I currently have a custom UITextView that properly changes the color of a link to the custom color I have set, however, when I click and hold the link, and the animation plays that makes the link bigger and creates a boarder around the link before previewing the website, the link changes briefly back to the system default color, and when letting go, it changes back to my custom color. Is there anyway to have the link always be my custom color, even when clicking and holding? struct AutoDetectedClickableDataView: UIViewRepresentable { let text: String let dataDetectors: UIDataDetectorTypes @Binding var height: CGFloat private func dataDectectorValue(_ dataDectecor: UIDataDetectorTypes) -> UInt64 { var checkingTypes: [NSTextCheckingResult.CheckingType] = [] if dataDetectors.contains(.phoneNumber) { checkingTypes.append(.phoneNumber) } if dataDetectors.contains(.link) { checkingTypes.append(.link) } if dataDetectors.contains(.address) { checkingTypes.append(.address) } if dataDetectors.contains(.calendarEvent) { checkingTypes.append(.date) } if checkingTypes.isEmpty { return 0 } let intCheckingTypes: UInt64 = checkingTypes.reduce(0) { result, checkingType in UInt64(result) | UInt64(checkingType.rawValue) } return intCheckingTypes } func makeUIView(context: Context) -> UITextView { let textView = UITextView() textView.dataDetectorTypes = dataDetectors textView.isEditable = false textView.isScrollEnabled = false textView.backgroundColor = .clear textView.font = UIFontMetrics(forTextStyle: .body).scaledFont(for: UIFont.systemFont(ofSize: 16.0), compatibleWith: textView.traitCollection) textView.textColor = UIColor.label textView.adjustsFontForContentSizeCategory = true textView.textContainer.lineBreakMode = .byWordWrapping textView.textContainerInset = .zero textView.textContainer.lineFragmentPadding = 0 textView.translatesAutoresizingMaskIntoConstraints = false textView.setContentCompressionResistancePriority(.defaultLow, for: .horizontal) textView.setContentHuggingPriority(.defaultHigh, for: .horizontal) textView.linkTextAttributes = [.foregroundColor: JeromesColors.UILinkColor] textView.tintColor = JeromesColors.UILinkColor for gesture in textView.gestureRecognizers ?? [] { if gesture is UITapGestureRecognizer { gesture.view?.tintColor = JeromesColors.UILinkColor } } return textView } func updateUIView(_ uiView: UITextView, context: Context) { let font = UIFontMetrics(forTextStyle: .body).scaledFont(for: UIFont.systemFont(ofSize: 16.0), compatibleWith: uiView.traitCollection) let color = UIColor.label let attributed = NSMutableAttributedString(string: text, attributes: [ .font: font, .foregroundColor: color ]) let detectorValue = dataDectectorValue(dataDetectors) var matchCount = 0 if !dataDetectors.isEmpty, detectorValue != 0 { let detector = try? NSDataDetector(types: detectorValue) detector?.enumerateMatches(in: text, options: [], range: NSRange(location: 0, length: text.utf16.count)) { match, _, _ in guard let match = match else { return } if match.resultType == .date, let date = match.date, date < Date() { return } else { attributed.addAttributes([ .foregroundColor: JeromesColors.UILinkColor, .underlineStyle: NSUnderlineStyle.single.rawValue, ], range: match.range) matchCount += 1 } } } uiView.attributedText = attributed if matchCount == 0 { uiView.isSelectable = false } else if matchCount > 0 { uiView.isSelectable = true } DispatchQueue.main.async { uiView.layoutIfNeeded() let fittingSize = CGSize(width: uiView.bounds.width, height: .greatestFiniteMagnitude) let size = uiView.sizeThatFits(fittingSize) height = size.height } } }

I am testing stuff on a website, and it worked well on any mobile browser till iOS18. Now that I am testing iOS26, even with the latest BETA (3) everything works smoothly on any other mobile browser but Safari. Previously I had the bug, which now has been patched, for status-bar, which was flickering too, but popover and page issue seems still there. I have persistent popover and ajax navigation, and both are rendering with bugs and fouc while view/page changes. Example: If I have an element which must stay on its place and its width is 100vw: while page changes it blinks, shrinks, flicker and jumps on rendering, while it simply must stay as is.. Animations and page transitions work smoothly on Chrome mobile (latest iOS 26 beta 3) , while breaking on Safari. I did open a feedback FB18328720, but seems no one caring. Any idea guys? ** Video of the bug (which is huge!) : ** https://youtube.com/shorts/rY3oxUwDd7w?feature=share Cheers

I'm experiencing a specific issue where when using any of the MacOS 26 Tahoe betas with Low Power Mode enabled and using Vsync in fullscreen, my application framerate gets limited to a hard 30 fps. I have not experienced this on any older OS. For example Low Power Mode on 13.6 Ventura with Vsync fullscreen lets my application run at full 60 fps without issues. Is this a bug or a change in behavior of Low Power Mode on Tahoe? My application is 3D, runs at 60 fps and is sensitive to tearing, so I need Vsync and it is mostly utilized in fullscreen. And Low Power Mode is a default for many Macs, so default experience on Tahoe currently is a halved 30 fps. However there also seems to be inconsistencies of on which machines this happens, but older OSes are always fine.

Hello everyone, I am having an issue where the attributed text that I have in my UITextView is not scaling dynamically with phone text size, whenever I remove the attributed text logic, it scales fine, however, with it, it stays at a set font size. struct AutoDetectedClickableDataView: UIViewRepresentable { let text: String @Binding var height: CGFloat func makeUIView(context: Context) -> UITextView { let textView = UITextView() textView.dataDetectorTypes = [.phoneNumber, .address, .link] textView.isEditable = false textView.isScrollEnabled = false textView.backgroundColor = .clear textView.font = UIFont.preferredFont(forTextStyle: .body) /*UIFontMetrics(forTextStyle: .body).scaledFont(for: UIFont.systemFont(ofSize: 16.0)) */ textView.adjustsFontForContentSizeCategory = true textView.textContainer.lineBreakMode = .byWordWrapping textView.textContainerInset = .zero textView.textContainer.lineFragmentPadding = 0 textView.translatesAutoresizingMaskIntoConstraints = false textView.setContentCompressionResistancePriority(.defaultLow, for: .horizontal) textView.setContentHuggingPriority(.defaultHigh, for: .horizontal) return textView } func updateUIView(_ uiView: UITextView, context: Context) { let attributed = NSMutableAttributedString(string: text, attributes: [ .font: UIFont.preferredFont(forTextStyle: .body) ]) let detector = try? NSDataDetector(types: NSTextCheckingResult.CheckingType.address.rawValue | NSTextCheckingResult.CheckingType.link.rawValue | NSTextCheckingResult.CheckingType.phoneNumber.rawValue) detector?.enumerateMatches(in: text, options: [], range: NSRange(location: 0, length: text.utf16.count)) { match, _, _ in guard let match = match else { return } attributed.addAttributes([ .foregroundColor: UIColor.systemBlue, .underlineStyle: NSUnderlineStyle.single.rawValue, ], range: match.range) } uiView.attributedText = attributed // uiView.text = text DispatchQueue.main.async { uiView.layoutIfNeeded() let fittingSize = CGSize(width: uiView.bounds.width, height: .greatestFiniteMagnitude) let size = uiView.sizeThatFits(fittingSize) height = size.height } } }

Good day everyone. I have a react native app which works on dev mode on my device - Iphone 13 pro version: 18.5, but when deployed to TestFlight and installed on same device it crashes when ever I click on any TextInput. I downloaded the crash file but finding it difficult to pinpoint the problem. I want to know what the problem is, if it's related to an installed package or code base or any other. Any help will be appreciated!!! Thanks. crashlog.crash

I am currently having an issue in where whenever I place a UITextView with text that's long, it simply pushes past the width of the container it is in, and when I do try and set a width, it does auto wrap and ignores that. I do not come from UIKit and come from SwiftUI, through a mix of ChatGPT and Stack overflow, I have come up with this solution, however, are there any better/simpler ones, I dont want to have to use expensive GeoReaders just to get a width. struct AutoDetectedPhoneNumberView: UIViewRepresentable { let text: String var width: CGFloat func makeUIView(context: Context) -> UITextView { let textView = UITextView() textView.dataDetectorTypes = [.phoneNumber] textView.isEditable = false textView.isScrollEnabled = false textView.backgroundColor = .clear textView.font = UIFont.systemFont(ofSize: 16) textView.textContainer.lineBreakMode = .byWordWrapping textView.translatesAutoresizingMaskIntoConstraints = false print(width) NSLayoutConstraint.activate([ textView.widthAnchor.constraint(equalToConstant: width) ]) return textView } func updateUIView(_ uiView: UITextView, context: Context) { uiView.text = text } } GeometryReader { geo in AutoDetectedPhoneNumberView(text: phone, width: geo.size.width) }

Thread 0 Crashed: 0 WebKit 0x00000001a1b6bf1c WKMouseDeviceObserver.connectedDeviceCount.setter + 68 (WKMouseDeviceObserver.swift:0) 1 WebKit 0x00000001a1b6bea4 @objc WKMouseDeviceObserver.connectedDeviceCount.setter + 152 2 WebKit 0x00000001a1b6d95c closure #2 in WKMouseDeviceObserver.start() + 80 (WKMouseDeviceObserver.swift:0) 3 WebKit 0x00000001a1b4e3e9 &lt;deduplicated_symbol&gt; + 1 4 WebKit 0x00000001a1b4e139 &lt;deduplicated_symbol&gt; + 1 5 WebKit 0x00000001a1b4e769 &lt;deduplicated_symbol&gt; + 1 6 libswift_Concurrency.dylib 0x0000000196037cdd completeTaskWithClosure(swift::AsyncContext*, swift::SwiftError*) + 1 (Task.cpp:546)

Whenever I load a resized image into a 70 by 70 frame, when I run the loading screen on the simulator, it looks like the image is flying from the top left corner of the screen on load, however, when I load it in the previews, it starts where its supposed to be in the center. Both are scaled properly, however, the first ones position is acting like I put a transition on it when I did not import SwiftUI struct LoadingView: View { @Environment(\.colorScheme) private var colorScheme var text: String? = nil @State private var isSpinning = false var body: some View { VStack{ Image("Jeromes_Logo") .resizable() .frame(width: 70, height: 70) .rotationEffect(.degrees(isSpinning ? 360 : 0)) .animation( .bouncy(duration: 0.4, extraBounce: 0.2) .repeatForever(autoreverses: false), value: isSpinning ) .onAppear { isSpinning = true } if let text = text { Text(text) } } .frame(maxWidth: .infinity, maxHeight: .infinity) } } #Preview { LoadingView(text: "loading") }

In my app, I implemented a screen recording functionality. But there was an unexpected crash. 0 CoreFoundation _CFRelease.cold.1 + 16 1 CoreFoundation ___CFTypeCollectionRelease 2 ReplayKit ___56-[RPScreenRecorder captureHandlerWithSample:timingData:]_block_invoke + 148 3 libdispatch.dylib __dispatch_call_block_and_release + 32 4 libdispatch.dylib __dispatch_client_callout + 16 5 libdispatch.dylib __dispatch_lane_serial_drain + 740 6 libdispatch.dylib __dispatch_lane_invoke + 388 7 libdispatch.dylib __dispatch_root_queue_drain_deferred_wlh + 292 8 libdispatch.dylib __dispatch_workloop_worker_thread + 540 9 libsystem_pthread.dylib __pthread_wqthread + 292

I downloaded Xcode 16 and updated my macOS to 15, but I keep getting this error when trying to build the game in simulator or in device [xrsimulator] Exception thrown: The operation couldn’t be completed. (realitytool.RKAssetsCompiler.RKAssetsCompilerError error 3.)

Has anyone here encountered this? It's driving me crazy. It appears on launch. App Sandbox is enabled. The proper entitlement is selected (com.apple.security.files.user-selected.read-write) I believe this is causing an issue with app functionality for users on different machines. There is zero documentation across the internet on this problem. I am on macOS 26 beta. This error appears in both Xcode and Xcode-beta. Please help! Thank you, Logan

Hi there, I'm experiencing several crashes on JavaScriptCore pas_panic_on_out_of_memory_error, only on devices with tvOS 15.4 and 15.4.1. This happens with users using the app for several hours as well as 5 seconds after launching the app. Devices: AppleTV6,2 and AppleTV5,3 Thread 14 — JavaScriptCore pas_panic_on_out_of_memory_error (JavaScriptCore) JavaScriptCore bmalloc_try_iso_allocate_impl_impl_slow (JavaScriptCore) JavaScriptCore bmalloc_heap_config_specialized_local_allocator_try_allocate_small_segregated_slow (JavaScriptCore) JavaScriptCore bmalloc_allocate_impl_casual_case (JavaScriptCore) JavaScriptCore ***::String::String(char16_t const*, unsigned int) (JavaScriptCore) JavaScriptCore JSC::LiteralParser<char16_t>::parsePrimitiveValue(JSC::VM&) (JavaScriptCore) JavaScriptCore JSC::LiteralParser<char16_t>::parse(JSC::ParserState) (JavaScriptCore) JavaScriptCore JSC::jsonProtoFuncParse(JSC::JSGlobalObject*, JSC::CallFrame*) (JavaScriptCore) JavaScriptCore llint_entry (JavaScriptCore) JavaScriptCore llint_entry (JavaScriptCore) JavaScriptCore llint_entry (JavaScriptCore) JavaScriptCore llint_entry (JavaScriptCore) JavaScriptCore vmEntryToJavaScript (JavaScriptCore) JavaScriptCore JSC::Interpreter::executeCall(JSC::JSGlobalObject*, JSC::JSObject*, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (JavaScriptCore) JavaScriptCore JSC::boundThisNoArgsFunctionCall(JSC::JSGlobalObject*, JSC::CallFrame*) (JavaScriptCore) JavaScriptCore vmEntryToNative (JavaScriptCore) JavaScriptCore JSC::Interpreter::executeCall(JSC::JSGlobalObject*, JSC::JSObject*, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (JavaScriptCore) JavaScriptCore JSC::profiledCall(JSC::JSGlobalObject*, JSC::ProfilingReason, JSC::JSValue, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (JavaScriptCore) JavaScriptCore JSObjectCallAsFunction (JavaScriptCore) JavaScriptCore -[JSValue invokeMethod:withArguments:] (JavaScriptCore) ITMLKit -[IKJSObject invokeMethod:withArguments:] (ITMLKit) ITMLKit -[IKJSEventListenerObject invokeMethod:withArguments:thenDispatchEvent:extraInfo:] (ITMLKit) ITMLKit __43-[IKJSXMLHTTPRequest setRequestReadyState:]_block_invoke (ITMLKit) ITMLKit -[IKAppContext _doEvaluate:] (ITMLKit) ITMLKit -[IKAppContext _evaluate:] (ITMLKit) ITMLKit __41-[IKAppContext evaluate:completionBlock:]_block_invoke (ITMLKit) ITMLKit -[IKAppContext _sourcePerform] (ITMLKit) ITMLKit -[IKConcurrentEvaluator lockSchedulingForEvaluation:] (ITMLKit) ITMLKit IKRunLoopSourcePerformCallBack (ITMLKit) CoreFoundation __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ (CoreFoundation) CoreFoundation __CFRunLoopDoSource0 (CoreFoundation) CoreFoundation __CFRunLoopDoSources0 (CoreFoundation) CoreFoundation __CFRunLoopRun (CoreFoundation) CoreFoundation CFRunLoopRunSpecific (CoreFoundation) ITMLKit -[IKAppContext _jsThreadMain] (ITMLKit) Foundation __NSThread__start__ (Foundation) libsyste...ad.dylib _pthread_start (libsystem_pthread.dylib) libsyste...ad.dylib thread_start (libsystem_pthread.dylib) This issue seems very similar to this existing thread, although not sure its related

Invalid Provisioning Profile. The provisioning profile included in the bundle XXX.XXX.XX [Payload/Runner.app/PlugIns/OneSignalNotificationServiceExtension.appex] is invalid. [Missing code-signing certificate]. A Distribution Provisioning profile should be used when submitting apps to the App Store. For more information, visit the iOS Developer Portal. With error code STATE_ERROR.VALIDATION_ERROR.90161 for id 81c3cef4-fefe-468d-910c-cf7a4b5377a8 Any help? I have tried to create new provisioning profile and identifiers but still get this error when uploading app to the App Store.

I'm trying to run(debug) an Xcode watch app project on my watch. My phone is connected to my computer via USB cable, my watch is paired to my phone. When I open Xcode and then open "Devices and simulators", I can see my phone properly connected. But these errors show up for my watch........ Apple Watch may need to be unlocked to recover from previously reported preparation errors Ensure the device is unlocked and associated with the same local area network as this Mac. A connection to this device could not be established. Timed out while attempting to establish tunnel using negotiated network parameters. I have booted computer, phone and watch. I have turned wifi off and on, on all 3 devices. I have turned developer mode on the watch off and then back on again. Anyone have any ideas how to fix this?

Hi, My app is using JavascriptCore to run the business logic in a javascript environment. We are randomly seeing crashes when users move the app back to the foreground. These crashes are reported by Firebase (I am attaching an example). I also tried to find them in Organizer, but the stacktraces don't match and I am not sure if they are pointing to the same error (I attach one just in case). I was trying to investigate a little bit about this, but I could find any explanation about what pas_reallocation_did_fail would mean. Here is our implementation: -(void) enqueueCallback:(JSValue *)callback withArguments:(NSArray *)args exclusive:(BOOL)exclusive { [self enqueueBlock:^{ @autoreleasepool { [callback callWithArguments:args]; } } exclusive:exclusive]; } Basically, every JS block is enqueued and then run by a dedicated thread specific to our JSContext. Can I get some help? Thanks in advance! Crashlytics.txt 2024-08-30_10-00-01.2572_-0400-f757f8306eda9679ec1b2ff90fbc66c4eb1fbee7.crash

For months now we're trying to find an issue with one of our apps, were a window suddenly becomes narrow and can't be resized horizontally any more. It's a bug that only happens sporadically and we can't provide a "focused test project" to demonstrate the issue; thus we can't ask for code-level support at this moment. To debug this issue, we've overwritten a private method on NSWindow that gets the constrained window min and max sizes (valuable hint of Kristin from the AppKit team in a WWDC 2025 one-on-one session where I was able to show it to her in my debugger). When the bug hits, the maxSize's width (usually 10000) becomes smaller than the minSize's width. One way (but not the only one) to trigger this issue is to move the window from one display to another and back. Sometimes the bug triggers after a few back-and-forth movements, sometimes it takes minutes to trigger or I give up… but for other people the bug happens seemingly out of nowhere (of course there must be a trigger but we haven't noticed common patterns yet). It looks like an AutoLayout issue since a suspicious thing happens when the bug triggers: calling constraintsAffectingLayoutForOrientation:NSLayoutConstraintOrientationHorizontal on the NSThemeFrame usually returns just two constraints. But when the bug triggers, it returns a whole bunch of constraints, related to all kind of views of our app. Asking the NSThemeFrame for its direct constraints still shows the same two constraints are present and active (NSWindow-current-width and NSWindow-x-anchor). How to proceed in hunting down this issue when we're unable to produce a demo project? We can only reproduce the bug with our big product, and only sporadically: sometimes I can trigger it in a minute, sometimes it takes me 15 minutes or even more. Issue happens on macOS 15 (currently running 15.5).

Hello, My app (daemon) time to time need to know list of GUI login sessions. According to the recommendation, I am using getutxent(). https://developer.apple.com/library/archive/qa/qa1133/_index.html However, I have faced with unclear behaviour in case of running "Migration Assistant". It can be re-created without my app. Steps to recreate: login as 'user #1' start "Migration Assistant" quit "Migration Assistant" new login prompt will be opened login as 'user #2' In spite the session of 'user #1' is closed, the command line tool "who", which gathers information from /var/run/utmpx, reports opened sessions of 'user #1'. Is it bug or feature? Thank you in advance!

Hi, I keep trying to use transformable to store an array of strings with SwiftData, and I can see that it is activating the transformer, but it keeps saying that I am still using NSArray instead of NSData. *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Unacceptable type of value for attribute: property = "category"; desired type = NSData; given type = Swift.__SwiftDeferredNSArray; value = ( yo, gurt ).' terminating due to uncaught exception of type NSException CoreSimulator 1010.10 - Device: iPhone 16 18.0 (6879535B-3174-4025-AD37-ED06E60291AD) - Runtime: iOS 18.0 (22A3351) - DeviceType: iPhone 16 Message from debugger: killed @Model class MyModel: Identifiable, Equatable { @Attribute(.transformable(by: StringArrayTransformer.self)) var category: [String]? @Attribute(.transformable(by: StringArrayTransformer.self)) var amenities: [String]? var image: String? var parentChunck: HenricoPostDataChunk_V1? init(category: [String]?, amenities: [String]?) { self.category = category self.amenities = amenities } } class StringArrayTransformer: ValueTransformer { override func transformedValue(_ value: Any?) -> Any? { print(value) guard let array = value as? [String] else { return nil } let data = try? JSONSerialization.data(withJSONObject: array, options: []) print(data) return data } override func reverseTransformedValue(_ value: Any?) -> Any? { guard let data = value as? Data else { return nil } let string = (try? JSONSerialization.jsonObject(with: data, options: [])) as? [String] print(string) return string } override class func transformedValueClass() -> AnyClass { return NSData.self } override class func allowsReverseTransformation() -> Bool { return true } static func register() { print("regitsering") ValueTransformer.setValueTransformer(StringArrayTransformer(), forName: .stringArrayTransformerName) } } extension NSValueTransformerName { static let stringArrayTransformerName = NSValueTransformerName("StringArrayTransformer") }

For a large / older iOS app project, we have noticed the the view hierarchy debugger works fine for our UIKit screens, but runs into the following crasher whenever we try to launch the view hierarchy debugger on a UIHostingVC screen with SwiftUI content: Unable to capture the view hierarchy "AppName" encountered an unexpected error when processing the request for a view hierarchy snapshot. -- The operation couldn’t be completed. Log Title: Data source expression execution failure. Log Details: error evaluating expression “(BOOL)[[(Class)objc_getClass("DebugHierarchyTargetHub") sharedHub] performRequestInPlaceWithRequestInBase64:@"..."]”: error: Execution was interrupted, reason: EXC_BAD_ACCESS (code=2, address=0x16b23bff8). Has anyone successfully resolved the underlying issue in this crasher? Tried all the typical recommendations for a clean build, clear derived data, use the "Debug -> View Debugging" menu - all with no resolution. Reported using Feedback Assistant: FB18514200 Thanks

I'm seeing somewhat regular crash reports from my app which appear to be deep in the Swift libraries. They're happening in the same spot, so I'm apt to believe something is likely getting deallocated behind the scenes - but I don't really know how to guard against it. Here's the specific crash thread: 0 libsystem_kernel.dylib 0x00000001d51261dc __pthread_kill + 8 (:-1) 1 libsystem_pthread.dylib 0x000000020eaa8b40 pthread_kill + 268 (pthread.c:1721) 2 libsystem_c.dylib 0x000000018c5592d0 abort + 124 (abort.c:122) 3 libsystem_malloc.dylib 0x0000000194d14cfc malloc_vreport + 892 (malloc_printf.c:251) 4 libsystem_malloc.dylib 0x0000000194d14974 malloc_report + 64 (malloc_printf.c:290) 5 libsystem_malloc.dylib 0x0000000194d0e8b4 ___BUG_IN_CLIENT_OF_LIBMALLOC_POINTER_BEING_FREED_WAS_NOT_ALLOCATED + 32 (malloc_common.c:227) 6 Foundation 0x0000000183229f40 __DataStorage.__deallocating_deinit + 104 (Data.swift:563) 7 libswiftCore.dylib 0x0000000182f556c8 _swift_release_dealloc + 56 (HeapObject.cpp:847) 8 libswiftCore.dylib 0x0000000182f5663c bool swift::RefCounts&lt;swift::RefCountBitsT&lt;(swift::RefCountInlinedness)1&gt;&gt;::doDecrementSlow&lt;(swift::PerformDeinit)1&gt;(swift::RefCountBitsT&lt;(swift::RefCountInlinedness)1&gt;, unsigned int) + 152 (RefCount.h:1052) 9 TAKAware 0x000000010240c688 StreamParser.parseXml(dataStream:) + 1028 (StreamParser.swift:0) 10 TAKAware 0x000000010240cdb4 StreamParser.processXml(dataStream:forceArchive:) + 16 (StreamParser.swift:85) 11 TAKAware 0x000000010240cdb4 StreamParser.parseCoTStream(dataStream:forceArchive:) + 360 (StreamParser.swift:108) 12 TAKAware 0x000000010230ac3c closure #1 in UDPMessage.connect() + 252 (UDPMessage.swift:68) 13 Network 0x000000018506b68c closure #1 in NWConnectionGroup.setReceiveHandler(maximumMessageSize:rejectOversizedMessages:handler:) + 200 (NWConnectionGroup.swift:458) 14 Network 0x000000018506b720 thunk for @escaping @callee_guaranteed (@guaranteed OS_dispatch_data?, @guaranteed OS_nw_content_context, @unowned Bool) -&gt; () + 92 (&lt;compiler-generated&gt;:0) 15 Network 0x0000000185185df8 invocation function for block in nw_connection_group_handle_incoming_packet(NWConcrete_nw_connection_group*, NSObject&lt;OS_nw_endpoint&gt;*, NSObject&lt;OS_nw_endpoint&gt;*, NSObject&lt;OS_nw_interface&gt;*, NSObje... + 112 (connection_group.cpp:1075) 16 libdispatch.dylib 0x000000018c4ad2b8 _dispatch_block_async_invoke2 + 148 (queue.c:574) 17 libdispatch.dylib 0x000000018c4b7584 _dispatch_client_callout + 16 (client_callout.mm:85) 18 libdispatch.dylib 0x000000018c4d325c _dispatch_queue_override_invoke.cold.3 + 32 (queue.c:5106) 19 libdispatch.dylib 0x000000018c4a21f8 _dispatch_queue_override_invoke + 848 (queue.c:5106) 20 libdispatch.dylib 0x000000018c4afdb0 _dispatch_root_queue_drain + 364 (queue.c:7342) 21 libdispatch.dylib 0x000000018c4b054c _dispatch_worker_thread2 + 156 (queue.c:7410) 22 libsystem_pthread.dylib 0x000000020eaa5624 _pthread_wqthread + 232 (pthread.c:2709) 23 libsystem_pthread.dylib 0x000000020eaa29f8 start_wqthread + 8 (:-1) Basically we're receiving a message via UDP that is an XML packet. We're parsing that packet using what I think it pretty straightforward code that looks like this: func parseXml(dataStream: Data?) -&gt; Array&lt;String&gt; { var events: [String] = [] guard let data = dataStream else { return events } currentDataStream.append(data) var str = String(decoding: currentDataStream, as: UTF8.self) while str.contains(StreamParser.STREAM_DELIMTER) { let splitEvent = str.split(separator: StreamParser.STREAM_DELIMTER, maxSplits: 1) let cotEvent = splitEvent.first! var restOfString = "" if splitEvent.count &gt; 1 { restOfString = String(splitEvent.last!) } events.append("\(cotEvent)\(StreamParser.STREAM_DELIMTER)") str = restOfString } currentDataStream = Data(str.utf8) return events } the intention is that the message may be broken across multiple packets, so we build them up here. Is there anything I can do to guard against these crashes?