2011-11-21  Daniel Krugler  <daniel.kruegler@googlemail.com>

	PR libstdc++/51185
	* include/std/type_traits (__is_base_to_derived_ref,
	__is_lvalue_to_rvalue_ref): Fix.
	* testsuite/20_util/is_constructible/51185.cc: New.
	* testsuite/20_util/is_constructible/value-2.cc: Extend.

From-SVN: r181557