Add NetCoreAppCurrent rid agnostic tfm to libs

src/libraries/System.Console/src/Resources/Strings.resx

@@ -254,4 +254,7 @@
   <data name="IO_TermInfoInvalidMagicNumber" xml:space="preserve">
     <value>The terminfo database has an invalid magic number: '{0}'.</value>
   </data>
+  <data name="PlatformNotSupported_SystemConsole" xml:space="preserve">
+    <value>System.Console is not supported on this platform.</value>
+  </data>
 </root>

src/libraries/System.Console/src/System.Console.csproj

@@ -1,10 +1,15 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Android;$(NetCoreAppCurrent)-iOS;$(NetCoreAppCurrent)-tvOS;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Android;$(NetCoreAppCurrent)-iOS;$(NetCoreAppCurrent)-tvOS;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)</TargetFrameworks>
     <Nullable>enable</Nullable>
   </PropertyGroup>
-  <ItemGroup>
+  <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
+  <PropertyGroup>
+    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetPlatformIdentifier)' == ''">SR.PlatformNotSupported_SystemConsole</GeneratePlatformNotSupportedAssemblyMessage>
+  </PropertyGroup>
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != ''">
     <Compile Include="System\Console.cs" />
     <Compile Include="System\ConsoleCancelEventArgs.cs" />
     <Compile Include="System\ConsoleColor.cs" />

src/libraries/System.IO.Compression.ZipFile/src/Resources/Strings.resx

@@ -99,4 +99,7 @@
   <data name="UnauthorizedAccess_IODenied_Path" xml:space="preserve">
     <value>Access to the path '{0}' is denied.</value>
   </data>
+  <data name="PlatformNotSupported_CompressionZipFile" xml:space="preserve">
+    <value>System.IO.Compression.ZipFile is not supported on this platform.</value>
+  </data>
 </root>

src/libraries/System.IO.Compression.ZipFile/src/System.IO.Compression.ZipFile.csproj

@@ -1,10 +1,15 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)</TargetFrameworks>
     <Nullable>enable</Nullable>
   </PropertyGroup>
-  <ItemGroup>
+  <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
+  <PropertyGroup>
+    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetPlatformIdentifier)' == ''">SR.PlatformNotSupported_CompressionZipFile</GeneratePlatformNotSupportedAssemblyMessage>
+  </PropertyGroup>
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != ''">
     <Compile Include="System\IO\Compression\ZipFile.Create.cs" />
     <Compile Include="System\IO\Compression\ZipFile.Extract.cs" />
     <Compile Include="System\IO\Compression\ZipFile.Utils.cs" />

src/libraries/System.IO.Compression/src/Resources/Strings.resx

@@ -302,4 +302,7 @@
   <data name="EntryNameAlreadyExists" xml:space="preserve">
     <value>An entry named '{0}' already exists in the archive.</value>
   </data>
+  <data name="PlatformNotSupported_Compression" xml:space="preserve">
+    <value>System.IO.Compression is not supported on this platform.</value>
+  </data>
 </root>

src/libraries/System.IO.Compression/src/System.IO.Compression.csproj

@@ -1,10 +1,15 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)</TargetFrameworks>
     <Nullable>enable</Nullable>
   </PropertyGroup>
-  <ItemGroup>
+  <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
+  <PropertyGroup>
+    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetPlatformIdentifier)' == ''">SR.PlatformNotSupported_Compression</GeneratePlatformNotSupportedAssemblyMessage>
+  </PropertyGroup>
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != ''">
     <Compile Include="$(CommonPath)Interop\Interop.zlib.cs" />
     <Compile Include="$(SharedOpenSourcePath)System\IO\Compression\ZipArchive.cs" />
     <Compile Include="$(SharedOpenSourcePath)System\IO\Compression\ZipArchiveEntry.cs" />

src/libraries/System.IO.FileSystem.DriveInfo/src/Resources/Strings.resx

@@ -176,4 +176,7 @@
   <data name="IO_PathTooLong_Path" xml:space="preserve">
     <value>The path '{0}' is too long, or a component of the specified path is too long.</value>
   </data>
+  <data name="PlatformNotSupported_FileSystemDriveInfo" xml:space="preserve">
+    <value>System.IO.FileSystem.DriveInfo is not supported on this platform.</value>
+  </data>
 </root>

src/libraries/System.IO.FileSystem.DriveInfo/src/System.IO.FileSystem.DriveInfo.csproj

@@ -1,10 +1,15 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)</TargetFrameworks>
     <Nullable>enable</Nullable>
   </PropertyGroup>
-  <ItemGroup>
+  <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
+  <PropertyGroup>
+    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetPlatformIdentifier)' == ''">SR.PlatformNotSupported_FileSystemDriveInfo</GeneratePlatformNotSupportedAssemblyMessage>
+  </PropertyGroup>
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != ''">
     <Compile Include="System\IO\DriveInfo.cs" />
     <Compile Include="System\IO\DriveNotFoundException.cs" />
     <Compile Include="System\IO\DriveType.cs" />

src/libraries/System.IO.MemoryMappedFiles/src/Resources/Strings.resx

@@ -219,4 +219,7 @@
   <data name="IO_PathTooLong_Path" xml:space="preserve">
     <value>The path '{0}' is too long, or a component of the specified path is too long.</value>
   </data>
-</root>
+  <data name="PlatformNotSupported_MemoryMappedFiles" xml:space="preserve">
+    <value>System.IO.MemoryMappedFiles is not supported on this platform.</value>
+  </data>
+</root>

src/libraries/System.IO.MemoryMappedFiles/src/System.IO.MemoryMappedFiles.csproj

@@ -2,10 +2,14 @@
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <Nullable>enable</Nullable>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)</TargetFrameworks>
   </PropertyGroup>
-  <!-- Compiled Source Files -->
-  <ItemGroup>
+  <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
+  <PropertyGroup>
+    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetPlatformIdentifier)' == ''">SR.PlatformNotSupported_MemoryMappedFiles</GeneratePlatformNotSupportedAssemblyMessage>
+  </PropertyGroup>
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != ''">
     <Compile Include="Microsoft\Win32\SafeMemoryMappedFileHandle.cs" />
     <Compile Include="Microsoft\Win32\SafeMemoryMappedViewHandle.cs" />
     <Compile Include="System\IO\MemoryMappedFiles\MemoryMappedFileOptions.cs" />

src/libraries/System.Net.Http/src/Resources/Strings.resx

@@ -591,4 +591,7 @@
   <data name="net_http_proxy_tunnel_returned_failure_status_code" xml:space="preserve">
     <value>The proxy tunnel request to proxy '{0}' failed with status code '{1}'."</value>
   </data>
+  <data name="PlatformNotSupported_NetHttp" xml:space="preserve">
+    <value>System.Net.Http is not supported on this platform.</value>
+  </data>
 </root>

src/libraries/System.Net.Http/src/System.Net.Http.csproj

@@ -3,7 +3,7 @@
     <WindowsRID>win</WindowsRID>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <DefineConstants>$(DefineConstants);HTTP_DLL</DefineConstants>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Linux;$(NetCoreAppCurrent)-OSX;$(NetCoreAppCurrent)-FreeBSD;$(NetCoreAppCurrent)-MacCatalyst;$(NetCoreAppCurrent)-iOS;$(NetCoreAppCurrent)-tvOS;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)-illumos;$(NetCoreAppCurrent)-Solaris;$(NetCoreAppCurrent)-Android</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Linux;$(NetCoreAppCurrent)-OSX;$(NetCoreAppCurrent)-FreeBSD;$(NetCoreAppCurrent)-MacCatalyst;$(NetCoreAppCurrent)-iOS;$(NetCoreAppCurrent)-tvOS;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)-illumos;$(NetCoreAppCurrent)-Solaris;$(NetCoreAppCurrent)-Android;$(NetCoreAppCurrent)</TargetFrameworks>
     <Nullable>enable</Nullable>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(TargetsOSX)' == 'true' or '$(TargetsiOS)' == 'true' or '$(TargetstvOS)' == 'true' or '$(TargetsMacCatalyst)' == 'true'">
@@ -31,21 +31,29 @@
   <PropertyGroup>
     <ILLinkDirectory>$(MSBuildThisFileDirectory)ILLink\</ILLinkDirectory>
   </PropertyGroup>
+  <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
+  <PropertyGroup>
+    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetPlatformIdentifier)' == ''">SR.PlatformNotSupported_NetHttp</GeneratePlatformNotSupportedAssemblyMessage>
+  </PropertyGroup>
   <ItemGroup>
     <ILLinkSubstitutionsXmls Include="$(ILLinkDirectory)ILLink.Substitutions.xml" />
     <ILLinkSubstitutionsXmls Condition="'$(TargetsAndroid)' == 'true' or '$(TargetsiOS)' == 'true' or '$(TargetsMacCatalyst)' == 'true' or '$(TargetsTVOS)' == 'true'"
                              Include="$(ILLinkDirectory)ILLink.Substitutions.mobile.xml" />
     <ILLinkSuppressionsXmls Condition="'$(TargetsMobile)' == 'true'" Include="$(ILLinkDirectory)ILLink.Suppressions.Mobile.LibraryBuild.xml" />
   </ItemGroup>
-  <ItemGroup>
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != ''">
     <Compile Include="System\Net\Http\ByteArrayContent.cs" />
     <Compile Include="System\Net\Http\ByteArrayHelpers.cs" />
     <Compile Include="System\Net\Http\CancellationHelper.cs" />
     <Compile Include="System\Net\Http\ClientCertificateOption.cs" />
     <Compile Include="System\Net\Http\DelegatingHandler.cs" />
+    <Compile Include="System\Net\Http\DiagnosticsHandler.cs" />
+    <Compile Include="System\Net\Http\DiagnosticsHandlerLoggingStrings.cs" />
     <Compile Include="System\Net\Http\EmptyContent.cs" />
     <Compile Include="System\Net\Http\EmptyReadStream.cs" />
     <Compile Include="System\Net\Http\FormUrlEncodedContent.cs" />
+    <Compile Include="System\Net\Http\GlobalHttpSettings.cs" />
     <Compile Include="System\Net\Http\HeaderEncodingSelector.cs" />
     <Compile Include="System\Net\Http\Headers\KnownHeader.cs" />
     <Compile Include="System\Net\Http\Headers\HttpHeaderType.cs" />
@@ -128,6 +136,7 @@
     <Compile Include="System\Net\Http\Headers\UriHeaderParser.cs" />
     <Compile Include="System\Net\Http\Headers\ViaHeaderValue.cs" />
     <Compile Include="System\Net\Http\Headers\WarningHeaderValue.cs" />
+    <Compile Include="System\Net\Http\SocketsHttpHandler\SocketsHttpPlaintextStreamFilterContext.cs" />
     <Compile Include="$(CommonPath)System\IO\DelegatingStream.cs"
              Link="Common\System\IO\DelegatingStream.cs" />
     <Compile Include="$(CommonPath)System\IO\ReadOnlyMemoryStream.cs"
@@ -140,6 +149,8 @@
              Link="Common\System\Net\HttpDateParser.cs" />
     <Compile Include="$(CommonPath)System\Text\SimpleRegex.cs"
              Link="Common\System\Text\SimpleRegex.cs" />
+    <Compile Include="$(CommonPath)System\Threading\Tasks\TaskCompletionSourceWithCancellation.cs"
+             Link="Common\System\Threading\Tasks\TaskCompletionSourceWithCancellation.cs" />
     <Compile Include="$(CommonPath)System\HexConverter.cs"
              Link="Common\System\HexConverter.cs" />
     <Compile Include="$(CommonPath)System\Net\ArrayBuffer.cs"
@@ -152,7 +163,7 @@
              Link="Common\System\Net\Http\aspnetcore\Http3\QPack\H3StaticTable.cs" />
   </ItemGroup>
   <!-- SocketsHttpHandler implementation -->
-  <ItemGroup Condition="'$(TargetsBrowser)' != 'true'">
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != '' and '$(TargetsBrowser)' != 'true'">
     <Compile Include="System\Net\Http\HttpHandlerDefaults.cs" />
     <Compile Include="System\Net\Http\HttpMethod.Http3.cs" />
     <Compile Include="System\Net\Http\Headers\AltSvcHeaderParser.cs" />
@@ -521,15 +532,6 @@
     <Compile Include="$(CommonPath)Interop\Windows\SspiCli\SSPIWrapper.cs"
              Link="Common\Interop\Windows\SspiCli\SSPIWrapper.cs" />
   </ItemGroup>
-  <!-- Common -->
-  <ItemGroup>
-    <Compile Include="System\Net\Http\DiagnosticsHandler.cs" />
-    <Compile Include="System\Net\Http\DiagnosticsHandlerLoggingStrings.cs" />
-    <Compile Include="System\Net\Http\GlobalHttpSettings.cs" />
-    <Compile Include="System\Net\Http\SocketsHttpHandler\SocketsHttpPlaintextStreamFilterContext.cs" />
-    <Compile Include="$(CommonPath)System\Threading\Tasks\TaskCompletionSourceWithCancellation.cs"
-             Link="Common\System\Threading\Tasks\TaskCompletionSourceWithCancellation.cs" />
-  </ItemGroup>
   <ItemGroup Condition="'$(TargetsUnix)' == 'true'">
     <Compile Include="$(CommonPath)System\StrongToWeakReference.cs"
              Link="Common\Interop\Unix\StrongToWeakReference.cs" />

src/libraries/System.Net.Mail/src/Resources/Strings.resx

@@ -328,4 +328,7 @@
   <data name="SmtpGetIisPickupDirectoryNotSupported" xml:space="preserve">
     <value>IIS delivery is not supported.</value>
   </data>
+  <data name="PlatformNotSupported_NetMail" xml:space="preserve">
+    <value>System.Net.Mail is not supported on this platform.</value>
+  </data>
 </root>

src/libraries/System.Net.Mail/src/System.Net.Mail.csproj

@@ -1,12 +1,16 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)-tvOS</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)-tvOS;$(NetCoreAppCurrent)</TargetFrameworks>
     <Nullable>enable</Nullable>
     <DefineConstants Condition="'$(TargetstvOS)' == 'true'">$(DefineConstants);NO_NTAUTHENTICATION</DefineConstants>
   </PropertyGroup>
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
-  <ItemGroup>
+  <PropertyGroup>
+    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetPlatformIdentifier)' == ''">SR.PlatformNotSupported_NetMail</GeneratePlatformNotSupportedAssemblyMessage>
+  </PropertyGroup>
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != ''">
     <Compile Include="System\Net\Base64Stream.cs" />
     <Compile Include="System\Net\Mime\MimePart.cs" />
     <Compile Include="System\Net\Mime\Base64WriteStateInfo.cs" />
@@ -77,7 +81,7 @@
   </ItemGroup>
 
   <!-- Non Browser specific files - internal and security -->
-  <ItemGroup Condition="'$(TargetsBrowser)' != 'true'">
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != '' and '$(TargetsBrowser)' != 'true'">
     <Compile Include="System\Net\Mail\SmtpClient.cs" />
     <Compile Include="System\Net\Mail\ISmtpAuthenticationModule.cs" />
     <Compile Include="System\Net\Mail\SmtpAuthenticationManager.cs" />
@@ -115,7 +119,7 @@
   </ItemGroup>
 
   <!-- NT authentication specific files -->
-  <ItemGroup Condition="'$(TargetsBrowser)' != 'true' and '$(TargetstvOS)' != 'true'">
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != '' and '$(TargetsBrowser)' != 'true' and '$(TargetstvOS)' != 'true'">
     <Compile Include="$(CommonPath)System\Net\ContextFlagsPal.cs"
              Link="Common\System\Net\ContextFlagsPal.cs" />
     <Compile Include="$(CommonPath)System\Net\NegotiationInfoClass.cs"

src/libraries/System.Net.NameResolution/src/System.Net.NameResolution.csproj

@@ -1,14 +1,16 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)</TargetFrameworks>
     <Nullable>enable</Nullable>
   </PropertyGroup>
+  <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
   <PropertyGroup>
-    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetsBrowser)' == 'true'">SR.SystemNetNameResolution_PlatformNotSupported</GeneratePlatformNotSupportedAssemblyMessage>
+    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetPlatformIdentifier)' == 'Browser' or '$(TargetPlatformIdentifier)' == ''">SR.SystemNetNameResolution_PlatformNotSupported</GeneratePlatformNotSupportedAssemblyMessage>
     <ApiExclusionListPath Condition="'$(TargetsBrowser)' == 'true'">ExcludeApiList.PNSE.Browser.txt</ApiExclusionListPath>
   </PropertyGroup>
-  <ItemGroup Condition="'$(TargetsBrowser)' != 'true'">
+  <ItemGroup Condition="'$(GeneratePlatformNotSupportedAssemblyMessage)' == ''">
     <Compile Include="System\Net\Dns.cs" />
     <Compile Include="System\Net\IPHostEntry.cs" />
     <Compile Include="System\Net\NetEventSource.NameResolution.cs" />

src/libraries/System.Net.Primitives/src/Resources/Strings.resx

@@ -114,4 +114,7 @@
   <data name="bad_endpoint_string" xml:space="preserve">
     <value>An invalid IPEndPoint was specified.</value>
   </data>
+  <data name="PlatformNotSupported_NetPrimitives" xml:space="preserve">
+    <value>System.Net.Primitives is not supported on this platform.</value>
+  </data>
 </root>

src/libraries/System.Net.Primitives/src/System.Net.Primitives.csproj

@@ -2,15 +2,18 @@
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <ILLinkKeepDepAttributes>false</ILLinkKeepDepAttributes> <!-- See comments in Cookie.cs -->
-    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser;$(NetCoreAppCurrent)</TargetFrameworks>
     <Nullable>enable</Nullable>
-  </PropertyGroup>
-  <PropertyGroup>
     <!-- SYSTEM_NET_PRIMITIVES_DLL is required to allow source-level code sharing for types defined within the
          System.Net.Internals namespace. -->
     <DefineConstants>$(DefineConstants);SYSTEM_NET_PRIMITIVES_DLL</DefineConstants>
   </PropertyGroup>
-  <ItemGroup>
+  <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
+  <PropertyGroup>
+    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <GeneratePlatformNotSupportedAssemblyMessage Condition="'$(TargetPlatformIdentifier)' == ''">SR.PlatformNotSupported_NetPrimitives</GeneratePlatformNotSupportedAssemblyMessage>
+  </PropertyGroup>
+  <ItemGroup Condition="'$(TargetPlatformIdentifier)' != ''">
     <Compile Include="System\Net\AuthenticationSchemes.cs" />
     <Compile Include="System\Net\Cookie.cs" />
     <Compile Include="System\Net\CookieContainer.cs" />