Enable unused-function warning for runtime (#4628)

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

@@ -107,11 +107,13 @@ _Unwind_Reason_Code unwindCallback(
 
 THREAD_LOCAL_VARIABLE bool disallowSourceInfo = false;
 
+#if !OMIT_BACKTRACE && !USE_GCC_UNWIND
 SourceInfo getSourceInfo(KConstRef stackTrace, int index) {
   return disallowSourceInfo
       ? SourceInfo { .fileName = nullptr, .lineNumber = -1, .column = -1 }
       : Kotlin_getSourceInfo(*PrimitiveArrayAddressOfElementAt<KNativePtr>(stackTrace->array(), index));
 }
+#endif
 
 }  // namespace
 

kotlin-native/runtime/src/main/cpp/ObjCExport.mm

@@ -124,7 +124,6 @@ extern "C" OBJ_GETTER(Kotlin_ObjCExport_AllocInstanceWithAssociatedObject,
 }
 
 static Class getOrCreateClass(const TypeInfo* typeInfo);
-static void initializeClass(Class clazz);
 
 extern "C" id objc_retainAutoreleaseReturnValue(id self);
 
@@ -768,16 +767,6 @@ static KStdVector<const TypeInfo*> getProtocolsAsInterfaces(Class clazz) {
   return result;
 }
 
-static const TypeInfo* getMostSpecificKotlinClass(const TypeInfo* typeInfo) {
-  const TypeInfo* result = typeInfo;
-  while (getTypeAdapter(result) == nullptr) {
-    result = result->superType_;
-    RuntimeAssert(result != nullptr, "");
-  }
-
-  return result;
-}
-
 static int getVtableSize(const TypeInfo* typeInfo) {
   for (const TypeInfo* current = typeInfo; current != nullptr; current = current->superType_) {
     auto typeAdapter = getTypeAdapter(current);