dotnet · radekdoulik · Apr 24, 2026 · Apr 26, 2026 · Apr 27, 2026 · Apr 28, 2026
diff --git a/eng/liveBuilds.targets b/eng/liveBuilds.targets
@@ -244,6 +244,11 @@
         $(LibrariesSharedFrameworkDir)*.js;
         $(LibrariesSharedFrameworkDir)*.a;
         $(LibrariesSharedFrameworkDir)*.dat;
+        "
+        IsNative="true" />
+
+      <LibrariesRuntimeFiles Condition="'$(TargetOS)' == 'browser' and '$(RuntimeFlavor)' == 'CoreCLR' and Exists('$(HostSharedFrameworkDir)libBrowserHost.a')"
+                             Include="
         $(HostSharedFrameworkDir)libBrowserHost.a;
         $(HostSharedFrameworkDir)dotnet.native.js;
         $(HostSharedFrameworkDir)dotnet.native.wasm;

diff --git a/eng/pipelines/coreclr/ci.yml b/eng/pipelines/coreclr/ci.yml
@@ -118,6 +118,32 @@ extends:
                 parameters:
                   testGroup: outerloop
 
+      - template: /eng/pipelines/common/platform-matrix.yml
+        parameters:
+          jobTemplate: /eng/pipelines/common/global-build-job.yml
+          buildConfig: checked
+          platforms:
+          - browser_wasm
+          jobParameters:
+            buildArgs: -s clr+libs -c $(_BuildConfig) -lc Release
+            postBuildSteps:
+              - template: /eng/pipelines/coreclr/templates/build-native-test-assets-step.yml
+                parameters:
+                  extraBuildArgs: -os browser
+              - template: /eng/pipelines/common/upload-artifact-step.yml
+                parameters:
+                  rootFolder: $(Build.SourcesDirectory)/artifacts/bin
+                  includeRootFolder: false
+                  archiveType: $(archiveType)
+                  archiveExtension: $(archiveExtension)
+                  tarCompression: $(tarCompression)
+                  artifactName: BuildArtifacts_$(osGroup)$(osSubgroup)_$(archType)_$(_BuildConfig)
+                  displayName: Build Assets
+            extraVariablesTemplates:
+              - template: /eng/pipelines/common/templates/runtimes/native-test-assets-variables.yml
+                parameters:
+                  testGroup: outerloop
+
       #
       # Checked test builds
       #
@@ -148,6 +174,23 @@ extends:
             liveLibrariesBuildConfig: Release
             unifiedArtifactsName: BuildArtifacts_$(osGroup)$(osSubgroup)_$(archType)_$(_BuildConfig)
 
+      #
+      # Checked interpreter test runs
+      #
+      - template: /eng/pipelines/common/platform-matrix.yml
+        parameters:
+          jobTemplate: /eng/pipelines/common/templates/runtimes/run-test-job.yml
+          buildConfig: checked
+          platforms:
+          - browser_wasm
+          helixQueueGroup: ci
+          helixQueuesTemplate: /eng/pipelines/coreclr/templates/helix-queues-setup.yml
+          jobParameters:
+            testGroup: outerloop
+            liveLibrariesBuildConfig: Release
+            unifiedArtifactsName: BuildArtifacts_$(osGroup)$(osSubgroup)_$(archType)_$(_BuildConfig)
+            extraBuildArgs: -os browser -p:HostConfiguration=Release
+
       #
       # Checked R2R test runs
       #

diff --git a/src/tests/CoreMangLib/CoreMangLib.csproj b/src/tests/CoreMangLib/CoreMangLib.csproj
@@ -7,6 +7,9 @@
     <MergedWrapperProjectReference Include="system/buffer/Asurt_99893.csproj" />
     <Compile Include="**/*.cs" Exclude="system/buffer/Asurt_99893.cs" />
   </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="$(TestLibraryProjectPath)" />
+  </ItemGroup>
 
   <Import Project="$(TestSourceDir)MergedTestRunner.targets" />
 </Project>
diff --git a/src/tests/CoreMangLib/system/span/RefStructWithSpan.cs b/src/tests/CoreMangLib/system/span/RefStructWithSpan.cs
@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.Threading;
 using Xunit;
+using TestLibrary;
 
 ref struct MyStruct<A, B>
 {
@@ -70,7 +71,7 @@ static void Churn()
 
     public static int[][] g = new int[10000][];
 
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("Incompatible with GC stress", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/JIT/Directed/tailcall/mutual_recursion.fs b/src/tests/JIT/Directed/tailcall/mutual_recursion.fs
@@ -556,6 +556,7 @@ type Driver() =
 ////////////////////////////////////////////////////////////////////////////////
 ////////////////////////////////////////////////////////////////////////////////
 
+[<ActiveIssue("https://github.com/dotnet/runtime/issues/127437", typeof<PlatformDetection>, [| "IsBrowser" |])>]
 [<SkipOnCoreClr("Unstable under JIT stress", RuntimeTestModes.AnyJitStress ||| RuntimeTestModes.AnyGCStress)>]
 [<SkipOnMono("Not supported on Mono runtime")>]
 [<ConditionalFact(typeof<Utilities>, [| "IsNotNativeAot" |])>]

diff --git a/src/tests/JIT/Methodical/Methodical_d2.csproj b/src/tests/JIT/Methodical/Methodical_d2.csproj
@@ -10,6 +10,11 @@
     <MergedWrapperProjectReference Remove="c*/**/*_d.??proj" />
     <MergedWrapperProjectReference Remove="d*/**/*_d.??proj" />
     <MergedWrapperProjectReference Remove="e*/**/*_d.??proj" />
+    <!-- https://github.com/dotnet/runtime/issues/127426 - TypeLoadException on WASM interpreter, regression from #126901 -->
+    <MergedWrapperProjectReference Condition="'$(TargetOS)' == 'browser'" Remove="VT/callconv/aa_d.ilproj" />
+    <MergedWrapperProjectReference Condition="'$(TargetOS)' == 'browser'" Remove="VT/callconv/calli_d.ilproj" />
+    <MergedWrapperProjectReference Condition="'$(TargetOS)' == 'browser'" Remove="VT/callconv/dd_d.ilproj" />
+    <MergedWrapperProjectReference Condition="'$(TargetOS)' == 'browser'" Remove="VT/callconv/ee_d.ilproj" />
     <ProjectReference Include="../common/localloc_common.ilproj" />
     <ProjectReference Include="../common/eh_common.csproj" />
     <ProjectReference Include="int64/unsigned/implicit_promotion_il.ilproj" />
@@ -123,7 +128,9 @@
     <Compile Include="unsafecsharp\unsafe-4.cs" />
     <Compile Include="unsafecsharp\unsafe-5.cs" />
     <Compile Include="unsafecsharp\unsafe-6.cs" />
-    <Compile Include="VT\callconv\call.cs" />
+
+    <!-- https://github.com/dotnet/runtime/issues/127426 - TypeLoadException on WASM interpreter, regression from #126901 -->
+    <Compile Include="VT\callconv\call.cs" Condition="'$(TargetOS)' != 'browser'" />
     <Compile Include="VT\callconv\jumper.cs" />
     <Compile Include="VT\callconv\jumps.cs" />
     <Compile Include="VT\callconv\vtret.cs" />

diff --git a/src/tests/JIT/Methodical/Methodical_do.csproj b/src/tests/JIT/Methodical/Methodical_do.csproj
@@ -261,7 +261,8 @@
     <Compile Include="unsafecsharp\unsafe-4.cs" />
     <Compile Include="unsafecsharp\unsafe-5.cs" />
     <Compile Include="unsafecsharp\unsafe-6.cs" />
-    <Compile Include="VT\callconv\call.cs" />
+    <!-- https://github.com/dotnet/runtime/issues/127426 — TypeLoadException for struct implementing interface on interpreter -->
+    <Compile Include="VT\callconv\call.cs" Condition="'$(TargetOS)' != 'browser'" />
     <Compile Include="VT\callconv\jumper.cs" />
     <Compile Include="VT\callconv\jumps.cs" />
     <Compile Include="VT\callconv\vtret.cs" />

diff --git a/src/tests/JIT/Methodical/Methodical_r2.csproj b/src/tests/JIT/Methodical/Methodical_r2.csproj
@@ -10,6 +10,11 @@
     <MergedWrapperProjectReference Remove="c*/**/*_r.??proj" />
     <MergedWrapperProjectReference Remove="d*/**/*_r.??proj" />
     <MergedWrapperProjectReference Remove="e*/**/*_r.??proj" />
+    <!-- https://github.com/dotnet/runtime/issues/127426 - TypeLoadException on WASM interpreter, regression from #126901 -->
+    <MergedWrapperProjectReference Condition="'$(TargetOS)' == 'browser'" Remove="VT/callconv/aa_r.ilproj" />
+    <MergedWrapperProjectReference Condition="'$(TargetOS)' == 'browser'" Remove="VT/callconv/calli_r.ilproj" />
+    <MergedWrapperProjectReference Condition="'$(TargetOS)' == 'browser'" Remove="VT/callconv/dd_r.ilproj" />
+    <MergedWrapperProjectReference Condition="'$(TargetOS)' == 'browser'" Remove="VT/callconv/ee_r.ilproj" />
     <ProjectReference Include="../common/localloc_common.ilproj" />
     <ProjectReference Include="../common/eh_common.csproj" />
     <ProjectReference Include="int64/unsigned/implicit_promotion_il.ilproj" />
@@ -123,7 +128,8 @@
     <Compile Include="unsafecsharp\unsafe-4.cs" />
     <Compile Include="unsafecsharp\unsafe-5.cs" />
     <Compile Include="unsafecsharp\unsafe-6.cs" />
-    <Compile Include="VT\callconv\call.cs" />
+    <!-- https://github.com/dotnet/runtime/issues/127426 — TypeLoadException for struct implementing interface on interpreter -->
+    <Compile Include="VT\callconv\call.cs" Condition="'$(TargetOS)' != 'browser'" />
     <Compile Include="VT\callconv\jumper.cs" />
     <Compile Include="VT\callconv\jumps.cs" />
     <Compile Include="VT\callconv\vtret.cs" />

diff --git a/src/tests/JIT/Methodical/Methodical_ro.csproj b/src/tests/JIT/Methodical/Methodical_ro.csproj
@@ -261,7 +261,8 @@
     <Compile Include="unsafecsharp\unsafe-4.cs" />
     <Compile Include="unsafecsharp\unsafe-5.cs" />
     <Compile Include="unsafecsharp\unsafe-6.cs" />
-    <Compile Include="VT\callconv\call.cs" />
+    <!-- https://github.com/dotnet/runtime/issues/127426 — TypeLoadException for struct implementing interface on interpreter -->
+    <Compile Include="VT\callconv\call.cs" Condition="'$(TargetOS)' != 'browser'" />
     <Compile Include="VT\callconv\jumper.cs" />
     <Compile Include="VT\callconv\jumps.cs" />
     <Compile Include="VT\callconv\vtret.cs" />

diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest.csproj b/src/tests/JIT/jit64/opt/cse/VolatileTest.csproj
@@ -10,4 +10,7 @@
     <Compile Include="VolatileTest_op_and.cs" />
     <Compile Include="VolatileTest_op_shr.cs" />
   </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="$(TestLibraryProjectPath)" />
+  </ItemGroup>
 </Project>
diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest_op_add.cs b/src/tests/JIT/jit64/opt/cse/VolatileTest_op_add.cs
@@ -7,12 +7,13 @@
 using System.Threading;
 using System.Text;
 using Xunit;
+using TestLibrary;
 
 namespace JIT.jit64.opt.cse.VolatileTest_op_add;
 
 public class Program
 {
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest_op_and.cs b/src/tests/JIT/jit64/opt/cse/VolatileTest_op_and.cs
@@ -7,12 +7,13 @@
 using System.Threading;
 using System.Text;
 using Xunit;
+using TestLibrary;
 
 namespace JIT.jit64.opt.cse.VolatileTest_op_and;
 
 public class Program
 {
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest_op_div.cs b/src/tests/JIT/jit64/opt/cse/VolatileTest_op_div.cs
@@ -7,12 +7,13 @@
 using System.Threading;
 using System.Text;
 using Xunit;
+using TestLibrary;
 
 namespace JIT.jit64.opt.cse.VolatileTest_op_div;
 
 public class Program
 {
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest_op_mod.cs b/src/tests/JIT/jit64/opt/cse/VolatileTest_op_mod.cs
@@ -7,12 +7,13 @@
 using System.Threading;
 using System.Text;
 using Xunit;
+using TestLibrary;
 
 namespace JIT.jit64.opt.cse.VolatileTest_op_mod;
 
 public class Program
 {
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest_op_mul.cs b/src/tests/JIT/jit64/opt/cse/VolatileTest_op_mul.cs
@@ -7,12 +7,13 @@
 using System.Threading;
 using System.Text;
 using Xunit;
+using TestLibrary;
 
 namespace JIT.jit64.opt.cse.VolatileTest_op_mul;
 
 public class Program
 {
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest_op_or.cs b/src/tests/JIT/jit64/opt/cse/VolatileTest_op_or.cs
@@ -7,12 +7,13 @@
 using System.Threading;
 using System.Text;
 using Xunit;
+using TestLibrary;
 
 namespace JIT.jit64.opt.cse.VolatileTest_op_or;
 
 public class Program
 {
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest_op_shr.cs b/src/tests/JIT/jit64/opt/cse/VolatileTest_op_shr.cs
@@ -7,12 +7,13 @@
 using System.Threading;
 using System.Text;
 using Xunit;
+using TestLibrary;
 
 namespace JIT.jit64.opt.cse.VolatileTest_op_shr;
 
 public class Program
 {
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest_op_sub.cs b/src/tests/JIT/jit64/opt/cse/VolatileTest_op_sub.cs
@@ -7,12 +7,13 @@
 using System.Threading;
 using System.Text;
 using Xunit;
+using TestLibrary;
 
 namespace JIT.jit64.opt.cse.VolatileTest_op_sub;
 
 public class Program
 {
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/JIT/jit64/opt/cse/VolatileTest_op_xor.cs b/src/tests/JIT/jit64/opt/cse/VolatileTest_op_xor.cs
@@ -7,12 +7,13 @@
 using System.Threading;
 using System.Text;
 using Xunit;
+using TestLibrary;
 
 namespace JIT.jit64.opt.cse.VolatileTest_op_xor;
 
 public class Program
 {
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     [OuterLoop]
     [SkipOnCoreClr("", RuntimeTestModes.AnyGCStress)]
     public static int TestEntryPoint()

diff --git a/src/tests/Loader/classloader/MethodImpl/Desktop/self_override5.il b/src/tests/Loader/classloader/MethodImpl/Desktop/self_override5.il
@@ -79,6 +79,7 @@
         01 00 00 00
     )
     .custom instance void [Microsoft.DotNet.XUnitExtensions]Xunit.ActiveIssueAttribute::.ctor(string, class [mscorlib]System.Type, string[]) = {string('Tests that expect TypeLoadException') type([TestLibrary]TestLibrary.Utilities) string[1] ('IsNativeAot') }
+    .custom instance void [Microsoft.DotNet.XUnitExtensions]Xunit.ActiveIssueAttribute::.ctor(string, class [mscorlib]System.Type, string[]) = {string('https://github.com/dotnet/runtime/issues/120708') type([TestLibrary]TestLibrary.PlatformDetection) string[1] ('IsBrowser') }
     .entrypoint
 
     .locals init (bool V_0,