suspend fun main() = runBlocking {
    log(1)
    val job = launch(Dispatchers.Unconfined) {
        log(2)
        val job2 = launch(Dispatchers.Default) {
            log(3)
            val x = 1 / 0
            log(4)
        }
        job2.join()
        log(5)
    }
    log(6)
    job.join()
    log(7)
}

val dateFormat = SimpleDateFormat("HH:mm:ss:SSS")

val now = {
    dateFormat.format(Date(System.currentTimeMillis()))
}

fun log(msg: Any?) = println("${now()} [${Thread.currentThread().name}] $msg")

public final override suspend fun join() {
    if (!joinInternal()) { // fast-path no wait
        coroutineContext.checkCompletion()
        return // do not suspend
    }
    return joinSuspend() // slow-path wait
}

public suspend inline fun <T> suspendCancellableCoroutine(
    crossinline block: (CancellableContinuation<T>) -> Unit
): T =
    suspendCoroutineUninterceptedOrReturn { uCont ->
        val cancellable = CancellableContinuationImpl(uCont.intercepted(), resumeMode = MODE_CANCELLABLE)
        // NOTE: Before version 1.1.0 the following invocation was inlined here, so invocation of this
        // method indicates that the code was compiled by kotlinx.coroutines < 1.1.0
        // cancellable.initCancellability()
        block(cancellable)
        cancellable.getResult() // HERE!!!!!
    }

private suspend fun joinSuspend() = suspendCancellableCoroutine<Unit> { cont ->
    // We have to invoke join() handler only on cancellation, on completion we will be resumed regularly without handlers
    cont.disposeOnCancellation(invokeOnCompletion(handler = ResumeOnCompletion(this, cont).asHandler))
}