error: doc alias attribute expects a string: #[doc(alias = "0")]
  --> $DIR/check-doc-alias-attr.rs:7:7
   |
LL | #[doc(alias)]
   |       ^^^^^

error: doc alias attribute expects a string: #[doc(alias = "0")]
  --> $DIR/check-doc-alias-attr.rs:8:7
   |
LL | #[doc(alias = 0)]
   |       ^^^^^^^^^

error: doc alias attribute expects a string: #[doc(alias = "0")]
  --> $DIR/check-doc-alias-attr.rs:9:7
   |
LL | #[doc(alias("bar"))]
   |       ^^^^^^^^^^^^

error: '\"' character isn't allowed in `#[doc(alias = "...")]`
  --> $DIR/check-doc-alias-attr.rs:10:7
   |
LL | #[doc(alias = "\"")]
   |       ^^^^^^^^^^^^

error: '\n' character isn't allowed in `#[doc(alias = "...")]`
  --> $DIR/check-doc-alias-attr.rs:11:7
   |
LL | #[doc(alias = "\n")]
   |       ^^^^^^^^^^^^

error: '\n' character isn't allowed in `#[doc(alias = "...")]`
  --> $DIR/check-doc-alias-attr.rs:12:7
   |
LL |   #[doc(alias = "
   |  _______^
LL | | ")]
   | |_^

error: '\t' character isn't allowed in `#[doc(alias = "...")]`
  --> $DIR/check-doc-alias-attr.rs:14:7
   |
LL | #[doc(alias = "\t")]
   |       ^^^^^^^^^^^^

error: `#[doc(alias = "...")]` cannot start or end with ' '
  --> $DIR/check-doc-alias-attr.rs:15:7
   |
LL | #[doc(alias = " hello")]
   |       ^^^^^^^^^^^^^^^^

error: `#[doc(alias = "...")]` cannot start or end with ' '
  --> $DIR/check-doc-alias-attr.rs:16:7
   |
LL | #[doc(alias = "hello ")]
   |       ^^^^^^^^^^^^^^^^

error: aborting due to 9 previous errors