diff --git a/ortools/util/parse_proto.cc b/ortools/util/parse_proto.cc
index d9a780ec83..3da0bc094f 100644
--- a/ortools/util/parse_proto.cc
+++ b/ortools/util/parse_proto.cc
@@ -37,11 +37,10 @@ class TextFormatErrorCollector : public google::protobuf::io::ErrorCollector {
   ~TextFormatErrorCollector() override = default;
 
   void AddError(int line, int column, const std::string& message) override {
-    collected_errors_.push_back({false, line, column, std::string(message)});
+    collected_errors_.push_back({false, line, column, message});
   }
-  void AddWarning(const int line, const int column,
-                  absl::string_view message) override {
-    collected_errors_.push_back({true, line, column, std::string(message)});
+  void AddWarning(int line, int column, const std::string& message) override {
+    collected_errors_.push_back({true, line, column, message});
   }
 
   // Returns a string listing each collected error.  When an error is associated