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Date: Wed, 22 May 2024 21:50:35 +0200
From: "Steinar H. Gunderson" <sesse@google.com>
To: Namhyung Kim <namhyung@kernel.org>
Cc: acme@kernel.org, linux-perf-users@vger.kernel.org,
	linux-kernel@vger.kernel.org, irogers@google.com
Subject: Re: [PATCH v4 1/3] perf report: Support LLVM for addr2line()
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On Wed, May 22, 2024 at 10:27:06AM -0700, Namhyung Kim wrote:
> I think it should support other DWARF use cases like
> unwinding and type info?

I don't actually know. I had a look, but could really only find
documentation for _writing_ DWARF info. However, I've hardly used LLVM
before, so it's entirely possible that I missed something.

> I remember bfd objdump is sometimes faster than llvm-objdump
> especially when no line numbers are requested IIRC.

Hm, I've never seen that. But it's impossible to say for sure
that no such case exists, of course.

> Anyway, nice work.  Maybe we can implement other use cases
> using LLVM and reduce the dependencies.

It's possible to remove the libbfd dependency entirely if that's a goal,
at least, but I don't know what the current thinking is. I'll be happy
to take a stab at it (I guess it's possible to test the PE support with
WINE fairly easily?).

I found out that if compiling with an older compiler, LLVM changes to
llvm::Optional and doesn't have .value_or(), so I need to fix that
(the patch is trivial, but it means I need to post a v5, I guess).
Is there anything else I need to do after that to get this merged?

/* Steinar */