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gh-135228: When @dataclass(slots=True) replaces a dataclass, make the original class collectible (take 2)#137047

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encukou merged 9 commits into
python:mainfrom
JelleZijlstra:dataclasses-hack-v2
Aug 12, 2025
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gh-135228: When @dataclass(slots=True) replaces a dataclass, make the original class collectible (take 2)#137047
encukou merged 9 commits into
python:mainfrom
JelleZijlstra:dataclasses-hack-v2

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@JelleZijlstra

@JelleZijlstra JelleZijlstra commented Jul 23, 2025 •
edited by bedevere-app Bot
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This is a redo of #136893 without relying on a hack to get to the type dictionary.

JelleZijlstra and others added 3 commits July 23, 2025 08:13
@JelleZijlstra @ncoghlan
pythongh-135228: When @DataClass(slots=True) replaces a dataclass, ma… …
916ce1b 
…ke the original class collectible (python#136893)

An interesting hack, but more localized in scope than python#135230.

This may be a breaking change if people intentionally keep the original class around
when using `@dataclass(slots=True)`, and then use `__dict__` or `__weakref__` on the
original class.

Co-authored-by: Alyssa Coghlan <ncoghlan@gmail.com>
@JelleZijlstra
Use a new private sys function instead
6dc0f48
@JelleZijlstra
obsolete comment
b9fb155
@JelleZijlstra JelleZijlstra added the needs backport to 3.14 bugs and security fixes label Jul 23, 2025
@bedevere-app bedevere-app Bot mentioned this pull request Jul 23, 2025
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serhiy-storchaka
serhiy-storchaka reviewed Jul 23, 2025
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Can we check that this is a Python class? Should we clear the whole class dict or set it to NULL for the case if there are more descriptors?

@JelleZijlstra

JelleZijlstra commented Jul 23, 2025

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Can we check that this is a Python class?

Maybe we can check that it's a heap type?

Should we clear the whole class dict or set it to NULL for the case if there are more descriptors?

I'm not aware of other descriptors that could cause problems. It's better to minimize the amount of changes we make to the class, because there are edge cases where the class is still accessible after the dataclass transformation is applied.

@JelleZijlstra @encukou @serhiy-storchaka
Apply suggestions from code review …
a9483b4 
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
@JelleZijlstra

JelleZijlstra commented Aug 5, 2025

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@encukou @serhiy-storchaka could you review again and approve if you're satisfied, so that we can get this fixed in 3.14?

encukou
encukou reviewed Aug 5, 2025
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I can't find any issues in the PR; this is pretty much is the local optimum.
But, I can't tell if there will be unintended consequences. This PR feels quite risky for a RC fix.

Docs-wise: the notes/comments shouldn't imply that the original class is guaranteed to be garbage collected -- something else could still keep it alive.

@encukou

encukou commented Aug 11, 2025

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@hugovk Your thoughts on this?

IMO: If we weren't in RC period, I'd push for #136966, which is IMO a (slight) improvement on its own. But, it has a higher risk of unknown unknowns.
For backporting to 3.14.0, this dataclasses-specific workaround is probably better. But, all of it is a band-aid.

serhiy-storchaka
serhiy-storchaka approved these changes Aug 11, 2025
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I agree with @encukou. #136966 may be better in long perspective (or it may be a move in right direction), but this change has more limited impact, and therefore lokks safer. We always can backport #136966 if we test it well.

@JelleZijlstra

JelleZijlstra commented Aug 12, 2025

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I also agree that #136966 is a better long-term solution; we can merge it into 3.15 after this goes in, and we can also consider using it in 3.14.1.

@encukou

encukou commented Aug 12, 2025

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Let's go then.

Hide details View details @encukou encukou merged commit 6859b95 into python:main Aug 12, 2025
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@miss-islington-app

miss-islington-app Bot commented Aug 12, 2025

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Thanks @JelleZijlstra for the PR, and @encukou for merging it 🌮🎉.. I'm working now to backport this PR to: 3.14.
🐍🍒⛏🤖

miss-islington pushed a commit to miss-islington/cpython that referenced this pull request Aug 12, 2025
@JelleZijlstra @ncoghlan
@encukou @serhiy-storchaka @miss-islington
pythongh-135228: When @DataClass(slots=True) replaces a dataclass, ma… …
d764eb6 
…ke the original class collectible (take 2) (pythonGH-137047)

Remove the `__dict__` and `__weakref__` descriptors from the original class when creating a dataclass from it.

An interesting hack, but more localized in scope than pythongh-135230.

This may be a breaking change if people intentionally keep the original class around
when using `@dataclass(slots=True)`, and then use `__dict__` or `__weakref__` on the
original class.

(cherry picked from commit 6859b95)

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Alyssa Coghlan <ncoghlan@gmail.com>
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
@bedevere-app

bedevere-app Bot commented Aug 12, 2025

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GH-137666 is a backport of this pull request to the 3.14 branch.

@bedevere-app bedevere-app Bot removed the needs backport to 3.14 bugs and security fixes label Aug 12, 2025
@hugovk

hugovk commented Aug 12, 2025 •
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Thanks all, let's do this fix for RC2 -- I'll merge the backport #137666 once tests pass and it's approved.

And do #136966 for 3.15 and possibly 3.14.1.

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⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot aarch64 Fedora Stable LTO + PGO 3.x (tier-2) has failed when building commit 6859b95.

What do you need to do:

  1. Don't panic.
  2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
  3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/524/builds/8141) and take a look at the build logs.
  4. Check if the failure is related to this commit (6859b95) or if it is a false positive.
  5. 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/524/builds/8141

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

Click to see traceback logs 
remote: Enumerating objects: 14, done.        
remote: Counting objects:   9% (1/11)        
remote: Counting objects:  18% (2/11)        
remote: Counting objects:  27% (3/11)        
remote: Counting objects:  36% (4/11)        
remote: Counting objects:  45% (5/11)        
remote: Counting objects:  54% (6/11)        
remote: Counting objects:  63% (7/11)        
remote: Counting objects:  72% (8/11)        
remote: Counting objects:  81% (9/11)        
remote: Counting objects:  90% (10/11)        
remote: Counting objects: 100% (11/11)        
remote: Counting objects: 100% (11/11), done.        
remote: Compressing objects:  11% (1/9)        
remote: Compressing objects:  22% (2/9)        
remote: Compressing objects:  33% (3/9)        
remote: Compressing objects:  44% (4/9)        
remote: Compressing objects:  55% (5/9)        
remote: Compressing objects:  66% (6/9)        
remote: Compressing objects:  77% (7/9)        
remote: Compressing objects:  88% (8/9)        
remote: Compressing objects: 100% (9/9)        
remote: Compressing objects: 100% (9/9), done.        
remote: Total 14 (delta 2), reused 2 (delta 2), pack-reused 3 (from 1)        
From https://github.com/python/cpython
 * branch                    main       -> FETCH_HEAD
Note: switching to '6859b95cfff26c9ef52c5535d2b3662f17ff5b3d'.

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by switching back to a branch.

If you want to create a new branch to retain commits you create, you may
do so (now or later) by using -c with the switch command. Example:

  git switch -c <new-branch-name>

Or undo this operation with:

  git switch -

Turn off this advice by setting config variable advice.detachedHead to false

HEAD is now at 6859b95cfff gh-135228: When @dataclass(slots=True) replaces a dataclass, make the original class collectible (take 2) (GH-137047)
Switched to and reset branch 'main'

find: ‘build’: No such file or directory
find: ‘build’: No such file or directory
find: ‘build’: No such file or directory
find: ‘build’: No such file or directory
make[2]: [Makefile:3379: clean-retain-profile] Error 1 (ignored)
Python/ceval.c: In function ‘_PyEvalFramePushAndInit_Ex’:
Python/ceval.c:1917:38: warning: ‘stack_array’ may be used uninitialized [-Wmaybe-uninitialized]
 1917 |     _PyInterpreterFrame *new_frame = _PyEvalFramePushAndInit(
      |                                      ^~~~~~~~~~~~~~~~~~~~~~~~
 1918 |         tstate, func, locals,
      |         ~~~~~~~~~~~~~~~~~~~~~         
 1919 |         newargs, nargs, kwnames, previous
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 1920 |     );
      |     ~                                 
Python/ceval.c:1840:1: note: by argument 4 of type ‘const union _PyStackRef *’ to ‘_PyEvalFramePushAndInit’ declared here
 1840 | _PyEvalFramePushAndInit(PyThreadState *tstate, _PyStackRef func,
      | ^~~~~~~~~~~~~~~~~~~~~~~
Python/ceval.c:1886:17: note: ‘stack_array’ declared here
 1886 |     _PyStackRef stack_array[8];
      |                 ^~~~~~~~~~~
/usr/bin/ld: error in /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o)(.eh_frame); no .eh_frame_hdr table will be created
/usr/bin/ld: error in /usr/lib/gcc/aarch64-redhat-linux/15/libgcc.a(sync-cache.o)(.eh_frame); no .eh_frame_hdr table will be created
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 1090522845 >= 662 for section `.strtab'
/usr/bin/ld: /usr/lib/gcc/aarch64-redhat-linux/15/libgcov.a(_gcov.o): invalid string offset 3236147 >= 662 for section `.strtab'
collect2: fatal error: ld terminated with signal 11 [Segmentation fault], core dumped
compilation terminated.
make[2]: *** [Makefile:1146: python] Error 1
make[1]: *** [Makefile:1005: profile-gen-stamp] Error 2
make: *** [Makefile:1017: profile-run-stamp] Error 2

@hugovk

hugovk commented Aug 12, 2025

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Same buildbot passed on the backport:

hugovk pushed a commit that referenced this pull request Aug 12, 2025
@miss-islington @JelleZijlstra
@ncoghlan @encukou @serhiy-storchaka
[3.14] gh-135228: When @DataClass(slots=True) replaces a dataclass, m… …
4dda176 
…ake the original class collectible (take 2) (GH-137047) (#137666)

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Alyssa Coghlan <ncoghlan@gmail.com>
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
@encukou encukou mentioned this pull request Aug 12, 2025
Merged
maurycy added a commit to maurycy/cpython that referenced this pull request Aug 12, 2025
@maurycy
Merge branch 'main' into csv-sniffer-counter-set …
11c891d 
* main:
  pythongh-137288: Update 3.14 magic numbers (pythonGH-137665)
  pythongh-135228: When @DataClass(slots=True) replaces a dataclass, make the original class collectible (take 2) (pythonGH-137047)
  pythongh-126008: Improve docstrings for Tkinter cget and configure methods (pythonGH-133303)
  pythongh-131885: Use positional-only markers for ``max()`` and ``min()`` (python#131868)
  pythonGH-137426: Remove code deprecation of `importlib.abc.ResourceLoader` (pythonGH-137567)
  pythongh-125897: Mark range function parameters as positional only (python#125945)
  pythongh-137400: Fix a crash when disabling profiling across all threads (pythongh-137471)
  pythongh-115766: Fix IPv4Interface.is_unspecified (pythonGH-137326)
  pythongh-128813: cleanup C-API docs for PyComplexObject (pythonGH-137579)
  pythongh-135953: Profile a module or script with sampling profiler (python#136777)
  Fix documentation of hash in PyHash_FuncDef (python#137595)
encukou added a commit that referenced this pull request Aug 18, 2025
@encukou @JelleZijlstra
gh-135228: Create __dict__ and __weakref__ descriptors for object (GH… …
7dfa048 
…-136966)

This partially reverts #137047, keeping the tests for GC collectability of the
original class that dataclass adds `__slots__` to.
The reference leaks solved there are instead solved by having the `__dict__` &
`__weakref__` descriptors not tied to (and referencing) their class.

Instead, they're shared between all classes that need them (within
an interpreter).
The `__objclass__` ol the descriptors is set to `object`, since these
descriptors work with *any* object. (The appropriate checks were already
made in the get/set code, so the `__objclass__` check was redundant.)

The repr of these descriptors (and any others whose `__objclass__` is `object`)
now doesn't mention the objclass.

This change required adjustment of introspection code that checks
`__objclass__` to determine an object's “own” (i.e. not inherited) `__dict__`.
Third-party code that does similar introspection of the internals will also
need adjusting.


Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Agent-Hellboy pushed a commit to Agent-Hellboy/cpython that referenced this pull request Aug 19, 2025
@JelleZijlstra @ncoghlan
@encukou @serhiy-storchaka @Agent-Hellboy
pythongh-135228: When @DataClass(slots=True) replaces a dataclass, ma… …
5e78b22 
…ke the original class collectible (take 2) (pythonGH-137047)

Remove the `__dict__` and `__weakref__` descriptors from the original class when creating a dataclass from it.

An interesting hack, but more localized in scope than pythongh-135230.

This may be a breaking change if people intentionally keep the original class around
when using `@dataclass(slots=True)`, and then use `__dict__` or `__weakref__` on the
original class.


Co-authored-by: Alyssa Coghlan <ncoghlan@gmail.com>
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Agent-Hellboy pushed a commit to Agent-Hellboy/cpython that referenced this pull request Aug 19, 2025
@encukou @JelleZijlstra @Agent-Hellboy
pythongh-135228: Create __dict__ and __weakref__ descriptors for obje… …
a2ba4a5 
…ct (pythonGH-136966)

This partially reverts python#137047, keeping the tests for GC collectability of the
original class that dataclass adds `__slots__` to.
The reference leaks solved there are instead solved by having the `__dict__` &
`__weakref__` descriptors not tied to (and referencing) their class.

Instead, they're shared between all classes that need them (within
an interpreter).
The `__objclass__` ol the descriptors is set to `object`, since these
descriptors work with *any* object. (The appropriate checks were already
made in the get/set code, so the `__objclass__` check was redundant.)

The repr of these descriptors (and any others whose `__objclass__` is `object`)
now doesn't mention the objclass.

This change required adjustment of introspection code that checks
`__objclass__` to determine an object's “own” (i.e. not inherited) `__dict__`.
Third-party code that does similar introspection of the internals will also
need adjusting.


Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
kumaraditya303 pushed a commit to miss-islington/cpython that referenced this pull request Sep 9, 2025
@miss-islington @JelleZijlstra
@ncoghlan @encukou @serhiy-storchaka @kumaraditya303
[3.14] pythongh-135228: When @DataClass(slots=True) replaces a datacl… …
4bd33e9 
…ass, make the original class collectible (take 2) (pythonGH-137047) (python#137666)

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Alyssa Coghlan <ncoghlan@gmail.com>
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
gpshead added a commit to gpshead/cpython that referenced this pull request Apr 12, 2026
@gpshead @Prometheus3375 @claude
[3.13] pythongh-105936: Properly update closure cells for `__setattr_… …
aa1e00f 
…_` and `__delattr__` in frozen dataclasses with slots (pythonGH-144021)

pythongh-105936: Properly update closure cells for `__setattr__` and `__delattr__` in frozen dataclasses with slots (pythonGH-144021)
(cherry picked from commit 8a398bf)

The cherry-pick required additional changes beyond the original commit
because 3.13 lacks the `__class__` closure cell fixup machinery that
was added in 3.14 by pythonGH-124455 (pythongh-90562). Specifically:

- Backported `_update_func_cell_for__class__()` helper function and the
  closure fixup loop in `_add_slots()` from pythonGH-124455. Without these,
  renaming the closure variable from `cls` to `__class__` has no effect
  because nothing updates the cell when the class is recreated with slots.
- Changed `_add_slots()` to use `newcls` instead of reusing `cls` for the
  recreated class, so both old and new class references are available for
  the fixup loop.
- Replaced `assertNotHasAttr` with `assertFalse(hasattr(...))` in tests
  (assertNotHasAttr was added in 3.14).
- Dropped `test_original_class_is_gced` additions (that test does not
  exist on 3.13; it was added by pythonGH-137047 for pythongh-135228 which was not
  backported to 3.13).

Co-authored-by: Prometheus3375 <prometheus3375@gmail.com>
Co-authored-by: Sviataslau <35541026+Prometheus3375@users.noreply.github.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
@gpshead gpshead mentioned this pull request Apr 12, 2026
Merged
gpshead added a commit that referenced this pull request Apr 26, 2026
@gpshead @Prometheus3375
@JelleZijlstra @johnslavik
[3.13] gh-105936: Properly update closure cells for __setattr__ and _… …
9651429 
…_delattr__ in frozen dataclasses with slots (GH-144021) (GH-148476)

gh-105936: Properly update closure cells for `__setattr__` and `__delattr__` in frozen dataclasses with slots (GH-144021)
(cherry picked from commit 8a398bf)

The cherry-pick required additional changes beyond the original commit
because 3.13 lacks the `__class__` closure cell fixup machinery that
was added in 3.14 by GH-124455 (gh-90562). Specifically:

- Backported `_update_func_cell_for__class__()` helper function and the
  closure fixup loop in `_add_slots()` from GH-124455. Without these,
  renaming the closure variable from `cls` to `__class__` has no effect
  because nothing updates the cell when the class is recreated with slots.
- Changed `_add_slots()` to use `newcls` instead of reusing `cls` for the
  recreated class, so both old and new class references are available for
  the fixup loop.
- Replaced `assertNotHasAttr` with `assertFalse(hasattr(...))` in tests
  (assertNotHasAttr was added in 3.14).
- Dropped `test_original_class_is_gced` additions (that test does not
  exist on 3.13; it was added by GH-137047 for gh-135228 which was not
  backported to 3.13).

gh-148947: dataclasses: fix error on empty __class__ cell  (GH-148948)

Also add a test demonstrating the need for the existing "is oldcls" check.
(cherry picked from commit 6d7bbee)

---------

Co-authored-by: Prometheus3375 <prometheus3375@gmail.com>
Co-authored-by: Sviataslau <35541026+Prometheus3375@users.noreply.github.com>
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Bartosz Sławecki <bartosz@ilikepython.com>
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@JelleZijlstra @encukou @hugovk @bedevere-bot @serhiy-storchaka @brandtbucher