[K/N] Stdlib: warnings as errors

Fix or suppress warnings in Native stdlib.

kotlin-native/runtime/src/main/kotlin/kotlin/native/concurrent/Future.kt

@@ -26,7 +26,7 @@ enum class FutureState(val value: Int) {
  * Class representing abstract computation, whose result may become available in the future.
  */
 @Suppress("NON_PUBLIC_PRIMARY_CONSTRUCTOR_OF_INLINE_CLASS")
-public inline class Future<T> @PublishedApi internal constructor(val id: Int) {
+public value class Future<T> @PublishedApi internal constructor(val id: Int) {
     /**
      * Blocks execution until the future is ready.
      *

kotlin-native/runtime/src/main/kotlin/kotlin/native/concurrent/Worker.kt

@@ -27,7 +27,7 @@ import kotlinx.cinterop.*
  * Class representing worker.
  */
 @Suppress("NON_PUBLIC_PRIMARY_CONSTRUCTOR_OF_INLINE_CLASS")
-public inline class Worker @PublishedApi internal constructor(val id: Int) {
+public value class Worker @PublishedApi internal constructor(val id: Int) {
     companion object {
         /**
          * Start new scheduling primitive, such as thread, to accept new tasks via `execute` interface.

kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/KClassImpl.kt

@@ -12,6 +12,7 @@ internal class KClassImpl<T : Any>(private val typeInfo: NativePtr) : KClass<T>
 
     @ExportForCompiler
     @ConstantConstructorIntrinsic("KCLASS_IMPL")
+    @Suppress("UNREACHABLE_CODE")
     constructor() : this(TODO("This is intrinsic constructor and it shouldn't be used directly"))
 
     // TODO: consider replacing '$' by another delimeter that can't be used in class name specified with backticks (``)

kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/KTypeImpl.kt

@@ -57,6 +57,7 @@ internal class KTypeImpl<T>(
 
     @ExportForCompiler
     @ConstantConstructorIntrinsic("KTYPE_IMPL")
+    @Suppress("UNREACHABLE_CODE")
     constructor() : this(null, TODO("This is intrinsic constructor and it shouldn't be used directly"), false)
 
     override fun equals(other: Any?) =

kotlin-native/runtime/src/main/kotlin/kotlin/native/internal/test/GTestLogger.kt

@@ -8,7 +8,7 @@ package kotlin.native.internal.test
 internal class GTestLogger : TestLoggerWithStatistics() {
 
     private val Collection<TestSuite>.totalTestsNotIgnored: Int
-        get() = asSequence().filter { !it.ignored }.sumBy { it.testCases.values.count { !it.ignored } }
+        get() = asSequence().filter { !it.ignored }.sumOf { it.testCases.values.count { !it.ignored } }
 
     private val Collection<TestSuite>.totalNotIgnored: Int
         get() = filter { !it.ignored }.size