[vkuzo]

torchao removed the torchao/dtypes package (AffineQuantizedTensor and the Layout classes). This updates the transformers torchao integration to stop importing from torchao.dtypes so it no longer crashes against current torchao, mirroring the approach in transformers #45321.

Changes:

• integrations/torchao.py: drop the _quantization_type helper and its from torchao.dtypes import AffineQuantizedTensor isinstance branch; _linear_extra_repr now detects quantized weights inline via isinstance(self.weight, TorchAOBaseTensor) (from torchao.utils).
• tests/quantization/torchao_integration/test_torchao.py: replace the from torchao.dtypes import AffineQuantizedTensor import with from torchao.utils import TorchAOBaseTensor and update the isinstance assertions accordingly.
• docs/source/en/quantization/torchao.md: remove the MarlinSparseLayout ("int4-weight-only-24sparse") examples and migrate the Int4CPULayout example to Int4WeightOnlyConfig(int4_packing_format=PLAIN_INT32).

Test plan:

• python -c "import transformers.integrations.torchao" imports cleanly.

• RUN_SLOW=1 pytest tests/quantization/torchao_integration/test_torchao.py: all 18 TorchAOBaseTensor isinstance / FqnToConfig tests pass. The 3 remaining failures (test_int4wo_quant, test_int4wo_offload, test_serialization_accelerator_*_Int4WeightOnlyConfig) are pre-existing generation-output text comparisons pinned to torchao int4 kernel numerics on the test hardware, unrelated to this change.

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[github-actions]

[For maintainers] Suggested jobs to run (before merge)

run-slow: torchao_integration

[vkuzo]

cc @SunMarc , do you know who could help review/merge this?

context - making sure transformers follows the torchao deletion in pytorch/ao#4696

[github-actions]

---

CI recap

Dashboard: View test results in Grafana
Latest run: 30998997362:2
Result: success | Jobs: 16 | Tests: 173,174 | Failures: 0 | Duration: 13h 29m

[SunMarc]

Thanks a lot for this update ! I indeed saw a lot of breaking tests due to the latest version of torchao.

[SunMarc]

is this safe to import even with prior version of torchao ?

[vkuzo]

yes, that should work for torchao version 0.15+, which is what is supported by hf

[SunMarc]

thanks !

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