Re: [Libunwind-devel] [PATCH] arm: ptrace: Fix order of probing unwind tables

[Vitaly_Kuzmichev]

From: Vitaly Kuzmichev <address@hidden>

Hi Yichao Yu,

In your patch libunwind-prefer-extbl.patch you say that ARM EXTBL unwinding
"seems to be more reliable". This contradicts Ken Werner's commit 92327a3
description where DWARF is called "more powerful than the ARM specific
unwind tables".

Do you have any code example demonstrating advantage of using ARM EXTBL
in prior to DWARF? Or your words were rather a guess?

Unfortunately, I can not say that EXTBL is reliable, it does not provide
function end offset (nor its size), so IP-to-function mapping can not
be precise, so not really reliable.

I can try to check your patchset with our code example of unwinding remote
process doing division by zero. I will let you know of results.

Regards,
Vitaly.