El 20/06/2012 19:54, Tr3wory escribió:
But rv<TYPE> is derived from TYPE so to me it looks like the two type is compatible, therefore the code didn't violate the strict aliasing rules, so the attribute is not necessary. (BTW can we violate the strict aliasing rules trough static_cast if we don't do any chained conversion trough void*?)
It might not break strict aliasing (I'm not an expert) but it is undefined behavior to static_cast down a hierarchy to a type that isn't actually the type of the object. Boost.Move uses this undefined behavior hole and the GCC behavior is fixed with may_alias. I haven't found a better solution.
On the other hand, if it's really breaks the rules then we solved the problem for gcc, but we still have undefined behavior on every other compiler.
It's undefined behavior in GCC also.
Can we fix this somehow?
I haven't found a better alternative. Ion