2011-09-11  Daniel Krugler  <daniel.kruegler@googlemail.com>

	PR libstdc++/50159
	* include/std/tuple (tuple_cat): Reimplement according to the
	resolution of LWG 1385.
	* include/std/type_traits: Define __and_ and __or_ for zero
	arguments too; minor tweaks.
	* testsuite/20_util/tuple/creation_functions/tuple_cat.cc: New.
	* testsuite/20_util/tuple/creation_functions/constexpr.cc: Disable
	for now tuple_cat test.
	* testsuite/20_util/declval/requirements/1_neg.cc: Adjust dg-error
	line numbers.
	* testsuite/20_util/make_signed/requirements/typedefs_neg.cc: Likewise.
	* testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc:
	Likewise.
	* doc/xml/manual/status_cxx200x.xml: Update.