CCTextureCache async thread semaphore init error: Function not implemented

I’m trying to use addImageAsync in my code. I’m running it on the Mac version and I get the error: CCTextureCache async thread semaphore init error: Function not implemented
then my images aren’t loaded and the callback that I set is never called. My code is pretty simple:

`void MainGame::loadWorldAsync(int worldNum) {
char imageFile[128];

sprintf(imageFile, "W%dBackgrounds.webp", worldNum);
CCTextureCache::sharedTextureCache()->addImageAsync(imageFile, this, callfuncO_selector(MainGame::loadWorldAsync2));

}`

What does that error mean?