1 files changed, 15 insertions, 3 deletions
diff --git a/src/ProtoGen/MessageFieldGenerator.cs b/src/ProtoGen/MessageFieldGenerator.cs
index b86f2c9a..25b58a60 100644
--- a/src/ProtoGen/MessageFieldGenerator.cs
+++ b/src/ProtoGen/MessageFieldGenerator.cs
@@ -48,38 +48,48 @@ namespace Google.ProtocolBuffers.ProtoGen
         public void GenerateMembers(TextGenerator writer)
         {
             writer.WriteLine("private bool has{0};", PropertyName);
-            writer.WriteLine("private {0} {1}_ = {2};", TypeName, Name, DefaultValue);
+            writer.WriteLine("private {0} {1}_;", TypeName, Name);
+            AddDeprecatedFlag(writer);
             writer.WriteLine("public bool Has{0} {{", PropertyName);
             writer.WriteLine("  get {{ return has{0}; }}", PropertyName);
             writer.WriteLine("}");
+            AddDeprecatedFlag(writer);
             writer.WriteLine("public {0} {1} {{", TypeName, PropertyName);
-            writer.WriteLine("  get {{ return {0}_; }}", Name);
+            writer.WriteLine("  get {{ return {0}_ ?? {1}; }}", Name, DefaultValue);
             writer.WriteLine("}");
         }
 
         public void GenerateBuilderMembers(TextGenerator writer)
         {
+            AddDeprecatedFlag(writer);
             writer.WriteLine("public bool Has{0} {{", PropertyName);
             writer.WriteLine(" get {{ return result.has{0}; }}", PropertyName);
             writer.WriteLine("}");
+            AddDeprecatedFlag(writer);
             writer.WriteLine("public {0} {1} {{", TypeName, PropertyName);
             writer.WriteLine("  get {{ return result.{0}; }}", PropertyName);
             writer.WriteLine("  set {{ Set{0}(value); }}", PropertyName);
             writer.WriteLine("}");
+            AddDeprecatedFlag(writer);
             writer.WriteLine("public Builder Set{0}({1} value) {{", PropertyName, TypeName);
             AddNullCheck(writer);
+            writer.WriteLine("  PrepareBuilder();");
             writer.WriteLine("  result.has{0} = true;", PropertyName);
             writer.WriteLine("  result.{0}_ = value;", Name);
             writer.WriteLine("  return this;");
             writer.WriteLine("}");
+            AddDeprecatedFlag(writer);
             writer.WriteLine("public Builder Set{0}({1}.Builder builderForValue) {{", PropertyName, TypeName);
             AddNullCheck(writer, "builderForValue");
+            writer.WriteLine("  PrepareBuilder();");
             writer.WriteLine("  result.has{0} = true;", PropertyName);
             writer.WriteLine("  result.{0}_ = builderForValue.Build();", Name);
             writer.WriteLine("  return this;");
             writer.WriteLine("}");
+            AddDeprecatedFlag(writer);
             writer.WriteLine("public Builder Merge{0}({1} value) {{", PropertyName, TypeName);
             AddNullCheck(writer);
+            writer.WriteLine("  PrepareBuilder();");
             writer.WriteLine("  if (result.has{0} &&", PropertyName);
             writer.WriteLine("      result.{0}_ != {1}) {{", Name, DefaultValue);
             writer.WriteLine("      result.{0}_ = {1}.CreateBuilder(result.{0}_).MergeFrom(value).BuildPartial();", Name,
@@ -90,9 +100,11 @@ namespace Google.ProtocolBuffers.ProtoGen
             writer.WriteLine("  result.has{0} = true;", PropertyName);
             writer.WriteLine("  return this;");
             writer.WriteLine("}");
+            AddDeprecatedFlag(writer);
             writer.WriteLine("public Builder Clear{0}() {{", PropertyName);
+            writer.WriteLine("  PrepareBuilder();");
             writer.WriteLine("  result.has{0} = false;", PropertyName);
-            writer.WriteLine("  result.{0}_ = {1};", Name, DefaultValue);
+            writer.WriteLine("  result.{0}_ = null;", Name);
             writer.WriteLine("  return this;");
             writer.WriteLine("}");
         }