diff --git a/src/test.cc b/src/test.cc
index 41fd4ca..613eb83 100644
--- a/src/test.cc
+++ b/src/test.cc
@@ -1,6 +1,8 @@
 
 #include <cstddef>
 
+namespace {
+
 namespace std {
 struct string {
   string(char const* str) {}
@@ -145,3 +147,5 @@ int main2() {
   test2();
   return 0;
 }
+
+}