error: handle written amount returned or use `Write::write_all` instead
  --> $DIR/unused_io_amount.rs:11:5
   |
11 |     try!(s.write(b"test"));
   |     ^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: `-D unused-io-amount` implied by `-D warnings`
   = note: this error originates in a macro outside of the current crate (run with -Z external-macro-backtrace for more info)

error: handle read amount returned or use `Read::read_exact` instead
  --> $DIR/unused_io_amount.rs:13:5
   |
13 |     try!(s.read(&mut buf));
   |     ^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: this error originates in a macro outside of the current crate (run with -Z external-macro-backtrace for more info)

error: handle written amount returned or use `Write::write_all` instead
  --> $DIR/unused_io_amount.rs:18:5
   |
18 |     s.write(b"test")?;
   |     ^^^^^^^^^^^^^^^^^

error: handle read amount returned or use `Read::read_exact` instead
  --> $DIR/unused_io_amount.rs:20:5
   |
20 |     s.read(&mut buf)?;
   |     ^^^^^^^^^^^^^^^^^

error: handle written amount returned or use `Write::write_all` instead
  --> $DIR/unused_io_amount.rs:25:5
   |
25 |     s.write(b"test").unwrap();
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^

error: handle read amount returned or use `Read::read_exact` instead
  --> $DIR/unused_io_amount.rs:27:5
   |
27 |     s.read(&mut buf).unwrap();
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^