diff --git a/eng/generators.targets b/eng/generators.targets
index aec6e667a6efdb..4e7d7b99b44031 100644
--- a/eng/generators.targets
+++ b/eng/generators.targets
@@ -10,10 +10,7 @@
     <!-- If the current project is not System.Private.CoreLib, we enable the DllImportGenerator source generator
          when the project is a C# source project that either:
          - references System.Private.CoreLib, or
-         - references the following assemblies:
-          - System.Runtime.InteropServices
-          - System.Runtime.CompilerServices.Unsafe
-          - System.Memory -->
+         - references System.Runtime.InteropServices -->
     <EnabledGenerators Include="DllImportGenerator"
                        Condition="'$(EnableDllImportGenerator)' == ''
                         and '$(IsFrameworkSupportFacade)' != 'true'
@@ -21,11 +18,7 @@
                         and '$(MSBuildProjectExtension)' == '.csproj'
                         and (
                           ('@(Reference)' != ''
-                            and @(Reference->AnyHaveMetadataValue('Identity', 'System.Runtime.InteropServices'))
-                            and (@(Reference->AnyHaveMetadataValue('Identity', 'System.Runtime.CompilerServices.Unsafe'))
-                              or ('@(ProjectReference)' != ''
-                                and @(ProjectReference->AnyHaveMetadataValue('Identity', $([MSBuild]::NormalizePath('$(LibrariesProjectRoot)', 'System.Runtime.CompilerServices.Unsafe', 'src', 'System.Runtime.CompilerServices.Unsafe.ilproj'))))))
-                            and @(Reference->AnyHaveMetadataValue('Identity', 'System.Memory')))
+                            and @(Reference->AnyHaveMetadataValue('Identity', 'System.Runtime.InteropServices')))
                           or ('@(ProjectReference)' != ''
                             and @(ProjectReference->AnyHaveMetadataValue('Identity', '$(CoreLibProject)'))))" />
     <EnabledGenerators Include="DllImportGenerator"
@@ -45,7 +38,19 @@
 
     <!-- Only add the following files if we are on the latest TFM (that is, net7). -->
     <Compile Condition="'$(NetCoreAppCurrentTargetFrameworkMoniker)' == '$(TargetFrameworkMoniker)'" Include="$(LibrariesProjectRoot)Common\src\System\Runtime\InteropServices\GeneratedMarshallingAttribute.cs" />
-    <Compile Condition="'$(NetCoreAppCurrentTargetFrameworkMoniker)' == '$(TargetFrameworkMoniker)'" Include="$(LibrariesProjectRoot)Common\src\System\Runtime\InteropServices\ArrayMarshaller.cs" />
+
+    <!-- Only add the following files if we are on the latest TFM (that is, net7) and the project is SPCL or has references to System.Runtime.CompilerServices.Unsafe and System.Memory -->
+    <Compile Condition="'$(NetCoreAppCurrentTargetFrameworkMoniker)' == '$(TargetFrameworkMoniker)'
+                        and (
+                          '$(MSBuildProjectName)' == 'System.Private.CoreLib'
+                          or '$(EnableDllImportGenerator)' == 'true'
+                          or ('@(Reference)' != ''
+                            and (@(Reference->AnyHaveMetadataValue('Identity', 'System.Runtime.CompilerServices.Unsafe'))
+                              or ('@(ProjectReference)' != ''
+                                and @(ProjectReference->AnyHaveMetadataValue('Identity', $([MSBuild]::NormalizePath('$(LibrariesProjectRoot)', 'System.Runtime.CompilerServices.Unsafe', 'src', 'System.Runtime.CompilerServices.Unsafe.ilproj'))))))
+                            and @(Reference->AnyHaveMetadataValue('Identity', 'System.Memory')))
+                          or ('@(ProjectReference)' != ''
+                            and @(ProjectReference->AnyHaveMetadataValue('Identity', '$(CoreLibProject)'))))" Include="$(LibrariesProjectRoot)Common\src\System\Runtime\InteropServices\ArrayMarshaller.cs" />
   </ItemGroup>
 
   <Target Name="ConfigureGenerators"
diff --git a/src/libraries/System.DirectoryServices.AccountManagement/src/System.DirectoryServices.AccountManagement.csproj b/src/libraries/System.DirectoryServices.AccountManagement/src/System.DirectoryServices.AccountManagement.csproj
index 22917a6803eb2f..7bcd2a56a94d6a 100644
--- a/src/libraries/System.DirectoryServices.AccountManagement/src/System.DirectoryServices.AccountManagement.csproj
+++ b/src/libraries/System.DirectoryServices.AccountManagement/src/System.DirectoryServices.AccountManagement.csproj
@@ -4,6 +4,7 @@
     <IncludeDllSafeSearchPathAttribute>true</IncludeDllSafeSearchPathAttribute>
     <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent);$(NetCoreAppMinimum)-windows;$(NetCoreAppMinimum);netstandard2.0</TargetFrameworks>
     <NoWarn>$(NoWarn);CA2249</NoWarn>
+    <Nullable>annotations</Nullable>
     <IsPackable>true</IsPackable>
     <AddNETFrameworkPlaceholderFileToPackage>true</AddNETFrameworkPlaceholderFileToPackage>
     <AddNETFrameworkAssemblyReferenceToPackage>true</AddNETFrameworkAssemblyReferenceToPackage>
diff --git a/src/libraries/System.DirectoryServices.Protocols/src/System.DirectoryServices.Protocols.csproj b/src/libraries/System.DirectoryServices.Protocols/src/System.DirectoryServices.Protocols.csproj
index 8ee73ae4c1d284..102c67d81410e3 100644
--- a/src/libraries/System.DirectoryServices.Protocols/src/System.DirectoryServices.Protocols.csproj
+++ b/src/libraries/System.DirectoryServices.Protocols/src/System.DirectoryServices.Protocols.csproj
@@ -4,6 +4,7 @@
     <IncludeDllSafeSearchPathAttribute>true</IncludeDllSafeSearchPathAttribute>
     <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-OSX;$(NetCoreAppCurrent)-Linux;$(NetCoreAppCurrent);$(NetCoreAppMinimum)-windows;$(NetCoreAppMinimum)-OSX;$(NetCoreAppMinimum)-Linux;$(NetCoreAppMinimum);netstandard2.0</TargetFrameworks>
     <IsPackable>true</IsPackable>
+    <Nullable>annotations</Nullable>
     <AddNETFrameworkPlaceholderFileToPackage>true</AddNETFrameworkPlaceholderFileToPackage>
     <AddNETFrameworkAssemblyReferenceToPackage>true</AddNETFrameworkAssemblyReferenceToPackage>
     <PackageDescription>Provides the methods defined in the Lightweight Directory Access Protocol (LDAP) version 3 (V3) and Directory Services Markup Language (DSML) version 2.0 (V2) standards.</PackageDescription>
diff --git a/src/libraries/System.Runtime.InteropServices/gen/DllImportGenerator/PInvokeStubCodeGenerator.cs b/src/libraries/System.Runtime.InteropServices/gen/DllImportGenerator/PInvokeStubCodeGenerator.cs
index 4c9bbd0b1e3920..9eb5f6272a6590 100644
--- a/src/libraries/System.Runtime.InteropServices/gen/DllImportGenerator/PInvokeStubCodeGenerator.cs
+++ b/src/libraries/System.Runtime.InteropServices/gen/DllImportGenerator/PInvokeStubCodeGenerator.cs
@@ -197,6 +197,15 @@ BoundGenerator CreateGenerator(TypePositionInfo p)
             {
                 try
                 {
+                    // TODO: Remove once helper types (like ArrayMarshaller) are part of the runtime
+                    // This check is to help with enabling the source generator for runtime libraries without making each
+                    // library directly reference System.Memory and System.Runtime.CompilerServices.Unsafe unless it needs to
+                    if (p.MarshallingAttributeInfo is MissingSupportMarshallingInfo
+                        && (environment.TargetFramework == TargetFramework.Net && environment.TargetFrameworkVersion.Major >= 7))
+                    {
+                        throw new MarshallingNotSupportedException(p, this);
+                    }
+
                     return new BoundGenerator(p, generatorFactory.Create(p, this));
                 }
                 catch (MarshallingNotSupportedException e)
diff --git a/src/libraries/System.Speech/src/System.Speech.csproj b/src/libraries/System.Speech/src/System.Speech.csproj
index 0a72d5a24dbf7f..783e89d8b0e4bd 100644
--- a/src/libraries/System.Speech/src/System.Speech.csproj
+++ b/src/libraries/System.Speech/src/System.Speech.csproj
@@ -5,6 +5,7 @@
     <!-- CS0649: uninitialized interop type fields -->
     <!-- SA1129: https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/3277 -->
     <NoWarn>$(NoWarn);CS0649;SA1129;CA1847</NoWarn>
+    <Nullable>annotations</Nullable>
     <SetIsTrimmable>false</SetIsTrimmable>
     <IsPackable>true</IsPackable>
     <AddNETFrameworkPlaceholderFileToPackage>true</AddNETFrameworkPlaceholderFileToPackage>