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Subject: Re: [PATCH] libbpf: Initialize *nl_pid so gcc 10 is happy
To:     Jeremy Cline <jcline@redhat.com>,
        Alexei Starovoitov <ast@kernel.org>
Cc:     Martin KaFai Lau <kafai@fb.com>, Song Liu <songliubraving@fb.com>,
        Yonghong Song <yhs@fb.com>, Andrii Nakryiko <andriin@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@chromium.org>,
        "David S . Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Jesper Dangaard Brouer <hawk@kernel.org>,
        netdev@vger.kernel.org, bpf@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20200404051430.698058-1-jcline@redhat.com>
From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <977ea25b-01bc-c1aa-eb93-e51ff916da0f@iogearbox.net>
Date:   Mon, 6 Apr 2020 22:14:45 +0200
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On 4/4/20 7:14 AM, Jeremy Cline wrote:
> Builds of Fedora's kernel-tools package started to fail with "may be
> used uninitialized" warnings for nl_pid in bpf_set_link_xdp_fd() and
> bpf_get_link_xdp_info() on the s390 architecture.
> 
> Although libbpf_netlink_open() always returns a negative number when it
> does not set *nl_pid, the compiler does not determine this and thus
> believes the variable might be used uninitialized. Assuage gcc's fears
> by explicitly initializing nl_pid.
> 
> Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1807781
> Signed-off-by: Jeremy Cline <jcline@redhat.com>

Applied, thanks!