"Peter Dimov" <[EMAIL PROTECTED]> writes: | From: "Gabriel Dos Reis" <[EMAIL PROTECTED]> | > David Abrahams <[EMAIL PROTECTED]> writes: | > | > | Gabriel Dos Reis <[EMAIL PROTECTED]> writes: | > | | > | > Hmm, I have a couple of questions answers to which will help me | > | > get your point. | > | > | > | > 1) Why can't you do that with reinterpret_cast? | > | | > | You can, but the results are non-portable | > | > No more non-portable than with dangerous_cast<>. | | I think that Dave's point is that in | | new(h.storage) Foo; | | there is a char* -> void* implicit conversion as placement new takes a | void*. So the placement new performs char* -> void* -> Foo* (by constructing | a Foo at (void*)h.storage), which - in theory - might not be the same as | char* -> Foo*.
But then, that theoretical implementation can remember the type from which the conversion to void* was made and may issue an error when an attempt is made to dereference the pointer obtained by recasting the result of static_cast<void*>(h.storage) to Foo*. Practical notes: Historically, char* was used as the type of "raw memory" until "void*" was invented. And since then char* and void* continues to have the same properties as raw-memory issues are concerned. -- Gaby _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
