/stderr is now visible in the app logs" as a bug that is resolved by this PR. My inclination is that this is such a signficant quality of life for iOS developers that it warrants being treated as a bugfix/improvement - but I wanted to flag the change in the strictest interpretation.

In an upcoming PR, I'll rework the introduction of the flag on the 3.14 branch to use the new PyInitConfig API (avoiding the ABI incompatibility), making the default value "enabled" on iOS, and "disabled" on macOS.

Issue: Backport of PyConfig.use_system_logger has changed ABI in a patch 3.13.1 -> 3.13.2 #130940

📚 Documentation preview 📚: https://cpython-previews--131129.org.readthedocs.build/

freakboy3742 · 2025-03-12T04:15:00Z

!buildbot iOS

bedevere-bot · 2025-03-12T04:15:02Z

🤖 New build scheduled with the buildbot fleet by @freakboy3742 for commit 98b0415 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F131129%2Fmerge

The command will test the builders whose names match following regular expression: iOS

The builders matched are:

iOS ARM64 Simulator PR

vstinner · 2025-03-12T06:25:19Z

Misc/NEWS.d/next/Library/2025-03-12-11-53-32.gh-issue-130940.81K1Tg.rst

@@ -0,0 +1,4 @@
+The ``PyConfig.use_system_logger`` attribute, introduced in Python 3.12.2, has


This change is for Python 3.13. Do you mean Python 3.13.2?

🤦 I did.

Misc/NEWS.d/next/Library/2025-03-12-11-53-32.gh-issue-130940.81K1Tg.rst

vstinner

LGTM

freakboy3742 · 2025-03-12T06:38:36Z

@ned-deily Although @vstinner has approved this, I'm holding off merging until I get your signoff as a macOS/iOS platform delegate, because of the implications on iOS stdout logging.

ned-deily · 2025-03-12T06:45:54Z

I’ll review it tomorrow.

ned-deily

LGTM, and all tests pass in the simulator. Thanks for taking this on.

bedevere-bot · 2025-03-13T04:08:50Z

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot aarch64 Android 3.13 (tier-3) has failed when building commit 589f422.

What do you need to do:

Don't panic.
Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1590/builds/504) and take a look at the build logs.
Check if the failure is related to this commit (589f422) or if it is a false positive.
If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1590/builds/504

Failed tests:

test_os

Failed subtests:

test_fpathconf - test.test_os.TestInvalidFD.test_fpathconf

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last):
  File "/data/user/0/org.python.testbed/files/python/lib/python3.13/test/test_os.py", line 2402, in test_fpathconf
    self.check(os.pathconf, "PC_NAME_MAX")
    ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/user/0/org.python.testbed/files/python/lib/python3.13/test/test_os.py", line 2325, in check
    f(os_helper.make_bad_fd(), *args, **kwargs)
    ~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: unrecognized configuration name

bedevere-bot · 2025-03-13T04:33:44Z

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot aarch64 RHEL8 LTO 3.13 (tier-2) has failed when building commit 589f422.

What do you need to do:

Don't panic.
Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1393/builds/601) and take a look at the build logs.
Check if the failure is related to this commit (589f422) or if it is a false positive.
If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1393/builds/601

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-aarch64.lto/build/Lib/threading.py", line 1041, in _bootstrap_inner
    self.run()
    ~~~~~~~~^^
  File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-aarch64.lto/build/Lib/threading.py", line 992, in run
    self._target(*self._args, **self._kwargs)
    ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-aarch64.lto/build/Lib/test/test_interpreters/test_stress.py", line 47, in run
    interp = interpreters.create()
  File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-aarch64.lto/build/Lib/test/support/interpreters/__init__.py", line 76, in create
    id = _interpreters.create(reqrefs=True)
interpreters.InterpreterError: interpreter creation failed
k


Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-aarch64.lto/build/Lib/threading.py", line 1041, in _bootstrap_inner
    self.run()
    ~~~~~~~~^^
  File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-aarch64.lto/build/Lib/threading.py", line 992, in run
    self._target(*self._args, **self._kwargs)
    ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-aarch64.lto/build/Lib/test/test_interpreters/test_stress.py", line 30, in task
    interp = interpreters.create()
  File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-aarch64.lto/build/Lib/test/support/interpreters/__init__.py", line 76, in create
    id = _interpreters.create(reqrefs=True)
interpreters.InterpreterError: interpreter creation failed
k

freakboy3742 · 2025-03-13T06:21:37Z

Both CI failures appear to be unrelated. The Android test has passed on a re-run.

) Removes ``PyConfig.use_system_logger``, resolving an ABI incompatibility introduced in 3.13.2. Changes the default behavior of iOS to *always* direct stdout/stderr to the system log.

Removes ``PyConfig.use_system_logger``, resolving an ABI incompatibility introduced in 3.13.2. Changes the default behavior of iOS to *always* direct stdout/stderr to the system log.

Remove PyConfig.use_system_logger.

98b0415

freakboy3742 requested review from vstinner and ned-deily March 12, 2025 04:14

freakboy3742 requested a review from ericsnowcurrently as a code owner March 12, 2025 04:14

bedevere-app bot added the awaiting core review label Mar 12, 2025

bedevere-app bot mentioned this pull request Mar 12, 2025

Backport of PyConfig.use_system_logger has changed ABI in a patch 3.13.1 -> 3.13.2 #130940

Closed

freakboy3742 added OS-mac OS-ios labels Mar 12, 2025

vstinner reviewed Mar 12, 2025

View reviewed changes

freakboy3742 commented Mar 12, 2025

View reviewed changes

Misc/NEWS.d/next/Library/2025-03-12-11-53-32.gh-issue-130940.81K1Tg.rst Outdated Show resolved Hide resolved

Correct Python version number reference.

3c9bb71

vstinner approved these changes Mar 12, 2025

View reviewed changes

bedevere-app bot added awaiting merge and removed awaiting core review labels Mar 12, 2025

freakboy3742 mentioned this pull request Mar 12, 2025

gh-130940: Modify default behavior of PyConfig.use_system_logger to enable on iOS #131172

Merged

ned-deily approved these changes Mar 13, 2025

View reviewed changes

freakboy3742 merged commit 589f422 into python:3.13 Mar 13, 2025
39 checks passed

bedevere-app bot removed the awaiting merge label Mar 13, 2025

freakboy3742 deleted the remove-system-log branch March 13, 2025 03:53

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

[3.13] gh-130940: Remove PyConfig.use_system_logger #131129

[3.13] gh-130940: Remove PyConfig.use_system_logger #131129

freakboy3742 commented Mar 12, 2025 •

edited

Loading

freakboy3742 commented Mar 12, 2025

bedevere-bot commented Mar 12, 2025

vstinner Mar 12, 2025

freakboy3742 Mar 12, 2025

vstinner left a comment

freakboy3742 commented Mar 12, 2025

ned-deily commented Mar 12, 2025

ned-deily left a comment

bedevere-bot commented Mar 13, 2025

bedevere-bot commented Mar 13, 2025

freakboy3742 commented Mar 13, 2025

		@@ -0,0 +1,4 @@
		The ``PyConfig.use_system_logger`` attribute, introduced in Python 3.12.2, has

[3.13] gh-130940: Remove PyConfig.use_system_logger #131129

[3.13] gh-130940: Remove PyConfig.use_system_logger #131129

Conversation

freakboy3742 commented Mar 12, 2025 • edited Loading

freakboy3742 commented Mar 12, 2025

bedevere-bot commented Mar 12, 2025

vstinner Mar 12, 2025

Choose a reason for hiding this comment

freakboy3742 Mar 12, 2025

Choose a reason for hiding this comment

vstinner left a comment

Choose a reason for hiding this comment

freakboy3742 commented Mar 12, 2025

ned-deily commented Mar 12, 2025

ned-deily left a comment

Choose a reason for hiding this comment

bedevere-bot commented Mar 13, 2025

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

bedevere-bot commented Mar 13, 2025

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

freakboy3742 commented Mar 13, 2025

freakboy3742 commented Mar 12, 2025 •

edited

Loading