dotnet · radekdoulik · Aug 5, 2026 · Aug 5, 2026
diff --git a/src/tests/GC/API/GC/GetTotalAllocatedBytesServerGC.csproj b/src/tests/GC/API/GC/GetTotalAllocatedBytesServerGC.csproj
@@ -1,12 +1,15 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <!-- Needed for CLRTestEnvironmentVariable and GCStressIncompatible -->
+    <!-- Needed for CLRTestEnvironmentVariable, CLRTestTargetUnsupported, and GCStressIncompatible -->
     <RequiresProcessIsolation>true</RequiresProcessIsolation>
     <CLRTestPriority>1</CLRTestPriority>
     <!-- NativeAOT selects the Server GC implementation at link time -->
     <ServerGarbageCollection>true</ServerGarbageCollection>
     <!-- DATAS heap-count adaptation is a CoreCLR Server GC behavior -->
     <CLRTestTargetUnsupported Condition="'$(RuntimeFlavor)' != 'coreclr'">true</CLRTestTargetUnsupported>
+    <!-- TODO: Re-enable when CoreCLR WebAssembly supports server GC.
+         Tracked by https://github.com/dotnet/runtime/issues/131321. -->
+    <CLRTestTargetUnsupported Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">true</CLRTestTargetUnsupported>
   </PropertyGroup>
   <PropertyGroup>
     <DebugType>PdbOnly</DebugType>

diff --git a/src/tests/GC/API/GC/GetTotalMemoryConcurrent.cs b/src/tests/GC/API/GC/GetTotalMemoryConcurrent.cs
@@ -19,13 +19,14 @@
 using System.Diagnostics;
 using System.Runtime.InteropServices;
 using System.Threading;
+using TestLibrary;
 using Xunit;
 
 public class GetTotalMemoryConcurrent
 {
     private static volatile bool s_stop;
 
-    [Fact]
+    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsMultithreadingSupported))]
     public static void TestEntryPoint()
     {
         // A couple of seconds is far more than enough: the unfixed runtime fails almost immediately

diff --git a/src/tests/GC/API/GC/GetTotalMemoryConcurrent.csproj b/src/tests/GC/API/GC/GetTotalMemoryConcurrent.csproj
@@ -11,4 +11,7 @@
   <ItemGroup>
     <Compile Include="GetTotalMemoryConcurrent.cs" />
   </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="$(TestLibraryProjectPath)" />
+  </ItemGroup>
 </Project>
diff --git a/src/tests/JIT/jit64/regress/ddb/113574/113574.csproj b/src/tests/JIT/jit64/regress/ddb/113574/113574.csproj
@@ -1,9 +1,12 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <!-- Only needed to run GCStress out-of-proc -->
+    <!-- Needed for CLRTestTargetUnsupported and to run GCStress out-of-proc -->
     <RequiresProcessIsolation>true</RequiresProcessIsolation>
 
     <CLRTestPriority>1</CLRTestPriority>
+    <!-- TODO: Re-enable when a WebAssembly JIT or equivalent makes the multi-billion-iteration loop stress practical.
+         Tracked by https://github.com/dotnet/runtime/issues/131321. -->
+    <CLRTestTargetUnsupported Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">true</CLRTestTargetUnsupported>
   </PropertyGroup>
   <PropertyGroup>
     <DebugType>PdbOnly</DebugType>

diff --git a/src/tests/baseservices/TieredCompilation/BasicTest.cs b/src/tests/baseservices/TieredCompilation/BasicTest.cs
@@ -13,9 +13,6 @@ public static class BasicTest
     [ActiveIssue("missing assembly", TestPlatforms.Windows, runtimes: TestRuntimes.Mono)]
     [ActiveIssue("No crossgen folder under Core_Root", TestPlatforms.Android)]
     [ActiveIssue("missing assembly", TestPlatforms.iOS | TestPlatforms.tvOS | TestPlatforms.MacCatalyst)]
-#if BROWSER_WASM_COMPOSITE_R2R_TEST
-    [ActiveIssue("https://github.com/dotnet/runtime/issues/131767", typeof(PlatformDetection), nameof(PlatformDetection.IsBrowser), nameof(PlatformDetection.IsCoreCLR))]
-#endif
     [Fact]
     public static void TestEntryPoint()
     {

diff --git a/src/tests/baseservices/TieredCompilation/BasicTest_DefaultMode_R2r.csproj b/src/tests/baseservices/TieredCompilation/BasicTest_DefaultMode_R2r.csproj
@@ -6,9 +6,7 @@
     <Optimize>true</Optimize>
 
     <!-- This is an explicit crossgen test -->
-    <AlwaysUseCrossGen2 Condition="'$(RuntimeFlavor)' != 'coreclr' or '$(TargetOS)' != 'browser'">true</AlwaysUseCrossGen2>
-    <CrossGenTest Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">false</CrossGenTest>
-    <DefineConstants>$(DefineConstants);BROWSER_WASM_COMPOSITE_R2R_TEST</DefineConstants>
+    <AlwaysUseCrossGen2>true</AlwaysUseCrossGen2>
     <!-- No crossgen folder under Core_Root -->
      <NativeAotIncompatible>true</NativeAotIncompatible>
   </PropertyGroup>

diff --git a/src/tests/baseservices/TieredCompilation/BasicTest_QuickJitForLoopsOff_R2r.csproj b/src/tests/baseservices/TieredCompilation/BasicTest_QuickJitForLoopsOff_R2r.csproj
@@ -6,9 +6,7 @@
     <Optimize>true</Optimize>
 
     <!-- This is an explicit crossgen test -->
-    <AlwaysUseCrossGen2 Condition="'$(RuntimeFlavor)' != 'coreclr' or '$(TargetOS)' != 'browser'">true</AlwaysUseCrossGen2>
-    <CrossGenTest Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">false</CrossGenTest>
-    <DefineConstants>$(DefineConstants);BROWSER_WASM_COMPOSITE_R2R_TEST</DefineConstants>
+    <AlwaysUseCrossGen2>true</AlwaysUseCrossGen2>
     <!-- No crossgen folder under Core_Root -->
      <NativeAotIncompatible>true</NativeAotIncompatible>
   </PropertyGroup>

diff --git a/src/tests/baseservices/TieredCompilation/BasicTest_QuickJitForLoopsOn_R2r.csproj b/src/tests/baseservices/TieredCompilation/BasicTest_QuickJitForLoopsOn_R2r.csproj
@@ -6,9 +6,7 @@
     <Optimize>true</Optimize>
 
     <!-- This is an explicit crossgen test -->
-    <AlwaysUseCrossGen2 Condition="'$(RuntimeFlavor)' != 'coreclr' or '$(TargetOS)' != 'browser'">true</AlwaysUseCrossGen2>
-    <CrossGenTest Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">false</CrossGenTest>
-    <DefineConstants>$(DefineConstants);BROWSER_WASM_COMPOSITE_R2R_TEST</DefineConstants>
+    <AlwaysUseCrossGen2>true</AlwaysUseCrossGen2>
     <!-- No crossgen folder under Core_Root -->
      <NativeAotIncompatible>true</NativeAotIncompatible>
   </PropertyGroup>

diff --git a/src/tests/baseservices/TieredCompilation/BasicTest_QuickJitOff_R2r.csproj b/src/tests/baseservices/TieredCompilation/BasicTest_QuickJitOff_R2r.csproj
@@ -6,9 +6,7 @@
     <Optimize>true</Optimize>
 
     <!-- This is an explicit crossgen test -->
-    <AlwaysUseCrossGen2 Condition="'$(RuntimeFlavor)' != 'coreclr' or '$(TargetOS)' != 'browser'">true</AlwaysUseCrossGen2>
-    <CrossGenTest Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">false</CrossGenTest>
-    <DefineConstants>$(DefineConstants);BROWSER_WASM_COMPOSITE_R2R_TEST</DefineConstants>
+    <AlwaysUseCrossGen2>true</AlwaysUseCrossGen2>
     <!-- No crossgen folder under Core_Root -->
      <NativeAotIncompatible>true</NativeAotIncompatible>
   </PropertyGroup>

diff --git a/src/tests/baseservices/TieredCompilation/BasicTest_QuickJitOn_R2r.csproj b/src/tests/baseservices/TieredCompilation/BasicTest_QuickJitOn_R2r.csproj
@@ -6,9 +6,7 @@
     <Optimize>true</Optimize>
 
     <!-- This is an explicit crossgen test -->
-    <AlwaysUseCrossGen2 Condition="'$(RuntimeFlavor)' != 'coreclr' or '$(TargetOS)' != 'browser'">true</AlwaysUseCrossGen2>
-    <CrossGenTest Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">false</CrossGenTest>
-    <DefineConstants>$(DefineConstants);BROWSER_WASM_COMPOSITE_R2R_TEST</DefineConstants>
+    <AlwaysUseCrossGen2>true</AlwaysUseCrossGen2>
     <!-- No crossgen folder under Core_Root -->
      <NativeAotIncompatible>true</NativeAotIncompatible>
   </PropertyGroup>

diff --git a/src/tests/baseservices/threading/regressions/2164/foreground-shutdown.cs b/src/tests/baseservices/threading/regressions/2164/foreground-shutdown.cs
@@ -3,6 +3,7 @@
 
 using System;
 using System.Threading;
+using TestLibrary;
 
 /*
  * Issue description:
@@ -14,6 +15,12 @@ public class Test_foreground_shutdown
 {
     public static int Main()
     {
+        if (!PlatformDetection.IsMultithreadingSupported)
+        {
+            Console.WriteLine("Multithreading is not supported, skipping test.");
+            return 100;
+        }
+
         new Thread(() =>
         {
             Thread.Sleep(TimeSpan.FromSeconds(2));

diff --git a/src/tests/baseservices/threading/regressions/2164/foreground-shutdown.csproj b/src/tests/baseservices/threading/regressions/2164/foreground-shutdown.csproj
@@ -9,4 +9,7 @@
   <ItemGroup>
     <Compile Include="foreground-shutdown.cs" />
   </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="$(TestLibraryProjectPath)" />
+  </ItemGroup>
 </Project>
diff --git a/src/tests/readytorun/DynamicMethodGCStress/DynamicMethodGCStress.cs b/src/tests/readytorun/DynamicMethodGCStress/DynamicMethodGCStress.cs
@@ -12,7 +12,6 @@
 public static class Program
 {
     [ActiveIssue("timeout", TestPlatforms.Any)]
-    [ActiveIssue("https://github.com/dotnet/runtime/issues/131767", typeof(PlatformDetection), nameof(PlatformDetection.IsBrowser), nameof(PlatformDetection.IsCoreCLR))]
     [Fact]
     public static void TestEntryPoint()
     {

diff --git a/src/tests/readytorun/DynamicMethodGCStress/DynamicMethodGCStress.csproj b/src/tests/readytorun/DynamicMethodGCStress/DynamicMethodGCStress.csproj
@@ -8,8 +8,7 @@
     <UnloadabilityIncompatible>true</UnloadabilityIncompatible>
 
     <!-- This is an explicit crossgen test -->
-    <AlwaysUseCrossGen2 Condition="'$(RuntimeFlavor)' != 'coreclr' or '$(TargetOS)' != 'browser'">true</AlwaysUseCrossGen2>
-    <CrossGenTest Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">false</CrossGenTest>
+    <AlwaysUseCrossGen2>true</AlwaysUseCrossGen2>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="$(MSBuildProjectName).cs" />

diff --git a/src/tests/readytorun/GenericCycleDetection/Breadth1Test.cs b/src/tests/readytorun/GenericCycleDetection/Breadth1Test.cs
@@ -192,9 +192,8 @@ public static int Construct(int seed)
             };
         }
     }
-    
+
     [ActiveIssue("These tests are not supposed to be run with mono.", TestRuntimes.Mono)]
-    [ActiveIssue("https://github.com/dotnet/runtime/issues/131767", typeof(PlatformDetection), nameof(PlatformDetection.IsBrowser), nameof(PlatformDetection.IsCoreCLR))]
     [Fact]
     public static void BreadthTest()
     {

diff --git a/src/tests/readytorun/GenericCycleDetection/Breadth1Test.csproj b/src/tests/readytorun/GenericCycleDetection/Breadth1Test.csproj
@@ -4,8 +4,7 @@
     <RequiresProcessIsolation>true</RequiresProcessIsolation>
     <CLRTestTargetUnsupported Condition="'$(RuntimeFlavor)' != 'coreclr'">true</CLRTestTargetUnsupported>
     <!-- This is an explicit crossgen test -->
-    <AlwaysUseCrossGen2 Condition="'$(RuntimeFlavor)' != 'coreclr' or '$(TargetOS)' != 'browser'">true</AlwaysUseCrossGen2>
-    <CrossGenTest Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">false</CrossGenTest>
+    <AlwaysUseCrossGen2>true</AlwaysUseCrossGen2>
     <!-- Without this flag Crossgen2 crashes after several minutes with arithmetic overflow -->
     <CrossGen2TestExtraArguments>--maxgenericcycle:1 --maxgenericcyclebreadth:1</CrossGen2TestExtraArguments>
   </PropertyGroup>

diff --git a/src/tests/readytorun/GenericCycleDetection/Depth1Test.cs b/src/tests/readytorun/GenericCycleDetection/Depth1Test.cs
@@ -33,9 +33,8 @@ private struct Oper2<T> {}
     private struct Oper3<T> {}
     private struct Oper4<T> {}
     private struct Oper5<T> {}
-    
+
     [ActiveIssue("These tests are not supposed to be run with mono.", TestRuntimes.Mono)]
-    [ActiveIssue("https://github.com/dotnet/runtime/issues/131767", typeof(PlatformDetection), nameof(PlatformDetection.IsBrowser), nameof(PlatformDetection.IsCoreCLR))]
     [Fact]
     public static void BreadthTest()
     {

diff --git a/src/tests/readytorun/GenericCycleDetection/Depth1Test.csproj b/src/tests/readytorun/GenericCycleDetection/Depth1Test.csproj
@@ -4,8 +4,7 @@
     <RequiresProcessIsolation>true</RequiresProcessIsolation>
     <CLRTestTargetUnsupported Condition="'$(RuntimeFlavor)' != 'coreclr'">true</CLRTestTargetUnsupported>
     <!-- This is an explicit crossgen test -->
-    <AlwaysUseCrossGen2 Condition="'$(RuntimeFlavor)' != 'coreclr' or '$(TargetOS)' != 'browser'">true</AlwaysUseCrossGen2>
-    <CrossGenTest Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">false</CrossGenTest>
+    <AlwaysUseCrossGen2>true</AlwaysUseCrossGen2>
     <!-- Without this flag Crossgen2 crashes after several minutes with arithmetic overflow -->
     <CrossGen2TestExtraArguments>--maxgenericcycle:1 --maxgenericcyclebreadth:-1</CrossGen2TestExtraArguments>
   </PropertyGroup>

diff --git a/src/tests/readytorun/fieldlayout/fieldlayout.csproj b/src/tests/readytorun/fieldlayout/fieldlayout.csproj
@@ -4,8 +4,7 @@
     <!-- Needed for IlasmRoundTripIncompatible -->
     <RequiresProcessIsolation>true</RequiresProcessIsolation>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <AlwaysUseCrossGen2 Condition="'$(RuntimeFlavor)' != 'coreclr' or '$(TargetOS)' != 'browser'">true</AlwaysUseCrossGen2>
-    <CrossGenTest Condition="'$(RuntimeFlavor)' == 'coreclr' and '$(TargetOS)' == 'browser'">false</CrossGenTest>
+    <AlwaysUseCrossGen2>true</AlwaysUseCrossGen2>
     <IlasmRoundTripIncompatible>true</IlasmRoundTripIncompatible>
   </PropertyGroup>
   <ItemGroup>

diff --git a/src/tests/readytorun/fieldlayout/fieldlayouttests.cs b/src/tests/readytorun/fieldlayout/fieldlayouttests.cs
@@ -9,7 +9,6 @@ public class Test
     // This is done by touching the various types, and then relying on the verification logic in R2R images to detect failures.
     [ActiveIssue("These tests are not supposed to be run with mono.", TestRuntimes.Mono)]
     [ActiveIssue("https://github.com/dotnet/runtime/pull/131421", typeof(PlatformDetection), nameof(PlatformDetection.IsBrowser), nameof(PlatformDetection.IsCoreCLR))]
-    [ActiveIssue("https://github.com/dotnet/runtime/issues/131767", typeof(PlatformDetection), nameof(PlatformDetection.IsBrowser), nameof(PlatformDetection.IsCoreCLR))]
     [Fact]
     public static void TestEntryPoint()
     {
-Original file line number
+Diff line change
@@ Expand Up / @@ -192,9 +192,8 @@ public static int Construct(int seed) @@
                 };
             }
         }
         [ActiveIssue("These tests are not supposed to be run with mono.", TestRuntimes.Mono)]
-        [ActiveIssue("https://github.com/dotnet/runtime/issues/131767", typeof(PlatformDetection), nameof(PlatformDetection.IsBrowser), nameof(PlatformDetection.IsCoreCLR))]
         [Fact]
         public static void BreadthTest()
         {
@@ Expand Down @@