gcc:
	* builtin-attrs.def (gcc_diag, gcc_cdiag, gcc_cxxdiag): New
	format attributes.
	* c-format.c (enum format_type): Add gcc_diag_format_type,
	gcc_cdiag_format_type, and gcc_cxxdiag_format_type.
	(gcc_diag_length_specs, gcc_cdiag_length_specs,
	gcc_cxxdiag_length_specs, gcc_diag_flag_pairs,
	gcc_cdiag_flag_pairs, gcc_cxxdiag_flag_pairs, gcc_diag_flag_specs,
	gcc_cdiag_flag_specs, gcc_cxxdiag_flag_specs, gcc_diag_char_table,
	gcc_cdiag_char_table, gcc_cxxdiag_char_table): New.
	(format_types_orig): Add new data.
	(find_char_info_specifier_index, init_dynamic_diag_info): New
	functions.
	(handle_format_attribute): Update to handle new format attributes.

testsuite:
	* gcc.dg/format/gcc_diag-1.c: New test.

From-SVN: r68689