2012-04-23  Daniel Krugler  <daniel.kruegler@googlemail.com>

	* include/std/type_traits (is_nothrow_destructible): Implement.
	(is_destructible): Implement LWG 2049.
	* testsuite/util/testsuite_tr1.h: Add tests.
	* testsuite/20_util/is_nothrow_destructible/value.cc: New.
	* testsuite/20_util/is_nothrow_destructible/requirements/typedefs.cc:
	* testsuite/20_util/is_nothrow_destructible/requirements/
	explicit_instantiation.cc: Likewise.
	* testsuite/20_util/is_destructible/value.cc: Adjust and extend.
	* testsuite/20_util/is_default_constructible/value.cc: Tweak.
	* testsuite/20_util/is_constructible/value-2.cc: Likewise.
	* testsuite/20_util/make_signed/requirements/typedefs_neg.cc: Adjust
	dg-error line numbers.
	* testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc:
	Likewise.
	* testsuite/20_util/declval/requirements/1_neg.cc: Likewise.

From-SVN: r186726