UnsafeAccessor with generic struct segfault

[andykernahan]

Description

Runtime segfaults (exit code 139) when using UnsafeAccessor to invoke method on generic struct constructed with class type.

Reproduction Steps

Given:

using System.Runtime.CompilerServices;

S<int> sInt32 = new();
Accessor<int>.M(ref sInt32);
Console.WriteLine("Int32 okay");

S<string> sString = new();
Accessor<string>.M(ref sString);
Console.WriteLine("string okay");

public struct S<T>
{
    private void M() { }
}

public static class Accessor<T>
{
    [UnsafeAccessor(UnsafeAccessorKind.Method, Name = "M")]
    public static extern void M(ref S<T> s);
}

Then:

$ dotnet run Program.cs 
Int32 okay
$ echo $?
139

Expected behavior

Does not segfault and prints string okay.

Actual behavior

Segfaults (exit code 139).

Regression?

No response

Known Workarounds

No response

Configuration

dotnet --info
.NET SDK:
 Version:           10.0.101
 Commit:            fad253f51b
 Workload version:  10.0.100-manifests.c57ac48b
 MSBuild version:   18.0.6+fad253f51

Runtime Environment:
 OS Name:     Mac OS X
 OS Version:  26.1
 OS Platform: Darwin
 RID:         osx-arm64
 Base Path:   /usr/local/share/dotnet/sdk/10.0.101/

.NET workloads installed:
There are no installed workloads to display.
Configured to use workload sets when installing new manifests.
No workload sets are installed. Run "dotnet workload restore" to install a workload set.

Host:
  Version:      10.0.1
  Architecture: arm64
  Commit:       fad253f51b

.NET SDKs installed:
  10.0.100 [/usr/local/share/dotnet/sdk]
  10.0.101 [/usr/local/share/dotnet/sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 10.0.1 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 10.0.1 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]

Other architectures found:
  None

Environment variables:
  Not set

global.json file:
  Not found

Other information

No response

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