Generate initRuntimeIfNeeded() at the beginning of staticCFunction

#KT-44283 Fixed

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/CodeGenerator.kt

@@ -128,13 +128,22 @@ internal inline fun<R> generateFunction(codegen: CodeGenerator,
                                         code: FunctionGenerationContext.(FunctionGenerationContext) -> R) {
     val llvmFunction = codegen.llvmFunction(function)
 
+    val isCToKotlinBridge = function.origin == CBridgeOrigin.C_TO_KOTLIN_BRIDGE
+
     val functionGenerationContext = FunctionGenerationContext(
             llvmFunction,
             codegen,
             startLocation,
             endLocation,
-            switchToRunnable = function.origin == CBridgeOrigin.C_TO_KOTLIN_BRIDGE,
+            switchToRunnable = isCToKotlinBridge,
             function)
+
+    if (isCToKotlinBridge) {
+        // Enable initRuntimeIfNeeded for legacy MM too:
+        functionGenerationContext.needsRuntimeInit = true
+        // This fixes https://youtrack.jetbrains.com/issue/KT-44283.
+    }
+
     try {
         generateFunctionBody(functionGenerationContext, code)
     } finally {

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

@@ -3806,6 +3806,10 @@ createInterop("kt43265") {
     it.defFile 'interop/kt43265/kt43265.def'
 }
 
+createInterop("kt44283") {
+    it.defFile 'interop/kt44283/kt44283.def'
+}
+
 createInterop("kt43502") {
     it.defFile 'interop/kt43502/kt43502.def'
     it.headers "$projectDir/interop/kt43502/kt43502.h"
@@ -4190,6 +4194,14 @@ interopTest("interop_kt43265") {
     source = "interop/kt43265/usage.kt"
 }
 
+interopTest("interop_kt44283") {
+    disabled = (project.testTarget == 'wasm32') || // No interop for wasm yet.
+            project.globalTestArgs.contains('-opt') // Incompatible with -g.
+    flags = ['-g']
+    interop = 'kt44283'
+    source = "interop/kt44283/main.kt"
+}
+
 dynamicTest("interop_kt43502") {
     disabled = (project.target.name != project.hostName)
     interop = "kt43502"

kotlin-native/backend.native/tests/interop/kt44283/kt44283.def

@@ -0,0 +1,25 @@
+---
+#include <stdlib.h>
+#include <pthread.h>
+
+typedef struct {
+    int d;
+} TestStruct;
+
+typedef struct {
+    void (*f)(TestStruct data);
+} ThreadData;
+
+void *dispatch(void *rawArg) {
+    ThreadData *arg = rawArg;
+    arg->f((TestStruct) {.d = 1});
+    return NULL;
+}
+
+void invokeFromThread(void (*f)(TestStruct data)) {
+    pthread_t thread_id;
+    ThreadData *threadData = malloc(sizeof(ThreadData));
+    threadData->f = f;
+    pthread_create(&thread_id, NULL, dispatch, (void *) threadData);
+    pthread_join(thread_id, NULL);
+}

kotlin-native/backend.native/tests/interop/kt44283/main.kt

@@ -0,0 +1,21 @@
+import kotlinx.cinterop.*
+import kt44283.*
+import kotlin.native.concurrent.AtomicInt
+import kotlin.test.*
+
+val callbackCounter = AtomicInt(0)
+
+fun main() {
+    val func = staticCFunction<CValue<TestStruct>, Unit> {
+        kotlin.native.internal.GC.collect() // Helps to ensure that "runtime" is already initialized.
+
+        memScoped {
+            println("Hello, Kotlin/Native! ${it.ptr.pointed.d}")
+        }
+        callbackCounter.increment()
+    }
+
+    assertEquals(0, callbackCounter.value)
+    invokeFromThread(func.reinterpret())
+    assertEquals(1, callbackCounter.value)
+}