error: expected one of `(`, `,`, `::`, or `=`, found `-`
  --> $DIR/attr-incomplete.rs:1:13
   |
LL | #[cfg(target-os = "windows")]
   |             ^ expected one of `(`, `,`, `::`, or `=`

error: expected a literal (`1u8`, `1.0f32`, `"string"`, etc.) here, found `%`
  --> $DIR/attr-incomplete.rs:5:19
   |
LL | #[cfg(target_os = %)]
   |                   ^

error: expected one of `(`, `,`, `::`, or `=`, found `?`
  --> $DIR/attr-incomplete.rs:9:16
   |
LL | #[cfg(target_os?)]
   |                ^ expected one of `(`, `,`, `::`, or `=`

error: wrong meta list delimiters
  --> $DIR/attr-incomplete.rs:13:6
   |
LL | #[cfg[target_os]]
   |      ^^^^^^^^^^^
   |
help: the delimiters should be `(` and `)`
   |
LL - #[cfg[target_os]]
LL + #[cfg(target_os)]
   |

error: aborting due to 4 previous errors