diff --git a/src/corelib/tools/qhash.cpp b/src/corelib/tools/qhash.cpp
index 933dff84ab5..092985887f6 100644
--- a/src/corelib/tools/qhash.cpp
+++ b/src/corelib/tools/qhash.cpp
@@ -740,6 +740,7 @@ static uint qt_create_qhash_seed()
 /*
     The QHash seed itself.
 */
+// ### Qt 7: this should use size_t, not int.
 static QBasicAtomicInt qt_qhash_seed = Q_BASIC_ATOMIC_INITIALIZER(-1);
 
 /*!
diff --git a/src/corelib/tools/qhashfunctions.h b/src/corelib/tools/qhashfunctions.h
index 25f9c1f1e45..018c317834b 100644
--- a/src/corelib/tools/qhashfunctions.h
+++ b/src/corelib/tools/qhashfunctions.h
@@ -64,6 +64,7 @@ class QByteArray;
 class QString;
 class QLatin1String;
 
+// ### Qt 7: these should use size_t, not int.
 Q_CORE_EXPORT int qGlobalQHashSeed();
 Q_CORE_EXPORT void qSetGlobalQHashSeed(int newSeed);