5 files changed, 6 insertions, 6 deletions
diff --git a/src/corelib/tools/qhash.h b/src/corelib/tools/qhash.h
index 25cece4673..cc120aa09e 100644
--- a/src/corelib/tools/qhash.h
+++ b/src/corelib/tools/qhash.h
@@ -291,7 +291,7 @@ public:
 
     inline void detach() { if (d->ref != 1) detach_helper(); }
     inline bool isDetached() const { return d->ref == 1; }
-    inline void setSharable(bool sharable) { if (!sharable) detach(); d->sharable = sharable; }
+    inline void setSharable(bool sharable) { if (!sharable) detach(); if (d != &QHashData::shared_null) d->sharable = sharable; }
     inline bool isSharedWith(const QHash<Key, T> &other) const { return d == other.d; }
 
     void clear();
diff --git a/src/corelib/tools/qlinkedlist.h b/src/corelib/tools/qlinkedlist.h
index bcad210d30..36cbc68eb8 100644
--- a/src/corelib/tools/qlinkedlist.h
+++ b/src/corelib/tools/qlinkedlist.h
@@ -97,7 +97,7 @@ public:
     inline void detach()
     { if (d->ref != 1) detach_helper(); }
     inline bool isDetached() const { return d->ref == 1; }
-    inline void setSharable(bool sharable) { if (!sharable) detach(); d->sharable = sharable; }
+    inline void setSharable(bool sharable) { if (!sharable) detach(); if (d != &QLinkedListData::shared_null) d->sharable = sharable; }
     inline bool isSharedWith(const QLinkedList<T> &other) const { return d == other.d; }
 
     inline bool isEmpty() const { return d->size == 0; }
diff --git a/src/corelib/tools/qlist.h b/src/corelib/tools/qlist.h
index e9e44dbb10..5c8a58a196 100644
--- a/src/corelib/tools/qlist.h
+++ b/src/corelib/tools/qlist.h
@@ -143,7 +143,7 @@ public:
     }
 
     inline bool isDetached() const { return d->ref == 1; }
-    inline void setSharable(bool sharable) { if (!sharable) detach(); d->sharable = sharable; }
+    inline void setSharable(bool sharable) { if (!sharable) detach(); if (d != &QListData::shared_null) d->sharable = sharable; }
     inline bool isSharedWith(const QList<T> &other) const { return d == other.d; }
 
     inline bool isEmpty() const { return p.isEmpty(); }
diff --git a/src/corelib/tools/qmap.h b/src/corelib/tools/qmap.h
index ff181d5071..8beae03a6e 100644
--- a/src/corelib/tools/qmap.h
+++ b/src/corelib/tools/qmap.h
@@ -204,9 +204,9 @@ public:
 
     inline void detach() { if (d->ref != 1) detach_helper(); }
     inline bool isDetached() const { return d->ref == 1; }
-    inline void setSharable(bool sharable) { if (!sharable) detach(); d->sharable = sharable; }
+    inline void setSharable(bool sharable) { if (!sharable) detach(); if (d != &QMapData::shared_null) d->sharable = sharable; }
     inline bool isSharedWith(const QMap<Key, T> &other) const { return d == other.d; }
-    inline void setInsertInOrder(bool ordered) { d->insertInOrder = ordered; }
+    inline void setInsertInOrder(bool ordered) { if (ordered) detach(); if (d != &QMapData::shared_null) d->insertInOrder = ordered; }
 
     void clear();
 
diff --git a/src/corelib/tools/qvector.h b/src/corelib/tools/qvector.h
index 34d1ed3717..eab9311eb3 100644
--- a/src/corelib/tools/qvector.h
+++ b/src/corelib/tools/qvector.h
@@ -146,7 +146,7 @@ public:
 
     inline void detach() { if (d->ref != 1) detach_helper(); }
     inline bool isDetached() const { return d->ref == 1; }
-    inline void setSharable(bool sharable) { if (!sharable) detach(); d->sharable = sharable; }
+    inline void setSharable(bool sharable) { if (!sharable) detach(); if (d != &QVectorData::shared_null) d->sharable = sharable; }
     inline bool isSharedWith(const QVector<T> &other) const { return d == other.d; }
 
     inline T *data() { detach(); return p->array; }