Remove the usage of attributes for field/method discovery.

Instead, introduce GeneratedCodeInfo which passes in what we need, and adjust the codegen to take account of this.

22 files changed, 243 insertions, 405 deletions

diff --git a/csharp/src/Google.Protobuf/Google.Protobuf.csproj b/csharp/src/Google.Protobuf/Google.Protobuf.csproj
index 50756299..29320ca8 100644
--- a/csharp/src/Google.Protobuf/Google.Protobuf.csproj
+++ b/csharp/src/Google.Protobuf/Google.Protobuf.csproj
@@ -81,6 +81,7 @@
     <Compile Include="Reflection\FieldDescriptor.cs" />

     <Compile Include="Reflection\FieldType.cs" />

     <Compile Include="Reflection\FileDescriptor.cs" />

+    <Compile Include="Reflection\GeneratedCodeInfo.cs" />

     <Compile Include="Reflection\IDescriptor.cs" />

     <Compile Include="Reflection\IFieldAccessor.cs" />

     <Compile Include="Reflection\MapFieldAccessor.cs" />

@@ -90,8 +91,6 @@
     <Compile Include="Reflection\OneofDescriptor.cs" />

     <Compile Include="Reflection\PackageDescriptor.cs" />

     <Compile Include="Reflection\PartialClasses.cs" />

-    <Compile Include="Reflection\ProtobufOneofAttribute.cs" />

-    <Compile Include="Reflection\ProtobufFieldAttribute.cs" />

     <Compile Include="Reflection\ReflectionUtil.cs" />

     <Compile Include="Reflection\RepeatedFieldAccessor.cs" />

     <Compile Include="Reflection\ServiceDescriptor.cs" />

diff --git a/csharp/src/Google.Protobuf/Reflection/DescriptorProtoFile.cs b/csharp/src/Google.Protobuf/Reflection/DescriptorProtoFile.cs
index 6565982c..def70b53 100644
--- a/csharp/src/Google.Protobuf/Reflection/DescriptorProtoFile.cs
+++ b/csharp/src/Google.Protobuf/Reflection/DescriptorProtoFile.cs
@@ -131,10 +131,30 @@ namespace Google.Protobuf.Reflection {
             "YWlsaW5nX2NvbW1lbnRzGAQgASgJEiEKGWxlYWRpbmdfZGV0YWNoZWRfY29t", 
             "bWVudHMYBiADKAlCWAoTY29tLmdvb2dsZS5wcm90b2J1ZkIQRGVzY3JpcHRv", 
             "clByb3Rvc0gBWgpkZXNjcmlwdG9yogIDR1BCqgIaR29vZ2xlLlByb3RvYnVm", 
-          "LlJlZmxlY3Rpb24="));
+            "LlJlZmxlY3Rpb24="));
       descriptor = pbr::FileDescriptor.InternalBuildGeneratedFileFrom(descriptorData,
           new pbr::FileDescriptor[] { },
-          new global::System.Type[] { typeof(global::Google.Protobuf.Reflection.FileDescriptorSet), typeof(global::Google.Protobuf.Reflection.FileDescriptorProto), typeof(global::Google.Protobuf.Reflection.DescriptorProto), typeof(global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange), typeof(global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange), typeof(global::Google.Protobuf.Reflection.FieldDescriptorProto), typeof(global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Type), typeof(global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Label), typeof(global::Google.Protobuf.Reflection.OneofDescriptorProto), typeof(global::Google.Protobuf.Reflection.EnumDescriptorProto), typeof(global::Google.Protobuf.Reflection.EnumValueDescriptorProto), typeof(global::Google.Protobuf.Reflection.ServiceDescriptorProto), typeof(global::Google.Protobuf.Reflection.MethodDescriptorProto), typeof(global::Google.Protobuf.Reflection.FileOptions), typeof(global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode), typeof(global::Google.Protobuf.Reflection.MessageOptions), typeof(global::Google.Protobuf.Reflection.FieldOptions), typeof(global::Google.Protobuf.Reflection.FieldOptions.Types.CType), typeof(global::Google.Protobuf.Reflection.FieldOptions.Types.JSType), typeof(global::Google.Protobuf.Reflection.EnumOptions), typeof(global::Google.Protobuf.Reflection.EnumValueOptions), typeof(global::Google.Protobuf.Reflection.ServiceOptions), typeof(global::Google.Protobuf.Reflection.MethodOptions), typeof(global::Google.Protobuf.Reflection.UninterpretedOption), typeof(global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart), typeof(global::Google.Protobuf.Reflection.SourceCodeInfo), typeof(global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location), });
+          new pbr::GeneratedCodeInfo(null, new pbr::GeneratedCodeInfo[] {
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.FileDescriptorSet), new[]{ "File" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.FileDescriptorProto), new[]{ "Name", "Package", "Dependency", "PublicDependency", "WeakDependency", "MessageType", "EnumType", "Service", "Extension", "Options", "SourceCodeInfo", "Syntax" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.DescriptorProto), new[]{ "Name", "Field", "Extension", "NestedType", "EnumType", "ExtensionRange", "OneofDecl", "Options", "ReservedRange", "ReservedName" }, null, null, new pbr::GeneratedCodeInfo[] { new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange), new[]{ "Start", "End" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange), new[]{ "Start", "End" }, null, null, null)}),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.FieldDescriptorProto), new[]{ "Name", "Number", "Label", "Type", "TypeName", "Extendee", "DefaultValue", "OneofIndex", "Options" }, null, new[]{ typeof(global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Type), typeof(global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Label) }, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.OneofDescriptorProto), new[]{ "Name" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.EnumDescriptorProto), new[]{ "Name", "Value", "Options" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.EnumValueDescriptorProto), new[]{ "Name", "Number", "Options" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.ServiceDescriptorProto), new[]{ "Name", "Method", "Options" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.MethodDescriptorProto), new[]{ "Name", "InputType", "OutputType", "Options", "ClientStreaming", "ServerStreaming" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.FileOptions), new[]{ "JavaPackage", "JavaOuterClassname", "JavaMultipleFiles", "JavaGenerateEqualsAndHash", "JavaStringCheckUtf8", "OptimizeFor", "GoPackage", "CcGenericServices", "JavaGenericServices", "PyGenericServices", "Deprecated", "CcEnableArenas", "ObjcClassPrefix", "CsharpNamespace", "UninterpretedOption" }, null, new[]{ typeof(global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode) }, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.MessageOptions), new[]{ "MessageSetWireFormat", "NoStandardDescriptorAccessor", "Deprecated", "MapEntry", "UninterpretedOption" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.FieldOptions), new[]{ "Ctype", "Packed", "Jstype", "Lazy", "Deprecated", "Weak", "UninterpretedOption" }, null, new[]{ typeof(global::Google.Protobuf.Reflection.FieldOptions.Types.CType), typeof(global::Google.Protobuf.Reflection.FieldOptions.Types.JSType) }, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.EnumOptions), new[]{ "AllowAlias", "Deprecated", "UninterpretedOption" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.EnumValueOptions), new[]{ "Deprecated", "UninterpretedOption" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.ServiceOptions), new[]{ "Deprecated", "UninterpretedOption" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.MethodOptions), new[]{ "Deprecated", "UninterpretedOption" }, null, null, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.UninterpretedOption), new[]{ "Name", "IdentifierValue", "PositiveIntValue", "NegativeIntValue", "DoubleValue", "StringValue", "AggregateValue" }, null, null, new pbr::GeneratedCodeInfo[] { new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart), new[]{ "NamePart_", "IsExtension" }, null, null, null)}),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.SourceCodeInfo), new[]{ "Location" }, null, null, new pbr::GeneratedCodeInfo[] { new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location), new[]{ "Path", "Span", "LeadingComments", "TrailingComments", "LeadingDetachedComments" }, null, null, null)})
+          }));
     }
     #endregion
 
@@ -145,8 +165,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<FileDescriptorSet> _parser = new pb::MessageParser<FileDescriptorSet>(() => new FileDescriptorSet());
     public static pb::MessageParser<FileDescriptorSet> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "file" };
-    private static readonly uint[] _fieldTags = new uint[] { 10 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[0]; }
     }
@@ -184,7 +202,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.FileDescriptorProto> _repeated_file_codec
         = pb::FieldCodec.ForMessage(10, global::Google.Protobuf.Reflection.FileDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.FileDescriptorProto> file_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.FileDescriptorProto>();
-    [pbr::ProtobufField(1, "file")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.FileDescriptorProto> File {
       get { return file_; }
     }
@@ -257,8 +274,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<FileDescriptorProto> _parser = new pb::MessageParser<FileDescriptorProto>(() => new FileDescriptorProto());
     public static pb::MessageParser<FileDescriptorProto> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "dependency", "enum_type", "extension", "message_type", "name", "options", "package", "public_dependency", "service", "source_code_info", "syntax", "weak_dependency" };
-    private static readonly uint[] _fieldTags = new uint[] { 26, 42, 58, 34, 10, 66, 18, 80, 50, 74, 98, 88 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[1]; }
     }
@@ -313,7 +328,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    [pbr::ProtobufField(1, "name")]
     internal string Name {
       get { return name_; }
       set {
@@ -324,7 +338,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int PackageFieldNumber = 2;
     private string package_ = "";
-    [pbr::ProtobufField(2, "package")]
     internal string Package {
       get { return package_; }
       set {
@@ -337,7 +350,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<string> _repeated_dependency_codec
         = pb::FieldCodec.ForString(26);
     private readonly pbc::RepeatedField<string> dependency_ = new pbc::RepeatedField<string>();
-    [pbr::ProtobufField(3, "dependency")]
     internal pbc::RepeatedField<string> Dependency {
       get { return dependency_; }
     }
@@ -346,7 +358,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<int> _repeated_publicDependency_codec
         = pb::FieldCodec.ForInt32(80);
     private readonly pbc::RepeatedField<int> publicDependency_ = new pbc::RepeatedField<int>();
-    [pbr::ProtobufField(10, "public_dependency")]
     internal pbc::RepeatedField<int> PublicDependency {
       get { return publicDependency_; }
     }
@@ -355,7 +366,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<int> _repeated_weakDependency_codec
         = pb::FieldCodec.ForInt32(88);
     private readonly pbc::RepeatedField<int> weakDependency_ = new pbc::RepeatedField<int>();
-    [pbr::ProtobufField(11, "weak_dependency")]
     internal pbc::RepeatedField<int> WeakDependency {
       get { return weakDependency_; }
     }
@@ -364,7 +374,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.DescriptorProto> _repeated_messageType_codec
         = pb::FieldCodec.ForMessage(34, global::Google.Protobuf.Reflection.DescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> messageType_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto>();
-    [pbr::ProtobufField(4, "message_type")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> MessageType {
       get { return messageType_; }
     }
@@ -373,7 +382,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.EnumDescriptorProto> _repeated_enumType_codec
         = pb::FieldCodec.ForMessage(42, global::Google.Protobuf.Reflection.EnumDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> enumType_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto>();
-    [pbr::ProtobufField(5, "enum_type")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> EnumType {
       get { return enumType_; }
     }
@@ -382,7 +390,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.ServiceDescriptorProto> _repeated_service_codec
         = pb::FieldCodec.ForMessage(50, global::Google.Protobuf.Reflection.ServiceDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.ServiceDescriptorProto> service_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.ServiceDescriptorProto>();
-    [pbr::ProtobufField(6, "service")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.ServiceDescriptorProto> Service {
       get { return service_; }
     }
@@ -391,14 +398,12 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.FieldDescriptorProto> _repeated_extension_codec
         = pb::FieldCodec.ForMessage(58, global::Google.Protobuf.Reflection.FieldDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> extension_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto>();
-    [pbr::ProtobufField(7, "extension")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> Extension {
       get { return extension_; }
     }
 
     public const int OptionsFieldNumber = 8;
     private global::Google.Protobuf.Reflection.FileOptions options_;
-    [pbr::ProtobufField(8, "options")]
     internal global::Google.Protobuf.Reflection.FileOptions Options {
       get { return options_; }
       set {
@@ -409,7 +414,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int SourceCodeInfoFieldNumber = 9;
     private global::Google.Protobuf.Reflection.SourceCodeInfo sourceCodeInfo_;
-    [pbr::ProtobufField(9, "source_code_info")]
     internal global::Google.Protobuf.Reflection.SourceCodeInfo SourceCodeInfo {
       get { return sourceCodeInfo_; }
       set {
@@ -420,7 +424,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int SyntaxFieldNumber = 12;
     private string syntax_ = "";
-    [pbr::ProtobufField(12, "syntax")]
     internal string Syntax {
       get { return syntax_; }
       set {
@@ -645,8 +648,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<DescriptorProto> _parser = new pb::MessageParser<DescriptorProto>(() => new DescriptorProto());
     public static pb::MessageParser<DescriptorProto> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "enum_type", "extension", "extension_range", "field", "name", "nested_type", "oneof_decl", "options", "reserved_name", "reserved_range" };
-    private static readonly uint[] _fieldTags = new uint[] { 34, 50, 42, 18, 10, 26, 66, 58, 82, 74 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[2]; }
     }
@@ -699,7 +700,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    [pbr::ProtobufField(1, "name")]
     internal string Name {
       get { return name_; }
       set {
@@ -712,7 +712,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.FieldDescriptorProto> _repeated_field_codec
         = pb::FieldCodec.ForMessage(18, global::Google.Protobuf.Reflection.FieldDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> field_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto>();
-    [pbr::ProtobufField(2, "field")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> Field {
       get { return field_; }
     }
@@ -721,7 +720,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.FieldDescriptorProto> _repeated_extension_codec
         = pb::FieldCodec.ForMessage(50, global::Google.Protobuf.Reflection.FieldDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> extension_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto>();
-    [pbr::ProtobufField(6, "extension")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> Extension {
       get { return extension_; }
     }
@@ -730,7 +728,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.DescriptorProto> _repeated_nestedType_codec
         = pb::FieldCodec.ForMessage(26, global::Google.Protobuf.Reflection.DescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> nestedType_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto>();
-    [pbr::ProtobufField(3, "nested_type")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> NestedType {
       get { return nestedType_; }
     }
@@ -739,7 +736,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.EnumDescriptorProto> _repeated_enumType_codec
         = pb::FieldCodec.ForMessage(34, global::Google.Protobuf.Reflection.EnumDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> enumType_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto>();
-    [pbr::ProtobufField(4, "enum_type")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> EnumType {
       get { return enumType_; }
     }
@@ -748,7 +744,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange> _repeated_extensionRange_codec
         = pb::FieldCodec.ForMessage(42, global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange> extensionRange_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange>();
-    [pbr::ProtobufField(5, "extension_range")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange> ExtensionRange {
       get { return extensionRange_; }
     }
@@ -757,14 +752,12 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.OneofDescriptorProto> _repeated_oneofDecl_codec
         = pb::FieldCodec.ForMessage(66, global::Google.Protobuf.Reflection.OneofDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.OneofDescriptorProto> oneofDecl_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.OneofDescriptorProto>();
-    [pbr::ProtobufField(8, "oneof_decl")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.OneofDescriptorProto> OneofDecl {
       get { return oneofDecl_; }
     }
 
     public const int OptionsFieldNumber = 7;
     private global::Google.Protobuf.Reflection.MessageOptions options_;
-    [pbr::ProtobufField(7, "options")]
     internal global::Google.Protobuf.Reflection.MessageOptions Options {
       get { return options_; }
       set {
@@ -777,7 +770,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange> _repeated_reservedRange_codec
         = pb::FieldCodec.ForMessage(74, global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange> reservedRange_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange>();
-    [pbr::ProtobufField(9, "reserved_range")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange> ReservedRange {
       get { return reservedRange_; }
     }
@@ -786,7 +778,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<string> _repeated_reservedName_codec
         = pb::FieldCodec.ForString(82);
     private readonly pbc::RepeatedField<string> reservedName_ = new pbc::RepeatedField<string>();
-    [pbr::ProtobufField(10, "reserved_name")]
     internal pbc::RepeatedField<string> ReservedName {
       get { return reservedName_; }
     }
@@ -961,8 +952,6 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::MessageParser<ExtensionRange> _parser = new pb::MessageParser<ExtensionRange>(() => new ExtensionRange());
         public static pb::MessageParser<ExtensionRange> Parser { get { return _parser; } }
 
-        private static readonly string[] _fieldNames = new string[] { "end", "start" };
-        private static readonly uint[] _fieldTags = new uint[] { 16, 8 };
         public static pbr::MessageDescriptor Descriptor {
           get { return global::Google.Protobuf.Reflection.DescriptorProto.Descriptor.NestedTypes[0]; }
         }
@@ -998,7 +987,6 @@ namespace Google.Protobuf.Reflection {
 
         public const int StartFieldNumber = 1;
         private int start_;
-        [pbr::ProtobufField(1, "start")]
         internal int Start {
           get { return start_; }
           set {
@@ -1009,7 +997,6 @@ namespace Google.Protobuf.Reflection {
 
         public const int EndFieldNumber = 2;
         private int end_;
-        [pbr::ProtobufField(2, "end")]
         internal int End {
           get { return end_; }
           set {
@@ -1109,8 +1096,6 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::MessageParser<ReservedRange> _parser = new pb::MessageParser<ReservedRange>(() => new ReservedRange());
         public static pb::MessageParser<ReservedRange> Parser { get { return _parser; } }
 
-        private static readonly string[] _fieldNames = new string[] { "end", "start" };
-        private static readonly uint[] _fieldTags = new uint[] { 16, 8 };
         public static pbr::MessageDescriptor Descriptor {
           get { return global::Google.Protobuf.Reflection.DescriptorProto.Descriptor.NestedTypes[1]; }
         }
@@ -1146,7 +1131,6 @@ namespace Google.Protobuf.Reflection {
 
         public const int StartFieldNumber = 1;
         private int start_;
-        [pbr::ProtobufField(1, "start")]
         internal int Start {
           get { return start_; }
           set {
@@ -1157,7 +1141,6 @@ namespace Google.Protobuf.Reflection {
 
         public const int EndFieldNumber = 2;
         private int end_;
-        [pbr::ProtobufField(2, "end")]
         internal int End {
           get { return end_; }
           set {
@@ -1262,8 +1245,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<FieldDescriptorProto> _parser = new pb::MessageParser<FieldDescriptorProto>(() => new FieldDescriptorProto());
     public static pb::MessageParser<FieldDescriptorProto> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "default_value", "extendee", "label", "name", "number", "oneof_index", "options", "type", "type_name" };
-    private static readonly uint[] _fieldTags = new uint[] { 58, 18, 32, 10, 24, 72, 66, 40, 50 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[3]; }
     }
@@ -1307,7 +1288,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    [pbr::ProtobufField(1, "name")]
     internal string Name {
       get { return name_; }
       set {
@@ -1318,7 +1298,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NumberFieldNumber = 3;
     private int number_;
-    [pbr::ProtobufField(3, "number")]
     internal int Number {
       get { return number_; }
       set {
@@ -1329,7 +1308,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int LabelFieldNumber = 4;
     private global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Label label_ = global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Label.LABEL_OPTIONAL;
-    [pbr::ProtobufField(4, "label")]
     internal global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Label Label {
       get { return label_; }
       set {
@@ -1340,7 +1318,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int TypeFieldNumber = 5;
     private global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Type type_ = global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Type.TYPE_DOUBLE;
-    [pbr::ProtobufField(5, "type")]
     internal global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Type Type {
       get { return type_; }
       set {
@@ -1351,7 +1328,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int TypeNameFieldNumber = 6;
     private string typeName_ = "";
-    [pbr::ProtobufField(6, "type_name")]
     internal string TypeName {
       get { return typeName_; }
       set {
@@ -1362,7 +1338,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int ExtendeeFieldNumber = 2;
     private string extendee_ = "";
-    [pbr::ProtobufField(2, "extendee")]
     internal string Extendee {
       get { return extendee_; }
       set {
@@ -1373,7 +1348,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int DefaultValueFieldNumber = 7;
     private string defaultValue_ = "";
-    [pbr::ProtobufField(7, "default_value")]
     internal string DefaultValue {
       get { return defaultValue_; }
       set {
@@ -1384,7 +1358,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int OneofIndexFieldNumber = 9;
     private int oneofIndex_;
-    [pbr::ProtobufField(9, "oneof_index")]
     internal int OneofIndex {
       get { return oneofIndex_; }
       set {
@@ -1395,7 +1368,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int OptionsFieldNumber = 8;
     private global::Google.Protobuf.Reflection.FieldOptions options_;
-    [pbr::ProtobufField(8, "options")]
     internal global::Google.Protobuf.Reflection.FieldOptions Options {
       get { return options_; }
       set {
@@ -1646,8 +1618,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<OneofDescriptorProto> _parser = new pb::MessageParser<OneofDescriptorProto>(() => new OneofDescriptorProto());
     public static pb::MessageParser<OneofDescriptorProto> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "name" };
-    private static readonly uint[] _fieldTags = new uint[] { 10 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[4]; }
     }
@@ -1682,7 +1652,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    [pbr::ProtobufField(1, "name")]
     internal string Name {
       get { return name_; }
       set {
@@ -1766,8 +1735,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<EnumDescriptorProto> _parser = new pb::MessageParser<EnumDescriptorProto>(() => new EnumDescriptorProto());
     public static pb::MessageParser<EnumDescriptorProto> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "name", "options", "value" };
-    private static readonly uint[] _fieldTags = new uint[] { 10, 26, 18 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[5]; }
     }
@@ -1806,7 +1773,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    [pbr::ProtobufField(1, "name")]
     internal string Name {
       get { return name_; }
       set {
@@ -1819,14 +1785,12 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.EnumValueDescriptorProto> _repeated_value_codec
         = pb::FieldCodec.ForMessage(18, global::Google.Protobuf.Reflection.EnumValueDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumValueDescriptorProto> value_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumValueDescriptorProto>();
-    [pbr::ProtobufField(2, "value")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumValueDescriptorProto> Value {
       get { return value_; }
     }
 
     public const int OptionsFieldNumber = 3;
     private global::Google.Protobuf.Reflection.EnumOptions options_;
-    [pbr::ProtobufField(3, "options")]
     internal global::Google.Protobuf.Reflection.EnumOptions Options {
       get { return options_; }
       set {
@@ -1941,8 +1905,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<EnumValueDescriptorProto> _parser = new pb::MessageParser<EnumValueDescriptorProto>(() => new EnumValueDescriptorProto());
     public static pb::MessageParser<EnumValueDescriptorProto> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "name", "number", "options" };
-    private static readonly uint[] _fieldTags = new uint[] { 10, 16, 26 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[6]; }
     }
@@ -1980,7 +1942,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    [pbr::ProtobufField(1, "name")]
     internal string Name {
       get { return name_; }
       set {
@@ -1991,7 +1952,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NumberFieldNumber = 2;
     private int number_;
-    [pbr::ProtobufField(2, "number")]
     internal int Number {
       get { return number_; }
       set {
@@ -2002,7 +1962,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int OptionsFieldNumber = 3;
     private global::Google.Protobuf.Reflection.EnumValueOptions options_;
-    [pbr::ProtobufField(3, "options")]
     internal global::Google.Protobuf.Reflection.EnumValueOptions Options {
       get { return options_; }
       set {
@@ -2124,8 +2083,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<ServiceDescriptorProto> _parser = new pb::MessageParser<ServiceDescriptorProto>(() => new ServiceDescriptorProto());
     public static pb::MessageParser<ServiceDescriptorProto> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "method", "name", "options" };
-    private static readonly uint[] _fieldTags = new uint[] { 18, 10, 26 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[7]; }
     }
@@ -2164,7 +2121,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    [pbr::ProtobufField(1, "name")]
     internal string Name {
       get { return name_; }
       set {
@@ -2177,14 +2133,12 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.MethodDescriptorProto> _repeated_method_codec
         = pb::FieldCodec.ForMessage(18, global::Google.Protobuf.Reflection.MethodDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.MethodDescriptorProto> method_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.MethodDescriptorProto>();
-    [pbr::ProtobufField(2, "method")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.MethodDescriptorProto> Method {
       get { return method_; }
     }
 
     public const int OptionsFieldNumber = 3;
     private global::Google.Protobuf.Reflection.ServiceOptions options_;
-    [pbr::ProtobufField(3, "options")]
     internal global::Google.Protobuf.Reflection.ServiceOptions Options {
       get { return options_; }
       set {
@@ -2299,8 +2253,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<MethodDescriptorProto> _parser = new pb::MessageParser<MethodDescriptorProto>(() => new MethodDescriptorProto());
     public static pb::MessageParser<MethodDescriptorProto> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "client_streaming", "input_type", "name", "options", "output_type", "server_streaming" };
-    private static readonly uint[] _fieldTags = new uint[] { 40, 18, 10, 34, 26, 48 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[8]; }
     }
@@ -2341,7 +2293,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    [pbr::ProtobufField(1, "name")]
     internal string Name {
       get { return name_; }
       set {
@@ -2352,7 +2303,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int InputTypeFieldNumber = 2;
     private string inputType_ = "";
-    [pbr::ProtobufField(2, "input_type")]
     internal string InputType {
       get { return inputType_; }
       set {
@@ -2363,7 +2313,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int OutputTypeFieldNumber = 3;
     private string outputType_ = "";
-    [pbr::ProtobufField(3, "output_type")]
     internal string OutputType {
       get { return outputType_; }
       set {
@@ -2374,7 +2323,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int OptionsFieldNumber = 4;
     private global::Google.Protobuf.Reflection.MethodOptions options_;
-    [pbr::ProtobufField(4, "options")]
     internal global::Google.Protobuf.Reflection.MethodOptions Options {
       get { return options_; }
       set {
@@ -2385,7 +2333,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int ClientStreamingFieldNumber = 5;
     private bool clientStreaming_;
-    [pbr::ProtobufField(5, "client_streaming")]
     internal bool ClientStreaming {
       get { return clientStreaming_; }
       set {
@@ -2396,7 +2343,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int ServerStreamingFieldNumber = 6;
     private bool serverStreaming_;
-    [pbr::ProtobufField(6, "server_streaming")]
     internal bool ServerStreaming {
       get { return serverStreaming_; }
       set {
@@ -2566,8 +2512,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<FileOptions> _parser = new pb::MessageParser<FileOptions>(() => new FileOptions());
     public static pb::MessageParser<FileOptions> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "cc_enable_arenas", "cc_generic_services", "csharp_namespace", "deprecated", "go_package", "java_generate_equals_and_hash", "java_generic_services", "java_multiple_files", "java_outer_classname", "java_package", "java_string_check_utf8", "objc_class_prefix", "optimize_for", "py_generic_services", "uninterpreted_option" };
-    private static readonly uint[] _fieldTags = new uint[] { 248, 128, 298, 184, 90, 160, 136, 80, 66, 10, 216, 290, 72, 144, 7994 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[9]; }
     }
@@ -2617,7 +2561,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaPackageFieldNumber = 1;
     private string javaPackage_ = "";
-    [pbr::ProtobufField(1, "java_package")]
     internal string JavaPackage {
       get { return javaPackage_; }
       set {
@@ -2628,7 +2571,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaOuterClassnameFieldNumber = 8;
     private string javaOuterClassname_ = "";
-    [pbr::ProtobufField(8, "java_outer_classname")]
     internal string JavaOuterClassname {
       get { return javaOuterClassname_; }
       set {
@@ -2639,7 +2581,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaMultipleFilesFieldNumber = 10;
     private bool javaMultipleFiles_;
-    [pbr::ProtobufField(10, "java_multiple_files")]
     internal bool JavaMultipleFiles {
       get { return javaMultipleFiles_; }
       set {
@@ -2650,7 +2591,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaGenerateEqualsAndHashFieldNumber = 20;
     private bool javaGenerateEqualsAndHash_;
-    [pbr::ProtobufField(20, "java_generate_equals_and_hash")]
     internal bool JavaGenerateEqualsAndHash {
       get { return javaGenerateEqualsAndHash_; }
       set {
@@ -2661,7 +2601,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaStringCheckUtf8FieldNumber = 27;
     private bool javaStringCheckUtf8_;
-    [pbr::ProtobufField(27, "java_string_check_utf8")]
     internal bool JavaStringCheckUtf8 {
       get { return javaStringCheckUtf8_; }
       set {
@@ -2672,7 +2611,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int OptimizeForFieldNumber = 9;
     private global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode optimizeFor_ = global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode.SPEED;
-    [pbr::ProtobufField(9, "optimize_for")]
     internal global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode OptimizeFor {
       get { return optimizeFor_; }
       set {
@@ -2683,7 +2621,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int GoPackageFieldNumber = 11;
     private string goPackage_ = "";
-    [pbr::ProtobufField(11, "go_package")]
     internal string GoPackage {
       get { return goPackage_; }
       set {
@@ -2694,7 +2631,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int CcGenericServicesFieldNumber = 16;
     private bool ccGenericServices_;
-    [pbr::ProtobufField(16, "cc_generic_services")]
     internal bool CcGenericServices {
       get { return ccGenericServices_; }
       set {
@@ -2705,7 +2641,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaGenericServicesFieldNumber = 17;
     private bool javaGenericServices_;
-    [pbr::ProtobufField(17, "java_generic_services")]
     internal bool JavaGenericServices {
       get { return javaGenericServices_; }
       set {
@@ -2716,7 +2651,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int PyGenericServicesFieldNumber = 18;
     private bool pyGenericServices_;
-    [pbr::ProtobufField(18, "py_generic_services")]
     internal bool PyGenericServices {
       get { return pyGenericServices_; }
       set {
@@ -2727,7 +2661,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 23;
     private bool deprecated_;
-    [pbr::ProtobufField(23, "deprecated")]
     internal bool Deprecated {
       get { return deprecated_; }
       set {
@@ -2738,7 +2671,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int CcEnableArenasFieldNumber = 31;
     private bool ccEnableArenas_;
-    [pbr::ProtobufField(31, "cc_enable_arenas")]
     internal bool CcEnableArenas {
       get { return ccEnableArenas_; }
       set {
@@ -2749,7 +2681,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int ObjcClassPrefixFieldNumber = 36;
     private string objcClassPrefix_ = "";
-    [pbr::ProtobufField(36, "objc_class_prefix")]
     internal string ObjcClassPrefix {
       get { return objcClassPrefix_; }
       set {
@@ -2760,7 +2691,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int CsharpNamespaceFieldNumber = 37;
     private string csharpNamespace_ = "";
-    [pbr::ProtobufField(37, "csharp_namespace")]
     internal string CsharpNamespace {
       get { return csharpNamespace_; }
       set {
@@ -2773,7 +2703,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    [pbr::ProtobufField(999, "uninterpreted_option")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
@@ -3082,8 +3011,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<MessageOptions> _parser = new pb::MessageParser<MessageOptions>(() => new MessageOptions());
     public static pb::MessageParser<MessageOptions> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "deprecated", "map_entry", "message_set_wire_format", "no_standard_descriptor_accessor", "uninterpreted_option" };
-    private static readonly uint[] _fieldTags = new uint[] { 24, 56, 8, 16, 7994 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[10]; }
     }
@@ -3123,7 +3050,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int MessageSetWireFormatFieldNumber = 1;
     private bool messageSetWireFormat_;
-    [pbr::ProtobufField(1, "message_set_wire_format")]
     internal bool MessageSetWireFormat {
       get { return messageSetWireFormat_; }
       set {
@@ -3134,7 +3060,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NoStandardDescriptorAccessorFieldNumber = 2;
     private bool noStandardDescriptorAccessor_;
-    [pbr::ProtobufField(2, "no_standard_descriptor_accessor")]
     internal bool NoStandardDescriptorAccessor {
       get { return noStandardDescriptorAccessor_; }
       set {
@@ -3145,7 +3070,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 3;
     private bool deprecated_;
-    [pbr::ProtobufField(3, "deprecated")]
     internal bool Deprecated {
       get { return deprecated_; }
       set {
@@ -3156,7 +3080,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int MapEntryFieldNumber = 7;
     private bool mapEntry_;
-    [pbr::ProtobufField(7, "map_entry")]
     internal bool MapEntry {
       get { return mapEntry_; }
       set {
@@ -3169,7 +3092,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    [pbr::ProtobufField(999, "uninterpreted_option")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
@@ -3306,8 +3228,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<FieldOptions> _parser = new pb::MessageParser<FieldOptions>(() => new FieldOptions());
     public static pb::MessageParser<FieldOptions> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "ctype", "deprecated", "jstype", "lazy", "packed", "uninterpreted_option", "weak" };
-    private static readonly uint[] _fieldTags = new uint[] { 8, 24, 48, 40, 16, 7994, 80 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[11]; }
     }
@@ -3349,7 +3269,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int CtypeFieldNumber = 1;
     private global::Google.Protobuf.Reflection.FieldOptions.Types.CType ctype_ = global::Google.Protobuf.Reflection.FieldOptions.Types.CType.STRING;
-    [pbr::ProtobufField(1, "ctype")]
     internal global::Google.Protobuf.Reflection.FieldOptions.Types.CType Ctype {
       get { return ctype_; }
       set {
@@ -3360,7 +3279,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int PackedFieldNumber = 2;
     private bool packed_;
-    [pbr::ProtobufField(2, "packed")]
     internal bool Packed {
       get { return packed_; }
       set {
@@ -3371,7 +3289,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int JstypeFieldNumber = 6;
     private global::Google.Protobuf.Reflection.FieldOptions.Types.JSType jstype_ = global::Google.Protobuf.Reflection.FieldOptions.Types.JSType.JS_NORMAL;
-    [pbr::ProtobufField(6, "jstype")]
     internal global::Google.Protobuf.Reflection.FieldOptions.Types.JSType Jstype {
       get { return jstype_; }
       set {
@@ -3382,7 +3299,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int LazyFieldNumber = 5;
     private bool lazy_;
-    [pbr::ProtobufField(5, "lazy")]
     internal bool Lazy {
       get { return lazy_; }
       set {
@@ -3393,7 +3309,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 3;
     private bool deprecated_;
-    [pbr::ProtobufField(3, "deprecated")]
     internal bool Deprecated {
       get { return deprecated_; }
       set {
@@ -3404,7 +3319,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int WeakFieldNumber = 10;
     private bool weak_;
-    [pbr::ProtobufField(10, "weak")]
     internal bool Weak {
       get { return weak_; }
       set {
@@ -3417,7 +3331,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    [pbr::ProtobufField(999, "uninterpreted_option")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
@@ -3604,8 +3517,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<EnumOptions> _parser = new pb::MessageParser<EnumOptions>(() => new EnumOptions());
     public static pb::MessageParser<EnumOptions> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "allow_alias", "deprecated", "uninterpreted_option" };
-    private static readonly uint[] _fieldTags = new uint[] { 16, 24, 7994 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[12]; }
     }
@@ -3643,7 +3554,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int AllowAliasFieldNumber = 2;
     private bool allowAlias_;
-    [pbr::ProtobufField(2, "allow_alias")]
     internal bool AllowAlias {
       get { return allowAlias_; }
       set {
@@ -3654,7 +3564,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 3;
     private bool deprecated_;
-    [pbr::ProtobufField(3, "deprecated")]
     internal bool Deprecated {
       get { return deprecated_; }
       set {
@@ -3667,7 +3576,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    [pbr::ProtobufField(999, "uninterpreted_option")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
@@ -3772,8 +3680,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<EnumValueOptions> _parser = new pb::MessageParser<EnumValueOptions>(() => new EnumValueOptions());
     public static pb::MessageParser<EnumValueOptions> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "deprecated", "uninterpreted_option" };
-    private static readonly uint[] _fieldTags = new uint[] { 8, 7994 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[13]; }
     }
@@ -3810,7 +3716,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 1;
     private bool deprecated_;
-    [pbr::ProtobufField(1, "deprecated")]
     internal bool Deprecated {
       get { return deprecated_; }
       set {
@@ -3823,7 +3728,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    [pbr::ProtobufField(999, "uninterpreted_option")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
@@ -3912,8 +3816,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<ServiceOptions> _parser = new pb::MessageParser<ServiceOptions>(() => new ServiceOptions());
     public static pb::MessageParser<ServiceOptions> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "deprecated", "uninterpreted_option" };
-    private static readonly uint[] _fieldTags = new uint[] { 264, 7994 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[14]; }
     }
@@ -3950,7 +3852,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 33;
     private bool deprecated_;
-    [pbr::ProtobufField(33, "deprecated")]
     internal bool Deprecated {
       get { return deprecated_; }
       set {
@@ -3963,7 +3864,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    [pbr::ProtobufField(999, "uninterpreted_option")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
@@ -4052,8 +3952,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<MethodOptions> _parser = new pb::MessageParser<MethodOptions>(() => new MethodOptions());
     public static pb::MessageParser<MethodOptions> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "deprecated", "uninterpreted_option" };
-    private static readonly uint[] _fieldTags = new uint[] { 264, 7994 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[15]; }
     }
@@ -4090,7 +3988,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 33;
     private bool deprecated_;
-    [pbr::ProtobufField(33, "deprecated")]
     internal bool Deprecated {
       get { return deprecated_; }
       set {
@@ -4103,7 +4000,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    [pbr::ProtobufField(999, "uninterpreted_option")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
@@ -4192,8 +4088,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<UninterpretedOption> _parser = new pb::MessageParser<UninterpretedOption>(() => new UninterpretedOption());
     public static pb::MessageParser<UninterpretedOption> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "aggregate_value", "double_value", "identifier_value", "name", "negative_int_value", "positive_int_value", "string_value" };
-    private static readonly uint[] _fieldTags = new uint[] { 66, 49, 26, 18, 40, 32, 58 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[16]; }
     }
@@ -4237,14 +4131,12 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart> _repeated_name_codec
         = pb::FieldCodec.ForMessage(18, global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart> name_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart>();
-    [pbr::ProtobufField(2, "name")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart> Name {
       get { return name_; }
     }
 
     public const int IdentifierValueFieldNumber = 3;
     private string identifierValue_ = "";
-    [pbr::ProtobufField(3, "identifier_value")]
     internal string IdentifierValue {
       get { return identifierValue_; }
       set {
@@ -4255,7 +4147,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int PositiveIntValueFieldNumber = 4;
     private ulong positiveIntValue_;
-    [pbr::ProtobufField(4, "positive_int_value")]
     internal ulong PositiveIntValue {
       get { return positiveIntValue_; }
       set {
@@ -4266,7 +4157,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int NegativeIntValueFieldNumber = 5;
     private long negativeIntValue_;
-    [pbr::ProtobufField(5, "negative_int_value")]
     internal long NegativeIntValue {
       get { return negativeIntValue_; }
       set {
@@ -4277,7 +4167,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int DoubleValueFieldNumber = 6;
     private double doubleValue_;
-    [pbr::ProtobufField(6, "double_value")]
     internal double DoubleValue {
       get { return doubleValue_; }
       set {
@@ -4288,7 +4177,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int StringValueFieldNumber = 7;
     private pb::ByteString stringValue_ = pb::ByteString.Empty;
-    [pbr::ProtobufField(7, "string_value")]
     internal pb::ByteString StringValue {
       get { return stringValue_; }
       set {
@@ -4299,7 +4187,6 @@ namespace Google.Protobuf.Reflection {
 
     public const int AggregateValueFieldNumber = 8;
     private string aggregateValue_ = "";
-    [pbr::ProtobufField(8, "aggregate_value")]
     internal string AggregateValue {
       get { return aggregateValue_; }
       set {
@@ -4473,8 +4360,6 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::MessageParser<NamePart> _parser = new pb::MessageParser<NamePart>(() => new NamePart());
         public static pb::MessageParser<NamePart> Parser { get { return _parser; } }
 
-        private static readonly string[] _fieldNames = new string[] { "is_extension", "name_part" };
-        private static readonly uint[] _fieldTags = new uint[] { 16, 10 };
         public static pbr::MessageDescriptor Descriptor {
           get { return global::Google.Protobuf.Reflection.UninterpretedOption.Descriptor.NestedTypes[0]; }
         }
@@ -4510,7 +4395,6 @@ namespace Google.Protobuf.Reflection {
 
         public const int NamePart_FieldNumber = 1;
         private string namePart_ = "";
-        [pbr::ProtobufField(1, "name_part")]
         internal string NamePart_ {
           get { return namePart_; }
           set {
@@ -4521,7 +4405,6 @@ namespace Google.Protobuf.Reflection {
 
         public const int IsExtensionFieldNumber = 2;
         private bool isExtension_;
-        [pbr::ProtobufField(2, "is_extension")]
         internal bool IsExtension {
           get { return isExtension_; }
           set {
@@ -4626,8 +4509,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::MessageParser<SourceCodeInfo> _parser = new pb::MessageParser<SourceCodeInfo>(() => new SourceCodeInfo());
     public static pb::MessageParser<SourceCodeInfo> Parser { get { return _parser; } }
 
-    private static readonly string[] _fieldNames = new string[] { "location" };
-    private static readonly uint[] _fieldTags = new uint[] { 10 };
     public static pbr::MessageDescriptor Descriptor {
       get { return global::Google.Protobuf.Reflection.DescriptorProtoFile.Descriptor.MessageTypes[17]; }
     }
@@ -4665,7 +4546,6 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location> _repeated_location_codec
         = pb::FieldCodec.ForMessage(10, global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location> location_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location>();
-    [pbr::ProtobufField(1, "location")]
     internal pbc::RepeatedField<global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location> Location {
       get { return location_; }
     }
@@ -4739,8 +4619,6 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::MessageParser<Location> _parser = new pb::MessageParser<Location>(() => new Location());
         public static pb::MessageParser<Location> Parser { get { return _parser; } }
 
-        private static readonly string[] _fieldNames = new string[] { "leading_comments", "leading_detached_comments", "path", "span", "trailing_comments" };
-        private static readonly uint[] _fieldTags = new uint[] { 26, 50, 10, 18, 34 };
         public static pbr::MessageDescriptor Descriptor {
           get { return global::Google.Protobuf.Reflection.SourceCodeInfo.Descriptor.NestedTypes[0]; }
         }
@@ -4784,7 +4662,6 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::FieldCodec<int> _repeated_path_codec
             = pb::FieldCodec.ForInt32(10);
         private readonly pbc::RepeatedField<int> path_ = new pbc::RepeatedField<int>();
-        [pbr::ProtobufField(1, "path")]
         internal pbc::RepeatedField<int> Path {
           get { return path_; }
         }
@@ -4793,14 +4670,12 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::FieldCodec<int> _repeated_span_codec
             = pb::FieldCodec.ForInt32(18);
         private readonly pbc::RepeatedField<int> span_ = new pbc::RepeatedField<int>();
-        [pbr::ProtobufField(2, "span")]
         internal pbc::RepeatedField<int> Span {
           get { return span_; }
         }
 
         public const int LeadingCommentsFieldNumber = 3;
         private string leadingComments_ = "";
-        [pbr::ProtobufField(3, "leading_comments")]
         internal string LeadingComments {
           get { return leadingComments_; }
           set {
@@ -4811,7 +4686,6 @@ namespace Google.Protobuf.Reflection {
 
         public const int TrailingCommentsFieldNumber = 4;
         private string trailingComments_ = "";
-        [pbr::ProtobufField(4, "trailing_comments")]
         internal string TrailingComments {
           get { return trailingComments_; }
           set {
@@ -4824,7 +4698,6 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::FieldCodec<string> _repeated_leadingDetachedComments_codec
             = pb::FieldCodec.ForString(50);
         private readonly pbc::RepeatedField<string> leadingDetachedComments_ = new pbc::RepeatedField<string>();
-        [pbr::ProtobufField(6, "leading_detached_comments")]
         internal pbc::RepeatedField<string> LeadingDetachedComments {
           get { return leadingDetachedComments_; }
         }
diff --git a/csharp/src/Google.Protobuf/Reflection/FieldDescriptor.cs b/csharp/src/Google.Protobuf/Reflection/FieldDescriptor.cs
index 57378e4c..a8609b8a 100644
--- a/csharp/src/Google.Protobuf/Reflection/FieldDescriptor.cs
+++ b/csharp/src/Google.Protobuf/Reflection/FieldDescriptor.cs
@@ -46,10 +46,11 @@ namespace Google.Protobuf.Reflection
         private readonly MessageDescriptor containingType;
         private readonly OneofDescriptor containingOneof;
         private FieldType fieldType;
+        private readonly string propertyName; // Annoyingly, needed in Crosslink.
         private IFieldAccessor accessor;
 
         internal FieldDescriptor(FieldDescriptorProto proto, FileDescriptor file,
-                                 MessageDescriptor parent, int index)
+                                 MessageDescriptor parent, int index, string propertyName)
             : base(file, file.ComputeFullName(parent, proto.Name), index)
         {
             this.proto = proto;
@@ -76,6 +77,12 @@ namespace Google.Protobuf.Reflection
             }
 
             file.DescriptorPool.AddSymbol(this);
+            // We can't create the accessor until we've cross-linked, unfortunately, as we
+            // may not know whether the type of the field is a map or not. Remember the property name
+            // for later.
+            // We could trust the generated code and check whether the type of the property is
+            // a MapField, but that feels a tad nasty.
+            this.propertyName = propertyName;
         }
 
         /// <summary>
@@ -291,26 +298,19 @@ namespace Google.Protobuf.Reflection
             {
                 throw new DescriptorValidationException(this, "MessageSet format is not supported.");
             }
-
-            accessor = CreateAccessor();
+            accessor = CreateAccessor(propertyName);
         }
 
-        private IFieldAccessor CreateAccessor()
+        private IFieldAccessor CreateAccessor(string propertyName)
         {
-            // TODO: Check the performance of this with some large protos. Each message is O(N^2) in the number of fields,
-            // which isn't great...
-            if (containingType.GeneratedType == null)
+            if (containingType.GeneratedType == null || propertyName == null)
             {
                 return null;
             }
-            var property = containingType
-                .GeneratedType
-                .GetProperties()
-                .FirstOrDefault(p => p.IsDefined(typeof(ProtobufFieldAttribute), false) &&
-                                     p.GetCustomAttributes(typeof(ProtobufFieldAttribute), false).Cast<ProtobufFieldAttribute>().Single().Number == FieldNumber);
+            var property = containingType.GeneratedType.GetProperty(propertyName);
             if (property == null)
             {
-                return null;
+                throw new DescriptorValidationException(this, "Property " + propertyName + " not found in " + containingType.GeneratedType);
             }
             return IsMap ? new MapFieldAccessor(property, this)
                 : IsRepeated ? new RepeatedFieldAccessor(property, this)
diff --git a/csharp/src/Google.Protobuf/Reflection/FileDescriptor.cs b/csharp/src/Google.Protobuf/Reflection/FileDescriptor.cs
index ba832b89..041d4711 100644
--- a/csharp/src/Google.Protobuf/Reflection/FileDescriptor.cs
+++ b/csharp/src/Google.Protobuf/Reflection/FileDescriptor.cs
@@ -62,12 +62,11 @@ namespace Google.Protobuf.Reflection
             get { return proto.Syntax == "proto3" ? ProtoSyntax.Proto3 : ProtoSyntax.Proto2; }
         }
 
-        private FileDescriptor(FileDescriptorProto proto, FileDescriptor[] dependencies, DescriptorPool pool, bool allowUnknownDependencies, Type[] generatedTypes)
+        private FileDescriptor(FileDescriptorProto proto, FileDescriptor[] dependencies, DescriptorPool pool, bool allowUnknownDependencies, GeneratedCodeInfo generatedCodeInfo)
         {
             this.pool = pool;
             this.proto = proto;
             this.dependencies = new ReadOnlyCollection<FileDescriptor>((FileDescriptor[]) dependencies.Clone());
-            IEnumerator<Type> generatedTypeIterator = generatedTypes == null ? null : ((IEnumerable<Type>)generatedTypes).GetEnumerator();
 
             publicDependencies = DeterminePublicDependencies(this, proto, dependencies, allowUnknownDependencies);
 
@@ -75,21 +74,15 @@ namespace Google.Protobuf.Reflection
 
             messageTypes = DescriptorUtil.ConvertAndMakeReadOnly(proto.MessageType,
                                                                  (message, index) =>
-                                                                 new MessageDescriptor(message, this, null, index, generatedTypeIterator));
+                                                                 new MessageDescriptor(message, this, null, index, generatedCodeInfo == null ? null : generatedCodeInfo.NestedTypes[index]));
 
             enumTypes = DescriptorUtil.ConvertAndMakeReadOnly(proto.EnumType,
                                                               (enumType, index) =>
-                                                              new EnumDescriptor(enumType, this, null, index, ReflectionUtil.GetNextType(generatedTypeIterator)));
+                                                              new EnumDescriptor(enumType, this, null, index, generatedCodeInfo == null ? null : generatedCodeInfo.NestedEnums[index]));
 
             services = DescriptorUtil.ConvertAndMakeReadOnly(proto.Service,
                                                              (service, index) =>
                                                              new ServiceDescriptor(service, this, index));
-
-            // We should now have consumed all the generated types.
-            if (generatedTypeIterator != null && generatedTypeIterator.MoveNext())
-            {
-                throw new ArgumentException("More generated types left over after consuming all expected ones", "generatedTypes");
-            }
         }
 
         /// <summary>
@@ -260,7 +253,7 @@ namespace Google.Protobuf.Reflection
             }
             return null;
         }
-        
+
         /// <summary>
         /// Builds a FileDescriptor from its protocol buffer representation.
         /// </summary>
@@ -269,10 +262,11 @@ namespace Google.Protobuf.Reflection
         /// file's dependencies, in the exact order listed in the .proto file. May be null,
         /// in which case it is treated as an empty array.</param>
         /// <param name="allowUnknownDependencies">Whether unknown dependencies are ignored (true) or cause an exception to be thrown (false).</param>
+        /// <param name="generatedCodeInfo">Reflection information, if any. May be null, specifically for non-generated code.</param>
         /// <exception cref="DescriptorValidationException">If <paramref name="proto"/> is not
         /// a valid descriptor. This can occur for a number of reasons, such as a field
         /// having an undefined type or because two messages were defined with the same name.</exception>
-        private static FileDescriptor BuildFrom(FileDescriptorProto proto, FileDescriptor[] dependencies, bool allowUnknownDependencies, Type[] generatedTypes)
+        private static FileDescriptor BuildFrom(FileDescriptorProto proto, FileDescriptor[] dependencies, bool allowUnknownDependencies, GeneratedCodeInfo generatedCodeInfo)
         {
             // Building descriptors involves two steps: translating and linking.
             // In the translation step (implemented by FileDescriptor's
@@ -289,7 +283,7 @@ namespace Google.Protobuf.Reflection
             }
 
             DescriptorPool pool = new DescriptorPool(dependencies);
-            FileDescriptor result = new FileDescriptor(proto, dependencies, pool, allowUnknownDependencies, generatedTypes);
+            FileDescriptor result = new FileDescriptor(proto, dependencies, pool, allowUnknownDependencies, generatedCodeInfo);
 
             // TODO(jonskeet): Reinstate these checks, or get rid of them entirely. They aren't in the Java code,
             // and fail for the CustomOptions test right now. (We get "descriptor.proto" vs "google/protobuf/descriptor.proto".)
@@ -330,19 +324,13 @@ namespace Google.Protobuf.Reflection
         /// Creates an instance for generated code.
         /// </summary>
         /// <remarks>
-        /// The <paramref name="generatedTypes"/> parameter should be null for descriptors which don't correspond to
-        /// generated types. Otherwise, the array should represent all the generated types in the file: messages then
-        /// enums. Within each message, there can be nested messages and enums, which must be specified "inline" in the array:
-        /// containing message, nested messages, nested enums - and of course each nested message may contain *more* nested messages,
-        /// etc. All messages within the descriptor should be represented, even if they do not have a generated type - any
-        /// type without a corresponding generated type (such as map entries) should respond to a null element.
-        /// For example, a file with a messages OuterMessage and InnerMessage, and enums OuterEnum and InnerEnum (where
-        /// InnerMessage and InnerEnum are nested within InnerMessage) would result in an array of
-        /// OuterMessage, InnerMessage, InnerEnum, OuterEnum.
+        /// The <paramref name="generatedCodeInfo"/> parameter should be null for descriptors which don't correspond to
+        /// generated types. Otherwise, it should be a <see cref="GeneratedCodeInfo"/> with nested types and nested
+        /// enums corresponding to the types and enums contained within the file descriptor.
         /// </remarks>
         public static FileDescriptor InternalBuildGeneratedFileFrom(byte[] descriptorData,
                                                                     FileDescriptor[] dependencies,
-                                                                    Type[] generatedTypes)
+                                                                    GeneratedCodeInfo generatedCodeInfo)
         {
             FileDescriptorProto proto;
             try
@@ -358,7 +346,7 @@ namespace Google.Protobuf.Reflection
             {
                 // When building descriptors for generated code, we allow unknown
                 // dependencies by default.
-                return BuildFrom(proto, dependencies, true, generatedTypes);
+                return BuildFrom(proto, dependencies, true, generatedCodeInfo);
             }
             catch (DescriptorValidationException e)
             {
diff --git a/csharp/src/Google.Protobuf/Reflection/GeneratedCodeInfo.cs b/csharp/src/Google.Protobuf/Reflection/GeneratedCodeInfo.cs
new file mode 100644
index 00000000..8c52cd12
--- /dev/null
+++ b/csharp/src/Google.Protobuf/Reflection/GeneratedCodeInfo.cs
@@ -0,0 +1,66 @@
+using System;
+
+namespace Google.Protobuf.Reflection
+{
+    /// <summary>
+    /// Extra information provided by generated code when initializing a message or file descriptor.
+    /// These are constructed as required, and are not long-lived. Hand-written code should
+    /// never need to use this type.
+    /// </summary>
+    public sealed class GeneratedCodeInfo
+    {
+        private static readonly string[] EmptyNames = new string[0];
+        private static readonly GeneratedCodeInfo[] EmptyCodeInfo = new GeneratedCodeInfo[0];
+
+        /// <summary>
+        /// Irrelevant for file descriptors; the CLR type for the message for message descriptors.
+        /// </summary>
+        public Type ClrType { get; private set; }
+
+        /// <summary>
+        /// Irrelevant for file descriptors; the CLR property names (in message descriptor field order)
+        /// for fields in the message for message descriptors.
+        /// </summary>
+        public string[] PropertyNames { get; private set; }
+
+        /// <summary>
+        /// Irrelevant for file descriptors; the CLR property "base" names (in message descriptor oneof order)
+        /// for oneofs in the message for message descriptors. It is expected that for a oneof name of "Foo",
+        /// there will be a "FooCase" property and a "ClearFoo" method.
+        /// </summary>
+        public string[] OneofNames { get; private set; }
+
+        /// <summary>
+        /// The reflection information for types within this file/message descriptor. Elements may be null
+        /// if there is no corresponding generated type, e.g. for map entry types.
+        /// </summary>
+        public GeneratedCodeInfo[] NestedTypes { get; private set; }
+
+        /// <summary>
+        /// The CLR types for enums within this file/message descriptor.
+        /// </summary>
+        public Type[] NestedEnums { get; private set; }
+
+        /// <summary>
+        /// Creates a GeneratedCodeInfo for a message descriptor, with nested types, nested enums, the CLR type, property names and oneof names.
+        /// Each array parameter may be null, to indicate a lack of values.
+        /// The parameter order is designed to make it feasible to format the generated code readably.
+        /// </summary>
+        public GeneratedCodeInfo(Type clrType, string[] propertyNames, string[] oneofNames, Type[] nestedEnums, GeneratedCodeInfo[] nestedTypes)
+        {
+            NestedTypes = nestedTypes ?? EmptyCodeInfo;
+            NestedEnums = nestedEnums ?? ReflectionUtil.EmptyTypes;
+            ClrType = clrType;
+            PropertyNames = propertyNames ?? EmptyNames;
+            OneofNames = oneofNames ?? EmptyNames;
+        }
+
+        /// <summary>
+        /// Creates a GeneratedCodeInfo for a file descriptor, with only types and enums.
+        /// </summary>
+        public GeneratedCodeInfo(Type[] nestedEnums, GeneratedCodeInfo[] nestedTypes)
+            : this(null, null, null, nestedEnums, nestedTypes)
+        {
+        }
+    }
+}
\ No newline at end of file
diff --git a/csharp/src/Google.Protobuf/Reflection/MessageDescriptor.cs b/csharp/src/Google.Protobuf/Reflection/MessageDescriptor.cs
index 9413cf61..b29b4b20 100644
--- a/csharp/src/Google.Protobuf/Reflection/MessageDescriptor.cs
+++ b/csharp/src/Google.Protobuf/Reflection/MessageDescriptor.cs
@@ -66,29 +66,33 @@ namespace Google.Protobuf.Reflection
         private readonly Type generatedType;
         private IDictionary<int, IFieldAccessor> fieldAccessorsByFieldNumber;
         
-        internal MessageDescriptor(DescriptorProto proto, FileDescriptor file, MessageDescriptor parent, int typeIndex, IEnumerator<Type> generatedTypeIterator)
+        internal MessageDescriptor(DescriptorProto proto, FileDescriptor file, MessageDescriptor parent, int typeIndex, GeneratedCodeInfo generatedCodeInfo)
             : base(file, file.ComputeFullName(parent, proto.Name), typeIndex)
         {
             this.proto = proto;
-            generatedType = ReflectionUtil.GetNextType(generatedTypeIterator);
-            containingType = parent;
-
-            oneofs = DescriptorUtil.ConvertAndMakeReadOnly(proto.OneofDecl,
-                                                               (oneof, index) =>
-                                                               new OneofDescriptor(oneof, file, this, index));
-
-            nestedTypes = DescriptorUtil.ConvertAndMakeReadOnly(proto.NestedType,
-                                                                (type, index) =>
-                                                                new MessageDescriptor(type, file, this, index, generatedTypeIterator));
+            generatedType = generatedCodeInfo == null ? null : generatedCodeInfo.ClrType;
 
-            enumTypes = DescriptorUtil.ConvertAndMakeReadOnly(proto.EnumType,
-                                                              (type, index) =>
-                                                              new EnumDescriptor(type, file, this, index, ReflectionUtil.GetNextType(generatedTypeIterator)));
+            containingType = parent;
 
-            // TODO(jonskeet): Sort fields first?
-            fields = DescriptorUtil.ConvertAndMakeReadOnly(proto.Field,
-                                                           (field, index) =>
-                                                           new FieldDescriptor(field, file, this, index));
+            oneofs = DescriptorUtil.ConvertAndMakeReadOnly(
+                proto.OneofDecl,
+                (oneof, index) =>
+                new OneofDescriptor(oneof, file, this, index, generatedCodeInfo == null ? null : generatedCodeInfo.OneofNames[index]));
+
+            nestedTypes = DescriptorUtil.ConvertAndMakeReadOnly(
+                proto.NestedType,
+                (type, index) =>
+                new MessageDescriptor(type, file, this, index, generatedCodeInfo == null ? null : generatedCodeInfo.NestedTypes[index]));
+
+            enumTypes = DescriptorUtil.ConvertAndMakeReadOnly(
+                proto.EnumType,
+                (type, index) =>
+                new EnumDescriptor(type, file, this, index, generatedCodeInfo == null ? null : generatedCodeInfo.NestedEnums[index]));
+
+            fields = DescriptorUtil.ConvertAndMakeReadOnly(
+                proto.Field,
+                (field, index) =>
+                new FieldDescriptor(field, file, this, index, generatedCodeInfo == null ? null : generatedCodeInfo.PropertyNames[index]));
             file.DescriptorPool.AddSymbol(this);
         }
                 
@@ -220,6 +224,6 @@ namespace Google.Protobuf.Reflection
             }
 
             fieldAccessorsByFieldNumber = new ReadOnlyDictionary<int, IFieldAccessor>(fields.ToDictionary(field => field.FieldNumber, field => field.Accessor));
-        }        
+        }
     }
 }
\ No newline at end of file
diff --git a/csharp/src/Google.Protobuf/Reflection/OneofDescriptor.cs b/csharp/src/Google.Protobuf/Reflection/OneofDescriptor.cs
index b4cc0791..a79d9de4 100644
--- a/csharp/src/Google.Protobuf/Reflection/OneofDescriptor.cs
+++ b/csharp/src/Google.Protobuf/Reflection/OneofDescriptor.cs
@@ -41,15 +41,16 @@ namespace Google.Protobuf.Reflection
         private readonly OneofDescriptorProto proto;
         private MessageDescriptor containingType;
         private IList<FieldDescriptor> fields;
-        private OneofAccessor accessor;
+        private readonly OneofAccessor accessor;
 
-        internal OneofDescriptor(OneofDescriptorProto proto, FileDescriptor file, MessageDescriptor parent, int index)
+        internal OneofDescriptor(OneofDescriptorProto proto, FileDescriptor file, MessageDescriptor parent, int index, string clrName)
             : base(file, file.ComputeFullName(parent, proto.Name), index)
         {
             this.proto = proto;
             containingType = parent;
 
             file.DescriptorPool.AddSymbol(this);
+            accessor = CreateAccessor(clrName);
         }
 
         /// <summary>
@@ -77,33 +78,23 @@ namespace Google.Protobuf.Reflection
                 }
             }
             fields = new ReadOnlyCollection<FieldDescriptor>(fieldCollection);
-            accessor = CreateAccessor();
         }
 
-        private OneofAccessor CreateAccessor()
+        private OneofAccessor CreateAccessor(string clrName)
         {
-            if (containingType.GeneratedType == null)
+            if (containingType.GeneratedType == null || clrName == null)
             {
                 return null;
             }
-            var caseProperty = containingType
-                .GeneratedType
-                .GetProperties()
-                .FirstOrDefault(p => p.IsDefined(typeof(ProtobufOneofAttribute), false) &&
-                                     p.GetCustomAttributes(typeof(ProtobufOneofAttribute), false).Cast<ProtobufOneofAttribute>().Single().Name == Name);
+            var caseProperty = containingType.GeneratedType.GetProperty(clrName + "Case");
             if (caseProperty == null)
             {
-                return null;
+                throw new DescriptorValidationException(this, "Property " + clrName + "Case not found in " + containingType.GeneratedType);
             }
-
-            var clearMethod = containingType
-                 .GeneratedType
-                 .GetMethods()
-                 .FirstOrDefault(p => p.IsDefined(typeof(ProtobufOneofAttribute), false) &&
-                                      p.GetCustomAttributes(typeof(ProtobufOneofAttribute), false).Cast<ProtobufOneofAttribute>().Single().Name == Name);
+            var clearMethod = containingType.GeneratedType.GetMethod("Clear" + clrName, ReflectionUtil.EmptyTypes);
             if (clearMethod == null)
             {
-                return null;
+                throw new DescriptorValidationException(this, "Method Clear" + clrName + " not found in " + containingType.GeneratedType);
             }
 
             return new OneofAccessor(caseProperty, clearMethod, this);
diff --git a/csharp/src/Google.Protobuf/Reflection/ProtobufFieldAttribute.cs b/csharp/src/Google.Protobuf/Reflection/ProtobufFieldAttribute.cs
deleted file mode 100644
index a59caea7..00000000
--- a/csharp/src/Google.Protobuf/Reflection/ProtobufFieldAttribute.cs
+++ /dev/null
@@ -1,58 +0,0 @@
-#region Copyright notice and license
-// Protocol Buffers - Google's data interchange format
-// Copyright 2015 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#endregion
-using System;
-
-namespace Google.Protobuf.Reflection
-{
-    /// <summary>
-    /// Attribute applied to a generated property corresponding to a field in a .proto file.
-    /// </summary>
-    [AttributeUsage(AttributeTargets.Property, AllowMultiple = false)]
-    public sealed class ProtobufFieldAttribute : Attribute
-    {
-        /// <summary>
-        /// The field number in the original .proto file.
-        /// </summary>
-        public int Number { get; set; }
-        
-        /// <summary>
-        /// The field name in the original .proto file.
-        /// </summary>
-        public string Name { get; set; }
-
-        public ProtobufFieldAttribute(int number, string name)
-        {
-            this.Number = number;
-            this.Name = name;
-        }
-    }
-}
diff --git a/csharp/src/Google.Protobuf/Reflection/ProtobufOneofAttribute.cs b/csharp/src/Google.Protobuf/Reflection/ProtobufOneofAttribute.cs
deleted file mode 100644
index 74ad8c53..00000000
--- a/csharp/src/Google.Protobuf/Reflection/ProtobufOneofAttribute.cs
+++ /dev/null
@@ -1,52 +0,0 @@
-#region Copyright notice and license
-// Protocol Buffers - Google's data interchange format
-// Copyright 2015 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#endregion
-using System;
-
-namespace Google.Protobuf.Reflection
-{
-    /// <summary>
-    /// Attribute applied to the "case" property or "clear" method corresponding to a oneof in a .proto file.
-    /// </summary>
-    [AttributeUsage(AttributeTargets.Property | AttributeTargets.Method, AllowMultiple = false)]
-    public sealed class ProtobufOneofAttribute : Attribute
-    {
-        /// <summary>
-        /// The oneof name in the original .proto file.
-        /// </summary>
-        public string Name { get; set; }
-
-        public ProtobufOneofAttribute(string name)
-        {
-            this.Name = name;
-        }
-    }
-}
diff --git a/csharp/src/Google.Protobuf/Reflection/ReflectionUtil.cs b/csharp/src/Google.Protobuf/Reflection/ReflectionUtil.cs
index ec222dc1..5b3cbb36 100644
--- a/csharp/src/Google.Protobuf/Reflection/ReflectionUtil.cs
+++ b/csharp/src/Google.Protobuf/Reflection/ReflectionUtil.cs
@@ -102,25 +102,6 @@ namespace Google.Protobuf.Reflection
             Expression castTarget = Expression.Convert(targetParameter, method.DeclaringType);
             Expression call = Expression.Call(castTarget, method);
             return Expression.Lambda<Action<object>>(call, targetParameter).Compile();
-        }
-
-        /// <summary>
-        /// Returns the next type from an iterator of types, unless the iterator is a null reference,
-        /// in which case null is returned.
-        /// </summary>
-        internal static Type GetNextType(IEnumerator<Type> generatedTypeIterator)
-        {
-            if (generatedTypeIterator == null)
-            {
-                return null;
-            }
-            if (!generatedTypeIterator.MoveNext())
-            {
-                // This parameter name corresponds to any public method supplying the generated types to start with.
-                throw new ArgumentException("More generated types left over after consuming all expected ones", "generatedTypes");
-            }
-            return generatedTypeIterator.Current;
-        }
-
+        }        
     }
 }
\ No newline at end of file
diff --git a/src/google/protobuf/compiler/csharp/csharp_field_base.cc b/src/google/protobuf/compiler/csharp/csharp_field_base.cc
index d327e267..2459d457 100644
--- a/src/google/protobuf/compiler/csharp/csharp_field_base.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_field_base.cc
@@ -74,7 +74,6 @@ void FieldGeneratorBase::SetCommonFieldVariables(
 
   (*variables)["property_name"] = property_name();
   (*variables)["type_name"] = type_name();
-  (*variables)["original_name"] = descriptor_->name();
   (*variables)["name"] = name();
   (*variables)["descriptor_name"] = descriptor_->name();
   (*variables)["default_value"] = default_value();
@@ -431,10 +430,6 @@ std::string FieldGeneratorBase::capitalized_type_name() {
   }
 }
 
-std::string FieldGeneratorBase::field_ordinal() {
-  return SimpleItoa(fieldOrdinal_);
-}
-
 }  // namespace csharp
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/csharp/csharp_field_base.h b/src/google/protobuf/compiler/csharp/csharp_field_base.h
index 4761dc49..d83543bd 100644
--- a/src/google/protobuf/compiler/csharp/csharp_field_base.h
+++ b/src/google/protobuf/compiler/csharp/csharp_field_base.h
@@ -85,7 +85,6 @@ class FieldGeneratorBase : public SourceGeneratorBase {
   std::string default_value(const FieldDescriptor* descriptor);
   std::string number();
   std::string capitalized_type_name();
-  std::string field_ordinal();
 
  private:
   void SetCommonFieldVariables(map<string, string>* variables);
diff --git a/src/google/protobuf/compiler/csharp/csharp_map_field.cc b/src/google/protobuf/compiler/csharp/csharp_map_field.cc
index bdbfd92b..cba24a59 100644
--- a/src/google/protobuf/compiler/csharp/csharp_map_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_map_field.cc
@@ -79,7 +79,6 @@ void MapFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ pbc::MapField<$key_type_name$, $value_type_name$> $property_name$ {\n"
     "  get { return $name$_; }\n"
     "}\n");
diff --git a/src/google/protobuf/compiler/csharp/csharp_message.cc b/src/google/protobuf/compiler/csharp/csharp_message.cc
index 42fd5065..6a22a336 100644
--- a/src/google/protobuf/compiler/csharp/csharp_message.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_message.cc
@@ -115,19 +115,6 @@ void MessageGenerator::Generate(io::Printer* printer) {
       vars,
       "private static readonly pb::MessageParser<$class_name$> _parser = new pb::MessageParser<$class_name$>(() => new $class_name$());\n"
       "public static pb::MessageParser<$class_name$> Parser { get { return _parser; } }\n\n");
-  printer->Print(
-    "private static readonly string[] _fieldNames = "
-    "new string[] { $slash$$field_names$$slash$ };\n",
-    "field_names", JoinStrings(field_names(), "\", \""),
-      "slash", field_names().size() > 0 ? "\"" : "");
-  std::vector<std::string> tags;
-  for (int i = 0; i < field_names().size(); i++) {
-    uint32 tag = FixedMakeTag(descriptor_->FindFieldByName(field_names()[i]));
-    tags.push_back(SimpleItoa(tag));
-  }
-  printer->Print(
-    "private static readonly uint[] _fieldTags = new uint[] { $tags$ };\n",
-    "tags", JoinStrings(tags, ", "));
 
   // Access the message descriptor via the relevant file descriptor or containing message descriptor.
   if (!descriptor_->containing_type()) {
diff --git a/src/google/protobuf/compiler/csharp/csharp_message_field.cc b/src/google/protobuf/compiler/csharp/csharp_message_field.cc
index c2b6ff76..d2c3a88b 100644
--- a/src/google/protobuf/compiler/csharp/csharp_message_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_message_field.cc
@@ -64,7 +64,6 @@ void MessageFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ $type_name$ $property_name$ {\n"
     "  get { return $name$_; }\n"
     "  set {\n"
@@ -159,7 +158,6 @@ void MessageOneofFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ $type_name$ $property_name$ {\n"
     "  get { return $has_property_check$ ? ($type_name$) $oneof_name$_ : null; }\n"
     "  set {\n"
diff --git a/src/google/protobuf/compiler/csharp/csharp_primitive_field.cc b/src/google/protobuf/compiler/csharp/csharp_primitive_field.cc
index 2c9338bd..4454ef02 100644
--- a/src/google/protobuf/compiler/csharp/csharp_primitive_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_primitive_field.cc
@@ -71,7 +71,6 @@ void PrimitiveFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ $type_name$ $property_name$ {\n"
     "  get { return $name$_; }\n"
     "  set {\n"
@@ -175,7 +174,6 @@ void PrimitiveOneofFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ $type_name$ $property_name$ {\n"
     "  get { return $has_property_check$ ? ($type_name$) $oneof_name$_ : $default_value$; }\n"
     "  set {\n"
diff --git a/src/google/protobuf/compiler/csharp/csharp_repeated_enum_field.cc b/src/google/protobuf/compiler/csharp/csharp_repeated_enum_field.cc
index 60d06154..c1b29e2b 100644
--- a/src/google/protobuf/compiler/csharp/csharp_repeated_enum_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_repeated_enum_field.cc
@@ -65,7 +65,6 @@ void RepeatedEnumFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ pbc::RepeatedField<$type_name$> $property_name$ {\n"
     "  get { return $name$_; }\n"
     "}\n");
diff --git a/src/google/protobuf/compiler/csharp/csharp_repeated_message_field.cc b/src/google/protobuf/compiler/csharp/csharp_repeated_message_field.cc
index 921798b0..d939fc79 100644
--- a/src/google/protobuf/compiler/csharp/csharp_repeated_message_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_repeated_message_field.cc
@@ -78,7 +78,6 @@ void RepeatedMessageFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ pbc::RepeatedField<$type_name$> $property_name$ {\n"
     "  get { return $name$_; }\n"
     "}\n");
diff --git a/src/google/protobuf/compiler/csharp/csharp_repeated_primitive_field.cc b/src/google/protobuf/compiler/csharp/csharp_repeated_primitive_field.cc
index bcfb9936..5b5d9b3d 100644
--- a/src/google/protobuf/compiler/csharp/csharp_repeated_primitive_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_repeated_primitive_field.cc
@@ -65,7 +65,6 @@ void RepeatedPrimitiveFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ pbc::RepeatedField<$type_name$> $property_name$ {\n"
     "  get { return $name$_; }\n"
     "}\n");
diff --git a/src/google/protobuf/compiler/csharp/csharp_umbrella_class.cc b/src/google/protobuf/compiler/csharp/csharp_umbrella_class.cc
index 3f39250e..6eb1547e 100644
--- a/src/google/protobuf/compiler/csharp/csharp_umbrella_class.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_umbrella_class.cc
@@ -36,6 +36,7 @@
 #include <google/protobuf/descriptor.pb.h>
 #include <google/protobuf/io/printer.h>
 #include <google/protobuf/io/zero_copy_stream.h>
+#include <google/protobuf/stubs/strutil.h>
 
 
 #include <google/protobuf/compiler/csharp/csharp_enum.h>
@@ -168,10 +169,10 @@ void UmbrellaClassGenerator::WriteDescriptor(io::Printer* printer) {
     printer->Print("\"$base64$\", \n", "base64", base64.substr(0, 60));
     base64 = base64.substr(60);
   }
-  printer->Outdent();
   printer->Print("\"$base64$\"));\n", "base64", base64);
   printer->Outdent();
   printer->Outdent();
+  printer->Outdent();
 
   // -----------------------------------------------------------------
   // Invoke InternalBuildGeneratedFileFrom() to build the file.
@@ -184,34 +185,108 @@ void UmbrellaClassGenerator::WriteDescriptor(io::Printer* printer) {
       "full_umbrella_class_name",
       GetFullUmbrellaClassName(file_->dependency(i)));
   }
-  // Specify all the generated types (messages and enums), recursively, as an array. 
   printer->Print("},\n"
-    "    new global::System.Type[] { ");
-  for (int i = 0; i < file_->message_type_count(); i++) {
-    WriteTypeLiterals(file_->message_type(i), printer);
+      "    new pbr::GeneratedCodeInfo(");
+  // Specify all the generated code information, recursively.
+  if (file_->enum_type_count() > 0) {
+      printer->Print("new[] {");
+      for (int i = 0; i < file_->enum_type_count(); i++) {
+          printer->Print("typeof($type_name$), ", "type_name", GetClassName(file_->enum_type(i)));
+      }
+      printer->Print("}, ");
+  }
+  else {
+      printer->Print("null, ");
+  }
+  if (file_->message_type_count() > 0) {
+      printer->Print("new pbr::GeneratedCodeInfo[] {\n");
+      printer->Indent();
+      printer->Indent();
+      printer->Indent();
+      for (int i = 0; i < file_->message_type_count(); i++) {
+          WriteGeneratedCodeInfo(file_->message_type(i), printer, i == file_->message_type_count() - 1);
+      }
+      printer->Outdent();
+      printer->Print("\n}));\n");
+      printer->Outdent();
+      printer->Outdent();
   }
-  for (int i = 0; i < file_->enum_type_count(); i++) {
-    printer->Print("typeof($type_name$), ", "type_name", GetClassName(file_->enum_type(i)));
+  else {
+      printer->Print("null));\n");
   }
-  printer->Print("});\n");
 
   printer->Outdent();
   printer->Print("}\n");
   printer->Print("#endregion\n\n");
 }
 
-void UmbrellaClassGenerator::WriteTypeLiterals(const Descriptor* descriptor, io::Printer* printer) {
-    if (IsMapEntryMessage(descriptor)) {
-        printer->Print("null, ");
-        return;
-    }
-    printer->Print("typeof($type_name$), ", "type_name", GetClassName(descriptor));
-    for (int i = 0; i < descriptor->nested_type_count(); i++) {
-        WriteTypeLiterals(descriptor->nested_type(i), printer);
-    }
-    for (int i = 0; i < descriptor->enum_type_count(); i++) {
-        printer->Print("typeof($type_name$), ", "type_name", GetClassName(descriptor->enum_type(i)));
-    }
+// Write out the generated code for a particular message. This consists of the CLR type, property names
+// corresponding to fields, names corresponding to oneofs, nested enums, and nested types. Each array part
+// can be specified as null if it would be empty, to make the generated code somewhat simpler to read.
+// We write a line break at the end of each generated code info, so that in the final file we'll see all
+// the types, pre-ordered depth first, one per line. The indentation will be slightly unusual,
+// in that it will look like a single array when it's actually constructing a tree, but it'll be easy to
+// read even with multiple levels of nesting.
+// The "last" parameter indicates whether this message descriptor is the last one being printed in this immediate
+// context. It governs whether or not a trailing comma and newline is written after the constructor, effectively
+// just controlling the formatting in the generated code.
+void UmbrellaClassGenerator::WriteGeneratedCodeInfo(const Descriptor* descriptor, io::Printer* printer, bool last) {
+  if (IsMapEntryMessage(descriptor)) {
+    printer->Print("null, ");
+    return;
+  }
+  // Generated message type
+  printer->Print("new pbr::GeneratedCodeInfo(typeof($type_name$), ", "type_name", GetClassName(descriptor));
+  
+  // Fields
+  if (descriptor->field_count() > 0) {
+      std::vector<std::string> fields;
+      for (int i = 0; i < descriptor->field_count(); i++) {
+          fields.push_back(GetPropertyName(descriptor->field(i)));
+      }
+      printer->Print("new[]{ \"$fields$\" }, ", "fields", JoinStrings(fields, "\", \""));
+  }
+  else {
+      printer->Print("null, ");
+  }
+
+  // Oneofs
+  if (descriptor->oneof_decl_count() > 0) {
+      std::vector<std::string> oneofs;
+      for (int i = 0; i < descriptor->oneof_decl_count(); i++) {
+          oneofs.push_back(UnderscoresToCamelCase(descriptor->oneof_decl(i)->name(), true));
+      }
+      printer->Print("new[]{ \"$oneofs$\" }, ", "oneofs", JoinStrings(oneofs, "\", \""));
+  }
+  else {
+      printer->Print("null, ");
+  }
+
+  // Nested enums
+  if (descriptor->enum_type_count() > 0) {
+      std::vector<std::string> enums;
+      for (int i = 0; i < descriptor->enum_type_count(); i++) {
+          enums.push_back(GetClassName(descriptor->enum_type(i)));
+      }
+      printer->Print("new[]{ typeof($enums$) }, ", "enums", JoinStrings(enums, "), typeof("));
+  }
+  else {
+      printer->Print("null, ");
+  }
+
+  // Nested types
+  if (descriptor->nested_type_count() > 0) {
+      // Need to specify array type explicitly here, as all elements may be null. 
+      printer->Print("new pbr::GeneratedCodeInfo[] { ");
+      for (int i = 0; i < descriptor->nested_type_count(); i++) {
+          WriteGeneratedCodeInfo(descriptor->nested_type(i), printer, i == descriptor->nested_type_count() - 1);
+      }
+      printer->Print("}");
+  }
+  else {
+      printer->Print("null");
+  }
+  printer->Print(last ? ")" : "),\n");
 }
 
 }  // namespace csharp
diff --git a/src/google/protobuf/compiler/csharp/csharp_umbrella_class.h b/src/google/protobuf/compiler/csharp/csharp_umbrella_class.h
index db1092a9..b8bd2133 100644
--- a/src/google/protobuf/compiler/csharp/csharp_umbrella_class.h
+++ b/src/google/protobuf/compiler/csharp/csharp_umbrella_class.h
@@ -57,7 +57,7 @@ class UmbrellaClassGenerator : public SourceGeneratorBase {
 
   void WriteIntroduction(io::Printer* printer);
   void WriteDescriptor(io::Printer* printer);
-  void WriteTypeLiterals(const Descriptor* descriptor, io::Printer* printer);
+  void WriteGeneratedCodeInfo(const Descriptor* descriptor, io::Printer* printer, bool last);
 
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(UmbrellaClassGenerator);
 };
diff --git a/src/google/protobuf/compiler/csharp/csharp_wrapper_field.cc b/src/google/protobuf/compiler/csharp/csharp_wrapper_field.cc
index d6cd0a10..75ef5e50 100644
--- a/src/google/protobuf/compiler/csharp/csharp_wrapper_field.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_wrapper_field.cc
@@ -73,7 +73,6 @@ void WrapperFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ $type_name$ $property_name$ {\n"
     "  get { return $name$_; }\n"
     "  set {\n"
@@ -170,7 +169,6 @@ void WrapperOneofFieldGenerator::GenerateMembers(io::Printer* printer) {
   AddDeprecatedFlag(printer);
   printer->Print(
     variables_,
-    "[pbr::ProtobufField($number$, \"$original_name$\")]\n"
     "$access_level$ $type_name$ $property_name$ {\n"
     "  get { return $has_property_check$ ? ($type_name$) $oneof_name$_ : ($type_name$) null; }\n"
     "  set {\n"