diff --git a/repos/mml/src/app/thread_test/thread_test.cc b/repos/mml/src/app/thread_test/thread_test.cc
index 1848cd9e63..42f2857aa5 100644
--- a/repos/mml/src/app/thread_test/thread_test.cc
+++ b/repos/mml/src/app/thread_test/thread_test.cc
@@ -11,7 +11,7 @@ struct ThreadTest::Main
 {
     Genode::Env &_env;
 
-    Main(env) : _env(env) {}
+    Main(Genode::Env &env) : _env(env) {}
 
     void execute() 
     {