[ was: [RFC, gdb/exp] Handle DW_OP_GNU_variable_value refs to abstract
dies ]

On 08/24/2018 03:09 PM, Tom de Vries wrote:
> [ was: Re: [PATCH 1/3] Add support for DW_OP_GNU_variable_value ]
> 
> On 08/23/2018 11:12 PM, Kevin Buettner wrote:
>> On Wed, 22 Aug 2018 17:35:23 +0200
>> Tom de Vries <tdevries@suse.de> wrote:
>>
>>> On 08/18/2018 10:31 PM, Kevin Buettner wrote:
>>>>     This patch adds support for DW_OP_GNU_variable_value to GDB.
>>>>     
>>>>     Jakub Jelinek provides a fairly expansive discussion of this DWARF
>>>>     expression opcode in his GCC patch...
>>>>     
>>>>         https://gcc.gnu.org/ml/gcc-patches/2017-02/msg01499.html
>>>>     
>>>>     It has also been proposed for addition to the DWARF Standard:
>>>>     
>>>>         http://www.dwarfstd.org/ShowIssue.php?issue=161109.2  
>>> Hi,
>>>
>>> AFAIU from the discussion here (
>>> https://gcc.gnu.org/ml/gcc-patches/2018-08/msg01351.html ) if:
>>> - a DW_OP_GNU_variable_value refers to a die 'a', and
>>> - there's a die 'b' with abstract_origin 'a' that does have a
>>>   DW_AT_location, and
>>> - die 'b' is 'in scope' in an evaluation context,
>>> then the evaluation of DW_OP_GNU_variable_value 'a' should return the
>>> value found at the DW_AT_location of die 'b'.

Hi,

this patch implements the handling of DW_OP_GNU_variable_value refs to
abstract dies.

There's no test-case yet, I'll try to write one.

OK for trunk?

Thanks,
- Tom