Re: 2.6.22-rc4-mm2: kvm compile breakage with X86_CMPXCHG64=n

[Adrian Bunk <bunk@stusta.de>]

On Tue, Jun 12, 2007 at 03:03:57PM -0700, Andrew Morton wrote:
> On Mon, 11 Jun 2007 23:22:24 -0400
> Dave Jones <davej@redhat.com> wrote:
> 
> > Add -Werror-implicit-function-declaration
> > This makes builds fail sooner if something is implicitly defined instead
> > of having to wait half an hour for it to fail at the linking stage.
> > 
> > Signed-off-by: Dave Jones <davej@redhat.com>
> > 
> > --- linux-2.6/Makefile~	2007-06-04 16:46:24.000000000 -0400
> > +++ linux-2.6/Makefile	2007-06-04 16:46:53.000000000 -0400
> > @@ -313,7 +313,8 @@ LINUXINCLUDE    := -Iinclude \
> >  CPPFLAGS        := -D__KERNEL__ $(LINUXINCLUDE)
> >  
> >  CFLAGS          := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
> > -                   -fno-strict-aliasing -fno-common
> > +		   -fno-strict-aliasing -fno-common \
> > +		   -Werror-implicit-function-declaration
> >  AFLAGS          := -D__ASSEMBLY__
> >  
> >  # Read KERNELRELEASE from include/config/kernel.release (if it exists)
> 
> This causes the i386 allmodconfig build to fail:
> 
> include/linux/uaccess.h: In function 'pagefault_disable':
> include/linux/uaccess.h:23: error: implicit declaration of function '__memory_barrier'
> 
> I didn't look to see why...

I have -Werror-implicit-function-declaration in the CFLAGS of my 
testbuilds for ages without ever hitting this.

Perhaps some change in your working tree?
Can you verify this problem with 2.6.22-rc4-mm2?

cu
Adrian

-- 

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       "Only a promise," Lao Er said.
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