2010-12-04  Jonathan Wakely  <jwakely.gcc@gmail.com>

	* include/std/mutex (try_lock, __try_lock_impl): Fix.
	(lock): Implement using __try_lock_impl.
	* testsuite/30_threads/try_lock/2.cc: Fix logic.
	* testsuite/30_threads/try_lock/4.cc: New.
	* testsuite/30_threads/lock/1.cc: New.
	* testsuite/30_threads/lock/2.cc: New.
	* testsuite/30_threads/lock/3.cc: New.
	* testsuite/30_threads/lock/4.cc: New.

From-SVN: r167452