diff --git a/test_mx_util.c b/test_mx_util.c
index 05389f42..4d4c4f38 100644
--- a/test_mx_util.c
+++ b/test_mx_util.c
@@ -367,7 +367,7 @@ static void test_mx_strvec_cachebug() {
     strvec2 = mx_strvec_new();
     assert(mx_strvec_length(strvec2) == 0);
     if (strvec != strvec2)
-        fprintf(stderr, "Warning: Can't test strvec cache bug. Skipping.");
+        fprintf(stderr, "Warning: Can't test strvec cache bug. Skipping.\n");
     mx_free_null(strvec2);
     mx_free_null(str);
 }