Re: [PATCH] PR gdb/21226: Take DWARF stack value pieces from LSB end

[Andreas Arnez <arnez@linux.vnet.ibm.com>]

On Fri, Mar 10 2017, Ulrich Weigand wrote:

> Andreas Arnez wrote:
>> On Fri, Mar 10 2017, Ulrich Weigand wrote:
>> 
>> > Andreas Arnez wrote:
>> >
>> > Sorry, I overlooked one other issue:
>> >
>> >> +	    /* Piece offset is from least significant bit end.  */
>> >> +	    if (bits_big_endian)
>> >> +	      source_offset_bits += obj_size - (p->offset + p->size);
>> >> +	    else
>> >> +	      source_offset_bits += p->offset;
>> >
>> > Should this really consult bits_big_endian, as opposed to the
>> > regular byte order?  Note that in the DWARF_VALUE_REGISTER case,
>> > we have the same issue, and there the byte order is consulted.
>> 
>> Using the byte order would strictly be more correct, yes.  As opposed to
>> register pieces, we would have to get it from a different gdbarch,
>> though.  I think the right one would be the objfile gdbarch of the
>> underlying CU, right?
>
> That sounds right, and is compatible with what is done for full
> DWARF_VALUE_STACK values in dwarf2_evaluate_loc_desc_full.

Right -- which reminds me...  A month ago I provided a patch for that as
well:

  https://sourceware.org/ml/gdb-patches/2017-03/msg00041.html

--
Andreas