Hi guys I have a problem on Ktor client native I ve been str

Question

Hi guys I have a problem on Ktor client native I ve been struggling to make the code below works after migrating kotlin to 1 4 0 version while migrating I changed coroutine version to `1 3 9 native mt` ```class TestFreezingViewModel val client HttpClient fun call CoroutineScope Dispatchers Main launch start = CoroutineStart LAZY try client get lt String gt <https test com> catch e Throwable e printStackTrace start swift side code TestFreezingViewModel call ``` while the code running The error on the slack thread occurs when Coroutine s `invokeOnCompletion` is invoked freeze is called and it tells that `HttpClient` can t be frozen When I checked the source code HttpClient init calls `preventFreeze ` I would like to know the intention of `preventFreeze` and what is the proper approach to use on developer s side Is there some advice

Hyun · Answer

```kotlin native concurrent FreezingException freezing of InvokeOnCompletion InvokeOnCompletion 1b76e08 has failed first blocker is HttpClient io ktor client engine ios IosClientEngine 1b1b748 at 0 kotlinIOS 0x000000010bf93fed kfun kotlin Throwable lt init gt kotlin String + 93 at 1 kotlinIOS 0x000000010bf8cb9b kfun kotlin Exception lt init gt kotlin String + 91 at 2 kotlinIOS 0x000000010bf8cdeb kfun kotlin RuntimeException lt init gt kotlin String + 91 at 3 kotlinIOS 0x000000010bfc2c13 kfun kotlin native concurrent FreezingException lt init gt kotlin Any kotlin Any + 643 at 4 kotlinIOS 0x000000010bfc4297 ThrowFreezingException + 231 at 5 kotlinIOS 0x000000010c0b2f4f FreezeSubgraph + 2815 at 6 kotlinIOS 0x000000010c0cc17b Kotlin Worker freezeInternal + 27 at 7 kotlinIOS 0x000000010bfc2d3e kfun kotlin native concurrent freeze 0 0 0 lt kotlin Any gt 0 0 + 62 at 8 kotlinIOS 0x000000010c10c749 kfun kotlinx coroutines JobSupport invokeOnCompletion kotlin Boolean kotlin Boolean kotlin Function1 lt kotlin Throwable kotlin Unit gt kotlinx coroutines DisposableHandle + 1881 at 9 kotlinIOS 0x000000010c10bf76 kfun kotlinx coroutines JobSupport invokeOnCompletion kotlin Function1 lt kotlin Throwable kotlin Unit gt kotlinx coroutines DisposableHandle + 198 at 10 kotlinIOS 0x000000010c33b15b kfun io ktor client engine createCallContext io ktor client engine HttpClientEngine kotlinx coroutines Job kotlin coroutines CoroutineContext + 1451 at 11 kotlinIOS 0x000000010c302d08 kfun io ktor client engine HttpClientEngine $executeWithinCallContextCOROUTINE$9 invokeSuspend internal + 1048 at 12 kotlinIOS 0x000000010c303444 kfun io ktor client engine HttpClientEngine executeWithinCallContext internal + 308 at 13 kotlinIOS 0x000000010c30420a kfun io ktor client engine HttpClientEngine $install$lambda 0COROUTINE$10 invokeSuspend internal + 1562 at 14 kotlinIOS 0x000000010c304bf8 kfun io ktor client engine HttpClientEngine $install$lambda 0COROUTINE$10 invoke internal + 312 at 15 kotlinIOS 0x000000010c29da5f kfun io ktor util pipeline SuspendFunctionGun loop internal + 1135 at 16 kotlinIOS 0x000000010c29d0ab kfun io ktor util pipeline SuspendFunctionGun proceed internal + 395 at 17 kotlinIOS 0x000000010c29d50a kfun io ktor util pipeline SuspendFunctionGun execute internal + 474 at 18 kotlinIOS 0x000000010c295759 kfun io ktor util pipeline Pipeline execute 1 1 1 0 1 0 + 361 at 19 kotlinIOS 0x000000010c326be5 kfun io ktor client features HttpSend DefaultSender $executeCOROUTINE$27 invokeSuspend internal + 1365 at 20 kotlinIOS 0x000000010c327244 kfun io ktor client features HttpSend DefaultSender execute internal + 308 at 21 kotlinIOS 0x000000010c324fbc kfun io ktor client features HttpSend Feature $install$lambda 0COROUTINE$26 invokeSuspend internal + 2236 at 22 kotlinIOS 0x000000010c3260f8 kfun io ktor client features HttpSend Feature $install$lambda 0COROUTINE$26 invoke internal + 312 at 23 kotlinIOS 0x000000010c29da5f kfun io ktor util pipeline SuspendFunctionGun loop internal + 1135 at 24 kotlinIOS 0x000000010c29d0ab kfun io ktor util pipeline SuspendFunctionGun proceed internal + 395 at 25 kotlinIOS 0x000000010c29d2a5 kfun io ktor util pipeline SuspendFunctionGun proceedWith internal + 213 at 26 kotlinIOS 0x000000010c3173eb kfun io ktor client features HttpCallValidator Companion $install$lambda 0COROUTINE$17 invokeSuspend internal + 907 at 27 kotlinIOS 0x000000010c317c58 kfun io ktor client features HttpCallValidator Companion $install$lambda 0COROUTINE$17 invoke internal + 312 at 28 kotlinIOS 0x000000010c29da5f kfun io ktor util pipeline SuspendFunctionGun loop internal + 1135 at 29 kotlinIOS 0x000000010c29d0ab kfun io ktor util pipeline SuspendFunctionGun proceed internal + 395```

Hyun · Answer

reported on youtrack <https youtrack jetbrains com issue KTOR 973>