* include/bits/stl_threads.h (_Atomic_swap): Kill it...

	(_Swap_lock_struct<>): ...and the horse it rode in on.
	* src/globals.cc (_Swap_lock_struct<>): Likewise.
	* include/ext/stl_rope.h (_Rope_RopeRep<>::_M_c_string_lock): New
	member to support...
	* include/ext/ropeimpl.h (rope<>::c_str): Follow *all* memory
	visibility rules related to POSIX threads.
	* testsuite/thread/pthread7-rope.cc: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@66507 138bc75d-0d04-0410-961f-82ee72b054a4