diff --git a/tests/auto/corelib/thread/qfuturesynchronizer/tst_qfuturesynchronizer.cpp b/tests/auto/corelib/thread/qfuturesynchronizer/tst_qfuturesynchronizer.cpp
index b2efd6473b6..e198bb931e2 100644
--- a/tests/auto/corelib/thread/qfuturesynchronizer/tst_qfuturesynchronizer.cpp
+++ b/tests/auto/corelib/thread/qfuturesynchronizer/tst_qfuturesynchronizer.cpp
@@ -45,6 +45,11 @@ void tst_QFutureSynchronizer::setFutureAliasingExistingMember()
     // WHEN: calling setFuture() with an alias of the QFuture already in `synchronizer`:
     //
     for (int i = 0; i < 2; ++i) {
+        // The next line triggers -Wdangling-reference, but it's a FP because
+        // of implicit sharing. We cannot keep a copy of synchronizer.futures()
+        // around to avoid the warning, as the extra copy would cause a detach()
+        // of m_futures inside setFuture() with the consequence that `f` no longer
+        // aliases an element in m_futures, which is the goal of this test.
         const auto &f = synchronizer.futures().constFirst();
         synchronizer.setFuture(f);
     }