diff --git a/test/screen-uaf-reproducer/main.cpp b/test/screen-uaf-reproducer/main.cpp
index 7a108b2..f45b3de 100644
--- a/test/screen-uaf-reproducer/main.cpp
+++ b/test/screen-uaf-reproducer/main.cpp
@@ -47,7 +47,7 @@ int main(int argc, char *argv[])
     }
 
     std::fprintf(stderr,
-        "screen-uaf-reproducer: %d surfaces created on %d screen(s).\n"
+        "screen-uaf-reproducer: %d surfaces created on %lld screen(s).\n"
         "Toggle an output off/on to trigger the crash.\n",
         kWindows, QGuiApplication::screens().size());