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Crash random when I close a modal window of sheet window

RogisterAlainRogisterAlain BEBeta ✭✭✭


Now in one day, I try to understand why my Xamarin.MAC application crash randomly when I close a modal window or a window sheet.

To try to see the problem, I open the window and I both X closed. I did not notice when I do this crash.

When only I open this window, I run a function that we can last 10 seconds and uses a webservice. I open the window and I close. After a while, I crash. Sometimes it happens when I close the window, sometimes by simply clicking a button in this window sometimes directly when executing the function.

I desperately looking for what can happen but I confess I do not understand. I have 2 possible errors that I put below.

I saw on this forum that someone had had a similar problem when closing modal / sheet window and told him to put in the project options: -registrar: static,

is what that can solve this problem?

I use the latest version BETA 2.8 Xamarin.MAC

Thank you


NSWindowGraphicsContext object 0x7ffb5ca0b450 overreleased while already deallocating; break on objc_overrelease_during_dealloc_error

Crashed Thread: 25 Dispatch queue: NSOperationQueue 0x7fd7fa5bf610 :: NSOperation 0x7fd7f77eb000 (QOS: USER_INTERACTIVE)

Exception Codes: KERN_INVALID_ADDRESS at 0x0000000000000018

VM Regions Near 0x18:
__TEXT 00000001015e6000-00000001019c6000 [ 3968K] r-x/rwx SM=COW /Users/USER/Library/Mobile Documents/com~apple~CloudDocs/*/

Application Specific Information:
abort() called

Thread 25 Crashed:: Dispatch queue: NSOperationQueue 0x7fd7fa5bf610 :: NSOperation 0x7fd7f77eb000 (QOS: USER_INTERACTIVE)
0 libsystem_kernel.dylib 0x00007fff8eb66f06 __pthread_kill + 10
1 libsystem_pthread.dylib 0x00007fff9279c4ec pthread_kill + 90
2 libsystem_c.dylib 0x00007fff8fa716e7 abort + 129
3 0x0000000101784452 mono_handle_native_sigsegv + 578 (mini-exceptions.c:2341)
4 0x00000001017902e1 mono_sigsegv_signal_handler + 225 (mini-runtime.c:2850)
5 libsystem_platform.dylib 0x00007fff9afcb52a _sigtramp + 26
6 ??? 000000000000000000 0 + 0
7 0x00007fff8b765fe7 -[NSCGSContext isFlipped] + 41
8 0x00007fff86446c90 __NSStringDrawingEngine + 7451
9 0x00007fff86443302 _NSStringDrawingCore + 159
10 0x00007fff8b71fab2 _NSDrawTextCell2 + 7035
11 0x00007fff8b728a53 -[NSTextFieldCell drawInteriorWithFrame:inView:] + 997
12 0x00007fff8b717ceb __40-[NSTextFieldCell drawWithFrame:inView:]_block_invoke + 451
13 0x00007fff8b6a0108 +[NSAppearance _performWithCurrentAppearance:usingBlock:] + 79
14 0x00007fff8b717a3f -[NSTextFieldCell drawWithFrame:inView:] + 238
15 0x00007fff8b711388 -[NSControl drawRect:] + 342
16 0x00007fff8b708cd2 -[NSView _drawRect:clip:] + 3626
17 0x00007fff8be32b35 -[_NSViewDrawOperation main] + 241
18 0x00007fff94641c7a -[__NSOperationInternal _start:] + 654
19 0x00007fff9463dc64 __NSOQSchedule_f + 194
20 libdispatch.dylib 0x00007fff8c24840b _dispatch_client_callout + 8
21 libdispatch.dylib 0x00007fff8c24d03b _dispatch_queue_drain + 754
22 libdispatch.dylib 0x00007fff8c253707 _dispatch_queue_invoke + 549
23 libdispatch.dylib 0x00007fff8c24bd53 _dispatch_root_queue_drain + 538
24 libdispatch.dylib 0x00007fff8c24bb00 _dispatch_worker_thread3 + 91
25 libsystem_pthread.dylib 0x00007fff927994de _pthread_wqthread + 1129
26 libsystem_pthread.dylib 0x00007fff92797341 start_wqthread + 13


  • RogisterAlainRogisterAlain BEBeta ✭✭✭

    I installed version 2.9 of Xamarin.MAC and my problem seems to have disappeared. I tried several times with the 2.8 and I always manage to reproduce the problem. With 2.9, I am no longer happened.

    Can anyone confirm that this problem has been solved?

    This message is completely random after many hours to understand what was happening:

    NSWindowGraphicsContext object 0x7ffb5ca0b450 overreleased while already deallocating; break it objc_overrelease_during_dealloc_error


  • ChrisHamonsChrisHamons USForum Administrator, Xamarin Team Xamurai

    Well, what your asking is hard (tm) without more than just a stack trace and a description. Hundreds of changes may have gone in between 2.8 in beta and 2.9, and even if I looked at and was familiar with each, which I am not, I'm unsure I could determine if we explicitly fixed this without significant research.

    If you could provide an example showing the issue, I could test it out on my end and possibly figure out what's going on. I could also provide you a "newer" 2.9 than what's in the Alpha channel, and you could see if it is "still fixed".

  • RogisterAlainRogisterAlain BEBeta ✭✭✭

    I have 2 problems. I still have the problem with 2.9

    I am trying to replicate the slows down the rendering in a small application but it is not easy of course. When you do X times something, and you do not know why it crashes when you close a window, I really do not understand.

    2 mistakes I see regularly:

    Crashed Thread: 16 Dispatch tail: NSOperationQueue 0x7f9c4603d240 :: NSOperation 0x7f9c46e2c9e0 (QOS: USER_INTERACTIVE)
    Exception Type: EXC_CRASH (SIGABRT)
    Exception Codes: 0x0000000000000000, 0x0000000000000000
    Exception Note: EXC_CORPSE_NOTIFY
    Application Specific Information:
    *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '*** - [{NSMapTable NSMapTable
    ] Count underflow '
    terminating with uncaught exception of types NSException
    abort () called Expired

    Thread 16 crashed with X86 Thread State (64-bit):
      rax: 0x0000000000000000 rbx: 0x0000000000000006 rcx: 0x0000700000093738 rdx: 0x0000000000000000
      rdi: 0x0000000000004b4b RSI: 0x0000000000000006 rbp: 0x0000700000093760 rsp: 0x0000700000093738
       r8: 0x0000000000000000 R9: 0x0000000000989680 r10: r11 0x000000000c000000: 0x0000000000000206
      r12: r13 0x00007000000938f0: 0x0000000000000000 r14: r15 0x0000700000094000: 0x00007000000937d0
      rip: 0x00007fff98505f06 rfl: 0x0000000000000206 a2: 0x00007f9c3b81900c


    Awake Time Since Boot: 600000 seconds
    System Integrity Protection: enabled
    Crashed Thread: 18 Dispatch tail: NSOperationQueue 0x7fc773073350 :: NSOperation 0x7fc7731a3470 (QOS: USER_INTERACTIVE)
    Exception Type: EXC_BAD_ACCESS (SIGABRT)
    Exception Codes: KERN_INVALID_ADDRESS at 0x0000000000000000
    Exception Note: EXC_CORPSE_NOTIFY
    VM Regions Near 0:
        __TEXT 000000010c914000-000000010ccf3000 [3964K] r-x / MS = rwx COW /Applications/
    Application Specific Information:
    objc [7911] NSWindowGraphicsContext object 0x7fc7728545f0 overreleased while already deallocating; break it to debug objc_overrelease_during_dealloc_error
    abort () called Expired

  • RogisterAlainRogisterAlain BEBeta ✭✭✭

    I was able to reproduce the problem in a small application. I sent to the support. I'll wait for their answer.

  • RogisterAlainRogisterAlain BEBeta ✭✭✭

    Hello, the carrier has a bug in Bugzilla for 3 days and still people have watched it.

    Please can you look at this bug because it's been two weeks I'm looking at this problem and this is incomprehensible. I really think the problem comes from a multiple call functions of a webservice.

    Thank you


  • ChrisHamonsChrisHamons USForum Administrator, Xamarin Team Xamurai

    Just to set expectations correctly. The XM dev team tries to be responsive in looking at bug reports quickly, especially those that block customers. However, based on existing work, previously filed bug, and a number of other variables, it may be a long time until your issue is reviewed.

    Bugzilla is not a support channel. Filing a bug and then posting on the forums \ bug for updates will not expedite any resolution.

    For those with business+ licenses, you are welcome to contact support at

    In this specific case, it appears the example is corrupting internal Cocoa state due to multiple sheets being shown, with multiple unnecssary invocations back to the main thread.

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