Rust 1.16.0 ? Operator Issue On Result

main.rs

use std::io;
use std::io::prelude::*;
use std::fs::File;

// error[E0277]: the trait bound `(): std::ops::Carrier` is not satisfied
//   --> src/main.rs:43:17
//    |
// 43 |     let mut f = File::open("foo.txt")?;
//    |                 ----------------------
//    |                 |
//    |                 the trait `std::ops::Carrier` is not implemented for `()`
//    |                 in this macro invocation
//    |
//    = note: required by `std::ops::Carrier::from_error`

// error[E0277]: the trait bound `(): std::ops::Carrier` is not satisfied
//   --> src/main.rs:47:5
//    |
// 47 |     f.read(&mut buffer)?;
//    |     --------------------
//    |     |
//    |     the trait `std::ops::Carrier` is not implemented for `()`
//    |     in this macro invocation
//    |
//    = note: required by `std::ops::Carrier::from_error`
fn main(){
  let mut f = File::open("foo.txt")?;
  let mut buffer = [0; 10];

  // read up to 10 bytes
  f.read(&mut buffer)?;

  println!("The bytes: {:?}", buffer);
}