Re: stack unwinding on aix

Mark Kettenis
2005-06-21T22:19:52Z

Date: Mon, 20 Jun 2005 23:25:50 -0700 (PDT)
From: "Kamal R. Prasad" <kamalpr@yahoo.com>

Hello,

I am trying to locate a piece of code in gdb 6.3
which does srack unwinding in AIX (5.3). When
unwinding the stack in my C code, I noticed a lot of
dummy frames whose pc points to the data segment
and/or outside th text segment(s). Can someone tell me
how gdb identifies such dummy frames and wherein the
code base it is? rs6000-tdep.c contains some algo for
frameless function detection etc.., but that isn't all
to it.

I'm afraid the AIX/RS6000/POWER code is suffering from quite a bit of
bit-rot. It's a bit of a mess, so I can't blame you for failing to
understand the code. The sparc, vax or m88k code might be much easier
for you to understand.. Look frame functions name xxx_frame_cache,
xxx_prev_register for code that does the stack unwinding.

Anyway, the AIX/RS6000/POWER support in gdb really could use some
loving care. AFAIK almost none of the gdb developers actually have
access to an AIX system. So I'm not sure we'll be able to help you.

Mark