error[E0710]: an unknown tool name found in scoped lint: `foo::bar`
  --> $DIR/tool_lints.rs:1:8
   |
LL | #[warn(foo::bar)]
   |        ^^^

error[E0710]: an unknown tool name found in scoped lint: `foo::bar`
  --> $DIR/tool_lints.rs:1:8
   |
LL | #[warn(foo::bar)]
   |        ^^^

error[E0710]: an unknown tool name found in scoped lint: `foo::bar`
  --> $DIR/tool_lints.rs:1:8
   |
LL | #[warn(foo::bar)]
   |        ^^^

error: aborting due to 3 previous errors

For more information about this error, try `rustc --explain E0710`.