print_ubacktrace() and ppc 32

Holger Brunck holger.brunck@keymile.com
Tue Jun 18 07:01:00 GMT 2013


Hi,

On 06/17/2013 08:05 PM, Mark Wielaard wrote:
>> Unfortunately I believe this is because we don't actually support
>> > powerpc32 (only ppc64.h is defined in unwind.h).  So while the first
>> > error you're getting is being worked on (I'm currently working on
>> > PR10272[1] so hopefully it'll be resloved soon), the second error will
>> > be the show stopper here.
> Yeah thanks. I had completely forgotten I only implemented the DWARF
> unwinder for ppc64. Sorry. This was because when I wrote the powerpc
> DWARF unwinder (kernel support) I only had access to ppc64 kernels.
> 

ah ok thanks so it's currently unsupported.

> So for a ppc32 kernel we do need a new runtime/unwind/ppc32.h
> definitions file. It should not be that hard to write based on the
> ppc64.h version and the ppc32 DWARF register mappings from
> http://refspecs.linuxbase.org/elf/elfspec_ppc.pdf
> But note that testing might be needed to see if those really map to
> actually used DWARF register numbers generated by the toolchain. As can
> be seen in the comments in ppc64.h sometimes mistakes have been made and
> theory/spec and practice are not the same :{

Ok thanks for pointing out. If someone has a first ppc32.h file and needs
some help for testing on a native 32 bit ppc system, let me know. Or maybe
in the next week I find the time to implement one.

Best regards
Holger   



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