http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54293
--- Comment #9 from Daniel Krügler <daniel.kruegler at googlemail dot com> 2012-08-21 06:13:50 UTC --- (In reply to comment #8) > > I agree with your analysis, but would like to point out that there is change > > planned to essentially this part of the wording due to > > > > http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#616 > > > > Assuming it becomes accepted E1.E2 will become an xvalue in this case (SE > > bullet 2 of the P/R) > > Thanks for the info, it is interesting (although I can't see the relevance of > this particular change to the issues it should solve, which are basically > about > using uninitialized objects). Well, this addition *would* change the expected outcome. Because given the CWG 616 P/R the expression ValueHolder<int>().v becomes an xvalue (The special rule about class rvalues is no longer relevant here), this means that the compiler shall *not* copy-initialize a temporary as described in the very last bullet of 8.5.3/5. In other words: In this case IsValid(&ref_int) will hold for the same reasons as it holds for IsValid(&ref_obj).
