We're facing a reproducible crash on iOS 17 that seems to be related to our ToolbarItems. It happens when we tear down a NavigationStack (by setting all navigationDestination Bindings to false), where the same view is present multiple times in the stack. This happens in about 20% of the time and only on a real iOS device: Simultaneous accesses to 0x144a23a60, but modification requires exclusive access. Previous access (a modification) started at SwiftUI` + 12312 (0x1a5595a34). The stacktrace goes from [UIBarButtonItem dealloc] -> AG::Subgraph::notify_observers() -> swift::runtime::AccessSet::insert(swift::runtime::Access*, void*, void*, swift::ExclusivityFlags) The "Current access (a read) started at:" info points to a very similar stacktrace (see the screenshot I linked below). I failed to attach the crash report to this post, but have uploaded it here: https://www.dropbox.com/scl/fi/7lrwkuhge0dmz1grv9r3r/SwiftUI-ToolbarItem-Crash.txt?rlkey=pu0x835y25uy38r605qflhhtm&dl=0. This is the Stacktrace from Xcode: https://www.dropbox.com/scl/fi/fdijajvq60jd7wawlsdjr/SwiftUI-ToolbarItem-Crash.png?rlkey=m05ahqihliji32udbcmd6yz0a&dl=0 Is there anything I can do to narrow down the root cause? A workaround would be to remove the ToolbarItems and fake a navigation controller, but I would like to avoid such hacks.

We want to use AccessorySetupKit to pair our BLE accessories. However, currently all our products announce the same BLE service UUID. The manufacturer data is different for every product. I try to pair our products with ASK and create the ASDiscoveryDescriptor with the expected manufacturer data: let descriptorA = ASDiscoveryDescriptor() descriptorA.bluetoothServiceUUID = CBUUID("CE1EB45C-1BD2-45BE-8163-ACC88BE94CB2") // same descriptorA.bluetoothManufacturerDataBlob = Data([0xd2, 0x0a, 0x00, /* A */ 0x2a, 0x00, 0x00, 0x00]) // different descriptorA.bluetoothManufacturerDataMask = Data([0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff]) let descriptorB = ASDiscoveryDescriptor() descriptorB.bluetoothServiceUUID = CBUUID("CE1EB45C-1BD2-45BE-8163-ACC88BE94CB2") // same descriptorB.bluetoothManufacturerDataBlob = Data([0xd2, 0x0a, 0x00, /* B */ 0x2b, 0x00, 0x00, 0x00]) // different descriptorB.bluetoothManufacturerDataMask = Data([0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff]) However, it seems random which device is found, as if the service UUID is the primary key to handle things in ASK. My questions are: Is it possible to use only manufacturer data to distinguish between different products with the same service UUID? How do I use bluetoothManufacturerDataMask properly? I assume that internally some filtering like this is done: DataBlob & DataMask == ReceivedManufacturerData & DataMask. Because of that I have set all bits of the mask to 1. Should this e done differently?