Xcode 26.1 - [CBCentralManagerDelegate centralManagerDidUpdateState:]: unrecognized selector sent to instance

[james-allison]

Apple platform

iOS

Framework version

net10.0-*

Affected platform version

dotnet workload ios --version 10.0.100.1

Description

I've a dotnet maui app published with NativeAOT on iOS. It makes use of the CoreBluetooth API.

I tried building with the iOS workload supporting XCode 26.1 this morning (10.0.100.1), but the app immediately crashes due to an NSInvalidArgumentException:

-[CoreBluetooth_CBCentralManager__CBCentralManagerDelegate centralManagerDidUpdateState:]: unrecognized selector sent to instance 0x1042895c0

Rolling back to the previous workload (10.0.100.0) - the exception is not thrown.

I wasn't aware of any breaking changes with the CoreBluetooth API in 26.1 - so I'm assuming something has changed in how this is being wrapped by dotnet.

I'm developing on Windows, and can't currently (easily) debug this further with Visual Studio as the Xcode 26.1 workload isn't supported.

Steps to Reproduce

1. Create a CBCentralManager
2. Add a handler for the UpdatedState event.
3. I assume the PoweredOn event is triggering this crash - it happens instantly.

Did you find any workaround?

Revert to 10.0.100.0 iOS workload with xcode 26.0

Relevant log output

Last Exception Backtrace:
0   CoreFoundation                	0x1a14d28c8 __exceptionPreprocess + 164 (NSException.m:249)
1   libobjc.A.dylib               	0x19e4497c4 objc_exception_throw + 88 (objc-exception.mm:356)
2   CoreFoundation                	0x1a156e838 -[NSObject(NSObject) doesNotRecognizeSelector:] + 364 (NSObject.m:168)
3   CoreFoundation                	0x1a144f340 ___forwarding___ + 1032 (NSForwarding.m:3658)
4   CoreFoundation                	0x1a14573a0 _CF_forwarding_prep_0 + 96 (:-1)
5   CoreBluetooth                 	0x1de105c78 -[CBCentralManager observeValueForKeyPath:ofObject:change:context:] + 264 (CBCentralManager.m:257)
6   Foundation                    	0x19eb13b88 NSKeyValueNotifyObserver + 252 (NSKeyValueObserving.m:428)
7   Foundation                    	0x19eb137f4 NSKeyValueDidChange + 384 (NSKeyValueObserving.m:573)
8   Foundation                    	0x19f4125f8 -[NSObject(NSKeyValueObservingPrivate) _changeValueForKeys:count:maybeOldValuesDict:maybeNewValuesDict:usingBlock:] + 728 (NSKeyValueObserving.m:2669)
9   Foundation                    	0x19f4126a0 -[NSObject(NSKeyValueObservingPrivate) _changeValueForKey:key:key:usingBlock:] + 64 (NSKeyValueObserving.m:2684)
10  Foundation                    	0x19ec3e02c _NSSetLongLongValueAndNotify + 400 (NSKeyValueObserverNotifying.m:122)
11  CoreBluetooth                 	0x1de167c68 -[CBManager extractLocalDeviceStatesDictionary:] + 256 (CBManager.m:120)
12  CoreBluetooth                 	0x1de169184 -[CBManager xpcConnectionDidReceiveMsg:args:] + 76 (CBManager.m:583)
13  CoreBluetooth                 	0x1de1566d0 __30-[CBXpcConnection _handleMsg:]_block_invoke + 48 (CBXpcConnection.m:407)
14  libdispatch.dylib             	0x1d8ddeadc _dispatch_call_block_and_release + 32 (init.c:1575)
15  libdispatch.dylib             	0x1d8df87ec _dispatch_client_callout + 16 (client_callout.mm:85)
16  libdispatch.dylib             	0x1d8de7468 _dispatch_lane_serial_drain + 740 (queue.c:3991)
17  libdispatch.dylib             	0x1d8de7f78 _dispatch_lane_invoke + 440 (queue.c:4082)
18  libdispatch.dylib             	0x1d8de72d0 _dispatch_lane_serial_drain + 332 (queue.c:3991)
19  libdispatch.dylib             	0x1d8de7f78 _dispatch_lane_invoke + 440 (queue.c:4082)
20  libdispatch.dylib             	0x1d8e15a48 _dispatch_main_queue_drain.cold.5 + 592 (queue.c:8181)
21  libdispatch.dylib             	0x1d8dedec8 _dispatch_main_queue_drain + 180 (queue.c:8162)
22  libdispatch.dylib             	0x1d8dede04 _dispatch_main_queue_callback_4CF + 44 (queue.c:8341)
23  CoreFoundation                	0x1a1474520 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 16 (CFRunLoop.c:1820)
24  CoreFoundation                	0x1a1426d14 __CFRunLoopRun + 1944 (CFRunLoop.c:3177)
25  CoreFoundation                	0x1a1425c44 _CFRunLoopRunSpecificWithOptions + 532 (CFRunLoop.c:3462)
26  GraphicsServices              	0x2407fa498 GSEventRunModal + 120 (GSEvent.c:2049)
27  UIKitCore                     	0x1a6da0ddc -[UIApplication _run] + 792 (UIApplication.m:3899)
28  UIKitCore                     	0x1a6d45b0c UIApplicationMain + 336 (UIApplication.m:5574)

[mlancione]

I'm also seeing BLE issues using net10-ios 10.0.100.1 (Xcode 26.1) using this BLE library. The issues are not present with 10.0.100 (Xcode 26.0.1).
https://github.com/dotnet-bluetooth-le/dotnet-bluetooth-le

[rolfbjarne]

This might have the same underlying cause as #24262.

[rolfbjarne]

@james-allison can you try if adding this to the csproj works around it? That would confirm if it's a duplicate of #24262.

Adding this to the csproj should work around it:

<PropertyGroup>
    <AppBundleExtraOptions>--optimize=-register-protocols</AppBundleExtraOptions>
</PropertyGroup>

[mlancione]

--optimize=-register-protocols

I can confirm that adding that property fixed the BLE issues I was having with the dotnet-bluetooth-le library.

[rolfbjarne]

--optimize=-register-protocols

I can confirm that adding that property fixed the BLE issues I was having with the dotnet-bluetooth-le library.

Thanks for confirming!

[james-allison]

@rolfbjarne - With the extra option, the app is no longer throwing the exception and is working correctly.

Many thanks!

[bcaceiro]

@rolfbjarne this should be a temporary workaround or we can keep this in the project?

[rolfbjarne]

@rolfbjarne this should be a temporary workaround or we can keep this in the project?

The workaround disables a size optimization, so the app size might get a little bit bigger, but otherwise you can keep the workaround in the project if you wish.