[Bug libstdc++/60734] Undefined behavior in g++-v4/bits/stl_tree.h

[bshastry at sec dot t-labs.tu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60734

Bhargava Shastry <bshastry at sec dot t-labs.tu-berlin.de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bshastry at sec dot t-labs.tu-berl
                   |                            |in.de

--- Comment #9 from Bhargava Shastry <bshastry at sec dot t-labs.tu-berlin.de> ---
Hi. I just noticed that there are two more instances of the undefined downcast
via static_cast that are not fixed by the said patch.

### Lines borrowed from bits/stl_tree.h [gcc 5.1.0]

883.      iterator
884.      end() _GLIBCXX_NOEXCEPT
885.      { return iterator(static_cast<_Link_type>(&this->_M_impl._M_header));
}
886.
887.      const_iterator
888.      end() const _GLIBCXX_NOEXCEPT
889.      {
890.        return const_iterator(static_cast<_Const_Link_type>
891.                              (&this->_M_impl._M_header));
892.      }

The undefined casts happen on line 885 and 890--891.