Create a release branch ABI stability regression test

[gpshead]

BPO	43725
Nosy	@gpshead, @vstinner, @tiran, @ned-deily, @encukou, @ambv, @zooba, @pablogsal
PRs	bpo-43725: Add CI step to check changes in the exported ABI #25188 [3.9] bpo-43725: Add CI step to check changes in the exported ABI #25230 [3.8] bpo-43725: Add CI step to check changes in the exported ABI #25232 [3.8] bpo-43725: Add ignore file for the abidump check #25322 [3.9] bpo-43725: Add ignore file for the abidump check #25323 [3.9] Revert "[3.9] bpo-43725: Add ignore file for the abidump check" #25394
Files	compat_report.html

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

Show more details

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2021-04-04.04:35:13.558>
labels = ['build', '3.8', '3.9', 'expert-C-API', 'type-feature', 'tests', 'interpreter-core', '3.10']
title = 'Create a release branch ABI stability regression test'
updated_at = <Date 2021-10-15.14:16:28.469>
user = 'https://github.com/gpshead'

bugs.python.org fields:

activity = <Date 2021-10-15.14:16:28.469>
actor = 'pablogsal'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Build', 'Interpreter Core', 'Tests', 'C API']
creation = <Date 2021-04-04.04:35:13.558>
creator = 'gregory.p.smith'
dependencies = []
files = ['49935']
hgrepos = []
issue_num = 43725
keywords = ['patch']
message_count = 36.0
messages = ['390173', '390184', '390203', '390205', '390207', '390208', '390213', '390214', '390310', '390311', '390312', '390313', '390315', '390316', '390319', '390325', '390372', '390374', '390382', '390660', '390668', '390670', '390985', '390986', '390987', '390994', '391007', '391008', '391009', '391010', '391011', '392205', '392207', '392208', '404019', '404022']
nosy_count = 8.0
nosy_names = ['gregory.p.smith', 'vstinner', 'christian.heimes', 'ned.deily', 'petr.viktorin', 'lukasz.langa', 'steve.dower', 'pablogsal']
pr_nums = ['25188', '25230', '25232', '25322', '25323', '25394']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue43725'
versions = ['Python 3.8', 'Python 3.9', 'Python 3.10']

Linked PRs

• [3.12] gh-87891: Add ABI check to CI #104793

[gpshead]

In order to automate prevention of ABI regressions in stable releases, we could create an automated ABI stability test generator and check the specific ABI test it generates into each specific release branch.

I'm envisioning the main branch only having a code generator that creates such a test, and the release branches only having the output of that as Lib/tests/release_X_Y_ABI_stability_test.py and a policy of never updating that within a release branch without *extreme* attention to detail.

Such updates wouldn't happen by default in our current workflow as they're unique and versioned in every release branch so automated backport PRs wouldn't touch them - leaving CI to run them and highlight failures on attempted backports to do inadvertently cause an ABI shift.