Re: [PATCH] S390: Remove backchain-based fallback and use generic backtrace.c.

[Stefan Liebler <stli at linux dot ibm dot com>]

On 3/4/20 4:24 PM, Florian Weimer wrote:
> * Stefan Liebler:
>
> > After recent discussions:
> > - "[PATCH] s390: Remove backchain-based fallback from backtrace"
> >    https://www.sourceware.org/ml/libc-alpha/2020-02/msg00287.html
> >
> > - "Re: [PATCH 07/11] s390: Implement backtrace on top of <unwind-link.h>"
> >    https://www.sourceware.org/ml/libc-alpha/2020-02/msg00637.html
> >
> > We've checked and decided to remove the backchain:
> > We don't know of any environments without libgcc. Thus the backchain
> > unwinder is not used. If somebody builds with -mbackchain and without
> > fasynchronous-unwind-tables and has libgcc installed, then the
> > libgcc unwinder is called but not the backchain-based fallback.
> >
> > This step allows to get rid of the s390x specific backtrace.c files at all.
> > Furthermore the now used debug/backtrace.c version has some more
> > advantages:
> > - Free all resources if necessary. (libc_freeres_fn)
> > - Remove NULL address above _start.
> > - Check whether we make any progress while getting addresses.
>
> Looks good to me.  Thanks for doing this.
>
> Florian

Committed.

Thanks,
Stefan