Reverting: Set AssemblyName.ProcessorArchitecture for compatibility. #81101 (#83565)

Author: VSadov

src/libraries/System.Reflection.Metadata/src/System.Reflection.Metadata.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>$(NetCoreAppCurrent);$(NetCoreAppMinimum);netstandard2.0;$(NetFrameworkMinimum)</TargetFrameworks>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
@@ -9,8 +9,8 @@
 
 The System.Reflection.Metadata library is built-in as part of the shared framework in .NET Runtime. The package can be installed when you need to use it in other target frameworks.</PackageDescription>
     <PackageReadmeFile>README.md</PackageReadmeFile>
-    <ServicingVersion>1</ServicingVersion>
-    <GeneratePackageOnBuild>false</GeneratePackageOnBuild>
+    <ServicingVersion>2</ServicingVersion>
+    <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
   </PropertyGroup>
 
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->

src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/MetadataReader.netstandard.cs

@@ -85,12 +85,6 @@ public static unsafe AssemblyName GetAssemblyName(string assemblyFile)
                     peReader = new PEReader((byte*)safeBuffer.DangerousGetHandle(), (int)safeBuffer.ByteLength);
                     MetadataReader mdReader = peReader.GetMetadataReader(MetadataReaderOptions.None);
                     AssemblyName assemblyName = mdReader.GetAssemblyDefinition().GetAssemblyName();
-
-                    AssemblyFlags aFlags = mdReader.AssemblyTable.GetFlags();
-#pragma warning disable SYSLIB0037 // AssemblyName.ProcessorArchitecture is obsolete
-                    assemblyName.ProcessorArchitecture = CalculateProcArch(peReader, aFlags);
-#pragma warning restore SYSLIB0037
-
                     return assemblyName;
                 }
                 finally
@@ -107,42 +101,6 @@ public static unsafe AssemblyName GetAssemblyName(string assemblyFile)
             }
         }
 
-        private static ProcessorArchitecture CalculateProcArch(PEReader peReader, AssemblyFlags aFlags)
-        {
-            // 0x70 specifies "reference assembly".
-            // For these, CLR wants to return None as arch so they can be always loaded, regardless of process type.
-            if (((uint)aFlags & 0xF0) == 0x70)
-                return ProcessorArchitecture.None;
-
-            PEHeaders peHeaders = peReader.PEHeaders;
-            switch (peHeaders.CoffHeader.Machine)
-            {
-                case Machine.IA64:
-                    return ProcessorArchitecture.IA64;
-                case Machine.Arm:
-                    return ProcessorArchitecture.Arm;
-                case Machine.Amd64:
-                    return ProcessorArchitecture.Amd64;
-                case Machine.I386:
-                    {
-                        CorFlags flags = peHeaders.CorHeader!.Flags;
-                        if ((flags & CorFlags.ILOnly) != 0 &&
-                            (flags & CorFlags.Requires32Bit) == 0)
-                        {
-                            // platform neutral.
-                            return ProcessorArchitecture.MSIL;
-                        }
-
-                        // requires x86
-                        return ProcessorArchitecture.X86;
-                    }
-            }
-
-            // ProcessorArchitecture is a legacy API and does not cover other Machine kinds.
-            // For example ARM64 is not expressible
-            return ProcessorArchitecture.None;
-        }
-
         private static AssemblyNameFlags GetAssemblyNameFlags(AssemblyFlags flags)
         {
             AssemblyNameFlags assemblyNameFlags = AssemblyNameFlags.None;

src/libraries/System.Reflection.Metadata/tests/Metadata/MetadataReaderTests.cs

@@ -3090,13 +3090,8 @@ public void GetAssemblyName()
 
             if (PlatformDetection.HasAssemblyFiles)
             {
-                Assembly a = typeof(MetadataReader).Assembly;
-                AssemblyName name = MetadataReader.GetAssemblyName(AssemblyPathHelper.GetAssemblyLocation(a));
-                Assert.Equal(new AssemblyName(a.FullName).ToString(), name.ToString());
-
-#pragma warning disable SYSLIB0037 // AssemblyName.ProcessorArchitecture is obsolete
-                Assert.Equal(ProcessorArchitecture.MSIL, name.ProcessorArchitecture);
-#pragma warning restore SYSLIB0037
+                Assembly a = typeof(MetadataReaderTests).Assembly;
+                Assert.Equal(new AssemblyName(a.FullName).ToString(), MetadataReader.GetAssemblyName(AssemblyPathHelper.GetAssemblyLocation(a)).ToString());
             }
         }
     }