Bug 62052 – Make the destructors of DataTransferItem and DataTransferItems virtual

• Component: New Bugs
• Status: RESOLVED FIXED

[Nico Weber]

Make the destructors of DataTransferItem and DataTransferItems virtual

[Nico Weber]

Created attachment 95960 [details]
Patch

[Nico Weber]

Yes, this is a real bug in this case:

In file included from third_party/WebKit/Source/WebCore/html/canvas/ArrayBufferView.h:29:
In file included from third_party/WebKit/Source/WebCore/html/canvas/ArrayBuffer.h:30:
third_party/WebKit/Source/JavaScriptCore/wtf/RefCounted.h:141:13:error: delete called on 'WebCore::DataTransferItem' that has virtual functions but non-virtual destructor [-Werror,-Wdelete-non-virtual-dtor]
            delete static_cast<T*>(this);
            ^
third_party/WebKit/Source/JavaScriptCore/wtf/PassRefPtr.h:59:18: note: in instantiation of member function 'WTF::RefCounted<WebCore::DataTransferItem>::deref' requested here
            ptr->deref();
                 ^
third_party/WebKit/Source/JavaScriptCore/wtf/RefPtr.h:58:35: note: in instantiation of function template specialization 'WTF::derefIfNotNull<WebCore::DataTransferItem>' requested here
        ALWAYS_INLINE ~RefPtr() { derefIfNotNull(m_ptr); }
                                  ^
third_party/WebKit/Source/JavaScriptCore/wtf/Vector.h:80:23: note: in instantiation of member function 'WTF::RefPtr<WebCore::DataTransferItem>::~RefPtr' requested here
                cur->~T();
                      ^
third_party/WebKit/Source/JavaScriptCore/wtf/Vector.h:239:69: note: in instantiation of member function 'WTF::VectorDestructor<true, WTF::RefPtr<WebCore::DataTransferItem> >::destruct' requested here
            VectorDestructor<VectorTraits<T>::needsDestruction, T>::destruct(begin, end);
                                                                    ^
third_party/WebKit/Source/JavaScriptCore/wtf/Vector.h:860:25: note: in instantiation of member function 'WTF::VectorTypeOperations<WTF::RefPtr<WebCore::DataTransferItem> >::destruct' requested here
        TypeOperations::destruct(begin() + size, end());
                        ^
third_party/WebKit/Source/JavaScriptCore/wtf/Vector.h:520:25: note: in instantiation of member function 'WTF::Vector<WTF::RefPtr<WebCore::DataTransferItem>, 0>::shrink' requested here
            if (m_size) shrink(0);
                        ^
third_party/WebKit/Source/WebCore/dom/DataTransferItems.h:48:5: note: in instantiation of member function 'WTF::Vector<WTF::RefPtr<WebCore::DataTransferItem>, 0>::~Vector' requested here
    ~DataTransferItems() {}
    ^


The item is added with

    m_items.append(DataTransferItem::create(m_owner, m_context, data, type));

and that returns a polymorphic object, at least with the chromium port (DataTransferItemChromium::create, http://codesearch.google.com/codesearch/p?hl=en#OAMlx_jo-ck/src/third_party/WebKit/Source/WebCore/platform/chromium/DataTransferItemChromium.cpp&q=DataTransferItemChromium::create&exact_package=chromium&l=57 )

[WebKit Commit Bot]

Comment on attachment 95960 [details]
Patch

Clearing flags on attachment: 95960

Committed r88099: <http://trac.webkit.org/changeset/88099>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.