🚀 go-pugleaf

On 2018-03-02, Bob Eager <news...@eager.cx> wrote:

> On Fri, 02 Mar 2018 01:11:55 +0000, Charlie Gibbs wrote:
>
>> On 2018-03-01, Bob Eager <news...@eager.cx> wrote:
>> 
>>> On Thu, 01 Mar 2018 16:41:20 -0600, Charles Richmond wrote:
>>>
>>>> Cross references were good to use with a hex dump of your program.  In
>>>> the early 1980's I used a cross reference and a hex dump to find the
>>>> value of FORTRAN variables at the time the program crashed.
>>>> numerist at aquaporin4 dot com
>>>> 
>>>> Using DDT under TOPS-10 or dbx under Unix, or gdb under Linux... one
>>>> can find the value of variables when the program "dumped core".  This
>>>> obviated the need for a cross reference.
>>>
>>> I think that's conflating two separate things:
>>> a) cross reference b) symbol table
>> 
>> A cross-reference listing is a symbol table dump with reference data
>> added.
>
> I have rarely seen the two combined. A symbol table is names and 
> (possibly relocatable) offsets in a PSECT ot whatever. A cross reference 
> is names and line numbers. The two have different purposes, and I have 
> seen many assemblers where you can request one or both of those - 
> separately.

Perhaps I overgeneralized.  Indeed, a freestanding cross-reference
utility would have to do a lot of work to provide more than the
line number in which a symbol was defined and the line numbers in
which it was referenced.  The assembler or compiler, on the other
hand, knows the symbol's value, length attribute, type attribute,
relocation attribute, etc.  If it writes these out to a work file,
along with line numbers where the symbol is used, it's possible
to generate a pretty comprehensive report from the result.

-- 
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