Re: Using dwfl to enumerate frames of current thread

[Mark Wielaard <mjw@redhat.com>]

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On Thu, 2015-08-20 at 13:09 +0200, Ben Gamari wrote:
> It turns out that libbacktrace only uses DWARF line information, not
> the .debug_frames unwinding information.

It might indeed be that libbacktrace only handles .eh_frame.
If you already generate .debug_frame it should be easy to
generate .eh_frame information. The formats are almost the same with a
few small encoding differences (also .eh_frame can have a .eh_frame_hdr
index which makes address lookup and unwinding much more efficient).
http://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html
http://www.airs.com/blog/archives/460

Alternatively it might not be too hard to make libbacktrace
use .debug_frame if it is already loading the .debug_line info then
making it also load .debug_frame and interpret it mostly like .eh_frame
is. (elfutils libdw cie.c/fde.c use CFI_IS_EH to distinquish if you want
to see some of the practical differences)

Again, not wanting you to push away towards another library, but simply
pointing out different options.

Cheers,

Mark