On Thu, Feb 25, 2021 at 11:42:45AM -0500, Frank Ch. Eigler via Dwz wrote: > > FWIW I looked a little at unifying these. For example, > > bfdopncls.c:bfd_get_alt_debug_link_info could look at both the build-id > > and .debug_sup. > > > > But, this seemed a bit weird. What if both appear and they are > > different? Then a single API isn't so great -- you want to check the ID > > corresponding to whatever was in the original file. > > If both appear and are different, can we characterize the elf file as > malformed?
Unsure, the DWARF spec only talks about .debug_sup, the NOTE is a GNU extension. > Does our current tooling produce such files? If it's an dwz without --dwarf-5 produces .gnu_debugaltlink in the referrers and .note.gnu.build-id in the supplemental object file. For dwz --dwarf-5, if it produced a .note.gnu.build-id, it would produce the same one, but I thought that if I produced that, then consumers could keep using that instead of .debug_sup which is the only thing defined in the standard, so in the end dwz --dwarf-5 only produces .debug_sup on both the referrers side and on the side of supplemental object file as DWARF specifies. Jakub