native-mt: MutableStateFlow cannot be frozen

[Thomas-Vos]

Version: 1.3.7-native-mt-1.4-M2

When freezing MutableStateFlow and changing the value like this:

import kotlinx.coroutines.flow.MutableStateFlow
import kotlin.native.concurrent.freeze

fun freezeExample() {
    val stateFlow = MutableStateFlow(0)
    stateFlow.freeze()
    stateFlow.value = 1
}

The following exception is thrown:

Uncaught Kotlin exception: kotlin.native.concurrent.InvalidMutabilityException: mutation attempt of frozen kotlinx.coroutines.flow.StateFlowImpl@805b40c8
    at 0   common                              0x00000001074f6860 kfun:kotlin.Throwable#<init>(kotlin.String?){} + 92
    at 1   common                              0x00000001074ef9c0 kfun:kotlin.Exception#<init>(kotlin.String?){} + 88
    at 2   common                              0x00000001074ef3fc kfun:kotlin.RuntimeException#<init>(kotlin.String?){} + 88
    at 3   common                              0x00000001075237b4 kfun:kotlin.native.concurrent.InvalidMutabilityException#<init>(kotlin.String){} + 88
    at 4   common                              0x0000000107524bc0 ThrowInvalidMutabilityException + 468
    at 5   common                              0x00000001088a3f60 MutationCheck + 132
    at 6   common                              0x0000000107637d60 kfun:kotlinx.coroutines.flow.StateFlowImpl.<set-sequence>#internal + 92
    at 7   common                              0x00000001076385f4 kfun:kotlinx.coroutines.flow.StateFlowImpl.<set-value>#internal + 900
    at 8   common                              0x00000001082aa324 kfun:com.superthomaslab.hueessentials.common#freezeExample(){} + 288
    at 9   common                              0x0000000108863b84 objc2kotlin.24665 + 96
    at 10  HueEssentials-dev                   0x00000001047e0858 $s17HueEssentials_dev11AppDelegateC11application_29didFinishLaunchingWithOptionsSbSo13UIApplicationC_SDySo0l6LaunchK3KeyaypGSgtFTo + 232
    at 11  UIKitCore                           0x000000018705b988 32D99ABD-E47B-38D8-BBD1-68AEA293A9A6 + 10901896
    at 12  UIKitCore                           0x000000018705d768 32D99ABD-E47B-38D8-BBD1-68AEA293A9A6 + 10909544
    at 13  UIKitCore                           0x0000000187063164 32D99ABD-E47B-38D8-BBD1-68AEA293A9A6 + 10932580
    at 14  UIKitCore                           0x00000001867d307c 32D99ABD-E47B-38D8-BBD1-68AEA293A9A6 + 1953916
    at 15  UIKitCore                           0x000000018705f178 32D99ABD-E47B-38D8-BBD1-68AEA293A9A6 + 10916216
    at 16  UIKitCore                           0x000000018705f4d4 32D99ABD-E47B-38D8-BBD1-68AEA293A9A6 + 10917076
    at 17  UIKitCore                           0x0000000187065358 UIApplicationMain + 1944
    at 18  HueEssentials-dev                   0x00000001047e1aac main + 80
    at 19  libdyld.dylib                       0x0000000182d0d2dc 322C4E05-D0CF-33F5-B996-CE5C67DF59B6 + 4828

[qwwdfsad]

Fixed in 1.3.9-native-mt-2

[Thomas-Vos]

@qwwdfsad could you reopen this issue, please? Unfortunately MutableStateFlow no longer works with 1.4.1-native-mt.

Uncaught Kotlin exception: kotlin.native.concurrent.InvalidMutabilityException: mutation attempt of frozen kotlinx.coroutines.flow.StateFlowImpl@82e51d08
    at 0   common                              0x0000000105a04d8c kfun:kotlin.Throwable#<init>(kotlin.String?){} + 96
    at 1   common                              0x00000001059fd158 kfun:kotlin.Exception#<init>(kotlin.String?){} + 92
    at 2   common                              0x00000001059fd3c8 kfun:kotlin.RuntimeException#<init>(kotlin.String?){} + 92
    at 3   common                              0x0000000105a32cb4 kfun:kotlin.native.concurrent.InvalidMutabilityException#<init>(kotlin.String){} + 92
    at 4   common                              0x0000000105a3407c ThrowInvalidMutabilityException + 336
    at 5   common                              0x0000000107018cdc MutationCheck + 156
    at 6   common                              0x0000000105b5273c kfun:kotlinx.coroutines.flow.StateFlowImpl.<set-sequence>#internal + 96
    at 7   common                              0x0000000105b53050 kfun:kotlinx.coroutines.flow.StateFlowImpl.updateState#internal + 948
    at 8   common                              0x0000000105b52a48 kfun:kotlinx.coroutines.flow.StateFlowImpl.<set-value>#internal + 248
    at 9   common                              0x0000000105e89ed8 kfun:com.superthomaslab.hueessentials.common#freezeExample(){} + 292
    at 10  common                              0x0000000106fcbf84 objc2kotlin.26222 + 100
    at 11  HueEssentials-dev                   0x0000000102987e0c $s17HueEssentials_dev11AppDelegateC11application_29didFinishLaunchingWithOptionsSbSo13UIApplicationC_SDySo0l6LaunchK3KeyaypGSgtFTo + 212
    at 12  UIKitCore                           0x00000001a16a2540 05147936-B875-3EF3-94DB-9C8869BB0E34 + 12334400
    at 13  UIKitCore                           0x00000001a16a45a8 05147936-B875-3EF3-94DB-9C8869BB0E34 + 12342696
    at 14  UIKitCore                           0x00000001a16aa004 05147936-B875-3EF3-94DB-9C8869BB0E34 + 12365828
    at 15  UIKitCore                           0x00000001a0d01950 05147936-B875-3EF3-94DB-9C8869BB0E34 + 2238800
    at 16  UIKitCore                           0x00000001a16a5db0 05147936-B875-3EF3-94DB-9C8869BB0E34 + 12348848
    at 17  UIKitCore                           0x00000001a16a61dc 05147936-B875-3EF3-94DB-9C8869BB0E34 + 12349916
    at 18  UIKitCore                           0x00000001a16aba74 UIApplicationMain + 168
    at 19  HueEssentials-dev                   0x0000000102988e58 main + 88
    at 20  libdyld.dylib                       0x000000019e92d6c0 BA60CB9E-95C5-3646-BEED-D313E15586CF + 5824

[Thomas-Vos]

Looks like the StateFlow tests were disabled for 1.4.1-native-mt:

kotlinx.coroutines/kotlinx-coroutines-core/native/test/FreezingTest.kt

Lines 55 to 75 in c70bc3e

	// @Test
	// fun testStateFlowValue() = runTest {
	// val stateFlow = MutableStateFlow(0)
	// stateFlow.freeze()
	// stateFlow.value = 1
	// }
	//
	// @Test
	// @OptIn(ExperimentalStdlibApi::class)
	// fun testStateFlowCollector() = runTest {
	// val stateFlow = MutableStateFlow(0)
	// stateFlow.freeze()
	// repeat(10) {
	// launch {
	// stateFlow.collect {
	// if (it == 42) cancel()
	// }
	// }
	// }
	// stateFlow.value = 42
	// }

[qwwdfsad]

Fixed in 1.4.2-native-mt

[xiaobailong24]

1.5.1-native-mt got same error
touchlab/Stately#71

[sergeych]

Still not working. Why creating another single-thread-only lang? There are way too much already. Looks pathetic, all these shamanic dances just to prevent qualified developers to to their work... because some abstract idea from the world of dreams and illusions ;) We just will drop kotlin.native as yet another epic fail. A good idea burried by incompetent system architect ;)

[LouisCAD]

@sergeych Enable the new memory model from Kotlin 1.6, use the non native-mt 1.6.0 kotlinx.coroutines version, and voilà, you have a fully multi-threaded Kotlin/Native 😝