diff --git a/src/prediction/user_history_predictor.cc b/src/prediction/user_history_predictor.cc
index b68dbbfb8..24da4dd2a 100644
--- a/src/prediction/user_history_predictor.cc
+++ b/src/prediction/user_history_predictor.cc
@@ -841,7 +841,7 @@ bool UserHistoryPredictor::RomanFuzzyPrefixMatch(
       // swap.
       if (i + 1 < prefix.size()) {
         string swapped_prefix = prefix;
-        swap(swapped_prefix[i], swapped_prefix[i + 1]);
+        std::swap(swapped_prefix[i], swapped_prefix[i + 1]);
         if (Util::StartsWith(str, swapped_prefix)) {
           return true;
         }