diff --git a/src/google/protobuf/util/message_differencer.cc b/src/google/protobuf/util/message_differencer.cc
index 79c268e..4e2f73a 100644
--- a/src/google/protobuf/util/message_differencer.cc
+++ b/src/google/protobuf/util/message_differencer.cc
@@ -18,6 +18,7 @@
 #include <limits>
 #include <memory>
 #include <utility>
+#include <vector>
 
 #include "google/protobuf/descriptor.pb.h"
 #include "absl/container/flat_hash_map.h"
@@ -653,29 +654,26 @@
     const Message& message, bool base_message) {
   const Descriptor* descriptor = message.GetDescriptor();
 
-  tmp_message_fields_.clear();
-  tmp_message_fields_.reserve(descriptor->field_count() + 1);
+  std::vector<const FieldDescriptor*> message_fields;
+  message_fields.reserve(descriptor->field_count() + 1);
 
   const Reflection* reflection = message.GetReflection();
   if (descriptor->options().map_entry()) {
     if (this->scope_ == PARTIAL && base_message) {
-      reflection->ListFields(message, &tmp_message_fields_);
+      reflection->ListFields(message, &message_fields);
     } else {
       // Map entry fields are always considered present.
       for (int i = 0; i < descriptor->field_count(); i++) {
-        tmp_message_fields_.push_back(descriptor->field(i));
+        message_fields.push_back(descriptor->field(i));
       }
     }
   } else {
-    reflection->ListFields(message, &tmp_message_fields_);
+    reflection->ListFields(message, &message_fields);
   }
   // Add sentinel values to deal with the
   // case where the number of the fields in
   // each list are different.
-  tmp_message_fields_.push_back(nullptr);
-
-  std::vector<const FieldDescriptor*> message_fields(
-      tmp_message_fields_.begin(), tmp_message_fields_.end());
+  message_fields.push_back(nullptr);
 
   return message_fields;
 }
@@ -768,7 +766,8 @@
   size_t index1 = 0;
   size_t index2 = 0;
 
-  tmp_message_fields_.clear();
+  std::vector<const FieldDescriptor*> combined_fields;
+  combined_fields.reserve(1 + std::max(fields1.size(), fields2.size()));
 
   while (index1 < fields1.size() && index2 < fields2.size()) {
     const FieldDescriptor* field1 = fields1[index1];
@@ -776,12 +775,12 @@
 
     if (FieldBefore(field1, field2)) {
       if (fields1_scope == FULL) {
-        tmp_message_fields_.push_back(field1);
+        combined_fields.push_back(field1);
       }
       ++index1;
     } else if (FieldBefore(field2, field1)) {
       if (fields2_scope == FULL) {
-        tmp_message_fields_.push_back(field2);
+        combined_fields.push_back(field2);
       } else if (fields2_scope == PARTIAL &&
                  ShouldCompareNoPresence(message1, *reflection1, field2)) {
         // In order to make MessageDifferencer play nicely with no-presence
@@ -792,20 +791,17 @@
         // value) but will not appear in fields1 (since they have the default
         // value or were never set).
         force_compare_no_presence_fields_.insert(field2);
-        tmp_message_fields_.push_back(field2);
+        combined_fields.push_back(field2);
       }
       ++index2;
     } else {
-      tmp_message_fields_.push_back(field1);
+      combined_fields.push_back(field1);
       ++index1;
       ++index2;
     }
   }
 
-  tmp_message_fields_.push_back(nullptr);
-
-  std::vector<const FieldDescriptor*> combined_fields(
-      tmp_message_fields_.begin(), tmp_message_fields_.end());
+  combined_fields.push_back(nullptr);
 
   return combined_fields;
 }
diff --git a/src/google/protobuf/util/message_differencer.h b/src/google/protobuf/util/message_differencer.h
index 04188e8..5f97878 100644
--- a/src/google/protobuf/util/message_differencer.h
+++ b/src/google/protobuf/util/message_differencer.h
@@ -961,8 +961,6 @@
       map_field_key_comparator_;
   MapEntryKeyComparator map_entry_key_comparator_;
   std::vector<std::unique_ptr<IgnoreCriteria>> ignore_criteria_;
-  // Reused multiple times in RetrieveFields to avoid extra allocations
-  std::vector<const FieldDescriptor*> tmp_message_fields_;
 
   absl::flat_hash_set<const FieldDescriptor*> ignored_fields_;