Objective c 带有依赖项的NSOperationQueue错误_Objective C_Nsoperationqueue

Objective c 带有依赖项的NSOperationQueue错误

objective-c

Objective c 带有依赖项的NSOperationQueue错误,objective-c,nsoperationqueue,Objective C,Nsoperationqueue,我正在使用NSOperation和NSOperationQueue执行一系列操作，它们都是相互依赖的（2对1，3对2，等等）。我在创建操作后设置依赖项。当队列完成时，我遇到了一些问题：程序在代码的_release部分崩溃，显然是在操作被释放时。请注意，它们都在队列的末尾被释放，因为它只在最后一个队列之后，而最后一个队列依赖于第二个最后一个队列，这取决于等等。。。他们可以被释放。如果删除任何依赖项，代码运行良好。如果我将waituntillfinished：更改为NO，它将崩溃，如果更改为YES，

我正在使用NSOperation和NSOperationQueue执行一系列操作，它们都是相互依赖的（2对1，3对2，等等）。我在创建操作后设置依赖项。当队列完成时，我遇到了一些问题：程序在代码的_release部分崩溃，显然是在操作被释放时。请注意，它们都在队列的末尾被释放，因为它只在最后一个队列之后，而最后一个队列依赖于第二个最后一个队列，这取决于等等。。。他们可以被释放。如果删除任何依赖项，代码运行良好。如果我将waituntillfinished：更改为NO，它将崩溃，如果更改为YES，它不会崩溃

我已将问题隔离到以下代码，该代码不使用任何自定义类。默认情况下，NSOperation是一个完全不执行任何操作的类。然而，当所有操作都完成时，这仍然会崩溃。因此，我似乎没有正确使用NSOperationQueue，但看不出有什么问题。我正在运行10.9，我注意到一般来说，Maverick 10.9比10.8对这些问题更加敏感
我使用菜单项从主线程调用此方法：

- (void) testOperations:(id)object { NSOperationQueue* queue = [ [ NSOperationQueue alloc ] init ]; NSMutableArray* array = [ NSMutableArray array ]; for ( int i = 0; i < 10000; i++) [ array addObject: [[[ NSOperation alloc ] init ] autorelease ] ]; for ( int i = 1; i < [ array count ]; i++) [[ array objectAtIndex:i ] addDependency:[array objectAtIndex:i-1]]; // remove this and no crash [ queue addOperations: array waitUntilFinished:NO ]; // Change to YES, no crash [ queue autorelease ]; // or release, it does not make a difference, in fact leaking the memory makes no difference: the code crashes when the queue is removing the NSOperations }

-（void）testOperations:（id）对象 { NSOperationQueue*队列=[[NSOperationQueue alloc]init]； NSMutableArray*数组=[NSMutableArray]；对于（int i=0；i<10000；i++） [array addObject:[[[NSOperation alloc]init]自动释放]]；对于（int i=1；i<[数组计数]；i++） [[array objectAtIndex:i]addDependency:[array objectAtIndex:i-1]]；//删除此项不会导致崩溃 [queue addOperations:array waitUntilFinished:NO]；//更改为是，无崩溃 [queue autorelease]；//或者release，这没有什么区别，事实上，泄漏内存也没有什么区别：当队列删除操作时，代码崩溃 }
这将在以下情况下每次崩溃： bool objc:：DenseMapBase>，objc_object*，无符号长，objc:：DenseMapInfo，true>：（EXC_BAD_访问）
完整堆栈是：

#0 0x9104d81b in objc::DenseMapBase<objc::DenseMap<objc_object*, unsigned long, true, objc::DenseMapInfo<objc_object*> >, objc_object*, unsigned long, objc::DenseMapInfo<objc_object*>, true>::find(objc_object* const&) () #1 0x910384e3 in _objc_rootReleaseWasZero () #2 0x9104d5d9 in -[NSObject release] () #3 0x99e41224 in CFRelease () #4 0x99e56277 in -[__NSArrayM dealloc] () #5 0x9104d5ef in -[NSObject release] () #6 0x97f62b22 in -[__NSOperationInternal dealloc] () #7 0x9104d5ef in -[NSObject release] () #8 0x97f62ac8 in -[NSOperation dealloc] () #9 0x9104d5ef in -[NSObject release] () #10 0x99e41224 in CFRelease () #11 0x99e56277 in -[__NSArrayM dealloc] () #12 0x9104d5ef in -[NSObject release] () #13 0x97f62b22 in -[__NSOperationInternal dealloc] () #14 0x9104d5ef in -[NSObject release] () #15 0x97f62ac8 in -[NSOperation dealloc] () #16 0x9104d5ef in -[NSObject release] () #17 0x99e41224 in CFRelease () #18 0x99e56277 in -[__NSArrayM dealloc] () #19 0x9104d5ef in -[NSObject release] () #20 0x97f62b22 in -[__NSOperationInternal dealloc] () #21 0x9104d5ef in -[NSObject release] () #22 0x97f62ac8 in -[NSOperation dealloc] () #23 0x9104d5ef in -[NSObject release] () #24 0x99e41224 in CFRelease () #25 0x99e56277 in -[__NSArrayM dealloc] () #26 0x9104d5ef in -[NSObject release] () #27 0x97f62b22 in -[__NSOperationInternal dealloc] () #28 0x9104d5ef in -[NSObject release] () #29 0x97f62ac8 in -[NSOperation dealloc] () #30 0x9104d5ef in -[NSObject release] () #31 0x99e41224 in CFRelease () #32 0x99e56277 in -[__NSArrayM dealloc] () #33 0x9104d5ef in -[NSObject release] () #34 0x97f62b22 in -[__NSOperationInternal dealloc] () #35 0x9104d5ef in -[NSObject release] () #36 0x97f62ac8 in -[NSOperation dealloc] () #37 0x9104d5ef in -[NSObject release] () #38 0x99e41224 in CFRelease () #39 0x99e56277 in -[__NSArrayM dealloc] () #40 0x9104d5ef in -[NSObject release] () #41 0x97f62b22 in -[__NSOperationInternal dealloc] () #42 0x9104d5ef in -[NSObject release] () #43 0x97f62ac8 in -[NSOperation dealloc] () #44 0x9104d5ef in -[NSObject release] () #45 0x99e41224 in CFRelease () #46 0x99e56277 in -[__NSArrayM dealloc] () #47 0x9104d5ef in -[NSObject release] () #48 0x97f62b22 in -[__NSOperationInternal dealloc] () #49 0x9104d5ef in -[NSObject release] () #50 0x97f62ac8 in -[NSOperation dealloc] () #10722 0x9104d5ef in -[NSObject release] () #10723 0x97f62b22 in -[__NSOperationInternal dealloc] () #10724 0x9104d5ef in -[NSObject release] () #10725 0x97f62ac8 in -[NSOperation dealloc] () #10726 0x9104d5ef in -[NSObject release] () #10727 0x99e41224 in CFRelease () #10728 0x99e56277 in -[__NSArrayM dealloc] () #10729 0x9104d5ef in -[NSObject release] () #10730 0x97f62b22 in -[__NSOperationInternal dealloc] () #10731 0x9104d5ef in -[NSObject release] () #10732 0x97f62ac8 in -[NSOperation dealloc] () #10733 0x9104d5ef in -[NSObject release] () #10734 0x99e41224 in CFRelease () #10735 0x99e56277 in -[__NSArrayM dealloc] () #10736 0x9104d5ef in -[NSObject release] () #10737 0x97f62b22 in -[__NSOperationInternal dealloc] () #10738 0x9104d5ef in -[NSObject release] () #10739 0x97f62ac8 in -[NSOperation dealloc] () #10740 0x9104d5ef in -[NSObject release] () #10741 0x99e41224 in CFRelease () #10742 0x99e56277 in -[__NSArrayM dealloc] () #10743 0x9104d5ef in -[NSObject release] () #10744 0x97f62b22 in -[__NSOperationInternal dealloc] () #10745 0x9104d5ef in -[NSObject release] () #10746 0x97f62ac8 in -[NSOperation dealloc] () #10747 0x9104d5ef in -[NSObject release] () #10748 0x99e41224 in CFRelease () #10749 0x99e56277 in -[__NSArrayM dealloc] () #10750 0x9104d5ef in -[NSObject release] () #10751 0x97f62b22 in -[__NSOperationInternal dealloc] () #10752 0x9104d5ef in -[NSObject release] () #10753 0x97f62ac8 in -[NSOperation dealloc] () #10754 0x9104d5ef in -[NSObject release] () #10755 0x99e41224 in CFRelease () #10756 0x99e56277 in -[__NSArrayM dealloc] () #10757 0x9104d5ef in -[NSObject release] () #10758 0x97f62b22 in -[__NSOperationInternal dealloc] () #10759 0x9104d5ef in -[NSObject release] () #10760 0x97f62ac8 in -[NSOperation dealloc] () #10761 0x9104d5ef in -[NSObject release] () #10762 0x99e41224 in CFRelease () #10763 0x99e56277 in -[__NSArrayM dealloc] () #10764 0x9104d5ef in -[NSObject release] () #10765 0x97f62b22 in -[__NSOperationInternal dealloc] () #10766 0x9104d5ef in -[NSObject release] () #10767 0x97f62ac8 in -[NSOperation dealloc] () #10768 0x9104d5ef in -[NSObject release] () #10769 0x99e41224 in CFRelease () #10770 0x99e56277 in -[__NSArrayM dealloc] () #10771 0x9104d5ef in -[NSObject release] () #10772 0x97f62b22 in -[__NSOperationInternal dealloc] () #10773 0x9104d5ef in -[NSObject release] () #10774 0x97f62ac8 in -[NSOperation dealloc] () #10775 0x9104d5ef in -[NSObject release] () #10776 0x99e41224 in CFRelease () #10777 0x99e56277 in -[__NSArrayM dealloc] () #10778 0x9104d5ef in -[NSObject release] () #10779 0x97f62b22 in -[__NSOperationInternal dealloc] () #10780 0x9104d5ef in -[NSObject release] () #10781 0x97f62ac8 in -[NSOperation dealloc] () #10782 0x9104d5ef in -[NSObject release] () #10783 0x99e41224 in CFRelease () #10784 0x99e56277 in -[__NSArrayM dealloc] () #10785 0x9104d5ef in -[NSObject release] () #10786 0x97f62b22 in -[__NSOperationInternal dealloc] () #10787 0x9104d5ef in -[NSObject release] () #10788 0x97f62ac8 in -[NSOperation dealloc] () #10789 0x9104d5ef in -[NSObject release] () #10790 0x99e41224 in CFRelease () #10791 0x99e56277 in -[__NSArrayM dealloc] () #10792 0x9104d5ef in -[NSObject release] () #10793 0x97f62b22 in -[__NSOperationInternal dealloc] () #10794 0x9104d5ef in -[NSObject release] () #10795 0x97f62ac8 in -[NSOperation dealloc] () #10796 0x9104d5ef in -[NSObject release] () #10797 0x99e41224 in CFRelease () #10798 0x99e56277 in -[__NSArrayM dealloc] () #10799 0x9104d5ef in -[NSObject release] () #10800 0x97f62b22 in -[__NSOperationInternal dealloc] () #10801 0x9104d5ef in -[NSObject release] () #10802 0x97f62ac8 in -[NSOperation dealloc] () #10803 0x9104d5ef in -[NSObject release] () #10804 0x99e41224 in CFRelease () #10805 0x99e56277 in -[__NSArrayM dealloc] () #10806 0x9104d5ef in -[NSObject release] () #10807 0x97f62b22 in -[__NSOperationInternal dealloc] () #10808 0x9104d5ef in -[NSObject release] () #10809 0x97f62ac8 in -[NSOperation dealloc] () #10810 0x9104d5ef in -[NSObject release] () #10811 0x99e41224 in CFRelease () #10812 0x99e56277 in -[__NSArrayM dealloc] () #10813 0x9104d5ef in -[NSObject release] () #10814 0x97f62b22 in -[__NSOperationInternal dealloc] () #10815 0x9104d5ef in -[NSObject release] () #10816 0x97f62ac8 in -[NSOperation dealloc] () #10817 0x9104d5ef in -[NSObject release] () #10818 0x99e41224 in CFRelease () #10819 0x99e56277 in -[__NSArrayM dealloc] () #10820 0x9104d5ef in -[NSObject release] () #10821 0x97f62b22 in -[__NSOperationInternal dealloc] () #10822 0x9104d5ef in -[NSObject release] () #10823 0x97f62ac8 in -[NSOperation dealloc] () #10824 0x9104d5ef in -[NSObject release] () #10825 0x99e41224 in CFRelease () #10826 0x99e56277 in -[__NSArrayM dealloc] () #10827 0x9104d5ef in -[NSObject release] () #10828 0x97f62b22 in -[__NSOperationInternal dealloc] () #10829 0x9104d5ef in -[NSObject release] () #10830 0x97f62ac8 in -[NSOperation dealloc] () #10831 0x9104d5ef in -[NSObject release] () #10832 0x99e41224 in CFRelease () #10833 0x99e56277 in -[__NSArrayM dealloc] () #10834 0x9104d5ef in -[NSObject release] () #10835 0x97f62b22 in -[__NSOperationInternal dealloc] () #10836 0x9104d5ef in -[NSObject release] () #10837 0x97f62ac8 in -[NSOperation dealloc] () #10838 0x9104d5ef in -[NSObject release] () #10839 0x99e41224 in CFRelease () #10840 0x99e56277 in -[__NSArrayM dealloc] () #10841 0x9104d5ef in -[NSObject release] () #10842 0x97f62b22 in -[__NSOperationInternal dealloc] () #10843 0x9104d5ef in -[NSObject release] () #10844 0x97f62ac8 in -[NSOperation dealloc] () #10845 0x9104d5ef in -[NSObject release] () #10846 0x99e41224 in CFRelease () #10847 0x99e56277 in -[__NSArrayM dealloc] () #10848 0x9104d5ef in -[NSObject release] () #10849 0x97f62b22 in -[__NSOperationInternal dealloc] () #10850 0x9104d5ef in -[NSObject release] () #10851 0x97f62ac8 in -[NSOperation dealloc] () #10852 0x9104d5ef in -[NSObject release] () #10853 0x99e41224 in CFRelease () #10854 0x99e56277 in -[__NSArrayM dealloc] () #10855 0x9104d5ef in -[NSObject release] () #10856 0x97f62b22 in -[__NSOperationInternal dealloc] () #10857 0x9104d5ef in -[NSObject release] () #10858 0x97f62ac8 in -[NSOperation dealloc] () #10859 0x9104d5ef in -[NSObject release] () #10860 0x99e41224 in CFRelease () #10861 0x99e56277 in -[__NSArrayM dealloc] () #10862 0x9104d5ef in -[NSObject release] () #10863 0x97f62b22 in -[__NSOperationInternal dealloc] () #10864 0x9104d5ef in -[NSObject release] () #10865 0x97f62ac8 in -[NSOperation dealloc] () #10866 0x9104d5ef in -[NSObject release] () #10867 0x99e41224 in CFRelease () #10868 0x99e56277 in -[__NSArrayM dealloc] () #10869 0x9104d5ef in -[NSObject release] () #10870 0x97f62b22 in -[__NSOperationInternal dealloc] () #10871 0x9104d5ef in -[NSObject release] () #10872 0x97f62ac8 in -[NSOperation dealloc] () #10873 0x9104d5ef in -[NSObject release] () #10874 0x99e41224 in CFRelease () #10875 0x99e56277 in -[__NSArrayM dealloc] () #10876 0x9104d5ef in -[NSObject release] () #10877 0x97f62b22 in -[__NSOperationInternal dealloc] () #10878 0x9104d5ef in -[NSObject release] () #10879 0x97f62ac8 in -[NSOperation dealloc] () #10880 0x9104d5ef in -[NSObject release] () #10881 0x99e41224 in CFRelease () #10882 0x99e56277 in -[__NSArrayM dealloc] () #10883 0x9104d5ef in -[NSObject release] () #10884 0x97f62b22 in -[__NSOperationInternal dealloc] () #10885 0x9104d5ef in -[NSObject release] () #10886 0x97f62ac8 in -[NSOperation dealloc] () #10887 0x9104d5ef in -[NSObject release] () #10888 0x99e41224 in CFRelease () #10889 0x99e56277 in -[__NSArrayM dealloc] () #10890 0x9104d5ef in -[NSObject release] () #10891 0x97f62b22 in -[__NSOperationInternal dealloc] () #10892 0x9104d5ef in -[NSObject release] () #10893 0x97f62ac8 in -[NSOperation dealloc] () #10894 0x9104d5ef in -[NSObject release] () #10895 0x99e41224 in CFRelease () #10896 0x99e56277 in -[__NSArrayM dealloc] () #10897 0x9104d5ef in -[NSObject release] () #10898 0x97f62b22 in -[__NSOperationInternal dealloc] () #10899 0x9104d5ef in -[NSObject release] () #10900 0x97f62ac8 in -[NSOperation dealloc] () #10901 0x9104d5ef in -[NSObject release] () #10902 0x99e41224 in CFRelease () #10903 0x99e56277 in -[__NSArrayM dealloc] () #10904 0x9104d5ef in -[NSObject release] () #10905 0x97f62b22 in -[__NSOperationInternal dealloc] () #10906 0x9104d5ef in -[NSObject release] () #10907 0x97f62ac8 in -[NSOperation dealloc] () #10908 0x9104d5ef in -[NSObject release] () #10909 0x99e41224 in CFRelease () #10910 0x99e56277 in -[__NSArrayM dealloc] () #10911 0x9104d5ef in -[NSObject release] () #10912 0x97f62b22 in -[__NSOperationInternal dealloc] () #10913 0x9104d5ef in -[NSObject release] () #10914 0x97f62ac8 in -[NSOperation dealloc] () #10915 0x9104d5ef in -[NSObject release] () #10916 0x97f49cca in __NSOQSchedule_f () #10917 0x9c1c9e21 in _dispatch_async_redirect_invoke () #10918 0x9c1c53a6 in _dispatch_client_callout () #10919 0x9c1c7467 in _dispatch_root_queue_drain () #10920 0x9c1c8732 in _dispatch_worker_thread2 () #10921 0x960c2dab in _pthread_wqthread ()
objc:：DenseMapBase:：find（objc_object*const&）中的0 0x9104d81b #1 0x910384e3在_objc_rootReleaseWasZero（）中 #2 0x9104d5d9英寸-[NSObject release]（） #CFRelease（）中的3 0x99e41224 #4 0x99e56277英寸-[\uu NSArrayM dealloc]（） #5 0x9104d5ef输入-[NSObject释放]（） #6 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #7 0x9104d5ef输入-[NSObject释放]（） #8 0x97f62ac8 in-[NSOperation dealloc]（） #9 0x9104d5ef输入-[NSObject释放]（） #CFRelease（）中的10 0x99e41224 #11 0x99e56277英寸-[\uu NSArrayM dealloc]（） #12 0x9104d5ef输入-[NSObject释放]（） #13 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #14 0x9104d5ef输入-[NSObject释放]（） #15 0x97f62ac8 in-[NSOperation dealloc]（） #16 0x9104d5ef输入-[NSObject释放]（） #17 0x99e41224在CFR版本中（） #18 0x99e56277英寸-[[uuu NSArrayM dealloc]（） #19 0x9104d5ef输入-[NSObject释放]（） #20 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #21 0x9104d5ef输入-[NSObject释放]（） #22 0x97f62ac8 in-[NSOperation dealloc]（） #23 0x9104d5ef输入-[NSObject释放]（） #CFRelease（）中的24 0x99e41224 #25 0x99e56277英寸-[\uu NSArrayM dealloc]（） #26 0x9104d5ef输入-[NSObject释放]（） #27 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #28 0x9104d5ef输入-[NSObject释放]（） #29 0x97f62ac8 in-[NSOperation dealloc]（） #30 0x9104d5ef输入-[NSObject释放]（） #CFRelease中的31 0x99e41224（） #32 0x99e56277英寸-[\uu NSArrayM dealloc]（） #33 0x9104d5ef输入-[NSObject释放]（） #34 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #35 0x9104d5ef输入-[NSObject释放]（） #36 0x97f62ac8 in-[NSOperation dealloc]（） #37 0x9104d5ef输入-[NSObject释放]（） #38 0x99e41224英寸CFR释放（） #39 0x99e56277英寸-[\uu NSArrayM dealloc]（） #40 0x9104d5ef输入-[NSObject释放]（） #41 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #42 0x9104d5ef输入-[NSObject释放]（） #43 0x97f62ac8 in-[NSOperation dealloc]（） #44 0x9104d5ef输入-[NSObject释放]（） #45 0x99e41224英寸CFR释放（） #46 0x99e56277英寸-[\uu NSArrayM dealloc]（） #47 0x9104d5ef输入-[NSObject释放]（） #48 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #49 0x9104d5ef输入-[NSObject释放]（） #50 0x97f62ac8英寸-[NSOperation dealloc]（） #10722 0x9104d5ef输入-[NSObject释放]（） #10723 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #10724 0x9104d5ef输入-[NSObject释放]（） #10725 0x97f62ac8 in-[NSOperation dealloc]（） #10726 0x9104d5ef输入-[NSObject释放]（） #CFRelease（）中的10727 0x99e41224 #10728 0x99e56277英寸-[\uu NSArrayM dealloc]（） #10729 0x9104d5ef输入-[NSObject释放]（） #10730 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #10731 0x9104d5ef输入-[NSObject释放]（） #10732 0x97f62ac8 in-[NSOperation dealloc]（） #10733 0x9104d5ef输入-[NSObject释放]（） #CFRelease（）中的10734 0x99e41224 #10735 0x99e56277英寸-[\uu NSArrayM dealloc]（） #10736 0x9104d5ef输入-[NSObject释放]（） #10737 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #10738 0x9104d5ef输入-[NSObject释放]（） #10739 0x97f62ac8 in-[NSOperation dealloc]（） #10740 0x9104d5ef输入-[NSObject释放]（） #CFRelease（）中的10741 0x99e41224 #10742 0x99e56277英寸-[\uu NSArrayM dealloc]（） #10743 0x9104d5ef输入-[NSObject释放]（） #10744 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #10745 0x9104d5ef输入-[NSObject释放]（） #10746 0x97f62ac8 in-[NSOperation dealloc]（） #10747 0x9104d5ef输入-[NSObject释放]（） #CFRelease（）中的10748 0x99e41224 #10749 0x99e56277英寸-[\uu NSArrayM dealloc]（） #10750 0x9104d5ef输入-[NSObject释放]（） #10751 0x97f62b22英寸-[\uu n操作内部解除锁定]（） #10752 0x9104d5ef输入-[NSObject释放]（） #10753 0x97f62ac8 in-[NSOperation dealloc]（） #10754 0x9104d5ef输入-[NSObject释放]（） #CFRelease（）中的10755 0x99e41224 #10756 0x99e56277英寸-[\uu NSArrayM dealloc]（） #10757 0x9104d5ef输入-[NSObject释放]（） #10758
libobjc.A.dylib`objc::DenseMapBase<objc::DenseMap<objc_object*, unsigned long, true, objc::DenseMapInfo<objc_object*> >, objc_object*, unsigned long, objc::DenseMapInfo<objc_object*>, true>::find(objc_object* const&): 0x9104d800: pushl %ebp 0x9104d801: movl %esp, %ebp 0x9104d803: pushl %esi 0x9104d804: subl $20, %esp 0x9104d807: leal -8(%ebp), %eax 0x9104d80a: movl %eax, 8(%esp) 0x9104d80e: movl 16(%ebp), %eax 0x9104d811: movl %eax, 4(%esp) 0x9104d815: movl 12(%ebp), %esi 0x9104d818: movl %esi, (%esp) **0x9104d81b: calll 0x9104d9b6 ; bool objc::DenseMapBase<objc::DenseMap<objc_object*, unsigned long, true, objc::DenseMapInfo<objc_object*> >, objc_object*, unsigned long, objc::DenseMapInfo<objc_object*>, true>::LookupBucketFor<objc_object*>(objc_object* const&, std::__1::pair<objc_object*, unsigned long> const*&) const** 0x9104d820: movl 12(%esi), %ecx 0x9104d823: shll $3, %ecx 0x9104d826: addl (%esi), %ecx 0x9104d828: movl 8(%ebp), %edx 0x9104d82b: testb %al, %al 0x9104d82d: je 0x9104d836 ; objc::DenseMapBase<objc::DenseMap<objc_object*, unsigned long, true, objc::DenseMapInfo<objc_object*> >, objc_object*, unsigned long, objc::DenseMapInfo<objc_object*>, true>::find(objc_object* const&) + 54 0x9104d82f: movl -8(%ebp), %eax 0x9104d832: movl %eax, (%edx) 0x9104d834: jmp 0x9104d838 ; objc::DenseMapBase<objc::DenseMap<objc_object*, unsigned long, true, objc::DenseMapInfo<objc_object*> >, objc_object*, unsigned long, objc::DenseMapInfo<objc_object*>, true>::find(objc_object* const&) + 56 0x9104d836: movl %ecx, (%edx) 0x9104d838: movl %ecx, 4(%edx) 0x9104d83b: addl $20, %esp 0x9104d83e: popl %esi 0x9104d83f: popl %ebp 0x9104d840: ret $4 0x9104d843: nop

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification { NSOperationQueue* aQueue = [[ NSOperationQueue alloc ] init ]; NSMutableArray* array = [ NSMutableArray array ]; for ( int i = 0; i < 4269; i++) [ array addObject: [ [NSOperation alloc ] init ]]; for ( int i = 1; i < [ array count ]; i++) [[ array objectAtIndex:i ] addDependency:[array objectAtIndex:i-1]]; [ aQueue addOperations: array waitUntilFinished:NO ]; }

static NSOperationQueue* aQueue = nil; - (void)applicationDidFinishLaunching:(NSNotification *)aNotification { aQueue = [[ NSOperationQueue alloc ] init ]; NSOperation* lastOp = nil; for ( int i = 0; i < 5000 ; i++) { NSOperation* newOp = [ NSBlockOperation blockOperationWithBlock:^{ ;} ]; if ( lastOp != nil ) [ newOp addDependency: lastOp ]; [ aQueue addOperation:newOp ]; lastOp = newOp; } }

static NSMutableArray* array; - (void)applicationDidFinishLaunching:(NSNotification *)aNotification { NSOperationQueue* aQueue = [[ NSOperationQueue alloc ] init ]; aQueue.maxConcurrentOperationCount = 1; array = [ NSMutableArray arrayWithCapacity:10000]; @autoreleasepool { for ( int i = 0; i < 10000; i++) [ array addObject: [NSBlockOperation blockOperationWithBlock:(void (^)(void))^{ NSLog(@"executing %d", i); }]]; } for ( int i = 1; i < [ array count ]; i++) [[ array objectAtIndex:i ] addDependency:[array objectAtIndex:i-1]]; [ aQueue addOperations: array waitUntilFinished:NO ]; }

#import <Foundation/Foundation.h> @interface Holder : NSObject @property (strong) id object; @property (assign) int i; - (void) dealloc; @end @implementation Holder - (void) dealloc { [ _object release ]; [ super dealloc ]; } @end int main(int argc, const char * argv[]) { @autoreleasepool { Holder* lastObject = nil; for ( int i = 0; i < 1000000; i++) { Holder* anObject = [[[ Holder alloc ] init] autorelease ]; if ( lastObject != nil ) lastObject.object = anObject; lastObject = anObject; } } }

@implementation MyOperation - (void) main { ... NSArray* dependencies = self.dependencies; for (NSOperation* op in dependencies) [self removeDependency:op]; } @end

@implementation SafeOperation - (void)dealloc { __block NSArray<NSOperation *> *dependencies = nil; @autoreleasepool { dependencies = self.dependencies; if ([dependencies count] == 0) { return; } for (NSOperation *op in dependencies) { [self removeDependency:op]; } } dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{ dependencies = nil; }); } @end