PR c++/34758
	* call.c (convert_default_arg): Use DECL_ORIGIN of fn.  Check for
	recursion first.
	(push_defarg_context, pop_defarg_context): New.
	* parser.c (cp_parser_late_parsing_default_args): Use them.
	* cp-tree.h: Declare them.

From-SVN: r171009