Re: [PATCH] x86: reject architecture settings that are invalid to be set from the command line

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Wed, Jun 9, 2010 at 8:36 AM, Jan Beulich <JBeulich@novell.com> wrote:
> So far, options like -march=i8086 were accepted despite the assembler
> subsequently choking on other consistency checks, leading to reasonably
> cryptic error messages. This patch makes it so that impossible
> architecure settings are neither accepted nor displayed (i.e. it is now
> made sure that those settings can only be used via directives).
>
> gas/
> 2010-06-09 ?Jan Beulich ?<jbeulich@novell.com>
>
> ? ? ? ?* config/tc-i386.c (md_parse_option): Ignore impossible processor
> ? ? ? ?types.
> ? ? ? ?(show_arch): New parameter 'check'.
> ? ? ? ?(md_show_usage): Adjust calls to show_arch().
>
> --- 2010-06-09/gas/config/tc-i386.c ? ? 2010-06-09 17:04:12.000000000 +0200
> +++ 2010-06-09/gas/config/tc-i386.c ? ? 2010-06-09 17:24:59.000000000 +0200
> @@ -8166,6 +8166,11 @@ md_parse_option (int c, char *arg)
> ? ? ? ? ? ? ?if (strcmp (arch, cpu_arch [j].name) == 0)
> ? ? ? ? ? ? ? ?{
> ? ? ? ? ? ? ? ? ?/* Processor. ?*/
> + ? ? ? ? ? ? ? ? if (! (strcmp (default_arch, "i386")
> + ? ? ? ? ? ? ? ? ? ? ? ?? cpu_arch[j].flags.bitfield.cpulm
> + ? ? ? ? ? ? ? ? ? ? ? ?: cpu_arch[j].flags.bitfield.cpui386))
> + ? ? ? ? ? ? ? ? ? continue;
> +
> ? ? ? ? ? ? ? ? ?cpu_arch_name = cpu_arch[j].name;
> ? ? ? ? ? ? ? ? ?cpu_sub_arch_name = NULL;
> ? ? ? ? ? ? ? ? ?cpu_arch_flags = cpu_arch[j].flags;
> @@ -8297,7 +8302,7 @@ md_parse_option (int c, char *arg)
> ?" ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?"
>
> ?static void
> -show_arch (FILE *stream, int ext)
> +show_arch (FILE *stream, int ext, int check)
> ?{
> ? static char message[] = MESSAGE_TEMPLATE;
> ? char *start = message + 27;
> @@ -8334,6 +8339,13 @@ show_arch (FILE *stream, int ext)
> ? ? ? ? ?/* It is an processor. ?Skip if we show only extension. ?*/
> ? ? ? ? ?continue;
> ? ? ? ?}
> + ? ? ?else if (check && ! (strcmp (default_arch, "i386")
> + ? ? ? ? ? ? ? ? ? ? ? ? ?? cpu_arch[j].flags.bitfield.cpulm
> + ? ? ? ? ? ? ? ? ? ? ? ? ?: cpu_arch[j].flags.bitfield.cpui386))
> + ? ? ? {
> + ? ? ? ? /* It is an impossible processor - skip. ?*/
> + ? ? ? ? continue;
> + ? ? ? }
>
>

Do we need to check cpu_arch[j].flags.bitfield.cpulm? Can we
just check cpu_arch[j].flags.bitfield.cpui386 like

if (check && !cpu_arch[j].flags.bitfield.cpui386)
  continue?


-- 
H.J.