On Wed, 2011-07-20 at 20:00 +0200, Jakub Jelinek wrote: > On Wed, Jul 20, 2011 at 10:16:10AM -0700, Michael Eager wrote: > > but wait until the DWARF committee has had an > > opportunity to review the proposal and incorporate it into a future version > > of DWARF. Should you discover a need for an additional opcode, simply add > > it to the implementation. > > I'm afraid we don't want to wait a few years for DWARF5 though, we need > this right now, which is why if DWARF committee preference is a new section, > I think we should introduce .debug_gnu_macro section and keep it as whole > as a GNU extension and propose .debug_macro section with the same content > for DWARF5. Then, if DWARF5 uses the same format, perfect, if it uses a > different one, the consumers could just choose to support both formats or > something and GCC as a producer would phase the GNU extension format out.
Since there is a version field, maybe we could make use of that. So the preliminary GNU vendor implementation of the .debug_macro section would use version 1. When DWARF5 is officially published we can check whether it still matches the preliminary implementation. If it does, the standard just blesses version 1 as the official version, if not it starts at 2 (or maybe 5 to match up with the spec number) so consumers know whether they are dealing with the preliminary implementation or the "officially blessed" spec compliant version. Cheers, Mark
