(Putting this discussion back on the original thread…) >>> ---[ sketch of DWARF for file 2 ]--- >>> >>> DW_TAG_subprogram 'read_nml' >>> DW_TAG_imported_declaration '/nml' >>> DW_AT_import DW_FORM_ref_addr [ somehow a reference to $1 ] >> >> Well, that's probably the problem: The "somehow". If the files are generated >> independently, the "reference to $1" is not available. At least that's how I >> understand it. (My DWARF knowledge is rather weak.) > > At least on ELF and PECOFF platforms it's perfectly possible: you just insert > a reference to a global symbol declared in the DWARF section of another > object file. Our compiler doesn't use this particular tag, but at least for > e.g. DW_TAG_typedef it works fine with gdb.
Yes, but the compiler has to anticipate the need for the reference by generating a global symbol when compiling the other file. This is why DW_FORM_ref_addr isn't used much outside of contexts where the entire program is visible (e.g., dwz). Another problem with using DW_FORM_ref_addr is that it's not compatible with split dwarf (aka "Fission"), because the .dwo files are stripped of both ELF symbols and relocations. I think it'd probably be simpler to just emit an empty DW_TAG_namelist, maybe with the DW_AT_declaration flag set. Let the debugger find the definition of the namelist via the DW_AT_name. -cary _______________________________________________ Dwarf-Discuss mailing list Dwarf-Discuss@lists.dwarfstd.org http://lists.dwarfstd.org/listinfo.cgi/dwarf-discuss-dwarfstd.org
