Incorrect error when pattern type doesn't match expression type

[siddharth-krishna]

match (1.2, 3.0, 3.0) with {
  | (x, y, z) -> 3
  | (x, y, (_, _)) -> 2
  | _ -> 9
}

The error should be on line 3 and should say something like ... but instead found (double, double, ('a, 'b)).