diff --git a/net/dns/public/scoped_res_state.cc b/net/dns/public/scoped_res_state.cc
index f7dbb5e77..9706d18b0 100644
--- a/net/dns/public/scoped_res_state.cc
+++ b/net/dns/public/scoped_res_state.cc
@@ -4,6 +4,7 @@
 
 #include "net/dns/public/scoped_res_state.h"
 
+#include <cstring>
 #include <memory>
 
 #include "base/check.h"