Re: [PATCH][RESEND] fix compilation error with CROSS_COMPILE

[Sam Ravnborg <sam@ravnborg.org>]

On Sat, Aug 21, 2010 at 03:29:56PM +0800, Wu Fengguang wrote:
> On Sat, Aug 21, 2010 at 03:24:54PM +0800, Sam Ravnborg wrote:
> > On Sat, Aug 21, 2010 at 02:21:33PM +0800, Wu Fengguang wrote:
> > >         $ make CROSS_COMPILE=x86_64-linux-gnu-
> > >         ...
> > >         cc1: error: unrecognized command line option "-m64"
> > >         cc1: error: unrecognized command line option "-mno-red-zone"
> > >         cc1: error: unrecognized command line option "-mcmodel=kernel"
> > >         cc1: error: unrecognized command line option "-maccumulate-outgoing-args"
> > > 
> > > Cc: Tiago Maluta <tiago.maluta@gmail.com>
> > > Cc: Michal Marek <mmarek@suse.cz>
> > > Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
> > > ---
> > > 
> > > Andrew: the compile error only occurs in the -mm tree
> > > The bug is introduced by patch "Linux has an recent option to define
> > > CROSS_COMPILE in menuconfig.".
> > > 
> > > diff --git a/Makefile b/Makefile
> > > index d646d69..af8864e 100644
> > > --- a/Makefile
> > > +++ b/Makefile
> > > @@ -190,7 +190,7 @@ SUBARCH := $(shell uname -m | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
> > >  export KBUILD_BUILDHOST := $(SUBARCH)
> > >  ARCH		?= $(SUBARCH)
> > >  CROSS_COMPILE	?=
> > > -CROSS_COMPILE	:= $(shell grep CONFIG_CROSS_COMPILE .config | cut -d'"' -f2)
> > > +CROSS_COMPILE	?= $(shell grep CONFIG_CROSS_COMPILE .config | cut -d'"' -f2)
> > 
> > I cannot see how this would solve your problem.
> > Any variable assigned using := or ?= can be overrided by  variable
> > assigned on the command line like this:
> > 
> >    make VAR=values
> > 
> > Please note that there is a big difference between the above and this:
> > 
> >     VAR=value make
> 
> Ah yes I'm using that form indeed. Sorry for the confusion.
> 
> > In the latter case you pass in VAR using the enviroment and it
> > is just like any other environment variable as seen from make.
> > 
> > On top of that the upstream kernel does not have the first
> > assignmnet to CROSS_COMPILE - so you need to update
> > your sources (or Andrews --mm is not recent enough.
> > 
> > Please try again with upstream kernel and let us know what you
> > conclude.
> 
> Upstream kernel uses the ?= form and runs always OK.
> 
> The recent -mm kernels I tried all have the problem.

Good.
Then we can assume that next -mm has this fixed when he picks up
this change from upstream. Or maybe -mm has a patch in needs for revert.

Took a quick looks at -mm and only fould this:
kbuild-fix-config_cross_compile-issue-in-config.patch
And this is already upstream.


So I suggest you to fix it locally and check that
next -mm is correct.

	Sam