error[E0277]: the trait bound `Q: T3` is not satisfied
  --> $DIR/blame-trait-error.rs:28:46
   |
LL |     want(Wrapper { value: Burrito { filling: q } });
   |     ----                                     ^ the trait `T3` is not implemented for `Q`
   |     |
   |     required by a bound introduced by this call
   |
note: required for `Burrito<Q>` to implement `T2`
  --> $DIR/blame-trait-error.rs:11:13
   |
LL | impl<A: T3> T2 for Burrito<A> {}
   |         --  ^^     ^^^^^^^^^^
   |         |
   |         unsatisfied trait bound introduced here
note: required for `Wrapper<Burrito<Q>>` to implement `T1`
  --> $DIR/blame-trait-error.rs:6:13
   |
LL | impl<B: T2> T1 for Wrapper<B> {}
   |         --  ^^     ^^^^^^^^^^
   |         |
   |         unsatisfied trait bound introduced here
note: required by a bound in `want`
  --> $DIR/blame-trait-error.rs:25:12
   |
LL | fn want<V: T1>(_x: V) {}
   |            ^^ required by this bound in `want`
help: consider restricting type parameter `Q`
   |
LL | fn example<Q: T3>(q: Q) {
   |             ++++

error[E0277]: `()` is not an iterator
  --> $DIR/blame-trait-error.rs:31:15
   |
LL |     want(Some(()));
   |     ----      ^^ `()` is not an iterator
   |     |
   |     required by a bound introduced by this call
   |
   = help: the trait `Iterator` is not implemented for `()`
   = help: the trait `T1` is implemented for `Option<It>`
note: required for `Option<()>` to implement `T1`
  --> $DIR/blame-trait-error.rs:21:20
   |
LL | impl<It: Iterator> T1 for Option<It> {}
   |          --------  ^^     ^^^^^^^^^^
   |          |
   |          unsatisfied trait bound introduced here
note: required by a bound in `want`
  --> $DIR/blame-trait-error.rs:25:12
   |
LL | fn want<V: T1>(_x: V) {}
   |            ^^ required by this bound in `want`

error[E0277]: `Q` is not an iterator
  --> $DIR/blame-trait-error.rs:34:15
   |
LL |     want(Some(q));
   |     ----      ^ `Q` is not an iterator
   |     |
   |     required by a bound introduced by this call
   |
note: required for `Option<Q>` to implement `T1`
  --> $DIR/blame-trait-error.rs:21:20
   |
LL | impl<It: Iterator> T1 for Option<It> {}
   |          --------  ^^     ^^^^^^^^^^
   |          |
   |          unsatisfied trait bound introduced here
note: required by a bound in `want`
  --> $DIR/blame-trait-error.rs:25:12
   |
LL | fn want<V: T1>(_x: V) {}
   |            ^^ required by this bound in `want`
help: consider restricting type parameter `Q`
   |
LL | fn example<Q: std::iter::Iterator>(q: Q) {
   |             +++++++++++++++++++++

error[E0277]: `Q` is not an iterator
  --> $DIR/blame-trait-error.rs:37:16
   |
LL |     want(&Some(q));
   |     ----       ^ `Q` is not an iterator
   |     |
   |     required by a bound introduced by this call
   |
note: required for `Option<Q>` to implement `T1`
  --> $DIR/blame-trait-error.rs:21:20
   |
LL | impl<It: Iterator> T1 for Option<It> {}
   |          --------  ^^     ^^^^^^^^^^
   |          |
   |          unsatisfied trait bound introduced here
   = note: 1 redundant requirement hidden
   = note: required for `&Option<Q>` to implement `T1`
note: required by a bound in `want`
  --> $DIR/blame-trait-error.rs:25:12
   |
LL | fn want<V: T1>(_x: V) {}
   |            ^^ required by this bound in `want`
help: consider restricting type parameter `Q`
   |
LL | fn example<Q: std::iter::Iterator>(q: Q) {
   |             +++++++++++++++++++++

error: aborting due to 4 previous errors

For more information about this error, try `rustc --explain E0277`.