--- /dev/null
+error[E0277]: the trait bound `T: Foo` is not satisfied
+ --> $DIR/wf.rs:5:14
+ |
+LL | trait A<T: Foo> {}
+ | --- required by this bound in `A`
+LL | trait B<T> = A<T>;
+ | ^^^^ the trait `Foo` is not implemented for `T`
+ |
+help: consider restricting type parameter `T`
+ |
+LL | trait B<T: Foo> = A<T>;
+ | ^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.