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Subject: Re: [RFC PATCH v4 3/3] bpf: Introduce function for outputing data to
 perf event
To: He Kuang <hekuang@huawei.com>, pi3orama <pi3orama@163.com>,
        Namhyung Kim <namhyung@kernel.org>
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On 7/14/15 4:54 AM, He Kuang wrote:
>> I'm not sure llvm generates proper dwarf along with bpf code (I didn't
>> test that part. If there are any issues they should be fixable. If you
>> can prepapre a patch for llvm that would be even better :)
>>
>
> I found objdump can't get dwarf info from bpf object file:
>
>    $ objdump --dwarf=info bpf.o
>    bpf.o: file format elf64-little
>
>    $ readelf -a bpf.o |grep debug_info
>    <EMPTY>

yeah. looks like this part is not working.
Interesting that when I do: clang -O2 -target bpf a.c -g -S
there is some minimal debug info in the .s, but .o lacks
debuginfo completely. Digging further...
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