[release/5.0] P/Invoke function returning SafeSocketHandle throws MissingMethodException (#45911)

[eerhardt]

Description

The ILLinker is trimming the private default constructors of SafeHandle classes if they are not used by the library. Adding an XML descriptor file to preserve the private constructors of these SafeHandles so they can be used in P/Invokes in external code.

Customer Impact

If an app is using SafeSocketHandle as the return of a P/Invoke and upgrades from 3.1 to 5.0, the app is broken with System.MissingMethodException: .ctor. There isn't a workaround other than not using SafeSocketHandle in the P/Invoke signature.

Testing

Added 2 new tests for the SafeHandles identified as problematic to ensure customers can P/Invoke using these classes.

Risk

Low

Fix #45633

[ghost]

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Issue Details

---

Description

The ILLinker is trimming the private default constructors of SafeHandle classes if they are not used by the library. Adding an XML descriptor file to preserve the private constructors of these SafeHandles so they can be used in P/Invokes in external code.

Customer Impact

If an app is using SafeSocketHandle as the return of a P/Invoke and upgrades from 3.1 to 5.0, the app is broken with System.MissingMethodException: .ctor. There isn't a workaround other than not using SafeSocketHandle in the P/Invoke signature.

Testing

Added 2 new tests for the SafeHandles identified as problematic to ensure customers can P/Invoke using these classes.

Risk

Low

Fix #45633

Author:	eerhardt
Assignees:	eerhardt
Labels:	area-System.Net.Sockets, regression-from-last-release
Milestone:	-

[jeffschwMSFT]

Approved. We should consider this for 5.0.2

[eerhardt]

This is broken in the release/5.0 branch because of some build infrastructure differences between master and release/5.0. (Thank you, tests!)

Working on a fix.

[eerhardt]

The single test failure is #43981.

    System.Threading.Tests.ThreadLocalTests.RunThreadLocalTest8_Values [FAIL]
      System.Threading.Tasks.TaskSchedulerException : An exception was thrown by a TaskScheduler.
      ---- System.ExecutionEngineException : Couldn't create thread. Error 0x0
      Stack Trace:
        /_/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs(1696,0): at System.Threading.Tasks.Task.ScheduleAndStart(Boolean needsProtection)
        /_/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Future.cs(333,0): at System.Threading.Tasks.Task`1[[System.Int32, System.Private.CoreLib, Version=5.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].StartNew(Task parent, Func`1 function, CancellationToken cancellationToken, TaskCreationOptions creationOptions, InternalTaskOptions internalOptions, TaskScheduler scheduler)
        /_/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/TaskFactory.cs(629,0): at System.Threading.Tasks.TaskFactory.StartNew[Int32](Func`1 function, CancellationToken cancellationToken, TaskCreationOptions creationOptions, TaskScheduler scheduler)
        /_/src/libraries/System.Threading/tests/ThreadLocalTests.cs(253,0): at System.Threading.Tests.ThreadLocalTests.RunThreadLocalTest8_Values()
        /_/src/mono/netcore/System.Private.CoreLib/src/System/Reflection/RuntimeMethodInfo.cs(384,0): at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
        ----- Inner Stack Trace -----
        /_/src/mono/netcore/System.Private.CoreLib/src/System/Threading/Thread.Mono.cs(265,0): at System.Threading.Thread.Start(Object parameter)
        /_/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/ThreadPoolTaskScheduler.cs(50,0): at System.Threading.Tasks.ThreadPoolTaskScheduler.QueueTask(Task task)
        /_/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/TaskScheduler.cs(237,0): at System.Threading.Tasks.TaskScheduler.InternalQueueTask(Task task)
        /_/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs(1668,0): at System.Threading.Tasks.Task.ScheduleAndStart(Boolean needsProtection)
  Finished:    System.Threading.Tests
=== TEST EXECUTION SUMMARY ===