[jameshilliard]

Summary of changes

Wheel tags and limited-API validation currently combine sysconfig values with information from the running interpreter. When cross-compiling, this can produce host-specific tags or reject stable-ABI wheels supported by the target.

Use sysconfig data for the Python version, implementation, pointer size and debug status, retaining best-effort fallbacks when configuration data is unavailable. Fall back to SOABI when VERSION is missing or invalid, and use EXT_SUFFIX for Windows debug builds when Py_DEBUG is unavailable.

Validate wheel tags against the configured interpreter's version and ABI instead of tags.sys_tags(), preserving platform overrides and compressed ABI3/ABI3T tags. Add regression coverage for differing host and target configurations, missing metadata, and native limited-API wheels, including --skip-build and importing the extension. Also add Python 3.15t to CI.

Follow-up to #5193 and #5352.

Closes #5360

Testing

• Wheel, extension, wheel installation, metadata, build-backend and editable-install regression tests on CPython 3.14: 503 passed.
• Focused test_bdist_wheel.py and test_build_ext.py tests on CPython 3.14 and 3.15t: 188 passed each; CPython 3.14t and PyPy 3.11: 186 passed and 2 skipped each.
• Ruff, formatting, mypy and whitespace checks passed.

Pull Request Checklist

• Changes have tests
• News fragment added in newsfragments/.
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[jaraco]

I'm working in jaraco/skeleton#224 to add 3.15t to the build matrix (for skeleton projects).

[jaraco]

One nit, not a blocker: after this change _python_version() describes the target everywhere except dist_files, which still records the host version:

setuptools/setuptools/command/bdist_wheel.py

Lines 527 to 532 in 2382f7e

	# Add to 'Distribution.dist_files' so that the "upload" command works
	getattr(self.distribution, "dist_files", []).append((
	"bdist_wheel",
	f"{sys.version_info.major}.{sys.version_info.minor}",
	wheel_path,
	))

When cross-compiling, that entry gets the building interpreter's version rather than the configured target's, which is inconsistent with the rest of the PR. ".".join(map(str, _python_version())) would keep it aligned. Fine by me to leave it for a follow-up if you'd rather keep this diff tight.

[jameshilliard]

When cross-compiling, that entry gets the building interpreter's version rather than the configured target's, which is inconsistent with the rest of the PR. ".".join(map(str, _python_version())) would keep it aligned. Fine by me to leave it for a follow-up if you'd rather keep this diff tight.

Should be fixed now.