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Bridging Headers is unsupported or Module compiled with Swift 5.5.1 cannot be imported by the Swift 5.6 complier
Hello guys! I faced a problem with building... My device suddenly updated to iOS 15.4.1, my Xcode was 13.2 and I had to update it to the latest version (13.3.1) to build the app. After the update, I had a few problems which were successfully solved but one of them stopped me for a few hours. The problem is with Bridging Headers or Swift Compiler, I really don't know what I did badly, and what causes problems. On several forums I often read that is important to set: Build Settings > Build Options > Build Libraries for Distribution But in any case it doesn't work, on yes: error: using bridging headers with module interfaces is unsupported on no: (line with import framework SWXMLHash) /Users/blablabla/SSLModel.swift:9:8: error: module compiled with Swift 5.5.1 cannot be imported by the Swift 5.6 compiler: /Users/blablabla2/Build/Products/Debug-iphoneos/SWXMLHash.framework/Modules/SWXMLHash.swiftmodule/arm64-apple-ios.swiftmodule import SWXMLHash It will be important that I use Carthage. What should I do? Clone all 10 frameworks that I use and re-build them with a new Xcode which includes compiler 5.6? That may be a bad solution... Any answers on similar topics don't help..
3
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2.9k
Jul ’25
IPad OS 16.1, Playgrounds and input fields
I have installed the latest beta on my iPad , iPadOS 16.1 (20B5050f) On running in app in Playgrounds that has a TextField, external keyboard input do not seem to be working. Tapping on the Text field inserts the cursor but no text can be entered on my external keyboard. (TextEditor field also do not work) Tested with both a Smart Keyboard and a Magic Keyboard. The keyboard works to enter the code in playgrounds, so it is not a keyboard connection issue. Disconnecting the keyboard, the onscreen keyboard is displayed and works correctly. Is this a Playgrounds issue or an iPadOS 16.1 issue or a compatibility issue with Playgrounds & iPadOS 16.1 ? import SwiftUI struct ContentView: View {     @State var field: String = "Test input"          var body: some View {         VStack {             Image(systemName: "globe")                 .imageScale(.large)                 .foregroundColor(.accentColor)             Text("Hello, world!")             TextField("", text: $field)                 .frame(height: 100)         }     } }
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1.5k
9h
error handling - Xcode shows error since Xcode Version > 15
Hello together, since Xcode Version > 15 the following error handling causes following error "Pattern of type 'DecodingError' cannot match 'Never' func getSupportedCountries() async { // fetch all documents from collection "seasons" from firestore let queryCountries = try? await db.collection("countries").getDocuments() if queryCountries != nil { self.countries = (queryCountries!.documents.compactMap({ (queryDocumentSnapshot) -> Country? in let result = Result { try? queryDocumentSnapshot.data(as: Country.self) } switch result { case .success(let country): if let country = country { // A country value was successfully initialized from the DocumentSnapshot self.errorMessage = nil return country } else { // A nil value was successfully initialized from the DocumentSnapshot, // or the DocumentSnapshot was nil self.errorMessage = "Document doesn't exist." return nil } case .failure(let error): // A Country value could not be initialized from the DocumentSnapshot switch error { case DecodingError.typeMismatch(_, let context): self.errorMessage = "\(error.localizedDescription): \(context.debugDescription)" case DecodingError.valueNotFound(_, let context): self.errorMessage = "\(error.localizedDescription): \(context.debugDescription)" case DecodingError.keyNotFound(_, let context): self.errorMessage = "\(error.localizedDescription): \(context.debugDescription)" case DecodingError.dataCorrupted(let key): self.errorMessage = "\(error.localizedDescription): \(key)" default: self.errorMessage = "Error decoding document: \(error.localizedDescription)" } return nil } })) } else { self.errorMessage = "No documents in 'countries' collection" return } } the interesting part of the code where XCODE shows an error is from "switch error" downwards. Does anyone of you have an idea what's wrong? Ay help appreciated ! Thx, Peter
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328
Jan ’25
NSExpression error handling
Context: SwiftUI TextField with a String for simple math using NSExpression. I first prepare the input string to an extent but a malformed input using valid characters still fails, as expected. Let's say preparedExpression is "5--" let expr = NSExpression(format: preparedExpression) gives FAULT: NSInvalidArgumentException: Unable to parse the format string "5-- == 1"; (user info absent) How can I use NSExpression such that either the preparedExpression is pre-tested before asking for actual execution or the error is handled in a polite way that I can use to alert the user to try again. Is there a Swift alternative to NSExpression that I've missed?
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499
Jan ’25
Why doesn’t getAPI() show up in autocomplete despite having a default implementation in a protocol extension?
I’m working on a project in Xcode 16.2 and encountered an issue where getAPI() with a default implementation in a protocol extension doesn’t show up in autocomplete. Here’s a simplified version of the code: import Foundation public protocol Repository { func getAPI(from url: String?) } extension Repository { public func getAPI(from url: String? = "https://...") { getAPI(from: url) } } final class _Repository: Repository { func getAPI(from url: String?) { // Task... } } let repo: Repository = _Repository() repo.getAPI( // Autocomplete doesn't suggest getAPI() I’ve tried the following without success: • Clean build folder • Restart Xcode • Reindexing Is there something wrong with the code, or is this a known issue with Xcode 16.2? I’d appreciate any insights or suggestions.
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512
Jan ’25
Casting `[String: Any]` to `[String: any Sendable]`
I have a simple wrapper class around WCSession to allow for easier unit testing. I'm trying to update it to Swift 6 concurrency standards, but running into some issues. One of them is in the sendMessage function (docs here It takes [String: Any] as a param, and returns them as the reply. Here's my code that calls this: @discardableResult public func sendMessage(_ message: [String: Any]) async throws -> [String: Any] { return try await withCheckedThrowingContinuation { (continuation: CheckedContinuation<[String: Any], Error>) in wcSession.sendMessage(message) { response in continuation.resume(returning: response) // ERROR HERE } errorHandler: { error in continuation.resume(throwing: error) } } } However, I get this error: Sending 'response' risks causing data races; this is an error in the Swift 6 language mode Which I think is because Any is not Sendable. I tried casting [String: Any] to [String: any Sendable] but then it says: Conditional cast from '[String : Any]' to '[String : any Sendable]' always succeeds Any ideas on how to get this to work?
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1
1.1k
Oct ’24
Passing string between Swift and C++
I want to understand what the recommended way is for string interoperability between swift and c++. Below are the 3 ways to achieve it. Approach 2 is not allowed at work due to restrictions with using std libraries. Approach 1: In C++: char arr[] = "C++ String"; void * cppstring = arr; std::cout<<"before:"<<(char*)cppstring<<std::endl;           // C++ String // calling swift function and passing the void buffer to it, so that swift can update the buffer content Module1::SwiftClass:: ReceiveString (cppstring, length);   std::cout<<"after:"<<(char*)cppstring<<std::endl;             // SwiftStr      In Swift: func ReceiveString (pBuffer : UnsafeMutableRawPointer , pSize : UInt ) -> Void { // to convert cpp-str to swift-str: let swiftStr = String (cString: pBuffer.assumingMemoryBound(to: Int8.self)); print("pBuffer content: \(bufferAsString)"); // to modify cpp-str without converting: let swiftstr:String = "SwiftStr"      _ =  swiftstr.withCString { (cString: UnsafePointer<Int8>) in pBuffer.initializeMemory(as: Int8.self, from: cString, count: swiftstr.count+1) } }  Approach 2:  The ‘String’ type returned from a swift function is received as ‘swift::String’ type in cpp. This is implicitly casted to std::string type. The std::string has the method available to convert it to char *. void TWCppClass::StringConversion () {     // GetSwiftString() is a swift call that returns swift::String which can be received in std::string type     std::string stdstr = Module1::SwiftClass::GetSwiftString ();     char * cstr = stdstr.data ();     const char * conststr= stdstr.c_str (); }    Approach 3: The swift::String type that is obtained from a swift function can be received in char * by directly casting the address of the swift::String. We cannot directly receive a swift::String into a char *. void TWCppClass::StringConversion () {    // GetSwiftString() is a swift call that returns swift::String    swift::String swiftstr = Module1::SwiftClass::GetSwiftString ();    // obtaining the address of swift string and casting it into char *    char * cstr = (char*)&swiftstr; }
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385
Jul ’25
Can i use c++ in swift app project
Can i use c++ library with c library in swift app project Hello. I want to use a C++ library in my Swift app project. First, our company has an internal solution library. When built, it generates a Static Library in '.a' format, and we use it by connecting the library's Header to the App_Bridging_Header. There's no problem with this part. However, the new feature now includes C++. It also generates a Static Library in '.a' format. So, I tried to use the same method and created an App_Bridging_Header. But an error occurs, and I can't proceed. The first error occurs in the library file: 'iostream' file not found The second error occurs in the App_Bridging_Header: failed to emit precompiled header '/Users/kimjitae/Library/Developer/Xcode/DerivedData/ddddd-glmnoqrwdrgarrhjulxjmalpyikr/Build/Intermediates.noindex/PrecompiledHeaders/ddddd-Bridging-Header-swift_3O89L0OXZ0CPD-clang_188AW1HK8F0Q3.pch' for bridging header '/Users/kimjitae/Desktop/enf4/ddddd/ddddd/ddddd-Bridging-Header.h' Our library is developed in C++ using Xcode, and there's no problem when we run and build just the library project. The build succeeds, and the '.a' file is generated correctly. However, when we try to connect it with the app, the above problems occur. Could there be a problem because we also need to use the existing C library alongside this? The build is successful in an app project created with Objective-C.
4
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617
Oct ’24
Interpreting received "Data" object in cpp
Hello Everyone, I have a use case where I wanted to interpret the "Data" object received as a part of my NWConnection's recv call. I have my interpretation logic in cpp so in swift I extract the pointer to the raw bytes from Data and pass it to cpp as a UnsafeMutableRawPointer. In cpp it is received as a void * where I typecast it to char * to read data byte by byte before framing a response. I am able to get the pointer of the bytes by using // Swift Code // pContent is the received Data if let content = pContent, !content.isEmpty { bytes = content.withUnsafeBytes { rawBufferPointer in guard let buffer = rawBufferPointer.baseAddress else { // return with null data. } // invoke cpp method to interpret data and trigger response. } // Cpp Code void InterpretResponse (void * pDataPointer, int pDataLength) { char * data = (char *) pDataPointer; for (int iterator = 0; iterator < pDataLength; ++iterator ) { std::cout << data<< std::endl; data++; } } When I pass this buffer to cpp, I am unable to interpret it properly. Can someone help me out here? Thanks :) Harshal
4
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947
Dec ’24
Include swift class as an Instance variable in a C++ class
Is there a way to achieve the following using C++/Swift interoperability: class MyCppClass { public: ... ... private: bool member1; ACppClass member2; ASwiftClass member3; } I'm aware of the recent C++/Objective-C interoperability compiler setting, but can't find any information on whether this is possible. I've watched the Apple video: https://developer.apple.com/videos/play/wwdc2023/10172/ and seen this post from Quinn: https://developer.apple.com/forums/thread/768928 but I don't see anyone discussing this kind of situation. Thanks in advance.
4
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91
Mar ’25
How to break `while` loop and `deliver partial result to `View`?
I make some small program to make dots. Many of them. I have a Generator which generates dots in a loop: //reprat until all dots in frame while !newDots.isEmpty { virginDots = [] for newDot in newDots { autoreleasepool{ virginDots.append( contentsOf: newDot.addDots(in: size, allDots: &result, inSomeWay)) } newDots = virginDots } counter += 1 print ("\(result.count) dots in \(counter) grnerations") } Sometimes this loop needs hours/days to finish (depend of inSomeWay settings), so it would be very nice to send partial result to a View, and/or if result is not satisfying — break this loop and start over. My understanding of Tasks and Concurrency became worse each time I try to understand it, maybe it's my age, maybe language barier. For now, Button with {Task {...}} action doesn't removed Rainbow Wheel from my screen. Killing an app is wrong because killing is wrong. How to deal with it?
4
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433
Nov ’24
Help Understanding Concurrency Error with Protocol Listener and Actor
Hi all, I'm running into a Swift Concurrency issue and would appreciate some help understanding what's going on. I have a protocol and an actor set up like this: protocol PersistenceListener: AnyObject { func persistenceDidUpdate(key: String, newValue: Any?) } actor Persistence { func addListener(_ listener: PersistenceListener) { listeners.add(listener) } /// Removes a listener. func removeListener(_ listener: PersistenceListener) { listeners.remove(listener) } // MARK: - Private Properties private var listeners = NSHashTable<AnyObject>.weakObjects() // MARK: - Private Methods /// Notifies all registered listeners on the main actor. private func notifyListeners(key: String, value: Any?) async { let currentListeners = listeners.allObjects.compactMap { $0 as? PersistenceListener } for listener in currentListeners { await MainActor.run { listener.persistenceDidUpdate(key: key, newValue: value) } } } } When I compile this code, I get a concurrency error: "Sending 'listener' risks causing data races"
4
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98
Apr ’25
Symbol not found: _swift_getTypeByMangledNameInContext2
We have MacOS application which uses Network Extensions. When building it with XCode 15 and 15.0.1 the extension crashes on Intel based Macs with the following error: Symbol not found: _swift_getTypeByMangledNameInContext2 Expected in: /usr/lib/swift/libswiftCore.dylib We tested it on Big Sur and Ventura with the same outcome. On Ventura when running on Intel based Mac libswiftCore.dylib really doesn't provide this symbol: nm -g libswiftCore.dylib | grep Mangle 00007ff80faf6150 T _$ss031_getFunctionFullNameFromMangledD007mangledD0SSSgSS_tF 00007ff80fcc4460 T _swift_getFunctionFullNameFromMangledName 00007ff80fcc40b0 T _swift_getMangledTypeName 00007ff80fcf7ed0 T _swift_getTypeByMangledName 00007ff80fcf8230 T _swift_getTypeByMangledNameInContext 00007ff80fcf8370 T _swift_getTypeByMangledNameInContextInMetadataState 00007ff80fcf7d90 T _swift_getTypeByMangledNameInEnvironment 00007ff80fcf80f0 T _swift_getTypeByMangledNameInEnvironmentInMetadataState 00007ff80fcfb460 T _swift_getTypeByMangledNode Is there any workaround for this issue? Crash log is the following: Thread 0 Crashed:: Dispatch queue: com.apple.main-thread 0 dyld 0x000000010a165f7a __abort_with_payload + 10 1 dyld 0x000000010a18ef40 abort_with_payload_wrapper_internal + 80 2 dyld 0x000000010a18ef72 abort_with_payload + 9 3 dyld 0x000000010a10f14a dyld::halt(char const*) + 672 4 dyld 0x000000010a10f274 dyld::fastBindLazySymbol(ImageLoader**, unsigned long) + 167 5 libdyld.dylib 0x00007fff203b3376 dyld_stub_binder + 282 6 ??? 0x0000000104b086a0 0 + 4373644960 7 com.xxxx.Tunnel 0x00000001049d318a 0x10489e000 + 1266058 8 com.xxxx.Tunnel 0x00000001049df35d 0x10489e000 + 1315677 9 com.xxxx.Tunnel 0x00000001048a0765 0x10489e000 + 10085 10 com.apple.ExtensionKit 0x00007fff31bda683 __112-[EXConcreteExtensionContextVendor _beginRequestWithExtensionItems:listenerEndpoint:withContextUUID:completion:]_block_invoke + 808 11 libdispatch.dylib 0x00007fff201ec5dd _dispatch_call_block_and_release + 12 12 libdispatch.dylib 0x00007fff201ed7c7 _dispatch_client_callout + 8 13 libdispatch.dylib 0x00007fff201f9b86 _dispatch_main_queue_callback_4CF + 940 14 com.apple.CoreFoundation 0x00007fff204ce356 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 9 15 com.apple.CoreFoundation 0x00007fff20490188 __CFRunLoopRun + 2745 16 com.apple.CoreFoundation 0x00007fff2048efe2 CFRunLoopRunSpecific + 567 17 com.apple.Foundation 0x00007fff21151fa1 -[NSRunLoop(NSRunLoop) runMode:beforeDate:] + 212 18 com.apple.Foundation 0x00007fff211e0384 -[NSRunLoop(NSRunLoop) run] + 76 19 libxpc.dylib 0x00007fff200e53dd _xpc_objc_main + 825 20 libxpc.dylib 0x00007fff200e4e65 xpc_main + 437 21 com.apple.Foundation 0x00007fff211732bd -[NSXPCListener resume] + 262 22 com.apple.pluginkit.framework 0x00007fff2b288273 0x7fff2b26d000 + 111219 23 com.apple.pluginkit.framework 0x00007fff2b287efb 0x7fff2b26d000 + 110331 24 com.apple.pluginkit.framework 0x00007fff2b288639 0x7fff2b26d000 + 112185 25 com.apple.ExtensionKit 0x00007fff31be6d05 EXExtensionMain + 70 26 com.apple.Foundation 0x00007fff211e2479 NSExtensionMain + 208 27 libdyld.dylib 0x00007fff203b4621 start + 1
4
0
1.6k
Oct ’24
Testing the content of a `Task` in a non-async method
Hi, Considering this method I'd like to test: public func play(_ soundFileName: String, shouldLoop: Bool) { Task { await dataSource.play(soundFileName, shouldLoop: shouldLoop) } } Previously, with XCTest we could use an expectation and wait for it to be fulfilled: func test() sut.play("", shouldLoop: false) wait(for: [mockedAudioPlayerDataSource.invokedPlayExpectation]) XCTAssertEqual(mockedAudioPlayerDataSource.invokedPlayCount, 1) With Swift Testing, I am unsure what a unit test looks like.
4
0
936
Oct ’24
Warning: Reference to captured var 'hashBag' in concurrently-executing code
I get many warnings like this when I build an old project. I asked AI chatbot which gave me several solutions, the recommended one is: var hashBag = [String: Int]() func updateHashBag() async { var tempHashBag = hashBag // make copy await withTaskGroup(of: Void.self) { group in group.addTask { tempHashBag["key1"] = 1 } group.addTask { tempHashBag["key2"] = 2 } } hashBag = tempHashBag // copy back? } My understanding is that in the task group, the concurrency engine ensures synchronized modifications on the temp copy in multiple tasks. I should not worry about this. My question is about performance. What if I want to put a lot of data into the bag? Does the compiler do some kind of magics to optimize low level memory allocations? For example, the temp copy actually is not a real copy, it is a special reference to the original hash bag; it is only grammar glue that I am modifying the copy.
4
0
116
Apr ’25
Memory leaks caused by closures
Hi there, this is my first time posting here. I've heard that some of the apple developers are usually active on these forums, so I've decided to shoot my shot, because this question was driving me crazy for a few days now and nobody could yet give me a clear view on what's actually happening. Here is the first snippet of the code class Animal { var name = "Fischer" var command: () -> Void = { } deinit { print(#function, #line) } } do { var pet: Animal? = Animal() pet?.command = { print(pet?.name ?? "Bobby") } } This code causes a memory leak, because Reference 'pet' is created. Independent copy of the reference 'pet' is created inside the closure. now there are two references to the same object, which are 'pet' outside the closure and 'pet' inside the closure. As we exit the 'do' scope, the 'pet' reference is deleted, but ARC does not deallocate the object due to the strong reference 'pet', that is still referencing to the same object. And all of that causes a memory leak. Now here is the code, that is pretty similar, except for the fact, that we assign a nil to the 'pet' reference class Animal { var name = "Fischer" var command: () -> Void = { } deinit { print(#function, #line) } } do { var pet: Animal? = Animal() pet?.command = { print(pet?.name ?? "Bobby") } pet = nil } And boom! deinit is called, meaning that the object was deallocated, but how? Why was the object deallocated? If we are deleting the exact same reference, that was deleted by the end of the 'do' scope in the first snippet? Am I misunderstanding something? I really hope this post will find the right people, since I could not even find appropriate tags for that.
4
0
674
Oct ’24