diff --git a/src/google/protobuf/any.pb.cc b/src/google/protobuf/any.pb.cc
index 4058400779..91d947581c 100644
--- a/src/google/protobuf/any.pb.cc
+++ b/src/google/protobuf/any.pb.cc
@@ -288,10 +288,10 @@ PROTOBUF_NOINLINE void Any::Clear() {
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000003u) {
     if (cached_has_bits & 0x00000001u) {
-      _impl_.type_url_.ClearToEmpty();
+      _impl_.type_url_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000002u) {
-      _impl_.value_.ClearToEmpty();
+      _impl_.value_.ClearNonDefaultToEmpty();
     }
   }
   _impl_._has_bits_.Clear();
@@ -389,11 +389,19 @@ void Any::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::google::pro
     if (cached_has_bits & 0x00000001u) {
       if (!from._internal_type_url().empty()) {
         _this->_internal_set_type_url(from._internal_type_url());
+      } else {
+        if (_this->_impl_.type_url_.IsDefault()) {
+          _this->_internal_set_type_url("");
+        }
       }
     }
     if (cached_has_bits & 0x00000002u) {
       if (!from._internal_value().empty()) {
         _this->_internal_set_value(from._internal_value());
+      } else {
+        if (_this->_impl_.value_.IsDefault()) {
+          _this->_internal_set_value("");
+        }
       }
     }
   }
diff --git a/src/google/protobuf/api.pb.cc b/src/google/protobuf/api.pb.cc
index 45f2f1cfdd..2d0ab9ec2b 100644
--- a/src/google/protobuf/api.pb.cc
+++ b/src/google/protobuf/api.pb.cc
@@ -497,10 +497,10 @@ PROTOBUF_NOINLINE void Api::Clear() {
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000007u) {
     if (cached_has_bits & 0x00000001u) {
-      _impl_.name_.ClearToEmpty();
+      _impl_.name_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000002u) {
-      _impl_.version_.ClearToEmpty();
+      _impl_.version_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000004u) {
       ABSL_DCHECK(_impl_.source_context_ != nullptr);
@@ -697,11 +697,19 @@ void Api::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::google::pro
     if (cached_has_bits & 0x00000001u) {
       if (!from._internal_name().empty()) {
         _this->_internal_set_name(from._internal_name());
+      } else {
+        if (_this->_impl_.name_.IsDefault()) {
+          _this->_internal_set_name("");
+        }
       }
     }
     if (cached_has_bits & 0x00000002u) {
       if (!from._internal_version().empty()) {
         _this->_internal_set_version(from._internal_version());
+      } else {
+        if (_this->_impl_.version_.IsDefault()) {
+          _this->_internal_set_version("");
+        }
       }
     }
     if (cached_has_bits & 0x00000004u) {
@@ -981,13 +989,13 @@ PROTOBUF_NOINLINE void Method::Clear() {
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000007u) {
     if (cached_has_bits & 0x00000001u) {
-      _impl_.name_.ClearToEmpty();
+      _impl_.name_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000002u) {
-      _impl_.request_type_url_.ClearToEmpty();
+      _impl_.request_type_url_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000004u) {
-      _impl_.response_type_url_.ClearToEmpty();
+      _impl_.response_type_url_.ClearNonDefaultToEmpty();
     }
   }
   if (cached_has_bits & 0x00000038u) {
@@ -1177,16 +1185,28 @@ void Method::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::google::
     if (cached_has_bits & 0x00000001u) {
       if (!from._internal_name().empty()) {
         _this->_internal_set_name(from._internal_name());
+      } else {
+        if (_this->_impl_.name_.IsDefault()) {
+          _this->_internal_set_name("");
+        }
       }
     }
     if (cached_has_bits & 0x00000002u) {
       if (!from._internal_request_type_url().empty()) {
         _this->_internal_set_request_type_url(from._internal_request_type_url());
+      } else {
+        if (_this->_impl_.request_type_url_.IsDefault()) {
+          _this->_internal_set_request_type_url("");
+        }
       }
     }
     if (cached_has_bits & 0x00000004u) {
       if (!from._internal_response_type_url().empty()) {
         _this->_internal_set_response_type_url(from._internal_response_type_url());
+      } else {
+        if (_this->_impl_.response_type_url_.IsDefault()) {
+          _this->_internal_set_response_type_url("");
+        }
       }
     }
     if (cached_has_bits & 0x00000008u) {
@@ -1399,10 +1419,10 @@ PROTOBUF_NOINLINE void Mixin::Clear() {
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000003u) {
     if (cached_has_bits & 0x00000001u) {
-      _impl_.name_.ClearToEmpty();
+      _impl_.name_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000002u) {
-      _impl_.root_.ClearToEmpty();
+      _impl_.root_.ClearNonDefaultToEmpty();
     }
   }
   _impl_._has_bits_.Clear();
@@ -1502,11 +1522,19 @@ void Mixin::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::google::p
     if (cached_has_bits & 0x00000001u) {
       if (!from._internal_name().empty()) {
         _this->_internal_set_name(from._internal_name());
+      } else {
+        if (_this->_impl_.name_.IsDefault()) {
+          _this->_internal_set_name("");
+        }
       }
     }
     if (cached_has_bits & 0x00000002u) {
       if (!from._internal_root().empty()) {
         _this->_internal_set_root(from._internal_root());
+      } else {
+        if (_this->_impl_.root_.IsDefault()) {
+          _this->_internal_set_root("");
+        }
       }
     }
   }
diff --git a/src/google/protobuf/source_context.pb.cc b/src/google/protobuf/source_context.pb.cc
index 4fe1961a37..7ea33899cb 100644
--- a/src/google/protobuf/source_context.pb.cc
+++ b/src/google/protobuf/source_context.pb.cc
@@ -259,7 +259,7 @@ PROTOBUF_NOINLINE void SourceContext::Clear() {
 
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000001u) {
-    _impl_.file_name_.ClearToEmpty();
+    _impl_.file_name_.ClearNonDefaultToEmpty();
   }
   _impl_._has_bits_.Clear();
   _internal_metadata_.Clear<::google::protobuf::UnknownFieldSet>();
@@ -339,6 +339,10 @@ void SourceContext::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::g
   if (cached_has_bits & 0x00000001u) {
     if (!from._internal_file_name().empty()) {
       _this->_internal_set_file_name(from._internal_file_name());
+    } else {
+      if (_this->_impl_.file_name_.IsDefault()) {
+        _this->_internal_set_file_name("");
+      }
     }
   }
   _this->_impl_._has_bits_[0] |= cached_has_bits;
diff --git a/src/google/protobuf/type.pb.cc b/src/google/protobuf/type.pb.cc
index cd1c7c1993..56314d9905 100644
--- a/src/google/protobuf/type.pb.cc
+++ b/src/google/protobuf/type.pb.cc
@@ -652,10 +652,10 @@ PROTOBUF_NOINLINE void Type::Clear() {
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000007u) {
     if (cached_has_bits & 0x00000001u) {
-      _impl_.name_.ClearToEmpty();
+      _impl_.name_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000002u) {
-      _impl_.edition_.ClearToEmpty();
+      _impl_.edition_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000004u) {
       ABSL_DCHECK(_impl_.source_context_ != nullptr);
@@ -850,11 +850,19 @@ void Type::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::google::pr
     if (cached_has_bits & 0x00000001u) {
       if (!from._internal_name().empty()) {
         _this->_internal_set_name(from._internal_name());
+      } else {
+        if (_this->_impl_.name_.IsDefault()) {
+          _this->_internal_set_name("");
+        }
       }
     }
     if (cached_has_bits & 0x00000002u) {
       if (!from._internal_edition().empty()) {
         _this->_internal_set_edition(from._internal_edition());
+      } else {
+        if (_this->_impl_.edition_.IsDefault()) {
+          _this->_internal_set_edition("");
+        }
       }
     }
     if (cached_has_bits & 0x00000004u) {
@@ -1157,16 +1165,16 @@ PROTOBUF_NOINLINE void Field::Clear() {
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x0000000fu) {
     if (cached_has_bits & 0x00000001u) {
-      _impl_.name_.ClearToEmpty();
+      _impl_.name_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000002u) {
-      _impl_.type_url_.ClearToEmpty();
+      _impl_.type_url_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000004u) {
-      _impl_.json_name_.ClearToEmpty();
+      _impl_.json_name_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000008u) {
-      _impl_.default_value_.ClearToEmpty();
+      _impl_.default_value_.ClearNonDefaultToEmpty();
     }
   }
   if (cached_has_bits & 0x000000f0u) {
@@ -1409,21 +1417,37 @@ void Field::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::google::p
     if (cached_has_bits & 0x00000001u) {
       if (!from._internal_name().empty()) {
         _this->_internal_set_name(from._internal_name());
+      } else {
+        if (_this->_impl_.name_.IsDefault()) {
+          _this->_internal_set_name("");
+        }
       }
     }
     if (cached_has_bits & 0x00000002u) {
       if (!from._internal_type_url().empty()) {
         _this->_internal_set_type_url(from._internal_type_url());
+      } else {
+        if (_this->_impl_.type_url_.IsDefault()) {
+          _this->_internal_set_type_url("");
+        }
       }
     }
     if (cached_has_bits & 0x00000004u) {
       if (!from._internal_json_name().empty()) {
         _this->_internal_set_json_name(from._internal_json_name());
+      } else {
+        if (_this->_impl_.json_name_.IsDefault()) {
+          _this->_internal_set_json_name("");
+        }
       }
     }
     if (cached_has_bits & 0x00000008u) {
       if (!from._internal_default_value().empty()) {
         _this->_internal_set_default_value(from._internal_default_value());
+      } else {
+        if (_this->_impl_.default_value_.IsDefault()) {
+          _this->_internal_set_default_value("");
+        }
       }
     }
     if (cached_has_bits & 0x00000010u) {
@@ -1714,10 +1738,10 @@ PROTOBUF_NOINLINE void Enum::Clear() {
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000007u) {
     if (cached_has_bits & 0x00000001u) {
-      _impl_.name_.ClearToEmpty();
+      _impl_.name_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000002u) {
-      _impl_.edition_.ClearToEmpty();
+      _impl_.edition_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000004u) {
       ABSL_DCHECK(_impl_.source_context_ != nullptr);
@@ -1894,11 +1918,19 @@ void Enum::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::google::pr
     if (cached_has_bits & 0x00000001u) {
       if (!from._internal_name().empty()) {
         _this->_internal_set_name(from._internal_name());
+      } else {
+        if (_this->_impl_.name_.IsDefault()) {
+          _this->_internal_set_name("");
+        }
       }
     }
     if (cached_has_bits & 0x00000002u) {
       if (!from._internal_edition().empty()) {
         _this->_internal_set_edition(from._internal_edition());
+      } else {
+        if (_this->_impl_.edition_.IsDefault()) {
+          _this->_internal_set_edition("");
+        }
       }
     }
     if (cached_has_bits & 0x00000004u) {
@@ -2129,7 +2161,7 @@ PROTOBUF_NOINLINE void EnumValue::Clear() {
   _impl_.options_.Clear();
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000001u) {
-    _impl_.name_.ClearToEmpty();
+    _impl_.name_.ClearNonDefaultToEmpty();
   }
   _impl_.number_ = 0;
   _impl_._has_bits_.Clear();
@@ -2250,6 +2282,10 @@ void EnumValue::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::googl
     if (cached_has_bits & 0x00000001u) {
       if (!from._internal_name().empty()) {
         _this->_internal_set_name(from._internal_name());
+      } else {
+        if (_this->_impl_.name_.IsDefault()) {
+          _this->_internal_set_name("");
+        }
       }
     }
     if (cached_has_bits & 0x00000002u) {
@@ -2452,7 +2488,7 @@ PROTOBUF_NOINLINE void Option::Clear() {
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000003u) {
     if (cached_has_bits & 0x00000001u) {
-      _impl_.name_.ClearToEmpty();
+      _impl_.name_.ClearNonDefaultToEmpty();
     }
     if (cached_has_bits & 0x00000002u) {
       ABSL_DCHECK(_impl_.value_ != nullptr);
@@ -2553,6 +2589,10 @@ void Option::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::google::
     if (cached_has_bits & 0x00000001u) {
       if (!from._internal_name().empty()) {
         _this->_internal_set_name(from._internal_name());
+      } else {
+        if (_this->_impl_.name_.IsDefault()) {
+          _this->_internal_set_name("");
+        }
       }
     }
     if (cached_has_bits & 0x00000002u) {
diff --git a/src/google/protobuf/wrappers.pb.cc b/src/google/protobuf/wrappers.pb.cc
index d17791a6f2..1861510a20 100644
--- a/src/google/protobuf/wrappers.pb.cc
+++ b/src/google/protobuf/wrappers.pb.cc
@@ -2198,7 +2198,7 @@ PROTOBUF_NOINLINE void StringValue::Clear() {
 
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000001u) {
-    _impl_.value_.ClearToEmpty();
+    _impl_.value_.ClearNonDefaultToEmpty();
   }
   _impl_._has_bits_.Clear();
   _internal_metadata_.Clear<::google::protobuf::UnknownFieldSet>();
@@ -2278,6 +2278,10 @@ void StringValue::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::goo
   if (cached_has_bits & 0x00000001u) {
     if (!from._internal_value().empty()) {
       _this->_internal_set_value(from._internal_value());
+    } else {
+      if (_this->_impl_.value_.IsDefault()) {
+        _this->_internal_set_value("");
+      }
     }
   }
   _this->_impl_._has_bits_[0] |= cached_has_bits;
@@ -2451,7 +2455,7 @@ PROTOBUF_NOINLINE void BytesValue::Clear() {
 
   cached_has_bits = _impl_._has_bits_[0];
   if (cached_has_bits & 0x00000001u) {
-    _impl_.value_.ClearToEmpty();
+    _impl_.value_.ClearNonDefaultToEmpty();
   }
   _impl_._has_bits_.Clear();
   _internal_metadata_.Clear<::google::protobuf::UnknownFieldSet>();
@@ -2529,6 +2533,10 @@ void BytesValue::MergeImpl(::google::protobuf::MessageLite& to_msg, const ::goog
   if (cached_has_bits & 0x00000001u) {
     if (!from._internal_value().empty()) {
       _this->_internal_set_value(from._internal_value());
+    } else {
+      if (_this->_impl_.value_.IsDefault()) {
+        _this->_internal_set_value("");
+      }
     }
   }
   _this->_impl_._has_bits_[0] |= cached_has_bits;