Re: [PATCH] Fix section type conflict in arch/ia64/xen/xen_pv_ops.c

[Takashi Iwai]

At Thu, 6 Nov 2008 22:48:48 +0100,
Sam Ravnborg wrote:
> 
> On Thu, Nov 06, 2008 at 10:57:21AM -0800, Jeremy Fitzhardinge wrote:
> > Takashi Iwai wrote:
> > >__initdata and const cannot be always a happy pair, as gcc-4.3.3 gives
> > >the compile errors like:
> > >
> > >  arch/ia64/xen/xen_pv_ops.c:156: error: xen_init_ops causes a section 
> > >  type conflict
> > >  arch/ia64/xen/xen_pv_ops.c:340: error: xen_iosapic_ops causes a section 
> > >  type conflict
> > >
> > >This patch simply removes const from data with __initdata.
> > >  
> > 
> > Yeah, I've seen these sort of messages before, but I don't see why 
> > there's an inherent problem with having const __initdata.
> > 
> > Sam?
> 
> The root problem here is that in some cases gcc will stuff this into
> a section marked CONST and in other cases not.
> So when we manually specify the section we better not mix const and
> non-const stuff in the same section.
> The problem is that it is very gcc dependent. I have with powerpc
> seen that the same code was not put in CONST with a 32 bit build,
> but with the 64 bit build it was.
> The only cure was to remove the const and use initdata.
> You can try to play with initconst - and it may work.
> But you need to have pretty good build coverage to be sure.

OK, then my original patch should do right :)
Do you guys see any problems with it?

Right now 2.6.28-rc kernel doesn't build, thus this is basically a
regression.


thanks,

Takashi
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/