PR libstdc++/55917
	* src/c++11/thread.cc (execute_native_thread_routine): Remove
	try-block so that exceptions propagate out of the thread and terminate
	is called by the exception-handling runtime.
	(execute_native_thread_routine_compat): Likewise.
	* testsuite/30_threads/thread/cons/terminate.cc: New.

From-SVN: r249130