error[E0277]: the trait bound `(): _Contains<&C>` is not satisfied --> $DIR/issue-85848.rs:24:5 | LL | writes_to_specific_path(&cap); | ^^^^^^^^^^^^^^^^^^^^^^^ the trait `_Contains<&C>` is not implemented for `()` | note: required because of the requirements on the impl of `Contains<(), true>` for `&C` --> $DIR/issue-85848.rs:21:12 | LL | impl Contains() }> for U where T: _Contains {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^ note: required because of the requirements on the impl of `Delegates<()>` for `&C` --> $DIR/issue-85848.rs:12:12 | LL | impl Delegates for T where T: Contains {} | ^^^^^^^^^^^^ ^ note: required by a bound in `writes_to_specific_path` --> $DIR/issue-85848.rs:29:31 | LL | fn writes_to_specific_path>(cap: &C) {} | ^^^^^^^^^^^^^ required by this bound in `writes_to_specific_path` error: unconstrained generic constant --> $DIR/issue-85848.rs:24:5 | LL | writes_to_specific_path(&cap); | ^^^^^^^^^^^^^^^^^^^^^^^ | = help: try adding a `where` bound using this expression: `where [(); { contains::() }]:` note: required because of the requirements on the impl of `Contains<(), true>` for `&C` --> $DIR/issue-85848.rs:21:12 | LL | impl Contains() }> for U where T: _Contains {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^ note: required because of the requirements on the impl of `Delegates<()>` for `&C` --> $DIR/issue-85848.rs:12:12 | LL | impl Delegates for T where T: Contains {} | ^^^^^^^^^^^^ ^ note: required by a bound in `writes_to_specific_path` --> $DIR/issue-85848.rs:29:31 | LL | fn writes_to_specific_path>(cap: &C) {} | ^^^^^^^^^^^^^ required by this bound in `writes_to_specific_path` error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0277`.