This error occurs when the ONNX converter is unable to find a corresponding symbolic function to convert a “call_function” node in the input graph to its equivalence in ONNX. The “call_function” node represents a normalized function call in PyTorch, such as “torch.aten.ops.add”.

To resolve this error, you can try one of the following:

  • If exists, apply the auto-fix suggested by the diagnostic. TODO: this part is not available yet.

  • Rewrite the model using only supported PyTorch operators or functions.

  • Follow this guide to write and register a custom symbolic function for the unsupported call_function FX node.


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