Added support for catching UserWarnings emitted by FINN during onnx execution as errors.

tests/transformation/test_qonnx_to_finn.py

@@ -35,6 +35,7 @@ import brevitas.onnx as bo
 import numpy as np
 import onnx
 import onnx.numpy_helper as nph
+import warnings
 from brevitas.export.onnx.generic.manager import BrevitasONNXManager
 from pkgutil import get_data
 from qonnx.util.cleanup import cleanup
@@ -140,13 +141,22 @@ def test_QONNX_to_FINN(model_name, wbits, abits):
     # Compare output
     model = ModelWrapper(qonnx_base_path.format("whole_trafo"))
     input_dict = {model.graph.input[0].name: input_tensor}
-    output_dict = oxe.execute_onnx(model, input_dict, False)
-    test_output = output_dict[model.graph.output[0].name]
-
-    assert np.isclose(test_output, finn_export_output).all(), (
-        "The output of the FINN model "
-        "and the QONNX -> FINN converted model should match."
-    )
+    with warnings.catch_warnings(record=True) as warn_list:
+        warnings.simplefilter("always")
+        output_dict = oxe.execute_onnx(model, input_dict, False)
+        test_output = output_dict[model.graph.output[0].name]
+        assert np.isclose(test_output, finn_export_output).all(), (
+            "The output of the FINN model "
+            "and the QONNX -> FINN converted model should match."
+        )
+        # Check for UserWarnings
+        for warn in warn_list:
+            if issubclass(warn.category, UserWarning):
+                raise RuntimeError(
+                    "Treating the following warning as an error, "
+                    "since the warning is potentially unfixable for the user: "
+                    + str(warn)
+                )
 
     # Run analysis passes on the converted model
     model = ModelWrapper(qonnx_base_path.format("whole_trafo"))