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<p class=MsoNormal>Hi,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>We have been doing some research inside of Autodesk on one
aspect of the current FdoPtr implementation. The definition of this smart pointer
contains a NULL check that throws an Fdo exception if a NULL pointer is accessed.
This is a behavior unlike any other smart pointer implementation we are aware
of at this point. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>While this check does provide some help in keeping programs based
on FDO more stable it has a variety of problems associated with it. Most prominently
it increases DLL sizes quite a bit due to in-lining of the FdoPtr method and
has a small negative performance impact on our applications. Also, the way it
is used today this code can potentially create memory corruption as the
exception could be thrown by the FDO dll while the destruction of the exception
happens in the application code. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>With that I would like to propose that we remove this NULL
check and recommend that applications implement the operating system exception
handler for accessing invalid memory. This would then handle all NULL pointer
accesses and not just FDO null pointer access.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>What do you all think about this?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Cheers,<o:p></o:p></p>
<p class=MsoNormal> Carsten<o:p></o:p></p>
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