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Message-ID: <60ab339a-3029-42db-97cf-d8574d05e789@daynix.com>
Date:   Mon, 16 Oct 2023 20:57:17 +0900
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Subject: Re: [PATCH bpf-next] selftests/bpf: Use pkg-config to determine ld
 flags
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To:     Daniel Borkmann <daniel@iogearbox.net>
Cc:     Andrii Nakryiko <andrii@kernel.org>,
        Mykola Lysenko <mykolal@fb.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Song Liu <song@kernel.org>,
        Yonghong Song <yonghong.song@linux.dev>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>,
        Shuah Khan <shuah@kernel.org>, Nick Terrell <terrelln@fb.com>,
        bpf@vger.kernel.org, linux-kselftest@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20231015133916.257197-1-akihiko.odaki@daynix.com>
 <062d9a75-caa0-d05d-14db-cd59dafab8b9@iogearbox.net>
From:   Akihiko Odaki <akihiko.odaki@daynix.com>
In-Reply-To: <062d9a75-caa0-d05d-14db-cd59dafab8b9@iogearbox.net>
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On 2023/10/16 20:39, Daniel Borkmann wrote:
> On 10/15/23 3:39 PM, Akihiko Odaki wrote:
>> When linking statically, libraries may require other dependencies to be
>> included to ld flags. In particular, libelf may require libzstd. Use
>> pkg-config to determine such dependencies.
> 
> Is this not covered via -lz or is it that the name differs?

libelf may not only be linked with zlib but also with zstandard.

> 
> Anyway, this change breaks selftest build for BPF CI (see below), could 
> this
> either be made optional or detected differently?
> 
> https://github.com/kernel-patches/bpf/actions/runs/6524480596/job/17716170021

I sent v2 (I forgot to add bpf-next to the subject for this).
This version implements a fallback just in the same way done for 
HOSTPKG_CONFIG.