PR fortran/31675

	* libgfortran.h: New file.
	* iso-fortran-env.def: Use macros in the new header instead of
	hardcoded integer constants.
	* Make-lang.in (F95_PARSER_OBJS, GFORTRAN_TRANS_DEPS): Add
	fortran/libgfortran.h.
	* gfortran.h (GFC_STD_*, GFC_FPE_*, options_convert,
	ioerror_codes): Remove.
	* trans.c (ERROR_ALLOCATION): Remove.
	(gfc_call_malloc, gfc_allocate_with_status,
	gfc_allocate_array_with_status): Use LIBERROR_ALLOCATION.
	* trans-types.h (GFC_DTYPE_*): Remove.
	* trans-decl.c (gfc_generate_function_code): Use
	GFC_CONVERT_NATIVE instead of CONVERT_NATIVE.
	* trans-io.c (set_parameter_value, set_parameter_ref): Use
	LIBERROR_* macros instead of IOERROR_ macros.
	* trans-intrinsic.c (gfc_conv_intrinsic_function): Use
	LIBERROR_END and LIBERROR_EOR instead of hardcoded constants.
	* options.c (gfc_init_options): Use GFC_CONVERT_NATIVE instead of
	CONVERT_NATIVE.
	(gfc_handle_option): Use GFC_CONVERT_* macros instead of CONVERT_*.

	* libgfortran.h: Include gcc/fortran/libgfortran.h.
	Remove M_PI, GFC_MAX_DIMENSIONS, GFC_DTYPE_*, GFC_NUM_RANK_BITS,
	error_codes, GFC_STD_*, GFC_FPE_* and unit_convert.
	* runtime/environ.c (variable_table): Use GFC_*_UNIT_NUMBER instead
	of hardcoded constants.
	(do_parse, init_unformatted): Use GFC_CONVERT_* macros instead of
	CONVERT_*.
	* runtime/string.c (find_option): Use LIBERROR_BAD_OPTION instead
	of ERROR_BAD_OPTION.
	* runtime/error.c (translate_error, generate_error): Use
	LIBERROR_* macros instead of ERROR_*.
	* io/file_pos.c (formatted_backspace, unformatted_backspace,
	st_backspace, st_rewind, st_flush): Rename macros.
	* io/open.c (convert_opt, edit_modes, new_unit, already_open,
	st_open): Likewise.
	* io/close.c (st_close): Likewise.
	* io/list_read.c (next_char, convert_integer, parse_repeat,
	read_logical, read_integer, read_character, parse_real,
	check_type, list_formatted_read_scalar, namelist_read,
	nml_err_ret): Likewise.
	* io/read.c (convert_real, read_l, read_decimal, read_radix,
	read_f): Likewise.
	* io/inquire.c (inquire_via_unit): Likewise.
	* io/unit.c (get_internal_unit): Likewise.
	* io/transfer.c (read_sf, read_block, read_block_direct,
	write_block, write_buf, unformatted_read, unformatted_write,
	formatted_transfer_scalar, us_read, us_write, data_transfer_init,
	skip_record, next_record_r, write_us_marker, next_record_w_unf,
	next_record_w, finalize_transfer, st_read, st_write_done):
	Likewise.
	* io/format.c (format_error): Likewise.

From-SVN: r128050