execR,
  execW
< execRInternal;

testR,
  testW
< testRInternal;
`

// cyclicRanks lists lock ranks that allow multiple locks of the same
// rank to be acquired simultaneously. The runtime enforces ordering
// within these ranks using a separate mechanism.
var cyclicRanks = map[string]bool{
	// Multiple timers are locked simultaneously in destroy().
	"timers": true,