Merge branch 'master' of github.com:google/protobuf

20 files changed, 485 insertions, 319 deletions

diff --git a/src/google/protobuf/compiler/objectivec/objectivec_enum.cc b/src/google/protobuf/compiler/objectivec/objectivec_enum.cc
index d6f01c60..3f81dcb8 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_enum.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_enum.cc
@@ -80,10 +80,12 @@ void EnumGenerator::GenerateHeader(io::Printer* printer) {
   if (HasPreservingUnknownEnumSemantics(descriptor_->file())) {
     // Include the unknown value.
     printer->Print(
+      "/// Value used if any message's field encounters a value that is not defined\n"
+      "/// by this enum. The message will also have C functions to get/set the rawValue\n"
+      "/// of the field.\n"
       "$name$_GPBUnrecognizedEnumeratorValue = kGPBUnrecognizedEnumeratorValue,\n",
       "name", name_);
   }
-
   for (int i = 0; i < all_values_.size(); i++) {
     SourceLocation location;
     if (all_values_[i]->GetSourceLocation(&location)) {
@@ -107,6 +109,8 @@ void EnumGenerator::GenerateHeader(io::Printer* printer) {
       "\n"
       "GPBEnumDescriptor *$name$_EnumDescriptor(void);\n"
       "\n"
+      "/// Checks to see if the given value is defined by the enum or was not known at\n"
+      "/// the time this source was generated.\n"
       "BOOL $name$_IsValidValue(int32_t value);\n"
       "\n",
       "name", name_);
@@ -118,16 +122,6 @@ void EnumGenerator::GenerateSource(io::Printer* printer) {
       "\n",
       "name", name_);
 
-  printer->Print(
-      "GPBEnumDescriptor *$name$_EnumDescriptor(void) {\n"
-      "  static GPBEnumDescriptor *descriptor = NULL;\n"
-      "  if (!descriptor) {\n"
-      "    static GPBMessageEnumValueDescription values[] = {\n",
-      "name", name_);
-  printer->Indent();
-  printer->Indent();
-  printer->Indent();
-
   // Note: For the TextFormat decode info, we can't use the enum value as
   // the key because protocol buffer enums have 'allow_alias', which lets
   // a value be used more than once. Instead, the index into the list of
@@ -135,41 +129,66 @@ void EnumGenerator::GenerateSource(io::Printer* printer) {
   // will be zero.
   TextFormatDecodeData text_format_decode_data;
   int enum_value_description_key = -1;
+  string text_blob;
 
   for (int i = 0; i < all_values_.size(); i++) {
     ++enum_value_description_key;
     string short_name(EnumValueShortName(all_values_[i]));
-    printer->Print("{ .name = \"$short_name$\", .number = $name$ },\n",
-                   "short_name", short_name,
-                   "name", EnumValueName(all_values_[i]));
+    text_blob += short_name + '\0';
     if (UnCamelCaseEnumShortName(short_name) != all_values_[i]->name()) {
       text_format_decode_data.AddString(enum_value_description_key, short_name,
                                         all_values_[i]->name());
     }
   }
-  printer->Outdent();
-  printer->Outdent();
-  printer->Outdent();
+
+  printer->Print(
+      "GPBEnumDescriptor *$name$_EnumDescriptor(void) {\n"
+      "  static GPBEnumDescriptor *descriptor = NULL;\n"
+      "  if (!descriptor) {\n",
+      "name", name_);
+
+  static const int kBytesPerLine = 40;  // allow for escaping
+  printer->Print(
+      "    static const char *valueNames =");
+  for (int i = 0; i < text_blob.size(); i += kBytesPerLine) {
+    printer->Print(
+        "\n        \"$data$\"",
+        "data", EscapeTrigraphs(CEscape(text_blob.substr(i, kBytesPerLine))));
+  }
+  printer->Print(
+      ";\n"
+      "    static const int32_t values[] = {\n");
+  for (int i = 0; i < all_values_.size(); i++) {
+    printer->Print("        $name$,\n",  "name", EnumValueName(all_values_[i]));
+  }
   printer->Print("    };\n");
+
   if (text_format_decode_data.num_entries() == 0) {
     printer->Print(
-        "    descriptor = [GPBEnumDescriptor allocDescriptorForName:GPBNSStringifySymbol($name$)\n"
-        "                                                   values:values\n"
-        "                                               valueCount:sizeof(values) / sizeof(GPBMessageEnumValueDescription)\n"
-        "                                             enumVerifier:$name$_IsValidValue];\n",
+        "    GPBEnumDescriptor *worker =\n"
+        "        [GPBEnumDescriptor allocDescriptorForName:GPBNSStringifySymbol($name$)\n"
+        "                                       valueNames:valueNames\n"
+        "                                           values:values\n"
+        "                                            count:(uint32_t)(sizeof(values) / sizeof(int32_t))\n"
+        "                                     enumVerifier:$name$_IsValidValue];\n",
         "name", name_);
     } else {
       printer->Print(
         "    static const char *extraTextFormatInfo = \"$extraTextFormatInfo$\";\n"
-        "    descriptor = [GPBEnumDescriptor allocDescriptorForName:GPBNSStringifySymbol($name$)\n"
-        "                                                   values:values\n"
-        "                                               valueCount:sizeof(values) / sizeof(GPBMessageEnumValueDescription)\n"
-        "                                             enumVerifier:$name$_IsValidValue\n"
-        "                                      extraTextFormatInfo:extraTextFormatInfo];\n",
+        "    GPBEnumDescriptor *worker =\n"
+        "        [GPBEnumDescriptor allocDescriptorForName:GPBNSStringifySymbol($name$)\n"
+        "                                       valueNames:valueNames\n"
+        "                                           values:values\n"
+        "                                            count:(uint32_t)(sizeof(values) / sizeof(int32_t))\n"
+        "                                     enumVerifier:$name$_IsValidValue\n"
+        "                              extraTextFormatInfo:extraTextFormatInfo];\n",
         "name", name_,
         "extraTextFormatInfo", CEscape(text_format_decode_data.Data()));
     }
     printer->Print(
+      "    if (!OSAtomicCompareAndSwapPtrBarrier(nil, worker, (void * volatile *)&descriptor)) {\n"
+      "      [worker release];\n"
+      "    }\n"
       "  }\n"
       "  return descriptor;\n"
       "}\n\n");
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_enum_field.cc b/src/google/protobuf/compiler/objectivec/objectivec_enum_field.cc
index ecc77f6b..b63bc0de 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_enum_field.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_enum_field.cc
@@ -59,6 +59,9 @@ void SetEnumVariables(const FieldDescriptor* descriptor,
   (*variables)["enum_verifier"] = type + "_IsValidValue";
   (*variables)["enum_desc_func"] = type + "_EnumDescriptor";
 
+  (*variables)["dataTypeSpecific_name"] = "enumDescFunc";
+  (*variables)["dataTypeSpecific_value"] = (*variables)["enum_desc_func"];
+
   const Descriptor* msg_descriptor = descriptor->containing_type();
   (*variables)["owning_message_class"] = ClassName(msg_descriptor);
 }
@@ -72,13 +75,6 @@ EnumFieldGenerator::EnumFieldGenerator(const FieldDescriptor* descriptor,
 
 EnumFieldGenerator::~EnumFieldGenerator() {}
 
-void EnumFieldGenerator::GenerateFieldDescriptionTypeSpecific(
-    io::Printer* printer) const {
-  printer->Print(
-      variables_,
-      "  .dataTypeSpecific.enumDescFunc = $enum_desc_func$,\n");
-}
-
 void EnumFieldGenerator::GenerateCFunctionDeclarations(
     io::Printer* printer) const {
   if (!HasPreservingUnknownEnumSemantics(descriptor_->file())) {
@@ -87,7 +83,12 @@ void EnumFieldGenerator::GenerateCFunctionDeclarations(
 
   printer->Print(
       variables_,
+      "/// Fetches the raw value of a @c $owning_message_class$'s @c $name$ property, even\n"
+      "/// if the value was not defined by the enum at the time the code was generated.\n"
       "int32_t $owning_message_class$_$capitalized_name$_RawValue($owning_message_class$ *message);\n"
+      "/// Sets the raw value of an @c $owning_message_class$'s @c $name$ property, allowing\n"
+      "/// it to be set to a value that was not defined by the enum at the time the code\n"
+      "/// was generated.\n"
       "void Set$owning_message_class$_$capitalized_name$_RawValue($owning_message_class$ *message, int32_t value);\n"
       "\n");
 }
@@ -140,13 +141,6 @@ void RepeatedEnumFieldGenerator::FinishInitialization(void) {
       "// |" + variables_["name"] + "| contains |" + variables_["storage_type"] + "|\n";
 }
 
-void RepeatedEnumFieldGenerator::GenerateFieldDescriptionTypeSpecific(
-    io::Printer* printer) const {
-  printer->Print(
-      variables_,
-      "  .dataTypeSpecific.enumDescFunc = $enum_desc_func$,\n");
-}
-
 }  // namespace objectivec
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_enum_field.h b/src/google/protobuf/compiler/objectivec/objectivec_enum_field.h
index ae2f57e3..946faa81 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_enum_field.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_enum_field.h
@@ -45,7 +45,6 @@ class EnumFieldGenerator : public SingleFieldGenerator {
                                               const Options& options);
 
  public:
-  virtual void GenerateFieldDescriptionTypeSpecific(io::Printer* printer) const;
   virtual void GenerateCFunctionDeclarations(io::Printer* printer) const;
   virtual void GenerateCFunctionImplementations(io::Printer* printer) const;
   virtual void DetermineForwardDeclarations(set<string>* fwd_decls) const;
@@ -64,7 +63,6 @@ class RepeatedEnumFieldGenerator : public RepeatedFieldGenerator {
 
  public:
   virtual void FinishInitialization();
-  virtual void GenerateFieldDescriptionTypeSpecific(io::Printer* printer) const;
 
  protected:
   RepeatedEnumFieldGenerator(const FieldDescriptor* descriptor,
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_extension.cc b/src/google/protobuf/compiler/objectivec/objectivec_extension.cc
index 4e348393..3f7ab9d3 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_extension.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_extension.cc
@@ -114,14 +114,14 @@ void ExtensionGenerator::GenerateStaticVariablesInitialization(
 
   printer->Print(vars,
                  "{\n"
+                 "  .defaultValue.$default_name$ = $default$,\n"
                  "  .singletonName = GPBStringifySymbol($root_class_and_method_name$),\n"
-                 "  .dataType = $extension_type$,\n"
                  "  .extendedClass = GPBStringifySymbol($extended_type$),\n"
-                 "  .fieldNumber = $number$,\n"
-                 "  .defaultValue.$default_name$ = $default$,\n"
                  "  .messageOrGroupClassName = $type$,\n"
-                 "  .options = $options$,\n"
                  "  .enumDescriptorFunc = $enum_desc_func_name$,\n"
+                 "  .fieldNumber = $number$,\n"
+                 "  .dataType = $extension_type$,\n"
+                 "  .options = $options$,\n"
                  "},\n");
 }
 
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_field.cc b/src/google/protobuf/compiler/objectivec/objectivec_field.cc
index 09341820..7bb9837d 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_field.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_field.cc
@@ -28,6 +28,8 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+#include <iostream>
+
 #include <google/protobuf/compiler/objectivec/objectivec_field.h>
 #include <google/protobuf/compiler/objectivec/objectivec_helpers.h>
 #include <google/protobuf/compiler/objectivec/objectivec_enum_field.h>
@@ -75,7 +77,6 @@ void SetCommonFieldVariables(const FieldDescriptor* descriptor,
   (*variables)["field_number_name"] =
       classname + "_FieldNumber_" + capitalized_name;
   (*variables)["field_number"] = SimpleItoa(descriptor->number());
-  (*variables)["has_index"] = SimpleItoa(descriptor->index());
   (*variables)["field_type"] = GetCapitalizedType(descriptor);
   std::vector<string> field_flags;
   if (descriptor->is_repeated()) field_flags.push_back("GPBFieldRepeated");
@@ -99,18 +100,9 @@ void SetCommonFieldVariables(const FieldDescriptor* descriptor,
   (*variables)["dataTypeSpecific_name"] = "className";
   (*variables)["dataTypeSpecific_value"] = "NULL";
 
-  string field_options = descriptor->options().SerializeAsString();
-  // Must convert to a standard byte order for packing length into
-  // a cstring.
-  uint32 length = ghtonl(field_options.length());
-  if (length > 0) {
-    string bytes((const char*)&length, sizeof(length));
-    bytes.append(field_options);
-    string options_str = "\"" + CEscape(bytes) + "\"";
-    (*variables)["fieldoptions"] = "\"" + CEscape(bytes) + "\"";
-  } else {
-    (*variables)["fieldoptions"] = "";
-  }
+  (*variables)["storage_offset_value"] =
+      "(uint32_t)offsetof(" + classname + "__storage_, " + camel_case_name + ")";
+  (*variables)["storage_offset_comment"] = "";
 
   // Clear some common things so they can be set just when needed.
   (*variables)["storage_attribute"] = "";
@@ -190,52 +182,54 @@ void FieldGenerator::DetermineForwardDeclarations(
 }
 
 void FieldGenerator::GenerateFieldDescription(
-    io::Printer* printer) const {
-  printer->Print(
-      variables_,
-      "{\n"
-      "  .name = \"$name$\",\n"
-      "  .number = $field_number_name$,\n"
-      "  .hasIndex = $has_index$,\n"
-      "  .flags = $fieldflags$,\n"
-      "  .dataType = GPBDataType$field_type$,\n"
-      "  .offset = offsetof($classname$__storage_, $name$),\n"
-      "  .defaultValue.$default_name$ = $default$,\n");
-
-  // TODO(thomasvl): It might be useful to add a CPP wrapper to support
-  // compiling away the EnumDescriptors.  To do that, we'd need a #if here
-  // to control setting the descriptor vs. the validator, and above in
-  // SetCommonFieldVariables() we'd want to wrap how we add
-  // GPBFieldHasDefaultValue to the flags.
-
-  // "  .dataTypeSpecific.value* = [something],"
-  GenerateFieldDescriptionTypeSpecific(printer);
-
-  const string& field_options(variables_.find("fieldoptions")->second);
-  if (field_options.empty()) {
-    printer->Print("  .fieldOptions = NULL,\n");
+    io::Printer* printer, bool include_default) const {
+  // Printed in the same order as the structure decl.
+  if (include_default) {
+    printer->Print(
+        variables_,
+        "{\n"
+        "  .defaultValue.$default_name$ = $default$,\n"
+        "  .core.name = \"$name$\",\n"
+        "  .core.dataTypeSpecific.$dataTypeSpecific_name$ = $dataTypeSpecific_value$,\n"
+        "  .core.number = $field_number_name$,\n"
+        "  .core.hasIndex = $has_index$,\n"
+        "  .core.offset = $storage_offset_value$,$storage_offset_comment$\n"
+        "  .core.flags = $fieldflags$,\n"
+        "  .core.dataType = GPBDataType$field_type$,\n"
+        "},\n");
   } else {
-    // Can't use PrintRaw() here to get the #if/#else/#endif lines completely
-    // outdented because the need for indent captured on the previous
-    // printing of a \n and there is no way to get the current indent level
-    // to call the right number of Outdent()/Indents() to maintain state.
     printer->Print(
         variables_,
-        "#if GPBOBJC_INCLUDE_FIELD_OPTIONS\n"
-        "  .fieldOptions = $fieldoptions$,\n"
-        "#else\n"
-        "  .fieldOptions = NULL,\n"
-        "#endif  // GPBOBJC_INCLUDE_FIELD_OPTIONS\n");
+        "{\n"
+        "  .name = \"$name$\",\n"
+        "  .dataTypeSpecific.$dataTypeSpecific_name$ = $dataTypeSpecific_value$,\n"
+        "  .number = $field_number_name$,\n"
+        "  .hasIndex = $has_index$,\n"
+        "  .offset = $storage_offset_value$,$storage_offset_comment$\n"
+        "  .flags = $fieldflags$,\n"
+        "  .dataType = GPBDataType$field_type$,\n"
+        "},\n");
   }
+}
 
-  printer->Print("},\n");
+void FieldGenerator::SetRuntimeHasBit(int has_index) {
+  variables_["has_index"] = SimpleItoa(has_index);
 }
 
-void FieldGenerator::GenerateFieldDescriptionTypeSpecific(
-    io::Printer* printer) const {
-  printer->Print(
-      variables_,
-      "  .dataTypeSpecific.$dataTypeSpecific_name$ = $dataTypeSpecific_value$,\n");
+void FieldGenerator::SetNoHasBit(void) {
+  variables_["has_index"] = "GPBNoHasBit";
+}
+
+int FieldGenerator::ExtraRuntimeHasBitsNeeded(void) const {
+  return 0;
+}
+
+void FieldGenerator::SetExtraRuntimeHasBitsBase(int index_base) {
+  // 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.
+  cerr << "Error: should have overriden SetExtraRuntimeHasBitsBase()." << endl;
+  cerr.flush();
+  abort();
 }
 
 void FieldGenerator::SetOneofIndexBase(int index_base) {
@@ -270,15 +264,15 @@ void SingleFieldGenerator::GenerateFieldStorageDeclaration(
 void SingleFieldGenerator::GeneratePropertyDeclaration(
     io::Printer* printer) const {
   printer->Print(variables_, "$comments$");
+  printer->Print(
+      variables_,
+      "@property(nonatomic, readwrite) $property_type$ $name$;\n"
+      "\n");
   if (WantsHasProperty()) {
     printer->Print(
         variables_,
         "@property(nonatomic, readwrite) BOOL has$capitalized_name$;\n");
   }
-  printer->Print(
-      variables_,
-      "@property(nonatomic, readwrite) $property_type$ $name$;\n"
-      "\n");
 }
 
 void SingleFieldGenerator::GeneratePropertyImplementation(
@@ -302,6 +296,14 @@ bool SingleFieldGenerator::WantsHasProperty(void) const {
   return false;
 }
 
+bool SingleFieldGenerator::RuntimeUsesHasBit(void) const {
+  if (descriptor_->containing_oneof() != NULL) {
+    // The oneof tracks what is set instead.
+    return false;
+  }
+  return true;
+}
+
 ObjCObjFieldGenerator::ObjCObjFieldGenerator(const FieldDescriptor* descriptor,
                                              const Options& options)
     : SingleFieldGenerator(descriptor, options) {
@@ -326,14 +328,15 @@ void ObjCObjFieldGenerator::GeneratePropertyDeclaration(
   // conventions (init*, new*, etc.)
 
   printer->Print(variables_, "$comments$");
+  printer->Print(
+      variables_,
+      "@property(nonatomic, readwrite, $property_storage_attribute$, null_resettable) $property_type$ *$name$$storage_attribute$;\n");
   if (WantsHasProperty()) {
     printer->Print(
         variables_,
+        "/// Test to see if @c $name$ has been set.\n"
         "@property(nonatomic, readwrite) BOOL has$capitalized_name$;\n");
   }
-  printer->Print(
-      variables_,
-      "@property(nonatomic, readwrite, $property_storage_attribute$, null_resettable) $property_type$ *$name$$storage_attribute$;\n");
   if (IsInitName(variables_.find("name")->second)) {
     // If property name starts with init we need to annotate it to get past ARC.
     // http://stackoverflow.com/questions/18723226/how-do-i-annotate-an-objective-c-property-with-an-objc-method-family/18723227#18723227
@@ -346,8 +349,6 @@ void ObjCObjFieldGenerator::GeneratePropertyDeclaration(
 RepeatedFieldGenerator::RepeatedFieldGenerator(
     const FieldDescriptor* descriptor, const Options& options)
     : ObjCObjFieldGenerator(descriptor, options) {
-  // Repeated fields don't use the has index.
-  variables_["has_index"] = "GPBNoHasBit";
   // Default to no comment and let the cases needing it fill it in.
   variables_["array_comment"] = "";
 }
@@ -385,6 +386,7 @@ void RepeatedFieldGenerator::GeneratePropertyDeclaration(
       "$comments$"
       "$array_comment$"
       "@property(nonatomic, readwrite, strong, null_resettable) $array_property_type$ *$name$$storage_attribute$;\n"
+      "/// The number of items in @c $name$ without causing the array to be created.\n"
       "@property(nonatomic, readonly) NSUInteger $name$_Count;\n");
   if (IsInitName(variables_.find("name")->second)) {
     // If property name starts with init we need to annotate it to get past ARC.
@@ -400,6 +402,10 @@ bool RepeatedFieldGenerator::WantsHasProperty(void) const {
   return false;
 }
 
+bool RepeatedFieldGenerator::RuntimeUsesHasBit(void) const {
+  return false;  // The array having anything is what is used.
+}
+
 FieldGeneratorMap::FieldGeneratorMap(const Descriptor* descriptor,
                                      const Options& options)
     : descriptor_(descriptor),
@@ -430,12 +436,40 @@ const FieldGenerator& FieldGeneratorMap::get_extension(int index) const {
   return *extension_generators_[index];
 }
 
+int FieldGeneratorMap::CalculateHasBits(void) {
+  int total_bits = 0;
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    if (field_generators_[i]->RuntimeUsesHasBit()) {
+      field_generators_[i]->SetRuntimeHasBit(total_bits);
+      ++total_bits;
+    } else {
+      field_generators_[i]->SetNoHasBit();
+    }
+    int extra_bits = field_generators_[i]->ExtraRuntimeHasBitsNeeded();
+    if (extra_bits) {
+      field_generators_[i]->SetExtraRuntimeHasBitsBase(total_bits);
+      total_bits += extra_bits;
+    }
+  }
+  return total_bits;
+}
+
 void FieldGeneratorMap::SetOneofIndexBase(int index_base) {
   for (int i = 0; i < descriptor_->field_count(); i++) {
     field_generators_[i]->SetOneofIndexBase(index_base);
   }
 }
 
+bool FieldGeneratorMap::DoesAnyFieldHaveNonZeroDefault(void) const {
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    if (HasNonZeroDefaultValue(descriptor_->field(i))) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
 }  // namespace objectivec
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_field.h b/src/google/protobuf/compiler/objectivec/objectivec_field.h
index e8a20a72..a3a4b1b6 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_field.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_field.h
@@ -61,7 +61,6 @@ class FieldGenerator {
 
   // Called by GenerateFieldDescription, exposed for classes that need custom
   // generation.
-  virtual void GenerateFieldDescriptionTypeSpecific(io::Printer* printer) const;
 
   // Exposed for subclasses to extend, base does nothing.
   virtual void GenerateCFunctionDeclarations(io::Printer* printer) const;
@@ -71,9 +70,16 @@ class FieldGenerator {
   virtual void DetermineForwardDeclarations(set<string>* fwd_decls) const;
 
   // Used during generation, not intended to be extended by subclasses.
-  void GenerateFieldDescription(io::Printer* printer) const;
+  void GenerateFieldDescription(
+      io::Printer* printer, bool include_default) const;
   void GenerateFieldNumberConstant(io::Printer* printer) const;
 
+  // Exposed to get and set the has bits information.
+  virtual bool RuntimeUsesHasBit(void) const = 0;
+  void SetRuntimeHasBit(int has_index);
+  void SetNoHasBit(void);
+  virtual int ExtraRuntimeHasBitsNeeded(void) const;
+  virtual void SetExtraRuntimeHasBitsBase(int index_base);
   void SetOneofIndexBase(int index_base);
 
   string variable(const char* key) const {
@@ -109,6 +115,8 @@ class SingleFieldGenerator : public FieldGenerator {
 
   virtual void GeneratePropertyImplementation(io::Printer* printer) const;
 
+  virtual bool RuntimeUsesHasBit(void) const;
+
  protected:
   SingleFieldGenerator(const FieldDescriptor* descriptor,
                        const Options& options);
@@ -143,6 +151,8 @@ class RepeatedFieldGenerator : public ObjCObjFieldGenerator {
 
   virtual void GeneratePropertyImplementation(io::Printer* printer) const;
 
+  virtual bool RuntimeUsesHasBit(void) const;
+
  protected:
   RepeatedFieldGenerator(const FieldDescriptor* descriptor,
                          const Options& options);
@@ -162,8 +172,14 @@ class FieldGeneratorMap {
   const FieldGenerator& get(const FieldDescriptor* field) const;
   const FieldGenerator& get_extension(int index) const;
 
+  // Assigns the has bits and returns the number of bits needed.
+  int CalculateHasBits(void);
+
   void SetOneofIndexBase(int index_base);
 
+  // Check if any field of this message has a non zero default.
+  bool DoesAnyFieldHaveNonZeroDefault(void) const;
+
  private:
   const Descriptor* descriptor_;
   scoped_array<scoped_ptr<FieldGenerator> > field_generators_;
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_file.cc b/src/google/protobuf/compiler/objectivec/objectivec_file.cc
index cdf9ebbc..c58e7530 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_file.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_file.cc
@@ -45,7 +45,7 @@ namespace protobuf {
 // This is also found in GPBBootstrap.h, and needs to be kept in sync.  It
 // is the version check done to ensure generated code works with the current
 // runtime being used.
-const int32 GOOGLE_PROTOBUF_OBJC_GEN_VERSION = 30000;
+const int32 GOOGLE_PROTOBUF_OBJC_GEN_VERSION = 30001;
 
 namespace compiler {
 namespace objectivec {
@@ -151,13 +151,15 @@ void FileGenerator::GenerateHeader(io::Printer *printer) {
   printer->Print(
       "#pragma mark - $root_class_name$\n"
       "\n"
+      "/// Exposes the extension registry for this file.\n"
+      "///\n"
+      "/// The base class provides:\n"
+      "/// @code\n"
+      "///   + (GPBExtensionRegistry *)extensionRegistry;\n"
+      "/// @endcode\n"
+      "/// which is a @c GPBExtensionRegistry that includes all the extensions defined by\n"
+      "/// this file and all files that it depends on.\n"
       "@interface $root_class_name$ : GPBRootObject\n"
-      "\n"
-      "// The base class provides:\n"
-      "//   + (GPBExtensionRegistry *)extensionRegistry;\n"
-      "// which is an GPBExtensionRegistry that includes all the extensions defined by\n"
-      "// this file and all files that it depends on.\n"
-      "\n"
       "@end\n"
       "\n",
       "root_class_name", root_class_name_);
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc b/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc
index 77a378c8..fda51807 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc
@@ -124,9 +124,14 @@ string UnderscoresToCamelCase(const string& input, bool first_capitalized) {
   }
   values.push_back(current);
 
+  string result;
+  bool first_segment_forces_upper = false;
   for (vector<string>::iterator i = values.begin(); i != values.end(); ++i) {
     string value = *i;
     bool all_upper = (kUpperSegments.count(value) > 0);
+    if (all_upper && (result.length() == 0)) {
+      first_segment_forces_upper = true;
+    }
     for (int j = 0; j < value.length(); j++) {
       if (j == 0 || all_upper) {
         value[j] = ascii_toupper(value[j]);
@@ -134,13 +139,11 @@ string UnderscoresToCamelCase(const string& input, bool first_capitalized) {
         // Nothing, already in lower.
       }
     }
-    *i = value;
-  }
-  string result;
-  for (vector<string>::iterator i = values.begin(); i != values.end(); ++i) {
-    result += *i;
+    result += value;
   }
-  if ((result.length() != 0) && !first_capitalized) {
+  if ((result.length() != 0) &&
+      !first_capitalized &&
+      !first_segment_forces_upper) {
     result[0] = ascii_tolower(result[0]);
   }
   return result;
@@ -217,11 +220,6 @@ string NameFromFieldDescriptor(const FieldDescriptor* field) {
   }
 }
 
-// Escape C++ trigraphs by escaping question marks to \?
-string EscapeTrigraphs(const string& to_escape) {
-  return StringReplace(to_escape, "?", "\\?", true);
-}
-
 void PathSplit(const string& path, string* directory, string* basename) {
   string::size_type last_slash = path.rfind('/');
   if (last_slash == string::npos) {
@@ -261,6 +259,11 @@ bool IsSpecialName(const string& name, const string* special_names,
 
 }  // namespace
 
+// Escape C++ trigraphs by escaping question marks to \?
+string EscapeTrigraphs(const string& to_escape) {
+  return StringReplace(to_escape, "?", "\\?", true);
+}
+
 string StripProto(const string& filename) {
   if (HasSuffixString(filename, ".protodevel")) {
     return StripSuffixString(filename, ".protodevel");
@@ -731,7 +734,7 @@ string DefaultValue(const FieldDescriptor* field) {
         uint32 length = ghtonl(default_string.length());
         string bytes((const char*)&length, sizeof(length));
         bytes.append(default_string);
-        return "(NSData*)\"" + CEscape(bytes) + "\"";
+        return "(NSData*)\"" + EscapeTrigraphs(CEscape(bytes)) + "\"";
       } else {
         return "@\"" + EscapeTrigraphs(CEscape(default_string)) + "\"";
       }
@@ -748,6 +751,50 @@ string DefaultValue(const FieldDescriptor* field) {
   return NULL;
 }
 
+bool HasNonZeroDefaultValue(const FieldDescriptor* field) {
+  // Repeated fields don't have defaults.
+  if (field->is_repeated()) {
+    return false;
+  }
+
+  if (!field->has_default_value()) {
+    // No custom default set in the proto file.
+    return false;
+  }
+
+  // Some proto file set the default to the zero value, so make sure the value
+  // isn't the zero case.
+  switch (field->cpp_type()) {
+    case FieldDescriptor::CPPTYPE_INT32:
+      return field->default_value_int32() != 0;
+    case FieldDescriptor::CPPTYPE_UINT32:
+      return field->default_value_uint32() != 0U;
+    case FieldDescriptor::CPPTYPE_INT64:
+      return field->default_value_int64() != 0LL;
+    case FieldDescriptor::CPPTYPE_UINT64:
+      return field->default_value_uint64() != 0ULL;
+    case FieldDescriptor::CPPTYPE_DOUBLE:
+      return field->default_value_double() != 0.0;
+    case FieldDescriptor::CPPTYPE_FLOAT:
+      return field->default_value_float() != 0.0f;
+    case FieldDescriptor::CPPTYPE_BOOL:
+      return field->default_value_bool();
+    case FieldDescriptor::CPPTYPE_STRING: {
+      const string& default_string = field->default_value_string();
+      return default_string.length() != 0;
+    }
+    case FieldDescriptor::CPPTYPE_ENUM:
+      return field->default_value_enum()->number() != 0;
+    case FieldDescriptor::CPPTYPE_MESSAGE:
+      return false;
+  }
+
+  // Some compilers report reaching end of function even though all cases of
+  // the enum are handed in the switch.
+  GOOGLE_LOG(FATAL) << "Can't get here.";
+  return false;
+}
+
 string BuildFlagsString(const vector<string>& strings) {
   if (strings.size() == 0) {
     return "0";
@@ -771,16 +818,14 @@ string BuildCommentsString(const SourceLocation& location) {
   while (!lines.empty() && lines.back().empty()) {
     lines.pop_back();
   }
-  string prefix("//");
+  string prefix("///");
   string suffix("\n");
   string final_comments;
   for (int i = 0; i < lines.size(); i++) {
-    // We use $ for delimiters, so replace comments with dollars with
-    // html escaped version.
-    // None of the other compilers handle this (as of this writing) but we
-    // ran into it once, so just to be safe.
+    // HeaderDoc uses '\' and '@' for markers; escape them.
+    const string line = StringReplace(lines[i], "\\", "\\\\", true);
     final_comments +=
-        prefix + StringReplace(lines[i], "$", "&#36;", true) + suffix;
+        prefix + StringReplace(line, "@", "\\@", true) + suffix;
   }
   return final_comments;
 }
@@ -968,7 +1013,8 @@ bool ValidateObjCClassPrefix(const FileDescriptor* file,
     } else {
       // ...it didn't match!
       *out_error = "error: Expected 'option objc_class_prefix = \"" +
-                   package_match->second + "\";' in '" + file->name() + "'";
+                   package_match->second + "\";' for package '" + package +
+                   "' in '" + file->name() + "'";
       if (prefix.length()) {
         *out_error += "; but found '" + prefix + "' instead";
       }
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_helpers.h b/src/google/protobuf/compiler/objectivec/objectivec_helpers.h
index 5b2dd190..0db9de94 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_helpers.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_helpers.h
@@ -48,6 +48,9 @@ struct Options {
   string expected_prefixes_path;
 };
 
+// Escape C++ trigraphs by escaping question marks to "\?".
+string EscapeTrigraphs(const string& to_escape);
+
 // Strips ".proto" or ".protodevel" from the end of a filename.
 string StripProto(const string& filename);
 
@@ -143,9 +146,11 @@ bool IsReferenceType(const FieldDescriptor* field);
 
 string GPBGenericValueFieldName(const FieldDescriptor* field);
 string DefaultValue(const FieldDescriptor* field);
+bool HasNonZeroDefaultValue(const FieldDescriptor* field);
 
 string BuildFlagsString(const vector<string>& strings);
 
+// Builds a HeaderDoc style comment out of the comments in the .proto file.
 string BuildCommentsString(const SourceLocation& location);
 
 // Checks the prefix for a given file and outputs any warnings needed, if
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_map_field.cc b/src/google/protobuf/compiler/objectivec/objectivec_map_field.cc
index 2751e936..ac5d8aea 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_map_field.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_map_field.cc
@@ -140,13 +140,18 @@ MapFieldGenerator::MapFieldGenerator(const FieldDescriptor* descriptor,
           value_field_generator_->variable("storage_type") + "*>";
     }
   }
+
+  variables_["dataTypeSpecific_name"] =
+      value_field_generator_->variable("dataTypeSpecific_name");
+  variables_["dataTypeSpecific_value"] =
+      value_field_generator_->variable("dataTypeSpecific_value");
 }
 
 MapFieldGenerator::~MapFieldGenerator() {}
 
 void MapFieldGenerator::FinishInitialization(void) {
   RepeatedFieldGenerator::FinishInitialization();
-  // Use the array_comment suport in RepeatedFieldGenerator to output what the
+  // Use the array_comment support in RepeatedFieldGenerator to output what the
   // values in the map are.
   const FieldDescriptor* value_descriptor =
       descriptor_->message_type()->FindFieldByName("value");
@@ -156,13 +161,6 @@ void MapFieldGenerator::FinishInitialization(void) {
   }
 }
 
-void MapFieldGenerator::GenerateFieldDescriptionTypeSpecific(
-    io::Printer* printer) const {
-  // Relay it to the value generator to provide enum validator, message
-  // class, etc.
-  value_field_generator_->GenerateFieldDescriptionTypeSpecific(printer);
-}
-
 void MapFieldGenerator::DetermineForwardDeclarations(
     set<string>* fwd_decls) const {
   RepeatedFieldGenerator::DetermineForwardDeclarations(fwd_decls);
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_map_field.h b/src/google/protobuf/compiler/objectivec/objectivec_map_field.h
index 7351ea05..bc68a682 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_map_field.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_map_field.h
@@ -46,7 +46,6 @@ class MapFieldGenerator : public RepeatedFieldGenerator {
 
  public:
   virtual void FinishInitialization(void);
-  virtual void GenerateFieldDescriptionTypeSpecific(io::Printer* printer) const;
 
  protected:
   MapFieldGenerator(const FieldDescriptor* descriptor, const Options& options);
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_message.cc b/src/google/protobuf/compiler/objectivec/objectivec_message.cc
index e0ea8bd2..3ebeeade 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_message.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_message.cc
@@ -66,11 +66,12 @@ int OrderGroupForFieldDescriptor(const FieldDescriptor* descriptor) {
   // The first item in the object structure is our uint32[] for has bits.
   // We then want to order things to make the instances as small as
   // possible. So we follow the has bits with:
-  //   1. Bools (1 byte)
-  //   2. Anything always 4 bytes - float, *32, enums
-  //   3. Anything that is always a pointer (they will be 8 bytes on 64 bit
+  //   1. Anything always 4 bytes - float, *32, enums
+  //   2. Anything that is always a pointer (they will be 8 bytes on 64 bit
   //      builds and 4 bytes on 32bit builds.
-  //   4. Anything always 8 bytes - double, *64
+  //   3. Anything always 8 bytes - double, *64
+  //
+  // NOTE: Bools aren't listed, they were stored in the has bits.
   //
   // Why? Using 64bit builds as an example, this means worse case, we have
   // enough bools that we overflow 1 byte from 4 byte alignment, so 3 bytes
@@ -115,9 +116,9 @@ int OrderGroupForFieldDescriptor(const FieldDescriptor* descriptor) {
     case FieldDescriptor::TYPE_ENUM:
       return 2;
 
-    // 1 byte.
+    // 0 bytes. Stored in the has bits.
     case FieldDescriptor::TYPE_BOOL:
-      return 1;
+      return 99;  // End of the list (doesn't really matter).
   }
 
   // Some compilers report reaching end of function even though all cases of
@@ -404,32 +405,28 @@ void MessageGenerator::GenerateSource(io::Printer* printer) {
     sort(sorted_extensions.begin(), sorted_extensions.end(),
          ExtensionRangeOrdering());
 
-    // TODO(thomasvl): Finish optimizing has bit. The current behavior is as
-    // follows:
-    // 1. objectivec_field.cc's SetCommonFieldVariables() defaults the has_index
-    //    to the field's index in the list of fields.
-    // 2. RepeatedFieldGenerator::RepeatedFieldGenerator() sets has_index to
-    //    GPBNoHasBit because repeated fields & map<> fields don't use the has
-    //    bit.
-    // 3. FieldGenerator::SetOneofIndexBase() overrides has_bit with a negative
-    //    index that groups all the elements on of the oneof.
-    // So in has_storage, we need enough bits for the single fields that aren't
-    // in any oneof, and then one int32 for each oneof (to store the field
-    // number).  So we could save a little space by not using the field's index
-    // and instead make a second pass only assigning indexes for the fields
-    // that would need it.  The only savings would come when messages have over
-    // a multiple of 32 fields with some number being repeated or in oneofs to
-    // drop the count below that 32 multiple; so it hasn't seemed worth doing
-    // at the moment.
-    size_t num_has_bits = descriptor_->field_count();
+    // Assign has bits:
+    // 1. FieldGeneratorMap::CalculateHasBits() loops through the fields seeing
+    //    who needs has bits and assigning them.
+    // 2. FieldGenerator::SetOneofIndexBase() overrides has_bit with a negative
+    //    index that groups all the elements in the oneof.
+    size_t num_has_bits = field_generators_.CalculateHasBits();
     size_t sizeof_has_storage = (num_has_bits + 31) / 32;
+    if (sizeof_has_storage == 0) {
+      // In the case where no field needs has bits, don't let the _has_storage_
+      // end up as zero length (zero length arrays are sort of a grey area
+      // since it has to be at the start of the struct). This also ensures a
+      // field with only oneofs keeps the required negative indices they need.
+      sizeof_has_storage = 1;
+    }
     // Tell all the fields the oneof base.
     for (vector<OneofGenerator*>::iterator iter = oneof_generators_.begin();
          iter != oneof_generators_.end(); ++iter) {
       (*iter)->SetOneofIndexBase(sizeof_has_storage);
     }
     field_generators_.SetOneofIndexBase(sizeof_has_storage);
-    // Add an int32 for each oneof to store which is set.
+    // sizeof_has_storage needs enough bits for the single fields that aren't in
+    // any oneof, and then one int32 for each oneof (to store the field number).
     sizeof_has_storage += descriptor_->oneof_decl_count();
 
     printer->Print(
@@ -456,47 +453,26 @@ void MessageGenerator::GenerateSource(io::Printer* printer) {
         "  static GPBDescriptor *descriptor = nil;\n"
         "  if (!descriptor) {\n");
 
-    bool has_oneofs = oneof_generators_.size();
-    if (has_oneofs) {
-      printer->Print(
-          "    static GPBMessageOneofDescription oneofs[] = {\n");
-      printer->Indent();
-      printer->Indent();
-      printer->Indent();
-      for (vector<OneofGenerator*>::iterator iter = oneof_generators_.begin();
-           iter != oneof_generators_.end(); ++iter) {
-        (*iter)->GenerateDescription(printer);
-      }
-      printer->Outdent();
-      printer->Outdent();
-      printer->Outdent();
-      printer->Print(
-          "    };\n");
-    }
-
     TextFormatDecodeData text_format_decode_data;
     bool has_fields = descriptor_->field_count() > 0;
+    bool need_defaults = field_generators_.DoesAnyFieldHaveNonZeroDefault();
+    string field_description_type;
+    if (need_defaults) {
+      field_description_type = "GPBMessageFieldDescriptionWithDefault";
+    } else {
+      field_description_type = "GPBMessageFieldDescription";
+    }
     if (has_fields) {
-      // TODO(thomasvl): The plugin's FieldGenerator::GenerateFieldDescription()
-      // wraps the fieldOptions's value of this structure in an CPP gate so
-      // they can be compiled away; but that still results in a const char* in
-      // the structure for a NULL pointer for every message field.  If the
-      // fieldOptions are moved to a separate payload like the TextFormat extra
-      // data is, then it would shrink that static data shrinking the binaries
-      // a little more.
-      // TODO(thomasvl): proto3 syntax doens't need a defaultValue in the
-      // structure because primitive types are always zero.  If we add a second
-      // structure and a different initializer, we can avoid the wasted static
-      // storage for every field in a proto3 message.
       printer->Print(
-          "    static GPBMessageFieldDescription fields[] = {\n");
+          "    static $field_description_type$ fields[] = {\n",
+          "field_description_type", field_description_type);
       printer->Indent();
       printer->Indent();
       printer->Indent();
       for (int i = 0; i < descriptor_->field_count(); ++i) {
         const FieldGenerator& field_generator =
             field_generators_.get(sorted_fields[i]);
-        field_generator.GenerateFieldDescription(printer);
+        field_generator.GenerateFieldDescription(printer, need_defaults);
         if (field_generator.needs_textformat_name_support()) {
           text_format_decode_data.AddString(sorted_fields[i]->number(),
                                             field_generator.generated_objc_name(),
@@ -510,111 +486,89 @@ void MessageGenerator::GenerateSource(io::Printer* printer) {
           "    };\n");
     }
 
-    bool has_enums = enum_generators_.size();
-    if (has_enums) {
+    map<string, string> vars;
+    vars["classname"] = class_name_;
+    vars["rootclassname"] = root_classname_;
+    vars["fields"] = has_fields ? "fields" : "NULL";
+    if (has_fields) {
+      vars["fields_count"] =
+          "(uint32_t)(sizeof(fields) / sizeof(" + field_description_type + "))";
+    } else {
+      vars["fields_count"] = "0";
+    }
+
+    std::vector<string> init_flags;
+    if (need_defaults) {
+      init_flags.push_back("GPBDescriptorInitializationFlag_FieldsWithDefault");
+    }
+    if (descriptor_->options().message_set_wire_format()) {
+      init_flags.push_back("GPBDescriptorInitializationFlag_WireFormat");
+    }
+    vars["init_flags"] = BuildFlagsString(init_flags);
+
+    printer->Print(
+        vars,
+        "    GPBDescriptor *localDescriptor =\n"
+        "        [GPBDescriptor allocDescriptorForClass:[$classname$ class]\n"
+        "                                     rootClass:[$rootclassname$ class]\n"
+        "                                          file:$rootclassname$_FileDescriptor()\n"
+        "                                        fields:$fields$\n"
+        "                                    fieldCount:$fields_count$\n"
+        "                                   storageSize:sizeof($classname$__storage_)\n"
+        "                                         flags:$init_flags$];\n");
+    if (oneof_generators_.size() != 0) {
       printer->Print(
-          "    static GPBMessageEnumDescription enums[] = {\n");
-      printer->Indent();
-      printer->Indent();
-      printer->Indent();
-      for (vector<EnumGenerator*>::iterator iter = enum_generators_.begin();
-           iter != enum_generators_.end(); ++iter) {
-        printer->Print("{ .enumDescriptorFunc = $name$_EnumDescriptor },\n",
-                       "name", (*iter)->name());
+          "    static const char *oneofs[] = {\n");
+      for (vector<OneofGenerator*>::iterator iter = oneof_generators_.begin();
+           iter != oneof_generators_.end(); ++iter) {
+        printer->Print(
+            "      \"$name$\",\n",
+            "name", (*iter)->DescriptorName());
       }
-      printer->Outdent();
-      printer->Outdent();
-      printer->Outdent();
       printer->Print(
-          "    };\n");
+          "    };\n"
+          "    [localDescriptor setupOneofs:oneofs\n"
+          "                           count:(uint32_t)(sizeof(oneofs) / sizeof(char*))\n"
+          "                   firstHasIndex:$first_has_index$];\n",
+          "first_has_index", oneof_generators_[0]->HasIndexAsString());
     }
-
-    bool has_extensions = sorted_extensions.size();
-    if (has_extensions) {
+    if (text_format_decode_data.num_entries() != 0) {
+      const string text_format_data_str(text_format_decode_data.Data());
       printer->Print(
-          "    static GPBExtensionRange ranges[] = {\n");
-      printer->Indent();
-      printer->Indent();
-      printer->Indent();
-      for (int i = 0; i < sorted_extensions.size(); i++) {
-        printer->Print("{ .start = $start$, .end = $end$ },\n",
-                       "start", SimpleItoa(sorted_extensions[i]->start),
-                       "end", SimpleItoa(sorted_extensions[i]->end));
+          "#if !GPBOBJC_SKIP_MESSAGE_TEXTFORMAT_EXTRAS\n"
+          "    static const char *extraTextFormatInfo =");
+      static const int kBytesPerLine = 40;  // allow for escaping
+      for (int i = 0; i < text_format_data_str.size(); i += kBytesPerLine) {
+        printer->Print(
+            "\n        \"$data$\"",
+            "data", EscapeTrigraphs(
+                CEscape(text_format_data_str.substr(i, kBytesPerLine))));
       }
-      printer->Outdent();
-      printer->Outdent();
-      printer->Outdent();
       printer->Print(
-          "    };\n");
+          ";\n"
+          "    [localDescriptor setupExtraTextInfo:extraTextFormatInfo];\n"
+          "#endif  // !GPBOBJC_SKIP_MESSAGE_TEXTFORMAT_EXTRAS\n");
     }
-
-    map<string, string> vars;
-    vars["classname"] = class_name_;
-    vars["rootclassname"] = root_classname_;
-    vars["fields"] = has_fields ? "fields" : "NULL";
-    vars["fields_count"] =
-        has_fields ? "sizeof(fields) / sizeof(GPBMessageFieldDescription)" : "0";
-    vars["oneofs"] = has_oneofs ? "oneofs" : "NULL";
-    vars["oneof_count"] =
-        has_oneofs ? "sizeof(oneofs) / sizeof(GPBMessageOneofDescription)" : "0";
-    vars["enums"] = has_enums ? "enums" : "NULL";
-    vars["enum_count"] =
-        has_enums ? "sizeof(enums) / sizeof(GPBMessageEnumDescription)" : "0";
-    vars["ranges"] = has_extensions ? "ranges" : "NULL";
-    vars["range_count"] =
-        has_extensions ? "sizeof(ranges) / sizeof(GPBExtensionRange)" : "0";
-    vars["wireformat"] =
-        descriptor_->options().message_set_wire_format() ? "YES" : "NO";
-
-    if (text_format_decode_data.num_entries() == 0) {
+    if (sorted_extensions.size() != 0) {
       printer->Print(
-          vars,
-          "    GPBDescriptor *localDescriptor =\n"
-          "        [GPBDescriptor allocDescriptorForClass:[$classname$ class]\n"
-          "                                     rootClass:[$rootclassname$ class]\n"
-          "                                          file:$rootclassname$_FileDescriptor()\n"
-          "                                        fields:$fields$\n"
-          "                                    fieldCount:$fields_count$\n"
-          "                                        oneofs:$oneofs$\n"
-          "                                    oneofCount:$oneof_count$\n"
-          "                                         enums:$enums$\n"
-          "                                     enumCount:$enum_count$\n"
-          "                                        ranges:$ranges$\n"
-          "                                    rangeCount:$range_count$\n"
-          "                                   storageSize:sizeof($classname$__storage_)\n"
-          "                                    wireFormat:$wireformat$];\n");
-    } else {
-      vars["extraTextFormatInfo"] = CEscape(text_format_decode_data.Data());
-      printer->Print(
-          vars,
-          "#if GPBOBJC_SKIP_MESSAGE_TEXTFORMAT_EXTRAS\n"
-          "    const char *extraTextFormatInfo = NULL;\n"
-          "#else\n"
-          "    static const char *extraTextFormatInfo = \"$extraTextFormatInfo$\";\n"
-          "#endif  // GPBOBJC_SKIP_MESSAGE_TEXTFORMAT_EXTRAS\n"
-          "    GPBDescriptor *localDescriptor =\n"
-          "        [GPBDescriptor allocDescriptorForClass:[$classname$ class]\n"
-          "                                     rootClass:[$rootclassname$ class]\n"
-          "                                          file:$rootclassname$_FileDescriptor()\n"
-          "                                        fields:$fields$\n"
-          "                                    fieldCount:$fields_count$\n"
-          "                                        oneofs:$oneofs$\n"
-          "                                    oneofCount:$oneof_count$\n"
-          "                                         enums:$enums$\n"
-          "                                     enumCount:$enum_count$\n"
-          "                                        ranges:$ranges$\n"
-          "                                    rangeCount:$range_count$\n"
-          "                                   storageSize:sizeof($classname$__storage_)\n"
-          "                                    wireFormat:$wireformat$\n"
-          "                           extraTextFormatInfo:extraTextFormatInfo];\n");
+          "    static const GPBExtensionRange ranges[] = {\n");
+      for (int i = 0; i < sorted_extensions.size(); i++) {
+        printer->Print("      { .start = $start$, .end = $end$ },\n",
+                       "start", SimpleItoa(sorted_extensions[i]->start),
+                       "end", SimpleItoa(sorted_extensions[i]->end));
       }
       printer->Print(
-          "    NSAssert(descriptor == nil, @\"Startup recursed!\");\n"
-          "    descriptor = localDescriptor;\n"
-          "  }\n"
-          "  return descriptor;\n"
-          "}\n\n"
-          "@end\n\n");
+          "    };\n"
+          "    [localDescriptor setupExtensionRanges:ranges\n"
+          "                                    count:(uint32_t)(sizeof(ranges) / sizeof(GPBExtensionRange))];\n");
+    }
+    printer->Print(
+        "    NSAssert(descriptor == nil, @\"Startup recursed!\");\n"
+        "    descriptor = localDescriptor;\n"
+        "  }\n"
+        "  return descriptor;\n"
+        "}\n\n"
+        "@end\n\n");
 
     for (int i = 0; i < descriptor_->field_count(); i++) {
       field_generators_.get(descriptor_->field(i))
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_oneof.cc b/src/google/protobuf/compiler/objectivec/objectivec_oneof.cc
index 3cb87482..44bafd7f 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_oneof.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_oneof.cc
@@ -104,6 +104,7 @@ void OneofGenerator::GeneratePublicCasePropertyDeclaration(
 void OneofGenerator::GenerateClearFunctionDeclaration(io::Printer* printer) {
   printer->Print(
       variables_,
+      "/// Clears whatever value was set for the oneof '$name$'.\n"
       "void $owning_message_class$_Clear$capitalized_name$OneOfCase($owning_message_class$ *message);\n");
 }
 
@@ -119,17 +120,16 @@ void OneofGenerator::GenerateClearFunctionImplementation(io::Printer* printer) {
       "void $owning_message_class$_Clear$capitalized_name$OneOfCase($owning_message_class$ *message) {\n"
       "  GPBDescriptor *descriptor = [message descriptor];\n"
       "  GPBOneofDescriptor *oneof = descriptor->oneofs_[$raw_index$];\n"
-      "  GPBMaybeClearOneof(message, oneof, 0);\n"
+      "  GPBMaybeClearOneof(message, oneof, $index$, 0);\n"
       "}\n");
 }
 
-void OneofGenerator::GenerateDescription(io::Printer* printer) {
-  printer->Print(
-      variables_,
-      "{\n"
-      "  .name = \"$name$\",\n"
-      "  .index = $index$,\n"
-      "},\n");
+string OneofGenerator::DescriptorName(void) const {
+  return variables_.find("name")->second;
+}
+
+string OneofGenerator::HasIndexAsString(void) const {
+  return variables_.find("index")->second;
 }
 
 }  // namespace objectivec
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_oneof.h b/src/google/protobuf/compiler/objectivec/objectivec_oneof.h
index bcba82da..3d9df4db 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_oneof.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_oneof.h
@@ -61,7 +61,9 @@ class OneofGenerator {
 
   void GeneratePropertyImplementation(io::Printer* printer);
   void GenerateClearFunctionImplementation(io::Printer* printer);
-  void GenerateDescription(io::Printer* printer);
+
+  string DescriptorName(void) const;
+  string HasIndexAsString(void) const;
 
  private:
   const OneofDescriptor* descriptor_;
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.cc b/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.cc
index ea7f1b91..d49350f4 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.cc
@@ -134,6 +134,32 @@ PrimitiveFieldGenerator::PrimitiveFieldGenerator(
 
 PrimitiveFieldGenerator::~PrimitiveFieldGenerator() {}
 
+void PrimitiveFieldGenerator::GenerateFieldStorageDeclaration(
+    io::Printer* printer) const {
+  if (GetObjectiveCType(descriptor_) == OBJECTIVECTYPE_BOOLEAN) {
+    // Nothing, BOOLs are stored in the has bits.
+  } else {
+    SingleFieldGenerator::GenerateFieldStorageDeclaration(printer);
+  }
+}
+
+int PrimitiveFieldGenerator::ExtraRuntimeHasBitsNeeded(void) const {
+  if (GetObjectiveCType(descriptor_) == OBJECTIVECTYPE_BOOLEAN) {
+    // Reserve a bit for the storage of the boolean.
+    return 1;
+  }
+  return 0;
+}
+
+void PrimitiveFieldGenerator::SetExtraRuntimeHasBitsBase(int has_base) {
+  if (GetObjectiveCType(descriptor_) == OBJECTIVECTYPE_BOOLEAN) {
+    // Set into the offset the has bit to use for the actual value.
+    variables_["storage_offset_value"] = SimpleItoa(has_base);
+    variables_["storage_offset_comment"] =
+        "  // Stored in _has_storage_ to save space.";
+  }
+}
+
 PrimitiveObjFieldGenerator::PrimitiveObjFieldGenerator(
     const FieldDescriptor* descriptor, const Options& options)
     : ObjCObjFieldGenerator(descriptor, options) {
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.h b/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.h
index 87139afb..69bb1fdd 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.h
@@ -49,6 +49,11 @@ class PrimitiveFieldGenerator : public SingleFieldGenerator {
                           const Options& options);
   virtual ~PrimitiveFieldGenerator();
 
+  virtual void GenerateFieldStorageDeclaration(io::Printer* printer) const;
+
+  virtual int ExtraRuntimeHasBitsNeeded(void) const;
+  virtual void SetExtraRuntimeHasBitsBase(int index_base);
+
  private:
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(PrimitiveFieldGenerator);
 };
diff --git a/src/google/protobuf/compiler/ruby/ruby_generator.cc b/src/google/protobuf/compiler/ruby/ruby_generator.cc
index 9692f1bf..92c76fb0 100644
--- a/src/google/protobuf/compiler/ruby/ruby_generator.cc
+++ b/src/google/protobuf/compiler/ruby/ruby_generator.cc
@@ -75,6 +75,10 @@ std::string StripDotProto(const std::string& proto_file) {
   return proto_file.substr(0, lastindex);
 }
 
+std::string GetOutputFilename(const std::string& proto_file) {
+  return StripDotProto(proto_file) + ".rb";
+}
+
 std::string LabelForField(const google::protobuf::FieldDescriptor* field) {
   switch (field->label()) {
     case FieldDescriptor::LABEL_OPTIONAL: return "optional";
@@ -331,8 +335,69 @@ void EndPackageModules(
   }
 }
 
-void GenerateFile(const google::protobuf::FileDescriptor* file,
-                  google::protobuf::io::Printer* printer) {
+bool UsesTypeFromFile(const Descriptor* message, const FileDescriptor* file,
+                      string* error) {
+  for (int i = 0; i < message->field_count(); i++) {
+    const FieldDescriptor* field = message->field(i);
+    if ((field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE &&
+         field->message_type()->file() == file) ||
+        (field->type() == FieldDescriptor::TYPE_ENUM &&
+         field->enum_type()->file() == file)) {
+      *error = "proto3 message field " + field->full_name() + " in file " +
+               file->name() + " has a dependency on a type from proto2 file " +
+               file->name() +
+               ".  Ruby doesn't support proto2 yet, so we must fail.";
+      return true;
+    }
+  }
+
+  for (int i = 0; i < message->nested_type_count(); i++) {
+    if (UsesTypeFromFile(message->nested_type(i), file, error)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+// Ruby doesn't currently support proto2.  This causes a failure even for proto3
+// files that import proto2.  But in some cases, the proto2 file is only being
+// imported to extend another proto2 message.  The prime example is declaring
+// custom options by extending FileOptions/FieldOptions/etc.
+//
+// If the proto3 messages don't have any proto2 submessages, it is safe to omit
+// the dependency completely.  Users won't be able to use any proto2 extensions,
+// but they already couldn't because proto2 messages aren't supported.
+//
+// If/when we add proto2 support, we should remove this.
+bool MaybeEmitDependency(const FileDescriptor* import,
+                         const FileDescriptor* from,
+                         io::Printer* printer,
+                         string* error) {
+  if (import->syntax() == FileDescriptor::SYNTAX_PROTO2) {
+    for (int i = 0; i < from->message_type_count(); i++) {
+      if (UsesTypeFromFile(from->message_type(i), import, error)) {
+        // Error text was already set by UsesTypeFromFile().
+        return false;
+      }
+    }
+
+    // Ok to omit this proto2 dependency -- so we won't print anything.
+    GOOGLE_LOG(WARNING) << "Omitting proto2 dependency '" << import->name()
+                        << "' from proto3 output file '"
+                        << GetOutputFilename(from->name())
+                        << "' because we don't support proto2 and no proto2 "
+                           "types from that file are being used.";
+    return true;
+  } else {
+    printer->Print(
+      "require '$name$'\n", "name", StripDotProto(import->name()));
+    return true;
+  }
+}
+
+bool GenerateFile(const FileDescriptor* file, io::Printer* printer,
+                  string* error) {
   printer->Print(
     "# Generated by the protocol buffer compiler.  DO NOT EDIT!\n"
     "# source: $filename$\n"
@@ -343,9 +408,9 @@ void GenerateFile(const google::protobuf::FileDescriptor* file,
     "require 'google/protobuf'\n\n");
 
   for (int i = 0; i < file->dependency_count(); i++) {
-    const std::string& name = file->dependency(i)->name();
-    printer->Print(
-      "require '$name$'\n", "name", StripDotProto(name));
+    if (!MaybeEmitDependency(file->dependency(i), file, printer, error)) {
+      return false;
+    }
   }
 
   printer->Print(
@@ -369,6 +434,7 @@ void GenerateFile(const google::protobuf::FileDescriptor* file,
     GenerateEnumAssignment("", file->enum_type(i), printer);
   }
   EndPackageModules(levels, printer);
+  return true;
 }
 
 bool Generator::Generate(
@@ -384,15 +450,11 @@ bool Generator::Generate(
     return false;
   }
 
-  std::string filename =
-      StripDotProto(file->name()) + ".rb";
   scoped_ptr<io::ZeroCopyOutputStream> output(
-      generator_context->Open(filename));
+      generator_context->Open(GetOutputFilename(file->name())));
   io::Printer printer(output.get(), '$');
 
-  GenerateFile(file, &printer);
-
-  return true;
+  return GenerateFile(file, &printer, error);
 }
 
 }  // namespace ruby
diff --git a/src/google/protobuf/io/coded_stream.h b/src/google/protobuf/io/coded_stream.h
index e3771003..c81a33ac 100644
--- a/src/google/protobuf/io/coded_stream.h
+++ b/src/google/protobuf/io/coded_stream.h
@@ -1136,7 +1136,7 @@ inline void CodedOutputStream::WriteVarint32(uint32 value) {
     // this write won't cross the end, so we can skip the checks.
     uint8* target = buffer_;
     uint8* end = WriteVarint32ToArray(value, target);
-    int size = end - target;
+    int size = static_cast<int>(end - target);
     Advance(size);
   } else {
     WriteVarint32SlowPath(value);
diff --git a/src/google/protobuf/map.h b/src/google/protobuf/map.h
index a182abe6..b5f34042 100644
--- a/src/google/protobuf/map.h
+++ b/src/google/protobuf/map.h
@@ -608,11 +608,17 @@ class Map {
       }
     }
 
-#if __cplusplus >= 201103L && !defined(GOOGLE_PROTOBUF_OS_APPLE) &&     \
-  !defined(GOOGLE_PROTOBUF_OS_NACL) && !defined(GOOGLE_PROTOBUF_OS_ANDROID)
+#if __cplusplus >= 201103L && !defined(GOOGLE_PROTOBUF_OS_APPLE) && \
+    !defined(GOOGLE_PROTOBUF_OS_NACL) &&                            \
+    !defined(GOOGLE_PROTOBUF_OS_ANDROID) &&                         \
+    !defined(GOOGLE_PROTOBUF_OS_EMSCRIPTEN)
     template<class NodeType, class... Args>
     void construct(NodeType* p, Args&&... args) {
-      new (static_cast<void*>(p)) NodeType(std::forward<Args>(args)...);
+      // Clang 3.6 doesn't compile static casting to void* directly. (Issue #1266)
+      // According C++ standard 5.2.9/1: "The static_cast operator shall not cast
+      // away constness". So first the maybe const pointer is casted to const void* and
+      // after the const void* is const casted.
+      new (const_cast<void*>(static_cast<const void*>(p))) NodeType(std::forward<Args>(args)...);
     }
 
     template<class NodeType>
diff --git a/src/google/protobuf/stubs/statusor.h b/src/google/protobuf/stubs/statusor.h
index ad848701..29f869ad 100644
--- a/src/google/protobuf/stubs/statusor.h
+++ b/src/google/protobuf/stubs/statusor.h
@@ -224,7 +224,7 @@ inline StatusOr<T>& StatusOr<T>::operator=(const StatusOr<T>& other) {
 template<typename T>
 template<typename U>
 inline StatusOr<T>::StatusOr(const StatusOr<U>& other)
-    : status_(other.status_), value_(other.status_.ok() ? other.value_ : NULL) {
+    : status_(other.status_), value_(other.status_.ok() ? other.value_ : T()) {
 }
 
 template<typename T>