Re: [PATCH] S390: Add use of unavailable-stack frame ID

[Pedro Alves <palves@redhat.com>]

On 03/07/2016 10:19 AM, Andreas Arnez wrote:
> When determining the frame ID of an inline frame, GDB currently asserts
> that a valid ID of the underlying real frame is found, and that it does
> not match outer_frame_id.  From inline_frame_this_id():
>
>    /* For now, require we don't match outer_frame_id either (see
>       comment above).  */
>    gdb_assert (!frame_id_eq (*this_id, outer_frame_id));
>
> However, this assertion may fail when the real frame's unwinder can not
> determine the frame ID.  This happened on an s390x target with a binary
> that lacked call frame information and also confused the prologue
> analyzer, because then s390_frame_this_id() left the frame ID at its
> default.
>
> To fix this, this change enhances s390_frame_this_id such that an
> unavailable-stack frame ID is built if no frame base can be determined
> but the function address is available.
>

Seeing all these makes me want this:

  https://sourceware.org/ml/gdb-patches/2016-02/msg00778.html

even more.  :-)

Thanks,
Pedro Alves