Crash in Testflight builds when accessing @Dependency / Linking issue?

[Lischen]

Description

Our App is quite modularised and most sub features are in its own package.

I noticed that in those few features the app crashes as soon as it accesses @dependency. I have tried commenting out piece by piece and when all @Dependecy references are removed it stops crashing. If I do an action like tap close, which is done via the Dependecy macro, it crashes. The dependencies are definitely set.

We think it is broken since 1.16

Checklist

• I have determined whether this bug is also reproducible in a vanilla SwiftUI project.
• If possible, I've reproduced the issue using the main branch of this package.
• This issue hasn't been addressed in an existing GitHub issue or discussion.

Expected behavior

I expect it not to crash

Actual behavior

0  libswiftCore.dylib             0x17c998 KeyPath._projectReadOnly(from:) + 80
1  libswiftCore.dylib             0x1819ec swift_getAtKeyPath + 24
2  App                                   0x96e6f4 closure #1 in Dependency._wrappedValue.getter + 212 (Dependency.swift:212)
3  App                                   0x96e984 partial apply for closure #1 in Dependency._wrappedValue.getter + 4313803140 (<compiler-generated>:4313803140)
4  libswift_Concurrency.dylib     0x34368 TaskLocal.withValue<A>(_:operation:file:line:) + 232
5  App                                   0x96e420 Dependency._wrappedValue.getter + 211 (Dependency.swift:211)
6  App                                   0x4c144 closure #2 in EditTeamNameFeature.body.getter + 94 (EditTeamNameFeature.swift:94)
7  App                                   0x4e50c specialized Reducer<>.reduce(into:action:) + 8 (@__swiftmacro_4Team04EditA11NameFeatureV5StateV03setA6Detail011ObservationE7TrackedfMa_.swift:8)
8  App                                   0x4d7ec protocol witness for Reducer.reduce(into:action:) in conformance EditTeamNameFeature + 4304230380 (<compiler-generated>:4304230380)
9  App                                   0x8815c4 partial apply for closure #2 in _DependencyKeyWritingReducer.reduce(into:action:) + 171 (DependencyKeyWritingReducer.swift:171)
10 App                                   0x99cbbc closure #1 in closure #1 in closure #1 in withDependencies<A>(_:operation:) + 49 (WithDependencies.swift:49)
11 App                                   0x9a1438 partial apply for closure #1 in closure #1 in withDependencies<A>(_:operation:) + 48 (WithDependencies.swift:48)
12 libswift_Concurrency.dylib     0x34368 TaskLocal.withValue<A>(_:operation:file:line:) + 232
13 App                                   0x99cb28 closure #1 in withDependencies<A>(_:operation:) + 47 (WithDependencies.swift:47)
14 App                                   0x99c468 withDependencies<A>(_:operation:) + 44 (WithDependencies.swift:44)
15 App                                   0x881538 _DependencyKeyWritingReducer.reduce(into:action:) + 173 (DependencyKeyWritingReducer.swift:173)
16 App                                   0x8aec44 open #1 <A, B, C>(reducer:) in RootStore.send(_:originatingFrom:) + 54 (RootStore.swift:54)
17 App                                   0x8ae6b0 RootStore.send(_:originatingFrom:) + 151 (RootStore.swift:151)
18 App                                   0x8b8850 specialized Store.send(_:originatingFrom:) + 379 (Store.swift:379)
19 App                                   0x5ddf8 closure #3 in closure #1 in EditTeamNameView.body.getter + 58 (EditTeamNameView.swift:58)
20 libswift_Concurrency.dylib     0x60f5c swift::runJobInEstablishedExecutorContext(swift::Job*) + 252
21 libswift_Concurrency.dylib     0x62514 swift_job_runImpl(swift::Job*, swift::SerialExecutorRef) + 144
22 libdispatch.dylib              0x12948 _dispatch_main_queue_drain + 748
23 libdispatch.dylib              0x1264c _dispatch_main_queue_callback_4CF + 44
24 CoreFoundation                 0x79bbc __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 16
25 CoreFoundation                 0x761b0 __CFRunLoopRun + 1996
26 CoreFoundation                 0xc8274 CFRunLoopRunSpecific + 588
27 GraphicsServices               0x14c0 GSEventRunModal + 164
28 UIKitCore                      0x3ee77c -[UIApplication _run] + 816
29 UIKitCore                      0x14e64 UIApplicationMain + 340
30 PhotoRoom                      0x1d108 main + 92 (AppDelegate.swift:92)
31 ???                            0x1c5d24de8 (Missing)

Reproducing project

The bug is just happening when being built via TestFlight. All crashes are Testflight builds.

I noticed that in those few features the app crashes as soon as it accesses @dependency. I have tried commenting out piece by piece and when all @Dependecy references are removed it stops crashing. If I do an action like tap close, which is done via a dependency, it crashes.

I understand that this could very well be an XCode linking issue and that it is suboptimal to not give a way to reproduce.

I tried several things:

• objC linker flag
• revert to XCode 16 and build the app with that
• move Dependency declarations around

All without luck.

I posted an small version of the breaking feature below. onAppear is being called in the view in onAppear. I tried different Dependencies and clients, including setting the dependency at initialisation of the view etc.
I tried removing onAppear, but at any point I call a dependency, it crashes.
Can anyone help?

import ComposableArchitecture

@Reducer
struct EditTeamNameFeature {
    @ObservableState
    struct State: Equatable {
        // stuff
    }

    enum Action: Equatable {
        case onAppear
        // stuff
    }

    @Dependency(Client.self) var analyticsClient

    var body: some ReducerOf<Self> {
        
        Reduce<State, Action> { state, action in
            switch action {
            case .onAppear:
                analyticsClient.opened()
                return .none
                // more actions
            }
        }
    }
}

import ComposableArchitecture

@DependencyClient
struct Client {
    var opened: () -> Void
}

// MARK: DependencyKey

extension Client: DependencyKey {
    static var liveValue: Self {
        Self(
            opened: // tracking
        )
    }

    static var previewValue: Self {
        Self(
            opened: { }
        )
    }

    static let testValue = Self()
}

The Composable Architecture version information

1.17.1

Destination operating system

iOS 18

Xcode version information

16.2

Swift Compiler version information

1.115.1 Apple Swift version 6.0.3 (swiftlang-6.0.3.1.10 clang-1600.0.30.1)

[mbrandonw]

Hi @Lischen, it isn't likely this is a problem with the library, and instead a problem of how your project is configured. Are you sure it really only happens with Test Flight builds? Or is it more of a problem with release builds? Have you tried reproducing the problem when building locally for release? And if you reproduce it can you provide a minimal project that does so for us to look at.

Since I don't think this is an issue with the library I am going to convert it to a discussion. Please feel free to continue the conversation over there!