iOS: Attempting to JIT compile method '(wrapper dynamic-method) string object:lambda_method1 (System.Runtime.CompilerServices.Closure)' while running in aot-only mode.

[rolfbjarne]

Description

The following code throws an exception at runtime when running on an iOS device:

var foos = new string [] { "hi", "bye" };
string f = foos.AsQueryable ().First ();

Exception:

System.ExecutionEngineException: Attempting to JIT compile method '(wrapper dynamic-method) string object:lambda_method1 (System.Runtime.CompilerServices.Closure)' while running in aot-only mode. See https://docs.microsoft.com/xamarin/ios/internals/limitations for more information.
    at System.Delegate.CreateDelegate(Type type, Object firstArgument, MethodInfo method, Boolean throwOnBindFailure, Boolean allowClosed)
    at System.Delegate.CreateDelegate(Type type, Object firstArgument, MethodInfo method, Boolean throwOnBindFailure)
    at System.Delegate.CreateDelegate(Type type, Object firstArgument, MethodInfo method)
    at System.Reflection.Emit.DynamicMethod.CreateDelegate(Type delegateType, Object target)
    at System.Linq.Expressions.Compiler.LambdaCompiler.CreateDelegate()
    at System.Linq.Expressions.Compiler.LambdaCompiler.Compile(LambdaExpression lambda)
    at System.Linq.Expressions.Expression`1[[System.Func`1[[System.String, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].Compile()
    at System.Linq.EnumerableExecutor`1[[System.String, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].Execute()
    at System.Linq.EnumerableQuery`1[[System.String, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].System.Linq.IQueryProvider.Execute[String](Expression expression)
    at System.Linq.Queryable.First[String](IQueryable`1 source)
    at MySingleView.AppDelegate.FinishedLaunching(UIApplication app, NSDictionary options) in /Users/rolf/work/maccore/onedotnet/xamarin-macios/tests/dotnet/MySingleView/AppDelegate.cs:line 27

Repro:

git clone https://github.com/rolfbjarne/xamarin-macios
cd xamarin-macios
git checkout dotnet-attempting-to-jit-compile-method-lamba_method1
./configure --enable-dotnet
make reset
make all -j8
make install -j8
make mysingleview -C tests/dotnet

Complete output

Configuration

.NET 6.0.100-alpha.1.21060.3

Binlog:
MySingleView.binlog.zip

Regression?

No (new feature)

[ghost]

Tagging subscribers to this area: @cston
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Description

The following code throws an exception at runtime when running on an iOS device:

var foos = new string [] { "hi", "bye" };
string f = foos.AsQueryable ().First ();

Exception:

System.ExecutionEngineException: Attempting to JIT compile method '(wrapper dynamic-method) string object:lambda_method1 (System.Runtime.CompilerServices.Closure)' while running in aot-only mode. See https://docs.microsoft.com/xamarin/ios/internals/limitations for more information.
    at System.Delegate.CreateDelegate(Type type, Object firstArgument, MethodInfo method, Boolean throwOnBindFailure, Boolean allowClosed)
    at System.Delegate.CreateDelegate(Type type, Object firstArgument, MethodInfo method, Boolean throwOnBindFailure)
    at System.Delegate.CreateDelegate(Type type, Object firstArgument, MethodInfo method)
    at System.Reflection.Emit.DynamicMethod.CreateDelegate(Type delegateType, Object target)
    at System.Linq.Expressions.Compiler.LambdaCompiler.CreateDelegate()
    at System.Linq.Expressions.Compiler.LambdaCompiler.Compile(LambdaExpression lambda)
    at System.Linq.Expressions.Expression`1[[System.Func`1[[System.String, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].Compile()
    at System.Linq.EnumerableExecutor`1[[System.String, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].Execute()
    at System.Linq.EnumerableQuery`1[[System.String, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].System.Linq.IQueryProvider.Execute[String](Expression expression)
    at System.Linq.Queryable.First[String](IQueryable`1 source)
    at MySingleView.AppDelegate.FinishedLaunching(UIApplication app, NSDictionary options) in /Users/rolf/work/maccore/onedotnet/xamarin-macios/tests/dotnet/MySingleView/AppDelegate.cs:line 27

Repro:

git clone https://github.com/rolfbjarne/xamarin-macios
cd xamarin-macios
git checkout dotnet-attempting-to-jit-compile-method-lamba_method1
./configure --enable-dotnet --enable-xamarin
make reset
make all -j8
make install -j8
make mysingleview -C tests/dotnet

Complete output

Configuration

.NET 6.0.100-alpha.1.21060.3

Binlog:
MySingleView.binlog.zip

Regression?

No (new feature)

Author:	rolfbjarne
Assignees:	-
Labels:	area-System.Linq.Expressions, untriaged
Milestone:	-

[EgorBo]

I suspect LambdaCompiler should always prefer interpretation instead of compilation on iOS.

https://github.com/dotnet/runtime/blob/master/src/libraries/System.Linq.Expressions/src/System.Linq.Expressions.csproj#L6-L9

[steveisok]

@MaximLipnin See if you can reproduce and give Egor's suggestion a try after.

[MaximLipnin]

I faced a lot of library test failures with similar error in in #50510. I have no any ios device at hand so I'll try re-enabling System.Linq.Expresions test suite in the PR and see any related CI failures.

[steveisok]

@MaximLipnin try testing against the simulator with aot enabled. You should be able to take Rolf's example and alter the functional test to repro.

[MaximLipnin]

It's reproducible against the simulator when executing

1. ./build.sh -os iOSSimulator -arch x64 -c Release -s mono+libs
2. ./dotnet.sh build /t:Test /p:TargetOS=iOSSimulator /p:TargetArchitecture=x64 /p:Configuration=Release /p:RunAOTCompilation=true  /p:EnableAggressiveTrimming=true src/tests/FunctionalTests/iOS/Simulator/AOT/iOS.Simulator.Aot.Test.csproj

@EgorBo What would be the right way to apply your suggestion? When trying to set <IsInterpreting>true</IsInterpreting>
I get the following error:

/Users/maxim/.nuget/packages/microsoft.dotnet.apicompat/6.0.0-beta.21321.1/build/Microsoft.DotNet.ApiCompat.targets(145,5): error : TypesMustExist : Type 'System.Linq.Expressions.ExpressionCreator<TDelegate>' does not exist in the reference but it does exist in the implementation. [/Users/maxim/dev/runtime/src/libraries/System.Linq.Expressions/src/System.Linq.Expressions.csproj]
/Users/maxim/.nuget/packages/microsoft.dotnet.apicompat/6.0.0-beta.21321.1/build/Microsoft.DotNet.ApiCompat.targets(159,5): error : MatchingRefApiCompat failed - The reference assembly doesn't match all the APIs in the implementation for '/Users/maxim/dev/runtime/artifacts/bin/System.Linq.Expressions/net6.0-Release/System.Linq.Expressions.dll'. To address either fix errors in the reference assembly (referenced as implementation in compat errors for this reverse compat check), add the issues to the baseline file '/Users/maxim/dev/runtime/src/libraries/System.Linq.Expressions/src/MatchingRefApiCompatBaseline.txt' or disable this check by setting RunMatchingRefApiCompat=false in this project. [/Users/maxim/dev/runtime/src/libraries/System.Linq.Expressions/src/System.Linq.Expressions.csproj]

The System.Linq.Expressions.ExpressionCreator type is not in the reference assembly.

[steveisok]

@ViktorHofer Not quite sure who to ask, but would you happen to know the answer to Maxim's question?

[EgorBo]

@MaximLipnin I guess nobody tested "true" for that condition and it doesn't expose the same public APIs when it's set.
if the only error AppCompat found is

error : TypesMustExist : Type 'System.Linq.Expressions.ExpressionCreator<TDelegate>' does not exist in the reference but it does exist in the implementation. [/Users/maxim/dev/runtime/src/libraries/System.Linq.Expressions/src/System.Linq.Expressions.csproj]

that should not be difficult to fix

[ViktorHofer]

I guess nobody tested "true" for that condition and it doesn't expose the same public APIs when it's set.
if the only error AppCompat found is

Right, we had that option enabled on some configurations (I believe uap) which don't exist anymore. Nobody noticed that the API surface diverged when using the interpreter mode.