error[E0433]: failed to resolve: you might be missing crate `clippy`
  --> $DIR/tool-mod-child.rs:2:5
   |
LL | use clippy::a::b;
   |     ^^^^^^ you might be missing crate `clippy`
   |
help: consider importing the `clippy` crate
   |
LL + extern crate clippy;
   |

error[E0432]: unresolved import `clippy`
  --> $DIR/tool-mod-child.rs:1:5
   |
LL | use clippy::a;
   |     ^^^^^^ you might be missing crate `clippy`
   |
help: consider importing the `clippy` crate
   |
LL + extern crate clippy;
   |

error[E0433]: failed to resolve: you might be missing crate `rustdoc`
  --> $DIR/tool-mod-child.rs:5:5
   |
LL | use rustdoc::a::b;
   |     ^^^^^^^ you might be missing crate `rustdoc`
   |
help: consider importing the `rustdoc` crate
   |
LL + extern crate rustdoc;
   |

error[E0432]: unresolved import `rustdoc`
  --> $DIR/tool-mod-child.rs:4:5
   |
LL | use rustdoc::a;
   |     ^^^^^^^ you might be missing crate `rustdoc`
   |
help: consider importing the `rustdoc` crate
   |
LL + extern crate rustdoc;
   |

error: aborting due to 4 previous errors

Some errors have detailed explanations: E0432, E0433.
For more information about an error, try `rustc --explain E0432`.