[PATCH] powerpc: Remove backtrace implementation

[Adhemerval Zanella]

On 15/04/2021 11:42, Tulio Magno Quites Machado Filho wrote:
> Paul E Murphy via Libc-alpha <libc-alpha@sourceware.org> writes:
> 
>> Ping?  This seems like a beneficial change.  Using the unwind
>> information makes for a much more robust backtrace with other languages
>> which support C bindings but do not use the same ABI (specifically
>> calling to and from go code in C).
>>
>> Should we instead turn the existing ppc backtrace into a compat symbol?
>> This seems like it would address Tulio's issue with older binaries.
> 
> If we do this, we'll never be able to remove the old implementation, which was
> Adhemerval's goal.
> I particularly agree that duplicated code should be removed and I believe it
> would be helpful if libgcc had the fallback code.
> 

As before, I don't think this is a ABI breaker and making powerpc align
with other architecture simplifies the code and align the expectation.

And afaik all projects that do require fast unwinder do it themselves
(libsanitizer for instance) instead.