ICorDebugGCReferenceEnum.Next fails to return stack references in .NET 8 preview 4

[gregg-miskelly]

Description

.NET 8 preview 4 seems to have a regression that ICorDebugGCReferenceEnum.Next is no longer returning stack references

Reproduction Steps

1. Create the following program
2. Using Visual Studio, set a breakpoint where indicated
3. When the breakpoint is hit, take a heap snapshot from the Diagnostics tools window
4. View the snapshot

class MyStringHolder
{
    public readonly string Value;

    public MyStringHolder(string value)
    {
        Value = value;
    }
}

class Program
{
    public static void Main()
    {
        var bigString = new MyStringHolder(new string('*', 1000000));

        Console.WriteLine(bigString.Value.Length); // breakpoint here
    }
}

Expected behavior

'MyStringHolder' should be shown as having the largest inclusive size

Actual behavior

ICorDebugGCReferenceEnum.Next is not returning values for all of the stack variables (references with type CorReferenceStack). I see some from the hot reload thread, but none from the 'Main' function.

Regression?

This worked correctly in .NET 8 preview 3

Known Workarounds

No response

Configuration

I am testing with .NET 8 preview 4 on Windows. Both x86 and x64. I didn't test any other architecture or OS.

Other information

No response

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Issue Details

---

Description

.NET 8 preview 4 seems to have a regression that ICorDebugGCReferenceEnum.Next is no longer returning stack references

Reproduction Steps

1. Create the following program
2. Using Visual Studio, set a breakpoint where indicated
3. When the breakpoint is hit, take a heap snapshot from the Diagnostics tools window
4. View the snapshot

class MyStringHolder
{
    public readonly string Value;

    public MyStringHolder(string value)
    {
        Value = value;
    }
}

class Program
{
    public static void Main()
    {
        var bigString = new MyStringHolder(new string('*', 1000000));

        Console.WriteLine(bigString.Value.Length); // breakpoint here
    }
}

Expected behavior

'MyStringHolder' should be shown as having the largest inclusive size

Actual behavior

ICorDebugGCReferenceEnum.Next is not returning any references with type CorReferenceStack, so visual studio believes the object is dead.

Regression?

This worked correctly in .NET 8 preview 3

Known Workarounds

No response

Configuration

I am testing with .NET 8 preview 4 on Windows. Both x86 and x64. I didn't test any other architecture or OS.

Other information

No response

Author:	gregg-miskelly
Assignees:	-
Labels:	area-Diagnostics-coreclr, untriaged
Milestone:	-

[tommcdon]

@hoyosjs

[leculver]

Maybe: #92313