Subject: Re: linux-next: build failure

From: Ingo Molnar <[email-masked]>
Date: Tue, 29 Jul 2008 13:40:29 +0200

* KOSAKI Motohiro <[email-masked]> wrote:

> > 
> > * Stephen Rothwell <[email-masked]> wrote:
> > 
> > > Hi Ingo,
> > > 
> > > On Tue, 29 Jul 2008 10:00:55 +0200 Ingo Molnar <[email-masked]> wrote:
> > > >
> > > > > -#define cpumask_of_cpu(cpu) ({ *get_cpu_mask(cpu); })
> > > > > +#define cpumask_of_cpu(cpu) (*get_cpu_mask(cpu))
> > > > 
> > > > hm, i'm wondering - is this a compiler bug?
> > > 
> > > Or maybe a deficiency in such an old compiler (v3.4.5) but the fix 
> > > makes sense anyway, right?
> > 
> > yeah, i was just wondering.
> 
> in linux/README
> 
> COMPILING the kernel:
> 
>  - Make sure you have at least gcc 3.2 available.
>    For more information, refer to Documentation/Changes.
> 
> So, if 3.4.5 is old, Should we change readme?

the fix is simple enough.

but the question is, wont it generate huge artificial stackframes with 
CONFIG_MAXSMP and NR_CPUS=4096? Maybe it is unable to figure out and 
simplify the arithmetics there - or something like that.

	Ingo