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Date:   Mon, 22 Oct 2018 21:03:56 -0700
From:   Andi Kleen <ak@linux.intel.com>
To:     Milian Wolff <milian.wolff@kdab.com>
Cc:     linux-kernel@vger.kernel.org, Jiri Olsa <jolsa@kernel.org>,
        namhyung@kernel.org, linux-perf-users@vger.kernel.org,
        Arnaldo Carvalho <acme@kernel.org>
Subject: Re: Broken dwarf unwinding - wrong stack pointer register value?
Message-ID: <20181023040356.GA6218@tassilo.jf.intel.com>
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> So what if my libm wasn't compiled with -fasynchronous-unwind-tables? We 

It's default (64bit since always and 32bit now too) Unless someone disabled it.

However libm might be partially written in assembler and hand written assembler
often has problems with unwind tables because the programmer has to get them
correct explicitely.

-Andi