[Bug libstdc++/53339] unordered_map::iterator requires Value to be complete type

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53339

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
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                 CC|                            |bkoz at redhat dot com

--- Comment #2 from Paolo Carlini <paolo.carlini at oracle dot com> 2012-05-14 02:24:14 UTC ---
But things seem not so easy in mainline (this is an enhancement which can go
only in mainline): in any case we fail at the line:

  using mapped_type = typename _Pair::second_type;

in hashtable_policy.h, because, afaics, with the code reworked to use alias
templates we end up instantiating everything down to __detail::_Map_base.