diff --git a/src/libraries/Microsoft.CSharp/tests/AssignmentTests.cs b/src/libraries/Microsoft.CSharp/tests/AssignmentTests.cs
index 1c9d3fc784cadb..db59578a9babaf 100644
--- a/src/libraries/Microsoft.CSharp/tests/AssignmentTests.cs
+++ b/src/libraries/Microsoft.CSharp/tests/AssignmentTests.cs
@@ -83,7 +83,7 @@ public void AddAssignment(dynamic lhs, dynamic rhs, object expected)
         {
             lhs += rhs;
             Assert.Equal(expected, lhs);
-            Assert.IsType(expected.GetType(), lhs);
+            Assert.IsType(expected.GetType(), (object)lhs);
         }
 
         [Theory, MemberData(nameof(PropertyAdditions))]
diff --git a/src/libraries/Microsoft.CSharp/tests/ILLink.Descriptors.xml b/src/libraries/Microsoft.CSharp/tests/ILLink.Descriptors.xml
deleted file mode 100644
index b438257bdcaac9..00000000000000
--- a/src/libraries/Microsoft.CSharp/tests/ILLink.Descriptors.xml
+++ /dev/null
@@ -1,7 +0,0 @@
-<linker>
-  <assembly fullname="xunit.assert">
-    <type fullname="Xunit.Assert">
-      <method name="IsType" />
-    </type>
-  </assembly>
-</linker>
diff --git a/src/libraries/Microsoft.CSharp/tests/Microsoft.CSharp.Tests.csproj b/src/libraries/Microsoft.CSharp/tests/Microsoft.CSharp.Tests.csproj
index c180a1efa25146..560b908e3c42d6 100644
--- a/src/libraries/Microsoft.CSharp/tests/Microsoft.CSharp.Tests.csproj
+++ b/src/libraries/Microsoft.CSharp/tests/Microsoft.CSharp.Tests.csproj
@@ -11,7 +11,6 @@
     <DebuggerSupport Condition="'$(DebuggerSupport)' == '' and ('$(TargetOS)' == 'browser' or '$(TargetOS)' == 'wasi')">true</DebuggerSupport>
   </PropertyGroup>
   <ItemGroup>
-    <TrimmerRootDescriptor Include="$(MSBuildThisFileDirectory)ILLink.Descriptors.xml" />
     <Compile Include="$(CoreLibSharedDir)System\Runtime\CompilerServices\IsExternalInit.cs" Link="Common\System\Runtime\CompilerServices\IsExternalInit.cs" />
     <Compile Include="AccessTests.cs" />
     <Compile Include="ArrayHandling.cs" />