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Subject: Re: [PATCH bpf] selftests/bpf: make directory prerequisites
 order-only
To:     Ilya Leoshkevich <iii@linux.ibm.com>, bpf@vger.kernel.org,
        netdev@vger.kernel.org
Cc:     gor@linux.ibm.com, heiko.carstens@de.ibm.com
References: <20190712135631.91398-1-iii@linux.ibm.com>
From:   Daniel Borkmann <daniel@iogearbox.net>
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Date:   Tue, 16 Jul 2019 00:19:26 +0200
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On 7/12/19 3:56 PM, Ilya Leoshkevich wrote:
> When directories are used as prerequisites in Makefiles, they can cause
> a lot of unnecessary rebuilds, because a directory is considered changed
> whenever a file in this directory is added, removed or modified.
> 
> If the only thing a target is interested in is the existence of the
> directory it depends on, which is the case for selftests/bpf, this
> directory should be specified as an order-only prerequisite: it would
> still be created in case it does not exist, but it would not trigger a
> rebuild of a target in case it's considered changed.
> 
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>

Applied, thanks!