diff --git a/components/script/lib.rs b/components/script/lib.rs
index 3f1cac6bf25..2cf8f99d4f3 100644
--- a/components/script/lib.rs
+++ b/components/script/lib.rs
@@ -227,5 +227,5 @@ mod timers;
 pub mod textinput;
 mod devtools;
 
-#[cfg(test)]
+#[cfg(all(test, target_word_size = "64"))]
 mod tests;