diff --git a/csharp/src/Google.Protobuf.Test/JsonFormatterTest.cs b/csharp/src/Google.Protobuf.Test/JsonFormatterTest.cs
index ecd7f46b..3e7a3d2e 100644
--- a/csharp/src/Google.Protobuf.Test/JsonFormatterTest.cs
+++ b/csharp/src/Google.Protobuf.Test/JsonFormatterTest.cs
@@ -244,7 +244,6 @@ namespace Google.Protobuf
         [TestCase(null, "{ }")]
         [TestCase("x", "{ 'fooString': 'x' }")]
         [TestCase("", "{ 'fooString': '' }")]
-        [TestCase(null, "{ }")]
         public void Oneof(string fooStringValue, string expectedJson)
         {
             var message = new TestOneof();
diff --git a/csharp/src/Google.Protobuf.Test/Reflection/DescriptorsTest.cs b/csharp/src/Google.Protobuf.Test/Reflection/DescriptorsTest.cs
index 643816e6..5f3aba1a 100644
--- a/csharp/src/Google.Protobuf.Test/Reflection/DescriptorsTest.cs
+++ b/csharp/src/Google.Protobuf.Test/Reflection/DescriptorsTest.cs
@@ -251,5 +251,12 @@ namespace Google.Protobuf.Reflection
             Assert.AreEqual(new[] { 11, 1, 101, 200 }, fields.InDeclarationOrder().Select(x => x.FieldNumber));
             Assert.AreEqual(new[] { 1, 11, 101, 200 }, fields.InFieldNumberOrder().Select(x => x.FieldNumber));
         }
+
+
+        [Test]
+        public void DescriptorProtoFileDescriptor()
+        {
+            var descriptor = Google.Protobuf.Reflection.FileDescriptor.DescriptorProtoFileDescriptor;
+        }
     }
 }
diff --git a/csharp/src/Google.Protobuf/Reflection/DescriptorProtoFile.cs b/csharp/src/Google.Protobuf/Reflection/DescriptorProtoFile.cs
index 59c5e69b..39cb38f4 100644
--- a/csharp/src/Google.Protobuf/Reflection/DescriptorProtoFile.cs
+++ b/csharp/src/Google.Protobuf/Reflection/DescriptorProtoFile.cs
@@ -77,7 +77,7 @@ namespace Google.Protobuf.Reflection {
             "b3RvEgwKBG5hbWUYASABKAkSEgoKaW5wdXRfdHlwZRgCIAEoCRITCgtvdXRw", 
             "dXRfdHlwZRgDIAEoCRIvCgdvcHRpb25zGAQgASgLMh4uZ29vZ2xlLnByb3Rv", 
             "YnVmLk1ldGhvZE9wdGlvbnMSHwoQY2xpZW50X3N0cmVhbWluZxgFIAEoCDoF", 
-            "ZmFsc2USHwoQc2VydmVyX3N0cmVhbWluZxgGIAEoCDoFZmFsc2UigQUKC0Zp", 
+            "ZmFsc2USHwoQc2VydmVyX3N0cmVhbWluZxgGIAEoCDoFZmFsc2UiqgUKC0Zp", 
             "bGVPcHRpb25zEhQKDGphdmFfcGFja2FnZRgBIAEoCRIcChRqYXZhX291dGVy", 
             "X2NsYXNzbmFtZRgIIAEoCRIiChNqYXZhX211bHRpcGxlX2ZpbGVzGAogASgI", 
             "OgVmYWxzZRIsCh1qYXZhX2dlbmVyYXRlX2VxdWFsc19hbmRfaGFzaBgUIAEo", 
@@ -89,49 +89,50 @@ namespace Google.Protobuf.Reflection {
             "aWNfc2VydmljZXMYEiABKAg6BWZhbHNlEhkKCmRlcHJlY2F0ZWQYFyABKAg6", 
             "BWZhbHNlEh8KEGNjX2VuYWJsZV9hcmVuYXMYHyABKAg6BWZhbHNlEhkKEW9i", 
             "amNfY2xhc3NfcHJlZml4GCQgASgJEhgKEGNzaGFycF9uYW1lc3BhY2UYJSAB", 
-            "KAkSQwoUdW5pbnRlcnByZXRlZF9vcHRpb24Y5wcgAygLMiQuZ29vZ2xlLnBy", 
-            "b3RvYnVmLlVuaW50ZXJwcmV0ZWRPcHRpb24iOgoMT3B0aW1pemVNb2RlEgkK", 
-            "BVNQRUVEEAESDQoJQ09ERV9TSVpFEAISEAoMTElURV9SVU5USU1FEAMqCQjo", 
-            "BxCAgICAAiLmAQoOTWVzc2FnZU9wdGlvbnMSJgoXbWVzc2FnZV9zZXRfd2ly", 
-            "ZV9mb3JtYXQYASABKAg6BWZhbHNlEi4KH25vX3N0YW5kYXJkX2Rlc2NyaXB0", 
-            "b3JfYWNjZXNzb3IYAiABKAg6BWZhbHNlEhkKCmRlcHJlY2F0ZWQYAyABKAg6", 
-            "BWZhbHNlEhEKCW1hcF9lbnRyeRgHIAEoCBJDChR1bmludGVycHJldGVkX29w", 
-            "dGlvbhjnByADKAsyJC5nb29nbGUucHJvdG9idWYuVW5pbnRlcnByZXRlZE9w", 
-            "dGlvbioJCOgHEICAgIACIpgDCgxGaWVsZE9wdGlvbnMSOgoFY3R5cGUYASAB", 
-            "KA4yIy5nb29nbGUucHJvdG9idWYuRmllbGRPcHRpb25zLkNUeXBlOgZTVFJJ", 
-            "TkcSDgoGcGFja2VkGAIgASgIEj8KBmpzdHlwZRgGIAEoDjIkLmdvb2dsZS5w", 
-            "cm90b2J1Zi5GaWVsZE9wdGlvbnMuSlNUeXBlOglKU19OT1JNQUwSEwoEbGF6", 
-            "eRgFIAEoCDoFZmFsc2USGQoKZGVwcmVjYXRlZBgDIAEoCDoFZmFsc2USEwoE", 
-            "d2VhaxgKIAEoCDoFZmFsc2USQwoUdW5pbnRlcnByZXRlZF9vcHRpb24Y5wcg", 
-            "AygLMiQuZ29vZ2xlLnByb3RvYnVmLlVuaW50ZXJwcmV0ZWRPcHRpb24iLwoF", 
-            "Q1R5cGUSCgoGU1RSSU5HEAASCAoEQ09SRBABEhAKDFNUUklOR19QSUVDRRAC", 
-            "IjUKBkpTVHlwZRINCglKU19OT1JNQUwQABINCglKU19TVFJJTkcQARINCglK", 
-            "U19OVU1CRVIQAioJCOgHEICAgIACIo0BCgtFbnVtT3B0aW9ucxITCgthbGxv", 
-            "d19hbGlhcxgCIAEoCBIZCgpkZXByZWNhdGVkGAMgASgIOgVmYWxzZRJDChR1", 
-            "bmludGVycHJldGVkX29wdGlvbhjnByADKAsyJC5nb29nbGUucHJvdG9idWYu", 
-            "VW5pbnRlcnByZXRlZE9wdGlvbioJCOgHEICAgIACIn0KEEVudW1WYWx1ZU9w", 
-            "dGlvbnMSGQoKZGVwcmVjYXRlZBgBIAEoCDoFZmFsc2USQwoUdW5pbnRlcnBy", 
-            "ZXRlZF9vcHRpb24Y5wcgAygLMiQuZ29vZ2xlLnByb3RvYnVmLlVuaW50ZXJw", 
-            "cmV0ZWRPcHRpb24qCQjoBxCAgICAAiJ7Cg5TZXJ2aWNlT3B0aW9ucxIZCgpk", 
-            "ZXByZWNhdGVkGCEgASgIOgVmYWxzZRJDChR1bmludGVycHJldGVkX29wdGlv", 
-            "bhjnByADKAsyJC5nb29nbGUucHJvdG9idWYuVW5pbnRlcnByZXRlZE9wdGlv", 
-            "bioJCOgHEICAgIACInoKDU1ldGhvZE9wdGlvbnMSGQoKZGVwcmVjYXRlZBgh", 
-            "IAEoCDoFZmFsc2USQwoUdW5pbnRlcnByZXRlZF9vcHRpb24Y5wcgAygLMiQu", 
-            "Z29vZ2xlLnByb3RvYnVmLlVuaW50ZXJwcmV0ZWRPcHRpb24qCQjoBxCAgICA", 
-            "AiKeAgoTVW5pbnRlcnByZXRlZE9wdGlvbhI7CgRuYW1lGAIgAygLMi0uZ29v", 
-            "Z2xlLnByb3RvYnVmLlVuaW50ZXJwcmV0ZWRPcHRpb24uTmFtZVBhcnQSGAoQ", 
-            "aWRlbnRpZmllcl92YWx1ZRgDIAEoCRIaChJwb3NpdGl2ZV9pbnRfdmFsdWUY", 
-            "BCABKAQSGgoSbmVnYXRpdmVfaW50X3ZhbHVlGAUgASgDEhQKDGRvdWJsZV92", 
-            "YWx1ZRgGIAEoARIUCgxzdHJpbmdfdmFsdWUYByABKAwSFwoPYWdncmVnYXRl", 
-            "X3ZhbHVlGAggASgJGjMKCE5hbWVQYXJ0EhEKCW5hbWVfcGFydBgBIAIoCRIU", 
-            "Cgxpc19leHRlbnNpb24YAiACKAgi1QEKDlNvdXJjZUNvZGVJbmZvEjoKCGxv", 
-            "Y2F0aW9uGAEgAygLMiguZ29vZ2xlLnByb3RvYnVmLlNvdXJjZUNvZGVJbmZv", 
-            "LkxvY2F0aW9uGoYBCghMb2NhdGlvbhIQCgRwYXRoGAEgAygFQgIQARIQCgRz", 
-            "cGFuGAIgAygFQgIQARIYChBsZWFkaW5nX2NvbW1lbnRzGAMgASgJEhkKEXRy", 
-            "YWlsaW5nX2NvbW1lbnRzGAQgASgJEiEKGWxlYWRpbmdfZGV0YWNoZWRfY29t", 
-            "bWVudHMYBiADKAlCWAoTY29tLmdvb2dsZS5wcm90b2J1ZkIQRGVzY3JpcHRv", 
-            "clByb3Rvc0gBWgpkZXNjcmlwdG9yogIDR1BCqgIaR29vZ2xlLlByb3RvYnVm", 
-            "LlJlZmxlY3Rpb24="));
+            "KAkSJwofamF2YW5hbm9fdXNlX2RlcHJlY2F0ZWRfcGFja2FnZRgmIAEoCBJD", 
+            "ChR1bmludGVycHJldGVkX29wdGlvbhjnByADKAsyJC5nb29nbGUucHJvdG9i", 
+            "dWYuVW5pbnRlcnByZXRlZE9wdGlvbiI6CgxPcHRpbWl6ZU1vZGUSCQoFU1BF", 
+            "RUQQARINCglDT0RFX1NJWkUQAhIQCgxMSVRFX1JVTlRJTUUQAyoJCOgHEICA", 
+            "gIACIuYBCg5NZXNzYWdlT3B0aW9ucxImChdtZXNzYWdlX3NldF93aXJlX2Zv", 
+            "cm1hdBgBIAEoCDoFZmFsc2USLgofbm9fc3RhbmRhcmRfZGVzY3JpcHRvcl9h", 
+            "Y2Nlc3NvchgCIAEoCDoFZmFsc2USGQoKZGVwcmVjYXRlZBgDIAEoCDoFZmFs", 
+            "c2USEQoJbWFwX2VudHJ5GAcgASgIEkMKFHVuaW50ZXJwcmV0ZWRfb3B0aW9u", 
+            "GOcHIAMoCzIkLmdvb2dsZS5wcm90b2J1Zi5VbmludGVycHJldGVkT3B0aW9u", 
+            "KgkI6AcQgICAgAIimAMKDEZpZWxkT3B0aW9ucxI6CgVjdHlwZRgBIAEoDjIj", 
+            "Lmdvb2dsZS5wcm90b2J1Zi5GaWVsZE9wdGlvbnMuQ1R5cGU6BlNUUklORxIO", 
+            "CgZwYWNrZWQYAiABKAgSPwoGanN0eXBlGAYgASgOMiQuZ29vZ2xlLnByb3Rv", 
+            "YnVmLkZpZWxkT3B0aW9ucy5KU1R5cGU6CUpTX05PUk1BTBITCgRsYXp5GAUg", 
+            "ASgIOgVmYWxzZRIZCgpkZXByZWNhdGVkGAMgASgIOgVmYWxzZRITCgR3ZWFr", 
+            "GAogASgIOgVmYWxzZRJDChR1bmludGVycHJldGVkX29wdGlvbhjnByADKAsy", 
+            "JC5nb29nbGUucHJvdG9idWYuVW5pbnRlcnByZXRlZE9wdGlvbiIvCgVDVHlw", 
+            "ZRIKCgZTVFJJTkcQABIICgRDT1JEEAESEAoMU1RSSU5HX1BJRUNFEAIiNQoG", 
+            "SlNUeXBlEg0KCUpTX05PUk1BTBAAEg0KCUpTX1NUUklORxABEg0KCUpTX05V", 
+            "TUJFUhACKgkI6AcQgICAgAIijQEKC0VudW1PcHRpb25zEhMKC2FsbG93X2Fs", 
+            "aWFzGAIgASgIEhkKCmRlcHJlY2F0ZWQYAyABKAg6BWZhbHNlEkMKFHVuaW50", 
+            "ZXJwcmV0ZWRfb3B0aW9uGOcHIAMoCzIkLmdvb2dsZS5wcm90b2J1Zi5Vbmlu", 
+            "dGVycHJldGVkT3B0aW9uKgkI6AcQgICAgAIifQoQRW51bVZhbHVlT3B0aW9u", 
+            "cxIZCgpkZXByZWNhdGVkGAEgASgIOgVmYWxzZRJDChR1bmludGVycHJldGVk", 
+            "X29wdGlvbhjnByADKAsyJC5nb29nbGUucHJvdG9idWYuVW5pbnRlcnByZXRl", 
+            "ZE9wdGlvbioJCOgHEICAgIACInsKDlNlcnZpY2VPcHRpb25zEhkKCmRlcHJl", 
+            "Y2F0ZWQYISABKAg6BWZhbHNlEkMKFHVuaW50ZXJwcmV0ZWRfb3B0aW9uGOcH", 
+            "IAMoCzIkLmdvb2dsZS5wcm90b2J1Zi5VbmludGVycHJldGVkT3B0aW9uKgkI", 
+            "6AcQgICAgAIiegoNTWV0aG9kT3B0aW9ucxIZCgpkZXByZWNhdGVkGCEgASgI", 
+            "OgVmYWxzZRJDChR1bmludGVycHJldGVkX29wdGlvbhjnByADKAsyJC5nb29n", 
+            "bGUucHJvdG9idWYuVW5pbnRlcnByZXRlZE9wdGlvbioJCOgHEICAgIACIp4C", 
+            "ChNVbmludGVycHJldGVkT3B0aW9uEjsKBG5hbWUYAiADKAsyLS5nb29nbGUu", 
+            "cHJvdG9idWYuVW5pbnRlcnByZXRlZE9wdGlvbi5OYW1lUGFydBIYChBpZGVu", 
+            "dGlmaWVyX3ZhbHVlGAMgASgJEhoKEnBvc2l0aXZlX2ludF92YWx1ZRgEIAEo", 
+            "BBIaChJuZWdhdGl2ZV9pbnRfdmFsdWUYBSABKAMSFAoMZG91YmxlX3ZhbHVl", 
+            "GAYgASgBEhQKDHN0cmluZ192YWx1ZRgHIAEoDBIXCg9hZ2dyZWdhdGVfdmFs", 
+            "dWUYCCABKAkaMwoITmFtZVBhcnQSEQoJbmFtZV9wYXJ0GAEgAigJEhQKDGlz", 
+            "X2V4dGVuc2lvbhgCIAIoCCLVAQoOU291cmNlQ29kZUluZm8SOgoIbG9jYXRp", 
+            "b24YASADKAsyKC5nb29nbGUucHJvdG9idWYuU291cmNlQ29kZUluZm8uTG9j", 
+            "YXRpb24ahgEKCExvY2F0aW9uEhAKBHBhdGgYASADKAVCAhABEhAKBHNwYW4Y", 
+            "AiADKAVCAhABEhgKEGxlYWRpbmdfY29tbWVudHMYAyABKAkSGQoRdHJhaWxp", 
+            "bmdfY29tbWVudHMYBCABKAkSIQoZbGVhZGluZ19kZXRhY2hlZF9jb21tZW50", 
+            "cxgGIAMoCUJbChNjb20uZ29vZ2xlLnByb3RvYnVmQhBEZXNjcmlwdG9yUHJv", 
+            "dG9zSAFaCmRlc2NyaXB0b3KiAgNHUEKqAhpHb29nbGUuUHJvdG9idWYuUmVm", 
+            "bGVjdGlvbrACAQ=="));
       descriptor = pbr::FileDescriptor.InternalBuildGeneratedFileFrom(descriptorData,
           new pbr::FileDescriptor[] { },
           new pbr::GeneratedCodeInfo(null, new pbr::GeneratedCodeInfo[] {
@@ -145,7 +146,7 @@ namespace Google.Protobuf.Reflection {
             new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.EnumValueDescriptorProto), new[]{ "Name", "Number", "Options" }, null, null, null),
             new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.ServiceDescriptorProto), new[]{ "Name", "Method", "Options" }, null, null, null),
             new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.MethodDescriptorProto), new[]{ "Name", "InputType", "OutputType", "Options", "ClientStreaming", "ServerStreaming" }, null, null, null),
-            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.FileOptions), new[]{ "JavaPackage", "JavaOuterClassname", "JavaMultipleFiles", "JavaGenerateEqualsAndHash", "JavaStringCheckUtf8", "OptimizeFor", "GoPackage", "CcGenericServices", "JavaGenericServices", "PyGenericServices", "Deprecated", "CcEnableArenas", "ObjcClassPrefix", "CsharpNamespace", "UninterpretedOption" }, null, new[]{ typeof(global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode) }, null),
+            new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.FileOptions), new[]{ "JavaPackage", "JavaOuterClassname", "JavaMultipleFiles", "JavaGenerateEqualsAndHash", "JavaStringCheckUtf8", "OptimizeFor", "GoPackage", "CcGenericServices", "JavaGenericServices", "PyGenericServices", "Deprecated", "CcEnableArenas", "ObjcClassPrefix", "CsharpNamespace", "JavananoUseDeprecatedPackage", "UninterpretedOption" }, null, new[]{ typeof(global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode) }, null),
             new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.MessageOptions), new[]{ "MessageSetWireFormat", "NoStandardDescriptorAccessor", "Deprecated", "MapEntry", "UninterpretedOption" }, null, null, null),
             new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.FieldOptions), new[]{ "Ctype", "Packed", "Jstype", "Lazy", "Deprecated", "Weak", "UninterpretedOption" }, null, new[]{ typeof(global::Google.Protobuf.Reflection.FieldOptions.Types.CType), typeof(global::Google.Protobuf.Reflection.FieldOptions.Types.JSType) }, null),
             new pbr::GeneratedCodeInfo(typeof(global::Google.Protobuf.Reflection.EnumOptions), new[]{ "AllowAlias", "Deprecated", "UninterpretedOption" }, null, null, null),
@@ -191,7 +192,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.FileDescriptorProto> _repeated_file_codec
         = pb::FieldCodec.ForMessage(10, global::Google.Protobuf.Reflection.FileDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.FileDescriptorProto> file_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.FileDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.FileDescriptorProto> File {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.FileDescriptorProto> File {
       get { return file_; }
     }
 
@@ -294,7 +295,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    internal string Name {
+    public string Name {
       get { return name_; }
       set {
         name_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -303,7 +304,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int PackageFieldNumber = 2;
     private string package_ = "";
-    internal string Package {
+    public string Package {
       get { return package_; }
       set {
         package_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -314,7 +315,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<string> _repeated_dependency_codec
         = pb::FieldCodec.ForString(26);
     private readonly pbc::RepeatedField<string> dependency_ = new pbc::RepeatedField<string>();
-    internal pbc::RepeatedField<string> Dependency {
+    public pbc::RepeatedField<string> Dependency {
       get { return dependency_; }
     }
 
@@ -322,7 +323,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<int> _repeated_publicDependency_codec
         = pb::FieldCodec.ForInt32(80);
     private readonly pbc::RepeatedField<int> publicDependency_ = new pbc::RepeatedField<int>();
-    internal pbc::RepeatedField<int> PublicDependency {
+    public pbc::RepeatedField<int> PublicDependency {
       get { return publicDependency_; }
     }
 
@@ -330,7 +331,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<int> _repeated_weakDependency_codec
         = pb::FieldCodec.ForInt32(88);
     private readonly pbc::RepeatedField<int> weakDependency_ = new pbc::RepeatedField<int>();
-    internal pbc::RepeatedField<int> WeakDependency {
+    public pbc::RepeatedField<int> WeakDependency {
       get { return weakDependency_; }
     }
 
@@ -338,7 +339,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.DescriptorProto> _repeated_messageType_codec
         = pb::FieldCodec.ForMessage(34, global::Google.Protobuf.Reflection.DescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> messageType_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> MessageType {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> MessageType {
       get { return messageType_; }
     }
 
@@ -346,7 +347,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.EnumDescriptorProto> _repeated_enumType_codec
         = pb::FieldCodec.ForMessage(42, global::Google.Protobuf.Reflection.EnumDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> enumType_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> EnumType {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> EnumType {
       get { return enumType_; }
     }
 
@@ -354,7 +355,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.ServiceDescriptorProto> _repeated_service_codec
         = pb::FieldCodec.ForMessage(50, global::Google.Protobuf.Reflection.ServiceDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.ServiceDescriptorProto> service_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.ServiceDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.ServiceDescriptorProto> Service {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.ServiceDescriptorProto> Service {
       get { return service_; }
     }
 
@@ -362,13 +363,13 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.FieldDescriptorProto> _repeated_extension_codec
         = pb::FieldCodec.ForMessage(58, global::Google.Protobuf.Reflection.FieldDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> extension_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> Extension {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> Extension {
       get { return extension_; }
     }
 
     public const int OptionsFieldNumber = 8;
     private global::Google.Protobuf.Reflection.FileOptions options_;
-    internal global::Google.Protobuf.Reflection.FileOptions Options {
+    public global::Google.Protobuf.Reflection.FileOptions Options {
       get { return options_; }
       set {
         options_ = value;
@@ -377,7 +378,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int SourceCodeInfoFieldNumber = 9;
     private global::Google.Protobuf.Reflection.SourceCodeInfo sourceCodeInfo_;
-    internal global::Google.Protobuf.Reflection.SourceCodeInfo SourceCodeInfo {
+    public global::Google.Protobuf.Reflection.SourceCodeInfo SourceCodeInfo {
       get { return sourceCodeInfo_; }
       set {
         sourceCodeInfo_ = value;
@@ -386,7 +387,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int SyntaxFieldNumber = 12;
     private string syntax_ = "";
-    internal string Syntax {
+    public string Syntax {
       get { return syntax_; }
       set {
         syntax_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -638,7 +639,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    internal string Name {
+    public string Name {
       get { return name_; }
       set {
         name_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -649,7 +650,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.FieldDescriptorProto> _repeated_field_codec
         = pb::FieldCodec.ForMessage(18, global::Google.Protobuf.Reflection.FieldDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> field_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> Field {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> Field {
       get { return field_; }
     }
 
@@ -657,7 +658,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.FieldDescriptorProto> _repeated_extension_codec
         = pb::FieldCodec.ForMessage(50, global::Google.Protobuf.Reflection.FieldDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> extension_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> Extension {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.FieldDescriptorProto> Extension {
       get { return extension_; }
     }
 
@@ -665,7 +666,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.DescriptorProto> _repeated_nestedType_codec
         = pb::FieldCodec.ForMessage(26, global::Google.Protobuf.Reflection.DescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> nestedType_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> NestedType {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto> NestedType {
       get { return nestedType_; }
     }
 
@@ -673,7 +674,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.EnumDescriptorProto> _repeated_enumType_codec
         = pb::FieldCodec.ForMessage(34, global::Google.Protobuf.Reflection.EnumDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> enumType_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> EnumType {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumDescriptorProto> EnumType {
       get { return enumType_; }
     }
 
@@ -681,7 +682,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange> _repeated_extensionRange_codec
         = pb::FieldCodec.ForMessage(42, global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange> extensionRange_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange> ExtensionRange {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ExtensionRange> ExtensionRange {
       get { return extensionRange_; }
     }
 
@@ -689,13 +690,13 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.OneofDescriptorProto> _repeated_oneofDecl_codec
         = pb::FieldCodec.ForMessage(66, global::Google.Protobuf.Reflection.OneofDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.OneofDescriptorProto> oneofDecl_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.OneofDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.OneofDescriptorProto> OneofDecl {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.OneofDescriptorProto> OneofDecl {
       get { return oneofDecl_; }
     }
 
     public const int OptionsFieldNumber = 7;
     private global::Google.Protobuf.Reflection.MessageOptions options_;
-    internal global::Google.Protobuf.Reflection.MessageOptions Options {
+    public global::Google.Protobuf.Reflection.MessageOptions Options {
       get { return options_; }
       set {
         options_ = value;
@@ -706,7 +707,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange> _repeated_reservedRange_codec
         = pb::FieldCodec.ForMessage(74, global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange> reservedRange_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange> ReservedRange {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.DescriptorProto.Types.ReservedRange> ReservedRange {
       get { return reservedRange_; }
     }
 
@@ -714,7 +715,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<string> _repeated_reservedName_codec
         = pb::FieldCodec.ForString(82);
     private readonly pbc::RepeatedField<string> reservedName_ = new pbc::RepeatedField<string>();
-    internal pbc::RepeatedField<string> ReservedName {
+    public pbc::RepeatedField<string> ReservedName {
       get { return reservedName_; }
     }
 
@@ -909,7 +910,7 @@ namespace Google.Protobuf.Reflection {
 
         public const int StartFieldNumber = 1;
         private int start_;
-        internal int Start {
+        public int Start {
           get { return start_; }
           set {
             start_ = value;
@@ -918,7 +919,7 @@ namespace Google.Protobuf.Reflection {
 
         public const int EndFieldNumber = 2;
         private int end_;
-        internal int End {
+        public int End {
           get { return end_; }
           set {
             end_ = value;
@@ -1037,7 +1038,7 @@ namespace Google.Protobuf.Reflection {
 
         public const int StartFieldNumber = 1;
         private int start_;
-        internal int Start {
+        public int Start {
           get { return start_; }
           set {
             start_ = value;
@@ -1046,7 +1047,7 @@ namespace Google.Protobuf.Reflection {
 
         public const int EndFieldNumber = 2;
         private int end_;
-        internal int End {
+        public int End {
           get { return end_; }
           set {
             end_ = value;
@@ -1177,7 +1178,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    internal string Name {
+    public string Name {
       get { return name_; }
       set {
         name_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -1186,7 +1187,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NumberFieldNumber = 3;
     private int number_;
-    internal int Number {
+    public int Number {
       get { return number_; }
       set {
         number_ = value;
@@ -1195,7 +1196,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int LabelFieldNumber = 4;
     private global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Label label_ = global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Label.LABEL_OPTIONAL;
-    internal global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Label Label {
+    public global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Label Label {
       get { return label_; }
       set {
         label_ = value;
@@ -1204,7 +1205,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int TypeFieldNumber = 5;
     private global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Type type_ = global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Type.TYPE_DOUBLE;
-    internal global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Type Type {
+    public global::Google.Protobuf.Reflection.FieldDescriptorProto.Types.Type Type {
       get { return type_; }
       set {
         type_ = value;
@@ -1213,7 +1214,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int TypeNameFieldNumber = 6;
     private string typeName_ = "";
-    internal string TypeName {
+    public string TypeName {
       get { return typeName_; }
       set {
         typeName_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -1222,7 +1223,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int ExtendeeFieldNumber = 2;
     private string extendee_ = "";
-    internal string Extendee {
+    public string Extendee {
       get { return extendee_; }
       set {
         extendee_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -1231,7 +1232,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int DefaultValueFieldNumber = 7;
     private string defaultValue_ = "";
-    internal string DefaultValue {
+    public string DefaultValue {
       get { return defaultValue_; }
       set {
         defaultValue_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -1240,7 +1241,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int OneofIndexFieldNumber = 9;
     private int oneofIndex_;
-    internal int OneofIndex {
+    public int OneofIndex {
       get { return oneofIndex_; }
       set {
         oneofIndex_ = value;
@@ -1249,7 +1250,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int OptionsFieldNumber = 8;
     private global::Google.Protobuf.Reflection.FieldOptions options_;
-    internal global::Google.Protobuf.Reflection.FieldOptions Options {
+    public global::Google.Protobuf.Reflection.FieldOptions Options {
       get { return options_; }
       set {
         options_ = value;
@@ -1518,7 +1519,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    internal string Name {
+    public string Name {
       get { return name_; }
       set {
         name_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -1622,7 +1623,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    internal string Name {
+    public string Name {
       get { return name_; }
       set {
         name_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -1633,13 +1634,13 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.EnumValueDescriptorProto> _repeated_value_codec
         = pb::FieldCodec.ForMessage(18, global::Google.Protobuf.Reflection.EnumValueDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumValueDescriptorProto> value_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumValueDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumValueDescriptorProto> Value {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.EnumValueDescriptorProto> Value {
       get { return value_; }
     }
 
     public const int OptionsFieldNumber = 3;
     private global::Google.Protobuf.Reflection.EnumOptions options_;
-    internal global::Google.Protobuf.Reflection.EnumOptions Options {
+    public global::Google.Protobuf.Reflection.EnumOptions Options {
       get { return options_; }
       set {
         options_ = value;
@@ -1774,7 +1775,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    internal string Name {
+    public string Name {
       get { return name_; }
       set {
         name_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -1783,7 +1784,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NumberFieldNumber = 2;
     private int number_;
-    internal int Number {
+    public int Number {
       get { return number_; }
       set {
         number_ = value;
@@ -1792,7 +1793,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int OptionsFieldNumber = 3;
     private global::Google.Protobuf.Reflection.EnumValueOptions options_;
-    internal global::Google.Protobuf.Reflection.EnumValueOptions Options {
+    public global::Google.Protobuf.Reflection.EnumValueOptions Options {
       get { return options_; }
       set {
         options_ = value;
@@ -1934,7 +1935,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    internal string Name {
+    public string Name {
       get { return name_; }
       set {
         name_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -1945,13 +1946,13 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.MethodDescriptorProto> _repeated_method_codec
         = pb::FieldCodec.ForMessage(18, global::Google.Protobuf.Reflection.MethodDescriptorProto.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.MethodDescriptorProto> method_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.MethodDescriptorProto>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.MethodDescriptorProto> Method {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.MethodDescriptorProto> Method {
       get { return method_; }
     }
 
     public const int OptionsFieldNumber = 3;
     private global::Google.Protobuf.Reflection.ServiceOptions options_;
-    internal global::Google.Protobuf.Reflection.ServiceOptions Options {
+    public global::Google.Protobuf.Reflection.ServiceOptions Options {
       get { return options_; }
       set {
         options_ = value;
@@ -2089,7 +2090,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NameFieldNumber = 1;
     private string name_ = "";
-    internal string Name {
+    public string Name {
       get { return name_; }
       set {
         name_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -2098,7 +2099,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int InputTypeFieldNumber = 2;
     private string inputType_ = "";
-    internal string InputType {
+    public string InputType {
       get { return inputType_; }
       set {
         inputType_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -2107,7 +2108,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int OutputTypeFieldNumber = 3;
     private string outputType_ = "";
-    internal string OutputType {
+    public string OutputType {
       get { return outputType_; }
       set {
         outputType_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -2116,7 +2117,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int OptionsFieldNumber = 4;
     private global::Google.Protobuf.Reflection.MethodOptions options_;
-    internal global::Google.Protobuf.Reflection.MethodOptions Options {
+    public global::Google.Protobuf.Reflection.MethodOptions Options {
       get { return options_; }
       set {
         options_ = value;
@@ -2125,7 +2126,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int ClientStreamingFieldNumber = 5;
     private bool clientStreaming_;
-    internal bool ClientStreaming {
+    public bool ClientStreaming {
       get { return clientStreaming_; }
       set {
         clientStreaming_ = value;
@@ -2134,7 +2135,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int ServerStreamingFieldNumber = 6;
     private bool serverStreaming_;
-    internal bool ServerStreaming {
+    public bool ServerStreaming {
       get { return serverStreaming_; }
       set {
         serverStreaming_ = value;
@@ -2327,6 +2328,7 @@ namespace Google.Protobuf.Reflection {
       ccEnableArenas_ = other.ccEnableArenas_;
       objcClassPrefix_ = other.objcClassPrefix_;
       csharpNamespace_ = other.csharpNamespace_;
+      javananoUseDeprecatedPackage_ = other.javananoUseDeprecatedPackage_;
       uninterpretedOption_ = other.uninterpretedOption_.Clone();
     }
 
@@ -2336,7 +2338,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaPackageFieldNumber = 1;
     private string javaPackage_ = "";
-    internal string JavaPackage {
+    public string JavaPackage {
       get { return javaPackage_; }
       set {
         javaPackage_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -2345,7 +2347,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaOuterClassnameFieldNumber = 8;
     private string javaOuterClassname_ = "";
-    internal string JavaOuterClassname {
+    public string JavaOuterClassname {
       get { return javaOuterClassname_; }
       set {
         javaOuterClassname_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -2354,7 +2356,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaMultipleFilesFieldNumber = 10;
     private bool javaMultipleFiles_;
-    internal bool JavaMultipleFiles {
+    public bool JavaMultipleFiles {
       get { return javaMultipleFiles_; }
       set {
         javaMultipleFiles_ = value;
@@ -2363,7 +2365,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaGenerateEqualsAndHashFieldNumber = 20;
     private bool javaGenerateEqualsAndHash_;
-    internal bool JavaGenerateEqualsAndHash {
+    public bool JavaGenerateEqualsAndHash {
       get { return javaGenerateEqualsAndHash_; }
       set {
         javaGenerateEqualsAndHash_ = value;
@@ -2372,7 +2374,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaStringCheckUtf8FieldNumber = 27;
     private bool javaStringCheckUtf8_;
-    internal bool JavaStringCheckUtf8 {
+    public bool JavaStringCheckUtf8 {
       get { return javaStringCheckUtf8_; }
       set {
         javaStringCheckUtf8_ = value;
@@ -2381,7 +2383,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int OptimizeForFieldNumber = 9;
     private global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode optimizeFor_ = global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode.SPEED;
-    internal global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode OptimizeFor {
+    public global::Google.Protobuf.Reflection.FileOptions.Types.OptimizeMode OptimizeFor {
       get { return optimizeFor_; }
       set {
         optimizeFor_ = value;
@@ -2390,7 +2392,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int GoPackageFieldNumber = 11;
     private string goPackage_ = "";
-    internal string GoPackage {
+    public string GoPackage {
       get { return goPackage_; }
       set {
         goPackage_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -2399,7 +2401,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int CcGenericServicesFieldNumber = 16;
     private bool ccGenericServices_;
-    internal bool CcGenericServices {
+    public bool CcGenericServices {
       get { return ccGenericServices_; }
       set {
         ccGenericServices_ = value;
@@ -2408,7 +2410,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int JavaGenericServicesFieldNumber = 17;
     private bool javaGenericServices_;
-    internal bool JavaGenericServices {
+    public bool JavaGenericServices {
       get { return javaGenericServices_; }
       set {
         javaGenericServices_ = value;
@@ -2417,7 +2419,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int PyGenericServicesFieldNumber = 18;
     private bool pyGenericServices_;
-    internal bool PyGenericServices {
+    public bool PyGenericServices {
       get { return pyGenericServices_; }
       set {
         pyGenericServices_ = value;
@@ -2426,7 +2428,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 23;
     private bool deprecated_;
-    internal bool Deprecated {
+    public bool Deprecated {
       get { return deprecated_; }
       set {
         deprecated_ = value;
@@ -2435,7 +2437,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int CcEnableArenasFieldNumber = 31;
     private bool ccEnableArenas_;
-    internal bool CcEnableArenas {
+    public bool CcEnableArenas {
       get { return ccEnableArenas_; }
       set {
         ccEnableArenas_ = value;
@@ -2444,7 +2446,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int ObjcClassPrefixFieldNumber = 36;
     private string objcClassPrefix_ = "";
-    internal string ObjcClassPrefix {
+    public string ObjcClassPrefix {
       get { return objcClassPrefix_; }
       set {
         objcClassPrefix_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -2453,18 +2455,27 @@ namespace Google.Protobuf.Reflection {
 
     public const int CsharpNamespaceFieldNumber = 37;
     private string csharpNamespace_ = "";
-    internal string CsharpNamespace {
+    public string CsharpNamespace {
       get { return csharpNamespace_; }
       set {
         csharpNamespace_ = pb::Preconditions.CheckNotNull(value, "value");
       }
     }
 
+    public const int JavananoUseDeprecatedPackageFieldNumber = 38;
+    private bool javananoUseDeprecatedPackage_;
+    public bool JavananoUseDeprecatedPackage {
+      get { return javananoUseDeprecatedPackage_; }
+      set {
+        javananoUseDeprecatedPackage_ = value;
+      }
+    }
+
     public const int UninterpretedOptionFieldNumber = 999;
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
 
@@ -2493,6 +2504,7 @@ namespace Google.Protobuf.Reflection {
       if (CcEnableArenas != other.CcEnableArenas) return false;
       if (ObjcClassPrefix != other.ObjcClassPrefix) return false;
       if (CsharpNamespace != other.CsharpNamespace) return false;
+      if (JavananoUseDeprecatedPackage != other.JavananoUseDeprecatedPackage) return false;
       if(!uninterpretedOption_.Equals(other.uninterpretedOption_)) return false;
       return true;
     }
@@ -2513,6 +2525,7 @@ namespace Google.Protobuf.Reflection {
       if (CcEnableArenas != false) hash ^= CcEnableArenas.GetHashCode();
       if (ObjcClassPrefix.Length != 0) hash ^= ObjcClassPrefix.GetHashCode();
       if (CsharpNamespace.Length != 0) hash ^= CsharpNamespace.GetHashCode();
+      if (JavananoUseDeprecatedPackage != false) hash ^= JavananoUseDeprecatedPackage.GetHashCode();
       hash ^= uninterpretedOption_.GetHashCode();
       return hash;
     }
@@ -2578,6 +2591,10 @@ namespace Google.Protobuf.Reflection {
         output.WriteRawTag(170, 2);
         output.WriteString(CsharpNamespace);
       }
+      if (JavananoUseDeprecatedPackage != false) {
+        output.WriteRawTag(176, 2);
+        output.WriteBool(JavananoUseDeprecatedPackage);
+      }
       uninterpretedOption_.WriteTo(output, _repeated_uninterpretedOption_codec);
     }
 
@@ -2625,6 +2642,9 @@ namespace Google.Protobuf.Reflection {
       if (CsharpNamespace.Length != 0) {
         size += 2 + pb::CodedOutputStream.ComputeStringSize(CsharpNamespace);
       }
+      if (JavananoUseDeprecatedPackage != false) {
+        size += 2 + 1;
+      }
       size += uninterpretedOption_.CalculateSize(_repeated_uninterpretedOption_codec);
       return size;
     }
@@ -2675,6 +2695,9 @@ namespace Google.Protobuf.Reflection {
       if (other.CsharpNamespace.Length != 0) {
         CsharpNamespace = other.CsharpNamespace;
       }
+      if (other.JavananoUseDeprecatedPackage != false) {
+        JavananoUseDeprecatedPackage = other.JavananoUseDeprecatedPackage;
+      }
       uninterpretedOption_.Add(other.uninterpretedOption_);
     }
 
@@ -2741,6 +2764,10 @@ namespace Google.Protobuf.Reflection {
             CsharpNamespace = input.ReadString();
             break;
           }
+          case 304: {
+            JavananoUseDeprecatedPackage = input.ReadBool();
+            break;
+          }
           case 7994: {
             uninterpretedOption_.AddEntriesFrom(input, _repeated_uninterpretedOption_codec);
             break;
@@ -2796,7 +2823,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int MessageSetWireFormatFieldNumber = 1;
     private bool messageSetWireFormat_;
-    internal bool MessageSetWireFormat {
+    public bool MessageSetWireFormat {
       get { return messageSetWireFormat_; }
       set {
         messageSetWireFormat_ = value;
@@ -2805,7 +2832,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NoStandardDescriptorAccessorFieldNumber = 2;
     private bool noStandardDescriptorAccessor_;
-    internal bool NoStandardDescriptorAccessor {
+    public bool NoStandardDescriptorAccessor {
       get { return noStandardDescriptorAccessor_; }
       set {
         noStandardDescriptorAccessor_ = value;
@@ -2814,7 +2841,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 3;
     private bool deprecated_;
-    internal bool Deprecated {
+    public bool Deprecated {
       get { return deprecated_; }
       set {
         deprecated_ = value;
@@ -2823,7 +2850,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int MapEntryFieldNumber = 7;
     private bool mapEntry_;
-    internal bool MapEntry {
+    public bool MapEntry {
       get { return mapEntry_; }
       set {
         mapEntry_ = value;
@@ -2834,7 +2861,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
 
@@ -2996,7 +3023,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int CtypeFieldNumber = 1;
     private global::Google.Protobuf.Reflection.FieldOptions.Types.CType ctype_ = global::Google.Protobuf.Reflection.FieldOptions.Types.CType.STRING;
-    internal global::Google.Protobuf.Reflection.FieldOptions.Types.CType Ctype {
+    public global::Google.Protobuf.Reflection.FieldOptions.Types.CType Ctype {
       get { return ctype_; }
       set {
         ctype_ = value;
@@ -3005,7 +3032,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int PackedFieldNumber = 2;
     private bool packed_;
-    internal bool Packed {
+    public bool Packed {
       get { return packed_; }
       set {
         packed_ = value;
@@ -3014,7 +3041,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int JstypeFieldNumber = 6;
     private global::Google.Protobuf.Reflection.FieldOptions.Types.JSType jstype_ = global::Google.Protobuf.Reflection.FieldOptions.Types.JSType.JS_NORMAL;
-    internal global::Google.Protobuf.Reflection.FieldOptions.Types.JSType Jstype {
+    public global::Google.Protobuf.Reflection.FieldOptions.Types.JSType Jstype {
       get { return jstype_; }
       set {
         jstype_ = value;
@@ -3023,7 +3050,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int LazyFieldNumber = 5;
     private bool lazy_;
-    internal bool Lazy {
+    public bool Lazy {
       get { return lazy_; }
       set {
         lazy_ = value;
@@ -3032,7 +3059,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 3;
     private bool deprecated_;
-    internal bool Deprecated {
+    public bool Deprecated {
       get { return deprecated_; }
       set {
         deprecated_ = value;
@@ -3041,7 +3068,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int WeakFieldNumber = 10;
     private bool weak_;
-    internal bool Weak {
+    public bool Weak {
       get { return weak_; }
       set {
         weak_ = value;
@@ -3052,7 +3079,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
 
@@ -3260,7 +3287,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int AllowAliasFieldNumber = 2;
     private bool allowAlias_;
-    internal bool AllowAlias {
+    public bool AllowAlias {
       get { return allowAlias_; }
       set {
         allowAlias_ = value;
@@ -3269,7 +3296,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 3;
     private bool deprecated_;
-    internal bool Deprecated {
+    public bool Deprecated {
       get { return deprecated_; }
       set {
         deprecated_ = value;
@@ -3280,7 +3307,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
 
@@ -3405,7 +3432,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 1;
     private bool deprecated_;
-    internal bool Deprecated {
+    public bool Deprecated {
       get { return deprecated_; }
       set {
         deprecated_ = value;
@@ -3416,7 +3443,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
 
@@ -3525,7 +3552,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 33;
     private bool deprecated_;
-    internal bool Deprecated {
+    public bool Deprecated {
       get { return deprecated_; }
       set {
         deprecated_ = value;
@@ -3536,7 +3563,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
 
@@ -3645,7 +3672,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int DeprecatedFieldNumber = 33;
     private bool deprecated_;
-    internal bool Deprecated {
+    public bool Deprecated {
       get { return deprecated_; }
       set {
         deprecated_ = value;
@@ -3656,7 +3683,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption> _repeated_uninterpretedOption_codec
         = pb::FieldCodec.ForMessage(7994, global::Google.Protobuf.Reflection.UninterpretedOption.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> uninterpretedOption_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption> UninterpretedOption {
       get { return uninterpretedOption_; }
     }
 
@@ -3772,13 +3799,13 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart> _repeated_name_codec
         = pb::FieldCodec.ForMessage(18, global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart> name_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart> Name {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.UninterpretedOption.Types.NamePart> Name {
       get { return name_; }
     }
 
     public const int IdentifierValueFieldNumber = 3;
     private string identifierValue_ = "";
-    internal string IdentifierValue {
+    public string IdentifierValue {
       get { return identifierValue_; }
       set {
         identifierValue_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -3787,7 +3814,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int PositiveIntValueFieldNumber = 4;
     private ulong positiveIntValue_;
-    internal ulong PositiveIntValue {
+    public ulong PositiveIntValue {
       get { return positiveIntValue_; }
       set {
         positiveIntValue_ = value;
@@ -3796,7 +3823,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int NegativeIntValueFieldNumber = 5;
     private long negativeIntValue_;
-    internal long NegativeIntValue {
+    public long NegativeIntValue {
       get { return negativeIntValue_; }
       set {
         negativeIntValue_ = value;
@@ -3805,7 +3832,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int DoubleValueFieldNumber = 6;
     private double doubleValue_;
-    internal double DoubleValue {
+    public double DoubleValue {
       get { return doubleValue_; }
       set {
         doubleValue_ = value;
@@ -3814,7 +3841,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int StringValueFieldNumber = 7;
     private pb::ByteString stringValue_ = pb::ByteString.Empty;
-    internal pb::ByteString StringValue {
+    public pb::ByteString StringValue {
       get { return stringValue_; }
       set {
         stringValue_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -3823,7 +3850,7 @@ namespace Google.Protobuf.Reflection {
 
     public const int AggregateValueFieldNumber = 8;
     private string aggregateValue_ = "";
-    internal string AggregateValue {
+    public string AggregateValue {
       get { return aggregateValue_; }
       set {
         aggregateValue_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -4016,7 +4043,7 @@ namespace Google.Protobuf.Reflection {
 
         public const int NamePart_FieldNumber = 1;
         private string namePart_ = "";
-        internal string NamePart_ {
+        public string NamePart_ {
           get { return namePart_; }
           set {
             namePart_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -4025,7 +4052,7 @@ namespace Google.Protobuf.Reflection {
 
         public const int IsExtensionFieldNumber = 2;
         private bool isExtension_;
-        internal bool IsExtension {
+        public bool IsExtension {
           get { return isExtension_; }
           set {
             isExtension_ = value;
@@ -4150,7 +4177,7 @@ namespace Google.Protobuf.Reflection {
     private static readonly pb::FieldCodec<global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location> _repeated_location_codec
         = pb::FieldCodec.ForMessage(10, global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location.Parser);
     private readonly pbc::RepeatedField<global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location> location_ = new pbc::RepeatedField<global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location>();
-    internal pbc::RepeatedField<global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location> Location {
+    public pbc::RepeatedField<global::Google.Protobuf.Reflection.SourceCodeInfo.Types.Location> Location {
       get { return location_; }
     }
 
@@ -4249,7 +4276,7 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::FieldCodec<int> _repeated_path_codec
             = pb::FieldCodec.ForInt32(10);
         private readonly pbc::RepeatedField<int> path_ = new pbc::RepeatedField<int>();
-        internal pbc::RepeatedField<int> Path {
+        public pbc::RepeatedField<int> Path {
           get { return path_; }
         }
 
@@ -4257,13 +4284,13 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::FieldCodec<int> _repeated_span_codec
             = pb::FieldCodec.ForInt32(18);
         private readonly pbc::RepeatedField<int> span_ = new pbc::RepeatedField<int>();
-        internal pbc::RepeatedField<int> Span {
+        public pbc::RepeatedField<int> Span {
           get { return span_; }
         }
 
         public const int LeadingCommentsFieldNumber = 3;
         private string leadingComments_ = "";
-        internal string LeadingComments {
+        public string LeadingComments {
           get { return leadingComments_; }
           set {
             leadingComments_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -4272,7 +4299,7 @@ namespace Google.Protobuf.Reflection {
 
         public const int TrailingCommentsFieldNumber = 4;
         private string trailingComments_ = "";
-        internal string TrailingComments {
+        public string TrailingComments {
           get { return trailingComments_; }
           set {
             trailingComments_ = pb::Preconditions.CheckNotNull(value, "value");
@@ -4283,7 +4310,7 @@ namespace Google.Protobuf.Reflection {
         private static readonly pb::FieldCodec<string> _repeated_leadingDetachedComments_codec
             = pb::FieldCodec.ForString(50);
         private readonly pbc::RepeatedField<string> leadingDetachedComments_ = new pbc::RepeatedField<string>();
-        internal pbc::RepeatedField<string> LeadingDetachedComments {
+        public pbc::RepeatedField<string> LeadingDetachedComments {
           get { return leadingDetachedComments_; }
         }
 
diff --git a/objectivec/generate_descriptors_proto.sh b/objectivec/generate_descriptors_proto.sh
index b3ecf398..84ba0738 100755
--- a/objectivec/generate_descriptors_proto.sh
+++ b/objectivec/generate_descriptors_proto.sh
@@ -11,7 +11,6 @@ set -eu
 
 readonly ScriptDir=$(dirname "$(echo $0 | sed -e "s,^\([^/]\),$(pwd)/\1,")")
 readonly ProtoRootDir="${ScriptDir}/.."
-readonly ProtoC="${ProtoRootDir}/src/protoc"
 
 pushd "${ProtoRootDir}" > /dev/null
 
@@ -35,7 +34,7 @@ fi
 cd src
 make $@ protoc
 
-declare -a RUNTIME_PROTO_FILES=(\
+declare -a RUNTIME_PROTO_FILES=( \
   google/protobuf/any.proto \
   google/protobuf/api.proto \
   google/protobuf/descriptor.proto \
@@ -49,5 +48,3 @@ declare -a RUNTIME_PROTO_FILES=(\
   google/protobuf/wrappers.proto)
 
 ./protoc --objc_out="${ProtoRootDir}/objectivec" ${RUNTIME_PROTO_FILES[@]}
-
-popd > /dev/null
diff --git a/src/google/protobuf/compiler/csharp/csharp_field_base.cc b/src/google/protobuf/compiler/csharp/csharp_field_base.cc
index cd29bcf9..5df43d3f 100644
--- a/src/google/protobuf/compiler/csharp/csharp_field_base.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_field_base.cc
@@ -67,7 +67,7 @@ void FieldGeneratorBase::SetCommonFieldVariables(
     tag_bytes += ", " + SimpleItoa(tag_array[i]);
   }
 
-  (*variables)["access_level"] = class_access_level();
+  (*variables)["access_level"] = "public";
   (*variables)["tag"] = SimpleItoa(tag);
   (*variables)["tag_size"] = SimpleItoa(tag_size);
   (*variables)["tag_bytes"] = tag_bytes;
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_file.cc b/src/google/protobuf/compiler/objectivec/objectivec_file.cc
index e60ae5a6..184a84a3 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_file.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_file.cc
@@ -54,9 +54,6 @@ FileGenerator::FileGenerator(const FileDescriptor *file)
     : file_(file),
       root_class_name_(FileClassName(file)),
       is_public_dep_(false) {
-  // Validate the objc prefix.
-  ValidateObjCClassPrefix(file_);
-
   for (int i = 0; i < file_->enum_type_count(); i++) {
     EnumGenerator *generator = new EnumGenerator(file_->enum_type(i));
     enum_generators_.push_back(generator);
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_generator.cc b/src/google/protobuf/compiler/objectivec/objectivec_generator.cc
index 4449087a..375b4e0f 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_generator.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_generator.cc
@@ -57,8 +57,13 @@ bool ObjectiveCGenerator::Generate(const FileDescriptor* file,
     return false;
   }
 
-  FileGenerator file_generator(file);
+  // Validate the objc prefix/package pairing.
+  if (!ValidateObjCClassPrefix(file, error)) {
+    // *error will have been filled in.
+    return false;
+  }
 
+  FileGenerator file_generator(file);
   string filepath = FilePath(file);
 
   // Generate header.
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_generator.h b/src/google/protobuf/compiler/objectivec/objectivec_generator.h
index 24286ac9..09266b04 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_generator.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_generator.h
@@ -53,6 +53,7 @@ class LIBPROTOC_EXPORT ObjectiveCGenerator : public CodeGenerator {
  private:
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ObjectiveCGenerator);
 };
+
 }  // namespace objectivec
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc b/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc
index 45d122d1..b724d35c 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc
@@ -28,10 +28,18 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+#ifdef _MSC_VER
+#include <io.h>
+#else
+#include <unistd.h>
+#endif
 #include <climits>
+#include <errno.h>
+#include <fcntl.h>
 #include <fstream>
 #include <iostream>
 #include <sstream>
+#include <stdlib.h>
 #include <vector>
 
 #include <google/protobuf/stubs/hash.h>
@@ -39,6 +47,7 @@
 #include <google/protobuf/io/coded_stream.h>
 #include <google/protobuf/io/zero_copy_stream_impl.h>
 #include <google/protobuf/descriptor.pb.h>
+#include <google/protobuf/stubs/common.h>
 #include <google/protobuf/stubs/strutil.h>
 
 // NOTE: src/google/protobuf/compiler/plugin.cc makes use of cerr for some
@@ -51,45 +60,6 @@ namespace objectivec {
 
 namespace {
 
-// islower()/isupper()/tolower()/toupper() change based on locale.
-//
-// src/google/protobuf/stubs/strutil.h:150 has the same pattern. For the
-// Objective C plugin, test failures were seen on TravisCI because isupper('A')
-// was coming back false for some server's locale.  This approach avoids any
-// such issues.
-
-bool IsLower(const char c) {
-  return ('a' <= c && c <= 'z');
-}
-
-bool IsUpper(const char c) {
-  return ('A' <= c && c <= 'Z');
-}
-
-char ToLower(char c) {
-  if ('A' <= c && c <= 'Z') {
-    c += 'a' - 'A';
-  }
-  return c;
-}
-
-// toupper() changes based on locale.  We don't want this!
-char ToUpper(char c) {
-  if ('a' <= c && c <= 'z') {
-    c += 'A' - 'a';
-  }
-  return c;
-}
-
-string TrimString(const string& s) {
-  string::size_type start = s.find_first_not_of(" \n\r\t");
-  if (start == string::npos) {
-    return "";
-  }
-  string::size_type end = s.find_last_not_of(" \n\r\t") + 1;
-  return s.substr(start, end - start);
-}
-
 hash_set<string> MakeWordsMap(const char* const words[], size_t num_words) {
   hash_set<string> result;
   for (int i = 0; i < num_words; i++) {
@@ -115,7 +85,7 @@ string UnderscoresToCamelCase(const string& input, bool first_capitalized) {
   bool last_char_was_upper = false;
   for (int i = 0; i < input.size(); i++) {
     char c = input[i];
-    if (c >= '0' && c <= '9') {
+    if (ascii_isdigit(c)) {
       if (!last_char_was_number) {
         values.push_back(current);
         current = "";
@@ -123,7 +93,7 @@ string UnderscoresToCamelCase(const string& input, bool first_capitalized) {
       current += c;
       last_char_was_number = last_char_was_lower = last_char_was_upper = false;
       last_char_was_number = true;
-    } else if (IsLower(c)) {
+    } else if (ascii_islower(c)) {
       // lowercase letter can follow a lowercase or uppercase letter
       if (!last_char_was_lower && !last_char_was_upper) {
         values.push_back(current);
@@ -132,12 +102,12 @@ string UnderscoresToCamelCase(const string& input, bool first_capitalized) {
       current += c;  // already lower
       last_char_was_number = last_char_was_lower = last_char_was_upper = false;
       last_char_was_lower = true;
-    } else if (IsUpper(c)) {
+    } else if (ascii_isupper(c)) {
       if (!last_char_was_upper) {
         values.push_back(current);
         current = "";
       }
-      current += ToLower(c);
+      current += ascii_tolower(c);
       last_char_was_number = last_char_was_lower = last_char_was_upper = false;
       last_char_was_upper = true;
     } else {
@@ -151,7 +121,7 @@ string UnderscoresToCamelCase(const string& input, bool first_capitalized) {
     bool all_upper = (kUpperSegments.count(value) > 0);
     for (int j = 0; j < value.length(); j++) {
       if (j == 0 || all_upper) {
-        value[j] = ToUpper(value[j]);
+        value[j] = ascii_toupper(value[j]);
       } else {
         // Nothing, already in lower.
       }
@@ -163,7 +133,7 @@ string UnderscoresToCamelCase(const string& input, bool first_capitalized) {
     result += *i;
   }
   if ((result.length() != 0) && !first_capitalized) {
-    result[0] = ToLower(result[0]);
+    result[0] = ascii_tolower(result[0]);
   }
   return result;
 }
@@ -272,7 +242,7 @@ bool IsSpecialName(const string& name, const string* special_names,
         // If name is longer than the retained_name[i] that it matches
         // the next character must be not lower case (newton vs newTon vs
         // new_ton).
-        return !IsLower(name[length]);
+        return !ascii_islower(name[length]);
       } else {
         return true;
       }
@@ -342,30 +312,6 @@ string FileClassPrefix(const FileDescriptor* file) {
   return result;
 }
 
-void ValidateObjCClassPrefix(const FileDescriptor* file) {
-  string prefix = file->options().objc_class_prefix();
-  if (prefix.length() > 0) {
-    // NOTE: src/google/protobuf/compiler/plugin.cc makes use of cerr for some
-    // error cases, so it seems to be ok to use as a back door for errors.
-    if (!IsUpper(prefix[0])) {
-      cerr << endl
-           << "protoc:0: warning: Invalid 'option objc_class_prefix = \""
-           << prefix << "\";' in '" << file->name() << "';"
-           << " it should start with a capital letter."
-           << endl;
-      cerr.flush();
-    }
-    if (prefix.length() < 3) {
-      cerr << endl
-           << "protoc:0: warning: Invalid 'option objc_class_prefix = \""
-           << prefix << "\";' in '" << file->name() << "';"
-           << " Apple recommends they should be at least 3 characters long."
-           << endl;
-      cerr.flush();
-    }
-  }
-}
-
 string FileClassName(const FileDescriptor* file) {
   string name = FileClassPrefix(file);
   name += UnderscoresToCamelCase(StripProto(BaseFileName(file)), true);
@@ -453,10 +399,10 @@ string UnCamelCaseEnumShortName(const string& name) {
   string result;
   for (int i = 0; i < name.size(); i++) {
     char c = name[i];
-    if (i > 0 && c >= 'A' && c <= 'Z') {
+    if (i > 0 && ascii_isupper(c)) {
       result += '_';
     }
-    result += ToUpper(c);
+    result += ascii_toupper(c);
   }
   return result;
 }
@@ -487,7 +433,7 @@ string FieldNameCapitalized(const FieldDescriptor* field) {
   // name.
   string result = FieldName(field);
   if (result.length() > 0) {
-    result[0] = ToUpper(result[0]);
+    result[0] = ascii_toupper(result[0]);
   }
   return result;
 }
@@ -511,7 +457,7 @@ string OneofNameCapitalized(const OneofDescriptor* descriptor) {
   // Use the common handling and then up-case the first letter.
   string result = OneofName(descriptor);
   if (result.length() > 0) {
-    result[0] = ToUpper(result[0]);
+    result[0] = ascii_toupper(result[0]);
   }
   return result;
 }
@@ -526,8 +472,8 @@ string UnCamelCaseFieldName(const string& name, const FieldDescriptor* field) {
   }
   if (field->type() == FieldDescriptor::TYPE_GROUP) {
     if (worker.length() > 0) {
-      if (worker[0] >= 'a' && worker[0] <= 'z') {
-        worker[0] = ToUpper(worker[0]);
+      if (ascii_islower(worker[0])) {
+        worker[0] = ascii_toupper(worker[0]);
       }
     }
     return worker;
@@ -535,11 +481,11 @@ string UnCamelCaseFieldName(const string& name, const FieldDescriptor* field) {
     string result;
     for (int i = 0; i < worker.size(); i++) {
       char c = worker[i];
-      if (c >= 'A' && c <= 'Z') {
+      if (ascii_isupper(c)) {
         if (i > 0) {
           result += '_';
         }
-        result += ToLower(c);
+        result += ascii_tolower(c);
       } else {
         result += c;
       }
@@ -831,6 +777,252 @@ string BuildCommentsString(const SourceLocation& location) {
   return final_comments;
 }
 
+namespace {
+
+// Internal helper class that parses the expected package to prefix mappings
+// file.
+class Parser {
+ public:
+  Parser(map<string, string>* inout_package_to_prefix_map)
+      : prefix_map_(inout_package_to_prefix_map), line_(0) {}
+
+  // Parses a check of input, returning success/failure.
+  bool ParseChunk(StringPiece chunk);
+
+  // Should be called to finish parsing (after all input has been provided via
+  // ParseChunk()).  Returns success/failure.
+  bool Finish();
+
+  int last_line() const { return line_; }
+  string error_str() const { return error_str_; }
+
+ private:
+  bool ParseLoop();
+
+  map<string, string>* prefix_map_;
+  int line_;
+  string error_str_;
+  StringPiece p_;
+  string leftover_;
+};
+
+bool Parser::ParseChunk(StringPiece chunk) {
+  if (!leftover_.empty()) {
+    chunk.AppendToString(&leftover_);
+    p_ = StringPiece(leftover_);
+  } else {
+    p_ = chunk;
+  }
+  bool result = ParseLoop();
+  if (p_.empty()) {
+    leftover_.clear();
+  } else {
+    leftover_ = p_.ToString();
+  }
+  return result;
+}
+
+bool Parser::Finish() {
+  if (leftover_.empty()) {
+    return true;
+  }
+  // Force a newline onto the end to finish parsing.
+  p_ = StringPiece(leftover_ + "\n");
+  if (!ParseLoop()) {
+    return false;
+  }
+  return p_.empty();  // Everything used?
+}
+
+static bool ascii_isnewline(char c) { return c == '\n' || c == '\r'; }
+
+bool ReadLine(StringPiece* input, StringPiece* line) {
+  for (int len = 0; len < input->size(); ++len) {
+    if (ascii_isnewline((*input)[len])) {
+      *line = StringPiece(input->data(), len);
+      ++len;  // advance over the newline
+      *input = StringPiece(input->data() + len, input->size() - len);
+      return true;
+    }
+  }
+  return false;  // Ran out of input with no newline.
+}
+
+void TrimWhitespace(StringPiece* input) {
+  while (!input->empty() && ascii_isspace(*input->data())) {
+    input->remove_prefix(1);
+  }
+  while (!input->empty() && ascii_isspace((*input)[input->length() - 1])) {
+    input->remove_suffix(1);
+  }
+}
+
+void RemoveComment(StringPiece* input) {
+  int offset = input->find('#');
+  if (offset != StringPiece::npos) {
+    input->remove_suffix(input->length() - offset);
+  }
+}
+
+bool Parser::ParseLoop() {
+  StringPiece line;
+  while (ReadLine(&p_, &line)) {
+    ++line_;
+    RemoveComment(&line);
+    TrimWhitespace(&line);
+    if (line.size() == 0) {
+      continue;  // Blank line.
+    }
+    int offset = line.find('=');
+    if (offset == StringPiece::npos) {
+      error_str_ =
+          string("Line without equal sign: '") + line.ToString() + "'.";
+      return false;
+    }
+    StringPiece package(line, 0, offset);
+    StringPiece prefix(line, offset + 1, line.length() - offset - 1);
+    TrimWhitespace(&package);
+    TrimWhitespace(&prefix);
+    // Don't really worry about error checking the the package/prefix for
+    // being valid.  Assume the file is validated when it is created/edited.
+    (*prefix_map_)[package.ToString()] = prefix.ToString();
+  }
+  return true;
+}
+
+bool LoadExpectedPackagePrefixes(map<string, string>* prefix_map,
+                                 string* out_expect_file_path,
+                                 string* out_error) {
+  const char* file_path = getenv("GPB_OBJC_EXPECTED_PACKAGE_PREFIXES");
+  if (file_path == NULL) {
+    return true;
+  }
+
+  int fd;
+  do {
+    fd = open(file_path, O_RDONLY);
+  } while (fd < 0 && errno == EINTR);
+  if (fd < 0) {
+    *out_error =
+        string(file_path) + ":0:0: error: Unable to open." + strerror(errno);
+    return false;
+  }
+  io::FileInputStream file_stream(fd);
+  file_stream.SetCloseOnDelete(true);
+  *out_expect_file_path = file_path;
+
+  Parser parser(prefix_map);
+  const void* buf;
+  int buf_len;
+  while (file_stream.Next(&buf, &buf_len)) {
+    if (buf_len == 0) {
+      continue;
+    }
+
+    if (!parser.ParseChunk(StringPiece(static_cast<const char*>(buf), buf_len))) {
+      *out_error = string(file_path) + ":" + SimpleItoa(parser.last_line()) +
+                   ":0: error: " + parser.error_str();
+      return false;
+    }
+  }
+  return parser.Finish();
+}
+
+}  // namespace
+
+bool ValidateObjCClassPrefix(const FileDescriptor* file, string* out_error) {
+  const string prefix = file->options().objc_class_prefix();
+  const string package = file->package();
+
+  // NOTE: src/google/protobuf/compiler/plugin.cc makes use of cerr for some
+  // error cases, so it seems to be ok to use as a back door for warnings.
+
+  // First Check: Warning - if there is a prefix, ensure it is is a reasonable
+  // value according to Apple's rules.
+  if (prefix.length()) {
+    if (!ascii_isupper(prefix[0])) {
+      cerr << endl
+           << "protoc:0: warning: Invalid 'option objc_class_prefix = \""
+           << prefix << "\";' in '" << file->name() << "';"
+           << " it should start with a capital letter." << endl;
+      cerr.flush();
+    }
+    if (prefix.length() < 3) {
+      cerr << endl
+           << "protoc:0: warning: Invalid 'option objc_class_prefix = \""
+           << prefix << "\";' in '" << file->name() << "';"
+           << " Apple recommends they should be at least 3 characters long."
+           << endl;
+      cerr.flush();
+    }
+  }
+
+  // Load any expected package prefixes to validate against those.
+  map<string, string> expected_package_prefixes;
+  string expect_file_path;
+  if (!LoadExpectedPackagePrefixes(&expected_package_prefixes,
+                                   &expect_file_path, out_error)) {
+    return false;
+  }
+
+  // If there are no expected prefixes, out of here.
+  if (expected_package_prefixes.size() == 0) {
+    return true;
+  }
+
+  // Second Check: Error - See if there was an expected prefix for the package
+  // and report if it doesn't match.
+  map<string, string>::iterator package_match =
+      expected_package_prefixes.find(package);
+  if (package_match != expected_package_prefixes.end()) {
+    // There was an entry, and...
+    if (package_match->second == prefix) {
+      // ...it matches.  All good, out of here!
+      return true;
+    } else {
+      // ...it didn't match!
+      *out_error = "protoc:0: error: Expected 'option objc_class_prefix = \"" +
+                   package_match->second + "\";' in '" + file->name() + "'";
+      if (prefix.length()) {
+        *out_error += "; but found '" + prefix + "' instead";
+      }
+      *out_error += ".";
+      return false;
+    }
+  }
+
+  // Third Check: Error - If there was a prefix make sure it wasn't expected
+  // for a different package instead (overlap is allowed, but it has to be
+  // listed as an expected overlap).
+  if (prefix.length()) {
+    for (map<string, string>::iterator i = expected_package_prefixes.begin();
+         i != expected_package_prefixes.end(); ++i) {
+      if (i->second == prefix) {
+        *out_error =
+            "protoc:0: error: Found 'option objc_class_prefix = \"" + prefix +
+            "\";' in '" + file->name() +
+            "'; that prefix is already used for 'package " + i->first +
+            ";'. It can only be reused by listing it in the expected file (" +
+            expect_file_path + ").";
+        return false;  // Only report first usage of the prefix.
+      }
+    }
+  }
+
+  // Fourth Check: Warning - If there was a prefix, and it wasn't expected,
+  // issue a warning suggesting it gets added to the file.
+  if (prefix.length()) {
+    cerr << endl
+         << "protoc:0: warning: Found 'option objc_class_prefix = \"" << prefix
+         << "\";' in '" << file->name() << "';"
+         << " should you add it to the expected prefixes file ("
+         << expect_file_path << ")?" << endl;
+    cerr.flush();
+  }
+
+  return true;
+}
+
 void TextFormatDecodeData::AddString(int32 key,
                                      const string& input_for_decode,
                                      const string& desired_output) {
@@ -898,7 +1090,7 @@ class DecodeDataBuilder {
 
   void AddChar(const char desired) {
     ++segment_len_;
-    is_all_upper_ &= IsUpper(desired);
+    is_all_upper_ &= ascii_isupper(desired);
   }
 
   void Push() {
@@ -913,9 +1105,9 @@ class DecodeDataBuilder {
   bool AddFirst(const char desired, const char input) {
     if (desired == input) {
       op_ = kOpAsIs;
-    } else if (desired == ToUpper(input)) {
+    } else if (desired == ascii_toupper(input)) {
       op_ = kOpFirstUpper;
-    } else if (desired == ToLower(input)) {
+    } else if (desired == ascii_tolower(input)) {
       op_ = kOpFirstLower;
     } else {
       // Can't be transformed to match.
@@ -953,7 +1145,7 @@ bool DecodeDataBuilder::AddCharacter(const char desired, const char input) {
   if (desired == input) {
     // If we aren't transforming it, or we're upper casing it and it is
     // supposed to be uppercase; just add it to the segment.
-    if ((op_ != kOpAllUpper) || IsUpper(desired)) {
+    if ((op_ != kOpAllUpper) || ascii_isupper(desired)) {
       AddChar(desired);
       return true;
     }
@@ -965,7 +1157,7 @@ bool DecodeDataBuilder::AddCharacter(const char desired, const char input) {
 
   // If we need to uppercase, and everything so far has been uppercase,
   // promote op to AllUpper.
-  if ((desired == ToUpper(input)) && is_all_upper_) {
+  if ((desired == ascii_toupper(input)) && is_all_upper_) {
     op_ = kOpAllUpper;
     AddChar(desired);
     return true;
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_helpers.h b/src/google/protobuf/compiler/objectivec/objectivec_helpers.h
index 10d51a34..072a2e57 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_helpers.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_helpers.h
@@ -62,9 +62,6 @@ string FileName(const FileDescriptor* file);
 // declared in the proto package.
 string FilePath(const FileDescriptor* file);
 
-// Checks the prefix for a given file and outputs any warnings/errors needed.
-void ValidateObjCClassPrefix(const FileDescriptor* file);
-
 // Gets the name of the root class we'll generate in the file.  This class
 // is not meant for external consumption, but instead contains helpers that
 // the rest of the the classes need
@@ -145,6 +142,11 @@ string BuildFlagsString(const vector<string>& strings);
 
 string BuildCommentsString(const SourceLocation& location);
 
+// Checks the prefix for a given file and outputs any warnings needed, if
+// there are flat out errors, then out_error is filled in and the result is
+// false.
+bool ValidateObjCClassPrefix(const FileDescriptor* file, string *out_error);
+
 // Generate decode data needed for ObjC's GPBDecodeTextFormatName() to transform
 // the input into the the expected output.
 class LIBPROTOC_EXPORT TextFormatDecodeData {