MonoTouch random crash on device, not on simulator

Question

I am thinking this is somehow memory related, but I have done everything I can think of. I have made sure classes are disposed property. Maintained hard references at the class level instead of function scope, for things that might be getting GC'd while I am using them, etc.

Basically the app works fine in the simulator, but crashes at the same spot on a real device. Seems like I get a few different stacks, but they are all around the same place.

I am using a large amount of events in my application. Too many threads?

Stacktrace:

at Newtonsoft.Json.JsonWriter.WriteValue (object) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue (Newtonsoft.Json.JsonWriter,object,Newtonsoft.Json.Serialization.JsonContract,Newtonsoft.Json.Serialization.JsonProperty,Newtonsoft.Json.Serialization.JsonContract) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.WriteMemberInfoProperty (Newtonsoft.Json.JsonWriter,object,Newtonsoft.Json.Serialization.JsonProperty,Newtonsoft.Json.Serialization.JsonContract) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject (Newtonsoft.Json.JsonWriter,object,Newtonsoft.Json.Serialization.JsonObjectContract,Newtonsoft.Json.Serialization.JsonProperty,Newtonsoft.Json.Serialization.JsonContract) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue (Newtonsoft.Json.JsonWriter,object,Newtonsoft.Json.Serialization.JsonContract,Newtonsoft.Json.Serialization.JsonProperty,Newtonsoft.Json.Serialization.JsonContract) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeList (Newtonsoft.Json.JsonWriter,Newtonsoft.Json.Utilities.IWrappedCollection,Newtonsoft.Json.Serialization.JsonArrayContract,Newtonsoft.Json.Serialization.JsonProperty,Newtonsoft.Json.Serialization.JsonContract) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue (Newtonsoft.Json.JsonWriter,object,Newtonsoft.Json.Serialization.JsonContract,Newtonsoft.Json.Serialization.JsonProperty,Newtonsoft.Json.Serialization.JsonContract) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.WriteMemberInfoProperty (Newtonsoft.Json.JsonWriter,object,Newtonsoft.Json.Serialization.JsonProperty,Newtonsoft.Json.Serialization.JsonContract) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject (Newtonsoft.Json.JsonWriter,object,Newtonsoft.Json.Serialization.JsonObjectContract,Newtonsoft.Json.Serialization.JsonProperty,Newtonsoft.Json.Serialization.JsonContract) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue (Newtonsoft.Json.JsonWriter,object,Newtonsoft.Json.Serialization.JsonContract,Newtonsoft.Json.Serialization.JsonProperty,Newtonsoft.Json.Serialization.JsonContract) at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.Serialize (Newtonsoft.Json.JsonWriter,object) at Newtonsoft.Json.JsonSerializer.SerializeInternal (Newtonsoft.Json.JsonWriter,object) at Newtonsoft.Json.JsonSerializer.Serialize (Newtonsoft.Json.JsonWriter,object) at RestSharp.Serializers.JsonSerializer.Serialize (object) [0x0001c] in /Users/sonmez56/Projects/TrackAbout.Mono/RestSharp/RestSharp/Serializers/JsonSerializer.cs:64 at RestSharp.RestRequest.AddBody (object,string) [0x00019] in /Users/sonmez56/Projects/TrackAbout.Mono/RestSharp/RestSharp/RestRequest.cs:203 at RestSharp.RestRequest.AddBody (object) [0x00000] in /Users/sonmez56/Projects/TrackAbout.Mono/RestSharp/RestSharp/RestRequest.cs:232 at TrackAboutMonoCore.Services.TrackAboutAPIRequestBuilder/TARestRequest.WithBody (T) <0x00097> at TrackAboutMonoCore.Services.ActionsService.CustomerSetVolume (int,System.Collections.Generic.List1<TrackAboutMonoCore.Models.Asset>,System.Action1>) [0x00000] in /Users/sonmez56/Projects/TrackAbout.Mono/TrackAboutMonoCore/Services/ActionsService.cs:24 at TrackAboutMonoCore.Controllers.LocateController.Save (object,System.EventArgs) [0x00055] in /Users/sonmez56/Projects/TrackAbout.Mono/TrackAboutMonoCore/Controllers/LocateController.cs:64 at MonoTouch.UIKit.UIBarButtonItem/Callback.Call (MonoTouch.Foundation.NSObject) [0x00010] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIBarButtonItem.cs:23 at (wrapper runtime-invoke) object.runtime_invoke_dynamic (intptr,intptr,intptr,intptr) <0xffffffff> at MonoTouch.UIKit.UIApplication.Main (string[],string,string) [0x0004c] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:38 at TrackAboutIOS.Application.Main (string[]) [0x00000] in /Users/sonmez56/Projects/TrackAbout.Mono/TrackAboutIOS/TrackAboutIOS/Main.cs:16 at (wrapper runtime-invoke) object.runtime_invoke_dynamic (intptr,intptr,intptr,intptr) <0xffffffff>

Native stacktrace:

0 TrackAboutIOS 0x01d20618 mono_handle_native_sigsegv + 280 1 TrackAboutIOS
0x01d45bd4 sigabrt_signal_handler + 180 2 libsystem_c.dylib
0x376647ed _sigtramp + 48 3 libsystem_c.dylib
0x3765a20f pthread_kill + 54 4 libsystem_c.dylib
0x3765329f abort + 94 5 TrackAboutIOS
0x01e394ac monoeg_g_log + 208 6 TrackAboutIOS
0x01d11664 get_numerous_trampoline + 160 7 TrackAboutIOS
0x01d11aac mono_aot_get_imt_thunk + 56 8 TrackAboutIOS
0x01dbdc50 initialize_imt_slot + 112 9 TrackAboutIOS
0x01dbf1c4 build_imt_slots + 1124 10 TrackAboutIOS
0x01dbf32c mono_vtable_build_imt_slot + 120 11 TrackAboutIOS
0x01d236fc mono_convert_imt_slot_to_vtable_slot + 292 12 TrackAboutIOS 0x01d23974 common_call_trampoline + 284 13 TrackAboutIOS 0x01d21c60 mono_vcall_trampoline + 228 14 TrackAboutIOS
0x00934198 generic_trampoline_vcall + 136 15 TrackAboutIOS
0x00b9fec4 Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_SerializeValue_Newtonsoft_Json_JsonWriter_object_Newtonsoft_Json_Serialization_JsonContract_Newtonsoft_Json_Serialization_JsonProperty_Newtonsoft_Json_Serialization_JsonContract + 1116 16 TrackAboutIOS 0x00ba13bc Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_WriteMemberInfoProperty_Newtonsoft_Json_JsonWriter_object_Newtonsoft_Json_Serialization_JsonProperty_Newtonsoft_Json_Serialization_JsonContract + 1712 17 TrackAboutIOS 0x00ba2a70 Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_SerializeObject_Newtonsoft_Json_JsonWriter_object_Newtonsoft_Json_Serialization_JsonObjectContract_Newtonsoft_Json_Serialization_JsonProperty_Newtonsoft_Json_Serialization_JsonContract + 1784 18 TrackAboutIOS 0x00ba0124 Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_SerializeValue_Newtonsoft_Json_JsonWriter_object_Newtonsoft_Json_Serialization_JsonContract_Newtonsoft_Json_Serialization_JsonProperty_Newtonsoft_Json_Serialization_JsonContract + 1724 19 TrackAboutIOS 0x00ba3ec0 Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_SerializeList_Newtonsoft_Json_JsonWriter_Newtonsoft_Json_Utilities_IWrappedCollection_Newtonsoft_Json_Serialization_JsonArrayContract_Newtonsoft_Json_Serialization_JsonProperty_Newtonsoft_Json_Serialization_JsonContract + 2520 20 TrackAboutIOS 0x00ba041c Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_SerializeValue_Newtonsoft_Json_JsonWriter_object_Newtonsoft_Json_Serialization_JsonContract_Newtonsoft_Json_Serialization_JsonProperty_Newtonsoft_Json_Serialization_JsonContract + 2484 21 TrackAboutIOS 0x00ba13bc Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_WriteMemberInfoProperty_Newtonsoft_Json_JsonWriter_object_Newtonsoft_Json_Serialization_JsonProperty_Newtonsoft_Json_Serialization_JsonContract + 1712 22 TrackAboutIOS 0x00ba2a70 Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_SerializeObject_Newtonsoft_Json_JsonWriter_object_Newtonsoft_Json_Serialization_JsonObjectContract_Newtonsoft_Json_Serialization_JsonProperty_Newtonsoft_Json_Serialization_JsonContract + 1784 23 TrackAboutIOS 0x00ba0124 Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_SerializeValue_Newtonsoft_Json_JsonWriter_object_Newtonsoft_Json_Serialization_JsonContract_Newtonsoft_Json_Serialization_JsonProperty_Newtonsoft_Json_Serialization_JsonContract + 1724 24 TrackAboutIOS 0x00b9f70c Newtonsoft_Json_Serialization_JsonSerializerInternalWriter_Serialize_Newtonsoft_Json_JsonWriter_object + 356 25 TrackAboutIOS 0x00b2c52c Newtonsoft_Json_JsonSerializer_SerializeInternal_Newtonsoft_Json_JsonWriter_object + 300 26 TrackAboutIOS 0x00b2c3b4 Newtonsoft_Json_JsonSerializer_Serialize_Newtonsoft_Json_JsonWriter_object + 156 27 TrackAboutIOS 0x012010c0 RestSharp_Serializers_JsonSerializer_Serialize_object + 452 28 TrackAboutIOS 0x011f8ad0 RestSharp_RestRequest_AddBody_object_string + 396 29 TrackAboutIOS
0x011f8e4c RestSharp_RestRequest_AddBody_object + 152 30 TrackAboutIOS 0x011d3c64 TrackAboutMonoCore_Services_TrackAboutAPIRequestBuilder_TARestRequest_WithBody_T_T + 152 31 TrackAboutIOS 0x011d22d4 TrackAboutMonoCore_Services_ActionsService_CustomerSetVolume_int_System_Collections_Generic_List_1_TrackAboutMonoCore_Models_Asset_System_Action_1_RestSharp_RestResponse_1_TrackAbout_Rest_Models_TARestResponse + 328 32 TrackAboutIOS 0x011ce3bc TrackAboutMonoCore_Controllers_LocateController_Save_object_System_EventArgs + 960 33 TrackAboutIOS 0x0139003c MonoTouch_UIKit_UIBarButtonItem_Callback_Call_MonoTouch_Foundation_NSObject + 96 34 TrackAboutIOS 0x008b0450 wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr + 200 35 TrackAboutIOS 0x01d05834 mono_jit_runtime_invoke + 1644 36 TrackAboutIOS
0x01dbd09c mono_runtime_invoke + 128 37 TrackAboutIOS
0x01e4c054 monotouch_trampoline + 3436 38 CoreFoundation
0x30c7f3fd -[NSObject performSelector:withObject:withObject:] + 52 39 UIKit 0x3353efaf -[UIApplication sendAction:to:from:forEvent:] + 62 40 UIKit
0x3360476b -[UIBarButtonItem(UIInternal) _sendAction:withEvent:] + 118 41 CoreFoundation 0x30c7f3fd -[NSObject performSelector:withObject:withObject:] + 52 42 UIKit
0x3353efaf -[UIApplication sendAction:to:from:forEvent:] + 62 43 UIKit 0x3353ef6b -[UIApplication sendAction:toTarget:fromSender:forEvent:] + 30 44 UIKit
0x3353ef49 -[UIControl sendAction:to:forEvent:] + 44 45 UIKit
0x3353ecb9 -[UIControl(Internal) _sendActionsForEvents:withEvent:] + 492 46 UIKit 0x3353f5f1 -[UIControl touchesEnded:withEvent:] + 476 47 UIKit
0x3353dad3 -[UIWindow _sendTouchesForEvent:] + 318 48 UIKit
0x3353d4c1 -[UIWindow sendEvent:] + 380 49 UIKit
0x3352383d -[UIApplication sendEvent:] + 356 50 UIKit
0x335230e3 _UIApplicationHandleEvent + 5826 51 GraphicsServices
0x33e1322b PurpleEventCallback + 882 52 CoreFoundation
0x30cf9523 CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION + 38 53 CoreFoundation 0x30cf94c5 CFRunLoopDoSource1 + 140 54 CoreFoundation 0x30cf8313 __CFRunLoopRun + 1370 55 CoreFoundation
0x30c7b4a5 CFRunLoopRunSpecific + 300 56 CoreFoundation
0x30c7b36d CFRunLoopRunInMode + 104 57 GraphicsServices
0x33e12439 GSEventRunModal + 136 58 UIKit
0x33551e7d UIApplicationMain + 1080 59 TrackAboutIOS
0x01696c74 wrapper_managed_to_native_MonoTouch_UIKit_UIApplication_UIApplicationMain_int_string_intptr_intptr + 240 60 TrackAboutIOS 0x00098420 TrackAboutIOS_Application_Main_string__ + 152 61 TrackAboutIOS
0x008b0450 wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr + 200 62 TrackAboutIOS 0x01d05834 mono_jit_runtime_invoke + 1644 63 TrackAboutIOS
0x01dbd09c mono_runtime_invoke + 128 64 TrackAboutIOS
0x01dc16b4 mono_runtime_exec_main + 436 65 TrackAboutIOS
0x01dc1a74 mono_runtime_run_main + 756 66 TrackAboutIOS
0x01d0c744 mono_jit_exec + 140 67 TrackAboutIOS
0x01e41110 main + 2288 68 TrackAboutIOS
0x0009826c start + 52

Answer 1

There's normally an exception type and message before the line:

Stacktrace:

It usually provides a good hint of the issue. Now the native stack trace also gives a clue here:

0x01e394ac monoeg_g_log + 208 6 TrackAboutIOS

0x01d11664 get_numerous_trampoline + 160 7 TrackAboutIOS

The first line tells us something was printed (or at least it tried to print) in your logs. It you check your device's log (e.g. using Xcode or mtouch --logdev) you should see the message.

The next line makes me think you're running out of trampolines (the error message will tell you which type). Here are the instructions on how to augment the number of trampolines available for your application.

Note: in case this is not trampoline-related please edit your question to add the exception type/message and the content of your device's log.