Warning 'The attention mask is not set'

[AlessandroSpallina]

Having the same warning appearing in a closed pull request #33509

System Info

• transformers version: 4.47.1
• Platform: Linux-5.15.146.1-microsoft-standard-WSL2-x86_64-with-glibc2.39
• Python version: 3.12.3
• Huggingface_hub version: 0.27.0
• Safetensors version: 0.5.0
• Accelerate version: 1.2.1
• Accelerate config: not found
• PyTorch version (GPU?): 2.5.1+cu124 (True)
• Tensorflow version (GPU?): not installed (NA)
• Flax version (CPU?/GPU?/TPU?): not installed (NA)
• Jax version: not installed
• JaxLib version: not installed
• Using distributed or parallel set-up in script?: no
• Using GPU in script?: yes
• GPU type: NVIDIA RTX 4000 Ada Generation Laptop GPU

Who can help?

@ylacombe

Information

• The official example scripts
• My own modified scripts

Tasks

• An officially supported task in the examples folder (such as GLUE/SQuAD, ...)
• My own task or dataset (give details below)

Reproduction

code:

        pipe = pipeline(
            "automatic-speech-recognition",
            model=self.model,
            torch_dtype=torch.float16,
            chunk_length_s=30,
            batch_size=24,
            return_timestamps=True,
            device=self.device,
            tokenizer=processor.tokenizer,
            feature_extractor=processor.feature_extractor,
            model_kwargs={"use_flash_attention_2": True},
            generate_kwargs={
                "max_new_tokens": 128,
            },
        )

warning:

The attention mask is not set and cannot be inferred from input because pad token is same as eos token. As a consequence, you may observe unexpected behavior. Please pass your input's `attention_mask` to obtain reliable results.
Whisper did not predict an ending timestamp, which can happen if audio is cut off in the middle of a word. Also make sure WhisperTimeStampLogitsProcessor was used during generation.

Expected behavior

No warning