libstdc++/10783: std::vector::reverse_iterator could be smaller

[Paolo Carlini]

Well, on second thought, and giving justice to the clear
explanation in V&J, in their §16.2.2 it is clearly stated
that the EBCO has no equivalent for data members: this is
reasonable considering that it would create problems with
the representation of pointers to members.

Therefore reverse_iterator is expected to have the same
size of its iterator empty base (thanks to EBCO) + the size
of its member current, that is two times the size of a
plain iterator.

Do you agree?

Paolo.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=10783