Xamarin iOS ném System.TypeInitializationException khi tải một thư viện gốc lớn

Question

Tôi có một ứng dụng iOS được xây dựng với Xamarin iOS bị treo khi tải lớp có thuộc tính DllImport cho các cuộc gọi PInvoke. Trường hợp ngoại lệ là:

Unhandled managed exception: An exception was thrown by the type initializer for Pazanga.Native.ZzPINVOKE (System.TypeInitializationException) 

Ứng dụng hoạt động tốt, nhưng bắt đầu gặp lỗi khi thư viện gốc tăng kích thước. Sau khi cắt xén một số phần của thư viện, nó đã hoạt động trở lại, nhưng sau khi liên kết một thư viện mới, nó lại bắt đầu gặp sự cố. Sự cố xảy ra trước khi bất kỳ cuộc gọi nào thực sự được thực hiện đối với thư viện gốc.

Đây là nhật ký thiết bị sau khi vụ tai nạn: http://pastebin.com/vW3CMXHq

Các trường hợp ngoại lệ bên trong là:

Aug 23 10:33:40 Outboxs-iPod pazanga[4216] <Warning>: System.TypeInitializationException: An exception was thrown by the type initializer for Pazanga.Native.ZzPINVOKE ---> System.TypeInitializationException: An exception was thrown by the type initializer for SWIGStringHelper ---> System.ExecutionEngineException: Attempting to JIT compile method '(wrapper native-to-managed) Pazanga.Native.ZzPINVOKE/SWIGStringHelper:CreateString (intptr)' while running with --aot-only. See http://docs.xamarin.com/ios/about/limitations for more information. 
at (wrapper managed-to-native) object:__icall_wrapper_mono_delegate_to_ftnptr (object) 
at (wrapper managed-to-native) Pazanga.Native.ZzPINVOKE/SWIGStringHelper:SWIGRegisterStringCallback_Zz (Pazanga.Native.ZzPINVOKE/SWIGStringHelper/SWIGStringDelegate) 
at Pazanga.Native.ZzPINVOKE+SWIGStringHelper..cctor() [0x00017] in /Users/max/Code/pazanga/mobile/ios/bindings/ZzPINVOKE.cs:229 
--- End of inner exception stack trace --- 
at Pazanga.Native.ZzPINVOKE..cctor() [0x0000a] in /Users/max/Code/pazanga/mobile/ios/bindings/ZzPINVOKE.cs:233 
--- End of inner exception stack trace --- 
at Pazanga.Native.Zz.locate (System.Byte[] image, image_format format, Int32 width, Int32 height, Int32 x, Int32 y) [0x00009] in /Users/max/Code/pazanga/mobile/ios/bindings/Zz.cs:16 
at Pazanga.CaptureDecode.ProcessFrame (System.Byte[] data, Int32 dataWidth, Int32 dataHeight, Boolean isPicture) [0x000cf] in /Users/max/Code/pazanga/mobile/common/CaptureDecode.cs:95 
at Pazanga.iOS.CaptureViewController.HandleNewFrame (System.Byte[] data, Int32 width, Int32 height) [0x0003b] in /Users/max/Code/pazanga/mobile/ios/App/CaptureViewController.cs:128 
at Pazanga.iOS.CaptureManager.OnNewFrame (System.Byte[] array, Int32 width, Int32 height) [0x00015] in /Users/max/Code/pazanga/mobile/ios/App/CaptureManager.cs:126 
at Pazanga.iOS.CaptureManager+OutputDelegate.DidOutputSampleBuffer (MonoTouch.AVFoundation.AVCaptureOutput captureOutput, MonoTouch.CoreMedia.CMSampleBuffer sampleBuffer, MonoTouch.AVFoundation.AVCaptureConnection connection) [0x000c6] in /Users/max/Code/pazanga/mobile/ios/App/CaptureManager.cs:110 
Aug 23 10:33:40 Outboxs-iPod pazanga[4216] <Warning>: System.TypeInitializationException: An exception was thrown by the type initializer for SWIGStringHelper ---> System.ExecutionEngineException: Attempting to JIT compile method '(wrapper native-to-managed) Pazanga.Native.ZzPINVOKE/SWIGStringHelper:CreateString (intptr)' while running with --aot-only. See http://docs.xamarin.com/ios/about/limitations for more information. 
at (wrapper managed-to-native) object:__icall_wrapper_mono_delegate_to_ftnptr (object) 
at (wrapper managed-to-native) Pazanga.Native.ZzPINVOKE/SWIGStringHelper:SWIGRegisterStringCallback_Zz (Pazanga.Native.ZzPINVOKE/SWIGStringHelper/SWIGStringDelegate) 
at Pazanga.Native.ZzPINVOKE+SWIGStringHelper..cctor() [0x00017] in /Users/max/Code/pazanga/mobile/ios/bindings/ZzPINVOKE.cs:229 
--- End of inner exception stack trace --- 
at Pazanga.Native.ZzPINVOKE..cctor() [0x0000a] in /Users/max/Code/pazanga/mobile/ios/bindings/ZzPINVOKE.cs:233 
Aug 23 10:33:40 Outboxs-iPod pazanga[4216] <Warning>: System.ExecutionEngineException: Attempting to JIT compile method '(wrapper native-to-managed) Pazanga.Native.ZzPINVOKE/SWIGStringHelper:CreateString (intptr)' while running with --aot-only. See http://docs.xamarin.com/ios/about/limitations for more information. 
at (wrapper managed-to-native) object:__icall_wrapper_mono_delegate_to_ftnptr (object) 
at (wrapper managed-to-native) Pazanga.Native.ZzPINVOKE/SWIGStringHelper:SWIGRegisterStringCallback_Zz (Pazanga.Native.ZzPINVOKE/SWIGStringHelper/SWIGStringDelegate) 
at Pazanga.Native.ZzPINVOKE+SWIGStringHelper..cctor() [0x00017] in /Users/max/Code/pazanga/mobile/ios/bindings/ZzPINVOKE.cs:229 

Và đây là lớp SWIGStringHelper (tạo ra bởi SWIG) xuất hiện trong ngoại lệ:

protected class SWIGStringHelper { 

    public delegate string SWIGStringDelegate(string message); 
    static SWIGStringDelegate stringDelegate = new SWIGStringDelegate(CreateString); 

    [DllImport("__Internal", EntryPoint="SWIGRegisterStringCallback_Zz")] 
    public static extern void SWIGRegisterStringCallback_Zz(SWIGStringDelegate stringDelegate); 

    [MonoTouch.MonoPInvokeCallback(typeof(SWIGStringDelegate))] 
    static string CreateString(string cString) { 
    return cString; 
    } 

    static SWIGStringHelper() { 
    SWIGRegisterStringCallback_Zz(stringDelegate); 
    } 
} 

Bất kỳ ý tưởng nào về cách giải quyết vấn đề này?

Answer 1

Để đóng vòng lặp ... Nó hóa ra là một bản sao của bug 14194 (gọi ngược lại bằng cách sử dụng một chuỗi).

A TypeInitializationException bị ném vì ngoại lệ xảy ra bên trong một hàm tạo tĩnh.