Object responds to selector but when I try send this selector - EXC_BAD_ACCESS

if ([timer respondsToSelector:@selector(userInfo)] ){
    [timer performSelector:@selector(userInfo)];
}

Timer is not nil and res开发者_开发问答ponds to selector. But I have EXC_BAD_ACCESS on 2 lines. How is this possible?

Try using NSZombieEnabled. Your timer is probably pointing to portion of memory that has been released...