On 04/29/2011 04:08 PM, Basile Starynkevitch wrote: [...]
which is also what I expect. I have no idea if it is conforming to standards. But I notice that the test about this is remaining in the code. So apparently GCC 4.6 does not make the hypothesis that this is never null, otherwise it would have optimized the test by removing it. What I don't know (and I am asking) is if such an hypothetical optimization is conforming to standards. My biased feeling is that it is not (because I found no explicit& unambiguous mention in standard legal text that this is never null).
9.3.1 seems pretty clear:
If a non-static member function of a class X is called for an object that is not of type X, or of a type derived from X, the behavior is undefined.
A null pointer does not point to an object of type X, so the optimization would be conforming.
Jason
