fix #1692

transformers/modeling_tf_xlnet.py

@@ -539,7 +539,7 @@ class TFXLNetMainLayer(tf.keras.layers.Layer):
         assert input_mask is None or attention_mask is None, "You can only use one of input_mask (uses 1 for padding) " \
             "or attention_mask (uses 0 for padding, added for compatbility with BERT). Please choose one."
         if input_mask is None and attention_mask is not None:
-            input_mask = 1.0 - attention_mask
+            input_mask = 1.0 - tf.cast(attention_mask, dtype=dtype_float)
         if input_mask is not None and perm_mask is not None:
             data_mask = input_mask[None] + perm_mask
         elif input_mask is not None and perm_mask is None: