KMM项目遇IncorrectDereferenceException错误，freeze方法无法使用求助

错误信息 #

Uncaught Kotlin exception: kotlin.native.IncorrectDereferenceException: illegal attempt to access non-shared dev.mrbe.haarShared.HaarSDK@abc468 from other thread
    at 0   kotlinmultiplatformsharedmodule     0x00000001020909a1 kfun:kotlin.Throwable#<init>(kotlin.String?){} + 97 (/opt/buildAgent/work/c5a36d4d82b914cf/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/Throwable.kt:24:56)
    at 1   kotlinmultiplatformsharedmodule     0x0000000102089dad kfun:kotlin.Exception#<init>(kotlin.String?){} + 93 (/opt/buildAgent/work/c5a36d4d82b914cf/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/Exceptions.kt:23:58)
    at 2   kotlinmultiplatformsharedmodule     0x0000000102089fcd kfun:kotlin.RuntimeException#<init>(kotlin.String?){} + 93 (/opt/buildAgent/work/c5a36d4d82b914cf/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/Exceptions.kt:34:58)
    at 3   kotlinmultiplatformsharedmodule     0x00000001020c140d kfun:kotlin.native.IncorrectDereferenceException#<init>(kotlin.String){} + 93 (/opt/buildAgent/work/c5a36d4d82b914cf/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/Runtime.kt:31:50)
    at 4   kotlinmultiplatformsharedmodule     0x00000001020c508f ThrowIllegalObjectSharingException + 623 (/opt/buildAgent/work/c5a36d4d82b914cf/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/concurrent/Internal.kt:115:11)
    at 5   kotlinmultiplatformsharedmodule     0x00000001022a1b52 _ZN12_GLOBAL__N_128throwIllegalSharingExceptionEP9ObjHeader + 34
    at 6   kotlinmultiplatformsharedmodule     0x00000001022a389d _ZN12_GLOBAL__N_136terminateWithIllegalSharingExceptionEP9ObjHeader + 13
    at 7   kotlinmultiplatformsharedmodule     0x00000001022a39b5 _ZNK27BackRefFromAssociatedObject3refIL11ErrorPolicy3EEEP9ObjHeaderv + 133
    at 8   kotlinmultiplatformsharedmodule     0x0000000102070e25 -[KotlinBase toKotlin:] + 21
    at 9   kotlinmultiplatformsharedmodule     0x0000000102295058 Kotlin_ObjCExport_refFromObjC + 88
    at 10  kotlinmultiplatformsharedmodule     0x0000000102040676 objc2kotlin.505 + 230
    at 11  haar                                0x00000001006b3181 $s4haar11MyViewModelC10addBooking7bookingySo031KotlinmultiplatformsharedmoduleF0C_tYaFTY0_ + 273 (/Users/essienedim/Desktop/HAAR /haar/haar/ContentView.swift:422:33)
    at 12  libswift_Concurrency.dylib          0x00007ff833c40426 _ZN5swift34runJobInEstablishedExecutorContextEPNS_3JobE + 310
    at 13  libswift_Concurrency.dylib          0x00007ff833c411bd _ZL17swift_job_runImplPN5swift3JobENS_11ExecutorRefE + 77
    at 14  libdispatch.dylib                   0x00000001014dfe77 _dispatch_continuation_pop + 87
    at 15  libdispatch.dylib                   0x00000001014def27 _dispatch_async_redirect_invoke + 997
    at 16  libdispatch.dylib                   0x00000001014f1e77 _dispatch_root_queue_drain + 414
    at 17  libdispatch.dylib                   0x00000001014f2b17 _dispatch_worker_thread2 + 278
    at 18  libsystem_pthread.dylib             0x00007ff833e39f8a _pthread_wqthread + 256
    at 19  libsystem_pthread.dylib             0x00007ff833e38f57 start_wqthread + 15
CoreSimulator 857.7 - Device: iPhone 14 Pro (C24AA3AD-B79D-437E-BCB7-A15C83C0F412) - Runtime: iOS 16.0 (20A360) - DeviceType: iPhone 14 Pro
(lldb) 

问题背景 #

刚接触KMM，项目持续抛出上述错误。尝试用freeze()方法解决，但提示Unresolved reference: freeze，不清楚操作有误还是不知道该冻结哪个对象。

相关代码 #

触发异常的Swift函数 #

func addBooking(booking: Booking) async {
    await sdk.postBooking(booking: booking)
}

ViewModel初始化（Swift） #

class MyViewModel: ObservableObject {
    let sdk: HaarSDK

    // ...

    init(sdk: HaarSDK) {
        self.sdk = sdk
        // ...
    }
}

主视图代码（Swift） #

struct MainView: View {
    
    @StateObject private var viewModel: MyViewModel
    
    init() {
        let sdk = HaarSDK(databaseDriverFactory: DatabaseDriverFactory())
        let viewModel = MyViewModel(sdk: sdk)
        _viewModel = StateObject(wrappedValue: viewModel)
    }

    // ...
}

Kotlin端SDK类 #

class HaarSDK(databaseDriverFactory: DatabaseDriverFactory) {
    private val database = Database(databaseDriverFactory)
    private val api = HaarApi()

    // ...

    @Throws(Exception::class)
    suspend fun postBooking(booking: Booking) {
        api.sendBooking(booking)
    }
    // ...
}

Kotlin端Database类 #

internal class Database(databaseDriverFactory: DatabaseDriverFactory) {
    private val database by lazy {
        AppDatabase(databaseDriverFactory.createDriver())
    }
    private val dbQuery = database.appDatabaseQueries
    // ...
}

Kotlin端API类 #

class HaarApi {
    private val httpClient = HttpClient {
        install(JsonFeature) {
            val json = Json { ignoreUnknownKeys = true }
            serializer = KotlinxSerializer(json)
        }
        // ...
    }

    suspend fun sendBooking(booking: Booking) {
        val response: HttpResponse = httpClient.post(BOOKING_ENDPOINT) {
            contentType(ContentType.Application.Json)
            body = booking
        }
        // ...
    }
}

解决方案 #

1. 解决freeze()未找到的问题 #

在Kotlin代码中导入对应包，才能使用该方法：

import kotlin.native.concurrent.freeze

2. 确定需要冻结的对象 #

错误信息明确指出是HaarSDK对象被跨线程访问导致的问题——SDK实例在主线程创建，却在Swift的async后台线程中被调用，而Kotlin Native默认禁止非共享对象跨线程访问。

3. 正确冻结对象的两种方式 #

方式一：在Kotlin端初始化时自动冻结

修改HaarSDK的构造函数，在初始化完成后冻结自身：

class HaarSDK(databaseDriverFactory: DatabaseDriverFactory) {
    private val database = Database(databaseDriverFactory)
    private val api = HaarApi()

    init {
        freeze()
    }

    // ... 原有方法
}

注意：确保database和api对象本身也是线程安全的，或者也被冻结。如果Database或HaarApi内部有可变状态，需要额外处理线程安全。

方式二：在Swift端创建实例时冻结

在Swift中创建HaarSDK实例后，调用其freeze()方法（KMM生成的类默认继承KotlinBase，支持该方法）：

init() {
    let sdk = HaarSDK(databaseDriverFactory: DatabaseDriverFactory())
    sdk.freeze() // 新增冻结调用
    let viewModel = MyViewModel(sdk: sdk)
    _viewModel = StateObject(wrappedValue: viewModel)
}

4. 更优雅的线程安全方案（推荐） #

如果不想用freeze()（冻结后对象状态不可变），可以通过协程调度确保suspend函数在合适的线程执行：
修改Kotlin端的postBooking方法，指定调度器：

import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.withContext

@Throws(Exception::class)
suspend fun postBooking(booking: Booking) {
    withContext(Dispatchers.Default) {
        api.sendBooking(booking)
    }
}

同时确保HttpClient和数据库操作本身是线程安全的（HttpClient默认是线程安全的，数据库驱动需确认支持多线程访问）。

内容的提问来源于stack exchange，提问作者MrBE