First pass at implementation and testing of reusable builders.

1 files changed, 953 insertions, 219 deletions

diff --git a/src/ProtocolBuffers/DescriptorProtos/DescriptorProtoFile.cs b/src/ProtocolBuffers/DescriptorProtos/DescriptorProtoFile.cs
index 5b48cde1..631ec21f 100644
--- a/src/ProtocolBuffers/DescriptorProtos/DescriptorProtoFile.cs
+++ b/src/ProtocolBuffers/DescriptorProtos/DescriptorProtoFile.cs
@@ -336,7 +336,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(FileDescriptorSet prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -346,21 +346,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new FileDescriptorSet();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(FileDescriptorSet cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      FileDescriptorSet result;

       

-      FileDescriptorSet result = new FileDescriptorSet();

+      private FileDescriptorSet PrepareBuilder() {

+        if (builderIsReadOnly) {

+          FileDescriptorSet original = result;

+          result = new FileDescriptorSet();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override FileDescriptorSet MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new FileDescriptorSet();

+        result = DefaultInstance ?? new FileDescriptorSet();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -372,13 +399,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override FileDescriptorSet BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.file_.MakeReadOnly();

-        FileDescriptorSet returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -392,6 +418,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(FileDescriptorSet other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.FileDescriptorSet.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.file_.Count != 0) {

           base.AddRange(other.file_, result.file_);

         }

@@ -404,6 +431,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -452,7 +480,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.FileDescriptorProto> FileList {

-        get { return result.file_; }

+        get { return PrepareBuilder().file_; }

       }

       public int FileCount {

         get { return result.FileCount; }

@@ -462,29 +490,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetFile(int index, global::Google.ProtocolBuffers.DescriptorProtos.FileDescriptorProto value) {

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

+        PrepareBuilder();

         result.file_[index] = value;

         return this;

       }

       public Builder SetFile(int index, global::Google.ProtocolBuffers.DescriptorProtos.FileDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.file_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddFile(global::Google.ProtocolBuffers.DescriptorProtos.FileDescriptorProto value) {

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

+        PrepareBuilder();

         result.file_.Add(value);

         return this;

       }

       public Builder AddFile(global::Google.ProtocolBuffers.DescriptorProtos.FileDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.file_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeFile(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.FileDescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.file_);

         return this;

       }

       public Builder ClearFile() {

+        PrepareBuilder();

         result.file_.Clear();

         return this;

       }

@@ -738,7 +772,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(FileDescriptorProto prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -748,21 +782,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new FileDescriptorProto();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(FileDescriptorProto cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

       

-      FileDescriptorProto result = new FileDescriptorProto();

+      bool builderIsReadOnly;

+      FileDescriptorProto result;

+      

+      private FileDescriptorProto PrepareBuilder() {

+        if (builderIsReadOnly) {

+          FileDescriptorProto original = result;

+          result = new FileDescriptorProto();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override FileDescriptorProto MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new FileDescriptorProto();

+        result = DefaultInstance ?? new FileDescriptorProto();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -774,17 +835,16 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override FileDescriptorProto BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.dependency_.MakeReadOnly();

         result.messageType_.MakeReadOnly();

         result.enumType_.MakeReadOnly();

         result.service_.MakeReadOnly();

         result.extension_.MakeReadOnly();

-        FileDescriptorProto returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -798,6 +858,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(FileDescriptorProto other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.FileDescriptorProto.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasName) {

           Name = other.Name;

         }

@@ -831,6 +892,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -920,11 +982,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetName(string value) {

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

+        PrepareBuilder();

         result.hasName = true;

         result.name_ = value;

         return this;

       }

       public Builder ClearName() {

+        PrepareBuilder();

         result.hasName = false;

         result.name_ = "";

         return this;

@@ -939,18 +1003,20 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetPackage(string value) {

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

+        PrepareBuilder();

         result.hasPackage = true;

         result.package_ = value;

         return this;

       }

       public Builder ClearPackage() {

+        PrepareBuilder();

         result.hasPackage = false;

         result.package_ = "";

         return this;

       }

       

       public pbc::IPopsicleList<string> DependencyList {

-        get { return result.dependency_; }

+        get { return PrepareBuilder().dependency_; }

       }

       public int DependencyCount {

         get { return result.DependencyCount; }

@@ -960,25 +1026,29 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetDependency(int index, string value) {

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

+        PrepareBuilder();

         result.dependency_[index] = value;

         return this;

       }

       public Builder AddDependency(string value) {

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

+        PrepareBuilder();

         result.dependency_.Add(value);

         return this;

       }

       public Builder AddRangeDependency(scg::IEnumerable<string> values) {

+        PrepareBuilder();

         base.AddRange(values, result.dependency_);

         return this;

       }

       public Builder ClearDependency() {

+        PrepareBuilder();

         result.dependency_.Clear();

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto> MessageTypeList {

-        get { return result.messageType_; }

+        get { return PrepareBuilder().messageType_; }

       }

       public int MessageTypeCount {

         get { return result.MessageTypeCount; }

@@ -988,35 +1058,41 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetMessageType(int index, global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto value) {

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

+        PrepareBuilder();

         result.messageType_[index] = value;

         return this;

       }

       public Builder SetMessageType(int index, global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.messageType_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddMessageType(global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto value) {

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

+        PrepareBuilder();

         result.messageType_.Add(value);

         return this;

       }

       public Builder AddMessageType(global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.messageType_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeMessageType(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.messageType_);

         return this;

       }

       public Builder ClearMessageType() {

+        PrepareBuilder();

         result.messageType_.Clear();

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto> EnumTypeList {

-        get { return result.enumType_; }

+        get { return PrepareBuilder().enumType_; }

       }

       public int EnumTypeCount {

         get { return result.EnumTypeCount; }

@@ -1026,35 +1102,41 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetEnumType(int index, global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto value) {

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

+        PrepareBuilder();

         result.enumType_[index] = value;

         return this;

       }

       public Builder SetEnumType(int index, global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.enumType_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddEnumType(global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto value) {

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

+        PrepareBuilder();

         result.enumType_.Add(value);

         return this;

       }

       public Builder AddEnumType(global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.enumType_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeEnumType(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.enumType_);

         return this;

       }

       public Builder ClearEnumType() {

+        PrepareBuilder();

         result.enumType_.Clear();

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.ServiceDescriptorProto> ServiceList {

-        get { return result.service_; }

+        get { return PrepareBuilder().service_; }

       }

       public int ServiceCount {

         get { return result.ServiceCount; }

@@ -1064,35 +1146,41 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetService(int index, global::Google.ProtocolBuffers.DescriptorProtos.ServiceDescriptorProto value) {

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

+        PrepareBuilder();

         result.service_[index] = value;

         return this;

       }

       public Builder SetService(int index, global::Google.ProtocolBuffers.DescriptorProtos.ServiceDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.service_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddService(global::Google.ProtocolBuffers.DescriptorProtos.ServiceDescriptorProto value) {

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

+        PrepareBuilder();

         result.service_.Add(value);

         return this;

       }

       public Builder AddService(global::Google.ProtocolBuffers.DescriptorProtos.ServiceDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.service_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeService(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.ServiceDescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.service_);

         return this;

       }

       public Builder ClearService() {

+        PrepareBuilder();

         result.service_.Clear();

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto> ExtensionList {

-        get { return result.extension_; }

+        get { return PrepareBuilder().extension_; }

       }

       public int ExtensionCount {

         get { return result.ExtensionCount; }

@@ -1102,29 +1190,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetExtension(int index, global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto value) {

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

+        PrepareBuilder();

         result.extension_[index] = value;

         return this;

       }

       public Builder SetExtension(int index, global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.extension_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddExtension(global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto value) {

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

+        PrepareBuilder();

         result.extension_.Add(value);

         return this;

       }

       public Builder AddExtension(global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.extension_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeExtension(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.extension_);

         return this;

       }

       public Builder ClearExtension() {

+        PrepareBuilder();

         result.extension_.Clear();

         return this;

       }

@@ -1138,18 +1232,21 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.FileOptions value) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = value;

         return this;

       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.FileOptions.Builder builderForValue) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = builderForValue.Build();

         return this;

       }

       public Builder MergeOptions(global::Google.ProtocolBuffers.DescriptorProtos.FileOptions value) {

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

+        PrepareBuilder();

         if (result.hasOptions &&

             result.options_ != global::Google.ProtocolBuffers.DescriptorProtos.FileOptions.DefaultInstance) {

             result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.FileOptions.CreateBuilder(result.options_).MergeFrom(value).BuildPartial();

@@ -1160,6 +1257,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         return this;

       }

       public Builder ClearOptions() {

+        PrepareBuilder();

         result.hasOptions = false;

         result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.FileOptions.DefaultInstance;

         return this;

@@ -1320,7 +1418,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         public override Builder ToBuilder() { return CreateBuilder(this); }

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

         public static Builder CreateBuilder(ExtensionRange prototype) {

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

+          return new Builder(prototype);

         }

         

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

@@ -1330,21 +1428,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
           protected override Builder ThisBuilder {

             get { return this; }

           }

-          public Builder() {}

+          public Builder() {

+            result = DefaultInstance ?? new ExtensionRange();

+            builderIsReadOnly = result == DefaultInstance;

+          }

+          internal Builder(ExtensionRange cloneFrom) {

+            result = cloneFrom;

+            builderIsReadOnly = true;

+          }

           

-          ExtensionRange result = new ExtensionRange();

+          bool builderIsReadOnly;

+          ExtensionRange result;

+          

+          private ExtensionRange PrepareBuilder() {

+            if (builderIsReadOnly) {

+              ExtensionRange original = result;

+              result = new ExtensionRange();

+              builderIsReadOnly = false;

+              MergeFrom(original);

+            }

+            return result;

+          }

+          

+          public override bool IsInitialized {

+            get { return result.IsInitialized; }

+          }

           

           protected override ExtensionRange MessageBeingBuilt {

-            get { return result; }

+            get { return PrepareBuilder(); }

           }

           

           public override Builder Clear() {

-            result = new ExtensionRange();

+            result = DefaultInstance ?? new ExtensionRange();

+            builderIsReadOnly = true;

             return this;

           }

           

           public override Builder Clone() {

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

+            if (builderIsReadOnly) {

+              return new Builder(result);

+            } else {

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

+            }

           }

           

           public override pbd::MessageDescriptor DescriptorForType {

@@ -1356,12 +1481,11 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
           }

           

           public override ExtensionRange BuildPartial() {

-            if (result == null) {

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

+            if (builderIsReadOnly) {

+              return result;

             }

-            ExtensionRange returnMe = result;

-            result = null;

-            return returnMe;

+            builderIsReadOnly = true;

+            return result;

           }

           

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

@@ -1375,6 +1499,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
           

           public override Builder MergeFrom(ExtensionRange other) {

             if (other == global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Types.ExtensionRange.DefaultInstance) return this;

+            PrepareBuilder();

             if (other.HasStart) {

               Start = other.Start;

             }

@@ -1390,6 +1515,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
           }

           

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

+            PrepareBuilder();

             pb::UnknownFieldSet.Builder unknownFields = null;

             uint tag;

             string field_name;

@@ -1449,11 +1575,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
             set { SetStart(value); }

           }

           public Builder SetStart(int value) {

+            PrepareBuilder();

             result.hasStart = true;

             result.start_ = value;

             return this;

           }

           public Builder ClearStart() {

+            PrepareBuilder();

             result.hasStart = false;

             result.start_ = 0;

             return this;

@@ -1467,11 +1595,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
             set { SetEnd(value); }

           }

           public Builder SetEnd(int value) {

+            PrepareBuilder();

             result.hasEnd = true;

             result.end_ = value;

             return this;

           }

           public Builder ClearEnd() {

+            PrepareBuilder();

             result.hasEnd = false;

             result.end_ = 0;

             return this;

@@ -1681,7 +1811,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(DescriptorProto prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -1691,21 +1821,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new DescriptorProto();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(DescriptorProto cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      DescriptorProto result;

+      

+      private DescriptorProto PrepareBuilder() {

+        if (builderIsReadOnly) {

+          DescriptorProto original = result;

+          result = new DescriptorProto();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      DescriptorProto result = new DescriptorProto();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override DescriptorProto MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new DescriptorProto();

+        result = DefaultInstance ?? new DescriptorProto();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -1717,17 +1874,16 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override DescriptorProto BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.field_.MakeReadOnly();

         result.extension_.MakeReadOnly();

         result.nestedType_.MakeReadOnly();

         result.enumType_.MakeReadOnly();

         result.extensionRange_.MakeReadOnly();

-        DescriptorProto returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -1741,6 +1897,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(DescriptorProto other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasName) {

           Name = other.Name;

         }

@@ -1771,6 +1928,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -1856,18 +2014,20 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetName(string value) {

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

+        PrepareBuilder();

         result.hasName = true;

         result.name_ = value;

         return this;

       }

       public Builder ClearName() {

+        PrepareBuilder();

         result.hasName = false;

         result.name_ = "";

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto> FieldList {

-        get { return result.field_; }

+        get { return PrepareBuilder().field_; }

       }

       public int FieldCount {

         get { return result.FieldCount; }

@@ -1877,35 +2037,41 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetField(int index, global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto value) {

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

+        PrepareBuilder();

         result.field_[index] = value;

         return this;

       }

       public Builder SetField(int index, global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.field_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddField(global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto value) {

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

+        PrepareBuilder();

         result.field_.Add(value);

         return this;

       }

       public Builder AddField(global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.field_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeField(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.field_);

         return this;

       }

       public Builder ClearField() {

+        PrepareBuilder();

         result.field_.Clear();

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto> ExtensionList {

-        get { return result.extension_; }

+        get { return PrepareBuilder().extension_; }

       }

       public int ExtensionCount {

         get { return result.ExtensionCount; }

@@ -1915,35 +2081,41 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetExtension(int index, global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto value) {

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

+        PrepareBuilder();

         result.extension_[index] = value;

         return this;

       }

       public Builder SetExtension(int index, global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.extension_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddExtension(global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto value) {

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

+        PrepareBuilder();

         result.extension_.Add(value);

         return this;

       }

       public Builder AddExtension(global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.extension_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeExtension(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.extension_);

         return this;

       }

       public Builder ClearExtension() {

+        PrepareBuilder();

         result.extension_.Clear();

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto> NestedTypeList {

-        get { return result.nestedType_; }

+        get { return PrepareBuilder().nestedType_; }

       }

       public int NestedTypeCount {

         get { return result.NestedTypeCount; }

@@ -1953,35 +2125,41 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetNestedType(int index, global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto value) {

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

+        PrepareBuilder();

         result.nestedType_[index] = value;

         return this;

       }

       public Builder SetNestedType(int index, global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.nestedType_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddNestedType(global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto value) {

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

+        PrepareBuilder();

         result.nestedType_.Add(value);

         return this;

       }

       public Builder AddNestedType(global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.nestedType_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeNestedType(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.nestedType_);

         return this;

       }

       public Builder ClearNestedType() {

+        PrepareBuilder();

         result.nestedType_.Clear();

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto> EnumTypeList {

-        get { return result.enumType_; }

+        get { return PrepareBuilder().enumType_; }

       }

       public int EnumTypeCount {

         get { return result.EnumTypeCount; }

@@ -1991,35 +2169,41 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetEnumType(int index, global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto value) {

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

+        PrepareBuilder();

         result.enumType_[index] = value;

         return this;

       }

       public Builder SetEnumType(int index, global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.enumType_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddEnumType(global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto value) {

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

+        PrepareBuilder();

         result.enumType_.Add(value);

         return this;

       }

       public Builder AddEnumType(global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.enumType_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeEnumType(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.enumType_);

         return this;

       }

       public Builder ClearEnumType() {

+        PrepareBuilder();

         result.enumType_.Clear();

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Types.ExtensionRange> ExtensionRangeList {

-        get { return result.extensionRange_; }

+        get { return PrepareBuilder().extensionRange_; }

       }

       public int ExtensionRangeCount {

         get { return result.ExtensionRangeCount; }

@@ -2029,29 +2213,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetExtensionRange(int index, global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Types.ExtensionRange value) {

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

+        PrepareBuilder();

         result.extensionRange_[index] = value;

         return this;

       }

       public Builder SetExtensionRange(int index, global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Types.ExtensionRange.Builder builderForValue) {

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

+        PrepareBuilder();

         result.extensionRange_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddExtensionRange(global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Types.ExtensionRange value) {

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

+        PrepareBuilder();

         result.extensionRange_.Add(value);

         return this;

       }

       public Builder AddExtensionRange(global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Types.ExtensionRange.Builder builderForValue) {

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

+        PrepareBuilder();

         result.extensionRange_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeExtensionRange(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.DescriptorProto.Types.ExtensionRange> values) {

+        PrepareBuilder();

         base.AddRange(values, result.extensionRange_);

         return this;

       }

       public Builder ClearExtensionRange() {

+        PrepareBuilder();

         result.extensionRange_.Clear();

         return this;

       }

@@ -2065,18 +2255,21 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.MessageOptions value) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = value;

         return this;

       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.MessageOptions.Builder builderForValue) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = builderForValue.Build();

         return this;

       }

       public Builder MergeOptions(global::Google.ProtocolBuffers.DescriptorProtos.MessageOptions value) {

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

+        PrepareBuilder();

         if (result.hasOptions &&

             result.options_ != global::Google.ProtocolBuffers.DescriptorProtos.MessageOptions.DefaultInstance) {

             result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.MessageOptions.CreateBuilder(result.options_).MergeFrom(value).BuildPartial();

@@ -2087,6 +2280,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         return this;

       }

       public Builder ClearOptions() {

+        PrepareBuilder();

         result.hasOptions = false;

         result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.MessageOptions.DefaultInstance;

         return this;

@@ -2353,7 +2547,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(FieldDescriptorProto prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -2363,21 +2557,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new FieldDescriptorProto();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(FieldDescriptorProto cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      FieldDescriptorProto result;

       

-      FieldDescriptorProto result = new FieldDescriptorProto();

+      private FieldDescriptorProto PrepareBuilder() {

+        if (builderIsReadOnly) {

+          FieldDescriptorProto original = result;

+          result = new FieldDescriptorProto();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override FieldDescriptorProto MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new FieldDescriptorProto();

+        result = DefaultInstance ?? new FieldDescriptorProto();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -2389,12 +2610,11 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override FieldDescriptorProto BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

-        FieldDescriptorProto returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -2408,6 +2628,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(FieldDescriptorProto other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasName) {

           Name = other.Name;

         }

@@ -2441,6 +2662,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -2546,11 +2768,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetName(string value) {

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

+        PrepareBuilder();

         result.hasName = true;

         result.name_ = value;

         return this;

       }

       public Builder ClearName() {

+        PrepareBuilder();

         result.hasName = false;

         result.name_ = "";

         return this;

@@ -2564,11 +2788,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetNumber(value); }

       }

       public Builder SetNumber(int value) {

+        PrepareBuilder();

         result.hasNumber = true;

         result.number_ = value;

         return this;

       }

       public Builder ClearNumber() {

+        PrepareBuilder();

         result.hasNumber = false;

         result.number_ = 0;

         return this;

@@ -2582,11 +2808,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetLabel(value); }

       }

       public Builder SetLabel(global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Types.Label value) {

+        PrepareBuilder();

         result.hasLabel = true;

         result.label_ = value;

         return this;

       }

       public Builder ClearLabel() {

+        PrepareBuilder();

         result.hasLabel = false;

         result.label_ = global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Types.Label.LABEL_OPTIONAL;

         return this;

@@ -2600,11 +2828,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetType(value); }

       }

       public Builder SetType(global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Types.Type value) {

+        PrepareBuilder();

         result.hasType = true;

         result.type_ = value;

         return this;

       }

       public Builder ClearType() {

+        PrepareBuilder();

         result.hasType = false;

         result.type_ = global::Google.ProtocolBuffers.DescriptorProtos.FieldDescriptorProto.Types.Type.TYPE_DOUBLE;

         return this;

@@ -2619,11 +2849,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetTypeName(string value) {

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

+        PrepareBuilder();

         result.hasTypeName = true;

         result.typeName_ = value;

         return this;

       }

       public Builder ClearTypeName() {

+        PrepareBuilder();

         result.hasTypeName = false;

         result.typeName_ = "";

         return this;

@@ -2638,11 +2870,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetExtendee(string value) {

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

+        PrepareBuilder();

         result.hasExtendee = true;

         result.extendee_ = value;

         return this;

       }

       public Builder ClearExtendee() {

+        PrepareBuilder();

         result.hasExtendee = false;

         result.extendee_ = "";

         return this;

@@ -2657,11 +2891,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetDefaultValue(string value) {

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

+        PrepareBuilder();

         result.hasDefaultValue = true;

         result.defaultValue_ = value;

         return this;

       }

       public Builder ClearDefaultValue() {

+        PrepareBuilder();

         result.hasDefaultValue = false;

         result.defaultValue_ = "";

         return this;

@@ -2676,18 +2912,21 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.FieldOptions value) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = value;

         return this;

       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.FieldOptions.Builder builderForValue) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = builderForValue.Build();

         return this;

       }

       public Builder MergeOptions(global::Google.ProtocolBuffers.DescriptorProtos.FieldOptions value) {

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

+        PrepareBuilder();

         if (result.hasOptions &&

             result.options_ != global::Google.ProtocolBuffers.DescriptorProtos.FieldOptions.DefaultInstance) {

             result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.FieldOptions.CreateBuilder(result.options_).MergeFrom(value).BuildPartial();

@@ -2698,6 +2937,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         return this;

       }

       public Builder ClearOptions() {

+        PrepareBuilder();

         result.hasOptions = false;

         result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.FieldOptions.DefaultInstance;

         return this;

@@ -2850,7 +3090,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(EnumDescriptorProto prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -2860,21 +3100,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new EnumDescriptorProto();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(EnumDescriptorProto cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      EnumDescriptorProto result;

+      

+      private EnumDescriptorProto PrepareBuilder() {

+        if (builderIsReadOnly) {

+          EnumDescriptorProto original = result;

+          result = new EnumDescriptorProto();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      EnumDescriptorProto result = new EnumDescriptorProto();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override EnumDescriptorProto MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new EnumDescriptorProto();

+        result = DefaultInstance ?? new EnumDescriptorProto();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -2886,13 +3153,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override EnumDescriptorProto BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.value_.MakeReadOnly();

-        EnumDescriptorProto returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -2906,6 +3172,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(EnumDescriptorProto other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.EnumDescriptorProto.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasName) {

           Name = other.Name;

         }

@@ -2924,6 +3191,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -2993,18 +3261,20 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetName(string value) {

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

+        PrepareBuilder();

         result.hasName = true;

         result.name_ = value;

         return this;

       }

       public Builder ClearName() {

+        PrepareBuilder();

         result.hasName = false;

         result.name_ = "";

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.EnumValueDescriptorProto> ValueList {

-        get { return result.value_; }

+        get { return PrepareBuilder().value_; }

       }

       public int ValueCount {

         get { return result.ValueCount; }

@@ -3014,29 +3284,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetValue(int index, global::Google.ProtocolBuffers.DescriptorProtos.EnumValueDescriptorProto value) {

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

+        PrepareBuilder();

         result.value_[index] = value;

         return this;

       }

       public Builder SetValue(int index, global::Google.ProtocolBuffers.DescriptorProtos.EnumValueDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.value_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddValue(global::Google.ProtocolBuffers.DescriptorProtos.EnumValueDescriptorProto value) {

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

+        PrepareBuilder();

         result.value_.Add(value);

         return this;

       }

       public Builder AddValue(global::Google.ProtocolBuffers.DescriptorProtos.EnumValueDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.value_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeValue(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.EnumValueDescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.value_);

         return this;

       }

       public Builder ClearValue() {

+        PrepareBuilder();

         result.value_.Clear();

         return this;

       }

@@ -3050,18 +3326,21 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.EnumOptions value) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = value;

         return this;

       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.EnumOptions.Builder builderForValue) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = builderForValue.Build();

         return this;

       }

       public Builder MergeOptions(global::Google.ProtocolBuffers.DescriptorProtos.EnumOptions value) {

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

+        PrepareBuilder();

         if (result.hasOptions &&

             result.options_ != global::Google.ProtocolBuffers.DescriptorProtos.EnumOptions.DefaultInstance) {

             result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.EnumOptions.CreateBuilder(result.options_).MergeFrom(value).BuildPartial();

@@ -3072,6 +3351,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         return this;

       }

       public Builder ClearOptions() {

+        PrepareBuilder();

         result.hasOptions = false;

         result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.EnumOptions.DefaultInstance;

         return this;

@@ -3219,7 +3499,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(EnumValueDescriptorProto prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -3229,21 +3509,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new EnumValueDescriptorProto();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(EnumValueDescriptorProto cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

       

-      EnumValueDescriptorProto result = new EnumValueDescriptorProto();

+      bool builderIsReadOnly;

+      EnumValueDescriptorProto result;

+      

+      private EnumValueDescriptorProto PrepareBuilder() {

+        if (builderIsReadOnly) {

+          EnumValueDescriptorProto original = result;

+          result = new EnumValueDescriptorProto();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override EnumValueDescriptorProto MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new EnumValueDescriptorProto();

+        result = DefaultInstance ?? new EnumValueDescriptorProto();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -3255,12 +3562,11 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override EnumValueDescriptorProto BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

-        EnumValueDescriptorProto returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -3274,6 +3580,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(EnumValueDescriptorProto other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.EnumValueDescriptorProto.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasName) {

           Name = other.Name;

         }

@@ -3292,6 +3599,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -3361,11 +3669,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetName(string value) {

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

+        PrepareBuilder();

         result.hasName = true;

         result.name_ = value;

         return this;

       }

       public Builder ClearName() {

+        PrepareBuilder();

         result.hasName = false;

         result.name_ = "";

         return this;

@@ -3379,11 +3689,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetNumber(value); }

       }

       public Builder SetNumber(int value) {

+        PrepareBuilder();

         result.hasNumber = true;

         result.number_ = value;

         return this;

       }

       public Builder ClearNumber() {

+        PrepareBuilder();

         result.hasNumber = false;

         result.number_ = 0;

         return this;

@@ -3398,18 +3710,21 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.EnumValueOptions value) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = value;

         return this;

       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.EnumValueOptions.Builder builderForValue) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = builderForValue.Build();

         return this;

       }

       public Builder MergeOptions(global::Google.ProtocolBuffers.DescriptorProtos.EnumValueOptions value) {

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

+        PrepareBuilder();

         if (result.hasOptions &&

             result.options_ != global::Google.ProtocolBuffers.DescriptorProtos.EnumValueOptions.DefaultInstance) {

             result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.EnumValueOptions.CreateBuilder(result.options_).MergeFrom(value).BuildPartial();

@@ -3420,6 +3735,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         return this;

       }

       public Builder ClearOptions() {

+        PrepareBuilder();

         result.hasOptions = false;

         result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.EnumValueOptions.DefaultInstance;

         return this;

@@ -3572,7 +3888,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(ServiceDescriptorProto prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -3582,21 +3898,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new ServiceDescriptorProto();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(ServiceDescriptorProto cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      ServiceDescriptorProto result;

+      

+      private ServiceDescriptorProto PrepareBuilder() {

+        if (builderIsReadOnly) {

+          ServiceDescriptorProto original = result;

+          result = new ServiceDescriptorProto();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      ServiceDescriptorProto result = new ServiceDescriptorProto();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override ServiceDescriptorProto MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new ServiceDescriptorProto();

+        result = DefaultInstance ?? new ServiceDescriptorProto();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -3608,13 +3951,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override ServiceDescriptorProto BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.method_.MakeReadOnly();

-        ServiceDescriptorProto returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -3628,6 +3970,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(ServiceDescriptorProto other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.ServiceDescriptorProto.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasName) {

           Name = other.Name;

         }

@@ -3646,6 +3989,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -3715,18 +4059,20 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetName(string value) {

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

+        PrepareBuilder();

         result.hasName = true;

         result.name_ = value;

         return this;

       }

       public Builder ClearName() {

+        PrepareBuilder();

         result.hasName = false;

         result.name_ = "";

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.MethodDescriptorProto> MethodList {

-        get { return result.method_; }

+        get { return PrepareBuilder().method_; }

       }

       public int MethodCount {

         get { return result.MethodCount; }

@@ -3736,29 +4082,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetMethod(int index, global::Google.ProtocolBuffers.DescriptorProtos.MethodDescriptorProto value) {

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

+        PrepareBuilder();

         result.method_[index] = value;

         return this;

       }

       public Builder SetMethod(int index, global::Google.ProtocolBuffers.DescriptorProtos.MethodDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.method_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddMethod(global::Google.ProtocolBuffers.DescriptorProtos.MethodDescriptorProto value) {

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

+        PrepareBuilder();

         result.method_.Add(value);

         return this;

       }

       public Builder AddMethod(global::Google.ProtocolBuffers.DescriptorProtos.MethodDescriptorProto.Builder builderForValue) {

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

+        PrepareBuilder();

         result.method_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeMethod(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.MethodDescriptorProto> values) {

+        PrepareBuilder();

         base.AddRange(values, result.method_);

         return this;

       }

       public Builder ClearMethod() {

+        PrepareBuilder();

         result.method_.Clear();

         return this;

       }

@@ -3772,18 +4124,21 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.ServiceOptions value) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = value;

         return this;

       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.ServiceOptions.Builder builderForValue) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = builderForValue.Build();

         return this;

       }

       public Builder MergeOptions(global::Google.ProtocolBuffers.DescriptorProtos.ServiceOptions value) {

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

+        PrepareBuilder();

         if (result.hasOptions &&

             result.options_ != global::Google.ProtocolBuffers.DescriptorProtos.ServiceOptions.DefaultInstance) {

             result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.ServiceOptions.CreateBuilder(result.options_).MergeFrom(value).BuildPartial();

@@ -3794,6 +4149,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         return this;

       }

       public Builder ClearOptions() {

+        PrepareBuilder();

         result.hasOptions = false;

         result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.ServiceOptions.DefaultInstance;

         return this;

@@ -3957,7 +4313,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(MethodDescriptorProto prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -3967,21 +4323,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new MethodDescriptorProto();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(MethodDescriptorProto cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      MethodDescriptorProto result;

+      

+      private MethodDescriptorProto PrepareBuilder() {

+        if (builderIsReadOnly) {

+          MethodDescriptorProto original = result;

+          result = new MethodDescriptorProto();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      MethodDescriptorProto result = new MethodDescriptorProto();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override MethodDescriptorProto MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new MethodDescriptorProto();

+        result = DefaultInstance ?? new MethodDescriptorProto();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -3993,12 +4376,11 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override MethodDescriptorProto BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

-        MethodDescriptorProto returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -4012,6 +4394,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(MethodDescriptorProto other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.MethodDescriptorProto.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasName) {

           Name = other.Name;

         }

@@ -4033,6 +4416,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -4106,11 +4490,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetName(string value) {

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

+        PrepareBuilder();

         result.hasName = true;

         result.name_ = value;

         return this;

       }

       public Builder ClearName() {

+        PrepareBuilder();

         result.hasName = false;

         result.name_ = "";

         return this;

@@ -4125,11 +4511,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetInputType(string value) {

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

+        PrepareBuilder();

         result.hasInputType = true;

         result.inputType_ = value;

         return this;

       }

       public Builder ClearInputType() {

+        PrepareBuilder();

         result.hasInputType = false;

         result.inputType_ = "";

         return this;

@@ -4144,11 +4532,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetOutputType(string value) {

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

+        PrepareBuilder();

         result.hasOutputType = true;

         result.outputType_ = value;

         return this;

       }

       public Builder ClearOutputType() {

+        PrepareBuilder();

         result.hasOutputType = false;

         result.outputType_ = "";

         return this;

@@ -4163,18 +4553,21 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.MethodOptions value) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = value;

         return this;

       }

       public Builder SetOptions(global::Google.ProtocolBuffers.DescriptorProtos.MethodOptions.Builder builderForValue) {

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

+        PrepareBuilder();

         result.hasOptions = true;

         result.options_ = builderForValue.Build();

         return this;

       }

       public Builder MergeOptions(global::Google.ProtocolBuffers.DescriptorProtos.MethodOptions value) {

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

+        PrepareBuilder();

         if (result.hasOptions &&

             result.options_ != global::Google.ProtocolBuffers.DescriptorProtos.MethodOptions.DefaultInstance) {

             result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.MethodOptions.CreateBuilder(result.options_).MergeFrom(value).BuildPartial();

@@ -4185,6 +4578,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         return this;

       }

       public Builder ClearOptions() {

+        PrepareBuilder();

         result.hasOptions = false;

         result.options_ = global::Google.ProtocolBuffers.DescriptorProtos.MethodOptions.DefaultInstance;

         return this;

@@ -4434,7 +4828,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(FileOptions prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -4444,21 +4838,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new FileOptions();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(FileOptions cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      FileOptions result;

       

-      FileOptions result = new FileOptions();

+      private FileOptions PrepareBuilder() {

+        if (builderIsReadOnly) {

+          FileOptions original = result;

+          result = new FileOptions();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override FileOptions MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new FileOptions();

+        result = DefaultInstance ?? new FileOptions();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -4470,13 +4891,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override FileOptions BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.uninterpretedOption_.MakeReadOnly();

-        FileOptions returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -4490,6 +4910,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(FileOptions other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.FileOptions.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasJavaPackage) {

           JavaPackage = other.JavaPackage;

         }

@@ -4524,6 +4945,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -4616,11 +5038,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetJavaPackage(string value) {

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

+        PrepareBuilder();

         result.hasJavaPackage = true;

         result.javaPackage_ = value;

         return this;

       }

       public Builder ClearJavaPackage() {

+        PrepareBuilder();

         result.hasJavaPackage = false;

         result.javaPackage_ = "";

         return this;

@@ -4635,11 +5059,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetJavaOuterClassname(string value) {

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

+        PrepareBuilder();

         result.hasJavaOuterClassname = true;

         result.javaOuterClassname_ = value;

         return this;

       }

       public Builder ClearJavaOuterClassname() {

+        PrepareBuilder();

         result.hasJavaOuterClassname = false;

         result.javaOuterClassname_ = "";

         return this;

@@ -4653,11 +5079,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetJavaMultipleFiles(value); }

       }

       public Builder SetJavaMultipleFiles(bool value) {

+        PrepareBuilder();

         result.hasJavaMultipleFiles = true;

         result.javaMultipleFiles_ = value;

         return this;

       }

       public Builder ClearJavaMultipleFiles() {

+        PrepareBuilder();

         result.hasJavaMultipleFiles = false;

         result.javaMultipleFiles_ = false;

         return this;

@@ -4671,11 +5099,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetOptimizeFor(value); }

       }

       public Builder SetOptimizeFor(global::Google.ProtocolBuffers.DescriptorProtos.FileOptions.Types.OptimizeMode value) {

+        PrepareBuilder();

         result.hasOptimizeFor = true;

         result.optimizeFor_ = value;

         return this;

       }

       public Builder ClearOptimizeFor() {

+        PrepareBuilder();

         result.hasOptimizeFor = false;

         result.optimizeFor_ = global::Google.ProtocolBuffers.DescriptorProtos.FileOptions.Types.OptimizeMode.SPEED;

         return this;

@@ -4689,11 +5119,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetCcGenericServices(value); }

       }

       public Builder SetCcGenericServices(bool value) {

+        PrepareBuilder();

         result.hasCcGenericServices = true;

         result.ccGenericServices_ = value;

         return this;

       }

       public Builder ClearCcGenericServices() {

+        PrepareBuilder();

         result.hasCcGenericServices = false;

         result.ccGenericServices_ = true;

         return this;

@@ -4707,11 +5139,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetJavaGenericServices(value); }

       }

       public Builder SetJavaGenericServices(bool value) {

+        PrepareBuilder();

         result.hasJavaGenericServices = true;

         result.javaGenericServices_ = value;

         return this;

       }

       public Builder ClearJavaGenericServices() {

+        PrepareBuilder();

         result.hasJavaGenericServices = false;

         result.javaGenericServices_ = true;

         return this;

@@ -4725,18 +5159,20 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetPyGenericServices(value); }

       }

       public Builder SetPyGenericServices(bool value) {

+        PrepareBuilder();

         result.hasPyGenericServices = true;

         result.pyGenericServices_ = value;

         return this;

       }

       public Builder ClearPyGenericServices() {

+        PrepareBuilder();

         result.hasPyGenericServices = false;

         result.pyGenericServices_ = true;

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> UninterpretedOptionList {

-        get { return result.uninterpretedOption_; }

+        get { return PrepareBuilder().uninterpretedOption_; }

       }

       public int UninterpretedOptionCount {

         get { return result.UninterpretedOptionCount; }

@@ -4746,29 +5182,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = value;

         return this;

       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(value);

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeUninterpretedOption(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> values) {

+        PrepareBuilder();

         base.AddRange(values, result.uninterpretedOption_);

         return this;

       }

       public Builder ClearUninterpretedOption() {

+        PrepareBuilder();

         result.uninterpretedOption_.Clear();

         return this;

       }

@@ -4921,7 +5363,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(MessageOptions prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -4931,21 +5373,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new MessageOptions();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(MessageOptions cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

       

-      MessageOptions result = new MessageOptions();

+      bool builderIsReadOnly;

+      MessageOptions result;

+      

+      private MessageOptions PrepareBuilder() {

+        if (builderIsReadOnly) {

+          MessageOptions original = result;

+          result = new MessageOptions();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override MessageOptions MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new MessageOptions();

+        result = DefaultInstance ?? new MessageOptions();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -4957,13 +5426,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override MessageOptions BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.uninterpretedOption_.MakeReadOnly();

-        MessageOptions returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -4977,6 +5445,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(MessageOptions other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.MessageOptions.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasMessageSetWireFormat) {

           MessageSetWireFormat = other.MessageSetWireFormat;

         }

@@ -4996,6 +5465,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -5059,11 +5529,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetMessageSetWireFormat(value); }

       }

       public Builder SetMessageSetWireFormat(bool value) {

+        PrepareBuilder();

         result.hasMessageSetWireFormat = true;

         result.messageSetWireFormat_ = value;

         return this;

       }

       public Builder ClearMessageSetWireFormat() {

+        PrepareBuilder();

         result.hasMessageSetWireFormat = false;

         result.messageSetWireFormat_ = false;

         return this;

@@ -5077,18 +5549,20 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetNoStandardDescriptorAccessor(value); }

       }

       public Builder SetNoStandardDescriptorAccessor(bool value) {

+        PrepareBuilder();

         result.hasNoStandardDescriptorAccessor = true;

         result.noStandardDescriptorAccessor_ = value;

         return this;

       }

       public Builder ClearNoStandardDescriptorAccessor() {

+        PrepareBuilder();

         result.hasNoStandardDescriptorAccessor = false;

         result.noStandardDescriptorAccessor_ = false;

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> UninterpretedOptionList {

-        get { return result.uninterpretedOption_; }

+        get { return PrepareBuilder().uninterpretedOption_; }

       }

       public int UninterpretedOptionCount {

         get { return result.UninterpretedOptionCount; }

@@ -5098,29 +5572,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = value;

         return this;

       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(value);

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeUninterpretedOption(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> values) {

+        PrepareBuilder();

         base.AddRange(values, result.uninterpretedOption_);

         return this;

       }

       public Builder ClearUninterpretedOption() {

+        PrepareBuilder();

         result.uninterpretedOption_.Clear();

         return this;

       }

@@ -5321,7 +5801,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(FieldOptions prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -5331,21 +5811,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new FieldOptions();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(FieldOptions cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

       

-      FieldOptions result = new FieldOptions();

+      bool builderIsReadOnly;

+      FieldOptions result;

+      

+      private FieldOptions PrepareBuilder() {

+        if (builderIsReadOnly) {

+          FieldOptions original = result;

+          result = new FieldOptions();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override FieldOptions MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new FieldOptions();

+        result = DefaultInstance ?? new FieldOptions();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -5357,13 +5864,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override FieldOptions BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.uninterpretedOption_.MakeReadOnly();

-        FieldOptions returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -5377,6 +5883,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(FieldOptions other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.FieldOptions.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.HasCtype) {

           Ctype = other.Ctype;

         }

@@ -5402,6 +5909,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -5481,11 +5989,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetCtype(value); }

       }

       public Builder SetCtype(global::Google.ProtocolBuffers.DescriptorProtos.FieldOptions.Types.CType value) {

+        PrepareBuilder();

         result.hasCtype = true;

         result.ctype_ = value;

         return this;

       }

       public Builder ClearCtype() {

+        PrepareBuilder();

         result.hasCtype = false;

         result.ctype_ = global::Google.ProtocolBuffers.DescriptorProtos.FieldOptions.Types.CType.STRING;

         return this;

@@ -5499,11 +6009,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetPacked(value); }

       }

       public Builder SetPacked(bool value) {

+        PrepareBuilder();

         result.hasPacked = true;

         result.packed_ = value;

         return this;

       }

       public Builder ClearPacked() {

+        PrepareBuilder();

         result.hasPacked = false;

         result.packed_ = false;

         return this;

@@ -5517,11 +6029,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetDeprecated(value); }

       }

       public Builder SetDeprecated(bool value) {

+        PrepareBuilder();

         result.hasDeprecated = true;

         result.deprecated_ = value;

         return this;

       }

       public Builder ClearDeprecated() {

+        PrepareBuilder();

         result.hasDeprecated = false;

         result.deprecated_ = false;

         return this;

@@ -5536,18 +6050,20 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetExperimentalMapKey(string value) {

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

+        PrepareBuilder();

         result.hasExperimentalMapKey = true;

         result.experimentalMapKey_ = value;

         return this;

       }

       public Builder ClearExperimentalMapKey() {

+        PrepareBuilder();

         result.hasExperimentalMapKey = false;

         result.experimentalMapKey_ = "";

         return this;

       }

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> UninterpretedOptionList {

-        get { return result.uninterpretedOption_; }

+        get { return PrepareBuilder().uninterpretedOption_; }

       }

       public int UninterpretedOptionCount {

         get { return result.UninterpretedOptionCount; }

@@ -5557,29 +6073,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = value;

         return this;

       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(value);

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeUninterpretedOption(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> values) {

+        PrepareBuilder();

         base.AddRange(values, result.uninterpretedOption_);

         return this;

       }

       public Builder ClearUninterpretedOption() {

+        PrepareBuilder();

         result.uninterpretedOption_.Clear();

         return this;

       }

@@ -5700,7 +6222,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(EnumOptions prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -5710,21 +6232,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new EnumOptions();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(EnumOptions cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      EnumOptions result;

+      

+      private EnumOptions PrepareBuilder() {

+        if (builderIsReadOnly) {

+          EnumOptions original = result;

+          result = new EnumOptions();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      EnumOptions result = new EnumOptions();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override EnumOptions MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new EnumOptions();

+        result = DefaultInstance ?? new EnumOptions();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -5736,13 +6285,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override EnumOptions BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.uninterpretedOption_.MakeReadOnly();

-        EnumOptions returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -5756,6 +6304,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(EnumOptions other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.EnumOptions.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.uninterpretedOption_.Count != 0) {

           base.AddRange(other.uninterpretedOption_, result.uninterpretedOption_);

         }

@@ -5769,6 +6318,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -5817,7 +6367,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> UninterpretedOptionList {

-        get { return result.uninterpretedOption_; }

+        get { return PrepareBuilder().uninterpretedOption_; }

       }

       public int UninterpretedOptionCount {

         get { return result.UninterpretedOptionCount; }

@@ -5827,29 +6377,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = value;

         return this;

       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(value);

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeUninterpretedOption(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> values) {

+        PrepareBuilder();

         base.AddRange(values, result.uninterpretedOption_);

         return this;

       }

       public Builder ClearUninterpretedOption() {

+        PrepareBuilder();

         result.uninterpretedOption_.Clear();

         return this;

       }

@@ -5970,7 +6526,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(EnumValueOptions prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -5980,21 +6536,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new EnumValueOptions();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(EnumValueOptions cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      EnumValueOptions result;

       

-      EnumValueOptions result = new EnumValueOptions();

+      private EnumValueOptions PrepareBuilder() {

+        if (builderIsReadOnly) {

+          EnumValueOptions original = result;

+          result = new EnumValueOptions();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override EnumValueOptions MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new EnumValueOptions();

+        result = DefaultInstance ?? new EnumValueOptions();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -6006,13 +6589,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override EnumValueOptions BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.uninterpretedOption_.MakeReadOnly();

-        EnumValueOptions returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -6026,6 +6608,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(EnumValueOptions other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.EnumValueOptions.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.uninterpretedOption_.Count != 0) {

           base.AddRange(other.uninterpretedOption_, result.uninterpretedOption_);

         }

@@ -6039,6 +6622,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -6087,7 +6671,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> UninterpretedOptionList {

-        get { return result.uninterpretedOption_; }

+        get { return PrepareBuilder().uninterpretedOption_; }

       }

       public int UninterpretedOptionCount {

         get { return result.UninterpretedOptionCount; }

@@ -6097,29 +6681,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = value;

         return this;

       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(value);

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeUninterpretedOption(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> values) {

+        PrepareBuilder();

         base.AddRange(values, result.uninterpretedOption_);

         return this;

       }

       public Builder ClearUninterpretedOption() {

+        PrepareBuilder();

         result.uninterpretedOption_.Clear();

         return this;

       }

@@ -6240,7 +6830,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(ServiceOptions prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -6250,21 +6840,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new ServiceOptions();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(ServiceOptions cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      ServiceOptions result;

+      

+      private ServiceOptions PrepareBuilder() {

+        if (builderIsReadOnly) {

+          ServiceOptions original = result;

+          result = new ServiceOptions();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      ServiceOptions result = new ServiceOptions();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override ServiceOptions MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new ServiceOptions();

+        result = DefaultInstance ?? new ServiceOptions();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -6276,13 +6893,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override ServiceOptions BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.uninterpretedOption_.MakeReadOnly();

-        ServiceOptions returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -6296,6 +6912,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(ServiceOptions other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.ServiceOptions.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.uninterpretedOption_.Count != 0) {

           base.AddRange(other.uninterpretedOption_, result.uninterpretedOption_);

         }

@@ -6309,6 +6926,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -6357,7 +6975,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> UninterpretedOptionList {

-        get { return result.uninterpretedOption_; }

+        get { return PrepareBuilder().uninterpretedOption_; }

       }

       public int UninterpretedOptionCount {

         get { return result.UninterpretedOptionCount; }

@@ -6367,29 +6985,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = value;

         return this;

       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(value);

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeUninterpretedOption(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> values) {

+        PrepareBuilder();

         base.AddRange(values, result.uninterpretedOption_);

         return this;

       }

       public Builder ClearUninterpretedOption() {

+        PrepareBuilder();

         result.uninterpretedOption_.Clear();

         return this;

       }

@@ -6510,7 +7134,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(MethodOptions prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -6520,21 +7144,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new MethodOptions();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(MethodOptions cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

       

-      MethodOptions result = new MethodOptions();

+      bool builderIsReadOnly;

+      MethodOptions result;

+      

+      private MethodOptions PrepareBuilder() {

+        if (builderIsReadOnly) {

+          MethodOptions original = result;

+          result = new MethodOptions();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

+      

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override MethodOptions MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new MethodOptions();

+        result = DefaultInstance ?? new MethodOptions();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -6546,13 +7197,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override MethodOptions BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.uninterpretedOption_.MakeReadOnly();

-        MethodOptions returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -6566,6 +7216,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(MethodOptions other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.MethodOptions.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.uninterpretedOption_.Count != 0) {

           base.AddRange(other.uninterpretedOption_, result.uninterpretedOption_);

         }

@@ -6579,6 +7230,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -6627,7 +7279,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> UninterpretedOptionList {

-        get { return result.uninterpretedOption_; }

+        get { return PrepareBuilder().uninterpretedOption_; }

       }

       public int UninterpretedOptionCount {

         get { return result.UninterpretedOptionCount; }

@@ -6637,29 +7289,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = value;

         return this;

       }

       public Builder SetUninterpretedOption(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption value) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(value);

         return this;

       }

       public Builder AddUninterpretedOption(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Builder builderForValue) {

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

+        PrepareBuilder();

         result.uninterpretedOption_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeUninterpretedOption(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption> values) {

+        PrepareBuilder();

         base.AddRange(values, result.uninterpretedOption_);

         return this;

       }

       public Builder ClearUninterpretedOption() {

+        PrepareBuilder();

         result.uninterpretedOption_.Clear();

         return this;

       }

@@ -6821,7 +7479,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         public override Builder ToBuilder() { return CreateBuilder(this); }

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

         public static Builder CreateBuilder(NamePart prototype) {

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

+          return new Builder(prototype);

         }

         

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

@@ -6831,21 +7489,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
           protected override Builder ThisBuilder {

             get { return this; }

           }

-          public Builder() {}

+          public Builder() {

+            result = DefaultInstance ?? new NamePart();

+            builderIsReadOnly = result == DefaultInstance;

+          }

+          internal Builder(NamePart cloneFrom) {

+            result = cloneFrom;

+            builderIsReadOnly = true;

+          }

+          

+          bool builderIsReadOnly;

+          NamePart result;

+          

+          private NamePart PrepareBuilder() {

+            if (builderIsReadOnly) {

+              NamePart original = result;

+              result = new NamePart();

+              builderIsReadOnly = false;

+              MergeFrom(original);

+            }

+            return result;

+          }

           

-          NamePart result = new NamePart();

+          public override bool IsInitialized {

+            get { return result.IsInitialized; }

+          }

           

           protected override NamePart MessageBeingBuilt {

-            get { return result; }

+            get { return PrepareBuilder(); }

           }

           

           public override Builder Clear() {

-            result = new NamePart();

+            result = DefaultInstance ?? new NamePart();

+            builderIsReadOnly = true;

             return this;

           }

           

           public override Builder Clone() {

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

+            if (builderIsReadOnly) {

+              return new Builder(result);

+            } else {

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

+            }

           }

           

           public override pbd::MessageDescriptor DescriptorForType {

@@ -6857,12 +7542,11 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
           }

           

           public override NamePart BuildPartial() {

-            if (result == null) {

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

+            if (builderIsReadOnly) {

+              return result;

             }

-            NamePart returnMe = result;

-            result = null;

-            return returnMe;

+            builderIsReadOnly = true;

+            return result;

           }

           

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

@@ -6876,6 +7560,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
           

           public override Builder MergeFrom(NamePart other) {

             if (other == global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Types.NamePart.DefaultInstance) return this;

+            PrepareBuilder();

             if (other.HasNamePart_) {

               NamePart_ = other.NamePart_;

             }

@@ -6891,6 +7576,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
           }

           

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

+            PrepareBuilder();

             pb::UnknownFieldSet.Builder unknownFields = null;

             uint tag;

             string field_name;

@@ -6951,11 +7637,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
           }

           public Builder SetNamePart_(string value) {

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

+            PrepareBuilder();

             result.hasNamePart_ = true;

             result.namePart_ = value;

             return this;

           }

           public Builder ClearNamePart_() {

+            PrepareBuilder();

             result.hasNamePart_ = false;

             result.namePart_ = "";

             return this;

@@ -6969,11 +7657,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
             set { SetIsExtension(value); }

           }

           public Builder SetIsExtension(bool value) {

+            PrepareBuilder();

             result.hasIsExtension = true;

             result.isExtension_ = value;

             return this;

           }

           public Builder ClearIsExtension() {

+            PrepareBuilder();

             result.hasIsExtension = false;

             result.isExtension_ = false;

             return this;

@@ -7148,7 +7838,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
     public override Builder ToBuilder() { return CreateBuilder(this); }

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

     public static Builder CreateBuilder(UninterpretedOption prototype) {

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

+      return new Builder(prototype);

     }

     

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

@@ -7158,21 +7848,48 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       protected override Builder ThisBuilder {

         get { return this; }

       }

-      public Builder() {}

+      public Builder() {

+        result = DefaultInstance ?? new UninterpretedOption();

+        builderIsReadOnly = result == DefaultInstance;

+      }

+      internal Builder(UninterpretedOption cloneFrom) {

+        result = cloneFrom;

+        builderIsReadOnly = true;

+      }

+      

+      bool builderIsReadOnly;

+      UninterpretedOption result;

+      

+      private UninterpretedOption PrepareBuilder() {

+        if (builderIsReadOnly) {

+          UninterpretedOption original = result;

+          result = new UninterpretedOption();

+          builderIsReadOnly = false;

+          MergeFrom(original);

+        }

+        return result;

+      }

       

-      UninterpretedOption result = new UninterpretedOption();

+      public override bool IsInitialized {

+        get { return result.IsInitialized; }

+      }

       

       protected override UninterpretedOption MessageBeingBuilt {

-        get { return result; }

+        get { return PrepareBuilder(); }

       }

       

       public override Builder Clear() {

-        result = new UninterpretedOption();

+        result = DefaultInstance ?? new UninterpretedOption();

+        builderIsReadOnly = true;

         return this;

       }

       

       public override Builder Clone() {

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

+        if (builderIsReadOnly) {

+          return new Builder(result);

+        } else {

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

+        }

       }

       

       public override pbd::MessageDescriptor DescriptorForType {

@@ -7184,13 +7901,12 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

       public override UninterpretedOption BuildPartial() {

-        if (result == null) {

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

+        if (builderIsReadOnly) {

+          return result;

         }

         result.name_.MakeReadOnly();

-        UninterpretedOption returnMe = result;

-        result = null;

-        return returnMe;

+        builderIsReadOnly = true;

+        return result;

       }

       

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

@@ -7204,6 +7920,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       public override Builder MergeFrom(UninterpretedOption other) {

         if (other == global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.DefaultInstance) return this;

+        PrepareBuilder();

         if (other.name_.Count != 0) {

           base.AddRange(other.name_, result.name_);

         }

@@ -7231,6 +7948,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       

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

+        PrepareBuilder();

         pb::UnknownFieldSet.Builder unknownFields = null;

         uint tag;

         string field_name;

@@ -7299,7 +8017,7 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       

       

       public pbc::IPopsicleList<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Types.NamePart> NameList {

-        get { return result.name_; }

+        get { return PrepareBuilder().name_; }

       }

       public int NameCount {

         get { return result.NameCount; }

@@ -7309,29 +8027,35 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetName(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Types.NamePart value) {

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

+        PrepareBuilder();

         result.name_[index] = value;

         return this;

       }

       public Builder SetName(int index, global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Types.NamePart.Builder builderForValue) {

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

+        PrepareBuilder();

         result.name_[index] = builderForValue.Build();

         return this;

       }

       public Builder AddName(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Types.NamePart value) {

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

+        PrepareBuilder();

         result.name_.Add(value);

         return this;

       }

       public Builder AddName(global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Types.NamePart.Builder builderForValue) {

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

+        PrepareBuilder();

         result.name_.Add(builderForValue.Build());

         return this;

       }

       public Builder AddRangeName(scg::IEnumerable<global::Google.ProtocolBuffers.DescriptorProtos.UninterpretedOption.Types.NamePart> values) {

+        PrepareBuilder();

         base.AddRange(values, result.name_);

         return this;

       }

       public Builder ClearName() {

+        PrepareBuilder();

         result.name_.Clear();

         return this;

       }

@@ -7345,11 +8069,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetIdentifierValue(string value) {

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

+        PrepareBuilder();

         result.hasIdentifierValue = true;

         result.identifierValue_ = value;

         return this;

       }

       public Builder ClearIdentifierValue() {

+        PrepareBuilder();

         result.hasIdentifierValue = false;

         result.identifierValue_ = "";

         return this;

@@ -7365,11 +8091,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       [global::System.CLSCompliant(false)]

       public Builder SetPositiveIntValue(ulong value) {

+        PrepareBuilder();

         result.hasPositiveIntValue = true;

         result.positiveIntValue_ = value;

         return this;

       }

       public Builder ClearPositiveIntValue() {

+        PrepareBuilder();

         result.hasPositiveIntValue = false;

         result.positiveIntValue_ = 0UL;

         return this;

@@ -7383,11 +8111,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetNegativeIntValue(value); }

       }

       public Builder SetNegativeIntValue(long value) {

+        PrepareBuilder();

         result.hasNegativeIntValue = true;

         result.negativeIntValue_ = value;

         return this;

       }

       public Builder ClearNegativeIntValue() {

+        PrepareBuilder();

         result.hasNegativeIntValue = false;

         result.negativeIntValue_ = 0L;

         return this;

@@ -7401,11 +8131,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
         set { SetDoubleValue(value); }

       }

       public Builder SetDoubleValue(double value) {

+        PrepareBuilder();

         result.hasDoubleValue = true;

         result.doubleValue_ = value;

         return this;

       }

       public Builder ClearDoubleValue() {

+        PrepareBuilder();

         result.hasDoubleValue = false;

         result.doubleValue_ = 0D;

         return this;

@@ -7420,11 +8152,13 @@ namespace Google.ProtocolBuffers.DescriptorProtos {
       }

       public Builder SetStringValue(pb::ByteString value) {

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

+        PrepareBuilder();

         result.hasStringValue = true;

         result.stringValue_ = value;

         return this;

       }

       public Builder ClearStringValue() {

+        PrepareBuilder();

         result.hasStringValue = false;

         result.stringValue_ = pb::ByteString.Empty;

         return this;