[v3 PATCH] PR libstdc++/70437

[Ville Voutilainen]

Tested on Linux-PPC64.

2016-04-04  Ville Voutilainen  <ville.voutilai...@gmail.com>

     PR libstdc++/70437
     * include/bits/stl_pair.h (_ConstructiblePair,
    _ImplicitlyConvertiblePair, _MoveConstructiblePair,
    _ImplicitlyMoveConvertiblePair): Add shortcut conditions
    for same-type cases.
    * testsuite/20_util/pair/70437.cc: New.