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Date: Mon, 22 Aug 2011 16:42:48 +0800
From: Cong Wang <amwang@redhat.com>
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To: Arnaud Lacombe <lacombar@gmail.com>
CC: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [RFC] Kbuild: allow code re-use across different directories
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于 2011年08月20日 08:37, Arnaud Lacombe 写道:
> Hi folks,
>
> The attached patch modify Kbuild to allow to directly re-use code in multiple
> directory without having to go through a copy. Technically, it changes Kbuild to
> use by default the VPATH feature of GNU make and provides accessors for Makefile
> to change it indirectly.
...
>
> With the attached patch, we would do:
>
> arch/foo/boot/Makefile:
> LDFLAGS_fancy.o := -DPANTS=30
> obj-y += fancy.o
> vpath-y += $(srctree)/arch/foo/lib
>
> and let GNU make do the job.

Just note that don't forget to update Documentation/kbuild/makefiles.txt. ;)

Thanks.