Fix bug in while shapes (#1479)

Signed-off-by: Tom Wildenhain <[email protected]>

Author: TomWildenhain-Microsoft

tf2onnx/onnx_opset/controlflow.py

@@ -510,9 +510,8 @@ def wire_while_body(parent_g, g, loop_node, body_input_to_state_var, cond_input_
     g.set_dtype(func_inputs[0], onnx_pb.TensorProto.INT64)
     g.inputs = [g.get_node_by_output(inp) for inp in func_inputs]
 
-    for p, c in zip(loop_node.inputs, func_inputs):
-        shape = p.output_shapes[0]
-        g.set_shape(c, shape)
+    for p, c in zip(loop_node.input, func_inputs):
+        g.copy_shape(p, c)
 
     for i, node in enumerate(g.inputs):
         if node.output[0] not in func_inputs: