diff --git a/src/corelib/tools/qset.h b/src/corelib/tools/qset.h
index d403a0416e..deccaaf387 100644
--- a/src/corelib/tools/qset.h
+++ b/src/corelib/tools/qset.h
@@ -229,13 +229,10 @@ Q_INLINE_TEMPLATE void QSet<T>::reserve(qsizetype asize) { q_hash.reserve(asize)
 template <class T>
 Q_INLINE_TEMPLATE QSet<T> &QSet<T>::unite(const QSet<T> &other)
 {
-    if (q_hash.isSharedWith(other.q_hash))
-        return *this;
-    QSet<T> tmp = other;
-    if (size() < other.size())
-        swap(tmp);
-    for (const auto &e : std::as_const(tmp))
-        insert(e);
+    if (!q_hash.isSharedWith(other.q_hash)) {
+        for (const T &e : other)
+            insert(e);
+    }
     return *this;
 }
 
diff --git a/tests/auto/corelib/tools/qset/tst_qset.cpp b/tests/auto/corelib/tools/qset/tst_qset.cpp
index 2bb300a0c5..34e9334296 100644
--- a/tests/auto/corelib/tools/qset/tst_qset.cpp
+++ b/tests/auto/corelib/tools/qset/tst_qset.cpp
@@ -898,7 +898,7 @@ void tst_QSet::setOperationsOnEmptySet()
 
         empty.unite(nonEmpty);
         QCOMPARE(empty, nonEmpty);
-        QVERIFY(!empty.isDetached());
+        QVERIFY(empty.isDetached());
     }
 }
 
@@ -1312,11 +1312,9 @@ void tst_QSet::setOperationsPickEquivalentElementsFromLHSContainer_impl()
         //       (unlike other Qt containers, QSet's insertion behavior is STL-compliant):
         //
         QVERIFY(lhsCopy.contains(OneL));
-        QEXPECT_FAIL("", "QTBUG-132500", Continue);
         QCOMPARE(lhsCopy.find(OneL)->id, OneL.id);
 
         QVERIFY(lhsCopy.contains(TwoL));
-        QEXPECT_FAIL("", "QTBUG-132500", Continue);
         QCOMPARE(lhsCopy.find(TwoL)->id, TwoL.id);
 
         QVERIFY(lhsCopy.contains(ThreeL));