Proposal: Rename DW_FORM_ref_addr to DW_FORM_ref_info

Related proposals: 991108.4, 0000410.4

Discussion
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At least two proposals as well as review comments re the V2.1 Draft 1 have
made attempts to better describe what DW_FORM_ref_addr really means/does.

Some of the V2 problem exists, not doubt, because DW_FORM_ref_addr gets
confused with an "address" -- which is exceedingly natural because of the
name. If we just change the name from DW_FORM_ref_addr to DW_FORM_ref_info
(chosen because it is a section offset into the .debug_info section), such
confusion should be much less likely.

[DW_FORM_addr is an address, of course, but not DW_FORM_ref_addr.]
^^^^ ^^^^^^^^

This need not be considered an incompatible change. No bits need to change
in any DWARF file, and no code needs to change in any DWARF producer or
consumer. Producers and consumers can phase in the DW_FORM_ref_info name
as soon or as late as they want, and can even #define one in terms of the
other to allow them to co-exist.

[Maybe that last paragraph would make a good italized comment to include
following the definition of DW_FORM_ref_info.]

The impetus for this proposal was to clarify the meaning of DW_FORM_ref_addr. The proposed name, DW_FORM_ref_info, didn't appear to be any clearer than the current name, nor was any other acceptable name proposed. Rejected.