did you ever find an answer to this question?

Okay in a sudden fit of clarity, I solved this problem.main.cppvoid do_corebluetooth stuff() { *ptr = get_bluetooth_object(); } int main() { std::thread worker(do_corebluetooth_stuff); }corebluetooth.mmvoid get_bluetooth_object() { // initialize the object void *ptr = [BlueToothObject alloc] init]; return ptr; } @implementation BlueToothObject // override constructor -(id)init { self = [super init]; if (self) { std::cout << "init ObjC" << std::endl; std::cout << "ObjC running on: " << std::this_thread::get_id() << std::endl; if ([NSThread isMainThread]) { std::cout << "we're on the main thread" << std::endl; } else { std::cout << "we're not on the main thread" << std::endl; } _centralQueue = dispatch_queue_create("centralmanager", DISPATCH_QUEUE_SERIAL); @autoreleasepool { dispatch_async(_centralQueue, ^{ std::cout << "inside here"; self.centralManager = [[CBCentralManager alloc] initWithDelegate:self queue:_centralQueue options:nil]; NSRunLoop *runLoop = [NSRunLoop currentRunLoop]; while (([runLoop runMode:NSDefaultRunLoopMode beforeDate:[NSDate distantFuture]])) { } [[NSRunLoop currentRunLoop] run]; }); }; return self; } }explanation: in c++ I dispatched a call to create a new CoreBlueToothObject object in a separate thread. Then I created a new serial dispatch queue that will be used to handle corebluetooth callbacks. Next I initialized the Central Manager using the new queue. Because CoreBluetooth needs a runloop to function and that's how callbacks are sent, I explicitly called a runloop on the current thread (which is not the main thread anymore).