Getting rid of the symbol_ranges and aliases stuff

[Daniel Berlin <dan@dberlin.org>]

If I implement the LOC_COMPUTED and LOC_COMPUTED_ARG, does anyone object 
to me removing SYMBOL_RANGES and SYMBOL_ALIASES in the process?

Reasons:
1. The only thing that generates this is redhat internal, and I don't 
think that gcc even has it enabled by default.
2. It wastes 8 bytes in every symbol (because it's implemented at the 
wrong level).
3. It's STABS specific.
4. It's subsumed by LOC_COMPUTED.
5. It's probably not been tested in a *long* time, since only redhat 
internal gcc can generate the info, and it's not done by default.


This is the live range splitting extensions to stabs stuff.  It works by 
having multiple symbols that are aliases to a given symbol at a given PC. 
In effect, it uses multiple symbols to simulate DWARF2 location lists.
It could be reimplemented in terms of location functions, cleanly.

But since nothing publicly available generates the info, I can't do that 
as part of a LOC_COMPUTED and LOC_COMPUTED_ARG implementation.
Nor do I think I should be required to.


--Dan