Hello, I have this following test that passes in a...

# multiplatform

[Saud Khan]

Hello, I have this following test that passes in all other platforms but iosSimulatorArm64 and macosArm64 but passes on jvm, iosX64 and macosX64. Is this a known issue? I didn't see any related tickets

CastTest.kt.cpp

[Chris Lee]

What is the issue? There’s no error / output / stack trace provided.

[Saud Khan]

oh sorry... looks like the error didn't post. trying again

[Saud Khan]

Instead of throwing the ClassCastException those two platforms are actually returning the instance as if it can be casted. So actually the assertion fails because it is not null.

kotlin.AssertionError: Expected an exception of kotlin.ClassCastException to be thrown, but was kotlin.AssertionError: Expected value to be null, but was: <CastTest.Motorcycle@54e4070>.
	at kotlin.Error#<init>(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/Exceptions.kt:14)
	at kotlin.AssertionError#<init>(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/Exceptions.kt:134)
	at kotlin.test.DefaultAsserter#fail(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/DefaultAsserter.kt:21)
	at kotlin.test.Asserter#fail(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/Assertions.kt:643)
	at kotlin.test#checkResultIsFailure(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/test/Assertions.kt:36)
	at <global>.CastTest#should(/Users/saud.khan/playground/castTest/src/commonTest/kotlin/CastTest.kt:42)
	at $CastTest$test$0.$should(/Users/saud.khan/playground/castTest/src/commonTest/kotlin/CastTest.kt:34)
	at $CastTest$test$0.$should(/Users/saud.khan/playground/castTest/src/commonTest/kotlin/CastTest.kt:34)
	at kotlin.Function1#invoke(/Users/teamcity/.gradle/daemon/8.4/[K][Suspend]Functions:1)
	at kotlin.native.internal.test.BaseClassSuite.TestCase#doRun(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/TestSuite.kt:177)
	at kotlin.native.internal.test.TestCase#doRun(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/TestSuite.kt:44)
	at kotlin.native.internal.test.TestCase#run(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/TestSuite.kt:52)
	at kotlin.native.internal.test.TestCase#run(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/TestSuite.kt:49)
	at kotlin.native.internal.test.TestRunner.run#internal(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/TestRunner.kt:263)
	at kotlin.native.internal.test.TestRunner.runIteration#internal(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/TestRunner.kt:289)
	at kotlin.native.internal.test.TestRunner#run(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/TestRunner.kt:304)
	at kotlin.native.internal.test#testLauncherEntryPoint(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/Launcher.kt:33)
	at kotlin.native.internal.test#main(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/Launcher.kt:38)
	at <global>.Konan_start(/Users/saud.khan/.gradle/daemon/8.8/entryPointOwner:1)
	at <global>.Init_and_run_start(Unknown Source)
	at <global>.0x0(Unknown Source)
	at <global>.0x0(Unknown Source)
	at <global>.0x0(Unknown Source)
	at kotlin.Error#<init>(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/Exceptions.kt:14)
	at kotlin.AssertionError#<init>(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/kotlin-native/runtime/src/main/kotlin/kotlin/Exceptions.kt:132)
	at kotlin.test.DefaultAsserter#fail(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/DefaultAsserter.kt:16)
	at kotlin.test.Asserter#fail(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/Assertions.kt:634)
	at kotlin.test.Asserter#assertTrue(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/Assertions.kt:652)
	at kotlin.test.Asserter#assertTrue(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/Assertions.kt:650)
	at kotlin.test.Asserter#assertNull(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/Assertions.kt:707)
	at kotlin.test.Asserter#assertNull(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/Assertions.kt:706)
	at kotlin.test#assertNull(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/Assertions.kt:159)
	at kotlin.test#assertNull$default(/opt/buildAgent/work/b2e1db4d8d903ca4/kotlin/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/Assertions.kt:158)
	at <global>.CastTest#should(/Users/saud.khan/playground/castTest/src/commonTest/kotlin/CastTest.kt:41)
	at $CastTest$test$0.$should(/Users/saud.khan/playground/castTest/src/commonTest/kotlin/CastTest.kt:34)

Even making the cast function inline fails the same way.

but it doesn't do that if we replace the cast function to directly cast instead:

val hasDoors: HasDoors = motorcycle as HasDoors

[Saud Khan]

Also forgot to add that it happens on both Kotlin 2.0 and 1.9.23

[Saud Khan]

Looks like it is impacting all natives and only if we use a generic cast function. Added a ticket: https://youtrack.jetbrains.com/issue/KT-69675/Native-builds-does-not-throw-ClassCastException