[Dwarf-Discuss] DW_FORM_data1 and DW_AT_const_value

Michael Eager eager at eagercon.com
Mon Jul 26 15:53:23 PDT 2010


Roland McGrath wrote:
>> There is a distinction between "ambiguous" and "unspecified".
>> The interpretation of the value of DW_FORM_data is unspecified.
>> I don't believe that there is any ambiguity.
> 
> What I said was ambiguous was what the implications of that italicized
> (non-normative) paragraph were.  I take it you are saying that it's
> unambiguous in that paragraph that DW_FORM_data* interpretation is
> unspecified, and therefore unambiguous that the paragraph implies nothing
> about that interpretation.  Is that what you meant?

I don't think that either the normative or non-normative text
is ambiguous.  It is explicit that the interpretation of the
value is unspecified and must be determined by producer and
consumer agreeing to an interpretation.

> 
>>> I think it's wise (and is manifest existing practice) to use
>>> DW_FORM_data[124] freely and be clear that they imply zero-extension.
>> That is not the interpretation described in the DWARF standard.
> 
> You just said that the standard does not specify an interpretation.

You can't create an implication that DW_FORM_data is always
zero-extended based on the statement in the standard that the
interpretation is not specified.


-- 
Michael Eager	 eager at eagercon.com
1960 Park Blvd., Palo Alto, CA 94306  650-325-8077



More information about the Dwarf-Discuss mailing list