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Date:   Mon, 23 May 2022 08:45:24 -0700
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Subject: Re: [PATCH v2] libbpf: Fix determine_ptr_size() guessing
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To:     Douglas RAILLARD <douglas.raillard@arm.com>, bpf@vger.kernel.org
Cc:     beata.michalska@arm.com, Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, llvm@lists.linux.dev
References: <20220523102955.43844-1-douglas.raillard@arm.com>
From:   Yonghong Song <yhs@fb.com>
In-Reply-To: <20220523102955.43844-1-douglas.raillard@arm.com>
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On 5/23/22 3:29 AM, Douglas RAILLARD wrote:
> From: Douglas Raillard <douglas.raillard@arm.com>
> 
> One strategy employed by libbpf to guess the pointer size is by finding
> the size of "unsigned long" type. This is achieved by looking for a type
> of with the expected name and checking its size.
> 
> Unfortunately, the C syntax is friendlier to humans than to computers
> as there is some variety in how such a type can be named. Specifically,
> gcc and clang do not use the same name in debug info.
> 
> Lookup all the names for such a type so that libbpf can hope to find the
> information it wants.
> 
> Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>

Acked-by: Yonghong Song <yhs@fb.com>