cp-tree.h (OVL_CHAIN): Check looking at OVERLOAD.

cp-tree.h (OVL_CHAIN): Check looking at OVERLOAD.

	* cp-tree.h (OVL_CHAIN): Check looking at OVERLOAD.
	(ovl_iterator): Add allow_inner field.  Adjust ctor.  Make
	unduplicatable.
	(ovl_iterator::maybe_push, ovl_iterator::pop): New.
	(lkp_iterator): Add outer field.  Adjust ctor.
	(lkp_iterator::operator++): New.
	(lookup_mark, lookup_maybe_add): Declare.
	* name-lookup.c (name_lookup): Delete fn_set member.
	(name_lookup::preserve_state, name_lookup::restore_state): Unmark
	and mark lookup.
	(name_lookup::add_value): Use lookup_add directly.
	(name_lookup::add_fns: Use lookup_maybe_add.
	(name_lookup::search_adl): Mark and unmark fns.
	(pushdecl): Adjust.
	* pt.c (check_explicit_specialization): Use lookup_add directly.
	* ptree.c (cxx_print_xnode): Show complete overload structure.
	* tree.c (lookup_mark, lookup_maybe_add): New.

From-SVN: r248517