warning: argument must be of the form: `expected = "error message"`
  --> $DIR/test-should-panic-attr.rs:11:1
   |
LL | #[should_panic(expected)]
   | ^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: errors in this attribute were erroneously allowed and will become a hard error in a future release.

warning: argument must be of the form: `expected = "error message"`
  --> $DIR/test-should-panic-attr.rs:18:1
   |
LL | #[should_panic(expect)]
   | ^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: errors in this attribute were erroneously allowed and will become a hard error in a future release.

warning: argument must be of the form: `expected = "error message"`
  --> $DIR/test-should-panic-attr.rs:25:1
   |
LL | #[should_panic(expected(foo, bar))]
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: errors in this attribute were erroneously allowed and will become a hard error in a future release.

warning: argument must be of the form: `expected = "error message"`
  --> $DIR/test-should-panic-attr.rs:32:1
   |
LL | #[should_panic(expected = "foo", bar)]
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: errors in this attribute were erroneously allowed and will become a hard error in a future release.

warning: 4 warnings emitted