Fix RequiresDynamicCode warnings in OleDb (#118624)

This specifically addresses IL3050 warnings (ones generated as part of
AOT-compat). Contributes to #75480

Author: agocke

src/libraries/System.Data.OleDb/ref/System.Data.OleDb.cs

@@ -8,6 +8,9 @@ namespace System.Data.OleDb
 {
     [System.ComponentModel.DesignerAttribute("Microsoft.VSDesigner.Data.VS.OleDbCommandDesigner, Microsoft.VSDesigner, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
     [System.ComponentModel.ToolboxItemAttribute(true)]
+#if NET
+    [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
     public sealed partial class OleDbCommand : System.Data.Common.DbCommand, System.Data.IDbCommand, System.ICloneable, System.IDisposable
     {
         public OleDbCommand() { }
@@ -81,6 +84,9 @@ protected override void SetRowUpdatingHandler(System.Data.Common.DbDataAdapter a
         public string UnquoteIdentifier(string quotedIdentifier, System.Data.OleDb.OleDbConnection? connection) { throw null; }
     }
     [System.ComponentModel.DefaultEventAttribute("InfoMessage")]
+#if NET
+    [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
     public sealed partial class OleDbConnection : System.Data.Common.DbConnection, System.Data.IDbConnection, System.ICloneable, System.IDisposable
     {
         public OleDbConnection() { }
@@ -127,6 +133,9 @@ public void ResetState() { }
     }
     [System.ComponentModel.DefaultPropertyAttribute("Provider")]
     [System.ComponentModel.RefreshPropertiesAttribute(System.ComponentModel.RefreshProperties.All)]
+#if NET
+    [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
     public sealed partial class OleDbConnectionStringBuilder : System.Data.Common.DbConnectionStringBuilder
     {
         public OleDbConnectionStringBuilder() { }
@@ -151,6 +160,9 @@ public override void Clear() { }
     }
     [System.ComponentModel.DesignerAttribute("Microsoft.VSDesigner.Data.VS.OleDbDataAdapterDesigner, Microsoft.VSDesigner, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
     [System.ComponentModel.ToolboxItemAttribute("Microsoft.VSDesigner.Data.VS.OleDbDataAdapterToolboxItem, Microsoft.VSDesigner, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
+#if NET
+    [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
     public sealed partial class OleDbDataAdapter : System.Data.Common.DbDataAdapter, System.Data.IDataAdapter, System.Data.IDbDataAdapter, System.ICloneable
     {
         public OleDbDataAdapter() { }
@@ -183,6 +195,9 @@ protected override void OnRowUpdated(System.Data.Common.RowUpdatedEventArgs valu
         protected override void OnRowUpdating(System.Data.Common.RowUpdatingEventArgs value) { }
         object System.ICloneable.Clone() { throw null; }
     }
+#if NET
+    [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
     public sealed partial class OleDbDataReader : System.Data.Common.DbDataReader
     {
         internal OleDbDataReader() { }
@@ -229,8 +244,17 @@ public override void Close() { }
     public sealed partial class OleDbEnumerator
     {
         public OleDbEnumerator() { }
+#if NET
+        [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
         public System.Data.DataTable GetElements() { throw null; }
+#if NET
+        [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
         public static System.Data.OleDb.OleDbDataReader GetEnumerator(System.Type type) { throw null; }
+#if NET
+        [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
         public static System.Data.OleDb.OleDbDataReader GetRootEnumerator() { throw null; }
     }
     public sealed partial class OleDbError
@@ -265,6 +289,9 @@ internal OleDbException() { }
 #endif
         public override void GetObjectData(System.Runtime.Serialization.SerializationInfo si, System.Runtime.Serialization.StreamingContext context) { }
     }
+#if NET
+    [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
     public sealed partial class OleDbFactory : System.Data.Common.DbProviderFactory
     {
         internal OleDbFactory() { }
@@ -477,6 +504,9 @@ public sealed partial class OleDbSchemaGuid
         public static readonly System.Guid View_Table_Usage;
         public OleDbSchemaGuid() { }
     }
+#if NET
+    [System.Diagnostics.CodeAnalysis.RequiresDynamicCode("OleDbConnection is not AOT-compatible.")]
+#endif
     public sealed partial class OleDbTransaction : System.Data.Common.DbTransaction
     {
         internal OleDbTransaction() { }

src/libraries/System.Data.OleDb/src/OleDbCommand.cs

@@ -14,6 +14,7 @@ namespace System.Data.OleDb
 {
     [Designer("Microsoft.VSDesigner.Data.VS.OleDbCommandDesigner, Microsoft.VSDesigner, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
     [ToolboxItem(true)]
+    [RequiresDynamicCode(OleDbConnection.TrimWarning)]
     public sealed class OleDbCommand : DbCommand, ICloneable, IDbCommand
     {
         // command data

src/libraries/System.Data.OleDb/src/OleDbConnection.cs

@@ -19,8 +19,11 @@ namespace System.Data.OleDb
     //    it won't happen if you directly create the provider and set its properties
     // 2. First call on IDBInitialize must be Initialize, can't QI for any other interfaces before that
     [DefaultEvent("InfoMessage")]
+    [RequiresDynamicCode(OleDbConnection.TrimWarning)]
     public sealed partial class OleDbConnection : DbConnection, ICloneable, IDbConnection
     {
+        internal const string TrimWarning = "OleDbConnection is not AOT-compatible.";
+
         private static readonly object EventInfoMessage = new object();
 
         public OleDbConnection(string? connectionString) : this()

src/libraries/System.Data.OleDb/src/OleDbConnectionFactory.cs

@@ -6,11 +6,13 @@
 using System.Data.Common;
 using System.Data.ProviderBase;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Runtime.Versioning;
 
 namespace System.Data.OleDb
 {
+    [RequiresDynamicCode("XML deserialization requires dynamic code")]
     internal sealed class OleDbConnectionFactory : DbConnectionFactory
     {
         private OleDbConnectionFactory() : base() { }

src/libraries/System.Data.OleDb/src/OleDbConnectionInternal.cs

@@ -5,13 +5,17 @@
 using System.Data.Common;
 using System.Data.ProviderBase;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
 using System.Runtime.InteropServices;
 using System.Threading;
 using SysTx = System.Transactions;
 
 namespace System.Data.OleDb
 {
+#if NET
+    [RequiresDynamicCode(OleDbConnection.TrimWarning)]
+#endif
     internal sealed class OleDbConnectionInternal : DbConnectionInternal, IDisposable
     {
         private static volatile OleDbServicesWrapper? idataInitialize;
@@ -414,7 +418,11 @@ internal void EnlistTransactionInternal(SysTx.Transaction? transaction)
                         tagDBLITERALINFO tag = new tagDBLITERALINFO();
                         for (int i = 0; i < literalCount; ++i, offset += ODB.SizeOf_tagDBLITERALINFO)
                         {
-                            Marshal.PtrToStructure((nint)offset, tag);
+                            if (offset is null)
+                            {
+                                throw new NullReferenceException();
+                            }
+                            tag = Marshal.PtrToStructure<tagDBLITERALINFO>((IntPtr)offset)!;
 
                             DataRow row = table.NewRow();
                             row[literalName] = ((OleDbLiteral)tag.it).ToString();
@@ -591,7 +599,7 @@ internal DataTable BuildSchemaGuids()
                         for (int i = 0, offset = 0; i < supportedSchemas.Length; ++i, offset += ODB.SizeOf_Guid)
                         {
                             IntPtr ptr = ADP.IntPtrOffset(schemaGuids, i * ODB.SizeOf_Guid);
-                            supportedSchemas[i]._schemaRowset = (Guid)Marshal.PtrToStructure(ptr, typeof(Guid))!;
+                            supportedSchemas[i]._schemaRowset = Marshal.PtrToStructure<Guid>(ptr)!;
                         }
                     }
                     if (IntPtr.Zero != schemaRestrictions)

src/libraries/System.Data.OleDb/src/OleDbConnectionStringBuilder.cs

@@ -15,6 +15,9 @@ namespace System.Data.OleDb
     [DefaultProperty("Provider")]
     [RefreshProperties(RefreshProperties.All)]
     [TypeConverter(typeof(OleDbConnectionStringBuilder.OleDbConnectionStringBuilderConverter))]
+#if NET
+    [RequiresDynamicCode(OleDbConnection.TrimWarning)]
+#endif
     public sealed class OleDbConnectionStringBuilder : DbConnectionStringBuilder
     {
         private enum Keywords
@@ -528,6 +531,7 @@ private Dictionary<string, OleDbPropertyInfo> GetProviderInfo(string provider)
             return providerInfo;
         }
 
+        [RequiresDynamicCode(OleDbConnection.TrimWarning)]
         private sealed class OleDbProviderConverter : StringConverter
         {
             private const int DBSOURCETYPE_DATASOURCE_TDP = 1;
@@ -599,6 +603,7 @@ internal enum OleDbServiceValues : int
             Default = ~(ClientCursor | AggregationAfterSession),
         };
 
+        [RequiresDynamicCode(OleDbConnection.TrimWarning)]
         internal sealed class OleDbServicesConverter : TypeConverter
         {
             private StandardValuesCollection? _standardValues;

src/libraries/System.Data.OleDb/src/OleDbDataAdapter.cs

@@ -4,12 +4,14 @@
 using System.ComponentModel;
 using System.Data.Common;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.Runtime.InteropServices;
 
 namespace System.Data.OleDb
 {
     [Designer("Microsoft.VSDesigner.Data.VS.OleDbDataAdapterDesigner, Microsoft.VSDesigner, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
     [ToolboxItem("Microsoft.VSDesigner.Data.VS.OleDbDataAdapterToolboxItem, Microsoft.VSDesigner, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
+    [RequiresDynamicCode(OleDbConnection.TrimWarning)]
     public sealed class OleDbDataAdapter : DbDataAdapter, IDbDataAdapter, ICloneable
     {
         private static readonly object EventRowUpdated = new object();

src/libraries/System.Data.OleDb/src/OleDbDataReader.cs

@@ -14,6 +14,7 @@
 
 namespace System.Data.OleDb
 {
+    [RequiresDynamicCode(OleDbConnection.TrimWarning)]
     public sealed class OleDbDataReader : DbDataReader
     {
         private readonly CommandBehavior _commandBehavior;

src/libraries/System.Data.OleDb/src/OleDbEnumerator.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Data.Common;
+using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
 
 namespace System.Data.OleDb
@@ -12,6 +13,9 @@ public OleDbEnumerator()
         {
         }
 
+#if NET
+        [RequiresDynamicCode(OleDbConnection.TrimWarning)]
+#endif
         public DataTable GetElements()
         {
             DataTable dataTable = new DataTable("MSDAENUM");
@@ -21,17 +25,26 @@ public DataTable GetElements()
             return dataTable;
         }
 
+#if NET
+        [RequiresDynamicCode(OleDbConnection.TrimWarning)]
+#endif
         public static OleDbDataReader GetEnumerator(Type type)
         {
             return GetEnumeratorFromType(type);
         }
 
+#if NET
+        [RequiresDynamicCode(OleDbConnection.TrimWarning)]
+#endif
         internal static OleDbDataReader GetEnumeratorFromType(Type type)
         {
             object? value = Activator.CreateInstance(type, System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance, null, null, CultureInfo.InvariantCulture, null);
             return GetEnumeratorReader(value);
         }
 
+#if NET
+        [RequiresDynamicCode(OleDbConnection.TrimWarning)]
+#endif
         private static OleDbDataReader GetEnumeratorReader(object? value)
         {
             NativeMethods.ISourcesRowset? srcrowset;
@@ -66,6 +79,9 @@ private static OleDbDataReader GetEnumeratorReader(object? value)
             return dataReader;
         }
 
+#if NET
+        [RequiresDynamicCode(OleDbConnection.TrimWarning)]
+#endif
         public static OleDbDataReader GetRootEnumerator()
         {
             //readonly Guid CLSID_MSDAENUM = new Guid(0xc8b522d0,0x5cf3,0x11ce,0xad,0xe5,0x00,0xaa,0x00,0x44,0x77,0x3d);

src/libraries/System.Data.OleDb/src/OleDbFactory.cs

@@ -2,9 +2,11 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Data.Common;
+using System.Diagnostics.CodeAnalysis;
 
 namespace System.Data.OleDb
 {
+    [RequiresDynamicCode(OleDbConnection.TrimWarning)]
     public sealed class OleDbFactory : DbProviderFactory
     {
         public static readonly OleDbFactory Instance = new OleDbFactory();