error[E0391]: cycle detected when computing the supertraits of `B`
  --> $DIR/cycle-trait-supertrait-indirect.rs:17:1
   |
LL | trait B: C {
   | ^^^^^^^^^^
   |
note: ...which requires computing the supertraits of `C`...
  --> $DIR/cycle-trait-supertrait-indirect.rs:21:1
   |
LL | trait C: B { }
   | ^^^^^^^^^^
   = note: ...which again requires computing the supertraits of `B`, completing the cycle
note: cycle used when computing the supertraits of `A`
  --> $DIR/cycle-trait-supertrait-indirect.rs:14:1
   |
LL | trait A: B {
   | ^^^^^^^^^^

error: aborting due to previous error

For more information about this error, try `rustc --explain E0391`.