torch-abi-audit

Audit Python extension modules for compliance with the PyTorch Stable ABI (aoti_torch_* C shim and torch::stable::* / torch::headeronly::* C++ wrappers, introduced in PyTorch 2.9). Walks every .so shipped in a package — both Python extension modules and bundled internal libraries — and reports which stick to the stable surface and which reach into at:: / c10:: / torch::jit:: internals.

As a side benefit the same symbol-table walk also reports CPython Stable ABI (PEP 384) compliance, since the data is right there.

📖 Documentation: https://quansight.github.io/torch-abi-audit/

Install

pip install torch-abi-audit

Linux and macOS only for now (Windows requires dumpbin support — not yet implemented).

CLI usage

# Inspect an installed PyTorch ecosystem package by import name
torch-abi-audit torchaudio

# Inspect a path to an installed package or a single .so
torch-abi-audit /path/to/site-packages/somepkg

# Inspect every package in the current environment's site-packages
torch-abi-audit --env

# Inspect a specific site-packages directory
torch-abi-audit --site-packages /opt/venv/lib/python3.12/site-packages

# JSON output for tooling
torch-abi-audit --env --json | jq '.packages[] | select(.torch.uses_torch)'

Example output

Run against the three packages tracked by scripts/check_real_world.py (captured against torch 2.11.0 / torchaudio 2.11.0 / torchcodec 0.11.1):

Package: torchaudio
  Root: <venv>/lib/python3.11/site-packages/torchaudio
  Torch ABI:   STABLE
  CPython ABI: n/a
  Extensions:  0
  Bundled libs: 3
  -- bundled libs --
    [STABLE  ] [abi3-tagged-no-capi   ] lib/_torchaudio.abi3.so  (stable_shim=6, unstable=0)
    [STABLE  ] [abi3-tagged-no-capi   ] lib/libtorchaudio.abi3.so  (stable_shim=80, unstable=0)
    [STABLE  ] [abi3-tagged-no-capi   ] lib/torchaudio_prefixctc.abi3.so  (stable_shim=62, unstable=0)

Package: torch
  Root: <venv>/lib/python3.11/site-packages/torch
  Torch ABI:   UNSTABLE
  CPython ABI: no
  Extensions:  1
  Bundled libs: 13
  -- extensions --
    [NO-TORCH] [not-abi3              ] _C.cpython-311-aarch64-linux-gnu.so
  -- bundled libs --
    [UNSTABLE] [not-abi3              ] lib/libc10_cuda.so  (stable_shim=0, unstable=44)
    [UNSTABLE] [not-abi3              ] lib/libtorch_cpu.so  (stable_shim=0, unstable=327)
    [UNSTABLE] [not-abi3              ] lib/libtorch_cuda.so  (stable_shim=0, unstable=2515)
    [UNSTABLE] [uses-private-api      ] lib/libtorch_python.so  (stable_shim=0, unstable=5085)
    ... (9 more, mostly NO-TORCH or UNSTABLE)

Package: torchcodec
  Root: <venv>/lib/python3.11/site-packages/torchcodec
  Torch ABI:   UNSTABLE
  CPython ABI: no
  Extensions:  5
  Bundled libs: 10
  -- extensions --
    [NO-TORCH] [uses-private-api      ] libtorchcodec_pybind_ops4.so
    ... (4 similar)
  -- bundled libs --
    [UNSTABLE] [not-abi3              ] libtorchcodec_core4.so  (stable_shim=64, unstable=4)
    ... (4 similar)
    [STABLE  ] [uses-private-api      ] libtorchcodec_custom_ops4.so  (stable_shim=68, unstable=0)
    ... (4 similar)

torchaudio is reported as stable because every compiled library it ships links against aoti_torch_* and torch::stable::* only. torch lands on UNSTABLE because its bundled libtorch_python.so, libtorch_cpu.so, etc. naturally reference internal at:: / c10:: namespaces (torch implements those internals, after all). torchcodec is mid-migration: the custom_ops* libs already use the stable surface, but core* libs still link a handful of c10:: symbols.

Python API

from torch_abi_audit import (
    inspect_extension,
    inspect_package,
    inspect_site_packages,
)

report = inspect_package("torchaudio")
print(report.torch_verdict)             # "torch-stable" | "torch-unstable" | "no-torch"

# `extensions` holds Python extension modules; `bundled_libs` holds the
# rest of the compiled .so files (libtorch_python.so, STABLE_TORCH_LIBRARY
# plugins, etc.). Both contribute to the verdict.
for lib in (*report.extensions, *report.bundled_libs):
    print(lib.path, lib.torch.stable, lib.cpython.compliant)

Development

uv sync                          # install + dev dependencies in .venv
uv run pytest                    # run tests
uv run pyrefly check             # type-check
uv run zensical serve docs/      # local docs server

License

MIT — see LICENSE.