Restore runtimeState value in deinitRuntime (#4587)

kotlin-native/backend.native/tests/build.gradle

@@ -3813,6 +3813,10 @@ if (PlatformInfo.isAppleTarget(project)) {
     createInterop("objcKt43517") {
         it.defFile 'framework/kt43517/kt43517.def'
     }
+    createInterop("objc_kt42172") {
+        it.defFile 'interop/objc/kt42172/objclib.def'
+        it.headers "$projectDir/interop/objc/kt42172/objclib.h"
+    }
 }
 
 createInterop("withSpaces") {
@@ -4281,6 +4285,25 @@ if (PlatformInfo.isAppleTarget(project)) {
                 it.contains("isObjectAliveShouldCrash")  // And should contain stack trace.
         }
     }
+
+    interopTest("interop_objc_kt42172") {
+        source = "interop/objc/kt42172/main.kt"
+        interop = "objc_kt42172"
+        flags = ['-Xopt-in=kotlin.native.internal.InternalForKotlinNative']
+        goldValue = 'Executed finalizer\n'
+
+        doBeforeBuild {
+            mkdir(buildDir)
+            execKonanClang(project.target) {
+                args "$projectDir/interop/objc/kt42172/objclib.m"
+                args "-lobjc", '-fobjc-arc'
+                args '-fPIC', '-shared', '-o', "$buildDir/libobjc_kt42172.dylib"
+            }
+            if (project.target instanceof KonanTarget.IOS_X64) {
+                UtilsKt.codesign(project, "$buildDir/libobjc_kt42172.dylib")
+            }
+        }
+    }
 }
 
 standaloneTest("jsinterop_math") {

kotlin-native/backend.native/tests/interop/objc/kt42172/main.kt

@@ -0,0 +1,18 @@
+import objclib.*
+import kotlin.native.concurrent.*
+import kotlinx.cinterop.*
+
+fun main() {
+    val worker = Worker.start()
+    worker.execute(TransferMode.SAFE, {}) {
+        val withFinalizer = WithFinalizer()
+        val finalizer: Finalizer = staticCFunction { ptr: COpaquePointer? ->
+            ptr?.asStableRef<Any>()?.dispose()
+            println("Executed finalizer")
+        }
+        val arg = StableRef.create(Any()).asCPointer()
+        withFinalizer.setFinalizer(finalizer, arg)
+    }.result
+    worker.requestTermination().result
+    waitWorkerTermination(worker)
+}

kotlin-native/backend.native/tests/interop/objc/kt42172/objclib.def

@@ -0,0 +1,3 @@
+language = Objective-C
+headerFilter = **/objclib.h
+linkerOpts = -lobjc_kt42172

kotlin-native/backend.native/tests/interop/objc/kt42172/objclib.h

@@ -0,0 +1,9 @@
+#import <objc/NSObject.h>
+
+typedef void (*Finalizer)(void*);
+
+@interface WithFinalizer : NSObject
+
+- (void)setFinalizer:(Finalizer)finalizer arg:(void*)arg;
+
+@end

kotlin-native/backend.native/tests/interop/objc/kt42172/objclib.m

@@ -0,0 +1,19 @@
+#include "objclib.h"
+
+@implementation WithFinalizer {
+    Finalizer finalizer_;
+    void* arg_;
+}
+
+- (void)dealloc {
+    if (finalizer_) {
+        finalizer_(arg_);
+    }
+}
+
+- (void)setFinalizer:(Finalizer)finalizer arg:(void*)arg {
+    finalizer_ = finalizer;
+    arg_ = arg;
+}
+
+@end

kotlin-native/runtime/src/main/cpp/Runtime.cpp

@@ -140,7 +140,9 @@ RuntimeState* initRuntime() {
 void deinitRuntime(RuntimeState* state, bool destroyRuntime) {
   RuntimeAssert(state->status == RuntimeStatus::kRunning, "Runtime must be in the running state");
   state->status = RuntimeStatus::kDestroying;
-  // This may be called after TLS is zeroed out, so ::memoryState in Memory cannot be trusted.
+  // This may be called after TLS is zeroed out, so ::runtimeState and ::memoryState in Memory cannot be trusted.
+  // TODO: This may in fact reallocate TLS without guarantees that it'll be deallocated again.
+  ::runtimeState = state;
   RestoreMemory(state->memoryState);
   bool lastRuntime = atomicAdd(&aliveRuntimesCount, -1) == 0;
   switch (Kotlin_getDestroyRuntimeMode()) {
@@ -159,6 +161,7 @@ void deinitRuntime(RuntimeState* state, bool destroyRuntime) {
   DeinitMemory(state->memoryState, destroyRuntime);
   konanDestructInstance(state);
   WorkerDestroyThreadDataIfNeeded(workerId);
+  ::runtimeState = kInvalidRuntime;
 }
 
 void Kotlin_deinitRuntimeCallback(void* argument) {
@@ -191,7 +194,6 @@ void Kotlin_initRuntimeIfNeeded() {
 void Kotlin_deinitRuntimeIfNeeded() {
   if (isValidRuntime()) {
     deinitRuntime(::runtimeState, false);
-    ::runtimeState = kInvalidRuntime;
   }
 }
 
@@ -249,7 +251,6 @@ void Kotlin_shutdownRuntime() {
     }
 
     deinitRuntime(runtime, canDestroyRuntime);
-    ::runtimeState = kInvalidRuntime;
 }
 
 KInt Konan_Platform_canAccessUnaligned() {