diff --git a/src/coreclr/inc/clrconfigvalues.h b/src/coreclr/inc/clrconfigvalues.h
index 542510f79b4a74..3c2a9c3dab3dd8 100644
--- a/src/coreclr/inc/clrconfigvalues.h
+++ b/src/coreclr/inc/clrconfigvalues.h
@@ -720,7 +720,7 @@ RETAIL_CONFIG_DWORD_INFO(EXTERNAL_EnableRiscV64Zbb,             W("EnableRiscV64
 #endif
 
 // Runtime-async
-RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_RuntimeAsync, W("RuntimeAsync"), 0, "Enables runtime async method support")
+RETAIL_CONFIG_DWORD_INFO(UNSUPPORTED_RuntimeAsync, W("RuntimeAsync"), 1, "Enables runtime async method support")
 
 ///
 /// Uncategorized
diff --git a/src/coreclr/nativeaot/Runtime/Crst.h b/src/coreclr/nativeaot/Runtime/Crst.h
index 13e2177afb77bd..28491ab7ef1f30 100644
--- a/src/coreclr/nativeaot/Runtime/Crst.h
+++ b/src/coreclr/nativeaot/Runtime/Crst.h
@@ -5,7 +5,7 @@
 // -----------------------------------------------------------------------------------------------------------
 //
 // Minimal Crst implementation. Doesn't support much except for the basic locking
-// functionality (in particular there is no rank violation checking).
+// functionality (in particular there is no rank violation checking)...
 //
 
 #ifndef __Crst_h__
diff --git a/src/coreclr/vm/array.h b/src/coreclr/vm/array.h
index 1f687f140eef3b..3f9df733dcc904 100644
--- a/src/coreclr/vm/array.h
+++ b/src/coreclr/vm/array.h
@@ -8,7 +8,7 @@
 // A 32 dimension array with at least 2 elements in each dimension requires
 // 4gb of memory. Limit the maximum number of dimensions to a value that 
 // requires 4gb of memory.
-// If you make this bigger, you need to make MAX_CLASSNAME_LENGTH bigger too.
+// If you make this bigger, you need to make MAX_CLASSNAME_LENGTH bigger too..
 #define MAX_RANK 32
 
 class MethodTable;
diff --git a/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs b/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs
index 1f3020782e754b..c0e896bb5c0e9f 100644
--- a/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs
@@ -134,7 +134,7 @@ public class Task : IAsyncResult, IDisposable
         [Flags]
         internal enum TaskStateFlags
         {
-            // State constants for m_stateFlags;
+            // State constants for m_stateFlags:
             // The bits of m_stateFlags are allocated as follows:
             //   0x7FFF0000 - Task state flags
             //   0x0000FF00 - internal TaskCreationOptions flags
diff --git a/src/tests/async/Directory.Build.props b/src/tests/async/Directory.Build.props
index a1f7d48cf60a7d..f505092384b1b1 100644
--- a/src/tests/async/Directory.Build.props
+++ b/src/tests/async/Directory.Build.props
@@ -5,7 +5,7 @@
 
   <PropertyGroup>
     <RunAnalyzers>true</RunAnalyzers>
-    <NoWarn>$(NoWarn);xUnit1013;CS1998</NoWarn>
+    <NoWarn>$(NoWarn);xUnit1013;CS1998;SYSLIB5007</NoWarn>
     <EnableNETAnalyzers>false</EnableNETAnalyzers>
     <Features>$(Features);runtime-async=on</Features>
   </PropertyGroup>
diff --git a/src/tests/async/Directory.Build.targets b/src/tests/async/Directory.Build.targets
index 5a4d413a9e1f62..61a1b2822ed114 100644
--- a/src/tests/async/Directory.Build.targets
+++ b/src/tests/async/Directory.Build.targets
@@ -4,10 +4,5 @@
     <DisableProjectBuild Condition="'$(RuntimeFlavor)' == 'mono' or '$(TestBuildMode)' == 'nativeaot' or '$(TargetArchitecture)' == 'wasm'">true</DisableProjectBuild>
   </PropertyGroup>
 
-  <PropertyGroup>
-    <!-- runtime async testing in main repo NYI -->
-    <DisableProjectBuild>true</DisableProjectBuild>
-  </PropertyGroup>
-
   <Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.targets, $(MSBuildThisFileDirectory)..))" />
 </Project>
diff --git a/src/tests/async/struct/struct.cs b/src/tests/async/struct/struct.cs
index 7c5062d499cb42..32116fe3cec777 100644
--- a/src/tests/async/struct/struct.cs
+++ b/src/tests/async/struct/struct.cs
@@ -45,6 +45,8 @@ private struct S
 
         public S(int value) => Value = value;
 
+        // Roslyn NYI - async in structs. Remove opt-out once supported.
+        [System.Runtime.CompilerServices.RuntimeAsyncMethodGeneration(false)]
         public async Task Test()
         {
             // TODO: C# compiler is expected to do this, but not in the prototype.
@@ -59,6 +61,8 @@ public async Task Test()
             AssertEqual(102, @this.Value);
         }
 
+        // Roslyn NYI - async in structs. Remove opt-out once supported.
+        [System.Runtime.CompilerServices.RuntimeAsyncMethodGeneration(false)]
         private async Task InstanceCall()
         {
             // TODO: C# compiler is expected to do this, but not in the prototype.