diff --git a/reftable/stack_test.c b/reftable/stack_test.c
index eb0b7228b0..d628420e63 100644
--- a/reftable/stack_test.c
+++ b/reftable/stack_test.c
@@ -814,6 +814,7 @@ static void test_reftable_stack_auto_compaction(void)
 		EXPECT_ERR(err);
 
 		err = reftable_stack_auto_compact(st);
+		EXPECT_ERR(err);
 		EXPECT(i < 3 || st->merged->stack_len < 2 * fastlog2(i));
 	}