iOS12 bug, API cannot callback normal!

[Cellphoness]

mac environment, simulator ios12, when I shortdown the WIFI, Reachability calback NotReachable.
then i connect to WIFI, Reachability cannot callback any more!
I set breakpoint in Reachability.m to monior
`static void ReachabilityCallback(SCNetworkReachabilityRef target, SCNetworkReachabilityFlags flags, void* info)
{
#pragma unused (target, flags)
NSCAssert(info != NULL, @"info was NULL in ReachabilityCallback");
NSCAssert([(__bridge NSObject*) info isKindOfClass: [Reachability class]], @"info was wrong class in ReachabilityCallback");

Reachability* noteObject = (__bridge Reachability *)info;
// Post a notification to notify the client that the network reachability changed.
[[NSNotificationCenter defaultCenter] postNotificationName: kReachabilityChangedNotification object: noteObject];

}`
the bug just appears in ios12, it totally seems fine in my ios10 simulator...

[854907646]

I meet the same question too.