[C++ PATCH] Kill DECL_SAVED_FUNCTION_DATA

[C++ PATCH] Kill DECL_SAVED_FUNCTION_DATA

https://gcc.gnu.org/ml/gcc-patches/2019-05/msg00377.html
	Kill DECL_SAVED_FUNCTION_DATA .
	* cp-tree.h (language_function): Remove x_auto_return_pattern.
	(current_function_auto_return_pattern): Delete.
	(lang_decl_fn): Replace saved_language_function with
	saved_auto_return type.
	(DECL_SAVED_FUNCTION_DATA): Delete.
	(DECL_SAVED_AUTO_RETURN_TYPE): New.
	(FNDECL_USED_AUTO): Correct documentation.
	* decl.c (duplicate_decls): Adjust AUTO return handling.
	(start_preparsed_function): Replace
	current_function_auto_return_pattern with
	DECL_SAVED_AUTO_RETURN_TYPE.  Remove DECL_SAVED_FUNCTION_DATA
	zapping.
	(finish_function): Likewise.
	(save_function_data): Delete.
	(fndecl_declared_return_type): Reimplement.
	* mangle.c (write_unqualified_name): Use DECL_SAVED_AUTO_RETURN_TYPE.
	* method.c (make_thunk, make_alias_for): Likewise.
	* parser.c (cp_parser_jump_statement): Likewise.
	* pt.c (do_auto_deduction): Likewise.
	* typeck.c (check_return_expr): Likewise.

From-SVN: r271015