Fix #2872 (#2898)

backend.native/tests/interop/objc/smoke.kt

@@ -23,6 +23,7 @@ fun run() {
     testCustomRetain()
     testVarargs()
     testOverrideInit()
+    testMultipleInheritanceClash()
 
     assertEquals(2, ForwardDeclaredEnum.TWO.value)
 
@@ -310,6 +311,21 @@ class TestOverrideInitImpl @OverrideInit constructor(val value: Int) : TestOverr
 
 private class MyException : Throwable()
 
+fun testMultipleInheritanceClash() {
+    val clash1 = MultipleInheritanceClash1()
+    val clash2 = MultipleInheritanceClash2()
+
+    clash1.delegate = clash1
+    assertEquals(clash1, clash1.delegate)
+    clash1.setDelegate(clash2)
+    assertEquals(clash2, clash1.delegate())
+
+    clash2.delegate = clash1
+    assertEquals(clash1, clash2.delegate)
+    clash2.setDelegate(clash2)
+    assertEquals(clash2, clash2.delegate())
+}
+
 fun nsArrayOf(vararg elements: Any): NSArray = NSMutableArray().apply {
     elements.forEach {
         this.addObject(it as ObjCObject)