(parse_args): Add --no-warn, --warn, --fatal-warnings,
which become 'W', OPTION_WARN, and OPTION_WARN_FATAL.
(parse_args): Parse the new options.
(main): If there were warnings, and --fatal-warnings
was specified, print an error.
* as.h: New variable, flag_fatal_warnings, for new option.
DWARF2 debug info (line information only, at this point).
* as.h: Update comment about supported debug formats.
* dwarf2dbg.c, dwarf2dbg.h: New files.
* Makefile.am (GAS_CFILES, HFILES, GENERIC_OBJS): Add them.
(app_push): Save saved_input in allocated buffer.
(app_pop): Restored saved_input.
(do_scrub_chars): Change get parameter to take char * and int as
arguments. Change GET macro to pass input_buffer to get
function. Don't save input into allocated buffer.
* as.h (do_scrub_chars): Update declaration.
* input-file.c (input_file_get): Change to take char * and int.
Read data into passed in buffer. Remove static buffer.
* read.c (scrub_from_string): Change to take char * and int. Copy
data into passed in buffer.
