ClrMD is not working from within a .NET 6 single-file application on Windows

[5teveb]

This was working for me in .NET 5. A simple program can show the problem:

using Microsoft.Diagnostics.Runtime;
using System;
using System.Diagnostics;
using System.Linq;

namespace ClrMDTest
{
    internal class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Attempt to list threads:");

            DataTarget target = null;
            try
            {
                target = DataTarget.CreateSnapshotAndAttach(Process.GetCurrentProcess().Id);
                ClrRuntime runtime = target.ClrVersions.First().CreateRuntime();
                foreach (ClrThread thread in runtime.Threads)
                {
                    Console.WriteLine($"ID:{thread.ManagedThreadId} Background:{thread.IsBackground} Alive:{thread.IsAlive}");                    
                }
            }
            catch(Exception ex)
            {
                Console.WriteLine($"Failed with exception: {ex}");
            }
            finally
            {
                target.Dispose();
            }

            Console.Read();
        }
    }
}

For .NET 5 the publish profile is:

<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <PropertyGroup>
    <Configuration>Release</Configuration>
    <Platform>Any CPU</Platform>
    <PublishDir>bin\Release\net5.0\publish\win-x64\</PublishDir>
    <PublishProtocol>FileSystem</PublishProtocol>
    <TargetFramework>net5.0</TargetFramework>
    <RuntimeIdentifier>win-x64</RuntimeIdentifier>
    <SelfContained>true</SelfContained>
    <PublishSingleFile>True</PublishSingleFile>
    <PublishReadyToRun>False</PublishReadyToRun>
    <IncludeAllContentForSelfExtract>True</IncludeAllContentForSelfExtract>
  </PropertyGroup>
</Project>

With .NET 5 I get the following output:

Attempt to list threads:
ID:1 Background:False Alive:True
ID:2 Background:True Alive:True
ID:3 Background:True Alive:True

For .NET 6 the publish profile is:

<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <PropertyGroup>
    <Configuration>Release</Configuration>
    <Platform>Any CPU</Platform>
    <PublishDir>bin\Release\net6.0\publish\win-x64\</PublishDir>
    <PublishProtocol>FileSystem</PublishProtocol>
    <TargetFramework>net6.0</TargetFramework>
    <RuntimeIdentifier>win-x64</RuntimeIdentifier>
    <SelfContained>true</SelfContained>
    <PublishSingleFile>True</PublishSingleFile>
    <PublishReadyToRun>False</PublishReadyToRun>
    <IncludeAllContentForSelfExtract>True</IncludeAllContentForSelfExtract>
  </PropertyGroup>
</Project>

For .NET 6 I get the following output:

Attempt to list threads:
Failed with exception: System.InvalidOperationException: Sequence contains no elements
   at System.Linq.ThrowHelper.ThrowNoElementsException()
   at ClrMDTest.Program.Main(String[] args)

I used VS2022 for this program.

Microsoft Windows [Version 10.0.19044.1466]
(c) Microsoft Corporation. All rights reserved.

H:\>dotnet --info
.NET SDK (reflecting any global.json):
 Version:   6.0.101
 Commit:    ef49f6213a

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.19044
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\6.0.101\

Host (useful for support):
  Version: 6.0.1
  Commit:  3a25a7f1cc

.NET SDKs installed:
  2.1.200 [C:\Program Files\dotnet\sdk]
  2.1.201 [C:\Program Files\dotnet\sdk]
  2.1.202 [C:\Program Files\dotnet\sdk]
  2.1.400 [C:\Program Files\dotnet\sdk]
  2.1.402 [C:\Program Files\dotnet\sdk]
  2.1.403 [C:\Program Files\dotnet\sdk]
  2.1.526 [C:\Program Files\dotnet\sdk]
  2.2.101 [C:\Program Files\dotnet\sdk]
  3.1.302 [C:\Program Files\dotnet\sdk]
  3.1.416 [C:\Program Files\dotnet\sdk]
  5.0.101 [C:\Program Files\dotnet\sdk]
  5.0.202 [C:\Program Files\dotnet\sdk]
  5.0.403 [C:\Program Files\dotnet\sdk]
  5.0.404 [C:\Program Files\dotnet\sdk]
  6.0.101 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.All 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.15 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.22 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.2.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.15 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.22 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.2.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.19 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.21 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.22 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.12 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.0.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.15 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.22 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.2.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.19 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.21 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.22 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.12 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.1.6 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.11 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.19 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.21 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.22 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.11 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.12 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.13 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 6.0.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET runtimes or SDKs:
  https://aka.ms/dotnet-download

H:\>

It would be nice to see this working again. I've used it in real programs to list the stack traces for all threads to a file. This allows me to have users send me a simple text file which along with other information on our app has the stack traces which helps in diagnosing deadlocks.

[mikem8361]

What version of clrmd are you using? The latest on nuget: 2.0.226801?

[5teveb]

Yes, that's the one:

<PackageReference Include="Microsoft.Diagnostics.Runtime" Version="2.0.226801" />

[leculver]

AFAIK this is actually due to an issue with create-dump, not with ClrMD. See this issue: dotnet/diagnostics#3065.

When I last debugged this, there was not enough data being placed into the crash dump for any debugger to make sense of single-file dumps (ClrMD included). I'm happy to take a closer look if you find that's not the case.

[5teveb]

I noticed in the issue linked to by @leculver (dotnet/diagnostics#3065) that near the end of the discussion there that @mikem8361 mentions that:

"It is against Windows policy to ship/redistribute the fixed dbghelp/dbgcore/dbgeng with dotnet-dump. This fix will shipping in a future Windows service release."

Well it seems that this has happened as the problem I was seeing has 'self healed' without me even having to recompile my test program!

Thanks for fixing this. I'm unsure if I should close this myself (since it wasn't me who did the hard work of fixing the problem) so I'll leave the issue open so that the right person can close this with a suitable comment.