third_party/protobuf: Update to HEAD (83d681ee2c)

third_party/protobuf/src/google/protobuf/generated_message_util.cc

Index: third_party/protobuf/src/google/protobuf/generated_message_util.cc
diff --git a/third_party/protobuf/src/google/protobuf/generated_message_util.cc b/third_party/protobuf/src/google/protobuf/generated_message_util.cc
index 334051a013e4098afea6eed399a54caae30ac729..c4c8eefce259d74ba676bf777364d33cdd96eb20 100644
--- a/third_party/protobuf/src/google/protobuf/generated_message_util.cc
+++ b/third_party/protobuf/src/google/protobuf/generated_message_util.cc
@@ -48,24 +48,27 @@ double NaN() {
   return std::numeric_limits<double>::quiet_NaN();
 }
 
-const ::std::string* empty_string_;
+ExplicitlyConstructed< ::std::string> fixed_address_empty_string;
 GOOGLE_PROTOBUF_DECLARE_ONCE(empty_string_once_init_);
 
 void DeleteEmptyString() {
-  delete empty_string_;
+  GetEmptyStringAlreadyInited().~string();
 }
 
 void InitEmptyString() {
-  empty_string_ = new string;
+  fixed_address_empty_string.DefaultConstruct();
   OnShutdown(&DeleteEmptyString);
 }
 
+const ::std::string& GetEmptyStringAlreadyInited() {
+  return fixed_address_empty_string.get();
+}
+
 const ::std::string& GetEmptyString() {
   ::google::protobuf::GoogleOnceInit(&empty_string_once_init_, &InitEmptyString);
   return GetEmptyStringAlreadyInited();
 }
 
-
 int StringSpaceUsedExcludingSelf(const string& str) {
   const void* start = &str;
   const void* end = &str + 1;
@@ -79,6 +82,12 @@ int StringSpaceUsedExcludingSelf(const string& str) {
 
 
 
+void MergeFromFail(const char* file, int line) {
+  GOOGLE_CHECK(false) << file << ":" << line;
+  // Open-source GOOGLE_CHECK(false) is not NORETURN.
+  exit(1);
+}
+
 }  // namespace internal
 }  // namespace protobuf
 }  // namespace google