From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sam Ravnborg <sam@ravnborg.org>
Subject: Re: Merge headerfiles for m68k and m68knommu to arch/m68k/include/asm
Date: Sat, 13 Dec 2008 21:43:37 +0100
Message-ID: <20081213204337.GA27748@uranus.ravnborg.org>
References: <20081208205814.GA22697@uranus.ravnborg.org> <Pine.LNX.4.64.0812082359190.29640@anakin> <200812090026.06689.arnd@arndb.de>
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To: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>, Roman Zippel <zippel@linux-m68k.org>, linux-m68k <linux-m68k@vger.kernel.org>, Greg Ungerer <gerg@uclinux.org>, uclinux-dev <uclinux-dev@uclinux.org>, linux-kbuild <linux-kbuild@vger.kernel.org>
List-Id: linux-m68k@vger.kernel.org

On Tue, Dec 09, 2008 at 12:26:05AM +0100, Arnd Bergmann wrote:
> On Tuesday 09 December 2008, Geert Uytterhoeven wrote:
> > > I have used the following include guard:
> > > 
> > > #ifdef __uClinux__
> > > #include "atomic_no.h"
> > > #else
> > > #include "atomic_mm.h"
> > > #endif
> > > 
> > > gcc -E -dM for the two compilers revealed that this was the
> > > only symbol that differed.
> > 
> > I think you can share a toolchain for m68k and m68knommu, at least for the
> > kernel (I used my plain m68k toolchain when experimenting with m68knommu for
> > Amiga).
> > 
> > > With the above construct we do the "right thing" also for
> > > headers exported to userspace.
> > > But actually none of the headers using the above are
> > > subject for export at the moment so we could use a
> > > CONFIG_ symbol for the same.
> > 
> > So I prefer to just check CONFIG_MMU.
> 
> Some of them are, by means of include/asm-generic/Kbuild.asm, e.g.
> unistd.h!
> 
> I'm not sure if it's entirely correct, but I think you can use
> 
> #ifdef __KERNEL__
> # ifdef CONFIG_MMU
> #  include "atomic_mm.h
> # else
> #  include "atomic_no.h
> # endif
> #else
> # ifndef __uClinux__
> #  include "atomic_mm.h
> # else
> #  include "atomic_no.h
> # endif
> #endif

I kept the original way of doing it since all reports said that
__uClinux__ is set by the m68knommu toolchain.
Using only this symbol makes it simpler what happens.

	Sam