private static void reportWarnings(IntermediateGraph graph, ImportedModel model) {
        for (ImportedModel.Signature signature : model.signatures().values()) {
            for (String outputName : signature.outputs().values()) {
                reportWarnings(graph.get(outputName), model, new HashSet<>());
            }
        }
    }
Add any import warnings to the signature in the ImportedModel.
model-integration/src/main/java/ai/vespa/rankingexpression/importer/ModelImporter.java