[mono][wasm] Respect [Un]SupportedOSPlatform in the Mono pinvoke generator

src/mono/wasm/Wasm.Build.Tests/PInvokeTableGeneratorTests.cs

@@ -422,6 +422,23 @@ public async Task EnsureWasmAbiRulesAreFollowedInAOT(Configuration config, bool
         public async Task EnsureWasmAbiRulesAreFollowedInInterpreter(Configuration config, bool aot) =>
             await EnsureWasmAbiRulesAreFollowed(config, aot);
 
+        [Theory]
+        [BuildAndRun(aot: false)]
+        [TestCategory("native-mono")]
+        public void UnsupportedOSPlatformPInvokeIsSkipped(Configuration config, bool aot)
+        {
+            // https://github.com/dotnet/runtime/issues/110870: a Windows-only pinvoke with
+            // non-blittable parameters must be skipped (not analyzed) when building for the
+            // browser, so it must not emit WASM0060/WASM0062/WASM0001.
+            ProjectInfo info = CopyTestAsset(config, aot, TestAsset.WasmBasicTestApp, "osplatform_pinvoke",
+                extraProperties: "<WasmBuildNative>true</WasmBuildNative>");
+            ReplaceFile(Path.Combine("Common", "Program.cs"), Path.Combine(BuildEnvironment.TestAssetsPath, "EntryPoints", "PInvoke", "UnsupportedOSPlatform.cs"));
+            (_, string output) = BuildProject(info, config, new BuildOptions(AssertAppBundle: false, AOT: aot), isNativeBuild: true);
+            Assert.DoesNotContain("WASM0001", output);
+            Assert.DoesNotContain("WASM0060", output);
+            Assert.DoesNotContain("WASM0062", output);
+        }
+
         [Theory]
         [BuildAndRun(aot: true, config: Configuration.Release)]
         [TestCategory("native-mono")]

src/mono/wasm/build/WasmApp.Common.targets

@@ -792,6 +792,7 @@
       PInvokeOutputPath="$(_WasmPInvokeTablePath)"
       InterpToNativeOutputPath="$(_WasmInterpToNativeTablePath)"
       CacheFilePath="$(_WasmM2NCachePath)"
+      TargetOS="$(TargetOS)"
       IsLibraryMode="$(_IsLibraryMode)">
       <Output TaskParameter="FileWrites" ItemName="FileWrites" />
     </ManagedToNativeGenerator>

src/mono/wasm/testassets/EntryPoints/PInvoke/UnsupportedOSPlatform.cs

@@ -0,0 +1,34 @@
+using System;
+using System.Runtime.InteropServices;
+using System.Runtime.Versioning;
+
+public class Test
+{
+    public static int Main(string[] argv)
+    {
+        Console.WriteLine("TestOutput -> Main running");
+        return 42;
+    }
+}
+
+// Regression coverage for https://github.com/dotnet/runtime/issues/110870:
+// a Windows-only P/Invoke with non-blittable parameters must be skipped by the wasm
+// pinvoke collector when building for the browser, and must not emit WASM0060/WASM0062/WASM0001.
+[SupportedOSPlatform("windows")]
+internal static class Win32Interop
+{
+    [DllImport("gdi32.dll")]
+    public static extern int GetCharABCWidthsFloat(HandleRef hdc, uint iFirst, uint iLast, [Out] ABCFLOAT[] lpABCF);
+
+    [DllImport("user32.dll")]
+    public static extern int MethodWithNonBlittableObject(object arg, HandleRef handle);
+}
+
+internal struct ABCFLOAT
+{
+#pragma warning disable CS0649 // fields are only used to describe the native struct layout
+    public float abcfA;
+    public float abcfB;
+    public float abcfC;
+#pragma warning restore CS0649
+}

src/tasks/WasmAppBuilder/mono/ManagedToNativeGenerator.cs

@@ -34,6 +34,10 @@ public class ManagedToNativeGenerator : Task
 
     public bool IsLibraryMode { get; set; }
 
+    public string TargetOS { get; set; } = "browser";
+
+    private static readonly string[] s_knownTargetOSes = new[] { "browser", "wasi" };
+
     [Output]
     public string[]? FileWrites { get; private set; }
 
@@ -51,6 +55,19 @@ public override bool Execute()
             return false;
         }
 
+        if (string.IsNullOrWhiteSpace(TargetOS))
+        {
+            Log.LogError($"{nameof(ManagedToNativeGenerator)}.{nameof(TargetOS)} cannot be empty; expected one of: {string.Join(", ", s_knownTargetOSes)}");
+            return false;
+        }
+
+        TargetOS = TargetOS.Trim().ToLowerInvariant();
+        if (Array.IndexOf(s_knownTargetOSes, TargetOS) < 0)
+        {
+            Log.LogError($"{nameof(ManagedToNativeGenerator)}.{nameof(TargetOS)} '{TargetOS}' is not recognized; expected one of: {string.Join(", ", s_knownTargetOSes)}");
+            return false;
+        }
+
         try
         {
             var logAdapter = new LogAdapter(Log);
@@ -70,7 +87,7 @@ private void ExecuteInternal(LogAdapter log)
         List<string> managedAssemblies = FilterOutUnmanagedBinaries(Assemblies);
         if (ShouldRun(managedAssemblies))
         {
-            var pinvoke = new PInvokeTableGenerator(FixupSymbolName, log, IsLibraryMode);
+            var pinvoke = new PInvokeTableGenerator(FixupSymbolName, log, IsLibraryMode, TargetOS);
             var icall = new IcallTableGenerator(RuntimeIcallTableFile, FixupSymbolName, log, isCoreClr: false);
 
             var resolver = new PathAssemblyResolver(managedAssemblies);

src/tasks/WasmAppBuilder/mono/PInvokeCollector.cs

@@ -60,11 +60,15 @@ public int GetHashCode(PInvoke pinvoke)
 
 internal sealed class PInvokeCollector {
     private readonly Dictionary<Assembly, bool> _assemblyDisableRuntimeMarshallingAttributeCache = new();
+    private readonly Dictionary<Type, bool> _typeUnsupportedOnPlatformCache = new();
+    private readonly Dictionary<Assembly, bool> _assemblyUnsupportedOnPlatformCache = new();
+    private readonly string _targetOS;
     private LogAdapter Log { get; init; }
 
-    public PInvokeCollector(LogAdapter log)
+    public PInvokeCollector(LogAdapter log, string targetOS)
     {
         Log = log;
+        _targetOS = targetOS;
     }
 
     public void CollectPInvokes(List<PInvoke> pinvokes, List<PInvokeCallback> callbacks, HashSet<string> signatures, Type type)
@@ -102,6 +106,9 @@ void CollectPInvokesForMethod(MethodInfo method)
         {
             if ((method.Attributes & MethodAttributes.PinvokeImpl) != 0)
             {
+                if (IsUnsupportedOnPlatform(method))
+                    return;
+
                 var dllimport = method.CustomAttributes.First(attr => attr.AttributeType.Name == "DllImportAttribute");
                 var wasmLinkage = method.CustomAttributes.Any(attr => attr.AttributeType.Name == "WasmImportLinkageAttribute");
                 var module = (string)dllimport.ConstructorArguments[0].Value!;
@@ -124,6 +131,9 @@ bool DoesMethodHaveCallbacks(MethodInfo method, LogAdapter log)
             if (!MethodHasCallbackAttributes(method))
                 return false;
 
+            if (IsUnsupportedOnPlatform(method))
+                return false;
+
             if (TryIsMethodGetParametersUnsupported(method, out string? reason))
             {
                 Log.Warning("WASM0001", $"Skipping callback '{method.DeclaringType!.FullName}::{method.Name}' because '{reason}'.");
@@ -207,6 +217,102 @@ private bool HasAssemblyDisableRuntimeMarshallingAttribute(Assembly assembly)
 
         return value;
     }
+
+    private bool IsUnsupportedOnPlatform(MethodInfo method)
+    {
+        PlatformSupport methodResult = EvaluatePlatformAttributes(CustomAttributeData.GetCustomAttributes(method));
+        if (methodResult == PlatformSupport.Unsupported)
+            return true;
+        if (methodResult == PlatformSupport.Supported)
+            return false;
+
+        return IsUnsupportedOnPlatform(method.DeclaringType);
+    }
+
+    private bool IsUnsupportedOnPlatform(Type? type)
+    {
+        if (type is null)
+            return false;
+
+        if (_typeUnsupportedOnPlatformCache.TryGetValue(type, out bool cached))
+            return cached;
+
+        bool value;
+        PlatformSupport typeResult = EvaluatePlatformAttributes(CustomAttributeData.GetCustomAttributes(type));
+        if (typeResult == PlatformSupport.Unsupported)
+        {
+            value = true;
+        }
+        else if (typeResult == PlatformSupport.Supported)
+        {
+            value = false;
+        }
+        else if (type.DeclaringType is not null)
+        {
+            value = IsUnsupportedOnPlatform(type.DeclaringType);
+        }
+        else
+        {
+            value = IsAssemblyUnsupportedOnPlatform(type.Assembly);
+        }
+
+        _typeUnsupportedOnPlatformCache[type] = value;
+        return value;
+    }
+
+    private bool IsAssemblyUnsupportedOnPlatform(Assembly assembly)
+    {
+        if (!_assemblyUnsupportedOnPlatformCache.TryGetValue(assembly, out bool value))
+        {
+            PlatformSupport asmResult = EvaluatePlatformAttributes(assembly.GetCustomAttributesData());
+            value = asmResult == PlatformSupport.Unsupported;
+            _assemblyUnsupportedOnPlatformCache[assembly] = value;
+        }
+
+        return value;
+    }
+
+    private enum PlatformSupport
+    {
+        Unknown,     // No platform attributes were observed at this scope
+        Supported,   // Explicitly supported here (target appears in a SupportedOSPlatform list)
+        Unsupported, // Explicitly unsupported here (target matches UnsupportedOSPlatform, or
+                     // SupportedOSPlatform is present and does not list the target)
+    }
+
+    private PlatformSupport EvaluatePlatformAttributes(IList<CustomAttributeData> attrs)
+    {
+        bool hasSupportedOSPlatform = false;
+        bool hasSupportedTarget = false;
+        foreach (CustomAttributeData cattr in attrs)
+        {
+            try
+            {
+                if (cattr.AttributeType.FullName == "System.Runtime.Versioning.UnsupportedOSPlatformAttribute" &&
+                    cattr.ConstructorArguments.Count > 0 &&
+                    cattr.ConstructorArguments[0].Value?.ToString() == _targetOS)
+                {
+                    return PlatformSupport.Unsupported;
+                }
+                if (cattr.AttributeType.FullName == "System.Runtime.Versioning.SupportedOSPlatformAttribute" &&
+                    cattr.ConstructorArguments.Count > 0)
+                {
+                    hasSupportedOSPlatform = true;
+                    if (cattr.ConstructorArguments[0].Value?.ToString() == _targetOS)
+                        hasSupportedTarget = true;
+                }
+            }
+            catch
+            {
+                // Assembly not found, ignore
+            }
+        }
+
+        if (hasSupportedOSPlatform)
+            return hasSupportedTarget ? PlatformSupport.Supported : PlatformSupport.Unsupported;
+
+        return PlatformSupport.Unknown;
+    }
 }
 
 internal sealed class PInvokeCallbackComparer : IComparer<PInvokeCallback>

src/tasks/WasmAppBuilder/mono/PInvokeTableGenerator.cs

@@ -28,11 +28,11 @@ internal sealed class PInvokeTableGenerator
     private readonly PInvokeCollector _pinvokeCollector;
     private readonly bool _isLibraryMode;
 
-    public PInvokeTableGenerator(Func<string, string> fixupSymbolName, LogAdapter log, bool isLibraryMode = false)
+    public PInvokeTableGenerator(Func<string, string> fixupSymbolName, LogAdapter log, bool isLibraryMode, string targetOS)
     {
         Log = log;
         _fixupSymbolName = fixupSymbolName;
-        _pinvokeCollector = new(log);
+        _pinvokeCollector = new(log, targetOS);
         _isLibraryMode = isLibraryMode;
     }