build: add support for python 3.14

[CandiedCode]

Summary

Fixes #16750

While scanning my docker images for CVE's there are several that are being found due to python 3.13

NAME                INSTALLED                     FIXED IN     TYPE    VULNERABILITY        SEVERITY    EPSS           RISK 
python              3.13.13                                    binary  CVE-2025-12781       Medium      < 0.1% (4th)   < 0.1  
python              3.13.13                                    binary  CVE-2026-1502        Medium      < 0.1% (18th)  < 0.1  
python              3.13.13                                    binary  CVE-2026-3298        High        < 0.1% (20th)  < 0.1  
python              3.13.13                                    binary  CVE-2026-4786        High        < 0.1% (5th)   < 0.1  
python              3.13.13                                    binary  CVE-2026-6019        Low         < 0.1% (15th)  < 0.1  
python              3.13.13                                    binary  CVE-2026-6100        Critical    0.2% (35th)    0.1    

Pytorch and vllm support python 3.14, but I'm unable to upgrade until Executorch supports 3.14 as well.

Test plan

I added 3.14 to CI for it to run all the tests

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/19254

• 📄 Preview Python docs built from this PR

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⚠️ 13 Awaiting Approval, 1 Unrelated Failure

As of commit f0f1bb7 with merge base 3be4546 ():

AWAITING APPROVAL - The following workflows need approval before CI can run:

• Build documentation (gh)
• Build Presets (gh)
• Cadence Build & Test (gh)
• Lint (gh)
• periodic (gh)
• pull (gh)
• Test ARM Backend (gh)
• Test CoreML Backend (gh)
• Test QNN Backend (gh)
• Test Vulkan Backend (gh)
• Test XNNPACK Backend (gh)
• trunk (gh)
• Windows MSVC Build (gh)

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• Copilot code review / Cleanup artifacts (gh) (detected as infra flaky with no log or failing log classifier)

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[github-actions]

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[Copilot]

Pull request overview

This PR updates ExecuTorch’s packaging metadata, documentation, and CI matrices to recognize/support Python 3.14 (issue #16750), primarily by widening the declared supported Python range and running CI/wheel builds against 3.14.

Changes:

• Expand supported Python range in packaging metadata (requires-python, classifiers) and formatting config (Black target versions).
• Update multiple docs/READMEs to advertise Python 3.14 support.
• Add Python 3.14 to GitHub Actions test and wheel build matrices.

Reviewed changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
pyproject.toml	Add Python 3.14 classifier; widen requires-python to <3.15; include py314 for Black.
docs/source/using-executorch-building-from-source.md	Update documented supported Python range to 3.10–3.14.
docs/source/raspberry_pi_llama_tutorial.md	Update prerequisite Python range and version-check guidance to 3.10–3.14.
docs/source/quick-start-section.md	Update prerequisite Python range to 3.10–3.14.
docs/source/pathway-quickstart.md	Update virtualenv Python range guidance to 3.10–3.14.
docs/source/pathway-beginner.md	Update prerequisites to 3.10–3.14.
docs/source/getting-started.md	Update system requirements to 3.10–3.14.
README-wheel.md	Update supported Python versions list to include 3.14.
.github/workflows/pull.yml	Add 3.14 to the test-qnn-wheel-packages-linux matrix.
.github/workflows/build-wheels-windows.yml	Add 3.14 to wheel build matrix.
.github/workflows/build-wheels-macos.yml	Add 3.14 to wheel build matrix.
.github/workflows/build-wheels-linux.yml	Add 3.14 to wheel build matrix.
.github/workflows/build-wheels-aarch64-linux.yml	Add 3.14 to wheel build matrix.
.claude/skills/building/SKILL.md	Update Python version guidance to include 3.14.
.ci/scripts/test_coreml_bc.sh	Update comment about Python compatibility for backward-compat CoreML test script.

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[Copilot]

The QNN wheel test job now runs on Python 3.14, but the repo’s QNN backend rules document that Python 3.13+ (NumPy 2.x) is incompatible with the PyQnnManagerAdaptor pybind11 layer and breaks QNN compilation. Unless that constraint has been lifted, consider excluding 3.14 from this QNN-specific matrix (or pinning the job to Python 3.12 + numpy<2.0 / updating the QNN pybind layer) so CI doesn’t add a known-failing configuration.

Suggested change

	python-version: [ "3.10", "3.11", "3.12", "3.13", "3.14" ]
	python-version: [ "3.10", "3.11", "3.12" ]

[Copilot]

This note is internally inconsistent now: it says Python 3.10–3.14 is compatible, but then implies Homebrew Python 3.14+ is incompatible and suggests installing 3.12. Please update the example to match the supported range (e.g., only suggest installing an older Python if the user has 3.15+), so readers aren’t told to downgrade unnecessarily.