diff --git a/libjsonpb/parse/jsonpb.cpp b/libjsonpb/parse/jsonpb.cpp
index 6c428282b..575155709 100644
--- a/libjsonpb/parse/jsonpb.cpp
+++ b/libjsonpb/parse/jsonpb.cpp
@@ -33,7 +33,7 @@ using google::protobuf::util::TypeResolver;
 static constexpr char kTypeUrlPrefix[] = "type.googleapis.com";
 
 std::string GetTypeUrl(const Message& message) {
-  return std::string(kTypeUrlPrefix) + "/" + message.GetDescriptor()->full_name();
+  return std::string(kTypeUrlPrefix) + "/" + std::string(message.GetDescriptor()->full_name());
 }
 
 ErrorOr<std::string> MessageToJsonString(const Message& message) {