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jaredpar / net472-unittest-migration-analysis.md
Created April 29, 2026 21:40

net472-only UnitTests Projects — .NET Core/Linux Migration Candidates

Analyzed all 16 net472-only .UnitTests projects in dotnet/roslyn. Excluded 9 with Visual Studio/WPF hard dependencies. 7 candidates remain.

Low Effort (easiest wins)

Project Notes
CodeStyle/CSharp/Tests Pure analyzer testing, no VS/WPF deps. Straightforward.
Features/ExternalAccess/OmniSharpTest Minimal deps — OmniSharp.CSharp targets netstandard2.0. Very clean.
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jaredpar / plan.md
Created April 21, 2026 04:32
BlobBuilder Allocation Strategy Plan — System.Reflection.Metadata pooling for Roslyn VBCSCompiler

BlobBuilder Allocation Strategy Plan

Problem Statement

Roslyn's VBCSCompiler process suffers from significant byte[] allocations driven by System.Reflection.Metadata APIs, primarily through BlobBuilder. The goal is to enable a pooling strategy where Roslyn pre-allocates ~4MB of byte[] and PE file writing completes with zero (or near-zero) additional allocations.

BlobBuilder Architecture Deep Dive

What BlobBuilder Is

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jaredpar / intentional-no-action-comments.md
Created April 3, 2026 23:29
Intentional no-action comments in Roslyn codebase

Intentional No-Action Comments in Roslyn

Comments across C# and VB files where developers explicitly indicated no action is taken.

C# Files

Compilers

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jaredpar / build-server-shutdown.md
Created January 14, 2025 01:46
Suggestion for how to better implement build-server shutdown

Shutting down our build servers

Motivation

The .NET build contains a number of long lived server processes: msbuild nodes, razor and roslyn. A requirement of the .NET SDK is for customers to be able to reliably shut down all servers created during any build. This is important for shutting down a build operation and ensuring that no files remain locked on disk.

This challenging because there is no easy answer to discovering which processes are build servers:

  • These are primarily .NET SDK process which means they all share the same process name: dotnet
  • These processes do not have a strict parent / child relationship with build commands. Several, like roslyn, live past the msbuild nodes that created them.
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jaredpar / line-reader.cs
Created January 9, 2025 01:25
Read a file line by line without allocating too muuch
public ref struct LineEnumerator(string filePath) : IDisposable
{
private static SearchValues<char> NewLines = SearchValues.Create('\r', '\n');
private StreamReader _reader = new StreamReader(filePath);
private char[] _array = ArrayPool<char>.Shared.Rent(1024);
// This represents the data read from the file that hasn't been processed yet. This will
// be a subset of _array
private Span<char> _buffer = Span<char>.Empty;
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jaredpar / notes.md
Created July 12, 2024 20:47
notes
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jaredpar / gist:a4161bc9fee08953a173d5219c08ee6e
Created November 15, 2023 19:18
C:\Users\jaredpar\code\PublicBugs\CscAnal>REM passing Newtonsoft.Json.dll 13.0.0.0 works fine and results in the expected:
C:\Users\jaredpar\code\PublicBugs\CscAnal>REM arning CS8785: Generator 'Generator' failed to generate source. It will not contribute to the output and compilation errors may occur as a result. Exception was of type 'ArgumentNullException' with message 'Value cannot be null.
C:\Users\jaredpar\code\PublicBugs\CscAnal>REM Parameter name: source'
C:\Users\jaredpar\code\PublicBugs\CscAnal>REM
C:\Users\jaredpar\code\PublicBugs\CscAnal>REM Loaded modules:
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jaredpar / read-nullable-enable.cs
Created August 30, 2023 17:19
using System.Reflection.Metadata;
using System.Reflection.PortableExecutable;
Console.WriteLine(IsNullableEnabledAtBuild(@"C:\Users\jaredpar\temp\console\bin\Debug\net7.0\console.dll", out var reason));
Console.WriteLine(reason);
static bool IsNullableEnabledAtBuild(string assemblyFilePath, out string? reason)
{
MetadataReaderProvider? pdbReaderProvider = null;
try
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jaredpar / repro.ps1
Created August 24, 2023 21:51
& 'C:\Program Files\Microsoft Visual Studio\2022\Enterprise\Common7\IDE\CommonExtensions\Microsoft\NuGet\NuGet.Build.Tasks.Console.exe' 'Recursive=True;CleanupAssetsForUnsupportedProjects=True;DisableParallel=False;Force=False;ForceEvaluate=False;HideWarningsAndErrors=False;IgnoreFailedSources=False;Interactive=False;NoCache=False;RestorePackagesConfig=False" "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\MSBuild\Current\Bin\MSBuild.exe" "C:\Users\jaredpar\code\roslyn\Roslyn.sln" "ContinuousIntegrationBuild=False;TreatWarningsAsErrors=False;Configuration=Debug;RepoRoot=C:\Users\jaredpar\code\roslyn\;Rebuild=False;OfficialBuildId=;RunAnalyzersDuringBuild=False;BootstrapBuildPath=;EnableNgenOptimization=False;IbcOptimizationDataDir=C:\Users\jaredpar\code\roslyn\.o%5c;RestoreUseStaticGraphEvaluation=True;VisualStudioIbcDrop=;VisualStudioDropAccessToken=;IsNpmPackable=True;DeployExtension=false;VersionsPropsPath=C:\Users\jaredpar\code\roslyn\eng\Versions.props;VCTargetsPath=C:\Program Files\Microsoft V
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jaredpar / secure-boot.txt
Created April 14, 2023 03:25
This is gonna be complicated.
1. I assume you are using an hp desktop? I think thats what the company gets ppl nowadays
2. As sam says, you must disable bitlocker before mucking around
with that out of the way you need to ensure you check all these boxes
1. you have a TPU installed on your machine and its enabled:
- Turn on the computer and press the f10 key to start to the BIOS setup menu.
- On the Security tab, check whether your TPM Device status is Hidden.