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Is there any way to retrieve the memory pressure percentage using native libraries?
When I run the memory-pressure command, I can see the percentage of free memory, but I’d like to retrieve the same information using a native library.
Topic:
Programming Languages
SubTopic:
Swift
I can't find any simple c++ xcodeproj call to swift struct using modern c++ swift mix. there is the fibonacci example that is swift app call to c++.
Base on fibonacci example I create new simple project and fail to build it with error when I try to include #include <SwiftMixTester/SwiftMixTester-Swift.h>
What is wrong?
Is it the right place to ask this?
Any work project link?
Xcode 26.
Topic:
Programming Languages
SubTopic:
Swift
I have c++ macOs app(Xcode +14) and I try to add call to swift code.
I can't find any simple c++ xcodeproj call to swift code.
I create new simple project and fail to build it with error when I try to include #include <SwiftMixTester/SwiftMixTester-Swift.h>:
main.m:9:10: error: 'SwiftMixTester/SwiftMixTester-Swift.h' file not found (in target 'CppCallSwift' from project 'CppCallSwift')
note: Did not find header 'SwiftMixTester-Swift.h' in framework 'SwiftMixTester' (loaded from '/Users/yanivsmacm4/Library/Developer/Xcode/DerivedData/CppCallSwift-exdxjvwdcczqntbkksebulvfdolq/Build/Products/Debug') .
Please help.
Error: "Attrubute can only be applied to types not declarations" on line 2 : @unchecked
@unchecked
enum ReminderRow : Hashable, Sendable {
case date
case notes
case time
case title
var imageName : String? {
switch self {
case .date: return "calendar.circle"
case .notes: return "square.and.pencil"
case .time: return "clock"
default : return nil
}
}
var image : UIImage? {
guard let imageName else { return nil }
let configuration = UIImage.SymbolConfiguration(textStyle: .headline)
return UIImage(systemName: imageName, withConfiguration: configuration)
}
var textStyle : UIFont.TextStyle {
switch self {
case .title : return .headline
default : return .subheadline
}
}
}
Xcode downloaded a crash report for my app that crashed when trying to insert a String into a Set<String>. Apparently there was an assertion failure ELEMENT_TYPE_OF_SET_VIOLATES_HASHABLE_REQUIREMENTS. I assume that this assertion failure happened because the hash of the new element didn't match the hash of an equal already inserted element, but regardless, I don't understand how inserting a simple string could trigger this assertion.
Here is essentially the code that leads to the crash. path is any file system directory, and basePath is a directory higher in the hierarchy, or path itself.
var scanErrorPaths = Set<String>()
func main() {
let path = "/path/to/directory"
let basePath = "/path"
let fileDescriptor = open(path, O_RDONLY)
if fileDescriptor < 0 {
if (try? URL(fileURLWithPath: path, isDirectory: false).checkResourceIsReachable()) == true {
scanErrorPaths.insert(path.relativePath(from: basePath)!)
return
}
}
extension String {
func relativePath(from basePath: String) -> String? {
if basePath == "" {
return self
}
guard let index = range(of: basePath, options: .anchored)?.upperBound else {
return nil
}
return if index == endIndex || basePath == "/" {
String(self[index...])
} else if let index = self[index...].range(of: "/", options: .anchored)?.upperBound {
String(self[index...])
} else {
nil
}
}
}
crash.crash
Undefined symbols for architecture arm64:
"_swift_coroFrameAlloc", referenced from:
NvMobileCore.Constraint.isActive.modify : Swift.Bool in NvMobileCore[5]
NvMobileCore.Constraint.isActive.modify : Swift.Bool in NvMobileCore[5]
NvMobileCore.NvMobileCoreManager.delegate.modify : NvMobileCore.NvPublicInterface? in NvMobileCore[53]
NvMobileCore.NvMobileCoreManager.delegate.modify : NvMobileCore.NvPublicInterface? in NvMobileCore[53]
NvMobileCore.NvMobileCoreManager.language.modify : Swift.String in NvMobileCore[53]
NvMobileCore.NvMobileCoreManager.language.modify : Swift.String in NvMobileCore[53]
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
When i am trying to archive a framework for ML, using below command:
xcodebuild -workspace "./src/MLProject.xcworkspace" -configuration "Release" -sdk "iphoneos" -archivePath "./gen/out/Archives/Release-iphoneos/MLProject" -scheme "MLProject" -derivedDataPath "./gen/out/" archive BUILD_LIBRARY_FOR_DISTRIBUTION=YES SKIP_INSTALL=NO
The same command used to work fine on Xcode 16.4.
Attached is the detailed error
MLProject_Archive_failure.txt
Hello Everyone! I started programming 6 months ago and started Swift / IOS last month. My learning so far has mainly been with Python. I learned a lot of the package ‘SQLAlchemy’, which has very ‘example based’ documentation. If I wanted to learn how to make a many to many relationship, there was a demonstration with code. But going into Swift and Apple packages, I notice most of the documentation is definitions of structures, modifiers, functions, etc. I wanted to make the equivalent of python ‘date times’ in my swift app. I found the section in the documentation “Foundation->Dates & Times”, but I couldn’t figure how to use that in my code.
I assume my goal should not be to memorize every Swift and apple functionality by memory to be an app developer. So I would appreciate advice on how to approach this aspect of learning programming.
Topic:
Programming Languages
SubTopic:
Swift
Hi, I've got this view model that will do a search using a database of keywords. It worked fine when the SearchEngine wasn't an actor but a regular class and the SearchResult wasn't a Sendable. But when I changed them, it returned Type of expression is ambiguous without a type annotation error at line 21 ( searchTask = Task {). What did I do wrong here? Thanks.
protocol SearchableEngine: Actor {
func searchOrSuggest(from query: String) -> SearchResult?
func setValidTitles(_ validTitles: [String])
}
@MainActor
final class SearchViewModel: ObservableObject {
@Published var showSuggestion: Bool = false
@Published var searchedTitles: [String] = []
@Published var suggestedKeyword: String? = nil
private var searchTask: Task<Void, Never>?
private let searchEngine: SearchableEngine
init(searchEngine: SearchableEngine) {
self.searchEngine = searchEngine
}
func search(_ text: String) {
searchTask?.cancel()
searchTask = Task {
guard !Task.isCancelled else { return }
let searchResult = await searchEngine.searchOrSuggest(from: text) ?? .notFound
guard !Task.isCancelled else { return }
await MainActor.run {
switch searchResult {
case let .searchItems(_, items):
showSuggestion = false
searchedTitles = items.map(\.title)
suggestedKeyword = nil
case let .suggestion(keyword, _, items):
showSuggestion = true
searchedTitles = items.map(\.title)
suggestedKeyword = keyword
case .notFound:
showSuggestion = false
searchedTitles = []
suggestedKeyword = nil
}
}
}
}
}
Is anyone have this problem on xcode 26 ?
Undefined symbol: _swift_FORCE_LOAD$_swiftCompatibility50
Undefined symbol: _swift_FORCE_LOAD$_swiftCompatibility51
Undefined symbol: _swift_FORCE_LOAD$_swiftCompatibility56
Undefined symbol: _swift_FORCE_LOAD$_swiftCompatibilityConcurrency
Undefined symbol: _swift_FORCE_LOAD$_swiftCompatibilityDynamicReplacements
I can't find the arm_neon.h header file in macOS 15.6.1
This header file defines NEON intrinsics.
Hello
I want to implement customisation to swift argumentparser, Here are following changes want to do it in my cli
changing default footer present in help command output
currently help command output coming like this
OVERVIEW: clisample
USAGE: clisample <subcommand>
OPTIONS:
--version show the version.
-h, --help show the help.
SUBCOMMANDS:
logs (default) Export logs for clisample processes.
See 'clisample --help' for more information.'
so instead of
See 'clisample --help' for more information.'
I want my own string
For more details, run 'clisample help <subcommand>'
customise error string getting from validation error
Error: Missing value for '-t <time>'
Help: -t <time> Time window (e.g. 10h, 30m, 2d).
Usage: clisample logs --time <time>
See 'clisample logs --help' for more information.
so I want error output with example and customised footer, like this
Error: Missing value for '-t <time>'
Help: -t <time> Time window (e.g. 10h, 30m, 2d).
Usage: clisample logs --time <time>
Example: clisample logs -t 5m
For more details, run 'clisample help <subcommand>'
Is this changes possible from anyway?
I am an SDK provider working with Swift Package Manager (SPM) to deliver libraries for iOS developers. My SDK currently uses SPM targets to modularize functionality. However, SPM enforces strict resource bundling, which prevents me from efficiently offering multiple targets—each with a different set of localization files—in a single package.
Current Limitation:
When multiple SPM targets share the same source and resource directory but require distinct sets of .lproj localization folders (for app size or client requirements), SPM raises “overlapping sources” errors. The only workaround is to manually split resource directories or have clients prune localizations post-build, which is inefficient and error-prone.
Feature Request:
Please consider adding native support in Swift Package Manager for:
Defining multiple targets within a single package that can process overlapping source/resource directories,
Each target specifying a distinct subset of localization resource files via the exclude or a new designated parameter,
Enabling efficient modular delivery of SDKs to clients needing different localization payloads, without redundant resource duplication or error-prone manual pruning.
Support for this feature would greatly ease SDK distribution, lower app sizes, and improve package maintainability for iOS and all Swift platforms.
I’m stuck with repeated production crashes in my SwiftUI app and I can’t make sense of the traces on my own.
The symbolicated reports show the same pattern:
Crash on com.apple.CFNetwork.LoaderQ with EXC_BAD_ACCESS / PAC failure
Always deep in CFNetwork, most often in
URLConnectionLoader::loadWithWhatToDo(NSURLRequest*, _CFCachedURLResponse const*, long, URLConnectionLoader::WhatToDo)
No frames from my code, no sign of AuthManager or tokens.
What I’ve tried:
Enabled Address Sanitizer,
Malloc Scribble,
Guard Malloc,
Zombies.
Set CFNETWORK_DIAGNOSTICS=3 and collected Console logs.
Stress-tested the app (rapid typing, filter switching, background/foreground, poor network with Network Link Conditioner).
Could not reproduce the crash locally.
So far:
Logs show unrelated performance faults (I/O on main thread, CLLocationManager delegate), but no obvious CFNetwork misuse.
My suspicion is a URLSession lifetime or delegate/auth-challenge race, but I can’t confirm because I can’t trigger it.
Since starting this investigation, I also refactored some of my singletons into @State/@ObservedObject dependencies. For example, my app root now wires up AuthManager, BackendService, and AccountManager (where API calls happen using async/await) as @State properties:
@State var authManager: AuthManager
@State var accountManager: AccountManager
@State var backendService: BackendService
init() {
let authManager = AuthManager()
self._authManager = .init(wrappedValue: authManager)
let backendService = BackendService(authManager: authManager)
self._backendService = .init(wrappedValue: backendService)
self._accountManager = .init(wrappedValue: AccountManager(backendService: backendService))
}
I don’t know if this refactor is related to the crash, but I am including it to be complete.
Apologies that I don’t have a minimized sample project — this issue seems app-wide, and all I have are the crash logs.
Request:
Given the crash location (URLConnectionLoader::loadWithWhatToDo), can Apple provide guidance on known scenarios or misuses that can lead to this crash?
Is there a way to get more actionable diagnostics from CFNetwork beyond CFNETWORK_DIAGNOSTICS to pinpoint whether it’s session lifetime, cached response corruption, or auth/redirect?
Can you also confirm whether my dependency setup above could contribute to URLSession or backend lifetime issues?
I can’t reliably reproduce the crash, and without Apple’s insight the stack trace is effectively opaque to me.
Thanks for your time and help. Happy to send multiple symbolicated crash logs at request.
Thanks for any help.
PS. Including 2 of many similar crash logs. Can provide more if needed.
Atlans-2025-07-29-154915_symbolicated (cfloader).txt
Atlans-2025-08-08-124226_symbolicated (cfloader).txt
Hello,
While watching WWDC25: Code-along: Elevate an app with Swift concurrency at timestamp 25:48, I noticed something in the slide/diagram that might be incorrect.
The diagram shows ExtractSticker twice, but based on the code context and spoken explanation, I think it was meant to be ExtractSticker and ExtractColor.
Reasoning:
The surrounding code and narration describe the use of async let and a Sendable Data object.
From the flow, one task extracts a sticker while the other extracts a color, so it seems like the diagram is inconsistent.
I do understand that with @concurrent, having two ExtractSticker operations on the same Data is technically possible (with two concurrent process executing their respective ExtractSticker) — but that would be a different meaning than what the talk was describing.
Since concurrency is already a subtle and error-prone topic, I thought it was worth pointing this out. If I’m mistaken, I’d love clarification. Otherwise, this could be a small correction to keep things aligned and clearer for everyone.
Minor point overall, but Swift 6’s concurrency model is doing a fantastic job at helping us write safer code—so thank you to the team for that!
(Attaching screenshots for reference)
I filed the following issue on swiftlang/swift on GitHub (Aug 8th), and a followup the swift.org forums, but not getting any replies. As we near the release of Swift 6.2, I want to know if what I'm seeing below is expected, or if it's another case where the compiler needs a fix.
protocol P1: Equatable { }
struct S1: P1 { }
// Error: Conformance of 'S1' to protocol 'P1' crosses into main actor-isolated code an can cause data races
struct S1Workaround: @MainActor P1 { } // OK
// Another potential workaround if `Equatable` conformance can be moved to the conforming type.
protocol P2 { }
struct S2: Equatable, P2 { } // OK
There was a prior compiler bug fix which addressed inhereted protocols regarding @MainActor. For Equatable, one still has to use @MainActoreven when the default actor isolation is MainActor.
Also affects Hashable and any other protocol inheriting from Equatable.
func oneStepForward(_ input: Int) -> Int {
return input + 1
}
func oneStepBackward(_ input: Int) -> Int {
return input - 1
}
func chooseStepFunction(backward: Bool) -> (Int) -> Int {
return backward ? oneStepBackward : oneStepForward
//Error. type of expression is ambiguous without a type annotation
}
Why am I getting this error ?
If I change this function to the following it works and will compile.
func chooseStepFunction(backward: Bool) -> (Int) -> Int {
if backward {
return oneStepBackward
} else {
return oneStepForward
}
}
// Why am I getting the error in the previous version while it works in the second version ?
Thx in advance.
Greetings,
func stepForward(_ input: Int) -> Int {
return input + 1
}
func stepBackward(_ input: Int) -> Int {
return input - 1
}
func chooseStepFunction(backward: Bool) -> (Int) -> Int {
return backward ? stepBackward : stepForward /* Error
type of expression is ambiguous without a type annotation */
}
Why am I getting this error. If I change the function to
func chooseStepFunction(backward: Bool) -> (Int) -> Int {
if backward {
return stepBackward
else {
return stepForward
}
}
Why is the previous chooseStepFunction giving me an error ?
Thx in advance
Is this possible while inserting a String into Set
Crashed: com.apple.root.user-initiated-qos.cooperative
0 libswiftCore.dylib 0xf4c0 _assertionFailure(_:_:flags:) + 136
1 libswiftCore.dylib 0x17f484 ELEMENT_TYPE_OF_SET_VIOLATES_HASHABLE_REQUIREMENTS(_:) + 3792
2 MyEatApp 0x44f6e8 specialized _NativeSet.insertNew(_:at:isUnique:) + 4333926120 (<compiler-generated>:4333926120)
3 MyEatApp 0x44eaec specialized Set._Variant.insert(_:) + 4333923052 (<compiler-generated>:4333923052)
4 MyEatApp 0x479f7c HomeViewModel.hanldeAnnouncementCard(from:) + 293 (HomeViewModel+PersonalizedOffer.swift:293)
5 libswift_Concurrency.dylib 0x5c134 swift::runJobInEstablishedExecutorContext(swift::Job*) + 292
6 libswift_Concurrency.dylib 0x5d5c8 swift_job_runImpl(swift::Job*, swift::SerialExecutorRef) + 156
7 libdispatch.dylib 0x13db0 _dispatch_root_queue_drain + 364
8 libdispatch.dylib 0x1454c _dispatch_worker_thread2 + 156
9 libsystem_pthread.dylib 0x9d0 _pthread_wqthread + 232
10 libsystem_pthread.dylib 0xaac start_wqthread + 8