Native crash with AvnView accessibilityHitTest

[mohdimas]

Hi all,

Few of our users on Mac OS Seqoia (Darwin 24.5.0) have been getting random crash issue with the [AvnView accessibilityHitTest] and [AvnWindow automationPeer]. We're currently using Avalonia 11.2.2. The issue seems to happen when interacting with popups. We're guessing it might be related to a window manager app like Magnet, Moom or Rectangle.

Here's the full stack trace:

Crashed Thread:        0  CrBrowserMain  Dispatch queue: com.apple.main-thread

Exception Type:        EXC_BAD_ACCESS (SIGSEGV)
Exception Codes:       KERN_INVALID_ADDRESS at 0x0000000000000088
Exception Codes:       0x0000000000000001, 0x0000000000000088

Termination Reason:    Namespace SIGNAL, Code 11 Segmentation fault: 11
Terminating Process:   exc handler [3961]

VM Region Info: 0x88 is not in any region.  Bytes before following region: 4339072888
      REGION TYPE                    START - END         [ VSIZE] PRT/MAX SHRMOD  REGION DETAIL
      UNUSED SPACE AT START
--->  
      __TEXT                      102a10000-102b4c000    [ 1264K] r-x/r-x SM=COW  /Applications/Mailbird.app/Contents/MacOS/Mailbird

Thread 0 Crashed:: CrBrowserMain Dispatch queue: com.apple.main-thread
0   libAvaloniaNative.dylib       	       0x103807bec -[AvnView accessibilityChild] + 44
1   libAvaloniaNative.dylib       	       0x103807cc8 -[AvnView accessibilityHitTest:] + 36
2   AppKit                        	       0x197d7124c -[NSWindow(NSWindowAccessibility) accessibilityHitTest:] + 324
3   AppKit                        	       0x1976f06d0 -[NSApplication(NSApplicationAccessibility) accessibilityHitTest:] + 256
4   AppKit                        	       0x1976b36f0 CopyElementAtPosition + 164
5   HIServices                    	       0x199e7ba5c _AXXMIGCopyElementAtPosition + 384
6   HIServices                    	       0x199ea0ef8 _XCopyElementAtPosition + 328
7   HIServices                    	       0x199e59340 mshMIGPerform + 208
8   CoreFoundation                	       0x193a41a6c __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 60
9   CoreFoundation                	       0x193a4198c __CFRunLoopDoSource1 + 524
10  CoreFoundation                	       0x193a40350 __CFRunLoopRun + 2244
11  CoreFoundation                	       0x193a3f434 CFRunLoopRunSpecific + 608
12  HIToolbox                     	       0x19e1ef19c RunCurrentEventLoopInMode + 292
13  HIToolbox                     	       0x19e1eee2c ReceiveNextEventCommon + 220
14  HIToolbox                     	       0x19e1eed30 _BlockUntilNextEventMatchingListInModeWithFilter + 76
15  AppKit                        	       0x19729f8ac _DPSNextEvent + 660
16  AppKit                        	       0x197a95d98 -[NSApplication(NSEventRouting) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 700
17  AppKit                        	       0x197292be0 -[NSApplication run] + 476
18  libAvaloniaNative.dylib       	       0x1037f19fc PlatformThreadingInterface::RunLoop(IAvnLoopCancellation*) + 484

We still can't reproduce the issue, but maybe you know this better so any help would be appreciated.
Many thanks 🙏