diff --git a/src/test/ui/macros/assert-format-lazy.rs b/src/test/ui/macros/assert-format-lazy.rs
index e0e2bd5a970e..c7f05d763b7a 100644
--- a/src/test/ui/macros/assert-format-lazy.rs
+++ b/src/test/ui/macros/assert-format-lazy.rs
@@ -1,4 +1,5 @@
 // run-pass
+// compile-flags: -C debug_assertions=yes
 
 #[allow(unreachable_code)]
 fn main() {