no ahead of time (AOT) code was generated - ios

I use Resources.Load read some txt file in Resources subfolders, then I use TinyCsvParser pasrse the content, it works in the editor,when build to iOS, It posts below error, Is there any advice.
Thank you!
System.AggregateException: One or more errors occurred. ---> System.ExecutionEngineException: Attempting to call method 'System.Linq.Expressions.Interpreter.LightLambda::RunVoid2<Country,System.Boolean>' for which no ahead of time (AOT) code was generated.
at System.Action`2[T1,T2].Invoke (T1 arg1, T2 arg2) [0x00000] in <00000000000000000000000000000000>:0
at TinyCsvParser.Mapping.CsvPropertyMapping`2[TEntity,TProperty].TryMapValue (TEntity entity, System.String value) [0x00000] in <00000000000000000000000000000000>:0
at TinyCsvParser.Mapping.CsvMapping`1[TEntity].Map (TinyCsvParser.Model.TokenizedRow values) [0x00000] in <00000000000000000000000000000000>:0
at System.Func`2[T,TResult].Invoke (T arg) [0x00000] in <00000000000000000000000000000000>:0
at System.Linq.Parallel.SelectQueryOperator`2+SelectQueryOperatorEnumerator`1[TInput,TOutput,TKey].MoveNext (TOutput& currentElement, TKey& currentKey) [0x00000] in <00000000000000000000000000000000>:0
at System.Linq.Parallel.OrderPreservingPipeliningSpoolingTask`2[TOutput,TKey].SpoolingWork () [0x00000] in <00000000000000000000000000000000>:0
at System.Linq.Parallel.SpoolingTaskBase.Work () [0x00000] in <00000000000000000000000000000000>:0
at System.Linq.Parallel.QueryTask.BaseWork (System.Object unused) [0x00000] in <00000000000000000000000000000000>:0
at System.Action`1[T].Invoke (T obj) [0x00000] in <00000000000000000000000000000000>:0
at System.Threading.Tasks.Task.Execute () [0x00000] in <00000000000000000000000000000000>:0
at System.Threading.ContextCallback.Invoke (System.Object state) [0x00000] in <00000000000000000000000000000000>:0
at System.Threading.ExecutionContext.RunInternal (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) [0x00000] in <00000000000000000000000000000000>:0
at System.Threading.Tasks.Task.ExecuteWithThreadLocal (System.Threading.Tasks.Task& currentTaskSlot) [0x00000] in <00000000000000000000000000000000>:0
at System.Threading.Tasks.Task.ExecuteEntry (System.Boolean bPreventDoubleExecution) [0x00000] in <00000000000000000000000000000000>:0
at System.Threading.ThreadPoolWorkQueue.Dispatch () [0x00000] in <00000000000000000000000000000000>:0
unity version: 2019.4
Xcode version: 11.4

Related

Record fields in z3

model record by datatype in z3
if two record datatype have the same field, e.g.,
UNI_MSG : record
Cmd : UNI_CMD;
Proc : NODE;
HomeProc : boolean;
Data : DATA;
end;
INV_CMD : enum {INV_None, INV_Inv, INV_InvAck};
INV_MSG : record
Cmd : INV_CMD;
end;
RP_CMD : enum {RP_None, RP_Replace};
RP_MSG : record
Cmd : RP_CMD;
end;
both UNI_MSG and RP_MSG have the fields Cmd.
when I use the Cmd field of a UNI_MSG record variable, I don't know how to
use it because an RP_CMD variable also has the Cmd field.
z3 code is as follows:
; This example illustrates basic arithmetic and
; uninterpreted functions
(declare-datatypes () ((CACHE_STATE CACHE_I CACHE_S CACHE_E)))
(declare-datatypes () ((NODE_CMD NODE_None NODE_Get NODE_GetX)))
(declare-datatypes () ((UNI_CMD UNI_None UNI_Get UNI_GetX UNI_Put UNI_PutX UNI_Nak)))
(declare-datatypes () ((INV_CMD INV_None INV_Inv INV_InvAck)))
(declare-datatypes () ((RP_CMD RP_None RP_Replace)))
(declare-datatypes () ((WB_CMD WB_None WB_Wb)))
(declare-datatypes () ((SHWB_CMD SHWB_None SHWB_ShWb SHWB_FAck)))
(declare-datatypes () ((NAKC_CMD NAKC_None NAKC_Nakc)))
(define-sort NODE () Int)
(define-sort DATA () Int)
(define-sort boolean () Bool)
(declare-datatypes () ((Record_0 (mk-Record_0 (Cmd NAKC_CMD)))))
(declare-datatypes () ((Record_1 (mk-Record_1 (Data DATA)
(HomeProc boolean)
(Proc NODE)
(Cmd SHWB_CMD)))))
(declare-datatypes () ((Record_2 (mk-Record_2 (HomeInvSet boolean)
(InvSet (Array NODE boolean))
(HomeShrSet boolean)
(ShrSet (Array NODE boolean))
(ShrVld boolean)
(HomeHeadPtr boolean)
(HeadPtr NODE)
(HeadVld boolean)
(Dirty boolean)
(Local boolean)
(Pending boolean)))))
(declare-datatypes () ((Record_3 (mk-Record_3 (CacheData DATA)
(CacheState CACHE_STATE)
(InvMarked boolean)
(ProcCmd NODE_CMD)))))
(declare-datatypes () ((Record_4 (mk-Record_4 (CurrData DATA)
( NakcMsg ( Record_0))
( ShWbMsg ( Record_1))
( WbMsg ( Record_1))
( HomeRpMsg ( Record_0))
( RpMsg (Array NODE Record_0))
( HomeInvMsg ( Record_0))
( InvMsg (Array NODE Record_0))
( HomeUniMsg ( Record_1))
( UniMsg (Array NODE Record_1))
(MemData DATA)
( Dir ( Record_2))
( HomeProc ( Record_3))
( Proc (Array NODE Record_3))))))
(declare-const Sta ( Record_4))
(assert (= (Cmd (select (UniMsg Sta) 1 )) UNI_Nak))
(check-sat)
The error is caused by both record_0 and record_1 having field Cmd.
You can work around this by renaming them to Cmd0, Cmd1 etc.
SMTLib actually allows the same name to be used in fields with other types, but the type system is too weak and requires you to put ascriptions to work around it. If you really want to keep the name, post a (much!) smaller version of this problem so we can show you how to do that. But in practice, renaming is the best (and simplest!) way to go.

exception in xamarin.forms in System.Net.Http

I have this exception that i printed in my log that cause the app to crash in android, motorola device xt1058.
The problem is that I don't have the device and I got the log from the client who sent me the log file.
I have no idea where the logs comes from.
I have all the app wrapped in try catch but still the app crashed
09:37:10 - Error in TaskSchedulerOnUnobservedTaskException:
A Task's exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was rethrown by the finalizer thread.
09:37:11 - Error in TaskSchedulerOnUnobservedTaskException: System.AggregateException: A Task's exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was rethrown by the finalizer thread. ---> System.Net.WebException: Error: NameResolutionFailure
at System.Net.HttpWebRequest.EndGetResponse (System.IAsyncResult asyncResult) [0x00064] in <552eeeb8705c4abb9eeb5ebce43b6865>:0
at System.Threading.Tasks.TaskFactory1[TResult].FromAsyncCoreLogic (System.IAsyncResult iar, System.Func2[T,TResult] endFunction, System.Action1[T] endAction, System.Threading.Tasks.Task1[TResult] promise, System.Boolean requiresSynchronization) [0x00014] in <52ca43e23d764403a7855ae066156266>:0
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0004e] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.ConfiguredTaskAwaitable1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in <52ca43e23d764403a7855ae066156266>:0
at System.Net.Http.HttpClientHandler+<SendAsync>c__async0.MoveNext () [0x0041e] in <21d260c0947046f0aae7990757a51ba3>:0
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0004e] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.ConfiguredTaskAwaitable1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in <52ca43e23d764403a7855ae066156266>:0
at System.Net.Http.HttpClient+c__async0.MoveNext () [0x000f3] in <21d260c0947046f0aae7990757a51ba3>:0
--- End of inner exception stack trace ---
---> (Inner Exception #0) System.Net.WebException: Error: NameResolutionFailure
at System.Net.HttpWebRequest.EndGetResponse (System.IAsyncResult asyncResult) [0x00064] in <552eeeb8705c4abb9eeb5ebce43b6865>:0
at System.Threading.Tasks.TaskFactory1[TResult].FromAsyncCoreLogic (System.IAsyncResult iar, System.Func2[T,TResult] endFunction, System.Action1[T] endAction, System.Threading.Tasks.Task1[TResult] promise, System.Boolean requiresSynchronization) [0x00014] in <52ca43e23d764403a7855ae066156266>:0
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0004e] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.ConfiguredTaskAwaitable1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in <52ca43e23d764403a7855ae066156266>:0
at System.Net.Http.HttpClientHandler+<SendAsync>c__async0.MoveNext () [0x0041e] in <21d260c0947046f0aae7990757a51ba3>:0
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0004e] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in <52ca43e23d764403a7855ae066156266>:0
at System.Runtime.CompilerServices.ConfiguredTaskAwaitable1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in <52ca43e23d764403a7855ae066156266>:0
at System.Net.Http.HttpClient+c__async0.MoveNext () [0x000f3] in <21d260c0947046f0aae7990757a51ba3>:0 <---
the problem is with one of the http call which leads you to this error, so cross check your API on Postman extension if it returns what you expect. check your website is running, check network status and please have a habit of surrounding these calls with try and catch.
Once you surround all your http calls with try catch put your debugger in the catch statement understand the exception and verify the same URL.

How to empty a list

I was trying to figure out the way to empty a list (seen as a stack) in Common Lisp.
I came up with this:
(defun emptystack ()
(dolist (var *stack*) (pop *stack*)))
But it generates a warning at compile time (VAR is defined but never used).
Then I thought that it would have been simpler just to do:
(setq *stack* nil)
But still, I was wondering if there was any way to do it manually like in the first function, but without any unused variable.
One can declare to ignore the unused variable:
(defun emptystack ()
(dolist (var *stack*)
(declare (ignore var))
(pop *stack*)))
With the DO macro:
(defun emptystack ()
(do () ; no bindings
((null *stack*)) ; end test, no further results
(pop *stack*))) ; body
In LOOP one can also ignore the variable by naming it nil:
(defun emptystack ()
(loop for nil in *stack* do (pop *stack*)))
You could use
(defun emptystack ()
(loop while *stack* do (pop *stack*)))
which indeed does not use a variable under the hood:
? (macroexpand-1 '(loop while *stack* do (pop *stack*)))
(BLOCK NIL (ANSI-LOOP::LOOP-BODY NIL ((UNLESS *STACK* (GO ANSI-LOOP::END-LOOP))) ((POP *STACK*)) ((UNLESS *STACK* (GO ANSI-LOOP::END-LOOP))) NIL))

F# - Mono crashes/ returns inconsistent

I am trying to learn F# and I have some background in Standard ML. I am working through the text "Functional Approach to Programming" converting its code into F#. The code sample presented below is from the book mentioned above.
in SML
datatype 'a genTree = GenNode of 'a * ('a genTree list);;
val tree: string genTree =
GenNode("a", [GenNode("b", []),
GenNode("c", [GenNode("d", []),
GenNode("e", [])]),
GenNode("f", [])]);;
fun map f [] = []
| map f (l::ls) = (f l) :: (map f ls);;
fun foldl f e [] = e
| foldl f e (l::ls) = foldl f (f(e, l)) ls;;
fun sigma xs = foldl (op +) 0 xs;;
fun genSize (GenNode(_, ls)) =
1 + sigma (map genSize ls);;
SML> genSize tree (* returns 6: int *)
Attempt One - in F# Interactive Shell F# 3.1 (this one crashes the shell)
type genTree<'a> = GenNode of 'a * genTree<'a> list;;
let tree: string genTree =
GenNode("a", [GenNode("b", []);
GenNode("c", [GenNode("d", []);
GenNode("e", [])]);
GenNode("f", [])]);;
let rec map f ls =
match ls with
| [] -> []
| (l::ls) -> (f l) :: (map f ls);;
let rec foldl f e ls =
match ls with
| [] -> e
| (l::ls) -> foldl f (f e l) ls;;
let sigma ls = foldl ( + ) 0 ls;;
let rec genSize (GenNode(lbl, ls)) =
1 + sigma(map genSize ls);;
Attempt Two - in F# Interactive Shell F# 3.1 (give a base case for genSize, hoping that'll do the trick!)
Here is the new definition for genSize, the rest of the code from attempt #1 carries unchanged.
let rec genSize (t: genTree<'a>) =
match t with
| GenNode(_, []) -> 1
| GenNode(_, ls) -> 1 + sigma (map genSize ls);;
FSI> genSize tree = 5
Attempt Three - in MonoDevelop 5.9.4
Copy the code from Attempt 2 into MonoDevelop 5.9.4 and run it there and it correctly returns 6.
Question:
Could someone please explain to me what is causing the discrepancy between attempt 1 - 3?
Many thanks and kind regards.
PS: As I am currently learning F# and Functional Programming I tend to implement most of library functionality as a part of the learning process.
Stack track from Attempt 1
Assertion at sgen-alloc.c:460, condition `*p == NULL' not met
Stacktrace:
at <0xffffffff>
at (wrapper managed-to-native) object.__icall_wrapper_mono_object_new_specific (intptr) <0xffffffff>
at FSI_0002.DEL.sigma (Microsoft.FSharp.Collections.FSharpList1<int>) <0x00013>
at FSI_0002.DEL.genSize<a> (FSI_0002.DEL/genTree1) <0x0005f>
at FSI_0002.DEL/genSize#51.Invoke (FSI_0002.DEL/genTree1<a>) <0x00023>
at FSI_0002.DEL.map<FSI_0002.DEL/genTree1, int> (Microsoft.FSharp.Core.FSharpFunc2<FSI_0002.DEL/genTree1, int>,Microsoft.FSharp.Collections.FSharpList1<FSI_0002.DEL/genTree1>) <0x00032>
at FSI_0002.DEL.genSize (FSI_0002.DEL/genTree1<a>) <0x00056>
at <StartupCode$FSI_0004>.$FSI_0004.main# () <0x0001b>
at (wrapper runtime-invoke) object.runtime_invoke_void (object,intptr,intptr,intptr) <0xffffffff>
at <unknown> <0xffffffff>
at (wrapper managed-to-native) System.Reflection.MonoMethod.InternalInvoke (System.Reflection.MonoMethod,object,object[],System.Exception&) <0xffffffff>
at System.Reflection.MonoMethod.Invoke (object,System.Reflection.BindingFlags,System.Reflection.Binder,object[],System.Globalization.CultureInfo) <0x000c0>
at System.MonoType.InvokeMember (string,System.Reflection.BindingFlags,System.Reflection.Binder,object,object[],System.Reflection.ParameterModifier[],System.Globalization.CultureInfo,string[]) <0x0039a>
at System.Reflection.Emit.TypeBuilder.InvokeMember (string,System.Reflection.BindingFlags,System.Reflection.Binder,object,object[],System.Reflection.ParameterModifier[],System.Globalization.CultureInfo,string[]) <0x00066>
at System.Type.InvokeMember (string,System.Reflection.BindingFlags,System.Reflection.Binder,object,object[],System.Globalization.CultureInfo) <0x0005a>
at Microsoft.FSharp.Compiler.AbstractIL.ILRuntimeWriter/execEntryPtFun#1986-1.Invoke (Microsoft.FSharp.Core.Unit) <0x00083>
at Microsoft.FSharp.Compiler.Interactive.Shell/clo#883-37.Invoke (Microsoft.FSharp.Core.FSharpFunc2,Microsoft.FSharp.Collections.FSharpList`1<T>) <0x00038>
at Microsoft.FSharp.Collections.ListModule.Iterate<T> (Microsoft.FSharp.Core.FSharpFunc`2,Microsoft.FSharp.Collections.FSharpList`1<T>) <0x00027>
at Microsoft.FSharp.Compiler.Interactive.Shell.arg10#882 (Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompiler,Microsoft.FSharp.Collections.FSharpList`1>>,Microsoft.FSharp.Core.Unit) <0x0005b>
at Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompiler.ProcessInputs (Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompilerState,Microsoft.FSharp.Collections.FSharpList1<Microsoft.FSharp.Compiler.Ast/ParsedInput>,bool,bool,bool,Microsoft.FSharp.Collections.FSharpList1) <0x006e3>
at Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompiler.EvalParsedDefinitions (Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompilerState,bool,bool,Microsoft.FSharp.Collections.FSharpList1<Microsoft.FSharp.Compiler.Ast/SynModuleDecl>) <0x001db>
at Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompiler.EvalParsedExpression (Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompilerState,Microsoft.FSharp.Compiler.Ast/SynExpr) <0x0005f>
at Microsoft.FSharp.Compiler.Interactive.Shell/clo#1590-45.Invoke (Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompilerState) <0x012ef>
at Microsoft.FSharp.Compiler.Interactive.Shell/FsiInteractionProcessor.InteractiveCatch<a> (Microsoft.FSharp.Core.FSharpFunc22<a, Microsoft.FSharp.Compiler.Interactive.Shell/FsiInteractionStepStatus>>,a) <0x00039>
at Microsoft.FSharp.Compiler.Interactive.Shell/FsiInteractionProcessor.ExecInteraction (bool,Microsoft.FSharp.Compiler.Build/TcConfig,Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompilerState,Microsoft.FSharp.Compiler.Ast/ParsedFsiInteraction) <0x00067>
at Microsoft.FSharp.Compiler.Interactive.Shell/FsiInteractionProcessor.ExecInteractions (bool,Microsoft.FSharp.Compiler.Build/TcConfig,Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompilerState,Microsoft.FSharp.Core.FSharpOption1) <0x005fb>
at Microsoft.FSharp.Compiler.Interactive.Shell/FsiInteractionProcessor.MainThreadProcessParsedInteraction (bool,Microsoft.FSharp.Core.FSharpOption1<Microsoft.FSharp.Compiler.Ast/ParsedFsiInteraction>,Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompilerState) <0x0013b>
at Microsoft.FSharp.Compiler.Interactive.Shell/res#1782.Invoke (Microsoft.FSharp.Compiler.Interactive.Shell/FsiDynamicCompilerState) <0x00033>
at Microsoft.FSharp.Compiler.Interactive.Shell/runCodeOnMainThread#2021-2.Invoke (Microsoft.FSharp.Core.Unit) <0x0003b>
at <StartupCode$FSharp-Compiler-Interactive-Settings>.$Fsiaux/Microsoft-FSharp-Compiler-Interactive-IEventLoop-Invoke#47.Invoke (Microsoft.FSharp.Core.Unit) <0x0001a>
at <StartupCode$FSharp-Compiler-Interactive-Settings>.$Fsiaux/run#38-4.Invoke (Microsoft.FSharp.Core.FSharpFunc2) <0x00039>
at Microsoft.FSharp.Primitives.Basics.List.iter (Microsoft.FSharp.Core.FSharpFunc2<T, Microsoft.FSharp.Core.Unit>,Microsoft.FSharp.Collections.FSharpList1) <0x00038>
at Microsoft.FSharp.Collections.ListModule.Iterate (Microsoft.FSharp.Core.FSharpFunc2<T, Microsoft.FSharp.Core.Unit>,Microsoft.FSharp.Collections.FSharpList1) <0x00027>
at .$Fsiaux.run#35 (Microsoft.FSharp.Compiler.Interactive.SimpleEventLoop,Microsoft.FSharp.Core.Unit) <0x000d3>
at Microsoft.FSharp.Compiler.Interactive.SimpleEventLoop.Microsoft-FSharp-Compiler-Interactive-IEventLoop-Run () <0x0001f>
at Microsoft.FSharp.Compiler.Interactive.Shell.runLoop#2066 (Microsoft.FSharp.Compiler.Interactive.Shell/FsiConsoleOutput,Microsoft.FSharp.Core.Unit) <0x00205>
at Microsoft.FSharp.Compiler.Interactive.Shell.DriveFsiEventLoop (Microsoft.FSharp.Compiler.Interactive.Shell/FsiConsoleOutput) <0x0001b>
at Microsoft.FSharp.Compiler.Interactive.Shell/FsiEvaluationSession.Run () <0x00bfb>
at Microsoft.FSharp.Compiler.Interactive.Shell.evaluateSession#2382 (string[],Microsoft.FSharp.Core.Unit) <0x0009b>
at Microsoft.FSharp.Compiler.Interactive.Shell.MainMain (string[]) <0x00123>
at Microsoft.FSharp.Compiler.Interactive.Main.FsiMain (string[]) <0x00013>
at (wrapper runtime-invoke) .runtime_invoke_int_object (object,intptr,intptr,intptr) <0xffffffff>
Native stacktrace:
mono() [0x8102a23]
[0xb775240c]
[0xb7752424]
/lib/i386-linux-gnu/libc.so.6(gsignal+0x47) [0xb7545607]
/lib/i386-linux-gnu/libc.so.6(abort+0x143) [0xb7548a33]
mono() [0x827b381]
mono() [0x827b508]
mono() [0x827b5a3]
mono() [0x8233338]
mono() [0x8233a4c]
mono() [0x81f20a8]
mono(mono_object_new_alloc_specific+0x40) [0x81f6570]
mono(mono_object_new_specific+0x88) [0x81f6628]
[0xb725cc71]
[0xb25a974c]
[0xb25a9640]
[0xb25a9724]
[0xb25a96c3]
[0xb25a9637]
[0xb25a94ac]
[0xb725b5f7]
mono() [0x80723d1]
Debug info from gdb:
Could not attach to process. If your uid matches the uid of the target
process, check the setting of /proc/sys/kernel/yama/ptrace_scope, or try
again as the root user. For more details, see /etc/sysctl.d/10-ptrace.conf
ptrace: Operation not permitted.
No threads.
=================================================================
Got a SIGABRT while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.
Aborted
Looks like a Mono bug. I tested in both VS2013 and VS2015 and your code works just fine. If you can grab the stack trace I would file a bug with the Mono guys.
I get the same stack trace as you. For the record by Mono version is
Mono JIT compiler version 4.0.2 ((detached/c99aa0c Thu Jun 11 18:53:01 EDT 2015)
If you Google "Assertion at sgen-alloc.c:460, condition `*p == NULL' not met" you will see a few references to this error with Mono.
EDIT: Tested on Mono 4.0.3 and it has the same issue. Whats interesting is if you make genTree non generic like
type genTree = GenNode of string * genTree list
it works perfectly.

Error when calling ToListAsync() method of Windows Azure Mobile service using mvvmcross in Android

I am building an app with AzureMobile Services in mvvmcross when I call ToListAsync() method for retrieving data from server in Windows Phone 8 it works fine but there is an error in Xamarin.Android. Any one suggest me to resolve the issue.
Here is a full error stack
mvx:Warning: 39.64 Exception masked AggregateException:
12-02 14:06:53.317 I/mono-stdout( 2032): mvx:Warning: 39.64 Exception masked AggregateException:
at System.Threading.Tasks.Task`1[System.Collections.Generic.List`1[EmployeeDirectoryCross.Core.Models.Employee]].get_Result () [0x00000] in <filename unknown>:0
12-02 14:06:53.326 I/mono-stdout( 2032): at System.Threading.Tasks.Task`1[System.Collections.Generic.List`1[EmployeeDirectoryCross.Core.Models.Employee]].get_Result () [0x00000] in <filename unknown>:0
12-02 14:06:53.335 I/mono-stdout( 2032): at EmployeeDirectoryCross.Core.ViewModels.EmployeeListViewModel+<>c__DisplayClass2.<SearchEmployees>b__1 () [0x00001] in e:\Study\Xamarin\XamrinSamples\EmployeeDirectoryCross\EmployeeDirectoryCross.Core\ViewModels\EmployeeListViewModel.cs:54
12-02 14:06:53.335 D/Mono ( 2032): Unloading image System.dll [0x2b365118].
12-02 14:06:53.335 D/Mono ( 2032): Image addref System[0x2b354bf8] -> System.dll[0x2a6189d8]: 18
at EmployeeDirectoryCross.Core.ViewModels.EmployeeListViewModel+<>c__DisplayClass2.<SearchEmployees>b__1 () [0x00001] in e:\Study\Xamarin\XamrinSamples\EmployeeDirectoryCross\EmployeeDirectoryCross.Core\ViewModels\EmployeeListViewModel.cs:54
12-02 14:06:53.355 I/mono-stdout( 2032): at Cirrious.CrossCore.Core.MvxMainThreadDispatcher.ExceptionMaskedAction (System.Action action) [0x00000] in <filename unknown>:0
at Cirrious.CrossCore.Core.MvxMainThreadDispatcher.ExceptionMaskedAction (System.Action action) [0x00000] in <filename unknown>:0
12-02 14:06:53.355 I/mono-stdout( 2032): InnerException was MobileServiceInvalidOperationException: The server did not provide a response with the expected content.
InnerException was MobileServiceInvalidOperationException: The server did not provide a response with the expected content.
at Microsoft.WindowsAzure.MobileServices.MobileServiceHttpClient+<SendRequestAsync>d__1c.MoveNext () [0x00000] in <filename unknown>:0
12-02 14:06:53.355 I/mono-stdout( 2032): at Microsoft.WindowsAzure.MobileServices.MobileServiceHttpClient+<SendRequestAsync>d__1c.MoveNext () [0x00000] in <filename unknown>:0
--- End of stack trace from previous location where exception was thrown ---
12-02 14:06:53.355 I/mono-stdout( 2032): --- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x00000] in <filename unknown>:0
12-02 14:06:53.365 I/mono-stdout( 2032): at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x00000] in <filename unknown>:0
12-02 14:06:53.365 I/mono-stdout( 2032): at System.Runtime.CompilerServices.TaskAwaiter`1[System.Net.Http.HttpResponseMessage].GetResult () [0x00000] in <filename unknown>:0
at System.Runtime.CompilerServices.TaskAwaiter`1[System.Net.Http.HttpResponseMessage].GetResult () [0x00000] in <filename unknown>:0
12-02 14:06:53.385 I/mono-stdout( 2032): at Microsoft.WindowsAzure.MobileServices.MobileServiceHttpClient+<RequestAsync>d__4.MoveNext () [0x00000] in <filename unknown>:0

Resources