Remove reflection from FrameworkDescription

src/libraries/System.Private.CoreLib/gen/DotnetProductVersionInfoGenerator.cs

@@ -0,0 +1,42 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Collections.Immutable;
+using System.IO;
+using Microsoft.CodeAnalysis;
+
+namespace Generators
+{
+    [Generator]
+    public partial class DotnetProductVersionInfoGenerator : IIncrementalGenerator
+    {
+        public void Initialize(IncrementalGeneratorInitializationContext context)
+        {
+            // we only care about filename which is of the form "$(Version).versionstring", no need to actually read the file.
+            IncrementalValuesProvider<AdditionalText> textFiles = context.AdditionalTextsProvider.Where(static file => file.Path.EndsWith(".versionstring"));
+            IncrementalValueProvider<(Compilation Left, ImmutableArray<AdditionalText> Right)> compilationAndFiles =
+                context.CompilationProvider.Combine(textFiles.Collect());
+
+            context.RegisterSourceOutput(compilationAndFiles, (spc, content) =>
+            {
+                // strip semver metadata (git hash) followed by + sign
+                string? productVersion = Path.GetFileNameWithoutExtension(content.Right[0].Path.Split('+')?[0]);
+
+                if (productVersion is null)
+                    throw new InvalidOperationException($"Unable to get product version at build time.");
+
+                spc.AddSource("Environment.DotnetProductVersionInfo.g.cs", $@"
+// <auto-generated/>
+
+namespace System;
+
+public static partial class Environment
+{{
+    internal const string ProductVersionWithLabel = ""{productVersion}"";
+    private const string ProductVersionWithoutLabel = ""{productVersion.Split('-')?[0]}"";
+}}");
+            });
+        }
+    }
+}

src/libraries/System.Private.CoreLib/gen/System.Private.CoreLib.Generators.csproj

@@ -5,6 +5,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <Compile Include="DotnetProductVersionInfoGenerator.cs" />
     <Compile Include="EventSourceGenerator.cs" />
     <Compile Include="EventSourceGenerator.Emitter.cs" />
     <Compile Include="EventSourceGenerator.Parser.cs" />
@@ -20,4 +21,5 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp" PrivateAssets="all" Version="$(MicrosoftCodeAnalysisVersion_LatestVS)" />
   </ItemGroup>
+
 </Project>

src/libraries/System.Private.CoreLib/src/System.Private.CoreLib.Shared.projitems

@@ -2783,4 +2783,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Numerics\IUnaryPlusOperators.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Numerics\IUnsignedNumber.cs" />
   </ItemGroup>
+  <ItemGroup>
+    <AdditionalFiles Include="$(Version).versionstring" />
+  </ItemGroup>
 </Project>

src/libraries/System.Private.CoreLib/src/System/Environment.cs

@@ -201,23 +201,7 @@ public static OperatingSystem OSVersion
             }
         }
 
-        public static Version Version
-        {
-            get
-            {
-                string? versionString = typeof(object).Assembly.GetCustomAttribute<AssemblyInformationalVersionAttribute>()?.InformationalVersion;
-
-                ReadOnlySpan<char> versionSpan = versionString.AsSpan();
-
-                // Strip optional suffixes
-                int separatorIndex = versionSpan.IndexOfAny('-', '+', ' ');
-                if (separatorIndex >= 0)
-                    versionSpan = versionSpan.Slice(0, separatorIndex);
-
-                // Return zeros rather then failing if the version string fails to parse
-                return Version.TryParse(versionSpan, out Version? version) ? version : new Version();
-            }
-        }
+        public static Version Version => Version.Parse(ProductVersionWithoutLabel);
 
         public static string StackTrace
         {

src/libraries/System.Private.CoreLib/src/System/Runtime/InteropServices/RuntimeInformation.cs

@@ -1,37 +1,16 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-using System.Reflection;
-
 namespace System.Runtime.InteropServices
 {
     public static partial class RuntimeInformation
     {
-        private const string FrameworkName = ".NET";
-        private static string? s_frameworkDescription;
         private static string? s_runtimeIdentifier;
 
-        public static string FrameworkDescription
-        {
-            get
-            {
-                if (s_frameworkDescription == null)
-                {
-                    ReadOnlySpan<char> versionString = typeof(object).Assembly.GetCustomAttribute<AssemblyInformationalVersionAttribute>()?.InformationalVersion;
-
-                    // Strip the git hash if there is one
-                    int plusIndex = versionString.IndexOf('+');
-                    if (plusIndex >= 0)
-                    {
-                        versionString = versionString.Slice(0, plusIndex);
-                    }
-
-                    s_frameworkDescription = !versionString.Trim().IsEmpty ? $"{FrameworkName} {versionString}" : FrameworkName;
-                }
-
-                return s_frameworkDescription;
-            }
-        }
+        /// <summary>
+        /// Gets the name of the .NET installation on which an app is running.
+        /// </summary>
+        public static string FrameworkDescription { get; } = ".NET " + Environment.ProductVersionWithLabel;
 
         /// <summary>
         /// Returns an opaque string that identifies the platform on which an app is running.

src/libraries/System.Runtime/tests/System.Runtime.InteropServices.RuntimeInformation.Tests/System.Runtime.InteropServices.RuntimeInformation.Tests.csproj

@@ -4,9 +4,6 @@
     <IncludeRemoteExecutor>true</IncludeRemoteExecutor>
     <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-unix;$(NetCoreAppCurrent)-browser</TargetFrameworks>
   </PropertyGroup>
-  <PropertyGroup>
-    <DefineConstants Condition="'$(StabilizePackageVersion)' == 'true'">$(DefineConstants);STABILIZE_PACKAGE_VERSION</DefineConstants>
-  </PropertyGroup>
   <ItemGroup>
     <Compile Include="AssemblyInfo.cs" />
     <Compile Include="CheckArchitectureTests.cs" />