The changes that were made to the QSharedPointer class when Qt was changed to version 4.6 generate warning C4291: "no matching operator delete found; memory will not be freed if initialization throws an exception". The included files provide a simple example of the warning being generated (a text file of the output is also included). My code is required to compile without warnings so this causes substantial problems. The warning appears to be originating from line 261 of the file qsharedpointer_impl.h.