[Reproducible-builds] Bug#808267: diffoscope: Redundant information in ELF comparisons

[Mike Hommey]

On Mon, Jan 18, 2016 at 07:20:38PM +0100, Jérémy Bobbio wrote:
> Hi Mike,
> 
> Mike Hommey:
> > When comparing ELF files, the following commands are used:
> > - readelf --all
> > - readelf --debug-dump
> > - objdump --disassemble --full-contents
> > 
> > objdump --disassemble --full-contents is actually redundant in itself. For
> > example, it will dump both an hexdump and a disassembly of the .text section.
> > It's also redundant with the output of readelf --debug-dump because it does an
> > hexdump of the .debug_* sections that readelf --debug-dump does a dwarf dump
> > of.
> 
> The master branch now compare ELF files section by section. If you could
> test it and see if there's still redundancies, I would be grateful.

It seems better, but there's still redundancy at least between `readelf
--wide --all` and `readelf --wide --hex-dump
{.symtab,.note.gnu-build-id,.rela.dyn,.rela.plt,.dynamic,.dynsym}` and other
sections ; just check the list of sections in the output of readelf
--all.

Reading the code suggests debug sections would also be redunded between
--debug-dump and --hex-dump for the individual sections, but I haven't
tested with binaries with debuginfo.

Mike