PR libstdc++/19510

	PR libstdc++/19510
	* include/bits/stl_list.h (_List_iterator): Initialize _M_node
	in constructor.
	(_List_const_iterator): Likewise.
	* include/bits/stl_tree.h (_Rb_tree_iterator): Likewise.
	(_Rb_tree_const_iterator): Likewise.

	* testsuite/23_containers/map/operators/1_neg.cc: Adjust line numbers.
	* testsuite/23_containers/set/operators/1_neg.cc: Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@94002 138bc75d-0d04-0410-961f-82ee72b054a4