diff --git a/egs/librispeech/ASR/pruned_transducer_stateless7/scaling.py b/egs/librispeech/ASR/pruned_transducer_stateless7/scaling.py
index a2200c04b..4ea5e0558 100644
--- a/egs/librispeech/ASR/pruned_transducer_stateless7/scaling.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless7/scaling.py
@@ -201,7 +201,6 @@ def random_cast_to_half(x: Tensor,
     """
     if x.dtype == torch.float16:
         return x
-    x_sign = x.sign()
     x_abs = x.abs()
     is_too_small = (x_abs < min_abs)
     # for elements where is_too_small is true, random_val will contain +-min_abs with
@@ -223,7 +222,6 @@ class RandomGradFunction(torch.autograd.Function):
 
     @staticmethod
     def backward(ctx, ans_grad: Tensor) -> Tuple[Tensor, None]:
-        min_abs = ctx.min_abs
         if ans_grad.dtype == torch.float16:
             return random_cast_to_half(ans_grad.to(torch.float32),
                                        min_abs=ctx.min_abs), None