error[E0392]: parameter `T` is never used --> $DIR/issue-20413.rs:6:15 | LL | struct NoData; | ^ unused parameter | = help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData` = help: if you intended `T` to be a const parameter, use `const T: usize` instead error[E0275]: overflow evaluating the requirement `NoData>>>>>>: Foo` --> $DIR/issue-20413.rs:9:36 | LL | impl Foo for T where NoData: Foo { | ^^^ | = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_20413`) note: required for `NoData>>>>>>>>>>>>` to implement `Foo` --> $DIR/issue-20413.rs:9:9 | LL | impl Foo for T where NoData: Foo { | ^^^ ^ --- unsatisfied trait bound introduced here = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' = note: 127 redundant requirements hidden = note: required for `NoData` to implement `Foo` error[E0275]: overflow evaluating the requirement `EvenLessData>>>>>>: Baz` --> $DIR/issue-20413.rs:28:42 | LL | impl Bar for T where EvenLessData: Baz { | ^^^ | = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_20413`) note: required for `AlmostNoData>>>>>>` to implement `Bar` --> $DIR/issue-20413.rs:28:9 | LL | impl Bar for T where EvenLessData: Baz { | ^^^ ^ --- unsatisfied trait bound introduced here = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' note: required for `EvenLessData>>>>>>` to implement `Baz` --> $DIR/issue-20413.rs:35:9 | LL | impl Baz for T where AlmostNoData: Bar { | ^^^ ^ --- unsatisfied trait bound introduced here = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' = note: 126 redundant requirements hidden = note: required for `EvenLessData` to implement `Baz` error[E0275]: overflow evaluating the requirement `AlmostNoData>>>>>>: Bar` --> $DIR/issue-20413.rs:35:42 | LL | impl Baz for T where AlmostNoData: Bar { | ^^^ | = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_20413`) note: required for `EvenLessData>>>>>>` to implement `Baz` --> $DIR/issue-20413.rs:35:9 | LL | impl Baz for T where AlmostNoData: Bar { | ^^^ ^ --- unsatisfied trait bound introduced here = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' note: required for `AlmostNoData>>>>>>` to implement `Bar` --> $DIR/issue-20413.rs:28:9 | LL | impl Bar for T where EvenLessData: Baz { | ^^^ ^ --- unsatisfied trait bound introduced here = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt' = note: 126 redundant requirements hidden = note: required for `AlmostNoData` to implement `Bar` error: aborting due to 4 previous errors Some errors have detailed explanations: E0275, E0392. For more information about an error, try `rustc --explain E0275`.