continue
				}

				select {
				case ft.errors <- err:
					// nothing to do

				case ft := <-wk.retireTrackerCh:
					retireTracker(ft)

				case <-wk.terminateCh:
					return
				}
			}

		case ft := <-wk.retireTrackerCh:
			retireTracker(ft)

		case <-wk.terminateCh:
			return
		}
	}
}

// used only by the worker goroutine