我遇到了一次非常奇怪的崩溃，这是回溯。
* thread #1: tid = 0x2403, 0x3379516c CoreFoundation`CFHash + 8, stop reason = EXC_BREAKPOINT (code=EXC_ARM_BREAKPOINT, subcode=0xdefe)
frame #0: 0x3379516c CoreFoundation`CFHash + 8
frame #1: 0x33797a9c CoreFoundation`CFBasicHashRemoveValue + 1408
frame #2: 0x337974ee CoreFoundation`CFDictionaryRemoveValue + 166
frame #3: 0x3420988e Foundation`-[NSISEngine removeConstraintWithMarker:] + 562
frame #4: 0x34211dbe Foundation`-[NSLayoutConstraint _removeFromEngine:] + 230
frame #5: 0x35a954ec UIKit`-[UIView(UIConstraintBasedLayout) _layoutEngine_willRemoveLayoutConstraint:] + 44
frame #6: 0x358488fc UIKit`__48-[UIScrollView _setAutomaticContentConstraints:]_block_invoke_0 + 148
frame #7: 0x34208882 Foundation`-[NSISEngine withAutomaticOptimizationDisabled:] + 166
frame #8: 0x35848838 UIKit`-[UIScrollView _setAutomaticContentConstraints:] + 116
frame #9: 0x35848e6c UIKit`-[UIScrollView _rememberDependentConstraint:] + 112
frame #10: 0x35a9e3ae UIKit`___updateViewDependenciesForConstraint_block_invoke_0 + 30
frame #11: 0x35a954ba UIKit`_updateViewDependenciesForConstraint + 202
frame #12: 0x35a953da UIKit`-[UIView(UIConstraintBasedLayout) _layoutEngine_didAddLayoutConstraint:roundingAdjustment:mutuallyExclusiveConstraints:] + 154
frame #13: 0x35a95534 UIKit`-[UIView(UIConstraintBasedLayout) _tryToAddConstraintWithoutUpdatingConstraintsArray:roundingAdjustment:mutuallyExclusiveConstraints:] + 36
frame #14: 0x3567c2e0 UIKit`-[UIView(Internal) _didMoveFromWindow:toWindow:] + 376
frame #15: 0x356d34fe UIKit`-[UIScrollView _didMoveFromWindow:toWindow:] + 50
frame #16: 0x3567c5c6 UIKit`-[UIView(Internal) _didMoveFromWindow:toWindow:] + 1118
frame #17: 0x35676e52 UIKit`-[UIView(Hierarchy) _postMovedFromSuperview:] + 138
frame #18: 0x3565e7dc UIKit`-[UIView(Internal) _addSubview:positioned:relativeTo:] + 1300
frame #19: 0x3565e2c2 UIKit`-[UIView(Hierarchy) addSubview:] + 30
frame #20: 0x356f68e8 UIKit`-[UITransitionView transition:fromView:toView:removeFromView:] + 972
frame #21: 0x35937618 UIKit`__91-[UIWindowController transition:fromViewController:toViewController:target:didEndSelector:]_block_invoke_0238 + 388
frame #22: 0x357499b8 UIKit`-[UIWindowController transition:fromViewController:toViewController:target:didEndSelector:] + 4824
frame #23: 0x357b9814 UIKit`-[UIViewController _dismissViewControllerWithTransition:from:completion:] + 1708
frame #24: 0x357057c4 UIKit`-[UIViewController dismissViewControllerWithTransition:completion:] + 912
frame #25: 0x000ccd40 Capture`-[INFTagSearchViewController cancelButtonTouched:](self=0x1f09ed50, _cmd=0x001b9d5f, sender=0x1e0265c0) + 76 at INFTagSearchViewController.m:48
frame #26: 0x357470c4 UIKit`-[UIApplication sendAction:to:from:forEvent:] + 72
frame #27: 0x35747076 UIKit`-[UIApplication sendAction:toTarget:fromSender:forEvent:] + 30
frame #28: 0x35747054 UIKit`-[UIControl sendAction:to:forEvent:] + 44
frame #29: 0x3574690a UIKit`-[UIControl(Internal) _sendActionsForEvents:withEvent:] + 502
frame #30: 0x35746e00 UIKit`-[UIControl touchesEnded:withEvent:] + 488
frame #31: 0x3566f5f0 UIKit`-[UIWindow _sendTouchesForEvent:] + 524
frame #32: 0x3565c800 UIKit`-[UIApplication sendEvent:] + 380
frame #33: 0x3565c11a UIKit`_UIApplicationHandleEvent + 6154
frame #34: 0x373655a2 GraphicsServices`_PurpleEventCallback + 590
frame #35: 0x373651d2 GraphicsServices`PurpleEventCallback + 34
frame #36: 0x33829172 CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 34
frame #37: 0x33829116 CoreFoundation`__CFRunLoopDoSource1 + 138
frame #38: 0x33827f98 CoreFoundation`__CFRunLoopRun + 1384
frame #39: 0x3379aebc CoreFoundation`CFRunLoopRunSpecific + 356
frame #40: 0x3379ad48 CoreFoundation`CFRunLoopRunInMode + 104
frame #41: 0x373642ea GraphicsServices`GSEventRunModal + 74
frame #42: 0x356b0300 UIKit`UIApplicationMain + 1120
frame #43: 0x000a297c Capture`main(argc=1, argv=0x2fd60cfc) + 116 at main.m:16
frame #44: 0x3bb2bb20 libdyld.dylib`start + 4
您会注意到第 25 帧是我的代码进行的唯一调用，它是cancelButtonTouched看起来像。
- (IBAction)cancelButtonTouched:(id)sender {
[self dismissViewControllerAnimated:YES completion:nil];
}
我不知道发生了什么，我以前从未遇到过这样的问题，根据系统调用，它似乎是自动布局问题。我验证了在崩溃发生之前在呈现视图控制器上调用了 viewWillApper ，因此我认为这是在呈现视图布局期间出现的问题。
关于如何将这个问题缩小到特定布局约束的任何想法？或者还有其他想法吗？
这在某些设备上是可以重现的，而在其他设备上则很少发生。所以是间歇性的。
Update
断点的屏幕截图。
Update 2
因此，解雇绝对是一个问题presentingViewController，忽略两层深度（[self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:nil]）工作正常，但显然不是想要的结果，我只想返回 1 级。这进一步让我相信存在“重新布局”观点的问题。
我似乎记得类似的事情，虽然不确定是不是完全相同的事情。就我而言，这是由于使用已经是子视图的视图调用 addSubview: （或 insertSubview:...） 引起的。虽然通常我认为 UIView 可以处理这个问题，但通过自动布局，似乎某些关联信息可能会在其他地方添加两次，并且在尝试清除关联信息时可能会发生崩溃。就我而言，解决方案是确保我只添加一次子视图，并且此崩溃（或无论如何我的类似崩溃）消失了。