error[E0433]: failed to resolve: use of unresolved module or unlinked crate `assert_mem_uninitialized_valid` --> tests/fail/rustc-error2.rs:LL:CC | LL | fn deref(&self) -> &assert_mem_uninitialized_valid::Target { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ use of unresolved module or unlinked crate `assert_mem_uninitialized_valid` | = help: you might be missing a crate named `assert_mem_uninitialized_valid` error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0433`.