diff --git a/tests/include/mir/test/barrier.h b/tests/include/mir/test/barrier.h
index 2d349c78bf1..e1f8f7d118c 100644
--- a/tests/include/mir/test/barrier.h
+++ b/tests/include/mir/test/barrier.h
@@ -38,7 +38,7 @@ class Barrier
     void ready()
     {
         std::unique_lock lock(mutex);
-        if (--wait_threads)
+        if ((--wait_threads) > 0)
         {
             if (!cv.wait_for(lock, std::chrono::minutes(1), [&]{ return wait_threads == 0; }))
                 throw std::runtime_error("Timeout");