POTENTIAL DEADLOCK: Inconsistent locking. saw this ordering in one goroutine:
happened before
bit_array.go:355 common.(*BitArray).Update { bA.mtx.Lock() } <<<<<
bit_array_test.go:198 common.TestUpdateNeverPanics { a.Update(b) }

happened after
bit_array.go:356 common.(*BitArray).Update { o.mtx.Lock() } <<<<<
bit_array_test.go:198 common.TestUpdateNeverPanics { a.Update(b) }

in another goroutine: happened before
bit_array.go:355 common.(*BitArray).Update { bA.mtx.Lock() } <<<<<
bit_array_test.go:199 common.TestUpdateNeverPanics { b.Update(a) }

happened after
bit_array.go:356 common.(*BitArray).Update { o.mtx.Lock() } <<<<<
bit_array_test.go:199 common.TestUpdateNeverPanics { b.Update(a) }

Other goroutines holding locks:
goroutine 100745 lock 0xc0022a4db0
bit_array.go:355 common.(*BitArray).Update { bA.mtx.Lock() } <<<<<
bit_array_test.go:199 common.TestUpdateNeverPanics { b.Update(a) }