Maui iOS app crashes on startup on real devices: "Attempting to JIT compile method.....while running in aot-only mode"

[drewrobey]

Package

Sentry

.NET Flavor

.NET

.NET Version

9

OS

iOS

OS Version

No response

Development Environment

Visual Studio v17.x

SDK Version

5.5.1

Self-Hosted Sentry Version

No response

Workload Versions

UseSentry or SentrySdk.Init call

.UseSentry(options =>
{
options.Dsn = "REMOVED";

#if DEBUG
options.Debug = true;

                options.TracesSampleRate = 1.0;

#else
options.TracesSampleRate = 0.2;
#endif

                options.IsGlobalModeEnabled = true;
                options.IncludeTextInBreadcrumbs = true;
                options.IncludeTitleInBreadcrumbs = true;
                options.IncludeBackgroundingStateInBreadcrumbs = true;
                options.AttachStacktrace = true;
                options.CaptureFailedRequests = true;
            });

Steps to Reproduce

1. Create Maui Project
2. Add Sentry
3. Build and release for iOS
4. Install via Testflight on real device
5. App will crash on startup

Expected Result

App should run.

Actual Result

Here's the exception, which seems to indicate Sentry is trying to JIT-compile something at runtime (via DynamicMethod) on iOS, which is strictly Ahead-Of-Time compiled. iOS forbids runtime JIT, but Android allows it, so the app works on Android and crashes on iOS:

Attempting to JIT compile method '(wrapper dynamic-method) object object:InvokeStub_SafeDigestCtxHandle..ctor (object,object,intptr*)' while running in aot-only mode. See https://learn.microsoft.com/xamarin/ios/internals/limitations

for more information.
(System.ExecutionEngineException)
at System.Delegate.CreateDelegate(Type type, Object firstArgument, MethodInfo method, Boolean throwOnBindFailure, Boolean allowClosed)
at System.Reflection.Emit.DynamicMethod.CreateDelegate(Type , Object )
at System.Reflection.InvokerEmitUtil.CreateInvokeDelegate_RefArgs(MethodBase , Boolean )
at System.Reflection.MethodInvokerCommon.DetermineStrategy_RefArgs(InvokerStrategy& , InvokeFunc_RefArgs& , MethodBase , Boolean )
at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object , BindingFlags )
at System.RuntimeType.CreateInstanceMono(Boolean , Boolean )
at System.Activator.CreateInstanceSafeDigestCtxHandle
at System.Runtime.InteropServices.Marshalling.SafeHandleMarshaller`1.ManagedToUnmanagedOut[[System.Security.Cryptography.Apple.SafeDigestCtxHandle, System.Security.Cryptography, Version=9.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a]]..ctor()
at Interop.AppleCrypto.DigestCreate(PAL_HashAlgorithm , Int32& )
at System.Security.Cryptography.LiteHash..ctor(PAL_HashAlgorithm )
at System.Security.Cryptography.HashProviderDispenser.CreateHashProvider(String )
at System.Security.Cryptography.SHA1.Implementation..ctor()
at System.Security.Cryptography.SHA1.Create()
at Sentry.Internal.Extensions.HashExtensions.GetHashString(String , Boolean )
at Sentry.SentryOptions.TryGetDsnSpecificCacheDirectoryPath()
at Sentry.Internal.Http.CachingTransport..ctor(ITransport , SentryOptions , Boolean )
at Sentry.Internal.Http.CachingTransport.Create(ITransport , SentryOptions , Boolean , Boolean )
at Sentry.Internal.SdkComposer.CreateTransport()
at Sentry.Internal.SdkComposer.CreateBackgroundWorker()
at Sentry.SentryClient..ctor(SentryOptions , IBackgroundWorker , RandomValuesFactory , ISessionManager )
at Sentry.Internal.Hub..ctor(SentryOptions , ISentryClient , ISessionManager , ISystemClock , IInternalScopeManager , RandomValuesFactory )
at Sentry.SentrySdk.InitHub(SentryOptions )
at Sentry.SentrySdk.Init(SentryOptions )
at Sentry.Maui.Internal.SentryMauiInitializer.Initialize(IServiceProvider )
at Microsoft.Maui.MauiContextExtensions.InitializeAppServices(MauiApp mauiApp)
at Microsoft.Maui.Hosting.MauiAppBuilder.Build()
at MYPROJECTNAME.MauiProgram.CreateMauiApp()
at MYPROJECTNAME.AppDelegate.CreateMauiApp()
at Microsoft.Maui.MauiUIApplicationDelegate.WillFinishLaunching(UIApplication application, NSDictionary launchOptions)
at Microsoft.Maui.MauiUIApplicationDelegate.Registrar_Callbacks.callback_796_Microsoft_Maui_MauiUIApplicationDelegate_WillFinishLaunching(IntPtr pobj, IntPtr sel, IntPtr p0, IntPtr p1, IntPtr* exception_gchandle)

[aritchie]

@drewrobey Can you please include your csproj build options around AOT & Trimming or a small reproducible sample?

[bruno-garcia]

As @aritchie said, we really need the AOT and Trimming options at a minimum to know what's going on and a repro would make everything much faster.

But looking at it, this is really odd. Sentry is using .NET's SHA1 to has the DSN in order to get a file path for caching events on disk:

at Interop.AppleCrypto.DigestCreate(PAL_HashAlgorithm , Int32& )
at System.Security.Cryptography.LiteHash..ctor(PAL_HashAlgorithm )
at System.Security.Cryptography.HashProviderDispenser.CreateHashProvider(String )
at System.Security.Cryptography.SHA1.Implementation..ctor()
at System.Security.Cryptography.SHA1.Create()
at Sentry.Internal.Extensions.HashExtensions.GetHashString(String , Boolean )
at Sentry.SentryOptions.TryGetDsnSpecificCacheDirectoryPath()
at Sentry.Internal.Http.CachingTransport..ctor(ITransport , SentryOptions , Boolean )

But somehow that goes into an interop with Apple's Crypto API that ends up on System.Reflection.Emit.DynamicMethod.CreateDelegate which obviously will fail on iOS in release mode.

Some thoughts of work around:

1. Disable offline caching on iOS - Just a quick work around to fix the crash right now while keeping Sentry.
2. On iOS we already have sandboxing of app files (so it won't get mixed with other apps). So we could skip the DSN hash when composing the file path.
3. Figure out why .NET on iOS is blowing up when using SHA1 and fix/work around that (ideally we do this)

[drewrobey]

@aritchie @bruno-garcia

The build options we're using are the standard iOS ones:

• Link Framework SDKs only
• Use the LLVM optimizing compiler in release mode
• AOT is on

Please find attached a repro project, which is just the Maui sample project with Sentry included and some simple Sentry config.

TestApp.zip

[drewrobey]

Due to my lack of knowledge of Sentry's inner workings, I've had to resort to ChatGPT for advice on this (I say whilst shuddering). It recommends including:

options.CacheDirectoryPath = null; //Disables caching

as a potential work-around. @bruno-garcia is this the sort of thing you were referring to?

[jamescrosswell]

options.CacheDirectoryPath = null; //Disables caching

It looks like ChatGPT got that one right!

This is the source code corresponding to the stack trace:

sentry-dotnet/src/Sentry/Internal/Extensions/HashExtensions.cs

Line 8 in e827b76

using var sha = SHA1.Create();

Honestly I wonder whether we should write our own hash implementation - we've had so many issues with the ones from the runtime and the only reason we're using this is to generate a unique directory name (we don't need cryptographic hashing algorithms for this).