diff --git a/src/test/run-make/thumb-none-qemu/script.sh b/src/test/run-make/thumb-none-qemu/script.sh
index 5c46c4bd26dc..c7133f8fb7fc 100644
--- a/src/test/run-make/thumb-none-qemu/script.sh
+++ b/src/test/run-make/thumb-none-qemu/script.sh
@@ -8,6 +8,7 @@ pushd $WORK_DIR
     rm -rf $CRATE || echo OK
     cp -a $HERE/example .
     pushd $CRATE
-        $CARGO run --target $TARGET
+        $CARGO run --target $TARGET           | grep "x = 42"
+        $CARGO run --target $TARGET --release | grep "x = 42"
     popd
 popd