diff --git a/buffet/data_encoding.cc b/buffet/data_encoding.cc
index 9f351de..f2de937 100644
--- a/buffet/data_encoding.cc
+++ b/buffet/data_encoding.cc
@@ -77,7 +77,7 @@
                             bool encodeSpaceAsPlus) {
   std::vector<std::string> pairs;
   pairs.reserve(params.size());
-  for (auto&& p : params) {
+  for (const auto& p : params) {
     std::string key = UrlEncode(p.first.c_str(), encodeSpaceAsPlus);
     std::string value = UrlEncode(p.second.c_str(), encodeSpaceAsPlus);
     pairs.push_back(string_utils::Join('=', key, value));
@@ -89,7 +89,7 @@
 WebParamList WebParamsDecode(const std::string& data) {
   WebParamList result;
   std::vector<std::string> params = string_utils::Split(data, '&');
-  for (auto p : params) {
+  for (const auto& p : params) {
     auto pair = string_utils::SplitAtFirst(p, '=');
     result.emplace_back(UrlDecode(pair.first.c_str()),
                         UrlDecode(pair.second.c_str()));