diff --git a/src/corelib/tools/qrefcount.h b/src/corelib/tools/qrefcount.h
index 17be893744e..9478ff1269f 100644
--- a/src/corelib/tools/qrefcount.h
+++ b/src/corelib/tools/qrefcount.h
@@ -56,17 +56,51 @@ namespace QtPrivate
 class RefCount
 {
 public:
-    inline void ref() {
-        if (atomic.load() > 0)
+    inline bool ref() {
+        int count = atomic.load();
+        if (count == 0) // !isSharable
+            return false;
+        if (count != -1) // !isStatic
             atomic.ref();
+        return true;
     }
 
     inline bool deref() {
-        if (atomic.load() <= 0)
+        int count = atomic.load();
+        if (count == 0) // !isSharable
+            return false;
+        if (count == -1) // isStatic
             return true;
         return atomic.deref();
     }
 
+    bool setSharable(bool sharable)
+    {
+        Q_ASSERT(!isShared());
+        if (sharable)
+            return atomic.testAndSetRelaxed(0, 1);
+        else
+            return atomic.testAndSetRelaxed(1, 0);
+    }
+
+    bool isStatic() const
+    {
+        // Persistent object, never deleted
+        return atomic.load() == -1;
+    }
+
+    bool isSharable() const
+    {
+        // Sharable === Shared ownership.
+        return atomic.load() != 0;
+    }
+
+    bool isShared() const
+    {
+        int count = atomic.load();
+        return (count != 1) && (count != 0);
+    }
+
     inline bool operator==(int value) const
     { return atomic.load() == value; }
     inline bool operator!=(int value) const
diff --git a/tests/auto/corelib/tools/qarraydata/simplevector.h b/tests/auto/corelib/tools/qarraydata/simplevector.h
index 38f61189da3..c5e19f3c556 100644
--- a/tests/auto/corelib/tools/qarraydata/simplevector.h
+++ b/tests/auto/corelib/tools/qarraydata/simplevector.h
@@ -86,6 +86,8 @@ public:
     bool isNull() const { return d.isNull(); }
     bool isEmpty() const { return this->empty(); }
 
+    bool isStatic() const { return d->ref.isStatic(); }
+    bool isShared() const { return d->ref.isShared(); }
     bool isSharedWith(const SimpleVector &other) const { return d == other.d; }
 
     size_t size() const { return d->size; }
diff --git a/tests/auto/corelib/tools/qarraydata/tst_qarraydata.cpp b/tests/auto/corelib/tools/qarraydata/tst_qarraydata.cpp
index 241ef3b3e08..89a1f8bc75d 100644
--- a/tests/auto/corelib/tools/qarraydata/tst_qarraydata.cpp
+++ b/tests/auto/corelib/tools/qarraydata/tst_qarraydata.cpp
@@ -72,13 +72,16 @@ void tst_QArrayData::referenceCounting()
 
         QCOMPARE(int(array.ref), 1);
 
-        array.ref.ref();
+        QVERIFY(!array.ref.isStatic());
+        QVERIFY(array.ref.isSharable());
+
+        QVERIFY(array.ref.ref());
         QCOMPARE(int(array.ref), 2);
 
         QVERIFY(array.ref.deref());
         QCOMPARE(int(array.ref), 1);
 
-        array.ref.ref();
+        QVERIFY(array.ref.ref());
         QCOMPARE(int(array.ref), 2);
 
         QVERIFY(array.ref.deref());
@@ -90,13 +93,35 @@ void tst_QArrayData::referenceCounting()
         // Now would be a good time to free/release allocated data
     }
 
+    {
+        // Reference counting initialized to 0 (non-sharable)
+        QArrayData array = { { Q_BASIC_ATOMIC_INITIALIZER(0) }, 0, 0, 0, 0 };
+
+        QCOMPARE(int(array.ref), 0);
+
+        QVERIFY(!array.ref.isStatic());
+        QVERIFY(!array.ref.isSharable());
+
+        QVERIFY(!array.ref.ref());
+        // Reference counting fails, data should be copied
+        QCOMPARE(int(array.ref), 0);
+
+        QVERIFY(!array.ref.deref());
+        QCOMPARE(int(array.ref), 0);
+
+        // Free/release data
+    }
+
     {
         // Reference counting initialized to -1 (static read-only data)
         QArrayData array = { Q_REFCOUNT_INITIALIZE_STATIC, 0, 0, 0, 0 };
 
         QCOMPARE(int(array.ref), -1);
 
-        array.ref.ref();
+        QVERIFY(array.ref.isStatic());
+        QVERIFY(array.ref.isSharable());
+
+        QVERIFY(array.ref.ref());
         QCOMPARE(int(array.ref), -1);
 
         QVERIFY(array.ref.deref());
@@ -109,11 +134,19 @@ void tst_QArrayData::sharedNullEmpty()
     QArrayData *null = const_cast<QArrayData *>(&QArrayData::shared_null);
     QArrayData *empty = const_cast<QArrayData *>(&QArrayData::shared_empty);
 
+    QVERIFY(null->ref.isStatic());
+    QVERIFY(null->ref.isSharable());
+    QVERIFY(null->ref.isShared());
+
+    QVERIFY(empty->ref.isStatic());
+    QVERIFY(empty->ref.isSharable());
+    QVERIFY(empty->ref.isShared());
+
     QCOMPARE(int(null->ref), -1);
     QCOMPARE(int(empty->ref), -1);
 
-    null->ref.ref();
-    empty->ref.ref();
+    QVERIFY(null->ref.ref());
+    QVERIFY(empty->ref.ref());
 
     QCOMPARE(int(null->ref), -1);
     QCOMPARE(int(empty->ref), -1);
@@ -218,6 +251,26 @@ void tst_QArrayData::simpleVector()
     QVERIFY(v7.capacity() >= size_t(10));
     QVERIFY(v8.capacity() >= size_t(10));
 
+    QVERIFY(v1.isStatic());
+    QVERIFY(v2.isStatic());
+    QVERIFY(v3.isStatic());
+    QVERIFY(v4.isStatic());
+    QVERIFY(v5.isStatic());
+    QVERIFY(v6.isStatic());
+    QVERIFY(!v7.isStatic());
+    QVERIFY(!v8.isStatic());
+
+    QVERIFY(v1.isShared());
+    QVERIFY(v2.isShared());
+    QVERIFY(v3.isShared());
+    QVERIFY(v4.isShared());
+    QVERIFY(v5.isShared());
+    QVERIFY(v6.isShared());
+    QVERIFY(!v7.isShared());
+    QVERIFY((SimpleVector<int>(v7), v7.isShared()));
+    QVERIFY(!v7.isShared());
+    QVERIFY(!v8.isShared());
+
     QVERIFY(v1.isSharedWith(v2));
     QVERIFY(v1.isSharedWith(v3));
     QVERIFY(!v1.isSharedWith(v4));