1 files changed, 822 insertions, 231 deletions

diff --git a/src/ProtocolBuffers.Test/TestProtos/UnitTestCustomOptionsProtoFile.cs b/src/ProtocolBuffers.Test/TestProtos/UnitTestCustomOptionsProtoFile.cs
index 0b1be422..93d7fb9c 100644
--- a/src/ProtocolBuffers.Test/TestProtos/UnitTestCustomOptionsProtoFile.cs
+++ b/src/ProtocolBuffers.Test/TestProtos/UnitTestCustomOptionsProtoFile.cs
@@ -1,5 +1,5 @@
 // Generated by ProtoGen, Version=2.3.0.277, Culture=neutral, PublicKeyToken=17b3b1f090c3ea48.  DO NOT EDIT!

-#pragma warning disable 1591

+#pragma warning disable 1591, 0612

 #region Designer generated code

 

 using pb = global::Google.ProtocolBuffers;

@@ -400,7 +400,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class TestMessageWithCustomOptions : pb::GeneratedMessage<TestMessageWithCustomOptions, TestMessageWithCustomOptions.Builder> {

-    private static readonly TestMessageWithCustomOptions defaultInstance = new Builder().BuildPartial();

+    private TestMessageWithCustomOptions() { }

+    private static readonly TestMessageWithCustomOptions defaultInstance = new TestMessageWithCustomOptions().MakeReadOnly();

     private static readonly string[] _testMessageWithCustomOptionsFieldNames = new string[] { "field1" };

     private static readonly uint[] _testMessageWithCustomOptionsFieldTags = new uint[] { 10 };

     public static TestMessageWithCustomOptions DefaultInstance {

@@ -408,7 +409,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override TestMessageWithCustomOptions DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override TestMessageWithCustomOptions ThisMessage {

@@ -509,11 +510,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static TestMessageWithCustomOptions ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private TestMessageWithCustomOptions MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(TestMessageWithCustomOptions prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -523,21 +528,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(TestMessageWithCustomOptions cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

       

-      TestMessageWithCustomOptions result = new TestMessageWithCustomOptions();

+      private bool resultIsReadOnly;

+      private TestMessageWithCustomOptions result;

+      

+      private TestMessageWithCustomOptions PrepareBuilder() {

+        if (resultIsReadOnly) {

+          TestMessageWithCustomOptions original = result;

+          result = new TestMessageWithCustomOptions();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override TestMessageWithCustomOptions MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new TestMessageWithCustomOptions();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -549,12 +581,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override TestMessageWithCustomOptions BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        TestMessageWithCustomOptions returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -568,6 +599,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(TestMessageWithCustomOptions other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.TestMessageWithCustomOptions.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasField1) {

           Field1 = other.Field1;

         }

@@ -580,6 +612,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -636,11 +669,13 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       public Builder SetField1(string value) {

         pb::ThrowHelper.ThrowIfNull(value, "value");

+        PrepareBuilder();

         result.hasField1 = true;

         result.field1_ = value;

         return this;

       }

       public Builder ClearField1() {

+        PrepareBuilder();

         result.hasField1 = false;

         result.field1_ = "";

         return this;

@@ -655,7 +690,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class CustomOptionFooRequest : pb::GeneratedMessage<CustomOptionFooRequest, CustomOptionFooRequest.Builder> {

-    private static readonly CustomOptionFooRequest defaultInstance = new Builder().BuildPartial();

+    private CustomOptionFooRequest() { }

+    private static readonly CustomOptionFooRequest defaultInstance = new CustomOptionFooRequest().MakeReadOnly();

     private static readonly string[] _customOptionFooRequestFieldNames = new string[] {  };

     private static readonly uint[] _customOptionFooRequestFieldTags = new uint[] {  };

     public static CustomOptionFooRequest DefaultInstance {

@@ -663,7 +699,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override CustomOptionFooRequest DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override CustomOptionFooRequest ThisMessage {

@@ -733,11 +769,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static CustomOptionFooRequest ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private CustomOptionFooRequest MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(CustomOptionFooRequest prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -747,21 +787,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(CustomOptionFooRequest cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

       

-      CustomOptionFooRequest result = new CustomOptionFooRequest();

+      private bool resultIsReadOnly;

+      private CustomOptionFooRequest result;

+      

+      private CustomOptionFooRequest PrepareBuilder() {

+        if (resultIsReadOnly) {

+          CustomOptionFooRequest original = result;

+          result = new CustomOptionFooRequest();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override CustomOptionFooRequest MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new CustomOptionFooRequest();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -773,12 +840,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override CustomOptionFooRequest BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        CustomOptionFooRequest returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -792,6 +858,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(CustomOptionFooRequest other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.CustomOptionFooRequest.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -801,6 +868,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -853,7 +921,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class CustomOptionFooResponse : pb::GeneratedMessage<CustomOptionFooResponse, CustomOptionFooResponse.Builder> {

-    private static readonly CustomOptionFooResponse defaultInstance = new Builder().BuildPartial();

+    private CustomOptionFooResponse() { }

+    private static readonly CustomOptionFooResponse defaultInstance = new CustomOptionFooResponse().MakeReadOnly();

     private static readonly string[] _customOptionFooResponseFieldNames = new string[] {  };

     private static readonly uint[] _customOptionFooResponseFieldTags = new uint[] {  };

     public static CustomOptionFooResponse DefaultInstance {

@@ -861,7 +930,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override CustomOptionFooResponse DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override CustomOptionFooResponse ThisMessage {

@@ -931,11 +1000,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static CustomOptionFooResponse ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private CustomOptionFooResponse MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(CustomOptionFooResponse prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -945,21 +1018,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(CustomOptionFooResponse cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

       

-      CustomOptionFooResponse result = new CustomOptionFooResponse();

+      private bool resultIsReadOnly;

+      private CustomOptionFooResponse result;

+      

+      private CustomOptionFooResponse PrepareBuilder() {

+        if (resultIsReadOnly) {

+          CustomOptionFooResponse original = result;

+          result = new CustomOptionFooResponse();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override CustomOptionFooResponse MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new CustomOptionFooResponse();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -971,12 +1071,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override CustomOptionFooResponse BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        CustomOptionFooResponse returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -990,6 +1089,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(CustomOptionFooResponse other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.CustomOptionFooResponse.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -999,6 +1099,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -1051,7 +1152,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class DummyMessageContainingEnum : pb::GeneratedMessage<DummyMessageContainingEnum, DummyMessageContainingEnum.Builder> {

-    private static readonly DummyMessageContainingEnum defaultInstance = new Builder().BuildPartial();

+    private DummyMessageContainingEnum() { }

+    private static readonly DummyMessageContainingEnum defaultInstance = new DummyMessageContainingEnum().MakeReadOnly();

     private static readonly string[] _dummyMessageContainingEnumFieldNames = new string[] {  };

     private static readonly uint[] _dummyMessageContainingEnumFieldTags = new uint[] {  };

     public static DummyMessageContainingEnum DefaultInstance {

@@ -1059,7 +1161,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override DummyMessageContainingEnum DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override DummyMessageContainingEnum ThisMessage {

@@ -1144,11 +1246,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static DummyMessageContainingEnum ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private DummyMessageContainingEnum MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(DummyMessageContainingEnum prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -1158,21 +1264,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(DummyMessageContainingEnum cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

       

-      DummyMessageContainingEnum result = new DummyMessageContainingEnum();

+      private bool resultIsReadOnly;

+      private DummyMessageContainingEnum result;

+      

+      private DummyMessageContainingEnum PrepareBuilder() {

+        if (resultIsReadOnly) {

+          DummyMessageContainingEnum original = result;

+          result = new DummyMessageContainingEnum();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override DummyMessageContainingEnum MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new DummyMessageContainingEnum();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -1184,12 +1317,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override DummyMessageContainingEnum BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        DummyMessageContainingEnum returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -1203,6 +1335,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(DummyMessageContainingEnum other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.DummyMessageContainingEnum.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -1212,6 +1345,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -1264,7 +1398,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class DummyMessageInvalidAsOptionType : pb::GeneratedMessage<DummyMessageInvalidAsOptionType, DummyMessageInvalidAsOptionType.Builder> {

-    private static readonly DummyMessageInvalidAsOptionType defaultInstance = new Builder().BuildPartial();

+    private DummyMessageInvalidAsOptionType() { }

+    private static readonly DummyMessageInvalidAsOptionType defaultInstance = new DummyMessageInvalidAsOptionType().MakeReadOnly();

     private static readonly string[] _dummyMessageInvalidAsOptionTypeFieldNames = new string[] {  };

     private static readonly uint[] _dummyMessageInvalidAsOptionTypeFieldTags = new uint[] {  };

     public static DummyMessageInvalidAsOptionType DefaultInstance {

@@ -1272,7 +1407,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override DummyMessageInvalidAsOptionType DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override DummyMessageInvalidAsOptionType ThisMessage {

@@ -1342,11 +1477,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static DummyMessageInvalidAsOptionType ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private DummyMessageInvalidAsOptionType MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(DummyMessageInvalidAsOptionType prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -1356,21 +1495,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(DummyMessageInvalidAsOptionType cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

+      

+      private bool resultIsReadOnly;

+      private DummyMessageInvalidAsOptionType result;

       

-      DummyMessageInvalidAsOptionType result = new DummyMessageInvalidAsOptionType();

+      private DummyMessageInvalidAsOptionType PrepareBuilder() {

+        if (resultIsReadOnly) {

+          DummyMessageInvalidAsOptionType original = result;

+          result = new DummyMessageInvalidAsOptionType();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override DummyMessageInvalidAsOptionType MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new DummyMessageInvalidAsOptionType();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -1382,12 +1548,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override DummyMessageInvalidAsOptionType BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        DummyMessageInvalidAsOptionType returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -1401,6 +1566,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(DummyMessageInvalidAsOptionType other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.DummyMessageInvalidAsOptionType.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -1410,6 +1576,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -1462,7 +1629,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class CustomOptionMinIntegerValues : pb::GeneratedMessage<CustomOptionMinIntegerValues, CustomOptionMinIntegerValues.Builder> {

-    private static readonly CustomOptionMinIntegerValues defaultInstance = new Builder().BuildPartial();

+    private CustomOptionMinIntegerValues() { }

+    private static readonly CustomOptionMinIntegerValues defaultInstance = new CustomOptionMinIntegerValues().MakeReadOnly();

     private static readonly string[] _customOptionMinIntegerValuesFieldNames = new string[] {  };

     private static readonly uint[] _customOptionMinIntegerValuesFieldTags = new uint[] {  };

     public static CustomOptionMinIntegerValues DefaultInstance {

@@ -1470,7 +1638,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override CustomOptionMinIntegerValues DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override CustomOptionMinIntegerValues ThisMessage {

@@ -1540,11 +1708,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static CustomOptionMinIntegerValues ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private CustomOptionMinIntegerValues MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(CustomOptionMinIntegerValues prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -1554,21 +1726,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(CustomOptionMinIntegerValues cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

       

-      CustomOptionMinIntegerValues result = new CustomOptionMinIntegerValues();

+      private bool resultIsReadOnly;

+      private CustomOptionMinIntegerValues result;

+      

+      private CustomOptionMinIntegerValues PrepareBuilder() {

+        if (resultIsReadOnly) {

+          CustomOptionMinIntegerValues original = result;

+          result = new CustomOptionMinIntegerValues();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override CustomOptionMinIntegerValues MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new CustomOptionMinIntegerValues();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -1580,12 +1779,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override CustomOptionMinIntegerValues BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        CustomOptionMinIntegerValues returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -1599,6 +1797,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(CustomOptionMinIntegerValues other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.CustomOptionMinIntegerValues.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -1608,6 +1807,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -1660,7 +1860,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class CustomOptionMaxIntegerValues : pb::GeneratedMessage<CustomOptionMaxIntegerValues, CustomOptionMaxIntegerValues.Builder> {

-    private static readonly CustomOptionMaxIntegerValues defaultInstance = new Builder().BuildPartial();

+    private CustomOptionMaxIntegerValues() { }

+    private static readonly CustomOptionMaxIntegerValues defaultInstance = new CustomOptionMaxIntegerValues().MakeReadOnly();

     private static readonly string[] _customOptionMaxIntegerValuesFieldNames = new string[] {  };

     private static readonly uint[] _customOptionMaxIntegerValuesFieldTags = new uint[] {  };

     public static CustomOptionMaxIntegerValues DefaultInstance {

@@ -1668,7 +1869,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override CustomOptionMaxIntegerValues DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override CustomOptionMaxIntegerValues ThisMessage {

@@ -1738,11 +1939,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static CustomOptionMaxIntegerValues ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private CustomOptionMaxIntegerValues MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(CustomOptionMaxIntegerValues prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -1752,21 +1957,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(CustomOptionMaxIntegerValues cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

       

-      CustomOptionMaxIntegerValues result = new CustomOptionMaxIntegerValues();

+      private bool resultIsReadOnly;

+      private CustomOptionMaxIntegerValues result;

+      

+      private CustomOptionMaxIntegerValues PrepareBuilder() {

+        if (resultIsReadOnly) {

+          CustomOptionMaxIntegerValues original = result;

+          result = new CustomOptionMaxIntegerValues();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override CustomOptionMaxIntegerValues MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new CustomOptionMaxIntegerValues();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -1778,12 +2010,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override CustomOptionMaxIntegerValues BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        CustomOptionMaxIntegerValues returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -1797,6 +2028,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(CustomOptionMaxIntegerValues other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.CustomOptionMaxIntegerValues.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -1806,6 +2038,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -1858,7 +2091,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class CustomOptionOtherValues : pb::GeneratedMessage<CustomOptionOtherValues, CustomOptionOtherValues.Builder> {

-    private static readonly CustomOptionOtherValues defaultInstance = new Builder().BuildPartial();

+    private CustomOptionOtherValues() { }

+    private static readonly CustomOptionOtherValues defaultInstance = new CustomOptionOtherValues().MakeReadOnly();

     private static readonly string[] _customOptionOtherValuesFieldNames = new string[] {  };

     private static readonly uint[] _customOptionOtherValuesFieldTags = new uint[] {  };

     public static CustomOptionOtherValues DefaultInstance {

@@ -1866,7 +2100,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override CustomOptionOtherValues DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override CustomOptionOtherValues ThisMessage {

@@ -1936,11 +2170,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static CustomOptionOtherValues ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private CustomOptionOtherValues MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(CustomOptionOtherValues prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -1950,21 +2188,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(CustomOptionOtherValues cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

       

-      CustomOptionOtherValues result = new CustomOptionOtherValues();

+      private bool resultIsReadOnly;

+      private CustomOptionOtherValues result;

+      

+      private CustomOptionOtherValues PrepareBuilder() {

+        if (resultIsReadOnly) {

+          CustomOptionOtherValues original = result;

+          result = new CustomOptionOtherValues();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override CustomOptionOtherValues MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new CustomOptionOtherValues();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -1976,12 +2241,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override CustomOptionOtherValues BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        CustomOptionOtherValues returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -1995,6 +2259,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(CustomOptionOtherValues other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.CustomOptionOtherValues.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -2004,6 +2269,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -2056,7 +2322,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class SettingRealsFromPositiveInts : pb::GeneratedMessage<SettingRealsFromPositiveInts, SettingRealsFromPositiveInts.Builder> {

-    private static readonly SettingRealsFromPositiveInts defaultInstance = new Builder().BuildPartial();

+    private SettingRealsFromPositiveInts() { }

+    private static readonly SettingRealsFromPositiveInts defaultInstance = new SettingRealsFromPositiveInts().MakeReadOnly();

     private static readonly string[] _settingRealsFromPositiveIntsFieldNames = new string[] {  };

     private static readonly uint[] _settingRealsFromPositiveIntsFieldTags = new uint[] {  };

     public static SettingRealsFromPositiveInts DefaultInstance {

@@ -2064,7 +2331,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override SettingRealsFromPositiveInts DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override SettingRealsFromPositiveInts ThisMessage {

@@ -2134,11 +2401,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static SettingRealsFromPositiveInts ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private SettingRealsFromPositiveInts MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(SettingRealsFromPositiveInts prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -2148,21 +2419,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(SettingRealsFromPositiveInts cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

+      

+      private bool resultIsReadOnly;

+      private SettingRealsFromPositiveInts result;

+      

+      private SettingRealsFromPositiveInts PrepareBuilder() {

+        if (resultIsReadOnly) {

+          SettingRealsFromPositiveInts original = result;

+          result = new SettingRealsFromPositiveInts();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      SettingRealsFromPositiveInts result = new SettingRealsFromPositiveInts();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override SettingRealsFromPositiveInts MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new SettingRealsFromPositiveInts();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -2174,12 +2472,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override SettingRealsFromPositiveInts BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        SettingRealsFromPositiveInts returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -2193,6 +2490,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(SettingRealsFromPositiveInts other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.SettingRealsFromPositiveInts.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -2202,6 +2500,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -2254,7 +2553,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class SettingRealsFromNegativeInts : pb::GeneratedMessage<SettingRealsFromNegativeInts, SettingRealsFromNegativeInts.Builder> {

-    private static readonly SettingRealsFromNegativeInts defaultInstance = new Builder().BuildPartial();

+    private SettingRealsFromNegativeInts() { }

+    private static readonly SettingRealsFromNegativeInts defaultInstance = new SettingRealsFromNegativeInts().MakeReadOnly();

     private static readonly string[] _settingRealsFromNegativeIntsFieldNames = new string[] {  };

     private static readonly uint[] _settingRealsFromNegativeIntsFieldTags = new uint[] {  };

     public static SettingRealsFromNegativeInts DefaultInstance {

@@ -2262,7 +2562,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override SettingRealsFromNegativeInts DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override SettingRealsFromNegativeInts ThisMessage {

@@ -2332,11 +2632,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static SettingRealsFromNegativeInts ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private SettingRealsFromNegativeInts MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(SettingRealsFromNegativeInts prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -2346,21 +2650,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(SettingRealsFromNegativeInts cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

+      

+      private bool resultIsReadOnly;

+      private SettingRealsFromNegativeInts result;

+      

+      private SettingRealsFromNegativeInts PrepareBuilder() {

+        if (resultIsReadOnly) {

+          SettingRealsFromNegativeInts original = result;

+          result = new SettingRealsFromNegativeInts();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      SettingRealsFromNegativeInts result = new SettingRealsFromNegativeInts();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override SettingRealsFromNegativeInts MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new SettingRealsFromNegativeInts();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -2372,12 +2703,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override SettingRealsFromNegativeInts BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        SettingRealsFromNegativeInts returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -2391,6 +2721,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(SettingRealsFromNegativeInts other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.SettingRealsFromNegativeInts.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -2400,6 +2731,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -2452,7 +2784,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class ComplexOptionType1 : pb::ExtendableMessage<ComplexOptionType1, ComplexOptionType1.Builder> {

-    private static readonly ComplexOptionType1 defaultInstance = new Builder().BuildPartial();

+    private ComplexOptionType1() { }

+    private static readonly ComplexOptionType1 defaultInstance = new ComplexOptionType1().MakeReadOnly();

     private static readonly string[] _complexOptionType1FieldNames = new string[] { "foo", "foo2", "foo3" };

     private static readonly uint[] _complexOptionType1FieldTags = new uint[] { 8, 16, 24 };

     public static ComplexOptionType1 DefaultInstance {

@@ -2460,7 +2793,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override ComplexOptionType1 DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override ComplexOptionType1 ThisMessage {

@@ -2582,11 +2915,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static ComplexOptionType1 ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private ComplexOptionType1 MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(ComplexOptionType1 prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -2596,21 +2933,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(ComplexOptionType1 cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

+      

+      private bool resultIsReadOnly;

+      private ComplexOptionType1 result;

+      

+      private ComplexOptionType1 PrepareBuilder() {

+        if (resultIsReadOnly) {

+          ComplexOptionType1 original = result;

+          result = new ComplexOptionType1();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      ComplexOptionType1 result = new ComplexOptionType1();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override ComplexOptionType1 MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new ComplexOptionType1();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -2622,12 +2986,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override ComplexOptionType1 BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        ComplexOptionType1 returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -2641,6 +3004,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(ComplexOptionType1 other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasFoo) {

           Foo = other.Foo;

         }

@@ -2660,6 +3024,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -2723,11 +3088,13 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetFoo(value); }

       }

       public Builder SetFoo(int value) {

+        PrepareBuilder();

         result.hasFoo = true;

         result.foo_ = value;

         return this;

       }

       public Builder ClearFoo() {

+        PrepareBuilder();

         result.hasFoo = false;

         result.foo_ = 0;

         return this;

@@ -2741,11 +3108,13 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetFoo2(value); }

       }

       public Builder SetFoo2(int value) {

+        PrepareBuilder();

         result.hasFoo2 = true;

         result.foo2_ = value;

         return this;

       }

       public Builder ClearFoo2() {

+        PrepareBuilder();

         result.hasFoo2 = false;

         result.foo2_ = 0;

         return this;

@@ -2759,11 +3128,13 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetFoo3(value); }

       }

       public Builder SetFoo3(int value) {

+        PrepareBuilder();

         result.hasFoo3 = true;

         result.foo3_ = value;

         return this;

       }

       public Builder ClearFoo3() {

+        PrepareBuilder();

         result.hasFoo3 = false;

         result.foo3_ = 0;

         return this;

@@ -2778,7 +3149,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class ComplexOptionType2 : pb::ExtendableMessage<ComplexOptionType2, ComplexOptionType2.Builder> {

-    private static readonly ComplexOptionType2 defaultInstance = new Builder().BuildPartial();

+    private ComplexOptionType2() { }

+    private static readonly ComplexOptionType2 defaultInstance = new ComplexOptionType2().MakeReadOnly();

     private static readonly string[] _complexOptionType2FieldNames = new string[] { "bar", "baz", "fred" };

     private static readonly uint[] _complexOptionType2FieldTags = new uint[] { 10, 16, 26 };

     public static ComplexOptionType2 DefaultInstance {

@@ -2786,7 +3158,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override ComplexOptionType2 DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override ComplexOptionType2 ThisMessage {

@@ -2810,7 +3182,8 @@ namespace Google.ProtocolBuffers.TestProtos {
       [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

       [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

       public sealed partial class ComplexOptionType4 : pb::GeneratedMessage<ComplexOptionType4, ComplexOptionType4.Builder> {

-        private static readonly ComplexOptionType4 defaultInstance = new Builder().BuildPartial();

+        private ComplexOptionType4() { }

+        private static readonly ComplexOptionType4 defaultInstance = new ComplexOptionType4().MakeReadOnly();

         private static readonly string[] _complexOptionType4FieldNames = new string[] { "waldo" };

         private static readonly uint[] _complexOptionType4FieldTags = new uint[] { 8 };

         public static ComplexOptionType4 DefaultInstance {

@@ -2818,7 +3191,7 @@ namespace Google.ProtocolBuffers.TestProtos {
         }

         

         public override ComplexOptionType4 DefaultInstanceForType {

-          get { return defaultInstance; }

+          get { return DefaultInstance; }

         }

         

         protected override ComplexOptionType4 ThisMessage {

@@ -2906,11 +3279,15 @@ namespace Google.ProtocolBuffers.TestProtos {
         public static ComplexOptionType4 ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

           return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

         }

+        private ComplexOptionType4 MakeReadOnly() {

+          return this;

+        }

+        

         public static Builder CreateBuilder() { return new Builder(); }

         public override Builder ToBuilder() { return CreateBuilder(this); }

         public override Builder CreateBuilderForType() { return new Builder(); }

         public static Builder CreateBuilder(ComplexOptionType4 prototype) {

-          return (Builder) new Builder().MergeFrom(prototype);

+          return new Builder(prototype);

         }

         

         [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -2920,21 +3297,48 @@ namespace Google.ProtocolBuffers.TestProtos {
           protected override Builder ThisBuilder {

             get { return this; }

           }

-          public Builder() {}

+          public Builder() {

+            result = DefaultInstance;

+            resultIsReadOnly = true;

+          }

+          internal Builder(ComplexOptionType4 cloneFrom) {

+            result = cloneFrom;

+            resultIsReadOnly = true;

+          }

+          

+          private bool resultIsReadOnly;

+          private ComplexOptionType4 result;

+          

+          private ComplexOptionType4 PrepareBuilder() {

+            if (resultIsReadOnly) {

+              ComplexOptionType4 original = result;

+              result = new ComplexOptionType4();

+              resultIsReadOnly = false;

+              MergeFrom(original);

+            }

+            return result;

+          }

           

-          ComplexOptionType4 result = new ComplexOptionType4();

+          public override bool IsInitialized {

+            get { return result.IsInitialized; }

+          }

           

           protected override ComplexOptionType4 MessageBeingBuilt {

-            get { return result; }

+            get { return PrepareBuilder(); }

           }

           

           public override Builder Clear() {

-            result = new ComplexOptionType4();

+            result = DefaultInstance;

+            resultIsReadOnly = true;

             return this;

           }

           

           public override Builder Clone() {

-            return new Builder().MergeFrom(result);

+            if (resultIsReadOnly) {

+              return new Builder(result);

+            } else {

+              return new Builder().MergeFrom(result);

+            }

           }

           

           public override pbd::MessageDescriptor DescriptorForType {

@@ -2946,12 +3350,11 @@ namespace Google.ProtocolBuffers.TestProtos {
           }

           

           public override ComplexOptionType4 BuildPartial() {

-            if (result == null) {

-              throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+            if (resultIsReadOnly) {

+              return result;

             }

-            ComplexOptionType4 returnMe = result;

-            result = null;

-            return returnMe;

+            resultIsReadOnly = true;

+            return result.MakeReadOnly();

           }

           

           public override Builder MergeFrom(pb::IMessage other) {

@@ -2965,6 +3368,7 @@ namespace Google.ProtocolBuffers.TestProtos {
           

           public override Builder MergeFrom(ComplexOptionType4 other) {

             if (other == global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.DefaultInstance) return this;

+            PrepareBuilder();

             if (other.HasWaldo) {

               Waldo = other.Waldo;

             }

@@ -2977,6 +3381,7 @@ namespace Google.ProtocolBuffers.TestProtos {
           }

           

           public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+            PrepareBuilder();

             pb::UnknownFieldSet.Builder unknownFields = null;

             uint tag;

             string field_name;

@@ -3032,11 +3437,13 @@ namespace Google.ProtocolBuffers.TestProtos {
             set { SetWaldo(value); }

           }

           public Builder SetWaldo(int value) {

+            PrepareBuilder();

             result.hasWaldo = true;

             result.waldo_ = value;

             return this;

           }

           public Builder ClearWaldo() {

+            PrepareBuilder();

             result.hasWaldo = false;

             result.waldo_ = 0;

             return this;

@@ -3052,12 +3459,12 @@ namespace Google.ProtocolBuffers.TestProtos {
     

     public const int BarFieldNumber = 1;

     private bool hasBar;

-    private global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1 bar_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.DefaultInstance;

+    private global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1 bar_;

     public bool HasBar {

       get { return hasBar; }

     }

     public global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1 Bar {

-      get { return bar_; }

+      get { return bar_ ?? global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.DefaultInstance; }

     }

     

     public const int BazFieldNumber = 2;

@@ -3072,12 +3479,12 @@ namespace Google.ProtocolBuffers.TestProtos {
     

     public const int FredFieldNumber = 3;

     private bool hasFred;

-    private global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4 fred_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.DefaultInstance;

+    private global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4 fred_;

     public bool HasFred {

       get { return hasFred; }

     }

     public global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4 Fred {

-      get { return fred_; }

+      get { return fred_ ?? global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.DefaultInstance; }

     }

     

     public override bool IsInitialized {

@@ -3160,11 +3567,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static ComplexOptionType2 ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private ComplexOptionType2 MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(ComplexOptionType2 prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -3174,21 +3585,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(ComplexOptionType2 cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

+      

+      private bool resultIsReadOnly;

+      private ComplexOptionType2 result;

+      

+      private ComplexOptionType2 PrepareBuilder() {

+        if (resultIsReadOnly) {

+          ComplexOptionType2 original = result;

+          result = new ComplexOptionType2();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      ComplexOptionType2 result = new ComplexOptionType2();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override ComplexOptionType2 MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new ComplexOptionType2();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -3200,12 +3638,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override ComplexOptionType2 BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        ComplexOptionType2 returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -3219,6 +3656,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(ComplexOptionType2 other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasBar) {

           MergeBar(other.Bar);

         }

@@ -3238,6 +3676,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -3312,18 +3751,21 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       public Builder SetBar(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1 value) {

         pb::ThrowHelper.ThrowIfNull(value, "value");

+        PrepareBuilder();

         result.hasBar = true;

         result.bar_ = value;

         return this;

       }

       public Builder SetBar(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.Builder builderForValue) {

         pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");

+        PrepareBuilder();

         result.hasBar = true;

         result.bar_ = builderForValue.Build();

         return this;

       }

       public Builder MergeBar(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1 value) {

         pb::ThrowHelper.ThrowIfNull(value, "value");

+        PrepareBuilder();

         if (result.hasBar &&

             result.bar_ != global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.DefaultInstance) {

             result.bar_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.CreateBuilder(result.bar_).MergeFrom(value).BuildPartial();

@@ -3334,8 +3776,9 @@ namespace Google.ProtocolBuffers.TestProtos {
         return this;

       }

       public Builder ClearBar() {

+        PrepareBuilder();

         result.hasBar = false;

-        result.bar_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType1.DefaultInstance;

+        result.bar_ = null;

         return this;

       }

       

@@ -3347,11 +3790,13 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetBaz(value); }

       }

       public Builder SetBaz(int value) {

+        PrepareBuilder();

         result.hasBaz = true;

         result.baz_ = value;

         return this;

       }

       public Builder ClearBaz() {

+        PrepareBuilder();

         result.hasBaz = false;

         result.baz_ = 0;

         return this;

@@ -3366,18 +3811,21 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       public Builder SetFred(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4 value) {

         pb::ThrowHelper.ThrowIfNull(value, "value");

+        PrepareBuilder();

         result.hasFred = true;

         result.fred_ = value;

         return this;

       }

       public Builder SetFred(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.Builder builderForValue) {

         pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");

+        PrepareBuilder();

         result.hasFred = true;

         result.fred_ = builderForValue.Build();

         return this;

       }

       public Builder MergeFred(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4 value) {

         pb::ThrowHelper.ThrowIfNull(value, "value");

+        PrepareBuilder();

         if (result.hasFred &&

             result.fred_ != global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.DefaultInstance) {

             result.fred_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.CreateBuilder(result.fred_).MergeFrom(value).BuildPartial();

@@ -3388,8 +3836,9 @@ namespace Google.ProtocolBuffers.TestProtos {
         return this;

       }

       public Builder ClearFred() {

+        PrepareBuilder();

         result.hasFred = false;

-        result.fred_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType2.Types.ComplexOptionType4.DefaultInstance;

+        result.fred_ = null;

         return this;

       }

     }

@@ -3402,7 +3851,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class ComplexOptionType3 : pb::GeneratedMessage<ComplexOptionType3, ComplexOptionType3.Builder> {

-    private static readonly ComplexOptionType3 defaultInstance = new Builder().BuildPartial();

+    private ComplexOptionType3() { }

+    private static readonly ComplexOptionType3 defaultInstance = new ComplexOptionType3().MakeReadOnly();

     private static readonly string[] _complexOptionType3FieldNames = new string[] { "complexoptiontype5", "qux" };

     private static readonly uint[] _complexOptionType3FieldTags = new uint[] { 19, 8 };

     public static ComplexOptionType3 DefaultInstance {

@@ -3410,7 +3860,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override ComplexOptionType3 DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override ComplexOptionType3 ThisMessage {

@@ -3434,7 +3884,8 @@ namespace Google.ProtocolBuffers.TestProtos {
       [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

       [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

       public sealed partial class ComplexOptionType5 : pb::GeneratedMessage<ComplexOptionType5, ComplexOptionType5.Builder> {

-        private static readonly ComplexOptionType5 defaultInstance = new Builder().BuildPartial();

+        private ComplexOptionType5() { }

+        private static readonly ComplexOptionType5 defaultInstance = new ComplexOptionType5().MakeReadOnly();

         private static readonly string[] _complexOptionType5FieldNames = new string[] { "plugh" };

         private static readonly uint[] _complexOptionType5FieldTags = new uint[] { 24 };

         public static ComplexOptionType5 DefaultInstance {

@@ -3442,7 +3893,7 @@ namespace Google.ProtocolBuffers.TestProtos {
         }

         

         public override ComplexOptionType5 DefaultInstanceForType {

-          get { return defaultInstance; }

+          get { return DefaultInstance; }

         }

         

         protected override ComplexOptionType5 ThisMessage {

@@ -3528,11 +3979,15 @@ namespace Google.ProtocolBuffers.TestProtos {
         public static ComplexOptionType5 ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

           return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

         }

+        private ComplexOptionType5 MakeReadOnly() {

+          return this;

+        }

+        

         public static Builder CreateBuilder() { return new Builder(); }

         public override Builder ToBuilder() { return CreateBuilder(this); }

         public override Builder CreateBuilderForType() { return new Builder(); }

         public static Builder CreateBuilder(ComplexOptionType5 prototype) {

-          return (Builder) new Builder().MergeFrom(prototype);

+          return new Builder(prototype);

         }

         

         [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -3542,21 +3997,48 @@ namespace Google.ProtocolBuffers.TestProtos {
           protected override Builder ThisBuilder {

             get { return this; }

           }

-          public Builder() {}

+          public Builder() {

+            result = DefaultInstance;

+            resultIsReadOnly = true;

+          }

+          internal Builder(ComplexOptionType5 cloneFrom) {

+            result = cloneFrom;

+            resultIsReadOnly = true;

+          }

+          

+          private bool resultIsReadOnly;

+          private ComplexOptionType5 result;

+          

+          private ComplexOptionType5 PrepareBuilder() {

+            if (resultIsReadOnly) {

+              ComplexOptionType5 original = result;

+              result = new ComplexOptionType5();

+              resultIsReadOnly = false;

+              MergeFrom(original);

+            }

+            return result;

+          }

           

-          ComplexOptionType5 result = new ComplexOptionType5();

+          public override bool IsInitialized {

+            get { return result.IsInitialized; }

+          }

           

           protected override ComplexOptionType5 MessageBeingBuilt {

-            get { return result; }

+            get { return PrepareBuilder(); }

           }

           

           public override Builder Clear() {

-            result = new ComplexOptionType5();

+            result = DefaultInstance;

+            resultIsReadOnly = true;

             return this;

           }

           

           public override Builder Clone() {

-            return new Builder().MergeFrom(result);

+            if (resultIsReadOnly) {

+              return new Builder(result);

+            } else {

+              return new Builder().MergeFrom(result);

+            }

           }

           

           public override pbd::MessageDescriptor DescriptorForType {

@@ -3568,12 +4050,11 @@ namespace Google.ProtocolBuffers.TestProtos {
           }

           

           public override ComplexOptionType5 BuildPartial() {

-            if (result == null) {

-              throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+            if (resultIsReadOnly) {

+              return result;

             }

-            ComplexOptionType5 returnMe = result;

-            result = null;

-            return returnMe;

+            resultIsReadOnly = true;

+            return result.MakeReadOnly();

           }

           

           public override Builder MergeFrom(pb::IMessage other) {

@@ -3587,6 +4068,7 @@ namespace Google.ProtocolBuffers.TestProtos {
           

           public override Builder MergeFrom(ComplexOptionType5 other) {

             if (other == global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.DefaultInstance) return this;

+            PrepareBuilder();

             if (other.HasPlugh) {

               Plugh = other.Plugh;

             }

@@ -3599,6 +4081,7 @@ namespace Google.ProtocolBuffers.TestProtos {
           }

           

           public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+            PrepareBuilder();

             pb::UnknownFieldSet.Builder unknownFields = null;

             uint tag;

             string field_name;

@@ -3654,11 +4137,13 @@ namespace Google.ProtocolBuffers.TestProtos {
             set { SetPlugh(value); }

           }

           public Builder SetPlugh(int value) {

+            PrepareBuilder();

             result.hasPlugh = true;

             result.plugh_ = value;

             return this;

           }

           public Builder ClearPlugh() {

+            PrepareBuilder();

             result.hasPlugh = false;

             result.plugh_ = 0;

             return this;

@@ -3684,12 +4169,12 @@ namespace Google.ProtocolBuffers.TestProtos {
     

     public const int ComplexOptionType5FieldNumber = 2;

     private bool hasComplexOptionType5;

-    private global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5 complexOptionType5_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.DefaultInstance;

+    private global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5 complexOptionType5_;

     public bool HasComplexOptionType5 {

       get { return hasComplexOptionType5; }

     }

     public global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5 ComplexOptionType5 {

-      get { return complexOptionType5_; }

+      get { return complexOptionType5_ ?? global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.DefaultInstance; }

     }

     

     public override bool IsInitialized {

@@ -3759,11 +4244,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static ComplexOptionType3 ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private ComplexOptionType3 MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(ComplexOptionType3 prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -3773,21 +4262,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(ComplexOptionType3 cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

       

-      ComplexOptionType3 result = new ComplexOptionType3();

+      private bool resultIsReadOnly;

+      private ComplexOptionType3 result;

+      

+      private ComplexOptionType3 PrepareBuilder() {

+        if (resultIsReadOnly) {

+          ComplexOptionType3 original = result;

+          result = new ComplexOptionType3();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override ComplexOptionType3 MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new ComplexOptionType3();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -3799,12 +4315,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override ComplexOptionType3 BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        ComplexOptionType3 returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -3818,6 +4333,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(ComplexOptionType3 other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasQux) {

           Qux = other.Qux;

         }

@@ -3833,6 +4349,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -3897,11 +4414,13 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetQux(value); }

       }

       public Builder SetQux(int value) {

+        PrepareBuilder();

         result.hasQux = true;

         result.qux_ = value;

         return this;

       }

       public Builder ClearQux() {

+        PrepareBuilder();

         result.hasQux = false;

         result.qux_ = 0;

         return this;

@@ -3916,18 +4435,21 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       public Builder SetComplexOptionType5(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5 value) {

         pb::ThrowHelper.ThrowIfNull(value, "value");

+        PrepareBuilder();

         result.hasComplexOptionType5 = true;

         result.complexOptionType5_ = value;

         return this;

       }

       public Builder SetComplexOptionType5(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.Builder builderForValue) {

         pb::ThrowHelper.ThrowIfNull(builderForValue, "builderForValue");

+        PrepareBuilder();

         result.hasComplexOptionType5 = true;

         result.complexOptionType5_ = builderForValue.Build();

         return this;

       }

       public Builder MergeComplexOptionType5(global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5 value) {

         pb::ThrowHelper.ThrowIfNull(value, "value");

+        PrepareBuilder();

         if (result.hasComplexOptionType5 &&

             result.complexOptionType5_ != global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.DefaultInstance) {

             result.complexOptionType5_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.CreateBuilder(result.complexOptionType5_).MergeFrom(value).BuildPartial();

@@ -3938,8 +4460,9 @@ namespace Google.ProtocolBuffers.TestProtos {
         return this;

       }

       public Builder ClearComplexOptionType5() {

+        PrepareBuilder();

         result.hasComplexOptionType5 = false;

-        result.complexOptionType5_ = global::Google.ProtocolBuffers.TestProtos.ComplexOptionType3.Types.ComplexOptionType5.DefaultInstance;

+        result.complexOptionType5_ = null;

         return this;

       }

     }

@@ -3952,7 +4475,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class ComplexOpt6 : pb::GeneratedMessage<ComplexOpt6, ComplexOpt6.Builder> {

-    private static readonly ComplexOpt6 defaultInstance = new Builder().BuildPartial();

+    private ComplexOpt6() { }

+    private static readonly ComplexOpt6 defaultInstance = new ComplexOpt6().MakeReadOnly();

     private static readonly string[] _complexOpt6FieldNames = new string[] { "xyzzy" };

     private static readonly uint[] _complexOpt6FieldTags = new uint[] { 60751608 };

     public static ComplexOpt6 DefaultInstance {

@@ -3960,7 +4484,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override ComplexOpt6 DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override ComplexOpt6 ThisMessage {

@@ -4046,11 +4570,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static ComplexOpt6 ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private ComplexOpt6 MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(ComplexOpt6 prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -4060,21 +4588,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(ComplexOpt6 cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

       

-      ComplexOpt6 result = new ComplexOpt6();

+      private bool resultIsReadOnly;

+      private ComplexOpt6 result;

+      

+      private ComplexOpt6 PrepareBuilder() {

+        if (resultIsReadOnly) {

+          ComplexOpt6 original = result;

+          result = new ComplexOpt6();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override ComplexOpt6 MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new ComplexOpt6();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -4086,12 +4641,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override ComplexOpt6 BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        ComplexOpt6 returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -4105,6 +4659,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(ComplexOpt6 other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.ComplexOpt6.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasXyzzy) {

           Xyzzy = other.Xyzzy;

         }

@@ -4117,6 +4672,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -4172,11 +4728,13 @@ namespace Google.ProtocolBuffers.TestProtos {
         set { SetXyzzy(value); }

       }

       public Builder SetXyzzy(int value) {

+        PrepareBuilder();

         result.hasXyzzy = true;

         result.xyzzy_ = value;

         return this;

       }

       public Builder ClearXyzzy() {

+        PrepareBuilder();

         result.hasXyzzy = false;

         result.xyzzy_ = 0;

         return this;

@@ -4191,7 +4749,8 @@ namespace Google.ProtocolBuffers.TestProtos {
   [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

   [global::System.CodeDom.Compiler.GeneratedCodeAttribute("ProtoGen", "2.3.0.277")]

   public sealed partial class VariousComplexOptions : pb::GeneratedMessage<VariousComplexOptions, VariousComplexOptions.Builder> {

-    private static readonly VariousComplexOptions defaultInstance = new Builder().BuildPartial();

+    private VariousComplexOptions() { }

+    private static readonly VariousComplexOptions defaultInstance = new VariousComplexOptions().MakeReadOnly();

     private static readonly string[] _variousComplexOptionsFieldNames = new string[] {  };

     private static readonly uint[] _variousComplexOptionsFieldTags = new uint[] {  };

     public static VariousComplexOptions DefaultInstance {

@@ -4199,7 +4758,7 @@ namespace Google.ProtocolBuffers.TestProtos {
     }

     

     public override VariousComplexOptions DefaultInstanceForType {

-      get { return defaultInstance; }

+      get { return DefaultInstance; }

     }

     

     protected override VariousComplexOptions ThisMessage {

@@ -4269,11 +4828,15 @@ namespace Google.ProtocolBuffers.TestProtos {
     public static VariousComplexOptions ParseFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

       return ((Builder) CreateBuilder().MergeFrom(input, extensionRegistry)).BuildParsed();

     }

+    private VariousComplexOptions MakeReadOnly() {

+      return this;

+    }

+    

     public static Builder CreateBuilder() { return new Builder(); }

     public override Builder ToBuilder() { return CreateBuilder(this); }

     public override Builder CreateBuilderForType() { return new Builder(); }

     public static Builder CreateBuilder(VariousComplexOptions prototype) {

-      return (Builder) new Builder().MergeFrom(prototype);

+      return new Builder(prototype);

     }

     

     [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

@@ -4283,21 +4846,48 @@ namespace Google.ProtocolBuffers.TestProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance;

+        resultIsReadOnly = true;

+      }

+      internal Builder(VariousComplexOptions cloneFrom) {

+        result = cloneFrom;

+        resultIsReadOnly = true;

+      }

+      

+      private bool resultIsReadOnly;

+      private VariousComplexOptions result;

+      

+      private VariousComplexOptions PrepareBuilder() {

+        if (resultIsReadOnly) {

+          VariousComplexOptions original = result;

+          result = new VariousComplexOptions();

+          resultIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      VariousComplexOptions result = new VariousComplexOptions();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override VariousComplexOptions MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new VariousComplexOptions();

+        result = DefaultInstance;

+        resultIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

-        return new Builder().MergeFrom(result);

+        if (resultIsReadOnly) {

+          return new Builder(result);

+        } else {

+          return new Builder().MergeFrom(result);

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -4309,12 +4899,11 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override VariousComplexOptions BuildPartial() {

-        if (result == null) {

-          throw new global::System.InvalidOperationException("build() has already been called on this Builder");

+        if (resultIsReadOnly) {

+          return result;

         }

-        VariousComplexOptions returnMe = result;

-        result = null;

-        return returnMe;

+        resultIsReadOnly = true;

+        return result.MakeReadOnly();

       }

       

       public override Builder MergeFrom(pb::IMessage other) {

@@ -4328,6 +4917,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       

       public override Builder MergeFrom(VariousComplexOptions other) {

         if (other == global::Google.ProtocolBuffers.TestProtos.VariousComplexOptions.DefaultInstance) return this;

+        PrepareBuilder();

         this.MergeUnknownFields(other.UnknownFields);

         return this;

       }

@@ -4337,6 +4927,7 @@ namespace Google.ProtocolBuffers.TestProtos {
       }

       

       public override Builder MergeFrom(pb::ICodedInputStream input, pb::ExtensionRegistry extensionRegistry) {

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;