Calling AssemblyLoadContext.Unload multiple times causes fatal crash  #91087

Description

@maxima120

Description

Unfortunately I cant provide repro case (yet). But at least it is reproducible every time I try certain scenario in my app.

I am getting this exception in WPF .NET 7 app. It happens when I try to unload a dll loaded in run-time.. The unload works if called correctly.

But if it tries to call apploadingContext.Unload second time (there is a bug somewhere in my code) - the exception ExecutionEngineException is shown in VS if I debug and if I run it standalone I get this error in event log:

Faulting application name: qqq.exe, version: 0.4.0.1, time stamp: 0x64b07659
Faulting module name: coreclr.dll, version: 7.0.1023.36312, time stamp: 0x64b06d6c
Exception code: 0xc0000005
Fault offset: 0x0000000000133fa2
Faulting process ID: 0xaea4
Faulting application start time: 0x01d9d69df3fe6c1e
Faulting application path: qqqq\bin\Debug\net7.0-windows\qqq.exe
Faulting module path: C:\Program Files\dotnet\shared\Microsoft.NETCore.App\7.0.10\coreclr.dll
Report ID: 9616639b-d2b2-4669-95da-65f25f23f4e7
Faulting package full name: Faulting package-relative application ID: 

Reproduction Steps

N/A

Expected behavior

Since this exception marked as obsolete I think it should not be thrown. Perhaps new design should react on fatal conditions somehow differently.. Having said that I want to point that dll I am loading is few lines C# compiled in run-time with Roslyn and it does not do any funny stuff like unmanaged memory access, so I suspect that this exception is a side-effect from a bug in AssemblyContextLoader..

Actual behavior

Application crashes and no way to recover from it.

Regression?

N/A

Known Workarounds

None

Configuration

.NET 7.0 on Windows 10 x64 build 19045

Other information

the code for the loader is taken from MSDN code:

 public class MyAssemblyLoader : AssemblyLoadContext//, IDisposable
{
private AssemblyDependencyResolver resolver;
public MyAssemblyLoader (string pluginPath) : base(pluginPath, true)
{
resolver = new AssemblyDependencyResolver(pluginPath);
}
protected override Assembly Load(AssemblyName assemblyName)
{
string assemblyPath = resolver.ResolveAssemblyToPath(assemblyName);
if (assemblyPath != null)
{
return LoadFromAssemblyPath(assemblyPath);
}
return null;
}
protected override IntPtr LoadUnmanagedDll(string unmanagedDllName)
{
string libraryPath = resolver.ResolveUnmanagedDllToPath(unmanagedDllName);
if (libraryPath != null)
{
return LoadUnmanagedDllFromPath(libraryPath);
}
return IntPtr.Zero;
}
}

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      , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all
       blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
      }
      } catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
      })();
      (function(){
      try {
      var __m = "github.com";
      var __re = new RegExp('^' + "github\\.com" + '
      
      Skip to content

      Calling AssemblyLoadContext.Unload multiple times causes fatal crash  #91087

      Description

      @maxima120

      Description

      Unfortunately I cant provide repro case (yet). But at least it is reproducible every time I try certain scenario in my app.

      I am getting this exception in WPF .NET 7 app. It happens when I try to unload a dll loaded in run-time.. The unload works if called correctly.

      But if it tries to call apploadingContext.Unload second time (there is a bug somewhere in my code) - the exception ExecutionEngineException is shown in VS if I debug and if I run it standalone I get this error in event log:

      Faulting application name: qqq.exe, version: 0.4.0.1, time stamp: 0x64b07659
      Faulting module name: coreclr.dll, version: 7.0.1023.36312, time stamp: 0x64b06d6c
      Exception code: 0xc0000005
      Fault offset: 0x0000000000133fa2
      Faulting process ID: 0xaea4
      Faulting application start time: 0x01d9d69df3fe6c1e
      Faulting application path: qqqq\bin\Debug\net7.0-windows\qqq.exe
      Faulting module path: C:\Program Files\dotnet\shared\Microsoft.NETCore.App\7.0.10\coreclr.dll
      Report ID: 9616639b-d2b2-4669-95da-65f25f23f4e7
      Faulting package full name: Faulting package-relative application ID: 

      Reproduction Steps

      N/A

      Expected behavior

      Since this exception marked as obsolete I think it should not be thrown. Perhaps new design should react on fatal conditions somehow differently.. Having said that I want to point that dll I am loading is few lines C# compiled in run-time with Roslyn and it does not do any funny stuff like unmanaged memory access, so I suspect that this exception is a side-effect from a bug in AssemblyContextLoader..

      Actual behavior

      Application crashes and no way to recover from it.

      Regression?

      N/A

      Known Workarounds

      None

      Configuration

      .NET 7.0 on Windows 10 x64 build 19045

      Other information

      the code for the loader is taken from MSDN code:

       public class MyAssemblyLoader : AssemblyLoadContext//, IDisposable
      {
      private AssemblyDependencyResolver resolver;
      public MyAssemblyLoader (string pluginPath) : base(pluginPath, true)
      {
      resolver = new AssemblyDependencyResolver(pluginPath);
      }
      protected override Assembly Load(AssemblyName assemblyName)
      {
      string assemblyPath = resolver.ResolveAssemblyToPath(assemblyName);
      if (assemblyPath != null)
      {
      return LoadFromAssemblyPath(assemblyPath);
      }
      return null;
      }
      protected override IntPtr LoadUnmanagedDll(string unmanagedDllName)
      {
      string libraryPath = resolver.ResolveUnmanagedDllToPath(unmanagedDllName);
      if (libraryPath != null)
      {
      return LoadUnmanagedDllFromPath(libraryPath);
      }
      return IntPtr.Zero;
      }
      }
      

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      No one assigned

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        No type

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          No milestone

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          None yet

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          No branches or pull requests

          Issue actions

          , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix"); } } catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
          Skip to content

          Calling AssemblyLoadContext.Unload multiple times causes fatal crash  #91087

          Description

          @maxima120

          Description

          Unfortunately I cant provide repro case (yet). But at least it is reproducible every time I try certain scenario in my app.

          I am getting this exception in WPF .NET 7 app. It happens when I try to unload a dll loaded in run-time.. The unload works if called correctly.

          But if it tries to call apploadingContext.Unload second time (there is a bug somewhere in my code) - the exception ExecutionEngineException is shown in VS if I debug and if I run it standalone I get this error in event log:

          Faulting application name: qqq.exe, version: 0.4.0.1, time stamp: 0x64b07659
          Faulting module name: coreclr.dll, version: 7.0.1023.36312, time stamp: 0x64b06d6c
          Exception code: 0xc0000005
          Fault offset: 0x0000000000133fa2
          Faulting process ID: 0xaea4
          Faulting application start time: 0x01d9d69df3fe6c1e
          Faulting application path: qqqq\bin\Debug\net7.0-windows\qqq.exe
          Faulting module path: C:\Program Files\dotnet\shared\Microsoft.NETCore.App\7.0.10\coreclr.dll
          Report ID: 9616639b-d2b2-4669-95da-65f25f23f4e7
          Faulting package full name: Faulting package-relative application ID: 

          Reproduction Steps

          N/A

          Expected behavior

          Since this exception marked as obsolete I think it should not be thrown. Perhaps new design should react on fatal conditions somehow differently.. Having said that I want to point that dll I am loading is few lines C# compiled in run-time with Roslyn and it does not do any funny stuff like unmanaged memory access, so I suspect that this exception is a side-effect from a bug in AssemblyContextLoader..

          Actual behavior

          Application crashes and no way to recover from it.

          Regression?

          N/A

          Known Workarounds

          None

          Configuration

          .NET 7.0 on Windows 10 x64 build 19045

          Other information

          the code for the loader is taken from MSDN code:

           public class MyAssemblyLoader : AssemblyLoadContext//, IDisposable
          {
          private AssemblyDependencyResolver resolver;
          public MyAssemblyLoader (string pluginPath) : base(pluginPath, true)
          {
          resolver = new AssemblyDependencyResolver(pluginPath);
          }
          protected override Assembly Load(AssemblyName assemblyName)
          {
          string assemblyPath = resolver.ResolveAssemblyToPath(assemblyName);
          if (assemblyPath != null)
          {
          return LoadFromAssemblyPath(assemblyPath);
          }
          return null;
          }
          protected override IntPtr LoadUnmanagedDll(string unmanagedDllName)
          {
          string libraryPath = resolver.ResolveUnmanagedDllToPath(unmanagedDllName);
          if (libraryPath != null)
          {
          return LoadUnmanagedDllFromPath(libraryPath);
          }
          return IntPtr.Zero;
          }
          }
          

          Metadata

          Metadata

          Assignees

          No one assigned

            Type

            No type

            Projects

            No projects

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              No milestone

              Relationships

              None yet

              Development

              No branches or pull requests

              Issue actions

              , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms"); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
              Skip to content

              Calling AssemblyLoadContext.Unload multiple times causes fatal crash  #91087

              Description

              @maxima120

              Description

              Unfortunately I cant provide repro case (yet). But at least it is reproducible every time I try certain scenario in my app.

              I am getting this exception in WPF .NET 7 app. It happens when I try to unload a dll loaded in run-time.. The unload works if called correctly.

              But if it tries to call apploadingContext.Unload second time (there is a bug somewhere in my code) - the exception ExecutionEngineException is shown in VS if I debug and if I run it standalone I get this error in event log:

              Faulting application name: qqq.exe, version: 0.4.0.1, time stamp: 0x64b07659
              Faulting module name: coreclr.dll, version: 7.0.1023.36312, time stamp: 0x64b06d6c
              Exception code: 0xc0000005
              Fault offset: 0x0000000000133fa2
              Faulting process ID: 0xaea4
              Faulting application start time: 0x01d9d69df3fe6c1e
              Faulting application path: qqqq\bin\Debug\net7.0-windows\qqq.exe
              Faulting module path: C:\Program Files\dotnet\shared\Microsoft.NETCore.App\7.0.10\coreclr.dll
              Report ID: 9616639b-d2b2-4669-95da-65f25f23f4e7
              Faulting package full name: Faulting package-relative application ID: 

              Reproduction Steps

              N/A

              Expected behavior

              Since this exception marked as obsolete I think it should not be thrown. Perhaps new design should react on fatal conditions somehow differently.. Having said that I want to point that dll I am loading is few lines C# compiled in run-time with Roslyn and it does not do any funny stuff like unmanaged memory access, so I suspect that this exception is a side-effect from a bug in AssemblyContextLoader..

              Actual behavior

              Application crashes and no way to recover from it.

              Regression?

              N/A

              Known Workarounds

              None

              Configuration

              .NET 7.0 on Windows 10 x64 build 19045

              Other information

              the code for the loader is taken from MSDN code:

               public class MyAssemblyLoader : AssemblyLoadContext//, IDisposable
              {
              private AssemblyDependencyResolver resolver;
              public MyAssemblyLoader (string pluginPath) : base(pluginPath, true)
              {
              resolver = new AssemblyDependencyResolver(pluginPath);
              }
              protected override Assembly Load(AssemblyName assemblyName)
              {
              string assemblyPath = resolver.ResolveAssemblyToPath(assemblyName);
              if (assemblyPath != null)
              {
              return LoadFromAssemblyPath(assemblyPath);
              }
              return null;
              }
              protected override IntPtr LoadUnmanagedDll(string unmanagedDllName)
              {
              string libraryPath = resolver.ResolveUnmanagedDllToPath(unmanagedDllName);
              if (libraryPath != null)
              {
              return LoadUnmanagedDllFromPath(libraryPath);
              }
              return IntPtr.Zero;
              }
              }
              

              Metadata

              Metadata

              Assignees

              No one assigned

                Type

                No type

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                No projects

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                  No milestone

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                  None yet

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                  No branches or pull requests

                  Issue actions

                  , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links"); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + '
                  Skip to content

                  Calling AssemblyLoadContext.Unload multiple times causes fatal crash  #91087

                  Description

                  @maxima120

                  Description

                  Unfortunately I cant provide repro case (yet). But at least it is reproducible every time I try certain scenario in my app.

                  I am getting this exception in WPF .NET 7 app. It happens when I try to unload a dll loaded in run-time.. The unload works if called correctly.

                  But if it tries to call apploadingContext.Unload second time (there is a bug somewhere in my code) - the exception ExecutionEngineException is shown in VS if I debug and if I run it standalone I get this error in event log:

                  Faulting application name: qqq.exe, version: 0.4.0.1, time stamp: 0x64b07659
                  Faulting module name: coreclr.dll, version: 7.0.1023.36312, time stamp: 0x64b06d6c
                  Exception code: 0xc0000005
                  Fault offset: 0x0000000000133fa2
                  Faulting process ID: 0xaea4
                  Faulting application start time: 0x01d9d69df3fe6c1e
                  Faulting application path: qqqq\bin\Debug\net7.0-windows\qqq.exe
                  Faulting module path: C:\Program Files\dotnet\shared\Microsoft.NETCore.App\7.0.10\coreclr.dll
                  Report ID: 9616639b-d2b2-4669-95da-65f25f23f4e7
                  Faulting package full name: Faulting package-relative application ID: 

                  Reproduction Steps

                  N/A

                  Expected behavior

                  Since this exception marked as obsolete I think it should not be thrown. Perhaps new design should react on fatal conditions somehow differently.. Having said that I want to point that dll I am loading is few lines C# compiled in run-time with Roslyn and it does not do any funny stuff like unmanaged memory access, so I suspect that this exception is a side-effect from a bug in AssemblyContextLoader..

                  Actual behavior

                  Application crashes and no way to recover from it.

                  Regression?

                  N/A

                  Known Workarounds

                  None

                  Configuration

                  .NET 7.0 on Windows 10 x64 build 19045

                  Other information

                  the code for the loader is taken from MSDN code:

                   public class MyAssemblyLoader : AssemblyLoadContext//, IDisposable
                  {
                  private AssemblyDependencyResolver resolver;
                  public MyAssemblyLoader (string pluginPath) : base(pluginPath, true)
                  {
                  resolver = new AssemblyDependencyResolver(pluginPath);
                  }
                  protected override Assembly Load(AssemblyName assemblyName)
                  {
                  string assemblyPath = resolver.ResolveAssemblyToPath(assemblyName);
                  if (assemblyPath != null)
                  {
                  return LoadFromAssemblyPath(assemblyPath);
                  }
                  return null;
                  }
                  protected override IntPtr LoadUnmanagedDll(string unmanagedDllName)
                  {
                  string libraryPath = resolver.ResolveUnmanagedDllToPath(unmanagedDllName);
                  if (libraryPath != null)
                  {
                  return LoadUnmanagedDllFromPath(libraryPath);
                  }
                  return IntPtr.Zero;
                  }
                  }
                  

                  Metadata

                  Metadata

                  Assignees

                  No one assigned

                    Type

                    No type

                    Projects

                    No projects

                      Milestone

                      No milestone

                      Relationships

                      None yet

                      Development

                      No branches or pull requests

                      Issue actions

                      , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default"); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
                      Skip to content

                      Calling AssemblyLoadContext.Unload multiple times causes fatal crash  #91087

                      Description

                      @maxima120

                      Description

                      Unfortunately I cant provide repro case (yet). But at least it is reproducible every time I try certain scenario in my app.

                      I am getting this exception in WPF .NET 7 app. It happens when I try to unload a dll loaded in run-time.. The unload works if called correctly.

                      But if it tries to call apploadingContext.Unload second time (there is a bug somewhere in my code) - the exception ExecutionEngineException is shown in VS if I debug and if I run it standalone I get this error in event log:

                      Faulting application name: qqq.exe, version: 0.4.0.1, time stamp: 0x64b07659
                      Faulting module name: coreclr.dll, version: 7.0.1023.36312, time stamp: 0x64b06d6c
                      Exception code: 0xc0000005
                      Fault offset: 0x0000000000133fa2
                      Faulting process ID: 0xaea4
                      Faulting application start time: 0x01d9d69df3fe6c1e
                      Faulting application path: qqqq\bin\Debug\net7.0-windows\qqq.exe
                      Faulting module path: C:\Program Files\dotnet\shared\Microsoft.NETCore.App\7.0.10\coreclr.dll
                      Report ID: 9616639b-d2b2-4669-95da-65f25f23f4e7
                      Faulting package full name: Faulting package-relative application ID: 

                      Reproduction Steps

                      N/A

                      Expected behavior

                      Since this exception marked as obsolete I think it should not be thrown. Perhaps new design should react on fatal conditions somehow differently.. Having said that I want to point that dll I am loading is few lines C# compiled in run-time with Roslyn and it does not do any funny stuff like unmanaged memory access, so I suspect that this exception is a side-effect from a bug in AssemblyContextLoader..

                      Actual behavior

                      Application crashes and no way to recover from it.

                      Regression?

                      N/A

                      Known Workarounds

                      None

                      Configuration

                      .NET 7.0 on Windows 10 x64 build 19045

                      Other information

                      the code for the loader is taken from MSDN code:

                       public class MyAssemblyLoader : AssemblyLoadContext//, IDisposable
                      {
                      private AssemblyDependencyResolver resolver;
                      public MyAssemblyLoader (string pluginPath) : base(pluginPath, true)
                      {
                      resolver = new AssemblyDependencyResolver(pluginPath);
                      }
                      protected override Assembly Load(AssemblyName assemblyName)
                      {
                      string assemblyPath = resolver.ResolveAssemblyToPath(assemblyName);
                      if (assemblyPath != null)
                      {
                      return LoadFromAssemblyPath(assemblyPath);
                      }
                      return null;
                      }
                      protected override IntPtr LoadUnmanagedDll(string unmanagedDllName)
                      {
                      string libraryPath = resolver.ResolveUnmanagedDllToPath(unmanagedDllName);
                      if (libraryPath != null)
                      {
                      return LoadUnmanagedDllFromPath(libraryPath);
                      }
                      return IntPtr.Zero;
                      }
                      }
                      

                      Metadata

                      Metadata

                      Assignees

                      No one assigned

                        Type

                        No type

                        Projects

                        No projects

                          Milestone

                          No milestone

                          Relationships

                          None yet

                          Development

                          No branches or pull requests

                          Issue actions

                          , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers"); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
                          Skip to content

                          Calling AssemblyLoadContext.Unload multiple times causes fatal crash  #91087

                          Description

                          @maxima120

                          Description

                          Unfortunately I cant provide repro case (yet). But at least it is reproducible every time I try certain scenario in my app.

                          I am getting this exception in WPF .NET 7 app. It happens when I try to unload a dll loaded in run-time.. The unload works if called correctly.

                          But if it tries to call apploadingContext.Unload second time (there is a bug somewhere in my code) - the exception ExecutionEngineException is shown in VS if I debug and if I run it standalone I get this error in event log:

                          Faulting application name: qqq.exe, version: 0.4.0.1, time stamp: 0x64b07659
                          Faulting module name: coreclr.dll, version: 7.0.1023.36312, time stamp: 0x64b06d6c
                          Exception code: 0xc0000005
                          Fault offset: 0x0000000000133fa2
                          Faulting process ID: 0xaea4
                          Faulting application start time: 0x01d9d69df3fe6c1e
                          Faulting application path: qqqq\bin\Debug\net7.0-windows\qqq.exe
                          Faulting module path: C:\Program Files\dotnet\shared\Microsoft.NETCore.App\7.0.10\coreclr.dll
                          Report ID: 9616639b-d2b2-4669-95da-65f25f23f4e7
                          Faulting package full name: Faulting package-relative application ID: 

                          Reproduction Steps

                          N/A

                          Expected behavior

                          Since this exception marked as obsolete I think it should not be thrown. Perhaps new design should react on fatal conditions somehow differently.. Having said that I want to point that dll I am loading is few lines C# compiled in run-time with Roslyn and it does not do any funny stuff like unmanaged memory access, so I suspect that this exception is a side-effect from a bug in AssemblyContextLoader..

                          Actual behavior

                          Application crashes and no way to recover from it.

                          Regression?

                          N/A

                          Known Workarounds

                          None

                          Configuration

                          .NET 7.0 on Windows 10 x64 build 19045

                          Other information

                          the code for the loader is taken from MSDN code:

                           public class MyAssemblyLoader : AssemblyLoadContext//, IDisposable
                          {
                          private AssemblyDependencyResolver resolver;
                          public MyAssemblyLoader (string pluginPath) : base(pluginPath, true)
                          {
                          resolver = new AssemblyDependencyResolver(pluginPath);
                          }
                          protected override Assembly Load(AssemblyName assemblyName)
                          {
                          string assemblyPath = resolver.ResolveAssemblyToPath(assemblyName);
                          if (assemblyPath != null)
                          {
                          return LoadFromAssemblyPath(assemblyPath);
                          }
                          return null;
                          }
                          protected override IntPtr LoadUnmanagedDll(string unmanagedDllName)
                          {
                          string libraryPath = resolver.ResolveUnmanagedDllToPath(unmanagedDllName);
                          if (libraryPath != null)
                          {
                          return LoadUnmanagedDllFromPath(libraryPath);
                          }
                          return IntPtr.Zero;
                          }
                          }
                          

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                              No milestone

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                              None yet

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                              No branches or pull requests

                              Issue actions

                              , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode"); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })();
                              Skip to content

                              Calling AssemblyLoadContext.Unload multiple times causes fatal crash  #91087

                              Description

                              @maxima120

                              Description

                              Unfortunately I cant provide repro case (yet). But at least it is reproducible every time I try certain scenario in my app.

                              I am getting this exception in WPF .NET 7 app. It happens when I try to unload a dll loaded in run-time.. The unload works if called correctly.

                              But if it tries to call apploadingContext.Unload second time (there is a bug somewhere in my code) - the exception ExecutionEngineException is shown in VS if I debug and if I run it standalone I get this error in event log:

                              Faulting application name: qqq.exe, version: 0.4.0.1, time stamp: 0x64b07659
                              Faulting module name: coreclr.dll, version: 7.0.1023.36312, time stamp: 0x64b06d6c
                              Exception code: 0xc0000005
                              Fault offset: 0x0000000000133fa2
                              Faulting process ID: 0xaea4
                              Faulting application start time: 0x01d9d69df3fe6c1e
                              Faulting application path: qqqq\bin\Debug\net7.0-windows\qqq.exe
                              Faulting module path: C:\Program Files\dotnet\shared\Microsoft.NETCore.App\7.0.10\coreclr.dll
                              Report ID: 9616639b-d2b2-4669-95da-65f25f23f4e7
                              Faulting package full name: Faulting package-relative application ID: 

                              Reproduction Steps

                              N/A

                              Expected behavior

                              Since this exception marked as obsolete I think it should not be thrown. Perhaps new design should react on fatal conditions somehow differently.. Having said that I want to point that dll I am loading is few lines C# compiled in run-time with Roslyn and it does not do any funny stuff like unmanaged memory access, so I suspect that this exception is a side-effect from a bug in AssemblyContextLoader..

                              Actual behavior

                              Application crashes and no way to recover from it.

                              Regression?

                              N/A

                              Known Workarounds

                              None

                              Configuration

                              .NET 7.0 on Windows 10 x64 build 19045

                              Other information

                              the code for the loader is taken from MSDN code:

                               public class MyAssemblyLoader : AssemblyLoadContext//, IDisposable
                              {
                              private AssemblyDependencyResolver resolver;
                              public MyAssemblyLoader (string pluginPath) : base(pluginPath, true)
                              {
                              resolver = new AssemblyDependencyResolver(pluginPath);
                              }
                              protected override Assembly Load(AssemblyName assemblyName)
                              {
                              string assemblyPath = resolver.ResolveAssemblyToPath(assemblyName);
                              if (assemblyPath != null)
                              {
                              return LoadFromAssemblyPath(assemblyPath);
                              }
                              return null;
                              }
                              protected override IntPtr LoadUnmanagedDll(string unmanagedDllName)
                              {
                              string libraryPath = resolver.ResolveUnmanagedDllToPath(unmanagedDllName);
                              if (libraryPath != null)
                              {
                              return LoadUnmanagedDllFromPath(libraryPath);
                              }
                              return IntPtr.Zero;
                              }
                              }
                              

                              Metadata

                              Metadata

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                              No one assigned

                                Type

                                No type

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                                No projects

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                                  No branches or pull requests

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