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NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005) #79486

Closed
#80302
Closed
NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005)#79486
#80302
Assignees
mrsharm
Labels
area-GC-coreclr
Milestone
8.0.0

Description

@nilekirk
nilekirk
opened on Dec 10, 2022

Description

Calling GC.Collect() when having sufficiently large objects in LOH and using the Server Garbage Collection causes Access Violation exception (cx0000005) being thrown from coreclr.dll

CoreCLR Version: 7.0.22.51805
.NET Version: 7.0.0
Description: The process was terminated due to an unhandled exception.
Exception Info: exception code c0000005

We have seen this on Windows 10 Enterprise and on Windows Server 2016

Reproduction Steps

Code

open System
[<Struct>]
type T = {
A: DateTime
B: int
C: float
D: byte }
let data: T array = Array.zeroCreate 2_000_000_000
GC.Collect()
printfn "All OK"

Project file

<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ServerGarbageCollection>true</ServerGarbageCollection>
</PropertyGroup>
<ItemGroup>
<Compile Include="Program.fs" />
</ItemGroup>
</Project>

Run this with dotnet run -c release

Changes that leads to program running OK

  • Allocating with size 1_000_000_000
  • Changing the order of B and C in the struct

Expected behavior

The program writes All OK to the console.

Actual behavior

The program crashes and we see in the Event log that The process was terminated due to an unhandled exception with exception code c0000005

Regression?

We never saw this on NET 6, but it appeared immediately efter we upgraded to NET 7.

Known Workarounds

No response

Configuration

.NET version

CoreCLR Version: 7.0.22.51805
.NET Version: 7.0.0

OS

Edition Windows 10 Enterprise
Version 21H2
Installed on ‎03/‎10/‎2020
OS build 19044.2251
Experience Windows Feature Experience Pack 120.2212.4180.0

Architecture

x64

Other information

No response

Metadata

Metadata

Assignees

Labels

area-GC-coreclr

Type

No type

Projects

No projects

    Milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions

    , 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
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setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
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(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
NET 7: Calling `GC.Collect()` causes Access Violation exception (cx0000005) · Issue #79486 · dotnet/runtime · GitHub
    Skip to content
    NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005) #79486
    Closed
    #80302
    Closed
    NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005)#79486
    #80302
    Assignees
    mrsharm
    Labels
    area-GC-coreclr
    Milestone
    8.0.0
    Description
    @nilekirk
    nilekirk
    opened on Dec 10, 2022
    Description
    Calling GC.Collect() when having sufficiently large objects in LOH and using the Server Garbage Collection causes Access Violation exception (cx0000005) being thrown from coreclr.dll
    CoreCLR Version: 7.0.22.51805
.NET Version: 7.0.0
Description: The process was terminated due to an unhandled exception.
Exception Info: exception code c0000005

    We have seen this on Windows 10 Enterprise and on Windows Server 2016
    Reproduction Steps
    Code
    open System
[<Struct>]
type T = {
A: DateTime
B: int
C: float
D: byte }
let data: T array = Array.zeroCreate 2_000_000_000
GC.Collect()
printfn "All OK"

    Project file
    <Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ServerGarbageCollection>true</ServerGarbageCollection>
</PropertyGroup>
<ItemGroup>
<Compile Include="Program.fs" />
</ItemGroup>
</Project>

    Run this with dotnet run -c release
    Changes that leads to program running OK
    • Allocating with size 1_000_000_000
    • Changing the order of B and C in the struct
    Expected behavior
    The program writes All OK to the console.
    Actual behavior
    The program crashes and we see in the Event log that The process was terminated due to an unhandled exception with exception code c0000005
    Regression?
    We never saw this on NET 6, but it appeared immediately efter we upgraded to NET 7.
    Known Workarounds
    No response
    Configuration
    .NET version
    CoreCLR Version: 7.0.22.51805
    
.NET Version: 7.0.0
    OS
    Edition	Windows 10 Enterprise
    
Version	21H2
    
Installed on	‎03/‎10/‎2020
    
OS build	19044.2251
    
Experience	Windows Feature Experience Pack 120.2212.4180.0
    Architecture
    x64
    Other information
    No response
    Metadata
    Metadata
    Assignees
    Labels
    area-GC-coreclr
    Type
    No type
    Projects
    No projects
      Milestone
      Relationships
      None yet
      Development
      No branches or pull requests
      Issue actions
      
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
.markdown-body img { background: #0d1117; }
.markdown-body blockquote { border-left-color: #8b949e; }
.markdown-body hr { border-color: #30363d; }
';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
NET 7: Calling `GC.Collect()` causes Access Violation exception (cx0000005) · Issue #79486 · dotnet/runtime · GitHub
      Skip to content
      NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005) #79486
      Closed
      #80302
      Closed
      NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005)#79486
      #80302
      Assignees
      mrsharm
      Labels
      area-GC-coreclr
      Milestone
      8.0.0
      Description
      @nilekirk
      nilekirk
      opened on Dec 10, 2022
      Description
      Calling GC.Collect() when having sufficiently large objects in LOH and using the Server Garbage Collection causes Access Violation exception (cx0000005) being thrown from coreclr.dll
      CoreCLR Version: 7.0.22.51805
.NET Version: 7.0.0
Description: The process was terminated due to an unhandled exception.
Exception Info: exception code c0000005

      We have seen this on Windows 10 Enterprise and on Windows Server 2016
      Reproduction Steps
      Code
      open System
[<Struct>]
type T = {
A: DateTime
B: int
C: float
D: byte }
let data: T array = Array.zeroCreate 2_000_000_000
GC.Collect()
printfn "All OK"

      Project file
      <Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ServerGarbageCollection>true</ServerGarbageCollection>
</PropertyGroup>
<ItemGroup>
<Compile Include="Program.fs" />
</ItemGroup>
</Project>

      Run this with dotnet run -c release
      Changes that leads to program running OK
      • Allocating with size 1_000_000_000
      • Changing the order of B and C in the struct
      Expected behavior
      The program writes All OK to the console.
      Actual behavior
      The program crashes and we see in the Event log that The process was terminated due to an unhandled exception with exception code c0000005
      Regression?
      We never saw this on NET 6, but it appeared immediately efter we upgraded to NET 7.
      Known Workarounds
      No response
      Configuration
      .NET version
      CoreCLR Version: 7.0.22.51805
      
.NET Version: 7.0.0
      OS
      Edition	Windows 10 Enterprise
      
Version	21H2
      
Installed on	‎03/‎10/‎2020
      
OS build	19044.2251
      
Experience	Windows Feature Experience Pack 120.2212.4180.0
      Architecture
      x64
      Other information
      No response
      Metadata
      Metadata
      Assignees
      Labels
      area-GC-coreclr
      Type
      No type
      Projects
      No projects
        Milestone
        Relationships
        None yet
        Development
        No branches or pull requests
        Issue actions
        
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
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} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
NET 7: Calling `GC.Collect()` causes Access Violation exception (cx0000005) · Issue #79486 · dotnet/runtime · GitHub
        Skip to content
        NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005) #79486
        Closed
        #80302
        Closed
        NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005)#79486
        #80302
        Assignees
        mrsharm
        Labels
        area-GC-coreclr
        Milestone
        8.0.0
        Description
        @nilekirk
        nilekirk
        opened on Dec 10, 2022
        Description
        Calling GC.Collect() when having sufficiently large objects in LOH and using the Server Garbage Collection causes Access Violation exception (cx0000005) being thrown from coreclr.dll
        CoreCLR Version: 7.0.22.51805
.NET Version: 7.0.0
Description: The process was terminated due to an unhandled exception.
Exception Info: exception code c0000005

        We have seen this on Windows 10 Enterprise and on Windows Server 2016
        Reproduction Steps
        Code
        open System
[<Struct>]
type T = {
A: DateTime
B: int
C: float
D: byte }
let data: T array = Array.zeroCreate 2_000_000_000
GC.Collect()
printfn "All OK"

        Project file
        <Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ServerGarbageCollection>true</ServerGarbageCollection>
</PropertyGroup>
<ItemGroup>
<Compile Include="Program.fs" />
</ItemGroup>
</Project>

        Run this with dotnet run -c release
        Changes that leads to program running OK
        • Allocating with size 1_000_000_000
        • Changing the order of B and C in the struct
        Expected behavior
        The program writes All OK to the console.
        Actual behavior
        The program crashes and we see in the Event log that The process was terminated due to an unhandled exception with exception code c0000005
        Regression?
        We never saw this on NET 6, but it appeared immediately efter we upgraded to NET 7.
        Known Workarounds
        No response
        Configuration
        .NET version
        CoreCLR Version: 7.0.22.51805
        
.NET Version: 7.0.0
        OS
        Edition	Windows 10 Enterprise
        
Version	21H2
        
Installed on	‎03/‎10/‎2020
        
OS build	19044.2251
        
Experience	Windows Feature Experience Pack 120.2212.4180.0
        Architecture
        x64
        Other information
        No response
        Metadata
        Metadata
        Assignees
        Labels
        area-GC-coreclr
        Type
        No type
        Projects
        No projects
          Milestone
          Relationships
          None yet
          Development
          No branches or pull requests
          Issue actions
          
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
NET 7: Calling `GC.Collect()` causes Access Violation exception (cx0000005) · Issue #79486 · dotnet/runtime · GitHub
          Skip to content
          NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005) #79486
          Closed
          #80302
          Closed
          NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005)#79486
          #80302
          Assignees
          mrsharm
          Labels
          area-GC-coreclr
          Milestone
          8.0.0
          Description
          @nilekirk
          nilekirk
          opened on Dec 10, 2022
          Description
          Calling GC.Collect() when having sufficiently large objects in LOH and using the Server Garbage Collection causes Access Violation exception (cx0000005) being thrown from coreclr.dll
          CoreCLR Version: 7.0.22.51805
.NET Version: 7.0.0
Description: The process was terminated due to an unhandled exception.
Exception Info: exception code c0000005

          We have seen this on Windows 10 Enterprise and on Windows Server 2016
          Reproduction Steps
          Code
          open System
[<Struct>]
type T = {
A: DateTime
B: int
C: float
D: byte }
let data: T array = Array.zeroCreate 2_000_000_000
GC.Collect()
printfn "All OK"

          Project file
          <Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ServerGarbageCollection>true</ServerGarbageCollection>
</PropertyGroup>
<ItemGroup>
<Compile Include="Program.fs" />
</ItemGroup>
</Project>

          Run this with dotnet run -c release
          Changes that leads to program running OK
          • Allocating with size 1_000_000_000
          • Changing the order of B and C in the struct
          Expected behavior
          The program writes All OK to the console.
          Actual behavior
          The program crashes and we see in the Event log that The process was terminated due to an unhandled exception with exception code c0000005
          Regression?
          We never saw this on NET 6, but it appeared immediately efter we upgraded to NET 7.
          Known Workarounds
          No response
          Configuration
          .NET version
          CoreCLR Version: 7.0.22.51805
          
.NET Version: 7.0.0
          OS
          Edition	Windows 10 Enterprise
          
Version	21H2
          
Installed on	‎03/‎10/‎2020
          
OS build	19044.2251
          
Experience	Windows Feature Experience Pack 120.2212.4180.0
          Architecture
          x64
          Other information
          No response
          Metadata
          Metadata
          Assignees
          Labels
          area-GC-coreclr
          Type
          No type
          Projects
          No projects
            Milestone
            Relationships
            None yet
            Development
            No branches or pull requests
            Issue actions
            
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
NET 7: Calling `GC.Collect()` causes Access Violation exception (cx0000005) · Issue #79486 · dotnet/runtime · GitHub
            Skip to content
            NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005) #79486
            Closed
            #80302
            Closed
            NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005)#79486
            #80302
            Assignees
            mrsharm
            Labels
            area-GC-coreclr
            Milestone
            8.0.0
            Description
            @nilekirk
            nilekirk
            opened on Dec 10, 2022
            Description
            Calling GC.Collect() when having sufficiently large objects in LOH and using the Server Garbage Collection causes Access Violation exception (cx0000005) being thrown from coreclr.dll
            CoreCLR Version: 7.0.22.51805
.NET Version: 7.0.0
Description: The process was terminated due to an unhandled exception.
Exception Info: exception code c0000005

            We have seen this on Windows 10 Enterprise and on Windows Server 2016
            Reproduction Steps
            Code
            open System
[<Struct>]
type T = {
A: DateTime
B: int
C: float
D: byte }
let data: T array = Array.zeroCreate 2_000_000_000
GC.Collect()
printfn "All OK"

            Project file
            <Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ServerGarbageCollection>true</ServerGarbageCollection>
</PropertyGroup>
<ItemGroup>
<Compile Include="Program.fs" />
</ItemGroup>
</Project>

            Run this with dotnet run -c release
            Changes that leads to program running OK
            • Allocating with size 1_000_000_000
            • Changing the order of B and C in the struct
            Expected behavior
            The program writes All OK to the console.
            Actual behavior
            The program crashes and we see in the Event log that The process was terminated due to an unhandled exception with exception code c0000005
            Regression?
            We never saw this on NET 6, but it appeared immediately efter we upgraded to NET 7.
            Known Workarounds
            No response
            Configuration
            .NET version
            CoreCLR Version: 7.0.22.51805
            
.NET Version: 7.0.0
            OS
            Edition	Windows 10 Enterprise
            
Version	21H2
            
Installed on	‎03/‎10/‎2020
            
OS build	19044.2251
            
Experience	Windows Feature Experience Pack 120.2212.4180.0
            Architecture
            x64
            Other information
            No response
            Metadata
            Metadata
            Assignees
            Labels
            area-GC-coreclr
            Type
            No type
            Projects
            No projects
              Milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
NET 7: Calling `GC.Collect()` causes Access Violation exception (cx0000005) · Issue #79486 · dotnet/runtime · GitHub
              Skip to content
              NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005) #79486
              Closed
              #80302
              Closed
              NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005)#79486
              #80302
              Assignees
              mrsharm
              Labels
              area-GC-coreclr
              Milestone
              8.0.0
              Description
              @nilekirk
              nilekirk
              opened on Dec 10, 2022
              Description
              Calling GC.Collect() when having sufficiently large objects in LOH and using the Server Garbage Collection causes Access Violation exception (cx0000005) being thrown from coreclr.dll
              CoreCLR Version: 7.0.22.51805
.NET Version: 7.0.0
Description: The process was terminated due to an unhandled exception.
Exception Info: exception code c0000005

              We have seen this on Windows 10 Enterprise and on Windows Server 2016
              Reproduction Steps
              Code
              open System
[<Struct>]
type T = {
A: DateTime
B: int
C: float
D: byte }
let data: T array = Array.zeroCreate 2_000_000_000
GC.Collect()
printfn "All OK"

              Project file
              <Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ServerGarbageCollection>true</ServerGarbageCollection>
</PropertyGroup>
<ItemGroup>
<Compile Include="Program.fs" />
</ItemGroup>
</Project>

              Run this with dotnet run -c release
              Changes that leads to program running OK
              • Allocating with size 1_000_000_000
              • Changing the order of B and C in the struct
              Expected behavior
              The program writes All OK to the console.
              Actual behavior
              The program crashes and we see in the Event log that The process was terminated due to an unhandled exception with exception code c0000005
              Regression?
              We never saw this on NET 6, but it appeared immediately efter we upgraded to NET 7.
              Known Workarounds
              No response
              Configuration
              .NET version
              CoreCLR Version: 7.0.22.51805
              
.NET Version: 7.0.0
              OS
              Edition	Windows 10 Enterprise
              
Version	21H2
              
Installed on	‎03/‎10/‎2020
              
OS build	19044.2251
              
Experience	Windows Feature Experience Pack 120.2212.4180.0
              Architecture
              x64
              Other information
              No response
              Metadata
              Metadata
              Assignees
              Labels
              area-GC-coreclr
              Type
              No type
              Projects
              No projects
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                None yet
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                No branches or pull requests
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
NET 7: Calling `GC.Collect()` causes Access Violation exception (cx0000005) · Issue #79486 · dotnet/runtime · GitHub
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                NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005) #79486
                Closed
                #80302
                Closed
                NET 7: Calling GC.Collect() causes Access Violation exception (cx0000005)#79486
                #80302
                Assignees
                mrsharm
                Labels
                area-GC-coreclr
                Milestone
                8.0.0
                Description
                @nilekirk
                nilekirk
                opened on Dec 10, 2022
                Description
                Calling GC.Collect() when having sufficiently large objects in LOH and using the Server Garbage Collection causes Access Violation exception (cx0000005) being thrown from coreclr.dll
                CoreCLR Version: 7.0.22.51805
.NET Version: 7.0.0
Description: The process was terminated due to an unhandled exception.
Exception Info: exception code c0000005

                We have seen this on Windows 10 Enterprise and on Windows Server 2016
                Reproduction Steps
                Code
                open System
[<Struct>]
type T = {
A: DateTime
B: int
C: float
D: byte }
let data: T array = Array.zeroCreate 2_000_000_000
GC.Collect()
printfn "All OK"

                Project file
                <Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ServerGarbageCollection>true</ServerGarbageCollection>
</PropertyGroup>
<ItemGroup>
<Compile Include="Program.fs" />
</ItemGroup>
</Project>

                Run this with dotnet run -c release
                Changes that leads to program running OK
                • Allocating with size 1_000_000_000
                • Changing the order of B and C in the struct
                Expected behavior
                The program writes All OK to the console.
                Actual behavior
                The program crashes and we see in the Event log that The process was terminated due to an unhandled exception with exception code c0000005
                Regression?
                We never saw this on NET 6, but it appeared immediately efter we upgraded to NET 7.
                Known Workarounds
                No response
                Configuration
                .NET version
                CoreCLR Version: 7.0.22.51805
                
.NET Version: 7.0.0
                OS
                Edition	Windows 10 Enterprise
                
Version	21H2
                
Installed on	‎03/‎10/‎2020
                
OS build	19044.2251
                
Experience	Windows Feature Experience Pack 120.2212.4180.0
                Architecture
                x64
                Other information
                No response
                Metadata
                Metadata
                Assignees
                Labels
                area-GC-coreclr
                Type
                No type
                Projects
                No projects
                  Milestone
                  Relationships
                  None yet
                  Development
                  No branches or pull requests
                  Issue actions