kbuild: O= with M= (Re: [PATCH -mm] replacement for broken kbuild-dont-put-temp-files-in-the-source-tree.patch)

[Oleg Verych <olecom@flower.upol.cz>]

On Tue, Oct 31, 2006 at 02:51:36PM +0100, olecom wrote:
[]
> On Tue, Oct 31, 2006 at 02:14:16AM +0100, Horst Schirmeier wrote:
[]
> > I'm not sure what you mean by $(objdir); I just got something to work
> > which creates the /dev/null symlink in a (newly created if necessary)
> > directory named
> 
> $(objtree) is a directory for all possible outputs of the build precess,
> it's set up by `O=' or `KBUILD_OUTPUT', and this is *not* output for ready
> external modules `$(M)'. Try to play with this, please.

And for me, they are *not* working together:

,--[shell]--
|olecom@deen:/tmp/linux-source-2.6.18$ make clean
|olecom@deen:/tmp/linux-source-2.6.18$ make M=$a
|  LD      /mnt/work/app-src-build/kernel.org/_work/ti_usb/built-in.o
|  CC [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.o
|  Building modules, stage 2.
|  MODPOST
|  CC      /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.mod.o
|  LD [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.ko
|olecom@deen:/tmp/linux-source-2.6.18$
|olecom@deen:/tmp/linux-source-2.6.18$ make clean
|olecom@deen:/tmp/linux-source-2.6.18$ make O=/tmp/_build-2.6/ M=$a
|  CC [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.o
|  Building modules, stage 2.
|  MODPOST
|/bin/sh: scripts/mod/modpost: not found
|make[2]: *** [__modpost] Error 127
|make[1]: *** [modules] Error 2
|make: *** [_all] Error 2
|olecom@deen:/tmp/linux-source-2.6.18$ make clean
|olecom@deen:/tmp/linux-source-2.6.18$ make M=$a
|  CC [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.o
|  Building modules, stage 2.
|  MODPOST
|  LD [M]  /mnt/work/app-src-build/kernel.org/_work/ti_usb/ti_usb_3410_5052.ko
|olecom@deen:/tmp/linux-source-2.6.18$
`--

I'm using 'O=' as good way to have clean kernel source directory,
regardless of any "ignore files" policy. And it seems, must be fixed.

> I'm looking for Sam to say something, if we must go further with this.
> ____
____