Re: [RFA] rs6000-tdep.c: arch switching buglet

[Kevin Buettner <kevinb at redhat dot com>]

On Feb 12, 10:47am, Elena Zannoni wrote:

> I found an odd bug on the ppc.
> 
> For this target, the list of arches in bfd includes
> several that are not rupported in gdb, for instance powerpc:630.
> 
> If the user says:
> 
> set architecture powerpc:630 
> 
> What should happen?
> 
> set_architecture() calls gdbarch_update_p, which should fail (right?),
> and set_architecture should print an error message.
> 
> Instead, consider the rs6000 code in rs6000_gdbarch_init():
> 
>   /* Choose variant. */
>   v = find_variant_by_arch (arch, mach);
>   if (!v)
>     v = find_variant_by_name (power ? "power" : "powerpc");
> 
> This code will pick a different architecture, in this case
> powerpc:common, but gdb/multiarch doesn't know, and prints that the
> architecture has been successfully set to powerpc:630.
> 
> This code was put in place before the multiarch framework, and it has
> become obsolete. So, how about the following:
> 
> 
> 2002-02-12  Elena Zannoni  <ezannoni@redhat.com>
> 
> 	* rs6000-tdep.c (rs6000_gdbarch_init): Don't call
> 	find_variant_by_name, because it confuses the multiarch
> 	framework. Return NULL if there isn't an architecture with the
> 	user supplied name, instead of forcing a different one without
> 	recording the change with the multiarch machinery.
> 	(find_variant_by_name): Delete.

It took me a while to convince myself that find_variant_by_name()
wouldn't be useful in the future.  But, you're right, this code should
go.  Please commit it.

Thanks,

Kevin