diff --git a/src/corelib/time/qdatetime.cpp b/src/corelib/time/qdatetime.cpp
index a61a7d5706..faf3fe38de 100644
--- a/src/corelib/time/qdatetime.cpp
+++ b/src/corelib/time/qdatetime.cpp
@@ -3050,7 +3050,9 @@ static void setDateTime(QDateTimeData &d, QDate date, QTime time)
     if (mul_overflow(days, std::integral_constant<qint64, MSECS_PER_DAY>(), &msecs)
         || add_overflow(msecs, qint64(ds), &msecs)) {
         newStatus = QDateTimePrivate::StatusFlags{};
-    } else if (d.isShort()) {
+        msecs = 0;
+    }
+    if (d.isShort()) {
         // let's see if we can keep this short
         if (msecsCanBeSmall(msecs)) {
             // yes, we can
diff --git a/tests/auto/corelib/time/qdatetime/tst_qdatetime.cpp b/tests/auto/corelib/time/qdatetime/tst_qdatetime.cpp
index 166ce260a5..ce0e899a25 100644
--- a/tests/auto/corelib/time/qdatetime/tst_qdatetime.cpp
+++ b/tests/auto/corelib/time/qdatetime/tst_qdatetime.cpp
@@ -717,6 +717,13 @@ void tst_QDateTime::setMSecsSinceEpoch()
 
     QDateTime reference(QDate(1970, 1, 1), QTime(0, 0), Qt::UTC);
     QCOMPARE(dt, reference.addMSecs(msecs));
+
+    if ((localTimeType == LocalTimeAheadOfUtc && msecs == std::numeric_limits<qint64>::max())
+        || (localTimeType == LocalTimeBehindUtc && msecs == std::numeric_limits<qint64>::min())) {
+        QDateTime curt = QDate(1970, 1, 1).startOfDay(); // initially in short-form
+        curt.setMSecsSinceEpoch(msecs); // Overflows due to offset
+        QVERIFY(!curt.isValid());
+    }
 }
 
 void tst_QDateTime::fromMSecsSinceEpoch_data()